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Observation of e+e?→D+sDˉˉˉˉ(?)0K?e+e?→Ds+Dˉ(?)0K?and study of the P-wave DsDs mesons
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作者 麦迪娜 M.N.Achasov +143 位作者 S.Ahmed M.Albrecht M.Alekseev A.Amoroso 安芬芬 安琪 白羽 O.Bakina R.Baldini Ferroli 班勇 K.Begzsuren D.W.Bennett J.V.Bennett N.Berger M.Bertani D.Bettoni F.Bianchi I.Boyko R.A.Briere 蔡浩 蔡啸 A.Calcaterra 曹国富 S.A.Cetin J.Chai 常劲帆 W.L.Chang G.Chelkov 陈刚 陈和生 陈江川 陈玛丽 陈申见 陈元柏 成伟帅 G.Cibinetto F.Cossio 代洪亮 代建平 A.Dbeyssi D.Dedovich 邓子艳 A.Denig I.Denysenko M.Destefanis F.De Mori 丁勇 董超 董静 董燎原 董明义 豆正磊 杜书先 范荆州 方建 房双世 方易 R.Farinelli L.Fava F.Feldbauer G.Felici 封常青 M.Fritsch 傅成栋 付颖 高清 高鑫磊 高原宁 高勇贵 高榛 B.Garillon I.Garzia A.Gilman K.Goetzen 龚丽 龚文煊 W.Gradl M.Greco 谷立民 顾旻皓 顾珊 顾运厅 郭爱强 郭立波 郭如盼 郭玉萍 A.Guskov Z.Haddadi 韩爽 郝喜庆 F.A.Harris 何康林 F.H.Heinsius T.Held 衡月昆 侯治龙 胡海明 胡继峰 胡涛 胡誉 黄光顺 黄金书 黄性涛 黄晓忠 黄智玲 N.Huesken T.Hussain W.Ikegami Andersson W.Imoehl M.Irshad 纪全 姬清平 季晓斌 季筱璐 姜侯兵 江晓山 蒋兴雨 焦健斌 焦铮 金大鹏 金山 金毅 T.Johansson N.Kalantar-Nayestanaki 康晓珅 M.Kavatsyuk 柯百谦 I.K.Keshk T.Khan A.Khoukaz P.Kiese R.Kiuchi R.Kliemt L.Koch O.B.Kolcu B.Kopf M.Kuemmel M.Kuessner A.Kupsc M.Kurth W.Kühn J.S.Lange P.Larin L. 《中国物理C:英文版》 SCIE CAS CSCD 2019年第3期5-16,共12页
Studies of e+e?→D+sDˉˉˉˉ(?)0K?e+e?→Ds+Dˉ(?)0K?and the PP-wave charmed-strange mesons are performed based on an e+e?e+e?collision data sample corresponding to an integrated luminosity of 567 pb?1 collected with ... Studies of e+e?→D+sDˉˉˉˉ(?)0K?e+e?→Ds+Dˉ(?)0K?and the PP-wave charmed-strange mesons are performed based on an e+e?e+e?collision data sample corresponding to an integrated luminosity of 567 pb?1 collected with the BESIII detector at s√=4.600s=4.600 GeV.The processes of e+e?→D+sDˉˉˉˉ?0K?e+e?→Ds+Dˉ?0K?and D+sDˉˉˉˉ0K?Ds+Dˉ0K?are observed for the first time and are found to be dominated by the modes D+sDs1(2536)?Ds+Ds1(2536)?and D+sD?s2(2573)?Ds+Ds2?(2573)?,respectively.The Born cross sections are measured to beσB(e+e?→D+sDˉˉˉˉ?0K?)=(10.1±2.3±0.8)σB(e+e?→Ds+Dˉ?0K?)=(10.1±2.3±0.8)pb andσB(e+e?→D+sDˉˉˉˉ0K?)=(19.4±2.3±1.6)σB(e+e?→Ds+Dˉ0K?)=(19.4±2.3±1.6)pb,and the products of Born cross section and the decay branching fraction are measured to beσB(e+e?→D+sDs1(2536)?+c.c.)?σB(e+e?→Ds+Ds1(2536)?+c.c.)?B(Ds1(2536)?→Dˉˉˉˉ?0K?)=(7.5±1.8±0.7)B(Ds1(2536)?→Dˉ?0K?)=(7.5±1.8±0.7)pb andσB(e+e?→D+sD?s2(2573)?+c.c.)?B(D?s2(2573)?→Dˉˉˉˉ0K?)=σB(e+e?→Ds+Ds2?(2573)?+c.c.)?B(Ds2?(2573)?→Dˉ0K?)=(19.7±2.9±2.0)(19.7±2.9±2.0)pb.For the Ds1(2536)?Ds1(2536)?and D?s2(2573)?Ds2?(2573)?mesons,the masses and widths are measured to be M(Ds1(2536)?)=(2537.7±0.5±3.1)MeV/c2M(Ds1(2536)?)=(2537.7±0.5±3.1)MeV/c2,Γ(Ds1(2536)?)=(1.7±1.2±0.6)Γ(Ds1(2536)?)=(1.7±1.2±0.6)MeV,and M(D?s2(2573)?)=M(Ds2?(2573)?)=(2570.7±2.0±1.7)MeV/c2,(2570.7±2.0±1.7)MeV/c2,Γ(D?s2(2573)?)=(17.2±3.6±1.1)Γ(Ds2?(2573)?)=(17.2±3.6±1.1)MeV.The spin-parity of the D?s2(2573)?Ds2?(2573)?meson is determined to be JP=2+JP=2+.In addition,the processes e+e?→D+sDˉˉˉˉ(?)0K?e+e?→Ds+Dˉ(?)0K?are searched for using the data samples taken at four(two)center-of-mass energies between 4.416(4.527)and 4.575 GeV,and upper limits at the 90%confidence level on the cross sections are determined. 展开更多
关键词 cross section P-WAVE D_s MESONS resonance parameters spin-parity BESIII
Novel ATL1 mutation in a Chinese family with hereditary spastic paraplegia: A case report and review of literature 预览
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作者 Xue-Wen Xiao Juan Du +8 位作者 Bin Jiao Xin-Xin Liao Lu Zhou Xi-Xi Liu Zhen-Hua Yuan Li-Na Guo Xin Wang Lu Shen Zhang-Yuan Lin 《世界临床病例杂志》 2019年第11期1358-1366,共9页
BACKGROUND Hereditary spastic paraplegias (HSPs) refer to a group of heterogeneous neurodegenerative diseases characterized by lower limbs spasticity and weakness. So far, over 72 genes have been found to cause HSP (S... BACKGROUND Hereditary spastic paraplegias (HSPs) refer to a group of heterogeneous neurodegenerative diseases characterized by lower limbs spasticity and weakness. So far, over 72 genes have been found to cause HSP (SPG1-SPG72). Among autosomal dominant HSP patients, spastic paraplegia 4 (SPG4/SPAST) gene is the most common pathogenic gene, and atlastin-1 (ATL1) is the second most common one. Here we reported a novel ATL1 mutation in a Chinese spastic paraplegia 3A (SPG3A) family, which expands the clinical and genetic spectrum of ATL1 mutations. CASE SUMMARY A 9-year-old boy with progressive spastic paraplegia accompanied by right hearing loss and mental retardation for five years was admitted to our hospital.Past history was unremarkable. The family history was positive, and his grandfather and mother had similar symptoms. Neurological examinations revealed hypermyotonia in his lower limbs, hyperreflexia in knee reflex, bilateral positive Babinski signs and scissors gait. The results of blood routine test, liver function test, blood glucose test, ceruloplasmin test and vitamin test were all normal. The serum lactic acid level was significantly increased. The testing for brainstem auditory evoked potential demonstrated that the right side hearing was impaired while the left was normal. Magnetic resonance imaging showed mild atrophy of the spinal cord. The gene panel test revealed that the proband carried an ATL1 c.752A>G p.Gln251Arg (p.Q251R) mutation, and Sanger sequencing confirmed the existence of family co-segregation. CONCLUSION We reported a novel ATL1 Q251R mutation and a novel clinical phenotype of hearing loss in a Chinese SPG3A family. 展开更多
关键词 HEREDITARY SPASTIC PARAPLEGIA SPG3A Atlastin-1 (ATL1) gene HEARING loss Case report
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Consensus on the digestive endoscopic tunnel technique 预览
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作者 Ning-Li Chai Hui-Kai Li +45 位作者 En-Qiang Linghu Zhao-Shen Li Shu-Tian Zhang Yu Bao Wei-Gang Chen Philip WY Chiu Tong Dang Wei Gong Shu-Tang Han Jian-Yu Hao Shui-Xiang He Bing Hu1 Bing Hu2 Xiao-Jun Huang Yong-Hui Huang Zhen-Dong Jin Mouen A Khashab James Lau Peng Li Rui Li De-Liang Liu Hai-Feng Liu Jun Liu Xiao-Gang Liu Zhi-Guo Liu Ying-Cai Ma Gui-Yong Peng Long Rong Wei-Hong Sha Pateek Sharma Jian-Qiu Sheng Shui-Sheng Shi Dong Wan Seo Si-Yu Sun Gui-Qi Wang Wen Wang Qi Wu Hong Xu Mei-Dong Xu Ai-Ming Yang Fang Yao Hong-Gang Yu Ping-Hong Zhou Bin Zhang Xiao-Feng Zhang Ya-Qi Zhai 《世界胃肠病学杂志:英文版》 SCIE CAS 2019年第7期744-776,共33页
With the digestive endoscopic tunnel technique(DETT),many diseases that previously would have been treated by surgery are now endoscopically curable by establishing a submucosal tunnel between the mucosa and musculari... With the digestive endoscopic tunnel technique(DETT),many diseases that previously would have been treated by surgery are now endoscopically curable by establishing a submucosal tunnel between the mucosa and muscularis propria(MP).Through the tunnel,endoscopic diagnosis or treatment is performed for lesions in the mucosa,in the MP,and even outside the gastrointestinal(GI)tract.At present,the tunnel technique application range covers the following:(1)Treatment of lesions originating from the mucosal layer,e.g.,endoscopic submucosal tunnel dissection for oesophageal large or circular early-stage cancer or precancerosis;(2)treatment of lesions from the MP layer,per-oral endoscopic myotomy,submucosal tunnelling endoscopic resection,etc.;and(3)diagnosis and treatment of lesions outside the GI tract,such as resection of lymph nodes and benign tumour excision in the mediastinum or abdominal cavity.With the increasing number of DETTs performed worldwide,endoscopic tunnel therapeutics,which is based on DETT,has been gradually developed and optimized.However,there is not yet an expert consensus on DETT to regulate its indications,contraindications,surgical procedure,and postoperative treatment.The International DETT Alliance signed up this consensus to standardize the procedures of DETT.In this consensus,we describe the definition,mechanism,and significance of DETT,prevention of infection and concepts of DETTassociated complications,methods to establish a submucosal tunnel,and application of DETT for lesions in the mucosa,in the MP and outside the GI tract(indications and contraindications,procedures,pre-and postoperative treatments,effectiveness,complications and treatments,and a comparison between DETT and other operations). 展开更多
关键词 DIGESTIVE ENDOSCOPIC TUNNEL technique ENDOSCOPIC SUBMUCOSAL TUNNEL dissection Per-oral ENDOSCOPIC MYOTOMY SUBMUCOSAL TUNNELLING ENDOSCOPIC resection Gastrointestinal tract
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Adaptive multi-resolution Modularity for detecting communities in networks
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作者 Shi Chen Zhi-Zhong Wang +5 位作者 Mei-Hua Bao Liang Tang Ji Zhou Ju Xiang Jian-Ming Li Chen-He Yi 《长沙医学院学报》 2019年第1期1-14,共14页
Community structure is a common topological property of complex networks, which attracted much attention from various fields. Optimizing quality functions for community structures is a kind of popular strategy for com... Community structure is a common topological property of complex networks, which attracted much attention from various fields. Optimizing quality functions for community structures is a kind of popular strategy for community detection, such as Modularity optimization. Here, we introduce a general definition of Modularity, by which several classical(multi-resolution) Modularity can be derived, and then propose a kind of adaptive(multi-resolution) Modularity that can combine the advantages of different Modularity. By applying the Modularity to various synthetic and real-world networks, we study the behaviors of the methods, showing the validity and advantages of the multi-resolution Modularity in community detection. The adaptive Modularity, as a kind of multi-resolution method, can naturally solve the first-type limit of Modularity and detect communities at different scales;it can quicken the disconnecting of communities and delay the breakup of communities in heterogeneous networks;and thus it is expected to generate the stable community structures in networks more effectively and have stronger tolerance against the secondtype limit of Modularity. 展开更多
关键词 Complex NETWORKS COMMUNITY detection MODULARITY MULTI-RESOLUTION
Biomass Characteristics of the Arbor Layer in Different Stands of the Evergreen Broad-Leaved Forest 预览
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作者 ZENG Zhangquan TANG Hong +4 位作者 LI Minghong YANG Rui ZHANG Canming WANG Ying ZENG Xiahui 《景观研究:英文版》 2019年第3期105-106,109共3页
In this paper, the Pinus massoniana forest in the early stage of succession, the coniferous broad-leaved mixed forest in the middle stage of succession, and the evergreen broad-leaved forest in the late stage of succe... In this paper, the Pinus massoniana forest in the early stage of succession, the coniferous broad-leaved mixed forest in the middle stage of succession, and the evergreen broad-leaved forest in the late stage of succession were studied, and the biomass and its spatial distribution characteristics of the tree layer in different succession stages of the ecosystem were discussed. The results showed that the biomass of the arbor layer was the highest in the evergreen broad-leaved forest, which was 292.51 t/ hm2, followed by the coniferous and broad-leaved mixed forest, which was 206.87 t/hm2, and the Pinus massoniana forest, which was 171.76 t/hm2. The biomass of trunks accounted for the largest proportion in the total biomass of the arbor layer, which reduced from the Pinus massoniana forest to the evergreen broad-leaved forest. The proportion of the biomass of roots in the total biomass of the arbor layer increased from the Pinus massoniana forest to the evergreen broad-leaved forest. The biomass of the diameter class above 20 cm in the Pinus massoniana forest, the coniferous and broad-leaved mixed forest and the evergreen broad-leaved forest accounted for a large proportion of total biomass. 展开更多
关键词 EVERGREEN broad-leaved FOREST Biomass of the ARBOR LAYER Mid-subtropics SUCCESSION stage
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Effects of prescribed burning on carbon accumulation in two paired vegetation sites in subtropical China 预览
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作者 Yuanqi Chen Jianbo Cao +2 位作者 Lixia Zhou Feng Li Shenglei Fu 《森林生态系统:英文版》 CSCD 2019年第3期210-218,共9页
Background: Prescribed burning is a common practice of site preparation before afforestation in subtropical forests. However, the effects of prescribed burning on carbon (C) dynamics of an ecosystem are poorly underst... Background: Prescribed burning is a common practice of site preparation before afforestation in subtropical forests. However, the effects of prescribed burning on carbon (C) dynamics of an ecosystem are poorly understood. Therefore, a Eucalyptus urophylla plantation (EU) and a naturally recovered shrubland (NS), each treated with prescribed burning and no burning were examined in subtropical China. Methods: Biomass of trees and shrubs in the 1st, 3nd, 4th, and 6th year after treatments were estimated by quadrat survey and allometric equations. Biomass of herbs and forest floors were estimated by harvest method. Plant biomass C storage was calculated by plant biomass multiplying by its C concentration. Soil organic C (SOC) storage in the 6th year after treatments was estimated by SOC concentration multiplying by soil bulk density and soil volumes. Results: Tree biomass C storage was significantly higher in the burned EU (BEU) than in the unburned EU (UEU) in the 1st year after treatments, yet the difference decreased over time. Conversely, tree biomass C storage was lower in the burned NS (BNS) than in the unburned NS (UNS), although the difference was not significant. However, in the 6th year after treatments, the total plant biomass C storage was 14.56% higher in the BEU than that in the UEU, and 59.93% higher in the BNS than that in the UNS, respectively, although the significant difference was only found between UNS and BNS. In addition, neither SOC storage at 0-20 cm nor ecosystem C storage in either the EU or NS was significantly affected by prescribed burning. Conclusions: Prescribed burning has little impact on overall C storage of forest ecosystems, we consider that prescribed burning may be an option for forest site preparation regarding plant biomass C accumulation. 展开更多
关键词 PRESCRIBED fire REFORESTATION Plant BIOMASS CARBON Soil ORGANIC CARBON FOREST management
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Tunable Schottky barrier width and enormously enhanced photoresponsivity in Sb doped SnS2 monolayer
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作者 Junchi Liu Xiao Liu +9 位作者 Zhuojun Chen Lili Miao Xingqiang Liu Bo Li Liming Tang Keqiu Chen Yuan Liu Jingbo Li Zhongming Wei Xidong Duan 《纳米研究:英文版》 SCIE EI CAS CSCD 2019年第2期463-468,共6页
Doping, which is the intentional introducti on of impurities into a material, can improve the metal-semiconductor interface by reducing Schottky barrier width. Here, we prese nt high-quality two-dime nsional SnS2 nano... Doping, which is the intentional introducti on of impurities into a material, can improve the metal-semiconductor interface by reducing Schottky barrier width. Here, we prese nt high-quality two-dime nsional SnS2 nano sheets with well-controlled Sb dopi ng concen tration via direct vapor growth approach and following micromechanical cleavage process. X-ray photoelectro n spectroscopy (XPS) measureme nt dem on strates that Sb contents of the doped samples are approximately 0.22%, 0.34% and 1.21%, respectively, and doping in duces the upward shift of the Fermi level with respect to the pristi ne SnS2. Tran smissio n electro n microscopy (TEM) characterizatio n exhibits that Sb-doped SnS2 nano sheets have a high-quality hexagonal symmetry structure and Sb element is uniformly distributed in the nano sheets. The phototra nsistors based on the Sb-doped SnS2 mono layers show n-type behavior with high mobility which is one order of magn itude higher than that of pristi ne SnS2 phototra nsistors. The photorespo nsivity and exter nal quantum efficiency (EQE) of Sb-S nS2 mono layers phototra nsistors are approximately three orders of magnitude higher than that of pristine SnS2 phototransistor. The results suggest that the method of reducing Shottky barrier width to achieve high mobility and photoresp on sivity is effective, and Sb-doped SnS2 mono layer has significant potential in future nanoelectronic and optoelectronic applications. 展开更多
关键词 two-dimensional DOPING SCHOTTKY barrier WIDTH SnS2 OPTOELECTRONICS
Recent advances in controlling the crystallization of two-dimensional perovskites for optoelectronic device
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作者 Shi-Qiang Luo Ji-Fei Wang +1 位作者 Bin Yang Yong-Bo Yuan 《物理学前沿:英文版》 SCIE CSCD 2019年第5期1-17,共17页
Though three-dimensional (3D) organic inorganic halide perovskites (OIHP) is very promising for low cost and distributed PV generation,the stability issue of 3D OIHP is still a problem for its commer-cialization.Two-d... Though three-dimensional (3D) organic inorganic halide perovskites (OIHP) is very promising for low cost and distributed PV generation,the stability issue of 3D OIHP is still a problem for its commer-cialization.Two-dimensional (2D) perovskites,protected by periodic organic ligands,is promising due to its excellent optoelectronic property and superior stability.However,2D perovskitc is anisotropic in its crystal structure and optoelectronic properties,and the resulted film is often a mixture of different phase.So,methods to manipulate 2D perovskitc crystal orientation and its phase separation are vital.In this review,the major advances on the composition engineering,crystal orientation,phase separa-tion,and inlerfaeial capping are summarized.Besides,efforts on understanding the formation process of 2D perovskitc crystal arc also discussed,which is important for making full use of 2D perovskitc in functional optoelectronic devices. 展开更多
关键词 OPTOELECTRONIC devices PEROVSKITE SOLAR cells NANOSCALE materials chemical vapor DEPOSITION
High temperature mechanical retention characteristics and oxidation behaviors of the MoSi2(Cr5Si3)–RSiC composites prepared via a PIP-AAMI combined process
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作者 Peng-zhao GAO Lei CHENG +2 位作者 Zheng YUAN Xiao-pan LIU Han-ning XIAO 《先进陶瓷(英文版)》 CSCD 2019年第2期196-208,共13页
In the present paper,MoSi2(Cr5Si3)–RSiC composites were prepared via a combination of precursor impregnation pyrolysis(PIP) and MoSi2-Si-Cr alloy active melt infiltration(AAMI) process. Composition, microstructure, m... In the present paper,MoSi2(Cr5Si3)–RSiC composites were prepared via a combination of precursor impregnation pyrolysis(PIP) and MoSi2-Si-Cr alloy active melt infiltration(AAMI) process. Composition, microstructure, mechanical retention characteristics, and oxidation behaviors of the composites at elevated temperature were studied. X-ray diffraction(XRD) pattern confirms that the composites mainly compose of 6 H–SiC, hexagonal MoSi2, and tetragonal Cr5Si3. Scanning electron microscopy(SEM) image reveals that nearly denseMoSi2(Cr5Si3)–RSiC composites exhibiting three-dimensionally(3D) interpenetrated network structure are obtained when infiltrated at 2173 K, and the interface combination of the composites mainly depends on the composition ratio of infiltrated phases. Oxidation weight gain rate of the composites is much lower than that of RSiC matrix, where MoSiCr2 possesses the lowest value of 0.1630 mg×cm-2, about 78% lower than that of RSiC after oxidation at 1773 K for 100 h. Also, it possesses the highest mechanical values of 139.54 MPa(flexural strength σf and RT) and 276.77 GPa(elastic modulus Ef and RT), improvement of 73.73% and 29.77% as compared with that of RSiC, respectively. Mechanical properties of the composites increase first and then decrease with the extension of oxidation time at 1773 K, due to the cooperation effect of surface defect reduction via oxidation reaction and thermal stress relaxation in the composites, crystal growth, and thickness increase of the oxide film. Fracture toughness of MoSiCr2 reaches 2.24 MPa·m1/2(1673 K), showing the highest improvement of 31.70% as compared to the RT value. 展开更多
关键词 MoSi2(Cr5Si3)–RSiC composites precursor IMPREGNATION pyrolysis and MoSi2-Si-Cr alloy active melt infiltration (PIP-AAMI) high temperature MECHANICAL characteristic oxidation behavior
Comparison of the Morphology,Structures and Mechanical Properties of Teleost Fish Scales Collected from New Zealand
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作者 Deju Zhu Chaohui Zhang +1 位作者 Peng Liu Laith A.Jawad 《仿生工程学报:英文版》 SCIE EI CSCD 2019年第2期328-336,共9页
The mechanical properties and structures of fish scales have generated considerable research interest,however,comparative studies for different fish scales from difl^rent water regions have not been reported.In this p... The mechanical properties and structures of fish scales have generated considerable research interest,however,comparative studies for different fish scales from difl^rent water regions have not been reported.In this paper,the surface morphologies,hierarchical structures and mechanical properties of four kinds of fish scales collected from freshwater,shallow sea,and deep sea in New Zealand are investigated.The results indicate that the surface morphologies of those fish scales are similar at ventro-lateral,dorso-lateral and anterior locations,and the hierarchical structures of those fish scales all consist of two layers:a bone layer and a collagen layer composed of collagen fibrils.However,the spiral angles of the collagen lamellaes of different scales are different.The largest are Mugil cephalus scales,while the smallest are Cyprinus carpio scales.Comparing the mechanical behaviors of those fish scales,the tensile strength of Carassius auratus scales is the largest,but the ductility is the lowest.Pristipomoides sieboldii scales have the best ductility.Further,the relationship between hierarchical structures and mechanical properties of fish scales is discussed.It is found that the spiral angles of the collagen lamellaes and bond/collagen thickness ratio both have a great influence on the mechanical properties of fish scales. 展开更多
关键词 MORPHOLOGY HIERARCHICAL structure MECHANICAL property FISH SCALE water region
5-aza-2’-deoxycytidine in the regulation of antioxidant enzymes in retinal endothelial cells and rat diabetic retina
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作者 Man-Yun Xie Yan Yang +2 位作者 Ping Liu Yan Luo Shi-Bo Tang 《国际眼科杂志:英文版》 SCIE CAS 2019年第1期1-7,共7页
AIM: To investigate the roles of a DNA methyltransferase(DNMT) inhibitor 5-aza-2’-deoxycytidine(5-aza-dC) in the regulation of antioxidant enzymes in diabetic retinopathy(DR) models. METHODS: DNMTs expressions and ac... AIM: To investigate the roles of a DNA methyltransferase(DNMT) inhibitor 5-aza-2’-deoxycytidine(5-aza-dC) in the regulation of antioxidant enzymes in diabetic retinopathy(DR) models. METHODS: DNMTs expressions and activity, and changes of two key antioxidant enzymes in DR, MnSOD(encoded by SOD2 gene) and glutathione S-transferase theta 1(GSTT1), were quantified in the isolated human retinal endothelial cells(HRECs) exposed to high glucose(HG) with or without 5-aza-dC treatment. The downstream exacerbating factors including vascular endothelial growth factor(VEGF), intercellular adhesion molecule 1(ICAM-1) and matrix metalloproteinase 2(MMP2), which are implicated in the pathogenesis of DR and closely related to oxidative stress were also analyzed. The key parameters were confirmed in the retina from streptozotocin(STZ) diabetic rats. RESULTS: DNMTs expression and DNMT activity was induced in HRECs exposed to HG. Hyperglycemia decreased MnSOD and GSTT1 expression. 5-aza-dC administration effectively suppressed DNMTs expression and activity and reversed the MnSOD and GSTT1 expression under HG condition. VEGF, ICAM-1 and MMP2 induced by HG were also suppressed by 5-aza-dC treatment. Similar results were observed in the retina from STZ diabetic rats. CONCLUSION: Our findings suggest that DNA methylation may serves as one of the mechanisms of antioxidant defense system disruption in DR progression. Modulation of DNA methylation using pharmaceutic means such as DNMT inhibitors could help maintain redox homeostasis and prevent further progression of DR. 展开更多
关键词 DNA METHYLATION diabetic model 5-AZA-DC oxidative stress inflammation human RETINAL endothelial cells RAT
Effects of restrictions on maternal feed intake on the immune indexes of umbilical cord blood and liver Toll-like receptor signaling pathways in fetal goats during pregnancy 预览
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作者 Wenxun Chen Qiongxian Yan +2 位作者 Hong Yang Xiaoling Zhou Zhiliang Tan 《畜牧与生物技术杂志:英文版》 SCIE CAS CSCD 2019年第3期736-744,共9页
Background: Liver has important immune function during fetal development and after birth.However,the effect of maternal malnutrition on immune function of the fetal liver is rarely reported.In this study,twelve pregna... Background: Liver has important immune function during fetal development and after birth.However,the effect of maternal malnutrition on immune function of the fetal liver is rarely reported.In this study,twelve pregnant goats(Xiangdong black goat,at d 45 of gestation) were assigned to the control group(fed 100% of nutritional requirements) and the restriction group(fed 60% of the intake of the control group) during gestation from d 55 to100.Fetal goats were harvested at d 100 of gestation and immune indexes and amino acid profiles of the umbilical cord blood and liver Toll-like receptors(TLRs) signaling pathways were measured.Results: Maternal body weight in the restriction group was lower than the control group(P < 0.05).Maternal feed intake restriction decreased(P < 0.05) heart weight,heart index,alkaline phosphatase and serum amyloid protein A in the umbilical cord blood(UCB).Moreover,only histidine was decreased in the restricted group(P = 0.084),and there were no differences in other amino acids contents in the UCB between the two groups(P > 0.05).The TLR2 and TLR4 mRNA expression in the fetal liver in the restriction group was greater(P < 0.05) than that in the control group.Furthermore,the mRNA expression levels of myeloid differentiation primary response 88(MyD88),TNF receptor associated factor 6,nuclear factor kappa B subunit 1,NFKB inhibitor alpha,IFN-β,TGF-β,TNF-α and IL-1β in the restricted group were upregulated(P < 0.05),and the expression of TLR3(P = 0.099) tended to be higher in the restricted group.However,protein levels of TLR2,TLR4,IκBα,phosphorylated IκBα,phosphorylated IκBα/total IκBα,TRIF and MyD88 were not affected(P > 0.05) by maternal intake restriction.Conclusions: These results revealed that the restriction of maternal feed intake influenced the development of heart and hepatic protein synthesis at the acute phase of fetal goats and upregulated the mRNA expression of genes involved in MyD88-dependent signaling pathways and of target cytokines. 展开更多
关键词 Feed INTAKE RESTRICTION FETAL goats Immune cell LIVER TLRs signaling pathway
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Lotus seed skin proanthocyanidin extract exhibits potent antioxidant property via activation of the Nrf2-ARE pathway
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作者 Tao Li Qili Li +9 位作者 Weiguo Wu Yong Li De-xing Hou Hua Xu Baodong Zheng Shaoxiao Zeng Yang Shan Xiangyang Lu Fangming Deng Si Qin 《生物化学与生物物理学报:英文版》 SCIE CAS CSCD 2019年第1期31-40,共10页
Lotus seed is well known as traditional food and medicine,but its skin is usually discarded.Recent studies have shown that lotus seed skin contains a high concentration of proanthocyanidins that have multi-functions,s... Lotus seed is well known as traditional food and medicine,but its skin is usually discarded.Recent studies have shown that lotus seed skin contains a high concentration of proanthocyanidins that have multi-functions,such as antioxidation,anti-inflammation,and anti-cancer effects.In the present study,we aimed to isolate and purify the proanthocyanidins from lotus seed skin by acetone extraction and rotary evaporation,identify their chemical structures by HPLC-MS-MS and NMR,and further investigate the antioxidant properties of the extract purified by macroporous resin (PMR) from lotus seed skin both in vitro and in vivo.The results showed that PMR mainly contained oligomeric proanthocyanidins,especially dimeric procyanidin B1 (PB1),procyanidin B2 and procyanidin B4.Although it had limited ability to directly scavenge radicals in vitro,PMR could significantly enhance the expressions of antioxidant proteins via activation of nuclear factory-related factor 2 (Nrf2)-antioxidant response element (ARE) pathway in HepG2 cells.Molecular data revealed that PB1,a major component in PMR,stabilized Nrf2 by inhibiting the ubiquitination of Nrf2,which led to subsequent activation of the Nrf2-ARE pathway,including the enhancements of Nrf2 nuclear translocation,Nrf2-ARE binding and ARE transcriptional activity.Moreover,the in vivo results in high fat diet-induced mice further verified the powerful antioxidant property of PMR.These results revealed that lotus seed skin is a promising resource for functional food development. 展开更多
关键词 lotus SEED SKIN EXTRACT proanthocyanidin Nrf2-ARE PATHWAY antioxidant activity
Research on Mobile Internet Mobile Agent System Dynamic Trust Model for Cloud Computing 预览
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作者 Weijin Jiang Yang Wang +3 位作者 Yirong Jiang Jiahui Chen Yuhui Xu Lina Tan 《中国通信:英文版》 SCIE CSCD 2019年第7期174-194,共21页
This paper analyzes the reasons for the formation of security problems in mobile agent systems, and analyzes and compares the security mechanisms and security technologies of existing mobile agent systems from the per... This paper analyzes the reasons for the formation of security problems in mobile agent systems, and analyzes and compares the security mechanisms and security technologies of existing mobile agent systems from the perspective of blocking attacks. On this basis, the host protection mobile agent protection technology is selected, and a method to enhance the security protection of mobile agents (referred to as IEOP method) is proposed. The method first encrypts the mobile agent code using the encryption function, and then encapsulates the encrypted mobile agent with the improved EOP protocol IEOP, and then traces the suspicious execution result. Experiments show that using this method can block most malicious attacks on mobile agents, and can protect the integrity and confidentiality of mobile agents, but the increment of mobile agent tour time is not large. 展开更多
关键词 MOBILE internet CLOUD COMPUTING MOBILE agent system SUBJECTIVE TRUST dynamic TRUST management
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Characteristics of Shale Reservoir and Sweet Spot Identification of the Lower Cambrian Niutitang Formation in Northwestern Hunan Province,China 预览
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作者 QIN Mingyang CAO Zheng +3 位作者 GUO Jianhua HUANG Yanran SUN Lianpu DONG Li 《地质学报:英文版》 SCIE CAS CSCD 2019年第3期573-587,共15页
The accumulation and productivity of shale gas are mainly controlled by the characteristics of shale reservoirs;study of these characteristics forms the basis for the shale gas exploitation of the Lower Cambrian Niuti... The accumulation and productivity of shale gas are mainly controlled by the characteristics of shale reservoirs;study of these characteristics forms the basis for the shale gas exploitation of the Lower Cambrian Niutitang Formation(Fm),Southern China.In this study,core observation and lithology study were conducted along with X-ray diffraction(XRD)and electronic scanning microscopy(SEM)examinations and liquid nitrogen(N2)adsorption/desorption and CH4 isothermal adsorption experiments for several exploration wells in northwestern Hunan Province,China.The results show that one or two intervals with high-quality source rocks(TOC>2 wt%)were deposited in the deep-shelf facies.The source rocks,which were mainly composed of carbonaceous shales and siliceous shales,had high quartz contents(>40 wt%)and low clay mineral(<30 wt%,mainly illites)and carbonate mineral(<20 wt%)contents.The SEM observations and liquid nitrogen(N2)adsorption/desorption experiments showed that the shale is tight,and nanoscale pores and microscale fractures are well developed.BJH volume(VBJH)of shale ranged from 2.144×10^-3 to 20.07×10^-3 cm^3/g,with an average of 11.752×10^-3 cm3/g.Pores mainly consisted of opened and interconnected mesopores(2–50 nm in diameter)or macropores(>50 nm in diameter).The shale reservoir has strong adsorption capacity for CH4.The Langmuir volume(VL)varied from 1.63 to 7.39 cm^3/g,with an average of 3.95 cm^3/g.The characteristics of shale reservoir are controlled by several factors:(1)A deep muddy continental shelf is the most favorable environment for the development of shale reservoirs,which is controlled by the development of basic materials.(2)The storage capacity of the shale reservoir is positively related to the TOC contents and plastic minerals and negatively related to cement minerals.(3)High maturity or overmaturity leads to the growth of organic pores and microfractures,thereby improving the reservoir storage capacity.It can be deduced that the high percentage of residual gas in Niutitang Fm results from 展开更多
关键词 NORTHWESTERN Hunan Province Niutitang Formation RESERVOIR CHARACTERISTICS control factors sweet SPOTS IDENTIFICATION
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Demographic Characteristics and Environmental Risk Factors Exposure of Birth Defects in Pregnant Women: A Population-based Study 预览
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作者 LIN Hong LUO Mi Yang +4 位作者 LUO Jia You ZENG Rong LI Ya Mei DU Qi Yun FANG Jun Qun 《生物医学与环境科学:英文版》 SCIE CAS CSCD 2019年第1期51-57,共7页
Worldwide, the incidence of birth defects in low-income countries is 6.42%, while in middle-income and high-income countries it is 5.57% and 4.72%, respectively;approximately 303, 000 newborns die from birth defects e... Worldwide, the incidence of birth defects in low-income countries is 6.42%, while in middle-income and high-income countries it is 5.57% and 4.72%, respectively;approximately 303, 000 newborns die from birth defects each year. In China, the incidence of birth defects is about 5.6%, and around 8.14 million people have congenital disabilities, accounting for 9.6% of total disabled people[1]. Birth defect remains a major clinical and public health challenge because of its high fatality rate and protracted and severe sequela. 展开更多
关键词 BIRTH DEFECTS demographics ENVIRONMENTAL RISK FACTORS
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Electrospun CoSe@N-doped carbon nanofibers with highly capacitive Li storage 预览
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作者 Jiandong Liu Jiaojiao Liang +1 位作者 Caiyun Wang Jianmin Ma 《能源化学:英文版》 SCIE EI CAS CSCD 2019年第6期160-166,共7页
One-dimensional nano-structured materials have attracted attention due to its unique properties afforded such as the across-linked structures and large aspect ratios.In this work,one-dimensional CoSe@N-doped carbon na... One-dimensional nano-structured materials have attracted attention due to its unique properties afforded such as the across-linked structures and large aspect ratios.In this work,one-dimensional CoSe@N-doped carbon nanofibers(CoSe@NCNFs)are successfully by combining the techniques of electrospinning and annealing.Selenium powder are directly dispersed in the polyacrylonitrile/N,N-Dimethylformamide(DMF)solution containing cobalt salt to form the product.The performance of these materials was investigated in Li-ion batteries after the annealing at different temperatures.The Co Se@NC nanofibers annealed at 550℃(CoSe@NC-550)and displayed excellent storage properties,affording a high capacity of 796 m Ah·g-1at a current density of 1 A·g^-1 for 100 cycles.Moreover,it is confirmed that the pseudocapacitive contribution of CoSe@NC-550 is up to 72.8%at the scan rate of 1 mV/s through the cyclic voltammetry analysis. 展开更多
关键词 CoSe ANODE NANOFIBERS ELECTROSPINNING LI-ION batteries
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Prevalence of amblyopia among preschool children in central south China
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作者 Yun-Ping Li Meng-Wen Zhou +4 位作者 Susan H Forster Si-Ying Chen Xin Qi Hui-Ming Zhang Jing Luo 《国际眼科杂志:英文版》 SCIE CAS 2019年第5期820-825,共6页
AIM: To determine the prevalence and factors associated with amblyopia among children aged 30-83 mo in central south of China.METHODS: A population-based, cross-sectional study was conducted in children aged 30-83 mo ... AIM: To determine the prevalence and factors associated with amblyopia among children aged 30-83 mo in central south of China.METHODS: A population-based, cross-sectional study was conducted in children aged 30-83 mo in Changsha(an urban city) and Zhangjiajie(a rural area) in central south of China. Clinical examinations including ocular alignment, ocular motility, visual acuity(VA), prism cover test, cycloplegic refraction, slit lamp examination and fundus examination were performed by trained study ophthalmologists and optometrists. Unilateral amblyopia was defined as a 2-line difference between eyes with VA<20/32 in the worse eye and with coexisting anisometropia [≥1.00 D spherical eutivalent(SE) for hyperopia, ≥3.00 D SE for myopia, and ≥1.50 D for astigmatism], strabismus, or past or present visual axis obstruction. Bilateral amblyopia was defined as VA in both eyes <20/40(≥ 48-month-old) and <20/50(< 48-month-old), with coexisting hyperopia ≥4.00 D SE, myopia ≤-6.00 D SE, and astigmatism ≥2.50 D, or past or present visual axis obstruction.RESULTS: There were 8042 children enrolled and 7713 children were screened. The amblyopia prevalence in children aged 30-83 mo was 1.09%(95% confidence interval, 0.86%-1.35%) with no age(P=0.81), gender(P=0.46) or area distribution(P=0.93) differences. Of these, 0.68% were unilateral cases and 0.41% were bilateral cases. Underlying causes included anisometropia(40%), binocular refractive error(36%), strabismus(14%) and deprivation(10%). Hyperopia combined with astigmatism was the frequent refractive error for ametropic and anisometropic amblyopia.CONCLUSION: In this rural and urban Chinese population, 1.09% of children with 30-83 mo of age had amblyopia, a prevalence rate similar to that of many other studies. Anisometropia and refractive error are the most common causes of unilateral and bilateral amblyopia respectively. 展开更多
关键词 AMBLYOPIA PREVALENCE RURAL URBAN Chinese
Broadband mid-infrared nonlinear optical modulator enabled by gold nanorods:towards the mid-infrared regime
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作者 BIN HUANG ZHE KANG +8 位作者 JIE LI MINGYI LIU PINGHUA TANG LILI MIAO CHUJUN ZHAO GUANSHI QIN WEIPING QIN SHUANGCHUN WEN PARAS N.PRASAD 《光子学研究:英文版》 CSCD 2019年第6期699-704,共6页
Mid-infrared pulsed lasers operating around the 3 μm wavelength regime are important for a wide range of applications including sensing, spectroscopy, imaging, etc. Despite the recent advances in technology, the lack... Mid-infrared pulsed lasers operating around the 3 μm wavelength regime are important for a wide range of applications including sensing, spectroscopy, imaging, etc. Despite the recent advances in technology, the lack of a nonlinear optical modulator operating in the mid-infrared regime remains a significant challenge. Here, we report the third-order nonlinear optical response of gold nanorods(GNRs) ranging from 800 nm to the mid-infrared regime(2810 nm) enabled by their size and overlapping behavior-dependent longitudinal surface plasmon resonance. In addition, we demonstrate a wavelength-tunable Er3+-doped fluoride fiber laser modulated by GNRs, which can deliver pulsed laser output, with the pulse duration down to 533 ns, tunable wavelength ranging from 2760.2 to 2810.0 nm, and spectral 3 d B bandwidth of about 1 nm. The experimental results not only validate the GNRs’ robust mid-infrared nonlinear optical response, but also manifest their application potential in high-performance broadband optoelectronic devices. 展开更多
关键词 optical MODULATOR MID-INFRARED REGIME
Endoscopic mucosal resection of a bile duct polyp: A case report 预览
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作者 Shu Yang Li Yang +1 位作者 Xiang-Yang Wang Yu-Ming Yang 《世界临床病例杂志》 2019年第18期2864-2870,共7页
BACKGROUND Bile duct polyps are difficult to diagnose and are usually excised by open abdominal surgery or snare polypectomy using choledochoscopy via the T-tube sinus tract. However, these two resection methods requi... BACKGROUND Bile duct polyps are difficult to diagnose and are usually excised by open abdominal surgery or snare polypectomy using choledochoscopy via the T-tube sinus tract. However, these two resection methods require the surgeon to open the abdomen and cut the bile duct to place the “T” tube. Moreover, simple snare polypectomy, without submucosal injection, can only remove pedunculated polyps and not flat polyps. Therefore, a new method is required for the excision of bile duct polyps, including flat polyps. CASE SUMMARY A 63-year-old woman was hospitalized following epigastric pain lasting a month. She had a 30-year history of cholelithiasis and had undergone cholecystectomy because of cholecystolithiasis, and had undergone cholangiolithotomy twice due to choledocholithiasis. Computed tomography (CT) and magnetic resonance imaging showed a communication between the bile duct and duodenal bulb. Inside the communication, CT showed a high-density shadow which was a hypointense lesion in T2 weighted image. The lesion showed no enhancement in T1 weighted image contrast enhanced. Gastroscopy revealed an incarcerated bile duct stone in the anterior wall of the duodenal bulb, which was removed with a basket under gastroscopy. Thereafter, a choledochoduodenal fistula was revealed. Finally, a flat polyp was detected in the lower part of the common bile duct and was removed by endoscopic mucosal resection (EMR) through the fistula. To our knowledge, this is the first reported case of the removal of a bile duct polyp using EMR. CONCLUSION EMR is a safe, effective, and low-cost method for the resection of all bile duct polyps. 展开更多
关键词 Case report Cholangiolithiasis BILE DUCT POLYP ENDOSCOPIC MUCOSAL RESECTION
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