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MicroRNAs in blood and cerebrospinal fluid as diagnostic biomarkers of multiple sclerosis and to monitor disease progression 预览
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作者 Bridget Martinez Philip V.Peplow 《中国神经再生研究:英文版》 SCIE CAS CSCD 2020年第4期606-619,共14页
Multiple sclerosis is a chronic autoimmune disease of the central nervous system.It is the main cause of non-traumatic neurological disability in young adults.Multiple sclerosis mostly affects people aged 20–50 years... Multiple sclerosis is a chronic autoimmune disease of the central nervous system.It is the main cause of non-traumatic neurological disability in young adults.Multiple sclerosis mostly affects people aged 20–50 years;however,it can occur in young children and much older adults.Factors identified in the distribution of MS include age,gender,genetics,environment,and ethnic background.Multiple sclerosis is usually associated with progressive degrees of disability.The disease involves demyelination of axons of the central nervous system and causes brain and spinal cord neuronal loss and atrophy.Diagnosing multiple sclerosis is based on a patient’s medical history including symptoms,physical examination,and various tests such as magnetic resonance imaging,cerebrospinal fluid and blood tests,and electrophysiology.The disease course of multiple sclerosis is not well correlated with the biomarkers presently used in clinical practice.Blood-derived biomarkers that can detect and distinguish the different phenotypes in multiple sclerosis may be advantageous in personalized treatment with disease-modifying drugs and to predict response to treatment.The studies reviewed have shown that the expression levels of a large number of miRNAs in peripheral blood,serum,exosomes isolated from serum,and cerebrospinal fluid are altered in multiple sclerosis and can distinguish the disease phenotypes from each other.Further studies are warranted to independently validate these findings so that individual or pairs of miRNAs in serum or cerebrospinal fluid can be used as potential diagnostic markers for adult and pediatric multiple sclerosis and for monitoring disease progression and response to therapy. 展开更多
关键词 clinically isolated syndrome CSF disease PROGRESSION EXOSOMES humans microRNA multiple SCLEROSIS PERIPHERAL blood PHENOTYPES serum
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某框架结构教学楼隔震设计方法研究 预览
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作者 王云波 崔桐 《山西建筑》 2019年第15期30-31,共2页
某中学框架结构教学楼,抗震设防烈度为8度(0.2g),根据现行规范要求需进行隔震设计。通过分析该建筑的隔震设计方案,介绍了该建筑隔震设计中结构设计方法和控制要点,经过隔震设计后,该建筑抗震性能良好,满足规范抗震要求,可为类似的民用... 某中学框架结构教学楼,抗震设防烈度为8度(0.2g),根据现行规范要求需进行隔震设计。通过分析该建筑的隔震设计方案,介绍了该建筑隔震设计中结构设计方法和控制要点,经过隔震设计后,该建筑抗震性能良好,满足规范抗震要求,可为类似的民用公共建筑基础隔震设计、施工提供参考。 展开更多
关键词 教学楼 框架结构 隔震设计
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Reduced β2-GPI is associated with increased platelet aggregation and activation in patients with prolonged isolated thrombocytopenia after allo-HSCT
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作者 Haixia Fu Jingzhong Zhao +8 位作者 Lanping Xu Kaiyan Liu Yu Wang Huan Chen Wei Han Jingzhi Wang Fengrong Wang Xiaojun Huang Xiaohui Zhang 《中国科学:生命科学英文版》 SCIE CAS CSCD 2019年第7期921-929,共9页
We aimed to measure platelet function and its relationship with β2-GPI in prolonged isolated thrombocytopenia(PT) after allogeneic hematopoietic stem cell transplantation(allo-HSCT).Fifty-six patients with PT and 60 ... We aimed to measure platelet function and its relationship with β2-GPI in prolonged isolated thrombocytopenia(PT) after allogeneic hematopoietic stem cell transplantation(allo-HSCT).Fifty-six patients with PT and 60 allo-HSCT recipients without PT(non-PT controls) were enrolled.Platelet aggregation and activation,β2-GPI and anti-β2-GPI antibody levels,vWF antigen,and vWF activity were analyzed.The effect of β2-GPI on platelet aggregation was also measured ex vivo.Results showed that ADP-induced platelet aggregation significantly increased(39%±7.5% vs.23%±8.5%,P=0.032),and the platelet expression of both CD62 p(33.6%±11.6% vs.8.5%±3.5%,P<0.001) and PAC-1(42.4%±7.6% vs.6.8%±2.2%,P<0.001) was significantly higher in patients with PT than in those without PT.Significantly lower β2-GPI levels(164.2±12 μg m L^-1 vs.234.2±16 μg mL^-1,P<0.001),higher anti-β2-GPI IgG levels(1.78±0.46 U mL^-1 vs.0.94±0.39 U mL^-1,P<0.001),and increased vWF activity(133.06%±30.50% vs.102.17%±25.90%,P<0.001) were observed in patients with PT than in those without PT.Both ADPinduced platelet aggregation(n=116,r^2=-0.5042,P<0.001) and vWF activity(n=116,r^2=-0.2872,P<0.001) were negatively correlated with β2-GPI levels.In summary,our data suggested that platelet aggregation and activation were significantly higher in patients with PT than in those without PT,which might be associated with reduced β2-GPI levels.The reduced β2-GPI levels might be due to the existence of anti-β2-GPI IgG. 展开更多
关键词 β2-GPI hematopoietic stem cell transplantation PROLONGED ISOLATED THROMBOCYTOPENIA PLATELET aggregation PLATELET ACTIVATION
Insight into the Relationship Between Local Coordination of Isolated Pt Atoms and Chemical Reactivity 预览
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作者 ZHAO Ziyan ZHOU Ying 《材料导报》 EI CAS CSCD 北大核心 2019年第14期2281-2282,共2页
The supported isolated Pt atoms(Pt iso)and other rare metals have attracted intensive concern due to their maximized metal utilization efficiency,unique reactivity or selectivity,connection to organometallic catalysis... The supported isolated Pt atoms(Pt iso)and other rare metals have attracted intensive concern due to their maximized metal utilization efficiency,unique reactivity or selectivity,connection to organometallic catalysis and the potential for making well-defined active sites[1-3].As catalytic active sites,oxide-supported isolated Pt-group metal atoms are well known for their unique reactivity and efficient metal utilization[4-6].Even continuous efforts have been made,it is still challenging to characterize the intrinsic ca-talytic activity of these dispersed active sites on oxide supports at a level that relates local electronic and geometric structure to function,because of their atomic dispersion,heterogeneity in the local coordination,dynamic changes in local coordination under reactive environments and low loading of metal[7-9]. 展开更多
关键词 Relationship BETWEEN LOCAL COORDINATION ISOLATED PT ATOMS Chemical Reactivity
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藤黄微球菌Rpf因子对土壤细菌可培养物种分离效果的影响 预览
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作者 李云琪 王宇辉 +3 位作者 李小锦 孙健鹏 景凤霞 张秀敏 《河北大学学报:自然科学版》 CAS 北大核心 2019年第1期63-68,共6页
通过培养基添加藤黄微球菌Rpf因子对3份土壤样品中的细菌进行分离以了解藤黄微球菌Rpf因子对细菌可培养物种多样性的影响.通过在改良的VL55培养基中添加藤黄微球菌Rpf因子,对采自河北涞水县上港村、青海三江源和云南无量山3个地区的3份... 通过培养基添加藤黄微球菌Rpf因子对3份土壤样品中的细菌进行分离以了解藤黄微球菌Rpf因子对细菌可培养物种多样性的影响.通过在改良的VL55培养基中添加藤黄微球菌Rpf因子,对采自河北涞水县上港村、青海三江源和云南无量山3个地区的3份土壤样品进行细菌的分离,并对所分离菌株进行16S rRNA基因序列系统发育分析,分析培养基添加藤黄微球菌Rpf因子对土壤中可培养细菌物种分离效果的影响.结果显示:河北土壤中不添加Rpf因子的对照组分离得到5个属,添加Rpf因子的实验组分离得到8个属;青海土壤中对照组分离得到2个属,实验组分离得到6个属;云南土壤中对照组分离得到6个属,实验组分离得到8个属.表明添加藤黄微球菌Rpf因子的实验组分离得到的微生物物种较对照组丰富.其中,青海三江源土壤中分离得到的菌株HBUM200161与多食鞘氨醇杆菌( Sphingobacterium multivorum )IAM14316 T亲缘关系最近,16S rRNA基因序列相似性为97.93%,可能为鞘氨醇杆菌属( Sphingobacterium )潜在的新种. 展开更多
关键词 藤黄微球菌 Rpf 细菌 分离
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Hidden correlation of the effect mechanism on chronic gastritis treated with ginger-isolated moxibustion at different single acupoints
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作者 顾俊薇 杨旭明 +4 位作者 李琪 顾沐恩 吴梦蝶 曹淑菲 李璟 《世界针灸杂志:英文版》 CSCD 2019年第1期48-54,共7页
Objective:To observe the differences in the effects and mechanisms on chronic gastritis treated by gingerisolated moxibustion at Zusanli(足三里ST 36)and Neiguan(内关PC 6).Methods:A total of 60 eligible patients of chr... Objective:To observe the differences in the effects and mechanisms on chronic gastritis treated by gingerisolated moxibustion at Zusanli(足三里ST 36)and Neiguan(内关PC 6).Methods:A total of 60 eligible patients of chronic gastritis were randomized into two groups,a ST 36 group(ginger-isolated moxibustion at ST 36,30 cases)and a PC 6 group(ginger-isolated moxibustion at PC 6,30 cases).Before and after 6 treatments,the total variability of heart rate(TV)and the scores in Scale for gastrointestinal diseases of traditional Chinese medicine were determined and recorded.Using correlation analysis,the hidden correlation condition that affects the therapeutic outcomes was excavated from the data.With least square method,the gradient curve(K value)of TV in treatment was estimated and the correlation between the effect mechanism and autonomic nerve regulation was excavated.Results:①In ST 36 group,the duration of sickness,severity of disease and the activity of autonomic nerve before treatment presented the underlying correlation with the therapeutic effects.In contrast,the hidden correlation in PC 6 group was not clear.②In ST 36 group,the higher K value of TV in treatment was,the more significant the therapeutic effects were,but in PC group,K value was reversely related to the therapeutic effects.Conclusion:The therapeutic effects of ginger-isolated moxibustion at single acupoint are correlated with the duration and severity of sickness.The therapeutic effects in ST 36 group were improved by the modulation of autonomic nerve activity and the effects in PC 6 group were negatively correlated with autonomic nerve activity.It is deduced that the effect mechanisms are different on single acupoint for chronic gastritis between the two points. 展开更多
关键词 ISOLATED GINGER MOXIBUSTION Chronic GASTRITIS Data mining Association algorithm
Pathogenic Characterization and Full Length Genome Sequence of a Reassortant Infectious Bursal Disease Virus Newly Isolated in Pakistan
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作者 Altaf Hussain Tiantian Wu +15 位作者 Hui Li Linjin Fan Kai Li Li Gao Yongqiang Wang Yulong Gao Changjun Liu Hongyu Cui Qing Pan Yanping Zhang Asim Aslam Khan Muti-Ur-Rehman Muhammad Munir Salman Latif Butt Xiaomei Wang Xiaole Qi 《中国病毒学:英文版》 CAS CSCD 2019年第1期102-105,共4页
Dear Editor,Infectious bursal disease (IBD) is one of the most important diseases of the poultry. The IBD virus (IBDV), a nonenveloped virus belonging to the Birnaviridae family with a genome consisting of two segment... Dear Editor,Infectious bursal disease (IBD) is one of the most important diseases of the poultry. The IBD virus (IBDV), a nonenveloped virus belonging to the Birnaviridae family with a genome consisting of two segments of double-stranded RNA (segments A and B), targets B lymphocytes of bursa of Fabricious leading to immunosuppression. In Pakistan,poultry farming is the second biggest industry and IBD is the second biggest disease threating the poultry sector.However. 展开更多
关键词 In PATHOGENIC CHARACTERIZATION and Full LENGTH Genome Sequence of a REASSORTANT Infectious Bursal Disease Virus NEWLY ISOLATED in Pakistan
一个FBN1基因突变的先天性单纯性晶状体异位家系的分析 预览
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作者 叶晔 刘欣华 +2 位作者 孙良南 蔡嘉敏 赵军 《中华眼科医学杂志(电子版)》 2019年第5期292-297,共6页
目的分析一个晶状体异位家系的临床特征及致病基因,并探讨基因突变与其临床表型间的关系。方法2018年8月收集晶状体异位家系的临床资料,绘制家系系谱图。采集家系成员的外周静脉血,提取基因组脱氧核糖核酸,应用靶向基因测序方法初步筛... 目的分析一个晶状体异位家系的临床特征及致病基因,并探讨基因突变与其临床表型间的关系。方法2018年8月收集晶状体异位家系的临床资料,绘制家系系谱图。采集家系成员的外周静脉血,提取基因组脱氧核糖核酸,应用靶向基因测序方法初步筛选该家系候选突变基因,采用Sanger测序验证和家系共分离分析,确定该家系的致病基因及其突变位点。结果该家系成员共有两代4人。其中,先证者Ⅱ1及其患病母亲分别于6岁及17岁时确诊为双眼晶状体异位,无骨骼系统及心血管系统等异常;先证者Ⅱ1及其患病母亲携带FBN1基因c.1600T>A(p.C534S)杂合突变,生物信息学分析提示具有高致病性,符合家系共分离特征。结论该家系符合先天性单纯性晶状体异位疾病特征;FBN1基因c.1600T>A(p.C534S)是该家系的致病突变,为常染色体显性遗传;该位点突变导致第534号氨基酸由半胱氨酸变异为丝氨酸,此为人群中的首次报道。 展开更多
关键词 先天性 单纯性 晶状体异位 FBN1基因 家系
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Carrier Envelope Phase Description for an Isolated Attosecond Pulse by Momentum Vortices
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作者 李猛 张贵志 +1 位作者 丁欣 姚键铨 《中国物理快报:英文版》 SCIE CAS CSCD 2019年第6期24-28,共5页
As a crucial parameter for a few-cycle laser pulse, the carrier envelope phase(CEP) substantially determines the laser waveform. We propose a method to directly describe the CEP of an isolated attosecond pulse(IAP) by... As a crucial parameter for a few-cycle laser pulse, the carrier envelope phase(CEP) substantially determines the laser waveform. We propose a method to directly describe the CEP of an isolated attosecond pulse(IAP) by the vortex-shaped momentum pattern, which is generated from the tunneling ionization of a hydrogen atom by a pair of time-delayed, oppositely and circularly polarized IAP-IR pulses. Superior to the angular streaking method that characterizes the CEP in terms of only one streak, our method describes the CEP of an IAP by the features of multiple streaks in the vortex pattern. The proposed method may open the possibility of capturing sub-cycle extreme ultraviolet dynamics. 展开更多
关键词 ISOLATED ATTOSECOND Pulse MOMENTUM VORTICES CARRIER ENVELOPE phase(CEP)
Effect of Bushen Hemai decoction on vascular stiffness in elderly patients with isolated systolic hypertension
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作者 Chun-Zhi Yue 《海南医科大学学报(英文版)》 2019年第3期36-39,共4页
Objective: To investigate the effect of Bushen Hemai decoction on the wall stiffness of middle-aged and elderly patients with simple systolic hypertension. Methods: The 126 middle-aged and elderly patients with simple... Objective: To investigate the effect of Bushen Hemai decoction on the wall stiffness of middle-aged and elderly patients with simple systolic hypertension. Methods: The 126 middle-aged and elderly patients with simple systolic hypertension admitted to our hospital from May 2010 to May 2015 were randomly divided into control group (63 cases) and observation group (63 cases). The control group was treated with conventional Western medicine, while the observation group was treated with Bushen Hemai decoction on the basis of the control group. The two groups were treated for 4 weeks. Results: The systolic blood pressure of the two groups decreased after treatment (observation group: T=16.165, control group: T=13.537, P<0.05);the systolic blood pressure of the two groups did not change significantly after treatment (observation group: T=1.857, control group: T=0.483, P>0.05);the systolic blood pressure of the observation group was lower than that of the control group after treatment (T=16.165, P<0.05). After treatment, the level of ST segment of ECG in the two groups was lower than that before treatment (observation group: T=22.145, control group: T=11.007, P<0.05);after treatment, the level of ST segment of ECG in the observation group was lower than that in the control group (T=8.130, P<0.05). After treatment, the pulse conduction velocity of the two groups was lower than that of the control group (observation group:T=8.694, control group: T=3.944, P<0.05);after treatment, the pulse conduction velocity of the observation group was lower than that of the control group (T=5.326, P<0.05). The total effective rate of the observation group (93.65%) was higher than that of the control group (76.19%) (P<0.05). Conclusion: Bushen Hemai Decoction has a significant clinical effect on middle-aged and elderly patients with simple systolic hypertension, and can improve the stiffness of the tube wall, which is worthy of clinical reference. 展开更多
关键词 Bushen Hemai DECOCTION Isolated SYSTOLIC HYPERTENSION in MIDDLE and OLD age Wall STIFFNESS
绿萝内生真菌中甲醛降解菌的筛选和鉴定 预览
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作者 廉佳佩 段乔健 +4 位作者 张云 焦乐乐 李晓军 延文星 张弘弛 《山东化工》 CAS 2019年第7期232-234,共3页
目的从市面销售的普通绿萝中筛选出一种对于甲醛有降解特性的真菌,并对于其生长曲线以及对甲醛的降解特性作进一步的研究。方法以甲醛为唯一碳源分离纯化可降解甲醛的真菌并使用察氏培养基培养以分析该真菌的形态特征并对于其分子生物... 目的从市面销售的普通绿萝中筛选出一种对于甲醛有降解特性的真菌,并对于其生长曲线以及对甲醛的降解特性作进一步的研究。方法以甲醛为唯一碳源分离纯化可降解甲醛的真菌并使用察氏培养基培养以分析该真菌的形态特征并对于其分子生物学特征进行鉴定。用称量菌丝干重的方法测定生长曲线,同时用乙酰丙酮测定此真菌对于甲醛的降解率。结果从绿萝中筛选出一种对于甲醛有降解性能的真菌Ea-01,经过鉴定其属于青霉菌属。 展开更多
关键词 内生真菌 甲醛降解菌 筛选 降解特性
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Testosterone undecanoate supplementation together with human chorionic gonadotropin does not impair spermatogenesis in males with isolated hypogonadotropic hypogonadism:a retrospective study
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作者 Yin-Wei Chen Yong-Hua Niu +6 位作者 Hao Xu Dao-Qi Wang Hong-Yang Jiang Gaurab Pokhrel Tao Wang Shao-Gang Wang Ji-Hong Liu 《亚洲男性学杂志:英文版》 SCIE CAS CSCD 2019年第4期413-418,共6页
Gon adotropin therapy is comm only used to in duce virilizati on and spermatoge nesis in male isolated hypog on adotropic hypog on adism (IHH) patients. In clinical practice, 5.6%-15.0% of male IHH patients show poor ... Gon adotropin therapy is comm only used to in duce virilizati on and spermatoge nesis in male isolated hypog on adotropic hypog on adism (IHH) patients. In clinical practice, 5.6%-15.0% of male IHH patients show poor responses to gonadotropin treatment;therefore, testosterone (T) suppleme ntation can serve as an alter native therapy to no rmalize serum T levels and promote virilization. However, treatment with exogenous T impairs spermatogenesis and suppresses intratesticular T levels. This retrospective study aimed to determine whether oral testosterone undeca noate (TU) suppleme ntation together with human chorionic gonadotropin (hCG) would negatively affect spermatogenesis in IHH patients compared with hCG alone. One hundred and seven IHH patients were included in our study. Fifty-four patients received intramuscular hCG and oral TU, and 53 patients received intramuscular hCG alone. The median follow-up time was 29 (range: 12-72) mon ths in both groups. Compared with the hCG group, the hCG/TU group required a shorter median time to normalize serum T levels (P < 0.001) and achieve Tanner stage (III and V) of pubic hair and genital development (P < 0.05). However, there were no significant differences in the rate of seminal spermatozoa appearance, sperm concentration, or median time to achieve different sperm concentration thresholds between the groups. In addition, there were no significant differences in side effects, such as acne and gynecomastia, observed in both groups. This study indicates that oral TU supplementation together with hCG does not impair spermatogenesis in treated IHH patients compared with hCG alone, and it shortens the time to normalize serum T levels and promote virilization. 展开更多
关键词 human chorionic GONADOTROPIN ISOLATED hypogonadotropic HYPOGONADISM SPERMATOGENESIS TESTOSTERONE undecanoate virilization
Quaternary antiferromagnetic Ba2BiFeS5 with isolated FeS4 tetrahedra
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作者 王少华 张晓 雷和畅 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第8期329-332,共4页
We report the detailed physical properties of quaternary compound Ba2BiFeS5 with the key structural ingredient of isolated FeS4 tetrahedra.Magnetization and heat capacity measurements clearly indicate that Ba2BiFeS5 h... We report the detailed physical properties of quaternary compound Ba2BiFeS5 with the key structural ingredient of isolated FeS4 tetrahedra.Magnetization and heat capacity measurements clearly indicate that Ba2BiFeS5 has a paramagnetic to antiferromagnetic transition at about 30 K.The calculated magnetic entropy above ordering temperature is much smaller than theoretical value for high-spin Fe^3+ion with S=5/2,implying the possible short-range antiferromagnetic fluctuation in Ba2BiFeS5. 展开更多
关键词 ISOLATED FeS4 TETRAHEDRA ANTIFERROMAGNETIC transition SHORT-RANGE ANTIFERROMAGNETIC FLUCTUATION
超声造影在诊断肿块型自身免疫性胰腺炎中的临床价值 被引量:1
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作者 张琪 杨道辉 +4 位作者 于凌云 董怡 曹佳颖 毛枫 王文平 《中国超声医学杂志》 CSCD 北大核心 2019年第1期35-38,共4页
目的探讨超声造影(CEUS)在肿块型自身免疫性胰腺炎(AIP)术前诊断及鉴别诊断中的价值。方法回顾性对比分析19例肿块型AIP与20例胰腺导管腺癌(PDAC)的CEUS表现。结果所有肿块型AIP病灶在动脉期均表现为整体高增强(n=12,63.16%)或等增强(n=... 目的探讨超声造影(CEUS)在肿块型自身免疫性胰腺炎(AIP)术前诊断及鉴别诊断中的价值。方法回顾性对比分析19例肿块型AIP与20例胰腺导管腺癌(PDAC)的CEUS表现。结果所有肿块型AIP病灶在动脉期均表现为整体高增强(n=12,63.16%)或等增强(n=7,36.84%),在延迟期呈高增强(n=8,42.11%)或等增强(n=11,57.89%)。而95.00%(n=19)的PDAC病灶在动脉期静脉期及延迟期均呈低增强(P<0.05)。结论超声造影凭借其无创、简便、可多次反复检查等优势,有助于术前诊断及鉴别诊断肿块型AIP,在临床实践中有潜在的应用价值。 展开更多
关键词 超声造影 自身免疫性胰腺炎 肿块型 胰腺导管腺癌 鉴别诊断
病因不明的孤立性眩晕患者与颅内动脉形态和脑灌注的相关性
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作者 程飞 周世玲 杨辉 《中国临床研究》 CAS 2019年第4期489-492,共4页
目的探讨病因不明的孤立性眩晕(UIV)患者与颅内动脉形态、脑灌注情况的相关性,以期为UIV的诊治提供参考。方法选取2015年1月至2018年5月反复发作的眩晕患者80例,其中UIV组47例,良性发作性位置性眩晕(BPPV)组33例,入院2 d内进行头颅CT检... 目的探讨病因不明的孤立性眩晕(UIV)患者与颅内动脉形态、脑灌注情况的相关性,以期为UIV的诊治提供参考。方法选取2015年1月至2018年5月反复发作的眩晕患者80例,其中UIV组47例,良性发作性位置性眩晕(BPPV)组33例,入院2 d内进行头颅CT检查,另选取同期进行头颅CT检查的健康体检者40例作为对照组。分析不同颅内动脉形态、脑灌注情况与UIV的关系,并对影响UIV的危险因素进行非条件Logistic回归分析。结果 UIV组、BPPV组高血压、血脂异常、糖尿病发生率高于对照组(P<0.05,P<0.01),UIV组高血压、血脂异常发生率高于BPPV组(P均<0.05);UIV组和BPPV组椎动脉(VA)狭窄、VA闭塞、VA优势型或VA发育不良(VAD或VAH)、基底动脉(BA)狭窄、BA发育不良(BAH)、BA弯曲(BAC)发生率分别高于对照组(P<0.05,P<0.01),且UIV组VA狭窄、VA闭塞、VAD/VAH及BAC发生率均高于BPPV组(P<0.05,P<0.01);UIV组、BPPV组相对脑血流量(rCBF)降低、相对脑血容量(rCBV)降低、平均通过时间(MTT)延迟、达峰时间(TTP)延迟发生率分别均高于对照组(P<0.05,P<0.01),UIV组rCBF降低、rCBV降低发生率高于BPPV组(P<0.05)。非条件Logistic回归分析显示,高血压、血脂异常、VAD或VAH、rCBF降低、rCBV降低是UIV发生的独立危险因素(P<0.05,P<0.01)。结论在合并血管危险因素的基础上,颅内后循环基底椎动脉形态异常引起的小脑和脑干低灌注与UIV的发生具有相关性。 展开更多
关键词 眩晕 孤立性 病因不明 颅内动脉 后循环 脑灌注 危险因素
败酱草化学成分研究 预览
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作者 刘洋成 刘伟 +2 位作者 陈刚 项峥 陈长兰 《哈尔滨商业大学学报:自然科学版》 CAS 2019年第2期138-140,170共4页
研究白花败酱草的化学成分,以95%乙醇溶液提取白花败酱草,依次采用石油醚、二氯甲烷、正丁醇对提取物进行萃取.正丁醇提取物分别采用硅胶柱色谱、ODS柱色谱以及葡聚糖凝胶色谱等技术进行分离,然后应用半制备型高效液相色谱进行纯化,共得... 研究白花败酱草的化学成分,以95%乙醇溶液提取白花败酱草,依次采用石油醚、二氯甲烷、正丁醇对提取物进行萃取.正丁醇提取物分别采用硅胶柱色谱、ODS柱色谱以及葡聚糖凝胶色谱等技术进行分离,然后应用半制备型高效液相色谱进行纯化,共得到7个化合物.通过核磁共振技术,结合相关文献对比后确定全部化合物结构.分别为Caffeic acid ethyl ester (1),Caffeic acid n-butyl ester (2),Apigenin (3),Luteolin (4),Menthalignin (5),Methyl 2-(4-hydroxyphenyl) acetate (6),trans -Ferulic acid (7).其中化合物1~3,6,7均为首次从该植物中分离得到. 展开更多
关键词 白花败酱草 化学成分 纯化 分离 结构鉴定
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Low Pathogenic Avian Influenza A(H5N7) Virus Isolated from a Domestic Duck in Dongting Lake Wetland of China,2016
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作者 Liping Ma Haizhou Liu +4 位作者 Runkun Wang Tao Jin Di Liu George Fu Gao Quanjiao Chen 《中国病毒学:英文版》 CAS CSCD 2019年第1期97-101,共5页
Dear Editor,The avian influenza virus (AIV) H5N7 was first isolated from wild birds in North America in 2001 (Spackman et al.2007), and information on only 25 strains of this virus has been deposited in the Global Ini... Dear Editor,The avian influenza virus (AIV) H5N7 was first isolated from wild birds in North America in 2001 (Spackman et al.2007), and information on only 25 strains of this virus has been deposited in the Global Initiative on Sharing All Influenza Data (GISAID-http://platform.gisaid.org/epi3/frontend#493de3) database until October 30, 2018. Twenty viruses were identified in the United States from 2001 to2017. 展开更多
关键词 HPAIV VIRUS ISOLATED from a Domestic DUCK in Dongting Lake Wetland of China 2016 Low PATHOGENIC AVIAN Influenza A
单纯性完全性肺静脉异位引流的产前超声诊断 预览
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作者 杨荣萍 贺山鹰 冯雪涛 《重庆医学》 CAS 2019年第17期2979-2982,共4页
目的探讨产前超声心动图对单纯性完全性肺静脉异位引流(ITAPVC)的诊断价值及漏诊原因。方法选取2009年1月至2017年6月隆昌市人民医院产前超声诊断并经产后超声心动图(或引产后尸检)证实为ITAPVC的胎儿18例,回顾性分析其产前超声筛查资料... 目的探讨产前超声心动图对单纯性完全性肺静脉异位引流(ITAPVC)的诊断价值及漏诊原因。方法选取2009年1月至2017年6月隆昌市人民医院产前超声诊断并经产后超声心动图(或引产后尸检)证实为ITAPVC的胎儿18例,回顾性分析其产前超声筛查资料,总结二维超声及彩色多普勒血流成像(CDFI)特征,并随访临床结果。结果18例ITAPVC中,心上型13例,心内型2例,心下型3例。13例不伴肺静脉回流梗阻,其中11例经产前超声筛出(7例于中期筛查时检出,4例于晚期筛查时检出),另2例产前漏诊,产后超声确诊;11例均经优生咨询,选择继续妊娠,于产后及时手术干预,均疗效满意。5例伴肺静脉回流梗阻,其中4例于产前筛查检出[3例梗阻均位于垂直静脉(VV)汇入左无名静脉处,1例位于VV穿膈肌处],选择终止妊娠,并经尸解确诊;另1例产前漏诊,继续妊娠,产后即出现难以控制的发绀、呼吸困难,并于出生后2 h即死亡,经尸检证实为心下型,伴VV穿膈肌处狭窄。结论肺静脉入口的观察是ITAPVC产前诊断及减少漏诊的关键,肺静脉回流梗阻有无的判断是该病诊断的重要内容。 展开更多
关键词 完全性肺静脉异位引流 单纯性 超声心动图描记术 产前诊断
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矩阵式隔离型双向AC-DC变换器控制策略 预览
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作者 梅杨 黄伟超 刘子毓 《电工技术学报》 EI CSCD 北大核心 2019年第12期2499-2506,共8页
针对矩阵式隔离型双向AC-DC变换器,提出一种控制策略,即前级矩阵变换电路和后级全桥电路的调制策略以及矩阵变换器双向开关的换流方法。其中,前级矩阵变换电路的调制基于双线电压调制思路,对扇区进行重新划分,调整和优化开关状态选择,... 针对矩阵式隔离型双向AC-DC变换器,提出一种控制策略,即前级矩阵变换电路和后级全桥电路的调制策略以及矩阵变换器双向开关的换流方法。其中,前级矩阵变换电路的调制基于双线电压调制思路,对扇区进行重新划分,调整和优化开关状态选择,以满足简化换流需求,后级全桥电路根据前级矩阵变换电路的调制策略,配合前级调节脉冲宽度进行协调控制,双向开关换流采用基于交流电压相对大小的两步换流方法。仿真和实验结果表明,在整流和逆变模式下,矩阵式隔离型双向AC-DC变换器均能保证网侧电流正弦,功率因数接近于1,输出电压电流可以保持恒定。由此证明,提出的控制策略,可实现变换器能量双向变换,且输入输出性能优良。 展开更多
关键词 AC-DC变换器 矩阵变换器 控制策略 隔离型
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The genetic diversity,individual relatedness and possible mating system of an isolated population of the Cyprinid species Megalobrama pellgrini in upper reaches of the Changjiang(Yangtze)River,China 预览
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作者 WANG Huanshan WANG Teng +1 位作者 LI Wenjing LIU Huanzhang 《海洋湖沼学报(英文)》 SCIE CAS CSCD 2019年第3期1042-1050,共9页
Megalobrama pellegrini is a cyprinid fish endemic to upper reaches of the Changjiang(Yangtze)River,China,which is also an important economic species in the local area.In recent years,resources of this species have dec... Megalobrama pellegrini is a cyprinid fish endemic to upper reaches of the Changjiang(Yangtze)River,China,which is also an important economic species in the local area.In recent years,resources of this species have decreased sharply and its conservation has drawn great attention.In the present study,we collected 120 individuals from the Longxi River,a tributary isolated from the main channel of the Changjiang River,where M.pellegrini is still relatively abundant.Using two different molecular markers,mitochondrial cytochrome b(cyt b)gene,and nuclear microsatellite(simple sequence repeat,SSR),we analyzed the genetic diversity of this isolated population.The results show that sequence genetic diversity was low(Hd:0.290 and P i:0.000 77 for cyt b gene),while the SSR genetic diversity was high(Ho:0.824 4±0.147 2,He:0.823 5±0.145 1).Analysis indicated that this population had experienced a bottleneck,with inbreeding and small effective population size(around 50).Based on SSR data,relatedness analyzing revealed that the 120 samples were grouped into 10 completely independent clusters.It was inferred that the mating system of M.pellegrini was polygamy.We suggested that the low genetic diversity could be induced by the overfishing and inbreeding depression.Therefore,we suggested that the urgent conservation measures should be taken to control the overfi shing and give better conditions for the fish to grow and spawn,then to restore population size. 展开更多
关键词 isolated population genetic diversity INDIVIDUAL relatedness MATING system conservation
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