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慢性束缚应激诱导脂肪Nox-4表达及其在脂肪炎症发生中的作用
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作者 买买提·依斯热依力 买买提艾力·艾则孜 +8 位作者 吾布力卡斯木·吾拉木 艾克拜尔·艾力 李义亮 阿孜古丽·阿力木江 赵新胜 闫晶 沙迪古丽·吾甫尔 蒋媛 克力木·阿不都热依木 《中华内分泌代谢杂志》 CAS CSCD 北大核心 2019年第5期410-416,共7页
目的探讨慢性束缚应激诱导脂肪组织NADPH氧化酶4(Nox-4)表达及其在脂肪炎症发生中的作用。方法雄性SPF级20只昆明小鼠随机分2组(每组10只),即束缚应激组和正常对照组。束缚应激小鼠每天在自制式束缚器中限制活动2h,持续14天。采用HE染... 目的探讨慢性束缚应激诱导脂肪组织NADPH氧化酶4(Nox-4)表达及其在脂肪炎症发生中的作用。方法雄性SPF级20只昆明小鼠随机分2组(每组10只),即束缚应激组和正常对照组。束缚应激小鼠每天在自制式束缚器中限制活动2h,持续14天。采用HE染色、免疫组化、RT-PCR及ELISA等试验方法检测脂肪组织和血液中Nox-4,巨噬细胞表面标志物(CD11b、CD68、F4/80),抗氧化蛋白(Mn-SOD、GSH-Px、Catalase),脂肪细胞因子(脂联素、MCP-1、IL-6、TNF-α)等指标的表达。结果应激小鼠腹股沟脂肪垫白色脂肪组织(WAT)与对照组相比显著缩小。应激组WAT出现大量的单核细胞、中性粒细胞浸润反应和炎症性改变。应激组WAT组织中CD11b阳性细胞的比例及F4/80、CD68的mRNA表达水平显著升高。应激组FFA释放的浓度显著增高,约对照组的2倍(P<0.01)。Nox-4主要表达于脂肪细胞中,应激组Nox-4的mRNA表达和血清浓度显著高于对照组(P<0.01);应激组WAT组织中脂联素的mRNA表达与对照组相比显著降低(P<0.01);应激组WAT组织中MCP-1、IL-6及TNF-α的mRNA表达与对照组相比显著增高(P<0.01)。结论心理应激导致脂肪氧化、抗氧化系统破坏,使得脂肪细胞因子表达异常,进而引起脂肪组织炎症。 展开更多
关键词 慢性束缚应激 氧化应激 脂肪细胞因子 脂肪炎症
Coulomb stress evolution along the Kongur Extensional System since 1895 and present seismic hazard
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作者 Wei Xiong Xuejun Qiao +2 位作者 Gang Liu Wei Chen Zhaosheng Nie 《大地测量与地球动力学:英文版》 2019年第1期1-9,共9页
The present-day tectonic activities on the northeastern margin of the Pamir Plateau are mainly E-W oriented extensions,among which the Kongur Extensional System(KES)plays an important role in the internal expansion of... The present-day tectonic activities on the northeastern margin of the Pamir Plateau are mainly E-W oriented extensions,among which the Kongur Extensional System(KES)plays an important role in the internal expansion of the Pamir.As the largest earthquake since Taxkorgan earthquakes in 1895 and 1896,the Aketao earthquake occurred on the Muji fault on the northern portion of the KES in 2016.Since then,the trend of seismic activities along the KES has been paid much attention to.Based on the visco elastic layered lithosphere model,we calculate the co-seismic and post-seismic stress changes caused by five historical earthquakes on the KES and its adjacent areas since 1895,and analyze the interaction among strong earthquakes.The results show that all of the historical earthquakes after 1895 occurred in the areas where the co-seismic and post-seismic Coulomb stress increased.Coulomb stress loading at the hypocenters of the 1896 Taxkorgan earthquake,the 1974 Markansu earthquake and the 2016 Aketao earthquake were 0.251 MPa,0.013 MPa and 0.563 MPa,respectively.The three earthquakes were catalyzed by such variations.The historical earthquakes increased the stress state on most segments of the Southern Kungai Mountain fault and Kongur fault along the KES.In particular,we can identify 2 visible earthquake gaps with increasing seismic hazard formed on the Qimugan segment and Bulunkou segment of the KES.The Qimugan section and the Bulunkou section are located at the fault transition zone with concentrated stress and high extension rate,so great attention should be paid to their seismic hazard at present day. 展开更多
关键词 Kongur EXTENSIONAL SYSTEM COULOMB STRESS STRESS accumulation Seismic HAZARD
Resveratrol reduces brain injury after subarachnoid hemorrhage by inhibiting oxidative stress and endoplasmic reticulum stress 预览
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作者 Yun-Kai Xie Xin Zhou +5 位作者 Hong-Tao Yuan Jie Qiu Dan-Qing Xin Xi-Li Chu Da-Chuan Wang Zhen Wang 《中国神经再生研究:英文版》 SCIE CAS CSCD 2019年第10期1734-1742,共9页
Previous studies have shown that resveratrol,a bioactive substance found in many plants,can reduce early brain injury after subarachnoid hemorrhage,but how it acts is still unclear.This study explored the mechanism us... Previous studies have shown that resveratrol,a bioactive substance found in many plants,can reduce early brain injury after subarachnoid hemorrhage,but how it acts is still unclear.This study explored the mechanism using the experimental subarachnoid hemorrhage rat model established by injecting autologous blood into the cerebellomedullary cistern.Rat models were treated with an intraperitoneal injection of 60 mg/kg resveratrol 2,6,24 and 46 hours after injury.At 48 hours after injury,their neurological function was assessed using a modified Garcia score.Brain edema was measured by the wet-dry method.Neuronal apoptosis in the prefrontal cortex was detected by terminal deoxyribonucleotidyl transferase-mediated biotin-16-dUTP nick-end labeling assay.Levels of reactive oxygen species and malondialdehyde in the prefrontal cortex were determined by colorimetry.CHOP,glucose-regulated protein 78,nuclear factor-erythroid2-related factor 2 and heme oxygenase-1 mRNA expression levels in the prefrontal cortex were measured by reverse transcription polymerase chain reaction.Tumor necrosis factor-alpha content in the prefrontal cortex was detected by enzyme linked immunosorbent assay.Immunohistochemical staining was used to detect the number of positive cells of nuclear factor-erythroid 2-related factor 2,heme oxygenase 1,glucose-regulated protein 78,CHOP and glial fibrillary acidic protein.Western blot assay was utilized to analyze the expression levels of nuclear factor-erythroid 2-related factor 2,heme oxygenase 1,glucose-regulated protein 78 and CHOP protein expression levels in the prefrontal cortex.The results showed that resveratrol treatment markedly alleviated neurological deficits and brain edema in experimental subarachnoid hemorrhage rats,and reduced neuronal apoptosis in the prefrontal cortex.Resveratrol reduced the levels of reactive oxygen species and malondialdehyde,and increased the expression of nuclear factor-erythroid 2-related factor 2,heme oxygenase-1 mRNA and protein in the prefrontal cortex.Resveratrol 展开更多
关键词 nerve REGENERATION RESVERATROL oxidative STRESS endoplasmic reticulum STRESS neuroinflammation SUBARACHNOID hemorrhage nuclear factor-erythroid 2-related FACTOR 2 heme oxygenase-1 glucose-regulated protein 78 neural REGENERATION
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Effect of dexmedetomidine against liver ischemia-reperfusion injury in rats by reducing endoplasmic reticulum stress
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作者 Quan-Sheng Wang Re-Ti Ai Fei-Fei Lu 《海南医科大学学报(英文版)》 2019年第5期10-13,共4页
Objective:To investigate the effect of dexmedetomidine against liver ischemia-reperfusion injury in rats by reducing endoplasmic reticulum stress.Methods: A total of 24 adult male Sprague-Dawley rats were randomly div... Objective:To investigate the effect of dexmedetomidine against liver ischemia-reperfusion injury in rats by reducing endoplasmic reticulum stress.Methods: A total of 24 adult male Sprague-Dawley rats were randomly divided into sham operation group (6 rats, Sham group), liver ischemia-reperfusion injury group (6 rats, I/R group), and liver ischemia-reperfusion injury +dexmedetomidine pretreatment group (6 rats, I/R +Dex pretreatment group) (25μg/kg intraperitoneally 30 min before ischemia), and liver ischemia-reperfusion injury +dexmedetomidine post-treatment group (6 rats, I/R +Dex post-treatment group) (25 μg/kg intraperitoneally 30 min after reperfusion). Hepatic ischemia-reperfusion injury model was performed by after clamping the hepatic hilum for 30 min and reperfusion for 6 h. Serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels were measured by automatic biochemical analyzer. Malondialdehyde (MDA) and superoxide dismutase (SOD) activity were detected by enzyme-linked immunosorbent assay (ELISA). The pathological changes of each group were observed by HE staining. The expression of endoplasmic reticulum stress (P-PERK, P-IRE1 , CHOP) were detected by Western blot.Results: Compared with the Sham group, the serum levels of ALT and AST were significantly higher in the I/R group, compared with the I/R group, the serum ALT and AST in I/R+Dex pretreatment group and the I/R+Dex post-treatment group were significantly reduced;Compared with the Sham group, MDA activity in the liver tissue of the I/R group was significantly increased, while the SOD activity was significantly decreased, and the pathological score of the liver tissue was significantly increased;Compared with the I/R group, MDA activity and liver histopathology scores in I/R+Dex pretreatment group and the I/R+Dex post-treatment group were decreased, while SOD activity increased;The expression of P-PERK, P-IRE1 , CHOP in the I/R group were significantly higher than that in the Sham group, while the expression of the above in 展开更多
关键词 DEXMEDETOMIDINE LIVER Endoplasmic reticulum STRESS ISCHEMIA-REPERFUSION OXIDATIVE STRESS
血糖控制优化方案在肝胆外科术后应激性高血糖病人中的应用 预览
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作者 郭伟 李小臣 +3 位作者 李慧 曹丽 李娜 仰曙芬 《安徽医药》 CAS 2019年第8期1566-1569,共4页
目的探讨血糖控制优化方案(BGCOP)在肝胆外科术后应激性高血糖(SHG)病人中的应用效果。方法采用简单化随机分组法将2015年1-12月山东大学齐鲁医院86名符合条件的肝胆外科病人分为试验组(43例)和对照组(43例)。试验组采取BGCOP控制血糖,... 目的探讨血糖控制优化方案(BGCOP)在肝胆外科术后应激性高血糖(SHG)病人中的应用效果。方法采用简单化随机分组法将2015年1-12月山东大学齐鲁医院86名符合条件的肝胆外科病人分为试验组(43例)和对照组(43例)。试验组采取BGCOP控制血糖,对照组采取常规胰岛素强化治疗方案(CIIT)控制血糖。比较术后两组病人的血糖控制效果、不良反应发生率和并发症发生率。结果两组病人的一般资料在年龄、体质指数(BMI)、急性生理与慢性健康评分(APACHE)等方面差异无统计学意义(P>0.05),对后续研究没有影响。试验组采取BGCOP方案后血糖控制到目标值的时间为(4.54±1.51) h,对照组采用CIIT方案后血糖控制到目标值的时间为(8.54±2.68) h,试验组采用BGCOP方案后血糖控制到目标值的时间明显低于对照组,高血糖指数(0.86±0.24)也明显低于对照组(1.97±0.94),差异有统计学意义(t=8.724,t=7.895,P<0.001);试验组病人50%葡萄糖救援、低血糖、严重低血糖发生率明显低于对照组,均差异有统计学意义(P<0.05);两组病人发生高渗性昏迷的比率差异无统计学意义(P>0.05);试验组病人发生肺部感染、腹部感染和切口感染的比率明显低于对照组病人,差异有统计学意义(P<0.05)。结论与CIIT相比,BGCOP方案能更有效地控制肝胆外科术后SHG病人的血糖水平。 展开更多
关键词 高血糖症 手术后并发症 消化系统外科手术/副作用 胰岛素输注系统 应激 生理学 胰岛素 应激性高血糖
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Proteomics of the mediodorsal thalamic nucleus of rats with stress-induced gastric ulcer 预览
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作者 Sheng-Nan Gong Jian-Ping Zhu +1 位作者 Ying-Jie Ma Dong-Qin Zhao 《世界胃肠病学杂志:英文版》 SCIE CAS 2019年第23期2911-2923,共13页
BACKGROUND Stress-induced gastric ulcer(SGU) is one of the most common visceral complications after trauma. Restraint water-immersion stress(RWIS) can cause serious gastrointestinal dysfunction and has been widely use... BACKGROUND Stress-induced gastric ulcer(SGU) is one of the most common visceral complications after trauma. Restraint water-immersion stress(RWIS) can cause serious gastrointestinal dysfunction and has been widely used to study the pathogenesis of SGU to identify medications that can cure the disease. The mediodorsal thalamic nucleus(MD) is the centre integrating visceral and physical activity and contributes to SGU induced by RWIS. Hence, the role of the MD during RWIS needs to be studied.AIM To screen for differentially expressed proteins in the MD of the RWIS rats to further elucidate molecular mechanisms of SGU.METHODS Male Wistar rats were selected randomly and divided into two groups, namely, a control group and an RWIS group. Gastric mucosal lesions of the sacrificed rats were measured using the erosion index and the proteomic profiles of the MD were generated through isobaric tags for relative and absolute quantitation(iTRAQ) coupled with two-dimensional liquid chromatography and tandem mass spectrometry. Additionally, iTRAQ results were verified by Western blot analysis.RESULTS A total of 2853 proteins were identified, and these included 65 dysregulated(31 upregulated and 34 downregulated) proteins(fold change ratio ≥ 1.2). Gene Ontology(GO) analysis showed that most of the upregulated proteins are primarily related to cell division, whereas most of the downregulated proteins are related to neuron morphogenesis and neurotransmitter regulation. Ingenuity Pathway Analysis revealed that the dysregulated proteins are mainly involved in the neurological disease signalling pathways. Furthermore, our results indicated that glycogen synthase kinase-3 beta might be related to the central mechanismthrough which RWIS gives rise to SGU.CONCLUSION Quantitative proteomic analysis elucidated the molecular targets associated with the production of SGU and provides insights into the role of the MD. The underlying molecular mechanisms need to be further dissected. 展开更多
关键词 Mediodorsal THALAMIC nucleus Proteome Restraint water-immersion STRESS Stress-induced gastric ulcer GLYCOGEN SYNTHASE kinase-3 beta
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考虑T应力的岩石压剪裂纹起裂机理
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作者 刘红岩 《岩土工程学报》 EI CAS CSCD 北大核心 2019年第7期1296-1302,共7页
传统断裂理论在研究岩石压剪裂纹起裂机理时,往往仅考虑裂纹尖端应力场Williams展开式中的r1/2奇异应力项,而忽略了非奇异应力项(T应力)的影响,造成理论预测值与试验结果不符。在对压剪应力下裂纹受力特征进行分析的基础上,将T应力引入... 传统断裂理论在研究岩石压剪裂纹起裂机理时,往往仅考虑裂纹尖端应力场Williams展开式中的r1/2奇异应力项,而忽略了非奇异应力项(T应力)的影响,造成理论预测值与试验结果不符。在对压剪应力下裂纹受力特征进行分析的基础上,将T应力引入传统断裂力学的最大周向应力准则,提出了考虑T应力的修正最大周向应力准则。同时考虑压剪应力下的裂纹应力传递特点,在上述准则中又引入裂纹面法向刚度及切向刚度等变形参数。最终建立了能够同时考虑岩石性质和裂纹几何参数(如裂纹倾角、长度等)、强度参数(裂纹面摩擦系数)及变形参数(裂纹面法向及切向刚度)的最大周向应力准则,更好地反映了岩石压剪裂纹起裂机理。算例表明由该方法计算得到的翼裂纹起裂角与试验结果吻合较好,同时通过参数敏感性分析发现裂纹尖端相对临界尺寸对翼裂纹起裂角的影响最大。 展开更多
关键词 T应力 岩石 压剪断裂 翼裂纹起裂角 最大周向应力准则 裂纹面法向及切向刚度
Methodology to Evaluate Fatigue Damage of High-Speed Train Welded Bogie Frames Based on On-Track Dynamic Stress Test Data
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作者 Guangxue Yang Meng Wang +1 位作者 Qiang Li Ran Ding 《中国机械工程学报:英文版》 SCIE EI CAS CSCD 2019年第3期181-188,共8页
The current method of estimating the fatigue life of railway structures is to calculating the equivalent stress amplitude based on the measured stress data. However, the random of the measured data is not considered. ... The current method of estimating the fatigue life of railway structures is to calculating the equivalent stress amplitude based on the measured stress data. However, the random of the measured data is not considered. In this paper, a new method was established to compute the equivalent stress amplitude to evaluate the fatigue damage based on the measurable randomness, since the equivalent stress is the key parameter for assessment of structure fatigue life and load derivation. The equivalent stress amplitude of a high-speed train welded bogie frame was found to obey normal distribution under uniform operation route that verified by on-track dynamic stress data, and the proposed model is, in effect, an improved version of the mathematical model used to calculate the equivalent stress amplitude. The data of a long-term, on-track dynamic stress test program was analyzed to find that the normal distribution parameters of equivalent stress amplitude values differ across different operation route. Thus, the fatigue damage of the high-speed train welded bogie frame can be evaluated by the proposed method if the running schedule of the train is known a priori. The results also showed that the equivalent stress amplitude of the region connected to the power system is more random than in other regions of the bogie frame. 展开更多
关键词 Fatigue damage evaluation Equivalent STRESS AMPLITUDE On-track dynamic STRESS test Welded BOGIE frame of high-speed train
Pathological significance of tRNA-derived small RNAs in neurological disorders 预览
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作者 Chuan Qin Pei-Pei Xu +7 位作者 Xin Zhang Chao Zhang Chang-Bin Liu De-Gang Yang Feng Gao Ming-Liang Yang Liang-Jie Du Jian-Jun Li 《中国神经再生研究:英文版》 SCIE CAS CSCD 2020年第2期212-221,共10页
Non-coding RNAs(ncRNAs) are a type of RNA that is not translated into proteins. Transfer RNAs(tRNAs), a type of ncRNA, are the second most abundant type of RNA in cells. Recent studies have shown that tRNAs can be cle... Non-coding RNAs(ncRNAs) are a type of RNA that is not translated into proteins. Transfer RNAs(tRNAs), a type of ncRNA, are the second most abundant type of RNA in cells. Recent studies have shown that tRNAs can be cleaved into a heterogeneous population of ncRNAs with lengths of 18–40 nucleotides, known as tRNA-derived small RNAs(tsRNAs). There are two main types of tsRNA, based on their length and the number of cleavage sites that they contain: tRNA-derived fragments and tRNA-derived stress-induced RNAs. These RNA species were first considered to be byproducts of tRNA random cleavage. However, mounting evidence has demonstrated their critical functional roles as regulatory factors in the pathophysiological processes of various diseases, including neurological diseases. However, the underlying mechanisms by which tsRNAs affect specific cellular processes are largely unknown. Therefore, this study comprehensively summarizes the following points:(1) The biogenetics of tsRNA, including their discovery, classification, formation, and the roles of key enzymes.(2) The main biological functions of tsRNA, including its miRNA-like roles in gene expression regulation, protein translation regulation, regulation of various cellular activities, immune mediation, and response to stress.(3) The potential mechanisms of pathophysiological changes in neurological diseases that are regulated by tsRNA, including neurodegeneration and neurotrauma.(4) The identification of the functional diversity of tsRNA may provide valuable information regarding the physiological and pathophysiological mechanisms of neurological disorders, thus providing a new reference for the clinical treatment of neurological diseases. Research into tsRNAs in neurological diseases also has the following challenges: potential function and mechanism studies, how to accurately quantify expression, and the exact relationship between tsRNA and miRNA. These challenges require future research efforts. 展开更多
关键词 EPIGENETICS molecular biology NEUROLOGICAL disorders review sequencing STRESS tRNA tRNA-derived FRAGMENTS tRNA-derived small RNAs tRNA-derived stress-induced RNA
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A chemo-mechanical model for fully-coupled lithiation reaction and stress generation in viscoplastic lithiated silicon
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作者 BUREBI YiMing JIA Zheng QU ShaoXing 《中国科学:技术科学英文版》 SCIE EI CAS CSCD 2019年第8期1365-1374,共10页
Development of stresses in silicon(Si) anodes of lithium-ion batteries is strongly affected by its mechanical properties. Recent experiments reveal that the mechanical behavior of lithiated silicon is viscoplastic, th... Development of stresses in silicon(Si) anodes of lithium-ion batteries is strongly affected by its mechanical properties. Recent experiments reveal that the mechanical behavior of lithiated silicon is viscoplastic, thereby indicating that lithiation-induced mechanical stresses are dependent on the lithiation reaction rate. Experimental evidence also accumulates that the rate of lithiation reaction is conversely affected by the magnitude of mechanical stresses. These experimental observations demonstrate that lithiation reaction and stress generation in silicon anodes are fully coupled. In this work, we formulate a chemo-mechanical model considering the two-way coupling between lithiation reaction and viscoplastic deformation in silicon nanoparticle anodes.Based on the model, the position of the lithiation interface, the interface velocity, and the lithiation-induced stresses can be solved simultaneously via numerical methods. The predicted interface velocity is in line with experimental measurements reported in the literature. We demonstrate that the lithiation-induced stress field depends on the lithiation reaction through two parameters:the migration velocity and the position of the lithiation interface. We identify a stress-mitigation mechanism in viscoplastic silicon anodes: the stress-regulated lithiation reaction at the interface serves as a "brake" to reduce the interface velocity and mitigate the lithiation-induced stresses, protecting the Si nanoparticle anode from being subjected to excessive mechanical stresses. 展开更多
关键词 LITHIUM-ION BATTERY lithiation-induced STRESS stress-regulated LITHIATION VISCOPLASTICITY
Effects of capture and captivity on plasma corticosterone and metabolite levels in breeding Eurasian Tree Sparrows 预览
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作者 Mo Li Weiwei Zhu +6 位作者 Yang Wang Yanfeng Sun Juyong Li Xuelu Liu Yuefeng Wu Xuebin Gao Dongming Li 《鸟类学研究:英文版》 CSCD 2019年第2期228-237,共10页
Background: Bringing free-living animals into captivity subjects them to the stress of both capture and captivity, leading to the alteration of normal physiological processes and behaviors through activation of the hy... Background: Bringing free-living animals into captivity subjects them to the stress of both capture and captivity, leading to the alteration of normal physiological processes and behaviors through activation of the hypothalamic– pituitary–adrenal axis. In free-living birds, although elevated plasma corticosterone (CORT) is an important adaptation regulating physiological and behavioral responses during the process of capture and captivity stress, little information is currently available on the effects of such stress on plasma metabolite levels. Methods: We examined the effects of immediate capture and 24-h captivity on body mass, body condition, plasma CORT, and metabolite levels including glucose (Glu), triglyceride (TG), total cholesterol (TC), uric acid (UA), in breeding Eurasian Tree Sparrows (Passer montanus). Results: CORT and Glu levels were increased significantly by the stress of capture, whereas TC and UA levels decreased. Body mass, body condition declined notably after 24 h in captivity, but CORT, Glu, and UA levels increased. Furthermore, male sparrows had lower TG levels after both capture and captivity than those of females. The relationships between plasma CORT and metabolite levels varied between sexes. Conclusions: Our results revealed that the metabolic status of Eurasian Tree Sparrows could be dramatically altered by capture and captivity. Monitoring the dynamic effects of both capture and captivity on plasma CORT, metabolite levels in a free-living bird contributes to a better understanding of the stress-induced pathways involved in sexdependent energy mobilization. 展开更多
关键词 CAPTURE STRESS CAPTIVITY STRESS CORTICOSTERONE Plasma metabolites FREE-LIVING birds
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Psychosocial Stress,the Unpredictability Schema,and Cardiovascular Disease in Women 预览
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作者 Tomás Cabeza de Baca,PhD Michelle A.Albert,MD,MPH 《心血管创新与应用》 2019年第B02期391-401,共11页
Depression/anxiety-related disorders and psychosocial stress have been implicated as cardiovascular disease(CVD)risk factors.Women are at considerable risk for affective disorders and report greater severity from psyc... Depression/anxiety-related disorders and psychosocial stress have been implicated as cardiovascular disease(CVD)risk factors.Women are at considerable risk for affective disorders and report greater severity from psychosocial stress,compared to men.Affective disorders and cardiovascular disease likely share underlying pathophysiological mechanisms that are potentiated among women–especially younger women.Environmental stressors that threaten the safety,security,and status of an individual are appraised by the brain,producing a cascade of evoked physiological and cognitive responses.In the short term,these processes overcome stressors,but come with long-term health implications.Chronic psychosocial stress leads to a dysregulation of the stress response systems that can lead to a heightened stress appraisal schema called the unpredictability schema,a construct that might arguably place women at heightened risk for CVD. 展开更多
关键词 cardiovascular disease psychological STRESS depression ANXIETY WOMEN UNPREDICTABILITY SCHEMA life history theory PSYCHOSOCIAL STRESS
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Stress sensitivity of tight reservoirs during pressure loading and unloading process 预览
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作者 CAO Nai LEI Gang 《石油勘探与开发:英文版》 2019年第1期138-144,共7页
Laboratory experiments were conducted on laboratory-made tight cores to investigate the stress-dependent permeability hysteresis of tight reservoirs during pressure loading and unloading process. Based on experiment r... Laboratory experiments were conducted on laboratory-made tight cores to investigate the stress-dependent permeability hysteresis of tight reservoirs during pressure loading and unloading process. Based on experiment results, and Hertz contact deformation principle, considering arrangement and deformation of rock particles, a quantitative stress dependent permeability hysteresis theoretical model for tight reservoirs was established to provide quantitative analysis for permeability loss. The model was validated by comparing model calculated results and experimental results. The research results show that during the early pressure-loading period, structural deformation and primary deformation worked together, rock permeability reduced dramatically with increasing effective stress. When the effective stress reached a certain value, the structural deformation became stable while the primary deformation continued;the permeability variation tended to be smooth and steady. In the pressure unloading process, the primary deformation recovered with the decreasing effective stress, while the structural deformation could not. The permeability thus could not fully recover, and the stress-dependent hysteresis was obvious. 展开更多
关键词 TIGHT RESERVOIR STRESS sensitivity HYSTERESIS PERMEABILITY STRESS sensitivity laboratory experiment THEORETICAL model
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Predator stress-induced depression is associated with inhibition of hippocampal neurogenesis in adult male mice 预览
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作者 Yan-Ping Wu Hua-Ying Gao +3 位作者 Shu-Hua Ouyang Hiroshi Kurihara Rong-Rong He Yi-Fang Li 《中国神经再生研究:英文版》 SCIE CAS CSCD 2019年第2期298-305,共8页
Stress has been suggested to disturb the 5-hydroxytryptamine system and decrease neurogenesis, which contribute to the development of depression. Few studies have investigated the effect of predator stress, a type of ... Stress has been suggested to disturb the 5-hydroxytryptamine system and decrease neurogenesis, which contribute to the development of depression. Few studies have investigated the effect of predator stress, a type of psychological stress, on depression and hippocampal neurogenesis in adult mice; we therefore investigated this in the present study. A total of 35 adult male Kunming mice were allocated to a cat stress group, cat odor stress group, cat stress + fluoxetine group, cat odor stress + fluoxetine group, or a control group (no stress/treatment). After 12 days of cat stress or cat odor stress, behavioral correlates of depression were measured using the open field test, elevated plus maze test, and dark-avoidance test. The concentrations of hippocampal 5-hydroxytryptamine and 5-hydroxyindoleacetic acid were measured using high-performance liquid chromatography-electrochemical detection. Neurogenesis was also analyzed using a bromodeoxyuridine and doublecortin double-immunostaining method. Cat stress and cat odor stress induced depression-like behaviors; this effect was stronger in the cat stress model. Furthermore, compared with the control group, cat stress mice exhibited lower 5-hydroxytryptamine concentrations, higher 5-hydroxyindoleacetic acid concentrations, and significantly fewer bromodeoxyuridine+/doublecortin+-labeled cells in the dentate gyrus, which was indicative of less neurogenesis. The changes observed in the cat stress group were not seen in the cat stress + fluoxetine group, which suggests that the effects of predator stress on depression and neurogenesis were reversed by fluoxetine. Taken together, our results indicate that depression-like behaviors induced by predator stress are associated with the inhibition of hippocampal neurogenesis. 展开更多
关键词 nerve REGENERATION DEPRESSIVE disorder CAT STRESS CAT odor STRESS behavioral evaluation open field TEST elevated plus maze TEST dark-avoidance TEST 5-HYDROXYTRYPTAMINE 5-hydroxyindoleacetic acid hippocampal neurogenesis neural REGENERATION
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Simulation of ductile fracture initiation in steels using a stress triaxiality-shear stress coupled model 预览
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作者 Yazhi Zhu Michael D.Engelhardt Zuanfeng Pan 《力学学报:英文版》 SCIE EI CAS CSCD 2019年第3期600-614,共15页
Micromechanics-based models provide powerful tools to predict initiation of ductile fracture in steels. A new criterion is presented herein to study the process of ductile fracture when the effects of both stress tria... Micromechanics-based models provide powerful tools to predict initiation of ductile fracture in steels. A new criterion is presented herein to study the process of ductile fracture when the effects of both stress triaxiality and shear stress on void growth and coalescence are considered. Finite-element analyses of two different kinds of steel, viz. ASTM A992 and AISI 1045, were carried out to monitor the history of stress and strain states and study the methodology for determining fracture initiation. Both the new model and void growth model (VGM) were calibrated for both kinds of steel and their accuracy for predicting fracture initiation evaluated. The results indicated that both models offer good accuracy for predicting fracture of A992 steel. However, use of the VGM leads to a significant deviation for 1045 steel, while the new model presents good performance for predicting fracture over a wide range of stress triaxiality while capturing the effect of shear stress on fracture initiation. 展开更多
关键词 DUCTILE fracture VOID growth STRESS TRIAXIALITY Shear STRESS ratio ASTM A992 STEEL AISI 1045 STEEL
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CRISPR/Cas9:Development and Application in Rice Breeding 预览
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作者 Fernando Matias ROMERO Andres GATICA-ARIAS 《水稻科学:英文版》 CSCD 2019年第5期265-281,共17页
Rice(Oryza sativa L.)is an important staple food crop worldwide due to its adaptability to different environmental conditions.Because of its great economic and social importance,there is a constant requirement for new... Rice(Oryza sativa L.)is an important staple food crop worldwide due to its adaptability to different environmental conditions.Because of its great economic and social importance,there is a constant requirement for new varieties with improved agronomic characteristics,such as tolerance to different biotic(such as bacterium,fungus,insect and virus)and abiotic stresses(such as salinity,drought and temperature),higher yield and better organoleptic and nutritional value.Among the new genome editing technologies,the clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR-associated protein(Cas)(CRISPR/Cas)system allows precise and specific edition in a targeted genome region.It is one of the most frequently used techniques for the study of the function of new genes and for the development of mutant lines with enhanced tolerance to biotic and abiotic stresses,herbicide resistance or improved yield.The wide varieties of applications for this technology include simple non-homologous end joining,homologous recombination,gene replacement,and base editing.In this review,we analyzed how some of these applications have been used in rice cultivars to obtain rice varieties better adapted to current environmental conditions and market requirements. 展开更多
关键词 rice CRISPR Cas genome editing biotic stress abiotic stress YIELD off-target MUTATION
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Genome-wide identification and characterization of HSP gene superfamily in whitefly (Bemisia tabacl)and expression profiling analysis under temperature stress
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作者 Xin-Ru Wang Chao Wang +3 位作者 Fei-Xue Ban Dan-Tong Zhu Shu-Sheng Liu Xiao-Wei Wang 《昆虫科学:英文版》 SCIE CAS CSCD 2019年第1期44-57,共14页
Heat shock proteins (HSP)are essential molecular chaperones that play important roles in the stress stimulation of insects.Bemisia tabaci,a phloem feeder and invasive species,can cause extensive crop damage through di... Heat shock proteins (HSP)are essential molecular chaperones that play important roles in the stress stimulation of insects.Bemisia tabaci,a phloem feeder and invasive species,can cause extensive crop damage through direct feeding and transmission of plant viruses.Here we employed comprehensive genomics approaches to identity HSP superfamily members in the Middle East Asia Minor 1 whitefly genome.In total,we identified 26 Hsp genes,including three Hsp90,17 Hsp70,one Hsp60 and five sHSP (small heat shock protein)genes.The HSP gene superfamily of whitefly is expanded compared with the other five insects surveyed here.The gene structures among the same families are relatively conserved.Meanwhile,the motif compositions and secondary structures of BtHsp proteins were predicted.In addition,quantitative polymerase chain reaction analysis showed that the expression patterns of BtHsp gene superfamily were diverse across different tissues of whiteflies.Most Hsp genes were induced or repressed by thermal stress (40℃)and cold treatment (4℃)in whitefly.Silencing the expression of BtHsp70-6 significantly decreased the survival rate of whitefly under 45℃.All the results showed the Hsps conferred thermo-tolerance or cold-tolerance to whiteflies that protect them from being affected by detrimental temperature conditions.Our observations highlighted the molecular evolutionary properties and the response mechanism to temperature assaults of Hsp genes in whitefly. 展开更多
关键词 cold STRESS comparative genomics HSP PHYLOGENETIC thermal STRESS WHITEFLY
Hydrogen sulfide intervention in cystathionine-β-synthase mutant mouse helps restore ocular homeostasis
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作者 Akash K.George Rubens P.Homme +5 位作者 Avisek Majumder Anwesha Laha Naira Metreveli Harpal S.SANDhu Suresh C.Tyagi Mahavir Singh 《国际眼科杂志:英文版》 SCIE CAS 2019年第5期754-764,共11页
AIM: To investigate the applications of hydrogen sulfide(H2 S) in eye-specific ailments in mice.METHODS: Heterozygous cystathionine-β-synthase(CBS+/-) and wild-type C57 BL/6 J(WT) mice fed with or without high methio... AIM: To investigate the applications of hydrogen sulfide(H2 S) in eye-specific ailments in mice.METHODS: Heterozygous cystathionine-β-synthase(CBS+/-) and wild-type C57 BL/6 J(WT) mice fed with or without high methionine diet(HMD) were administered either phosphate buffered saline(PBS) or the slow-release H2 S donor: GYY4137. Several analyses were performed to study GYY4137 effects by examining retinal lysates for key protein expressions along with plasma glutamate and glutathione estimations. Intraocular pressure(IOP) was monitored during GYY4137 treatment;barium sulfate and bovine serum albumin conjugated fluorescein isothiocyanate(BSA-FITC) angiographies were performed for examining vasculature and its permeability post-treatment. Visionguided behavior was also tested employing novel object recognition test(NORT) and light-dark box test(LDBT) recordings.RESULTS: CBS deficiency(CBS+/-) coupled with HMD led disruption of methionine/homocysteine(Hcy) metabolism leading to hyperhomocysteinemia(HHcy) in CBS+/-mice as reflected by increased Hcy, and s-adenosylhomocysteine hydrolase(SAHH) levels. Unlike CBS, cystathionine-γ lyase(CSE), methylenetetrahydrofolate reductase(MTHFR) levels which were reduced but compensated by GYY4137intervention. Heightened oxidative and endoplasmic reticulum(ER) stress responses were mitigated by GYY4137 effects along with enhanced glutathione(GSH) levels. Increased glutamate levels in CBS+/-strain were prominent than WT mice and these mice also exhibited higher IOP that was lowered by GYY4137 treatment. CBS deficiency also resulted in vision-guided behavioral impairment as revealed by NORT and LDBT findings. Interestingly, GYY4137 was able to improve CBS+/-mice behavior together with lowering their glutamate levels. Blood-retinal barrier(BRB) appeared compromised in CBS+/-with vessels’ leakage that was mitigated in GYY4137 treated group. This corroborated the results for occludin(an integral plasma membrane protein of the cellular tight junctions) stabilization.CONCLUSION: Findings 展开更多
关键词 blood-retinal barrier integrity endoplasmic reticulum STRESS GLUTAMATE cytotoxicity inflammation oxidative STRESS mice
Icariin protects vascular endothelial cells from oxidative stress through inhibiting endoplasmic reticulum stress
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作者 Fang-yuan Wang Jian Jia +3 位作者 Huan-huan Song Cheng-ming Jia Chang-bo Chen Jing Ma 《结合医学学报:英文版》 CAS CSCD 2019年第3期205-212,共8页
Objective: To investigate the protective effect and underlying mechanism(s) of icariin(ICA) in preventing hydrogen peroxide(H2O2)-induced vascular endothelial cell injury via endoplasmic reticulum stress(ERS).Methods:... Objective: To investigate the protective effect and underlying mechanism(s) of icariin(ICA) in preventing hydrogen peroxide(H2O2)-induced vascular endothelial cell injury via endoplasmic reticulum stress(ERS).Methods: To study the effects of ICA on H2O2-induced damage, we used the cell counting kit-8 assay to detect cell viability and the terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling assay to determine cell adhesion and apoptosis, respectively. Spectrophotometry and enzyme-linked immunosorbent assay were used to measure the expression levels of superoxide dismutase(SOD) and glutathione peroxidase(GSH-Px). Subsequently, glucose-regulated protein 78(GRP78), activating transcription factor-4(ATF4) and eukaryotic initiation factor-2 a(eIF2 a) were detected using Western blotting.Results: In human umbilical vein endothelial cells, different concentrations of ICA exhibited multiple effects, including reduced H2O2 damage, improved cell viability and adhesion, reduced cell apoptosis and increased SOD and GSH-Px activity. Among the ICA concentrations used, only the H2O2+ 100 lmol/L ICA group had significant differences compared to the H2O2 group. ERS activators H2O2 and DL-dithiothreitol(DTT) significantly increased GRP78, ATF4 and eIF2 a expressions, decreased cell activity and reduced SOD and GSH-Px activity. In contrast, the H2O2+ 100 lmol/L ICA and H2O2+ 100 lmol/L ICA + DTT groups had significant inhibitory effects on the expressions of GRP78,ATF4 and eIF2 a proteins, showing enhanced cell viability and SOD and GSH-Px activity.Conclusion: The results showed the dose-dependent effects of ICA against H2O2-induced injury in vascular endothelial cells. The inhibition of GRP78, ATF4 and eIF2 a protein expressions in the ERS, and the subsequent alleviation of oxidative stress damage, might be the molecular mechanism. 展开更多
关键词 ICARIIN Endoplasmic reticulum STRESS Human UMBILICAL VEIN ENDOTHELIAL cells Oxidative STRESS
ESCRTing in cereals:still a long way to go
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作者 Verena Ibl 《中国科学:生命科学英文版》 SCIE CAS CSCD 2019年第9期1144-1152,共9页
The multivesicular body(MVB) sorting pathway provides a mechanism for the delivery of cargo destined for degradation to the vacuole or lysosome.The endosomal sorting complex required for transport(ESCRT) is essential ... The multivesicular body(MVB) sorting pathway provides a mechanism for the delivery of cargo destined for degradation to the vacuole or lysosome.The endosomal sorting complex required for transport(ESCRT) is essential for the MVB sorting pathway by driving the cargo sorting to its destination.Many efforts in plant research have identified the ESCRT machinery and functionally characterised the first plant ESCRT proteins.However,most studies have been performed in the model plant Arabidopsis thaliana that is genetically and physiologically different to crops.Cereal crops are important for animal feed and human nutrition and have further been utilized as promising candidates for recombinant protein production.In this review,I summarize the role of plant ESCRT components in cereals that are involved in efficient adaptation to environmental stress and grain development.A special focus is on barley(Hordeum vulgare L.) ESCRT proteins,where recent studies show their quantitative mapping during grain development,e.g.associating HvSNF7.1 with protein trafficking to protein bodies(PBs) in starchy endosperm.Thus,it is indispensable to identify the molecular key-players within the endomembrane system including ESCRT proteins to optimize and possibly enhance tolerance to environmental stress,grain yield and recombinant protein production in cereal grains. 展开更多
关键词 ESCRT CEREAL BARLEY grain ENDOSPERM SNF7 ABIOTIC STRESS biotic STRESS
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