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11.
大鼠放射性肺损伤模型的建立与动态观察   总被引:1,自引:0,他引:1  
孙万良  张晶  魏丽  章金刚  游华  张伟京 《生物磁学》2013,(26):5001-5007
目的:建立并鉴定大鼠放射性肺损伤模型,摸索大鼠放射性肺损伤的病理变化规律,阐明氧化应激在其发生发展过程中的作用。方法:采用60Co源22Gy单次照射SD大鼠全肺。分别于照射前、照后1天,7天,15天,21天,30天,60天,120天活杀大鼠,计算肺系数,右肺行HE染色、Masson染色及天狼猩红染色,观察肺组织病理变化并对大鼠肺泡炎及纤维化程度进行评分,免疫组化法检测肺组织廿SMA表达情况;左肺进行羟脯氨酸含量测定;血清测定MDA含量、总SOD活力和TGF-β1含量。结果:(1)大鼠肺脏于照后15天开始出现明显大体改变,病理学表现为间质性渗出性炎症并随时间延长逐渐加重,照后60天至120天肺脏塌陷,表面可见纤维化病灶,病理改变以肺间隔内细胞增生和胶原纤维沉积为主;(2)血清T-SOD活力照后1天至7天短暂增加后其活力持续降低;血清MDA含量和TGF-β1含量随时间时间延长逐渐增高;(3)照后60天肺组织a-SMA表达明显增加,至照后120天最为显著。结论:成功建立了大鼠放射性肺损伤模型并阐述了其病理变化规律;氧化应激参与了放射性肺损伤的病理过程。为其防治提供了实验基础和理论依据。  相似文献   
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Surveys were distributed to New Zealand land users in 1998 and 2008 to acquire information about New Zealand frogs with the aim of compiling and mapping their distribution and inferred population trends without costly and time-consuming field surveys. The overall frog population trend was reported as declining, with possible causes reported as an increase in agriculture, an increase in the distribution of predatory fish and disease. The resultant maps could be used for four main purposes: 1) to identify regions where Litoria populations are known to occur, which can be eliminated when considering suitable regions for translocation of Leiopelma; 2) to identify growing or stable populations of Litoria species, which may assist future disease surveys, population monitoring and to identify sources of genetic material that may serve as an Ark for declining Australian populations; 3) to highlight populations that are in decline to enable effective targeting of detailed disease studies; and 4) to approximate the stability of amphibian populations in the absence of more accurate, but costly, scientific monitoring.  相似文献   
14.
The importance of YWHAE gene polymorphisms (rs1532976, rs3752826, and rs9393) in the development of suicidal behavior has been studied in ethnic groups of Russians and Tatars from the Republic of Bashkortostan. It was revealed that the carriers of the YWHAE*C allele of rs3752826 polymorphism of the YWHAE gene have increased the risk of suicidal behavior (OR = 1.91), regardless of their ethnicity. In addition, the YWHAE*T allele of rs9393 polymorphism (OR = 2.21), YWHAE*T/*T genotype (OR = 2.73), and YWHAE*T allele (OR = 1.52) of the rs1532976 polymorphism, as well as the YWHAE*A*T haplotype of rs1532976 and rs9393 polymorphisms (OR = 1.54) represent genetic markers of the risk of suicidal behavior in the sample of subjects of Russian ethnicity.  相似文献   
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Insertion/deletion and VNTR polymorphisms of the serotonin transporter gene were tested for association with schizophrenia in patients of different ethnicity. A difference in genetic predisposition was observed for continuous and shift-like schizophrenia forms, the former tending to be associated with genotype 12/12 in Tatars and L/L in Russians.  相似文献   
17.
Mutations in three genes PSEN1, PSEN2, and APP are known to be a cause of familial forms of Alzheimer’s disease (AD). APOE gene polymorphism is a strong risk genetic factor for AD. We have evaluated allele and genotype frequency distribution of rs11136000 polymorphism in the clusterin (CLU) gene (or apolipoprotein J, APOJ) in the samples from three Russian populations and in AD patients. Genome-wide association studies in samples from several European populations have recently revealed the highly significant association of CLU gene with AD (p = 8.5 × 10?10). We found no differences in allele and genotype frequencies of rs11136000 between the populations from the Moscow, Ural, and Siberia regions. The allele frequencies are close to those in European populations. The genetic association analysis in cohort of AD patients and normal individuals (>500 individuals in each group) revealed no significant association of the rs11136000 polymorphism in CLU gene with Alzheimer’s disease in Russian populations. Although our results showed that the CLU gene polymorphism rs11136000 is likely not a major genetic factor for the common form of Alzheimer’s disease, the data do not rule out the possibility of a modest effect of CLU and interaction between CLU and APOE genotypes in etiology of Alzheimer’s disease.  相似文献   
18.
In this study, bornyl- and cytisine-based cyanopyrrolidines as potent dipeptidyl peptidase-IV (DPP-IV) inhibitors were synthesised. The in vitro inhibiting activities of bornyl- and cytisine derivatives towards DPP-IV were evaluated. Bornyl-based cyanopyrrolidines were shown to have moderate inhibitory activity with regard to DPP-IV (1.27–15.78?µM). A docking study was performed to elucidate the structure-activity relationship of the obtained compounds. The in vivo hypoglycemic activities of the same compounds were evaluated with the oral glucose tolerance test (OGTT) in mice. Bornyl-based cyanopyrrolidines were shown to have good hypoglycemic activity.  相似文献   
19.

Background

Noopept (N-phenyl-acetyl-L-prolylglycine ethyl ester) was constructed as a dipeptide analog of the standard cognition enhancer, piracetam. Our previous experiments have demonstrated the cognition restoring effect of noopept in several animal models of Alzheimer disease (AD). Noopept was also shown to prevent ionic disbalance, excitotoxicity, free radicals and pro-inflammatory cytokines accumulation, and neurotrophine deficit typical for different kinds of brain damages, including AD. In this study, we investigated the neuroprotective action of noopept on cellular model of AD, Aβ25–35-induced toxicity in PC12 cells and revealed the underlying mechanisms.

Results

The neuroprotective effect of noopept (added to the medium at 10 μM concentration, 72 hours before Аβ25–35) was studied on Аβ25–35-induced injury (5 μM for 24 h) in PC12 cells. The ability of drug to protect the impairments of cell viability, calcium homeostasis, ROS level, mitochondrial function, tau phosphorylation and neurite outgrowth caused by Аβ25–35 were evaluated.Following the exposure of PC12 cells to Аβ25–35 an increase of the level of ROS, intracellular calcium, and tau phosphorylation at Ser396 were observed; these changes were accompanied by a decrease in cell viability and an increase of apoptosis. Noopept treatment before the amyloid-beta exposure improved PC12 cells viability, reduced the number of early and late apoptotic cells, the levels of intracellular reactive oxygen species and calcium and enhanced the mitochondrial membrane potential. In addition, pretreatment of PC12 cell with noopept significantly attenuated tau hyperphosphorylation at Ser396 and ameliorated the alterations of neurite outgrowth evoked by Аβ25–35.

Conclusions

Taken together, these data provide evidence that novel cognitive enhancer noopept protects PC12 cell against deleterious actions of Aβ through inhibiting the oxidative damage and calcium overload as well as suppressing the mitochondrial apoptotic pathway. Moreover, neuroprotective properties of noopept likely include its ability to decrease tau phosphorylation and to restore the altered morphology of PC12 cells. Therefore, this nootropic dipeptide is able to positively affect not only common pathogenic pathways but also disease-specific mechanisms underlying Aβ-related pathology.  相似文献   
20.
Structural origins of fibrin clot rheology   总被引:9,自引:0,他引:9       下载免费PDF全文
The origins of clot rheological behavior associated with network morphology and factor XIIIa-induced cross-linking were studied in fibrin clots. Network morphology was manipulated by varying the concentrations of fibrinogen, thrombin, and calcium ion, and cross-linking was controlled by a synthetic, active-center inhibitor of FXIIIa. Quantitative measurements of network features (fiber lengths, fiber diameters, and fiber and branching densities) were made by analyzing computerized three-dimensional models constructed from stereo pairs of scanning electron micrographs. Large fiber diameters and lengths were established only when branching was minimal, and increases in fiber length were generally associated with increases in fiber diameter. Junctions at which three fibers joined were the dominant branchpoint type. Viscoelastic properties of the clots were measured with a rheometer and were correlated with structural features of the networks. At constant fibrinogen but varying thrombin and calcium concentrations, maximal rigidities were established in samples (both cross-linked and noncross-linked) which displayed a balance between large fiber sizes and great branching. Clot rigidity was also enhanced by increasing fiber and branchpoint densities at greater fibrinogen concentrations. Network morphology is only minimally altered by the FXIIIa-catalyzed cross-linking reaction, which seems to augment clot rigidity most likely by the stiffening of existing fibers.  相似文献   
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