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排序方式: 共有842条查询结果,搜索用时 15 毫秒
831.
It is widely appreciated that the vascular endothelium is capable of modulating vascular smooth muscle tone suiting it well for its role as an important regulator of a number of diverse biological processes. Endothelial dysfunction is an early manifestation of atherothrombosis and a consequence of the established disease. Although several arginine derivatives alkylated at one of the guanidino nitrogen were found to inhibit vasorelaxation induced by acetylcholine, activity of the corresponding arginine esters is not reported. The present work was therefore designed to synthesize and evaluate series of novel arginine derivatives to obtain further insight into structure-activity relationship in this series of compounds. Present study involves assessment of activity of these novel compounds on the vascular tone of rat thoracic aorta in comparison with l-arginine analog, that is, l-nitro-arginine methyl ester (l-NAME). Results from the present study showed that full reversal of phenylephrine-mediated contraction was achieved by cumulative applications of acetylcholine (3nm-300μm), which were abolished when the aortic rings were pretreated with l-NAME (300μm). Results from the present study demonstrated that these novel arginine derivatives cause significant yet reversible reduction in acetylcholine-mediated relaxation, similar to that of L-NAME. 相似文献
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833.
Yellow mosaic disease in grain legumes in Indian subcontinent is caused by two important virus species viz. Mungbean yellow mosaic virus (MYMV) and Mungbean yellow mosaic India virus (MYMIV), belonging to the genus Begomovirus of the family Geminiviridae. The genomic components of a begomovirus causing yellow mosaic disease in blackgram in southern India were cloned and sequenced.
Nucleotide sequence comparison of DNA A component shows the virus isolate to be a variant of Mungbean yellow mosaic virus:–(MYMV-[IN:Vam:05]). However, DNA B component of the present virus isolate has greater similarity (92%) to Mungbean yellow mosaic India virus. Agroinoculations of the viral clones produced typical yellow mosaic symptoms in blackgram and mungbean, severe leaf curl
and stunting in French bean, similar to blackgram isolate of MYMIV. Blackgram isolates of both the virus species were only
mildly infectious on cowpea, produced atypical leaf curl symptoms and not yellow or golden mosaic. In agroinoculations done
by exchanging genomic components, symptom expression was seen only in French bean. In cowpea, blackgram and mungbean there
was no visible symptoms though viral DNA could be detected by PCR. 相似文献
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836.
McGlade N Behan C Hayden J O'Donoghue T Peel R Haq F Gill M Corvin A O'Callaghan E Donohoe G 《The British journal of psychiatry : the journal of mental science》2008,193(1):77-78
Theory of mind deficits in schizophrenia have been parsed into mental state reasoning and mental state decoding components. We report that mental state decoding as measured by the 'Eyes task' better predicted social function than mental state reasoning as measured by the 'Hinting task' in 73 out-patients with chronic schizophrenia. Mental state decoding task performance also partly mediated the influence of basic neuropsychological performance on social function. We discuss these findings in terms of the accumulating evidence that mental state decoding has particular relevance for understanding deficits in social function in schizophrenia. 相似文献
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839.
Bashir Ahmad Akhtar Alam M.Sultan Bhat Khurshid Ahmad Bhat Jeelani Inaam ul Haq Hakim Farooq Ahmad Junaid Qadir 《国际灾害风险科学学报(英文版)》2021,(5):635-648
Disaster scenarios are constructed by integrating natural hazard phenomena and social science sources of information.We profiled 51 natural hazard events of nin... 相似文献
840.
Elizabeth Mova Hamilton Wadie Rassam Yan Yan Avjit Singh Sarah Yoon Ai Ng Jiabi Zhang Jun Lv Nazrul Islam Reem Malouf Ling Yang Iona Y. Millwood Zhengming Chen 《Journal of viral hepatitis》2023,30(6):470-488
Chronic infection with hepatitis B virus (HBV) is a significant public health issue in China. Understanding factors associated with chronic HBV is important to enable targeted screening and education and to improve early diagnosis and prevention of disease progression. This systematic review and meta-analysis aimed to identify and describe correlates of chronic HBV among Chinese adults. Searches were conducted in MEDLINE, EMBASE and grey literature up to 25 June 2020. Eligible papers included observational studies in adults of the general population in China that reported factors associated with chronic HBV, measured by Hepatitis B surface antigen (HBsAg). Meta-analysis was performed using fixed-effect models of HBsAg prevalence among factors, and of adjusted odds ratios (ORs) for chronic HBV associated with each factor. Overall 39 articles were included, covering 22 factors, including a range of sociodemographic, behavioural and medical factors. In meta-analysis of eligible studies, a range of factors were significantly associated with higher HBsAg prevalence, including middle age, male sex, being married, rural residence, lower education, smoking, having a HBsAg positive household contact, family history of HBV, history of surgery or blood transfusion. The adjusted ORs varied, from 1.11 (95% CI 1.05–1.18) for smoking to 5.13 (95% CI 4.99–5.26) for having a HBsAg positive household contact. In Chinese adults, a range of factors are associated with chronic HBV infection, which may help inform targeted screening in the general population. 相似文献