Autonomic nervous system mediates the cardiovascular effects of Rhodiola sacra radix in rats

ETHNOPHARMACOLOGICAL RELEVANCE: Rhodiola sacra (Crassulaceae) exhibits cardiovascular bioactivities and is used in Tibetan medicine for promoting circulation and preventing hypertension. However, the underlying mechanisms of its cardiovascular effects are poorly understood. AIM OF THE STUDY: The aim of this study was therefore to evaluate the cardiovascular activity of water-soluble fraction (WtF) and n-butanol-soluble fraction (BtF) of Rhodiola sacra radix and to explore its mechanism of action in propofol anesthetized Sprague-Dawley rats. MATERIALS AND METHODS: The changes of blood pressure, heart rate and cardiac contractility after systemic administration of the extracts (10-75mg/kg) were examined for at least 40min. Different antagonists were used to evaluate the mechanisms of cardiovascular effects of the extracts. RESULTS: Intravenous injection of the WtF (10, 25, 35, 50 or 75mg/kg) exhibited dose-dependent hypotension and increases in heart rate and cardiac contractility. In contrast, mild alterations in the same cardiovascular parameters were detected only at high dose (75mg/kg) BtF. The WtF-induced hypotensive, positive inotropic and chronotropic effects were significantly abolished by pretreatment with hexamethonium (30mg/kg, i.v.) or reserpine (5mg/kg, i.v.), whereas the hypotensive, but not the positive inotropic or chronotropic effect was potentiated by captopril (2.5mg/kg, i.v.). Pretreatment with methylatropine (1mg/kg, i.v.), on the other hand, reversed the positive inotropic and chronotropic but not the hypotensive effects of WtF. The WtF-induced cardiovascular responses were not affected in rats pretreated with N(G)-nitro-l-arginine methyl ester (20mg/kg, i.v.). CONCLUSIONS: We conclude that systemic administration of the WtF of Rhodiola sacra radix elicited a potent hypotensive effect that was mediated by the withdrawal of sympathetic vasomotor tone and interaction with the circulatory angiotensin system. The positive inotropic and chronotropic effects of WtF may result from a direct vagal inhibition on the heart.     

MRI常规序列、SWI序列及DWI在脑外伤微出血患者诊断中的应用研究

目的 探究MRI常规序列、SWI序列以及DWI序列在脑外伤微出血患者诊断中的应用价值。方法 选取2019年8月～2020年4月我院收治的71例脑外伤微出血患者作为观察对象,所有患者在入院3天后行头部MRI常规序列(T₁WI、T₂WI、T₂FLAIR)、扩散加权成像(DWI)序列及磁敏感加权成像(SWI)序列检查。观察脑外伤微出血病灶在不同扫描序列中的影像学表现,对比不同扫描序列对脑外伤微出血病灶的检出率。结果 微出血病灶在T₁WI序列中多表现为大小不等的斑片状、条状等、低信号影,T₂WI、T₂FLAIR序列中多为稍高信号或等信号,DWI序列中多表现为低信号或等信号。微出血病灶在SWI序列中多为点状、斑片状、类圆形或环形低信号影,与T₁WI、T₂WI、T₂FLAIR等MRI常规序列以及DWI序列相比,SWI对微出血病灶的显示更加明显,所显示的微出血病灶更多,病灶边缘更加清晰,病灶范围更大。71...     

Weighted Markov chains for forecasting and analysis Incidence of infectious diseases in jiangsu Province,China

This paper first applies the sequential cluster method to set up the classification standard of infectious disease incidence state based on the fact that there are many uncertainty characteristics in the incidence course.Then the paper presents a weighted Markov chain,a method which is used to predict the future incidence state.This method assumes the standardized self-coefficients as weights based on the special characteristics of infectious disease incidence being a dependent stochastic variable.It also analyzes the characteristics of infectious diseases incidence via the Markov chain Monte Carlo method to make the long-term benefit of decision optimal.Our method is successfully validated using existing incidents data of infectious diseases in Jiangsu Province.In summation,this paper proposes ways to improve the accuracy of the weighted Markov chain,specifically in the field of infection epidemiology.     

药品知识产权国际保护的中庸之道

药品知识产权国际保护中存在着多重权利冲突，其中最为突出的就是专利权与生命健康权的对立。试从伦理的角度来审视药品知识产权，以中庸之道来解决药品知识产权国际保护中的权利冲突与道德困境。一方面，作为私权与财产权的药品专利权并没有与更优于它的其他权利发生冲突时，应该保护药品专利权并努力促使这一权利得以实现；另一方面，当药品专利权与位阶上更优于它的生命健康权相冲突时，专利权应让位与生命健康权，作出必要的自我牺牲。在具体实践中，药品知识产权国际保护应尊重差别原则，建立相应的专利药品价格差别制度，高扬救死扶伤的人道精神以维护生命健康权。     

Temporal variability of blood lead,mercury, and cadmium levels in elderly panel study (2008–2014)

Background

Biological measurements have been employed as useful biomarkers for exposure. Because of its property of reflecting toxicokinetic differences, however, within-subject variability leads to biased results in epidemiologic studies.

生产场所矽尘环境瞬时浓度与时间加权平均浓度关系的研究

[目的 ]探讨生产场所矽尘环境瞬时浓度 (EIC)与其时间加权平均浓度 (TWA)间的关系。 [方法 ]在铸造厂、耐火材料厂和锡矿同时测定矽尘EIC和TWA。提出理想瞬时浓度的概念 ,基于理想瞬时浓度及其取值集合S的共同框架来分析EIC与TWA两者的关系 ,推导出TWA理论 =μeσ2 / 2 。以该公式将上述 3家厂矿EIC换算为理论TWA ,并与相应TWA实测值比较。 [结果 ]理论与实测TWA间的差别在耐火材料厂和锡矿均无显著性 (t =1.961和t =1.746,均P >0 0 5 ) ,该公式成立 ,而在铸造厂则否 (t=7.772 ,P <0 .0 5 )。 [结论 ]生产性矽尘EIC与TWA之间在多数情况下存在一定的函数关系 ,经TWA理论 =μeσ2 / 2可将EIC转换为TWA ,这对于我国制订粉尘职业接触限值时确定其TWA限值 ,以及对于TWA的上限值容许上移多少这一国际上有争论的问题均有指导作用     

综合评价医院工作的指标加权百分位次累加法

本文提出了综合评价医院工作的一种方法——指标加权百分位次累加法。本方法分五个步骤:1.建立评价指标体系;2.制定评价标准值;3.对指标值进行标准化;4.根据指标重要程度赋予相应权重;5.进行综合评价。并通过实际资料对本方法进行了验证。     

磁共振弥散加权成像在临床中的应用

目的:探讨磁共振弥散加权成像在临床中的应用。方法:阅读有关磁共振弥散加权成像的文献资料。结果:磁共振弥散加权成像在急性脑缺血性疾病、脑肿瘤、脑脓肿的分期[2]、肝脏肿瘤、鉴别乳腺肿瘤的良恶程度以及椎体病变的诊断上发挥了重要作用,但在应用中仍有一定局限性。结论:磁共振弥散加权成像将在临床疾病的诊断、鉴别诊断中发挥越来越大的作用。     

以CD54为评价指标的THP-1细胞光致敏体外评价方法的确定和验证

目的 确定并验证以细胞表面标志物CD54作为评价指标的光致敏体外评价方法。方法 将THP-1细胞与多种光致敏剂、光刺激剂、皮肤致敏剂、皮肤刺激剂和阴性受试物分别孵育,在光照射或避光处理后,用流式细胞仪测定细胞表面标志物CD54和CD86的表达水平并统计分析,进一步确定具体的评价指标,并对该方法的准确性、特异性、灵敏度、重复性进行验证。结果 19种光致敏剂中有15种引起照射组THP-1细胞表达CD54的平均荧光强度（MFI）较非照射组显著增加（P<0.05、0.01） ,且照射组细胞表达CD54的相对荧光强度（RFI）值均在1.5以上。光刺激剂经光照射后也可引起细胞表达CD54的MFI显著增加（P<0.01） ,但经过预照射处理后,CD54的表达水平较直接照射组显著下降（P<0.01）。未经光照射条件下,皮肤致敏剂即可引起THP-1细胞表达CD54和CD86的MFI比对照组显著增加（P<0.01） ,光照后CD54的表达反而略有下降。在光照和避光条件下,皮肤刺激剂、阴性受试物（乳酸）均未引起细胞表达CD54或CD86的显著性变化。以CD54为评价指标的THP-1细胞光致敏评价方法检测光致敏剂的准确性、特异性和灵敏度分别是85.2%、100%和78.9%,具有良好的重复性。结论 确定了THP-1细胞光致敏评价方法的细胞表面标志物评价指标为CD54,判定标准为：（1）光照后THP-1细胞表达CD54的MFI较照射前显著性增加;（2）光照后THP-1细胞表达CD54的RFI≥1.5;（3）当上述条件均满足时,对受试物进行预照射处理,结果仍然满足前2条标准。