人参皂甙对大鼠输精管和肛尾肌中α受体效应的影响

人参皂甙(G,10~(-4)g/ml)对离体大鼠输精管(RVD)的正常张力无影响,但能增强电场刺激引起的RVD收缩效应,对抗可乐定(Clo)抑制和育亨宾(Yoh)增强电场刺激引起的RVD收缩。G使苯福林(Phe)对RVD和肛尾肌(RAM)α_1受体作用的量效曲线右移。上述结果进一步支持G在突触前后膜α受体水平上可能均起着调谐剂(modulator)样作用的观点。     

Pharmacological characterization of the postjunctional beta-adrenoceptors in the rat gastric fundus

In order to characterize the postjunctional beta-adrenoceptors in the rat gastric fundus, we studied the influence of beta-agonists and beta-antagonists on methacholine-contracted fundus strips. The mixed beta-agonist isopropylnoradrenaline and the beta 2-selective agonist fenoterol had a concentration-dependent relaxing effect and at higher concentrations completely inhibited the methacholine-induced tone. The reputedly beta 1-selective agonist prenalterol only produced about 50% inhibition and another reputedly beta 1-selective agonist, tazolol, had almost no relaxing effect. The beta-antagonists propranolol (beta 1 + beta 2), practolol (beta 1), H35/25 (beta 2) and ICI 118,551 (beta 2) all shifted the concentration-response curves for isopropylnoradrenaline and fenoterol in a parallel way to the right, but the slope of the Schild plot was not significantly different from 1 only for the antagonism of isopropylnoradrenaline by H35/25. The relaxing effect of prenalterol was only clearly antagonized by ICI 118,551. The results suggest that postjunctional beta 1- and beta 2-adrenoceptors are present in the rat gastric fundus.     

Animal protection and toxicity testing regulations

Safety testing illustrates a very real ethical dilemma between our moral obligations to protect humans and to protect animals from harm. The pragmatic approach to resolving this conflict is to pursue the 3 Rs of Replacement, Reduction and Refinement. Safety tests set out in regulation protocols often conflict with this ethic, being wasteful in numbers of animals used, having unnecessarily severe end-points and resulting in duplication. Suggestions for refinement of these tests are discussed. It is concluded that such refinement could lead to the generation of more meaningful data, thus improving both animal protection and human safety.     

Cardiac and subjective response to cognitive challenge and to controlled physical exercise by male and female coronary prone (Type A) and non-coronary prone persons

Male and female subjects who were classified as either Type A or Type B took a cognitive test (digit symbol) and also participated in an exercise task in which they stepped up and down a step in time to a pace established by the experimenter. Results indicated that prior to the IQ test there were no differences between Type A and Type B subjects in heart rate or subjective arousal. During the IQ test, Type A subjects showed a higher heart rate than Type B subjects, and that effect was most pronounced among males (A-males had rates that were 20.3 b.p.m. higher than their resting level and 14.6 b.p.m. higher than B-males). Although during the IQ test Type A subjects had higher heart rates than Type B subjects, they did not report higher subjective arousal. Type A and Type B subjects did not show different heart rate responses to the controlled physical exercise.     

Assessing debt-to-health swaps: a case study on the Global Fund Debt2Health Conversion Scheme

The Debt2Health Conversion Scheme of the Global Fund to Fight AIDS, Tuberculosis and Malaria is used to reassess a range of recent initiatives that propose debt relief in exchange for spending in the health sector. The experience with debt swaps in the mid 1990s was far from positive, and recent improved insight in the economics of debt relief suggests extreme caution. We argue that the recent spade of debt swap proposals, even if targeting countries and debt titles that fall outside current major international debt relief mechanisms, share most of the design faults of previous initiatives. Proposals such as Debt2Health do not constitute efficient vehicles to increase net transfers to poor countries, to reduce the economic disadvantages of indebtedness, or to strengthen public health systems of partner countries. For debt relief to constitute a valuable mechanism to provide aid, it should be designed as a large-scale and comprehensive operation, with spending earmarked to broad country-established priorities, and reinforce rather than undermine national implementation systems.     

心肌梗死患者认知功能障碍的研究进展

冠心病是全球主要的死亡原因,急性心肌梗死是最常见的心血管疾病。心肌梗死与认知障碍之间可能存在相关性,但目前尚不清楚心肌梗死导致认知能力下降的确切机制。心肌梗死合并认知障碍对疾病的预后产生不良影响,且患者长期预后不容乐观可能与治疗不充分有关。随着人口老龄化和医疗干预手段的增加,需要制定具体策略来提高治疗效果。本文对心肌梗死患者认知障碍的发生机制,对终点事件的影响及治疗策略的研究进展进行综述。     

右美托咪定对老年患者围术期神经认知功能障碍的影响

围术期神经认知功能障碍是老年患者术后常见的并发症,不仅增加患者住院时间、还会增加经济负担.它的发生可能与无菌手术或麻醉介导的炎症反应、血脑屏障受损、中枢神经系统炎症反应、胶质细胞激活、氧化应激及中枢神经系统相关通路激活和神经递质的释放等因素有关.右美托咪定是一种高选择性α2-肾上腺受体激动剂,自美国食品药品监督管理局批...     

肺癌住院患者衰弱患病率及其影响因素

目的 调查肺癌住院患者衰弱患病率,并进一步分析其相关影响因素。方法 连续定点纳入2021年12月至2022年4月北京协和医院符合纳入及排除标准的肺癌住院患者,收集其一般人口学资料、病史资料、营养相关资料及实验室检查资料。采用Fried衰弱表型评估衰弱状况,采用营养风险筛查2002进行营养风险筛查,采用多频生物电阻抗法测定人体成分。采用Stata/SE 16.0软件进行数据分析。根据数据类型,组间比较分别采用χ²检验及方差分析。结果 共纳入肺癌患者109例,其中衰弱39例(35.8%),衰弱前期45例(41.3%),非衰弱25例(22.9%)。病理类型为小细胞肺癌、患有共病、有营养风险的患者其衰弱患病率显著升高,差异均有统计学意义(χ²=6.38,14.25,12.02;均P＜0.05)。多因素logistic回归分析显示,共病数、肌肉量、美国东部肿瘤协作组体力状况评分和血清白蛋白含量是衰弱和衰弱前期的独立影响因素(β=0.653、-0.980,1.169,-0.128;均P＜0.05)。结论 肺癌住院患者普遍处于衰弱或衰弱前期。患者的共病情况、营养状况、肌肉量及活动能力与衰弱状况有密切关联。     

体质量指数与老年阻塞性睡眠呼吸暂停低通气综合征严重程度的相关性

目的探讨体质量指数(BMI)与老年阻塞性睡眠呼吸暂停低通气综合征(OSAHS)严重程度的相关性。方法回顾性分析2015年1月至2017年10月在解放军总医院、北京大学国际医院和甘肃中医药大学附属医院经标准多导睡眠监测诊断为OSAHS的609例老年患者(≥60岁)的病例资料。按BMI水平将研究对象分为体重正常组(n=154)、超重组(n=228)和肥胖组(n=227),比较组间多导睡眠监测指标的差异。采用SPSS 25.0软件进行数据分析。采用Spearman秩相关分析BMI与多导睡眠监测主要指标的相关性,采用多因素logistic回归分析不同BMI水平与重度OSAHS的相关性。结果3组患者呼吸暂停低通气指数(AHI)、血氧饱和度(SaO2)<90%的时间、氧减指数(ODI)、平均暂停时间、最低氧饱和度、平均氧饱和度与SaO2<90%的时间占总监测时间比例(T90)比较,差异均有统计学意义(均P<0.05);老年OSAHS患者的BMI与AHI、最长暂停时间、ODI、T90、SaO2<90%的时间呈正相关(r=0.294、0.113、0.313、0.413、0.411,均P<0.05),与平均氧饱和度、最低氧饱和度呈负相关(r=-0.173、-0.229,均P<0.05);超重组罹患重度OSAHS的风险是正常体重组的1.690倍(OR=1.690),肥胖组罹患重度OSAHS的风险更高(OR=3.685)。分层分析(高血压和无高血压)发现,肥胖与重度OSAHS的相关性在高血压和非高血压人群中均存在,但在非高血压人群中,肥胖与重度OSAHS的相关性更强。结论老年人BMI越大,OSAHS病情越严重。非高血压人群中BMI和老年OSAHS的严重程度相关性更强。     

老年男性人群高血压合并糖耐量减低与全因死亡风险的相关性

目的 探讨高血压合并糖耐量减低(IGT)对老年男性人群全因死亡风险的影响。方法 纳入2005年5月至2007年5月在解放军总医院第二医学中心行口服葡萄糖耐量试验检出的老年男性IGT患者和正常糖耐量(NGT)人群,根据基线时是否存在高血压病史和IGT分为4组:非高血压(NH)+正常糖耐量(NGT)组、高血压(H)+NGT组、NH+IGT组、H+IGT组,每年至少随访1次。采用SPSS 13.0统计软件进行数据分析。采用Cox回归模型分析不同组别全因死亡风险的差异。结果 与NH+NGT组比较,H+IGT组(HR=2.55,95%CI 1.56-4.16; P<0.001)和NH+IGT组(HR=2.40,95%CI 1.35-4.25; P=0.003)2型糖尿病发病风险显著升高。单因素Cox比例风险回归分析提示,与NH+NGT组比较,H+IGT组(HR=2.59,95%CI 1.34-5.01; P=0.005)全因死亡风险明显升高,而H+NGT组和NH+IGT组无统计学差异(P>0.05)。在调整相关危险因素后多因素Cox比例风险回归分析显示,H+IGT组(HR=1.83,95%CI 0.90-3.70; P=0.095)全因死亡风险较NH+NGT组虽无统计学差异(P>0.05),但有升高的趋势。结论 老年男性人群高血压合并IGT与全因死亡风险密切相关,高血压与IGT并存可导致全因死亡风险增加。