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101.
粉防己碱舒张离体新西兰白兔阴茎海绵体平滑肌的机制研究 总被引:1,自引:0,他引:1
目的观察粉防己碱(tetrandrine,Tet)对阴茎海绵体平滑肌胞内钙释放和胞外钙内流的影响,初步探讨其舒张作用的机制。方法采用离体阴茎海绵体平滑肌肌条张力记录法,观察Tet对去氧肾上腺素(phenylephrine,PE)和氯化钾(KCI)诱导收缩的肌条的影响;采用无Ca~(2 )-复Ca~(2 )实验法,观察Tet对PE诱导的依赖细胞内钙和细胞外钙的肌条收缩反应的影响。结果Tet对PE或kcl诱导的肌条收缩均具有浓度依赖性的抑制作用。100μmol/L Tet可抑制20μmol/L PE引起的依赖细胞内钙和细胞外钙的肌条收缩(P<0.05);结论Tet可通过阻滞电压依赖性钙通道、受体依赖性钙通道和抑制细胞内钙库释放,从而介导其对海绵体平滑肌的舒张作用。 相似文献
102.
The effect associated with the substitution of adenine (A) for guanidine (G) in the promoter region of the apolipoprotein AI gene (?75 bp) with plasma apo AI and high-density lipoprotein (HDL) levels was investigated in the European Atherosclerosis Research Study (EARS). This is a study of healthy offspring (cases) of fathers who had suffered premature myocardial infarction (MI) before age 55 years (n = 565) and age- and sex-matched controls (n = 1,078) from 12 European countries, divided into 5 regions based on geography and language. The frequency of the polymorphism was not significantly different among the regions and the relative frequency of the rare A allele was similar in cases and controls (0.159 vs. 0.142) combining data from all regions. Individuals with one or more A allele had significantly higher plasma apo AI levels (P < 0.05) than individuals homozygous for the G allele. This effect was consistent in all regions. The data were analyzed separately in males and females. In females, those with one or more A allele had significantly higher apo AI levels (P = 0.05) than individuals homozygous for the G allele, and this raising effect of the A allele was greater in cases than controls for both apo AI (5.23% vs. 1.56%) and HDL (4.48% vs. 1.89%). In males, the A allele was associated with higher levels of apo AI and HDL, but the effect was much smaller and the differences did not reach statistical significance. In the females, where the effect of the A allele was strongest, the effect on apo AI associated with genotype was evident in non-smokers, and individuals with one or two A alleles had 3.6% higher apo AI and 3.14% higher HDL levels than individuals homozygous for the G allele. However, in the female smokers the raising effect of the A allele was greatly reduced (0.56%). Thus genetic variation in the promoter region of the apo AI gene is associated with differences in apo AI and HDL levels in healthy individuals throughout Europe, but the effect is modulated by gender, environmental factors such as smoking, and a family history of MI. 相似文献
103.
本实验采用家兔近端正中神经和尺神经原位移植法研究预防创伤性神经瘤形成之机理。经光镜,透射电镜及免疫组化标记观察表明:(1)自体神经原位移植法能有效地抑制创伤性神经瘤形成。两神经再生的神经纤维在移植段中排列整齐,来自两神经的轴索末端髓鞘对接是抑制创伤性神经瘤形成的关键;(2)移植段中由于雪旺氏细胞增生所形成的雪旺氏鞘对近端神经轴索的再生有趋化和引导作用;(3)单纯吻合法不能抑制创伤性神经瘤的发生。 相似文献
104.
上海市闵行区流动人口中的孕产妇保健状况 总被引:3,自引:0,他引:3
通过对上海市闵行区580名外来孕产妇及580名作为对照的本地孕产妇的孕产期保健现况调查分析,表明外来孕产妇缺乏必要的孕产期保健措施,有47.6%的外来孕产妇从未做产前检查,产后保健则完全没有,并由此而造成外来产妇在急产、死产、甚至孕产妇死亡等方面令人忧虑的现状。为适应和促进当前经济发展的新形势,改善流动人口的孕产妇保健状况,应对流动人口中孕产妇保健状况深入研究,并采取相应的措施。 相似文献
105.
麻醉犬静脉给血压灵5mg/kg,平均动脉压降低33.12%,降压作用持续4~5小时。本品50mg/kg分别给麻醉犬、大鼠及猫灌胃,其血压分别降低22.54%、26.38%及28.95%,作用均持续5~7小时。在常压清醒大鼠,以血压灵100mg/kg灌胃,每日2次,连续3天,其血压降低15.13%,持续48小时。以同等剂量给清醒原发性高血压大鼠灌胃,每天2次,连续6天,其血压降低14.31%降压作用持续72小时。本品降压作用部位在中枢,其轻度α受体阻断作用及直接舒血管作用可能也参与降压作用。 相似文献
106.
(张明敏)(刘沛霖)(叶望云)EffectofTripterygiumVilfordiionAdrenalCortexinRatwithAdjuvantArthritis¥ZHANGMing-min;LIUPei-lin;YEWang-yun(Tongji... 相似文献
107.
Li Ming Yang Jing Shen Guan-xin Zhang Qian Liu Shen-pei Liu Zhong-bei Ye Wei-xin 《华中科技大学学报(医学英德文版)》1994,14(4):209-212
Summary T cell activation and proliferation via CD3-TCR complex were investigated by lymphocyte DNA synthesis in vitro. Several interfering factors were also discussed. The
result indicated that lymphocyte activation and proliferation are calciumdependent. A rise of cytoplasmic free Ca2+ quickly following activation with CD3 McAb is mainly due to intracellular mobilization of Ca2+, while lymphocyte proliferation needs both intracellular mobilization of Ca2+ as well as influx of extracellular Ca2+. It was confirmed that CTX sensitive G protein plays a role in regulating T cell proliferation by pretreatment with CTX suppressing
lymphocyte3H-TdR incorporation obviously. PLC and PKC inhibitor neomycin and P. S. S could also decrease T cell proliferation. 相似文献
108.
M Hettiarachchi E Q Colquhoun J M Ye S Rattigan M G Clark 《International journal of obesity (2005)》1991,15(1):37-43
d,l-Norephedrine (phenylpropanolamine) which is both a demethylated analogue and a metabolite of d,l-ephedrine, is a reputed anorectic agent. In the present study the proposed most active isomer of this mixture, l-norephedrine has been assessed as a peripherally acting thermogenic agent in the isolated perfused rat hindlimb. l-Norephedrine produced a dose-dependent increase in oxygen uptake and perfusion pressure and increased lactate production. Whereas propranolol potentiated the increase in oxygen uptake and perfusion pressure produced by l-norephedrine, prazosin significantly and nitroprusside totally inhibited both of these changes. Nitroprusside also completely inhibited the increase in lactate production. We conclude that norephedrine has a hitherto unrecognized peripheral thermogenic activity in the perfused rat hindlimb resulting from its interaction with alpha 1 adrenergic receptors that control vasoconstriction in this tissue. 相似文献
109.
合肥市部分人群SARS认知及行为态度 总被引:4,自引:1,他引:3
目的 了解合肥市部分人群对 SARS的认知情况及行为态度。方法 对合肥市两个社区及一所大学的部分人群共 1332人进行现况调查 ,比较不同性别、职业、文化程度对 SARS的总体认知水平。结果 合肥市人群对 SARS的认知情况尚好 ,总体平均得分 ( 15 .0 2± 1.98)分 (总分 18分 )。结论 合肥市居民对 SARS的认知水平总体较高 ,但存在群体差异 ,卫生行政部门应加强对公众的宣传教育 ,以提高全体居民的健康意识 ,进而预防 SARS的发生 相似文献
110.
Preventionofadhesionofrabbitkneejointwithchitosan:anexperimentalstudyYeGenmao(叶根茂);HouChunlin(侯春林)(DepartmentofOrthopaedics,C... 相似文献