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991.
甲硫氨酸脑啡肽对抗体的产生和T细胞免疫功能具有调节作用。为了明确这种作用机制,本实验观察了抗体和白细胞介素-2(IL-2)的产生和基因表达。甲硫氨酸脑啡肽对3F3杂交瘤细胞的抗体产生及其轻链和重链基因表达影响不明显。较高浓度的甲硫氨酸脑啡肽(0.1nmol·L ̄(-1)-1μmol·L(-1))不仅促进IL-2的产生和IL-2mRNA的转录,而且能提高IL-2mRNA的稳定性。 相似文献
992.
阿昔洛韦片剂和胶囊在人体的生物利用度 总被引:2,自引:0,他引:2
10名男性受试者按交叉实验设计口服阿昔洛韦片剂和胶囊各400 mg 后,用改良的 HPLC 测定血药浓度,计算表明阿昔洛韦胶囊口服后吸收快于片剂,峰浓度也较高,但吸收程度(AUC_(0-12h))相似。 相似文献
993.
对老年慢性肾功能衰竭264例患者(男148例,女116例;年龄66±7a)用硝苯啶10mg联合覆醛氧化淀粉5-10mg,tid,po。另设相似88例患者(男48例,女40例;年龄66±7a)单服覆醛氧化淀粉与之对照,用法同前。2组均连服16wk。结果:前者有效216例(81.8%),后者有效49例(56%),组间比较P<0.01。2组副作用相似,均可坚持服药。 相似文献
994.
本实验应用流式细胞光度术研究鼻咽癌上皮样细胞株(CNE)的细胞周期动力学。结果发现CNE细胞仍保持原代细胞的DNA含量水平(超三倍体和亚四倍体),随着细胞接种时间的延长细胞周期中G0/G1时相细胞的百分数逐渐升高,而S%和G2+M%则逐渐降低。该项研究还发现随着孵育时间的延长,细胞周期中各时相细胞的运动均逐渐延缓,其中以G0/G1和G2+M时相细胞的运动减慢较为明显。 相似文献
995.
凝血因子Ⅷ(FⅧ)由vWF和FⅧ:C组成。FⅧ:C的合成部位至今尚未确认。本文检测了16~22周胎龄胎儿肝、脾、肾及肾小球组织中Ⅷ:C活性及vWF:Ag含量后,发现肾中Ⅷ:C活性较高(1.679±1.588 U/ml),尤其是肾小球中高达46.313±40.651U/ml,脾中次之(0.372±0.462 U/ml),肝中最低(0.021±0.029U/ml)。将3种组织细胞培养后,发现仍以肾中Ⅷ:C活性最高。由此提示,肾可能是Ⅷ:C的合成部位。同时检测三器官中vWF:Ag,发现含量极微。这些组织中Ⅷ:C与vWF的关系有待研究。 相似文献
996.
HIROSHI KATAOKA JORGE P. LI ALFRED S.T. LUI STEVEN J. KRAMER DAVID A. SCHOOLEYS 《Chemical biology & drug design》1992,39(1):29-35
The locations of the three disulfide bonds of eclosion hormone (EH) isolated from Manduca sexta were assigned by sequence analysis of thermolysin fragments and by comparison of a key heterodimeric fragment to regiospecifically synthesized parallel and antiparallel isomers. We elucidated the complete structure of Manduca EH as a 62-residue peptide which has three disulfide bonds between Cys14-Cys38, Cys18-Cys34, and Cys21-Cys49. 相似文献
997.
Guan Xinmin Zhang Jian Shi Bo** Ouyang Xingbiao Research Department of Acupuncture Anesthesia Mechanism & Department of Neurobiology Tongji Medical University Wuhan China Department of Physiology Jinzhou School of Health Jinzhou Liaoning Province China 《世界针灸杂志》1993,(1)
For investigating the effect of acupuncture on ischemic arrhythmia and its mech-anism, adult albino rats with ligated anterior descending branch of coronary artery as experimentalmodel were treated with or without acupuncture, and others with imitative operation but without bothcoronary artery ligation and acupuncture treatment were used as control. It was found in acupuncturegroup that the fibrillation-liability of ischemic myocardium was efficiently decreased, the affinity ofAch-M receptors on membranes of ischemic myocardium was markedly increased, and the tolerance ofischemic myocardium to atropine was elevated in the experiment of atropine inducing fibrillation.These results indicate that acupuncture may play a therapeutic role on ischemic arrhythmia throughactivating the activity of muscarine-like receptors of cholinergic nervous system. 相似文献
998.
目的观察灯盏花素(BRE)对大鼠心肌缺血再灌注(I/R)诱导细胞凋亡及凋亡相关基因Bcl-2、Bax表达的影响,并对其作用机制进行初步探讨。方法30只SD大鼠随机分为3组(n=10):①假手术(Sham)组:前降支穿线不结扎,观察1.5 h;②缺血再灌注(I/R)组:结扎前降支30 m in,再灌注前5 m in生理盐水(4 mg/kg)iv,再灌注1h;③BRE组:再灌注前5 m in应用BRE(4 mg/kg)iv,余同I/R组。常规方法检测丙二醛(MDA)含量、超氧化物歧化酶(SOD)活性,免疫组化法测定Bc l-2、Bax蛋白的表达,通过细胞图像分析系统测量细胞阳性染色面积百分率,应用透射电镜观察心肌超微结构的变化。结果同I/R组相比,BRE组心肌组织MDA含量显著降低[(7.56±1.67)μmol/gvs(16.58±2.59)μmol/g,P<0.05],SOD活性显著升高[(2.37±0.22)mkat/gvs1.38±0.14 mkat/g,P<0.05],Bax蛋白表达显著降低(5.02±1.01vs18.59±5.68,P<0.01),而Bc l-2蛋白表达显著增高(17.48±4.72vs7.32±2.05,P<0.01),Bax/Bc l-2显著降低(0.29±0.57vs3.32±0.10,P<0.01),细胞阳性染色面积百分率显著减少(0.42±0.06vs13.84±1.97,P<0.01),细胞超微结构损伤明显减轻。结论BRE通过调控Bax/Bc l-2表达抑制心肌I/R诱导的细胞凋亡,对缺血再灌注心肌具有保护作用。 相似文献
999.
Cécile Viboud Pierre-Yves Bo?lle Simon Cauchemez Audrey Lavenu Alain-Jacques Valleron Antoine Flahault Fabrice Carrat 《The British journal of general practice》2004,54(506):684-689
BACKGROUND: Influenza transmission in households is a subject of renewed interest, as the vaccination of children is currently under debate and antiviral treatments have been approved for prophylactic use. AIMS: To quantify the risk factors of influenza transmission in households. DESIGN OF STUDY: A prospective study conducted during the 1999 to 2000 winter season in France. SETTING: Nine hundred and forty-six households where a member, the index patient, had visited their general practitioner (GP) because of an influenza-like illness were enrolled in the study. Five hundred and ten of the index patients tested positive for influenza A (subtype H3N2). A standardised daily questionnaire allowed for identification of secondary cases of influenza among their household contacts, who were followed-up for 15 days. Of the 395 (77%) households that completed the questionnaire, we selected 279 where no additional cases had occurred on the day of the index patient's visit to the GP. METHODS: Secondary cases of influenza were those household contacts who had developed clinical influenza within 5 days of the disease onset in the index patient. Hazard ratios for individual clinical and demographic characteristics of the contact and their index patient were derived from a Cox regression model. RESULTS: Overall in the 279 households, 131 (24.1%) secondary cases occurred among the 543 household contacts. There was an increased risk of influenza transmission in preschool contacts (hazard ratio [HR] = 1.85, 95% confidence interval [CI] = 1.09 to 3.26) as compared with school-age and adult contacts. There was also an increased risk in contacts exposed to preschool index patients (HR = 1.93, 95% CI = 1.09 to 3.42) and school-age index patients (HR = 1.68, 95% CI = 1.07 to 2.65), compared with those exposed to adult index cases. No other factor was associated with transmission of the disease. CONCLUSION: Our results support the major role of children in the dissemination of influenza in households. Vaccination of children or prophylaxis with neuraminidase inhibitors would prevent, respectively, 32-38% and 21-41% of secondary cases caused by exposure to a sick child in the household. 相似文献
1000.
剥脱性半月板损伤的临床总结--20例临床病例分析 总被引:1,自引:0,他引:1
目的分析半月板的损伤的诊疗情况.方法回顾性研究1989~2003年20例剥脱性半月板损伤的临床表现、诊断治疗情况.结果2例行保守治疗,3例行手术修补,15例行切除治疗.结论内侧半月板常为部分剥脱损伤可以保守治疗,外侧半月板多为完全性剥脱损伤,部分剥脱者可行修复治疗,完全性剥脱损伤者可行全切手术治疗.最佳处理方式是精确诊断、及时治疗,根据损伤的具体情况可采用保守治疗,若需手术应尽可能的实施非切除处理. 相似文献