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41.
ATP和SNP控制性降压对血流动力学的影响   总被引:1,自引:1,他引:0  
对比研究三磷酸腺苷(ATP)和硝普钠(SNP)控制性降压对氯胺酮麻醉犬血流动力学的影响。选择犬14只,随机分为ATP组和SNP组,由股静脉持续输入ATP和SNP使MAP降低30% ̄40%,维持30min,分别于降压前、降压后15min、30min及停止降压后15min用Swan-Ganz漂浮导管测定血流动力学指标。结果表明,ATP、SNP降压期间SVR、LVSW显著降低,CO、PCWP、SV、RV  相似文献   
42.
近年来的研究结果发现由Th1/Th2细胞分泌的淋巴因子与妊娠高血压综合征联系密切 ,可能参与了其病因及病理生理过程 ,对它的深入研究有利于妊娠高血压综合征诊断、治疗水平的提高  相似文献   
43.
用9周-39周引产胎儿标本72例,取右耳廓石蜡切片,HE和Weitert弹性纤维染色,光镜观察其弹性软骨、弹性纤维、耳廓肌和结缔组织的发生。  相似文献   
44.
目的 :对腹腔镜下治疗输卵管妊娠手术做出评价 ,并与传统剖腹手术方法比较。方法 :在电视腹腔镜下行保守性手术 8例及根治性手术 2 0例 ;对照组 2 8例采用传统剖腹手术方法。结果 :两组手术时间、尿TT恢复正常时间、切口感染差异均无显著性 (P >0 .0 5 ) ,两组术中出血、术后体温、肛门排气时间、下床活动时间、住院天数差异有显著性 (P <0 .0 1)。结论 :腹腔镜下治疗输卵管妊娠术具有创伤小 ,康复快 ,术中出血少 ,术后感染率低等优点 ,有助于提高患者生活质量 ,是临床上的理想手术方式  相似文献   
45.
The genetic basis for addiction to tobacco smoking--particularly that of the perception of olfactory stimuli that may be important in reinforcing smoking addiction--is largely unknown. A cluster of genes for olfactory receptors is in close proximity to the MHC region on chromosome 6. Polymorphisms of MHC class III genes (RCCX modules, TNFA promoter polymorphisms) were determined in 101 healthy subjects and 232 coronary artery disease (CAD) patients from Hungary with defined tobacco smoking habits. A highly significant association between ever smoking (past + current smokers) and a specific MHC haplotype was observed (odds ratios = 2.14-4.13; P-values = 0.012 to <0.001). This haplotype is characterized by the presence of C4A null alleles and a solitary short C4B gene linked to the TNF2 allele of the promoter for TNFA gene. This haplotype occurred more frequently in the ever smokers than in the never smokers [odds ratio: 4.97 (1.96-12.62); P = 0.001], and such associations were stronger in women (odds ratio = 13.6) than in men (odds ratio = 2.79). An independent study of complement C4 protein polymorphism and smoking habits in Icelandic subjects (n = 351) yielded similar and confirmative results. Considering the documented link between olfactory stimuli and smoking in females, and the presence of a cluster of odorant receptor genes close to the MHC class I region, our findings implicate a potential role of the MHC-linked olfactory receptor genes in the initiation of smoking.  相似文献   
46.
Platelet adhesion: a comparison of four methods   总被引:3,自引:0,他引:3  
  相似文献   
47.
48.
The Dynabeads method showed the potential for enumerating CD4 T lymphocytes (CD4 count) in HIV-1-infected individuals. The large volume of Dynabeads required for 1 sample and complex procedure made the method expensive and not easy for use, however. To decrease the cost and simplify the procedure, we reduced the volume of the Dynabeads, added wash times, and skipped over the staining step so as to count the CD4 cells directly under an optical microscope. The CD4 count of 246 blood samples using our modified Dynabeads method (DynabeadsCD4) showed a significant correlation with that obtained by flow cytometry (FlowcytoCD4) (r = 0.91 [P < 0.0001]; slope = 1.03, intercept = -16). The sensitivity and specificity for a CD4 count less than 200 cells/microL were 79% and 94%, and for a CD4 count less than 350 cells/microL, the sensitivity and specificity were 95% and 88%, respectively. The positive and negative predictive values for a CD4 count less than 350 cells/microL were 97% and 83%, respectively. The systematic error was 8 cells/microL (95% confidence interval [CI]: 0.4-16). The cost of Dynabeads for 1 sample was less than $1.00; thus, the estimated cost per DynabeadsCD4 test is less than $3.00, including the cost of other disposable materials. Our modified method is simple, economic, and accurate enough to monitor antiretroviral therapy in resource-limited situations.  相似文献   
49.
Piglets infected in utero with porcine reproductive and respiratory syndrome virus (PRRSV) are born severely immunocompromised. In this article we more closely examine the effects of in utero PRRSV infection on circulating and thymic T cell populations. Numbers of CD4+, CD8+, and dual-positive lymphocytes were quantitated in circulation and in the thymus during the 2 weeks following birth. At birth we found that the number of circulating lymphocytes was suppressed by 60%. Lymphocyte numbers were also suppressed by 42% at day 7, but by day 14 the number of lymphocytes had rebounded and was actually 47% greater than controls. At birth and day 7, a drop in the number of CD4+ cells could partially explain the suppression we observed, while the rebound in total lymphocyte numbers seen at day 14 was due to a nearly fourfold increase in the number of circulating CD8+ cells. As a result, the normal CD4+:CD8+ ratio of between 1.4 and 2.2 for neonatal pigs was reduced to 0.1-0.5. The thymuses of infected piglets were found to be 50% smaller than those of control pigs and were characterized by cortical involution and severe cortical depletion of thymocytes. Analysis of the population of thymocytes revealed that double-positive thymocytes were suppressed to a greater degree than either single positive subpopulation. In addition, we show that the number of thymocytes undergoing apoptosis was increased twofold in piglets infected with PRRSV. Taken together, these results help explain the dramatic immunosuppression observed in neonatal animals infected in utero with PRRSV.  相似文献   
50.
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