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21.
对1例巨大甲状腺肿瘤患者在体外膜肺氧合辅助下行肿瘤切除术,手术顺利,历时12.0h,切除肿瘤500g,住院23d患者康复出院。提出术前充分评估患者状况、做好心理护理和器械物品准备,术中熟悉体外膜肺氧合的操作方法、积极配合手术、密切观察病情等,是获得良好手术效果的重要环节。  相似文献   
22.
目的探讨术中实时超声导航在脑动静脉畸形(AVM)外科治疗中的应用价值。方法26例脑AVM显微手术切除术中,使用Aloka SSD 4000型超声检查仪扫描,进行AVM定位、辨别供血动脉和引流静脉;确定血肿与AVM的关系以及血流动力学监测。病变切除后重复超声检查AVM残留与否,并与术后脑血管造影结果对比。结果26例畸形血管团均住实时超声下清晰显示并获得全切除。血肿区为高同声无血流信号;供血动脉与正常血管在血流动力学上有差别;术中超声影像所示的病变全切除为术后血管造影所证实。结论术中实时超声能够对脑AVM进行准确定位,指导皮质切口的设计,并可判定病灶是否全切除.对于术前的MRI、DSA检查起到很有价值的补充作用。  相似文献   
23.
Cytogenetic abnormalities are rarely found in patients with juvenile chronic myelogenous leukemia (JCML). In patients with chromosomal abnormalities, chromosomes 7 and 8 are usually involved. A case of JCML with 47 XXX and a 46 XX karyotype is described and the literature is reviewed. To our knowledge, this is the first case ever to have been reported.  相似文献   
24.
目的为了解旁道位置与室上性心动过速初次发作时年龄及性别的关系.方法对128例已进行过射频消融的患者进行了回顾性分析.结果男性左侧旁道发病时平均年龄大于右侧及中隔旁道平均为14岁和9岁;大于女性左侧旁道7岁,男性显性旁道发病时平均年龄小于隐匿性旁道7岁.而女性显性旁道与隐匿性旁道、左侧旁道与右侧旁道发病时平均年龄无显著性差异.结论旁道位置与室上速初次发作时年龄及性别有关.  相似文献   
25.
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   
26.
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   
27.
BACKGROUND: Developments in accelerator mass spectrometry (AMS) now permit the determination of femtogram amounts of 26Al in blood and in various tissues with good precision and free of external contamination. METHODS: In the present study we used trace quantities of 26Al to investigate the intestinal absorption and compartmentalization of aluminium in rats with renal failure (Nx, 5/6 nephrectomy) and in pair- fed controls (C). Single oral doses of 20 ng 26Al were administered to six animals in each group and, subsequently, 24-h post-load 26Al was analysed in serum, urine, bone, liver, and spleen by means of AMS. RESULTS: Serum concentrations of 26Al were significantly lower in uraemic rats compared to controls, whereas urinary excretion was comparable (Nx, 7.11 +/- 5.78 pg/day vs C, 9.46 +/- 6.10 pg/day), suggesting a higher fraction of ultrafiltrable serum 26Al in uraemia. The target tissues of cellular transferrin-mediated 26Al uptake, liver and spleen, tended to show a larger degree of aluminium accumulation in controls (0.26 +/- 0.31 pg/g vs Nx, 0.14 +/- 0.10 pg/g and 0.37 +/- 0.27 pg/g vs Nx, 0.25 +/- 0.27 pg/g respectively). In contrast, in bone, a site of extracellular aluminium deposition, 26Al concentrations were more elevated in uraemia (1.22 +/- 0.59 pg/g vs C: 0.68 +/- 0.30 pg/g). Estimated total 26Al accumulation in all measured target tissues was significantly higher in uraemic rats (28.15 +/- 9.90 pg vs C: 17.03 +/- 7.03 pg) and total recovery of 26Al from tissue and urine was 26.58 +/- 6.74 pg in controls and 35.75 +/- 7.03 pg in uraemic animals, suggesting a fractional absorption of 0.133% and 0.175% respectively. CONCLUSIONS: Our data suggest that fractional absorption from a dietary level dose of 26Al is about 0.13%. Compartmentalization occurs in transferrin-dependent target tissues such as liver and spleen; however, in quantitative terms extracellular deposition in bone is more important. Uraemia has a significant effect on the intestinal absorption and compartmentalization of aluminium. It enhances fractional absorption and increases subsequent extracellular deposition of aluminium in bone. However, at the same time uraemia does not increase transferrin-dependent cellular accumulation of aluminium in liver and spleen.   相似文献   
28.
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   
29.
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   
30.
报道福建某盐场从事日晒海盐生产人工机体内高镁对心血管系统的影响,通过现场空气、饮水、主良的镁含量测定,并对进入机体途径进行分析,得出空气、卤水接触、饮水为机体镁增高的主要来源。不同对象头发镁含量测定结果显示,以接触卤水、劳动强度大的盐工最高,并随机体内镁含量增高,出现血压偏低、心率减慢、心电图P-R间期延长、QRS波增宽、T波高尖等机体高镁反应,与临床高镁血症相似。  相似文献   
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