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61.
Effect of aging and caloric restriction on intestinal permeability.   总被引:2,自引:0,他引:2  
Intestinal permeability is increased in several disorders such as Crohn's disease or rheumatoid arthritis. Since aging leads to alteration of many biological functions, the effect of aging on intestinal permeability was studied by measuring the intestinal permeability in aging rats gavaged with different size permeability probes--mannitol, polyethylene glycol (PEG) 400, and inulin. In rats fed with control diet, there was a significant increase in intestinal permeability to medium size probes PEG 400 (14.8 +/- 0.4 and 21.0 +/- 1.1% at 3 and 28 months respectively, p less than .01) and mannitol (3.41 +/- 0.4 and 5.3 +/- 0.5% at 3 and 28 months, respectively, p less than .01). Intestinal permeability of the large macromolecule inulin did not change (0.42 +/- 0.03 and 0.38 +/- 0.02% at 3 and 28 months, respectively) with aging. There was no correlation between weight of the rats and their intestinal permeability. Because dietary caloric restriction has been found to prolong the life span, retard deterioration of several biological functions, and affect intestinal absorptive functions, we examined the effect of lifelong calorie restriction on intestinal permeability changes. Lifelong calorie-restricted diet did not affect age-related change in intestinal permeability. We conclude that intestinal permeability of medium size probes increases with aging and that lifelong caloric restriction does not prevent this change. We speculate that age-associated deterioration in intestinal barrier functions could permit increased systemic absorption of lumenal antigens and could perhaps contribute to the genesis of antigen-related age-associated diseases.  相似文献   
62.
Seventy-two patients of chronic obstructive pulmonary disease (COPD) of Qi deficiency syndrome with abnormal immune indices were treated with Yiqi Mianyi Granule (YQMYG) and the efficacy was compared with that of 30 cases treated with Zhenqi fuzheng Granule (ZQFZG) for control. Results showed that the markedly effective rate of symptomatic improvement of Qi deficiency in YQMYG group was 65.3%, the total effective rate 93.1%. 88.6% of the immune indices lower than normal were corrected and 43. 7% of them were normalized, while for indices that were higher than normal the rate were 78.2% and 52.9% respectively. These results suggested that YQMYG could improve symptom of Qi Deficiency markedly, strengthen cellular immunity and regulate immune dysfunction. Its therapeutic efficacy was obviously superior to ZQFZG (P<0.Q5).  相似文献   
63.
B超诊断腰椎间盘突出症的临床价值(附64例分析)   总被引:1,自引:0,他引:1  
报告经CT检查和临床治疗证实的64倒腰椎间盘突出症的B超检查结果,B超检出70个突出之椎间盘,CT检出73个,阳性率之比为70/73。70个突出椎间盘中,中央型5个,偏中央型20个,后外侧型44个,极外侧型1个;轻度30个,中度28个,重度12个。分型分度与临床表现及治疗选择有密切关系。B超检查与CT相此较,具有近似的诊断价值,但经济、实用,操作简单方便,值得推广。  相似文献   
64.
庚酸睾酮男性抗生育作用的临床研究   总被引:1,自引:0,他引:1  
62名健康男性,自愿接受每周1次200mg庚酸睾酮(TE)肌肉注射的避孕方法研究。4人非医学原因中断试验,其余受试者先后实现无精子,自第1次注射TE到全部达到无精子的平均时间为108(58~232)天,在此后的连续12个月共592个妇女月避孕效果观察中,有1例怀孕,临床避孕率为98%(Pearl指数为2.02/100妇女年)。停药后,平均188(135~254)天全部受试者的精子密度恢复到用药前水平或高于20×10~6/ml。在用药期间,除预料的血清睾酮升高、促性腺激素(FSH、LH)受抑制、睾丸体积缩小、体重和血红蛋白轻度增加以及2例出现轻度痤疮外,其余检查,包括血脂代谢、肝肾功能、前列腺大小、血压和性功能等均无显著性改变。结果表明,由TE抑制生精作用的男性激素避孕方法具有效果好,可逆和毒副作用小的优点。  相似文献   
65.
Implantation of porcine bone morphogenetic protein (pBMP) in the muscle induces differentiation of mesenchymal-type cells and results in endochondral bone formation. pBMP was isolated from porcine demineralized bone matrix and purified by hydroxyapatite chromatography, Sephadex G75 gel filtration, preparative sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), preparative isoelectric focusing (IEF), and chromatofocusing fast protein liquid chromatography (FPLC). Porcine BMP has an MW of 26 K and a range of pI from 4.65 to 4.73 determined by SDS-PAGE and IEF, respectively. Reconstitution with the citrate buffer supernatant fraction enables as little as 50 micrograms of the soluble pBMP fractions to induce osteogenesis in an in vivo assay. Chemical modification studies indicate that the osteoinductive potential of the pBMP molecule depends on tyrosine, carboxyl groups, and disulfide bonds and can be increased by modification of sulfhydryl groups. Modification of arginine and tryptophan has no effect on bioactivity. By pepsin-limited proteolysis, fragments of pBMP with an MW of 6-14 K show definite, although reduced, BMP activity.  相似文献   
66.
作者选择乙基纤维素、聚乙烯醇等高分子材料制成涂膜剂,用大鼠皮进行双氯灭痛药膜的体外透皮速率测定。结果表明,氮酮与丙二醇可以促进药物渗透。不同的高分子材料可影响药物的扩散与释放,从而影响其透皮速率。与无膜无促透剂处方相比,药物在乙基纤维素中的透皮速率没有增加,在聚乙烯醇膜中的透皮速率有显著增加。  相似文献   
67.
There is a relationship between viral infection and aggravation of bronchial asthma symptoms. Viruses belong to the strongest and fast acting inducers of interferon (IFN), which, in turn, may enhance histamine release from effector cells. We have administered IFN intrabronchially to 49 patients suffering from bronchial asthma. The impairment of lung ventilation with significant decrease of forced expiratory volume in one second (FEV1) have been observed in majority of the patients who inhaled crude or purified IFN preparations.  相似文献   
68.
选择南方热区某特种部队战士52人,分两组分别口服5mgVitB1和VitB2,收集4h尿液,用荧光法进行负荷试验。结果:VitB1组,所测29人中,15人缺乏,9人不足,2人正常,3人充裕;VitB2组,所测23人中,11人缺乏,12人不足,反映该部队全年约5%的发病是由于VitB1、VitB2缺乏不足所致。其原因为膳食摄入不够  相似文献   
69.
报告应用微粒皮肤移植技术抢救成功7例特大面积烧伤病人。文中介绍了手术方法、注意事项,指出了本术式的优缺点,并对该领域国内外的发展状况,作了简单叙述。  相似文献   
70.
Endothelial dysfunction, as evidenced by decreased stimulated release of endothelium-derived relaxing factor (EDRF), occurs after reperfusion of the ischemic myocardium. To better understand this endothelial dysfunction, isolated cat hearts were perfused under constant flow by the Langendorff procedure with Krebs-Henseleit solution devoid of blood cells. Following global ischemia (90 minutes) and reperfusion (20 minutes), coronary vasorelaxation to the endothelium-dependent vasodilator acetylcholine (ACh) was 70 +/- 3% of initial values (p less than 0.01) compared with 90 +/- 4% in nonischemic control perfused hearts. No decrement occurred in response to the endothelium-independent vasodilator nitroglycerin (NTG). Coronary artery rings isolated from the ischemic left circumflex coronary artery showed a similar degree of endothelial dysfunction to ACh, with normal relaxation in response to NaNO2. Autologous cat neutrophils (100 million cells), activated with 100 nmol/L f-met-leu-phe infused into the heart directly before and throughout reperfusion, resulted in a further decrement in ACh-induced vasodilation, to 55 +/- 5% of initial response, with no effect on NTG-induced vasodilation. Similar results were obtained with coronary artery rings isolated from perfused cat hearts and exposed to neutrophils. This neutrophil-enhanced endothelial dysfunction was inhibited by human superoxide dismutase as well as by an antibody to the adherence glycoprotein complex CD-18 (i.e., MAbR 15.7). Therefore endothelial dysfunction occurs initially upon reperfusion of the previously ischemic heart and is aggravated by superoxide radicals produced by activated neutrophils.  相似文献   
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