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41.
The level of tetanus antibody was determined with the passive hemagglutination method in 503 sera of 10 to 90-year-old persons. Immunity to tetanus was age-dependent: the percentage of immune persons amounted to 90% –100% in persons below 40 years and then declined to 70% and 60% in persons in the 40 – 50 and above 50 year-old groups, respectively. Males above 30 years are better immunized than females. The comparison of the results of the present study with results of several periodic surveys performed in the last 27 years showed gradually increasing immunity level in all age groups. The findings are in agreement with age-dependent incidence of tetanus, which has become now, in Poland, a disease primarily of older people.  相似文献   
42.
环缩酚肽抑制视网膜表达VEGF及PECAM基因和血管增生   总被引:2,自引:0,他引:2  
[目的]观察两种环缩酚肽衍生物(Hep-A和Hep-B)对氧诱导的小鼠视网膜表达血管内皮生长因子(VEGF)和细胞黏附分子(PECAM;ICAM-1;VCAM-1)基因的影响及血管增生的变化.[方法]建立氧诱导的血管增殖性视网膜病变模型,12 d开始给小鼠皮下注安慰剂(第1组,n=7)、Hep-A 10 mg/kg(第2组,n=6)或者Hep-B 10 mg/kg(第3组,n=6),每天两次.5 d后取出左侧眼,分离视网膜并抽提RNA,用荧光定量PCR测出上述基因含量,并分别求出每个靶基因与标准基因S16含量的比率;右眼经心脏荧光素灌注后取眼球做视网膜平铺片,用图像分析软件定量计算视网膜新生血管的面积.[结果]视网膜中VEGF/S16的mRNA比率为:第1组(0.554±0.050),第2组(0.355±0.037),第3组(0.287±0.051);PECAM/S16为:第1组(2.050±0.249),第2组(1.228±0.153),第3组(1.027±0.210).经ANOVA分析,第2组和第3组分别与第1组比较,视网膜中VEGF基因表达分别减少36%和48.2%(P=0.001);PECAM基因表达分别减少40.1%(P<0.05)和49.9%(P<0.01);而VCAM-1和ICAM-1表达无明显差异.视网膜平片检测视网膜新生血管面积:第1组为(1.06±0.03)mm2/眼,第2组为(0.17±0.01)mm2/眼,第3组为(0.11±0.01)mm2/眼;经ANOVA分析,第2组和第3组分别与第1组比较,视网膜新生血管的面积明显减少(P<0.001).[结论]两种环缩酚肽衍生物均抑制氧诱导的小鼠视网膜表达VEGF和PECAM基因,并抑制其形成视网膜新生血管.  相似文献   
43.
Due to the shortage of human organs, xenotransplantation is being explored as an alternative to allotransplantation, but immune rejection remains a major hurdle to its implementation. We tested the ability of human CD4+CD25+ T cells (Treg cells) to suppress CD4+ T cell-mediated anti-porcine xenoresponses usingin vitroassays. Human Treg cells were hyporesponsive to porcine cell stimulation and suppressed the proliferative response of CD4+CD25- T cells in a dose-dependent manner, and comparison of the allo- and xenoresponses indicated that more Treg cells might be required to suppress the xenogeneic response than the allogeneic response. Stimulation of CD4+CD25- T cells with porcine cells resulted in secretion of IFN-gamma, TNF-alpha, IL-10, IL-6 and IL-2, and Treg cells suppressed the secretion of these cytokines, as well as the CD4+CD25- T-cell cytolytic response against porcine cells. These results suggest a potential role for Treg cells in promoting xenograft survival.  相似文献   
44.
回收式自体输血对手术患者凝血及免疫功能的影响   总被引:8,自引:0,他引:8  
目的探讨回收式自体输血(BS)对机体凝血状态和T淋巴细胞亚群、NK细胞功能的影响。方法选择骨科大手术患者40例,随机分为自体输血组(BS组)和异体输血组(异体组)各20例,术中分别采用BS及输异体血,分别于术前、输血后1h及输血后24h测定血常规、APTT、PT、FIB及ACT;流式细胞仪测定输血后第1天、第5天T淋巴细胞亚群CD3^+、CD4^+、CD8^+、CD4^+/CD8^+值及NK细胞。结果输血后1h两组APTT、PT、ACT均延长,FIB和PLT计数均降低(P〈0.05),但尚在正常范围内,组间比较元显著性差异(P〉0.05)。异体输血组输血后第1天和第5天CD3^+、CD4^+、CD8^+、NK变化显著低于BS组(P〈0.01);BS前后上述指标元明显变化(P〉0.05)。结论.BS对凝血功能的影响与异体输血相似,大量回输时应注意补充凝血因子和血小板;BS对机体细胞免疫功能元明显抑制作用。  相似文献   
45.
目的 探讨常年性变应性鼻炎 (PAR)患者细胞免疫功能状态及微波凝固治疗的作用机制。方法 观察组 2 5例PAR患者分别于微波治疗前以及治疗 1个月后应用免疫组化法检测鼻粘膜上皮和外周血CD3、CD4、CD8、CD4/CD8水平。健康对照组 1 5例亦作相应检测。结果 PAR患者治疗前鼻粘膜及外周血CD3、CD4明显高于正常人 ,CD8低于正常人 ,CD4/CD8比值升高 ,与正常人比较差异有显著性 (P <0 .0 5)。微波治疗后CD4明显减少 ,CD8升高 ,CD4/CD8接近于健康对照组。结论 PAR患者存在明显的细胞免疫功能障碍 ;微波局部凝固治疗可改善PAR患者的细胞免疫状况。  相似文献   
46.
观察保肾口服液对IgA肾病小鼠T细胞^3H-TdR掺入及其分泌IL-2水平的影响,结果表明低、中、高3种浓度的保肾口服液均能显著促进IgA肾病小鼠的自发性和ConA刺激的T细胞^3H-TdR掺入,促进T细胞合成,分泌IL-2,提前给药作用相同。提示保肾口服液有显著增强IgA肾病小鼠细胞免疫功能的作用。  相似文献   
47.
The roles of IgE and mast cells on expulsion of adult Hymenolepis nana from the intestine were examined in mice. IgE-dependency was determined by comparing congenitally IgE-deficient SJA/9 and IgE-producing SJL/J mice infected with 50 H. nana eggs. Anti-H. nana IgE antibody was detected at three weeks post infection (p.i.) in SJL but not in SJA mice. The number of adult worms in the intestines of SJA and of SJL mice were similar at two weeks, but significantly more were found in SJA mice at three weeks p.i. Treatment of mice with anti-ɛ antibody also resulted in an increased worm burden at three weeks, suggesting participation of IgE in expulsion of H. nana. Intestinal mastocytosis was induced by infection regardless of the IgE status of the mice. Mast cell-dependency was tested in mast cell-deficient W/Wu and in normal littermate +/+ mice infected with 100 H. nana eggs. Anti-H. nana antibody was detected in both groups of mice at three weeks p.i. Worm expulsion seemed to be mast cell dependent because expulsion was less complete in W/Wu mice at three weeks p.i. Peripheral blood eosinophilia was comparable at three weeks p.i. in both IgE and mast cell sufficient and deficient mice. These results suggest that IgE and mast cells participate in the expulsion of H. nana adults from intestine in mice.  相似文献   
48.
细脚拟青霉对大鼠血液蛋白质水平及其生长的影响   总被引:3,自引:0,他引:3  
用10%细脚拟青霉水煎剂1.0ml·d(-1)给大鼠灌胃,连续21d,对ip环磷酰胺(20mg·kg(-1)×7d)所致免疫抑制大鼠血液中血红蛋白、血清总蛋白、球蛋白水平下降及体重减轻等均有显著的保护和逆转作用;对正常大鼠血液中血红蛋白水平也有显著提高。提示:细脚拟青霉可改善机体的营养状况,促进生长,逆转免疫抑制作用。  相似文献   
49.
A deficiency of total energy or of one or more essential nutrients, including vitamins A, B6, B12, C, and E, folic acid, zinc, iron, copper, selenium, essential amino acids and essential fatty acids, will impair immune function and increase susceptibility of the host to infectious pathogens. This is most likely because these nutrients are involved in the molecular and cellular responses to challenge of the immune system. Providing these nutrients to deficient individuals restores immune function and improves resistance to infection. Thus, appropriate nutrition is required in order for the host to maintain adequate immune defences towards bacteria, viruses, fungi, parasites and tumour celîs. Although the intakes of several nutrients which result in greatest enhancement of immune function appear to be greater than recommended intakes, excess intake of certain nutrients also impairs immune responses. Some nutrients (e.g. glutamine, arginine) may become limiting in critical illness and there is mounting evidence that provision of these will aid patient recovery.  相似文献   
50.
Bacterial and fungal peritonitis is associated with a high riskof morbidity and mortality in patients undergoing continuousambulatory peritoneal dialysis (CAPD). Impaired cellular hostdefence in the peritoneal cavity underlies this risk. Two granulocyteinhibitory proteins with a molecular weight of 28000 dalton(GIP I) and about 9500 dalton (GIP II) with homology to light-chainproteins and beta respectively, were isolated from peritonealdialysis effluents. In vitro, both granulocyte inhibitory proteinsinhibit PMNL glucose uptake, phagocytosis and intracellularkilling of bacteria. The IC50 of GIP I or GIP II required forinhibition of half-maximal FMLP-induced or PMA-stimulated PMNLfunction was found to be in the nanomolar range, suggestingvery specific inhibition. These data may explain, at least inpart, defective local cellular host defence in CAPD patients.  相似文献   
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