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Protein-calorie malnutrition (PCM) impairs immune responsiveness predisposing to Candida albicans sepsis, but mechanisms are unclear. This study examined the effect of PCM on enteric-derived C. albicans intestinal translocation and the ability of in vivo interferon-gamma (IFN-gamma) to upregulate macrophage (MO) candidacidal mechanisms in PCM mice. Control (24% casein) and low protein (2.5%) diets were given for 4 weeks. Mice (n = 160) were fed C. albicans in their drinking water for 3 days and C. albicans translocation (mean colony-forming units (CFU)/g tissue +/- SEM) to the GI tract, liver, spleen, and kidney was assessed at 1 and 5 days following endotoxin challenge of 1, 5, and 10 mg/kg body wt. In a separate study (n = 100 mice), IFN-gamma (1000-10,000 U/day ip) vs saline was given for 3 days prior to harvesting peritoneal macrophages for assay of superoxide anion (O2-), percentage macrophage phagocytosis of C. albicans, and percentage killing of C. albicans. On Day 1, fungal translocation to the intestinal wall and systemic organs in the PCM group was significantly higher. On Day 5, mean CFU were significantly higher in the PCM group, indicating impaired organ clearance. Mean O2-, phagocytosis, and killing were significantly impaired in the PCM group (P less than 0.05), but IFN-gamma improved all functions. PCM significantly depressed host responses to C. albicans. IFN-gamma treatment enhanced candidacidal mechanisms, suggesting a therapeutic role in the malnourished host predisposed to C. albicans sepsis. 相似文献
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王守炳 《四川生殖卫生学院学报》2004,(6):42-43,41
我国的彩票产业如今正处于高速发展的时期,15年来,全国累计发行的福利彩票和体育彩票约为500亿元人民币。笔者认为,发行文化彩票势在必行,不但可以丰富彩票市场的内容,也将给正处于资金短缺状况的公益文化事业募集资金,使彩票发挥更多的社会效益。 相似文献
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XGD-1对人外周血T淋巴细胞增殖和IL-2R表达的影响 总被引:1,自引:1,他引:0
目的 探讨XGD—l的免疫抑制作用及其作用机理。方法 不同浓度的XGD—l作用于植物血凝索(PHA)和刀豆索A(ConA)诱导的正常人外周血T淋巴细胞,共同培养48h和72h,用改良MTT法观察XGD—l对人T淋巴细胞增殖的影响,用流式细胞术检测XGD—l对T淋巴细胞表面IL—2R表达的影响;同时观察联合应用CsA和XGD—l对细胞增殖及IL—2R表达的影响。结果 XGD—l对PHA和ConA诱导的正常人外周血T淋巴细胞增殖有明显的抑制作用,其作用与药物浓度有关,在一定剂量范围内,抑制作用随XGD—l剂量的递增而加强;XGD—l对PHA和ConA激活的T淋巴细胞表面IL-2R的表达有显著抑制作用,阳性率从正常对照活化细胞的47.67%降为25.03%;联合应用CsA,上述抑制作用增强。结论 XGD-l具有免疫抑制作用,能降低IL-2R表达,可能是其免疫抑制作用的重要机理之一。 相似文献
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BACKGROUND: There are obvious advantages to increasing donor retention. However, for reasons of blood safety, certain donors may, in fact, be more desirable to retain than others. “Safe” donors are defined as those who provided a blood donation that was negative on all laboratory screening tests and who subsequently reported no behavioral risks in response to an anonymous survey. This study identifies the most important factors affecting the intention of “safe” donors to provide another donation. STUDY DESIGN AND METHODS: An anonymous survey asking about donation history, sexual history, injecting drug use, and recent donation experience was mailed to 50,162 randomly selected allogeneic donors (including directed donors) who gave blood from April through July or from October through December 1993 at one of the five United States blood centers participating in the Retrovirus Epidemiology Donor Study. Before mailing, questionnaires were coded to designate donors with nonreactive laboratory screening tests at their most recent donation. RESULTS: A total of 34,726 donors (69%) responded, with substantially higher response among repeat donors. According to reported intentions only, the vast majority of “safe” donors indicated a high likelihood of donating again within the next 12 months. Only 3.4 percent reported a low likelihood of donating again. A comparison of those likely to return and those unlikely to return reveals significant differences in demographics and in ratings of the donation experience. A higher proportion of those unlikely to return were first-time donors, minority-group donors, and donors with less education. The highest projected loss among “safe” donors was seen for those who gave a fair to poor assessment of their treatment by blood center staff or of their physical well-being during or after donating. CONCLUSION: These data suggest that efforts to improve donors' perceptions of their donation experience, as well as attention to the physical effects of blood donation, may aid in the retention of both repeat and first-time donors. 相似文献
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【目的】 了解缺氧缺血性脑损伤 (HIBD)早期脑细胞△Ψm的变化。 【方法】 7日龄新生大鼠随机分为正常对照组 (n =6) ,HIBD组 (n =3 6,分为HIBD后 0、1、2、3、4h时间点组 )。予以右颈总动脉分离结扎后再置8%O2 低氧舱 2 .5h ;断头处死后分离左右大脑半球制成单细胞悬液 ,加入终浓度为 1μmol的罗丹明 12 3于 3 7℃避光孵育 45min后 ,以流式细胞仪测定△Ψm并计算左右大脑半球△Ψm比值。 【结果】 正常P7SD大鼠左、右侧大脑半球脑细胞△Ψm分别为 ( 18.2 1± 1.2 6)MFL和 ( 18.93± 0 .74)MFL ,右∶左比值为 1.0 6。HIBD损伤使双侧大脑半球脑细胞△Ψm降低程度更明显 ,其中HIBD后 0h时△Ψm右∶左比值比正常时降低了 2 4.5 %(P <0 .0 5 )。HIBD后 1~ 3h时间内 ,△Ψm稍有回升。HIBD后 4h时HI损伤侧△Ψm值及右∶左比值均出现第二次降低现象 ,且程度更重 ,其中右 :左比值比正常时降低了 3 4%(P <0 .0 5 )。 【结论】 HIBD早期脑细胞△Ψm出现两次降低 (初次及二次降低 ) ,分别发生在HI损伤 0h和 4h时 ,提示有关改善线粒体功能的治疗尽量在△Ψm出现第二次降低前应用 相似文献
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