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41.
钩吻对环磷酰胺化疗小鼠的造血保护作用   总被引:12,自引:2,他引:10  
用钩吻乙醇粗提物对小鼠肉瘤180(S180)生长抑制实验结果表明,其对S180无明显抑制作用,也未显示出能增强环磷酰胺(Cy)的抗瘤效应,但能明显减慢Cy化疗所致白细胞下降的速度和减轻白细胞降低的程度。提示钩吻对Cy化疗小鼠的造血功能具有保护作用。  相似文献   
42.
目的:探讨心肌缺血患者外周血白细胞计数及活性与心肌缺血发生发展的相关性。方法:对74例心肌缺血患者进行回顾性统计,以白细胞计数lO×109/L分组,大于此数患者归于异常组,小于此数则属于正常组.把心肌缺血患者分为两组.一组为心肌梗死组,另一组为心绞痛组,以健康体检者为对照组,分别就患者组与健康对照组在ld~3d/4d~6d/7d—lOd/lld—14d分四个阶段进行白细胞计数及活性测定。结果:心肌梗死组的白细胞计数明显高于冠心病组及正常对照组;随着病情的减轻白细胞计数逐渐下降,其白细胞活性与其记数呈正相关;且心肌梗死组白细胞教异常的病例数明显高于冠心病组及正常对照组。结论:白细胞数及活性的升高参与了心肌缺血的病理生理过程。  相似文献   
43.
老年人生理适应与防卫能力进行性下降,对有害因子易伤性增加,导致多种老年病的发生。因此,免疫系统功能与衰老的关系问题,已是现代老年病学和免疫学进行多方深入研究的重要内容。我们近两年多来对老年人免疫功能变化做了临床观察检测与统计分析。现报告如下。 1.临床资料  相似文献   
44.
The increased risk of coronary heart disease in cigarette smokersmay be due at least partly to an elevation of the leucocytecount Chronic passive smoking has also been found to be associatedwith an increased risk of coronary heart disease, but its effecton the leucocyte count has not been reported. In this study250 male factory employees aged 20–64 years were interviewedon smoking behaviour and exposure to environmental tobacco smoke,and blood counts were determined. Urinary cotinine was measureby radio-immunoassay and corrected for urinary creatinine concentrations.Mean leucocyte count was significantly higher among smokerscompared with non-smokers (8,666 compared to 6, 900; p<0.001).On the basis of smoking history, passive smokers had leucocytecounts similar to non-smokers. These findings were confirmedwhen leucocyte counts were compared with urine cotinine to creatinineratios. The association of haematocrlt and haemoglobin withsmoking was similar to that of leucocyte count These findingssuggest that any association of passive smoking with coronaryheart disease is not through an elevation of leucocyte count.  相似文献   
45.
观察雷公藤挥发油对小鼠免疫功能的影响,发现给药1周后,其可减少脾脏有核细胞数,减少 PFC 和 RFC 数目,抑制脾细胞对 ConA 诱导 T 细胞增殖的反应性,减轻DTH。这说明雷公藤挥发油对小鼠体液免疫和细胞免疫均有明显的抑制作用。  相似文献   
46.
Ethanol is a recognized immunosuppressive agent in the chronic alcoholic. However, the effects of ethanol exposure on the developing immune system have not been extensively investigated. This study evaluated the effects of early postnatal ethanol exposure, via breast milk, on splenic lymphocyte differentiation antigen expression in offspring reared by ethanol-fed mice. Maternal mice were fed a liquid diet containing 20% ethanol-derived calories during pregnancy (E-P), pregnancy and lactation (E-PL), or lactation (E-L). Ad libitumfed (C) and pair-fed (PF) control groups, fed a control liquid diet, were included. Expression of differentiation antigens on splenic lymphocytes from 21-day-old offspring reared by females in 1 of the 3 ethanol exposure conditions was evaluated by flow cytometry. Offspring reared by E-P females had similar numbers of splenic lymphocytes as offspring reared by C and pair-fed during pregnancy (PF-P) females. In contrast, offspring reared by E-PL and E-L females had fewer splenic lymphocytes than both PF-PL and PF-L (respectively), and C offspring. The number of Thy 1.2+, CD4+, CD8+, and IgG+ (B-cell) splenic lymphocytes was reduced in E-PL and E-L offspring compared with PF and C offspring. E-P offspring had fewer CD4+ and IgG+ splenic lymphocytes than C, but not PF-P, offspring. The percentage of Thy 1.2+ splenic lymphocytes was significantly reduced among E-PL and E-L offspring compared with PF-PL and PF-L (respectively), and C offspring. These results suggest that ethanol exposure of female mice during pregnancy, pregnancy and lactation, or lactation alone, alters the phenotypic development of splenic lymphocytes of offspring reared by these females. The greatest effect on differentiation antigen expression occurred when females consumed ethanol during the period of lactation. We speculate that direct exposure of the nursing offspring to ethanol via the breast milk was responsible for the reductions in specific splenic lymphocyte populations. These data demonstrate that mice reared by females fed ethanol during the early postnatal period have a marked depletion of each of the major subpopulations of splenic lymphocytes, and that Thy 1.2+ lymphocytes are differentially sensitive to ethanol.  相似文献   
47.
腹腔镜与开腹幽门环肌切开术的前瞻性比较研究   总被引:2,自引:0,他引:2  
目的研究比较腹腔镜幽门环肌切开术(LP)和开腹幽门环肌切开术(OP)治疗先天性幽门肥厚性狭窄的疗效及免疫功能的变化。方法自2003年4月-2006年7月将72例先天性幽门肥厚性狭窄患儿随机分成二组(LP组及OP组各36例),比较二组麻醉时间、手术时间、术后进食时间及术后并发症,监测二组术前、术后第一天、术后第三天的外周血T淋巴细胞亚群、C反应蛋白(CRP)及白细胞介素-6(IL-6)和肿瘤坏死因子(TNF)的变化并行对比研究。结果二组麻醉时间、手术时间、术后进食时间差异无统计学意义,OP组术后并发症要略多于LP组,比较二组术前、术后第一天、术后第三天的外周血T淋巴细胞亚群、CRP及IL-6和TNF的变化差异无统计学意义。结论腹腔镜幽门环肌切开术(LP)和开腹幽门环肌切开术(OP)治疗先天性幽门肥厚性狭窄的临床效果相近,二组患儿免疫功能的变化无显著性差异。腹腔镜幽门环肌切开术是一种稳定、可靠的手术,对于治疗先天性肥厚性幽门狭窄的效果满意。  相似文献   
48.
本文通过人精浆对PHA、ConA和PWM三种丝裂原诱导淋巴细胞转化反应的影响,间接了解HSP对T辅助、T抑制和B淋巴细胞功能的影响,结果发现不同浓度的精浆对三种丝裂原诱导的淋转反应均有明显抑制作用(P<0.05),且三种浓度HSP的抑制作用在无显著性差异(P>0.05);中浓度的精浆对PHA、ConA和PWM诱导转反应的抑制率分别为69.7、51.7和48.3%,说明精浆对机体的T辅助、T抑制性和B淋巴细胞功能均有明显的抑制作用。此外,还对精浆的免疫抑制作用机理和意义进行了讨论。  相似文献   
49.
目的 探讨轻度认知功能障碍(MCI)及阿尔茨海默病(AD)患者外周血淋巴细胞蛋白磷酸酯酶-2A(PP-2A)的变化.方法 用放射性配体结合试验检测11名健康对照者、11例MCI患者及11例AD患者外周血淋巴细胞PP-2A的活性,并用Western bolt检测PP-2A蛋白的表达.结果 MCI组外周血淋巴细胞PP-2A活性(0.71±0.12)及蛋白表达(0.80±0.05)与健康对照组[分别为(1.01±0.09)和(0.96±0.07)]相比明显降低(均P<0.01);AD组PP-2A活性(0.64±0.11)及蛋白表达(0.76±0.06)亦明显降低,与对照组相比差异有统计学意义(均P<0.01);AD组PP-2A活性及蛋白表达比MCI组有降低的趋势,但差异无统计学意义.结论 MCI及AD患者外周血淋巴细胞PP-2A的活性及表达降低,在MCI的诊断中可能有参考价值,同时亦可能对AD的诊断有一定的潜在的意义.  相似文献   
50.
Alcoholic patients often have impaired immune function, yet little is known about the precise mechanism(s) of this impairment. We have previously shown that ethanol consumption by mice alters copolymer-specific humoral and cellular immune responses. In this study, we asked whether alcohol consumption by mice would phenotypically alter lymphocyte populations. Female C57BL/6 mice were fed a nutritionally complete liquid diet containing 35% ethanol-derived calories for up to 8 days. As controls, mice either were fed a liquid control diet that isocalorically substitutes sucrose for ethanol or remained on a standard solid diet and water ad libitum. Although mice fed ethanol-containing liquid or pair-fed control liquid diets have decreased numbers of spleen cells compared with solid diet controls, only the ethanol-containing diet allowed normally nonresponder C57BL/6 spleen cells to make antibody responses to the poly(Glu50Tyr50) synthetic copolymer antigen. Flow cytometric analysis of splenic lymphocyte populations of mice on the ethanol-containing diet shows an increase in the relative proportion of T-lymphocytes as compared with mice on either solid or liquid control diets. No such change is seen for either B-cell or natural killer cell populations in these same mice. Both liquid control and liquid ethanol diets caused a slight decrease in the CD4:CD8 ratios of splenic T-lymphocytes. We see the relative percentage of T-cells bearing the αβ-cell receptor (TcR) increases in the spleens of liquid ethanol diet mice; a smaller increase TcRαβ usage is seen in the spleens of liquid control mice, compared with solid diet mice. Flow cytometric analysis shows that little, if any, difference exists in TcRγδ expression between the liquid ethanol and either the liquid control or solid diet groups. Preliminary analysis of TcRαβ subsets suggest that ethanol increases the percentage of T-cells expressing Vβ5 and Vβ8, and decreases the percentage of Vβ11 expressing cells. These findings suggest that, in addition to modifying the immune response, ethanol alters the phenotypic expression of lymphocyte subsets.  相似文献   
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