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91.
Enhancing and suppressive effects of tumour necrosis factor/cachectin on growth of Trypanosoma musculi 总被引:3,自引:2,他引:1
The effect of human recombinant TNF on the growth of T. musculi has been investigated. When added to parasites cultured in vitro, TNF inhibited their growth. In the presence of thioglycollate-elicited peritoneal exudate cells, the opposite effect was seen and TNF enhanced the growth of trypanosomes in vitro. Similarly, administration of TNF in vivo during the course of infection led to a net increase in the parasite population. It is suggested that TNF exerts a direct antitrypanosomal effect while simultaneously promoting the growth of the parasite through an indirect effect mediated via the host's cells, possibly the macrophages. 相似文献
92.
尿流式细胞学在诊断移植肾急性排斥反应中的应用价值 总被引:1,自引:0,他引:1
目的:探讨尿流式细胞学在诊断移植肾急性排斥反应中的临床应用价值。方法:对43例肾移植受者的116份尿样本进行尿流式细胞学分析,并将急性排斥组和肾功能稳定组的分析结果进行比较。结果:急性排斥反应组尿淋巴细胞总数以及HLA-DR^ 淋巴细胞数显著增多,与肾功能稳定组比较,P<0.01,CD8^ 细胞亦增多(P<0.05),而CD3^ ,CD4^ ,CD19^ 细胞数变化两组差异不显著(P>0.05),在诊断移植肾急性排斥反应上,HLA-DR阳性样本和淋巴细胞数阳性样本的诊断敏感性和特异性分别达95.2%,90.5%,和92.6%,87.4%,结论:尿流式细胞学分析可反映移植肾内的免疫状态,尿淋巴细胞数的显著增多和尿HLA-DR^ 淋巴细胞增多可以作为诊断急性排斥反应的有意义指标。 相似文献
93.
Stuart Sherman MD Nancy S. Nieland MD David H. Van Thiel MD 《Digestive diseases and sciences》1988,33(3):368-374
Summary An unusual case of a woman with primary biliary cirrhosis and cutaneous sarcoidosis is described. The factors that allow a specific diagnosis of each condition are presented and the literature pertaining to such complex and unusual cases is presented.This work was supported in part by a grant from the Gastroenterology Medical Research Foundation of Southwestern Pennsylvania. 相似文献
94.
目的:研究DIFF33H在人T淋巴细胞白血病细胞Jurkat凋亡中的表达规律及其生物学功能。方法:采用PCR扩增DIFF33H cDNA,Northern blot分析DIFF33H的mRNA表达,MTT法测定细胞凋亡。结果:在重组可溶性TRAIL诱导的人T淋巴细胞白血病细胞Jurkat凋亡过程中,DIFF33H mRNA的表达水平随着Jurkat细胞的凋亡而下降,并对重组可溶性TRAIL的作用具有浓度和时间的依赖性。在抗肿瘤药物5-FU诱导肿瘤细胞凋亡过程中,DIFF33H的mRNA表达水平也显著下降。结论:DIFF33H参与人T淋巴细胞白血病细胞Jurkat凋亡的调控。 相似文献
95.
Rui T Marinho Ruth M Pinto Maria L Santos Miguel Carneiro de Moura 《Liver international》2004,24(5):413-418
BACKGROUND: Seroreversion, negativation of anti-hepatitis C virus previously positive, is sometimes found in some chronic hepatitis C-sustained responders (SRs) to antiviral therapy. AIMS: To determine the probability of seroreversion in SR treatment with Interferon and Ribavirin, and lymphocyte T helper (CD4+) reactivity to HCV antigens. METHODS: Thirty SR were followed on average for 54.8 months. Anti-HCV was tested by third generation test. Peripheral blood mononuclear cells (PBMCs) were isolated from venous blood and cultured to evaluate CD4+ proliferation in response to 2 microg/ml of eight HCV recombinant antigens from core, NS3, NS4, NS5 regions. RESULTS: Seroreversion was verified in 23% of patients (7/30), appearing at 47.5+/-24.0 months. The probability of anti-HCV loss in this group was 25% at 56 months after ending therapy. In 57% (4/7), anti-HCV returned to positive. These 7 SR patients with seroreversion also showed weaker CD4+ reactivity in 5% of tests (3/56) than the remaining 23 anti-HCV-positive SRs who showed stronger reactivity in 18% of tests (33/184), P=0.036. CONCLUSIONS: One-quarter of the SR showed seroreversion of anti-HCV and weaker CD4+ specific HCV proliferation than those who remained anti-HCV positive. The data suggest that complete viral eradication is a possible and achievable clinical objective. 相似文献
96.
W D Foltz Y Yang J J Graham J S Detsky G A Wright A J Dick 《Magnetic resonance in medicine》2006,56(6):1311-1319
MRI evaluations of intramyocardial hemorrhage in acute infarction have relied on T(2) and T(2)(*) shortening only. We propose a more comprehensive evaluation of hemorrhagic infarction based on the concept that fluctuations in T(2) and T(1) relaxation in acute reperfused infarction will reflect transient edema and hemoglobin oxidative denaturation to uncompartmentalized methemoglobin. Anteroapical infarction was created via percutaneous balloon in young swine (22-25 kg, N = 12). T(2), T(1), diastolic wall thickness (DWT), and the Gd-DTPA partition coefficient (lambda) were measured on days 0, 2, and 7. DWT was elevated at 1 hr postreperfusion (128% +/- 53%, P = 0.0001), and alleviated on days 2 and 7 (48% +/- 10%, P = 0.008; 53% +/- 24%, P = 0.003). T(2) and T(1) elevations were coincident with early edema (DeltaT(2) = 55% +/- 24%, P < 0.0001; DeltaT(1) = 27% +/- 18%, P < 0.04). T(2) and T(1) were nearly normal on day 2 (DeltaT(2) = 8% +/- 8%, P = 0.27; DeltaT(1) = 0% +/- 1%, P = 0.65). On day 7, T(2) increased while T(1) decreased (DeltaT(2) = 27% +/- 16%, P = 0.005; DeltaT(1) = -14% +/- 10%, P = 0.02). Lambda was elevated by >150% at all time points (P < or = 0.002). Histology verified hemorrhagic injury. T(1) and T(2) fluctuations are consistent with transient edema, as well as hemoglobin oxidative denaturation to decompartmentalized methemoglobin. This methodological development may broaden our understanding of hemorrhagic microvascular injury and improve its detection in clinical populations. 相似文献
97.
为筛选大叶紫薇叶中具有降血糖活性的成分,采用3T3-L1细胞葡萄糖消耗模型作为检测手段,对大叶紫薇叶提取物采用HP-20树脂吸附、溶剂萃取、制备薄层分离和制备高效液相分离,导向筛选具有降血糖作用的各分离组分.结果发现,大叶紫薇叶中corosolic acid、熊果酸和总三萜具有降血糖活性. 相似文献
98.
目的探讨经门静脉注射药物治疗慢性乙型肝炎的可行性,观察门静脉置管注射中西药对慢性乙型肝炎患者细胞免疫功能的影响。方法8例肝癌术后的慢性乙型肝炎患者,于肝癌手术时皮下埋置药盒门静脉内置管,向药盒内注入胸腺肽40mg,黄芪注射液10ml。治疗前后用流式细胞术绝对计数T淋巴细胞及其亚群、自然杀伤细胞(NK),并观察其副反应。结果治疗前后CD3665.63±434.80个/μlvs1326.50±551.09个/μl,CD3 CD8 275.63±205.78个/μlvs513.50±231.00个/μl,CD3 CD4 515.88±329.75个/μlvs981.75±478.54个/μl,NK细胞130.86±176.58个/μlvs303.43±190.90个/μl,差异具有显著性意义(P<0.05),除1例中度发热、4例轻度发热外,无其他副反应。结论胸腺肽与黄芪合用可增强慢性乙肝患者的细胞免疫功能。经门脉注射药物可能成为乙肝治疗的新途径,应加大样本进一步研究。 相似文献
99.
Summary: Oral administration of carbamazepine (CBZ)(15, 10, or 5 mg/kg) to mice significantly decreased both humoral and cellular immune responses evaluated by enumeration of direct and indirect plaque-forming spleen cells (PFC) and delayed–type hypersensitivity reaction (DTH) against sheep red blood cells (SRBC) as compared with those observed in normal control animals. Moreover, spleen T cells obtained from CBZ–treated donor mice were capable of decreasing both PFC and DTH responses of normal spleen cells transferred into lethally irradiated recipient animals. The immunodepressor effect of CBZ was observed even though administration of CBZ induced augmentation of spleen cellularity. 相似文献
100.
Clonal deletion and anergy are two major mechanisms of self-tolerance. However, the molecular mechanisms underlying clonal deletion and anergy, as well as the threshold of TCR affinity/avidity required for these processes, are not known. Expression of the V beta 8.1 TCR correlates with the reactivity of the T cells to the minor lymphocyte stimulating locus-1a (Mls-1a) and T cells expressing this TCR are deleted in the thymus of Mls-1a mice. Similarly, in TCR V beta 8.1 transgenic mice, the number of CD4+CD8-T cells is reduced in Mls-1a mice. However, small numbers of CD4+CD8-T cells remain in the periphery of adult Mls-1a transgenic mice. We have generated T cell clones from TCR V beta 8.1 transgenic mice by stimulation of lymph node T cells with C57BL/6 alloantigens. Interestingly, CD4+CD8-V beta 8.1+ clones isolated from the transgenic mice of Mls-1a background responded to the self-antigen Mls-1a, to which they did not respond in primary assay. Reactive patterns of the clones were compared with clones derived from Mls-1b mice. Proliferation and cytokine production of the clones from Mls-1a mice to the self-antigen Mls-1a were generally reduced when compared with clones from Mls-1b mice. More importantly, T cell clones from Mls-1a mice required more Mls-1a antigen for their activation, and were more susceptible to the inhibitory effects of anti-CD4 antibody on the proliferative responses to Mls-1a than those from Mls-1b mice. These results suggest that the T cell receptor on clones derived from Mls-1a mice have functional but reduced affinity/avidity for self-antigen Mls-1a. 相似文献