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131.
AIM: To determinate the percentage change on natural killer(NK) subsets of peripheral blood and decidua in between normal early pregnancy and spontaneous abortion. METHODS: Flow cytometry was used to detect the expression of CD56 and CD16 on lymphocytes of decidua and peripheral blood in normal early pregnancy and spontaneous abortion. RESULTS: In peripheral blood, the percentage of CD56+ of spontaneous abortion tended to decrease in comparison with normal early pregnancy, and the percentage of CD56+CD16+ in spontaneous abortion was significantly less than that in normal early pregnancy. The percentages of different natural killer subsets in decidua of spontaneous abortion were significantly lower than those in decidua of normal early pregnancy. CONCLUSION: The decrease of CD56+NK cells in decidua may be one of causes for abortion, the loss of CD56+ and CD56+CD16+NKcells in peripheral blood could have a diagnostic value for spontaneous abortion. 相似文献
132.
AIM:To detect the expression of hHR21spgene in normal human peripheral blood cells and in hemapoietic cell from fanconi anemia(FA) patients bone marrow after exposure to UV and gamma-irradiation.METHODS:RNA of FA hemapoietic cell and normal peripheral blood cells were harvested after UV and gamma irradiation. hHR21sp gene expression was analyzed using RT-PCR, southern blot hybridization, phosphoimmage autoradiogram.RESULTS:The expression of hHR21sp gene in PBL varied with the time of UV gamma-irradiation and increased obviously six hours after 80 J/M2 UV-or 5 Gy gamma-irradiation. However, the expression was down-regulated in FA hemapoietic cell from FA patients indicating that hHR21sp expression is something related to the ability of cells to repair DNA double strand break.CONCLUSION:The expression of hHR21sp down-regulated in the FA syndrome and this might be involved in the pathogenesis of the FA. 相似文献
133.
WANG Hui-yan ZHANG Xiang-hong YAN Xia WANG Jun-ling SUN Xu-ming YANG Yong-bin WANG Feng-rong 《园艺学报》2001,17(2):131-133
AIM: To explore the effects of aflatoxin G1(AFG1 )on proliferation and TNF-α secretion of human peripheral blood mononuclear cells(HPBM) in vitro. METHODS: The effects of AFG1 on proliferation of HPBM were analysed with flow cytometric (FCM) DNA analysis and MTT bioassay, while that on TNF-α secretion was detected with ELISA.RESULTS: FCM analysis revealed that 6 h after treatment, proliferation index(PI) of 1000 μg/L AFG1 treated HPBM was significantly higher than that of control. 24 h after AFG1 treatment, stimulating effects on proliferation was found in HPBM treated with AFG1 at 200 μg/L and 1 000μg/L.Regression analysis showed that PI was postively correlated with the concentrations of AFG1 in the concentration range from 0 to 1 000μg/L( r=0. 5122 and 0.5119 respectively,P<0.05).MTT bioassay showed that the A value of the cells treated with AFG1 at 2 000 μg/L was higher than that of the control. Double antibody sandwich enzyme linked immunosorbent assay (ELISA) results showed that AFG1 at a dose of 100 μg/L could significantly inhibit lipopolysaccharide-induced TNF-α secretion.CONCLUSION: AFG1 could stimulate the proliferation of HPBM and could decrease TNF-α secretion at certain concentration. 相似文献
134.
AIM: To study the pathological relationship of vascular cell adhesion molecule-1 (VCAM-1) expression and monocyte/macrophage infiltration with focal brain ischemia. METHODS: Immunohistochemical technique and focal brain ischemia/reperfusion model were used in the study in order to explore profiles and time-course of VCAM-1 expression and monocyte macrophage (ED2 positive cell) infiltration in ischemic rat brain. RESULTS: VCAM-1 was up-regulated in microvascular endothelial cells in ischemic cortex at 1h postischemia, and continuously expressed during the time of reperfusion. ED2 positive cells infiltrated into ischemic cortex at 1h iscehmia/ 2h reperfusion and then ED2 positive cells increased gradually with the time of reperfusion, ED2 positive cell infiltration showed apparently relationship with VCAM-1 expression, and both of them exhibited the some changes of time-dependence. CONCLUSION: Cerebral ischemia induced VCAM-1 expression and ED2 positive cell infiltration and VCAM-1 may regulate the recruitment of ED2 positive cells in the ischemic brain region. The results suggested that VCAM-1 and ED2 positive cells may be participated in the pathogenesis of cerebral ischemic injury. 相似文献
135.
AIM:To investigate the electrophysiological characteristics of ventricular myocyte both in subendocardium and in subepicardium during ischemia. METHODS:Using modified Ferrier's method of ischemic and reperfusion injury in isolated guinea pig right ventricular wall. RESULTS: The transmembranal electric activities in subendocardium and in subepicardium were all significantly abnormal, and it was more significant in subendocardium. CONCLUSION: The alteration degree of ventricular myocyte in subendocardium and in subepicardium during ischemia and early reperfusion was different, and this might be the electrophysiological basis of the vulnerability of the subendocardium. 相似文献
136.
AIM: To investigate the mechanisms underlying the protective effect of kidney ischemic preconditioning on rabbit myocardium in case of ischemia-reperfusion and the possible role of oxygen free radicals in the process. METHODS: Animals were divided into four groups: ischemia/reperfusion(I/R), classical ischemic preconditioning(CIPC), kidney ischemic preconditioning (KIPC) and superoxide dismutase in combination with kidney ischemic preconditioning(SOD+KIPC). The endo genous myocardial pretective material, nitric oxide(NO) and 5'-nucleotidase(5'-NT) were checked in four groups. RESULTS: As compared with I/R group, both CIPC and KIPC could ameliorate left ventricular function, reduce plasma PLA2 activity and arrhythogenic rate also, the myocardial 5'-NT and NO production were significantly higher than that of the rabbit of I/R group. However, the protective effect on rabbit myocardium was significantly weakened by the SOD administration before the ischemic preconditioning. CONCLUSION: Protective effect of KIPC on myocardium may be due to increase in endo genous myocardial protective materials, oxygen free radicals may play an important role in the endo genous myocardial protective material release. 相似文献
137.
LI Quan-feng WANG Xiao-ming ZHU Shi-jun AI Jing GAO Huan-huan XU Chang-qing 《园艺学报》2001,17(7):690-691
AIM:To examine the effect of compound salvae-dropping-pill (CSDP) on intracellular free calcium in cultured rat myocardial cells subjected to hypoxia and reoxygenation.METHODS:The Fluo- 3/AM was applied to probe intracellular calcium concentration and the fluorescent intensity was detected using laser confocal microscopy technique.RESULTS:Fluorescent intensity in hypoxia plus CSDP group was significantly lower (1 217.78±312.07) than that of hypoxia group (1 509±508.48), and the Fluorescent intensity of hypoxia/reoxygenation plus CSDP group was also markedly lower (1 567.91±577.61) than that of hypoxia/reoxygenation group (1 617.60±477.53).CONCLUSION:The cultured rat myocardial cells could be effectively protected by administration of CSDP in case of hypoxia and reoxygenation through decreasing the intracellular calcium concentration. 相似文献
138.
XU Han-shi YE Ren-gao YANG Qiong-qiong SUN Lin YANG Nian-sheng LI You-ji ZENG Li-xia 《园艺学报》2001,17(5):428-430
AIM:To investigate the regulatory role of nuclear factor κB (NF-κB) in the expression of interleukin-6 in mesangial cells (MC) induced by interleukin-1β.METHODS:Activation of NF-κB was measured by electrophoresis mobility shift assay (EMSA). RT/PCR and ELISA were used to detect IL-6 mRNA expression and IL-6 production, respectively.RESULTS:rhIL-1β could rapidly stimulate the activation of NF-κB in MC, and increase the expression of IL-6 mRNA and protein. PDTC, one of the inhibitor of NF-κB, could inhibit the expression of IL-6 in mRNA and protein in MC stimulated by rhIL-1β.CONCLUSION:IL-6 expression induced by IL-1β may be regulated by NF-κB in MC, NF-κB may modulate the immune-inflammatory reaction in glomerular disease. 相似文献
139.
本研究选用72只6周龄京白鸡,随机分为A、B、C、D、E和F六组,分别饲喂钙、锌水平不同的日粮(各组锌、钙分别为:21.5ppm,0.95%;21.5ppm,1.95%;21.5ppm,2.95%;49ppm,0.95%;49ppm,1.95%;49ppm,2.95%),进行为期30天的饲养试验。试验中观察增重和临床变化;饲养结束时,取全血、羽毛、胫骨、肝和肾等组织的样本,测定其锌、钙、铁、铜、锰等元素的含量。试验结果是,D组增重和发育良好;A组稍次于D组;其他各组出现程度不同的临床症状,并且这些组所测组织锌含量明显低于D、A组,且其羽毛铁、骨铜、羽毛锰含量明显升高,而羽毛铜、肾铜及肾锰则显著降低。 相似文献
140.
A field experiment was conducted at Central Research Farm, Indian Grassland and Fodder Research Institute, Jhansi to study the effect of seed pre-sowing hardening on seed emergence, physiological behaviour — and seed yield of berseem ( Trifolium alexandrinum L. Var. S-99-1) crop. For this purpose, seed pre-sowing hardening were made by soaking of seeds in tap water for 24 and 36 hours separately and later dried back to their original weight or left undried. These seeds were sown at two depths (5 and 3 cm) and judged against control (no soaking). Results demonstrated that augmented effect of seed hardening on seed emergence and physiological process responsible for seed yield was recorded in descending order of harden seeds (of 24 hours soaking) > non harden seeds (of 24 hours soaking) > harden seeds (of 36 hours soaking); while non-harden seeds of 36 hours soaking adversely affect the plant growth because of leaching of sugar during excess soaking — an element for reduced seed vigour potential. Seed hardening system developed the strength of seed emergence on account of efficient catabolic process releasing high water soluble sugars needed for efficient germination process. Further this process augmented the absorption mechanism of mineral nutrients (particularly phosphorus and nitrogen with marginal variation in calcium) was quite evident at bloom stage — indicating a high metabolic activity during this period. Performance of seed hardening was effective at 5 cm deep sowing. 相似文献