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1.
Previously we have noted that fluid obtained from ten-day-old healing wounds noncytotoxically inhibits the blastogenesis of lymphocytes in response to mitogens or antigens. Since these lymphocytic responses are interleukin 2 (IL-2)-mediated, we looked for a specific IL-2 inhibitor in wound fluid. We have found that wound fluid blocks the response of thymic lymphocytes and of two cloned T-helper cell lines (D10 and HT2) to exogenous human recombinant IL-2. The wound fluid enhances fibroblast proliferation, thus demonstrating that its proliferative inhibitory activity is specific for lymphocytes. The findings suggest that wound fluid contains a factor that impairs lymphocyte response to IL-2, probably at the receptor or postreceptor level.  相似文献   
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To identify high-risk patients with acute myocardial infarction, we compared admission values of two-dimensional echocardiography and hemodynamic monitoring. Left ventricular wall motion score (WMS), left ventricular stroke work index (LVSWI), and pulmonary capillary pressure (PCP) were obtained in 77 patients without clinical signs of heart failure. Progression into Killip grade 3 or 4 was found in 16 of 77 patients (21%) within 32 +/- 6 hours (mean +/- 1 standard deviation) after admission. Mean WMS, LVSWI, and PCP in those patients who developed severe pump failure were significantly different from those who did not: 13.4 +/- 4.9 versus 7.3 +/- 4, 30 +/- 4 versus 46 +/- 11 gm/m2, and 21 +/- 8 versus 12 +/- 6 mm Hg, respectively. Sensitivity of WMS of greater than 7 and LVSWI of less than 35 gm/m2 in predicting Killip grade 3 or 4 was 88% and 94%, specificity was 57% and 87%, positive predictive value was 35% and 65%, and negative predictive value was 95% and 98%. Sensitivity of PCP was low (50%). Early identification of patients developing myocardial rupture or reinfarction was limited by both methods. We conclude that echocardiographic examination on admission in patients with acute myocardial infarction provides an alternative approach for early identification of low-risk patients.  相似文献   
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An RNA-binding motif (RBM) gene family has been identified on the human Y chromosome that maps to the same deletion interval as the 'azoospermia factor' (AZF). We have identified the homologous gene family (Rbm) on the mouse Y with a view to investigating the proposal that this gene family plays a role in spermatogenesis. At least 25 and probably >50 copies of Rbm are present on the mouse Y chromosome short arm located between Sry and the centromere. As in the human, a role in spermatogenesis is indicated by a germ cell-specific pattern of expression in the testis, but there are distinct differences in the pattern of expression between the two species. Mice carrying the deletion Yd1, that maps to the proximal Y short arm, are female due to a position effect resulting in non-expression of Sry ; sex-reversing such mice with an Sry transgene produces males with a high incidence of abnormal sperm, making this the third deletion interval on the mouse Y that affects some aspect of spermatogenesis. Most of the copies of Rbm map to this deletion interval, and the Yd1males have markedly reduced Rbm expression, suggesting that RBM deficiency may be responsible for, or contribute to, the abnormal sperm development. In man, deletion of the functional copies of RBM is associated with meiotic arrest rather than sperm anomalies; however, the different effects of deletion are consistent with the differences in expression between the two species.   相似文献   
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癌基因c-erbB-2在膀胱移行细胞癌中的扩增   总被引:2,自引:1,他引:1  
赵致广  张莉莉 《医学争鸣》2000,21(4):482-482
0 引言 为探讨癌基因 c- erb B- 2的扩增与膀胱移行细胞癌(TCC)的关系 ,我们以斑点杂交的方法对 40例膀胱 TCC标本中 c- erb B- 2的扩增情况进行了检测 ,以期明确 c- erb B- 2扩增与膀胱 TCC病理分级及患者预后的关系 .1 材料和方法  40例膀胱 TCC患者术后石蜡包埋标本 ,随访 5~ 10 a. 11例正常膀胱粘膜石蜡标本作为对照 . c- erb B-c DNA p CER2 0 4质粒由东京大学提供 ,Bothringer缺口平移 DNA标记试剂盒及 32 P标记 d CTP购于北京福瑞公司 .所有石蜡标本经脱蜡及蛋白酶消化 ,以酚 /氯仿抽提 DNA,乙醇沉淀 .每份样品取…  相似文献   
10.
Purpose To characterize and predict cycles generating slowcleaving embryos in in vitro fertilization, 86 cycles were retrospectively divided into two groups (slow, n=41, and fast, n=45 according to whether the number of blastomeres per embryo on day 3 was or > than the mean of the distribution, respectively.Results Cycles generating slowcleaving embryos were treated with luteinizing hormonereleasing hormone agonist before ovarian stimulation for a shorter period (12.1±0.5 versus 15.6±1.1 days; P0.01) and had higher immaturity grade of oocyte-corona-cumulus complexes which resulted in embryos (1.6±0.1 vs 1.3±0.1; P0.05) when compared to cycles producing fastcleaving embryos. Both variables entered in a logistic regression model applied in order to predict the probability of a cycle generating slowcleaving embryos (goodness-of-fit chisquare=180.0, degrees of freedom (df)=80, P=0.4786. This model predicted correctly 86.7% (13 of 15) of cycles generating slowcleaving embryos and 83.3% (10 of 12) of cycles producing fastcleaving embryos when the estimated probability of a cycle producing slowcleaving embryos was 0.7 or 0.3, respectively.Conclusion Shorter treatment with hormone-releasing hormone agonist before ovarian stimulation and higher immaturity grade of oocyte-corona-cumulus complexes which result in embryos are predictive characteristics of in vitro fertilization cycles generating slow-cleaving embryos.  相似文献   
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