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灰关联分析应用于因素分析时关联度指标的改进 总被引:8,自引:1,他引:7
本文指出在应用灰关联分析进行因素分析时传统的关联度计算方法的不足,并提出采用新的关联度指标来表示因素之间的关联关系,同时给出了实例介绍计算方法。 相似文献
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The effect of proteases inhibitors, epsilon-amino-caproic acid and gordox, on reproduction of rotavirus SA-11 in MA-104 cells was studied by enzyme immunoassay. These inhibitors were shown to exert an inhibiting effect on rotavirus reproduction. 相似文献
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Mo Weijtens Anke van Spronsen Anton Hagenbeek Eric Braakman Anton Martens 《Human gene therapy》2002,13(2):187-198
Graft-versus-host disease (GvHD), a major complication of allogeneic bone marrow transplantation, has been ascribed to mature T cells in the graft. Because T cells play an important role in engraftment of the bone marrow and decrease the probability of relapse of leukemia, a treatment strategy was developed to preserve the benefits of T cells in the graft and to control the severe complications of GvHD. This can be accomplished by the genetic modification of donor T cells with a suicide gene that allows their selective in vivo elimination and subsequently the abrogation of GvHD. For clinical benefit the alloreactivity of herpes simplex virus thymidine kinase (HSV-TK) gene-transduced T cells should be retained. Therefore, we investigated the influence of gene transduction and the selection procedure on T cells. We demonstrated that activation and culturing of T cells reduce their capacity to induce lethal GvHD in an allogeneic rat bone marrow transplantation model. Furthermore, positive immunomagnetic selection of gene-transduced T cells resulted in loss of the GvHD-inducing capacity of HSV-TK(+) T cells directly after MACS (magnetic cell sorting) selection; this loss could be recovered by a 1-day expansion of the selected T cells. No effect on alloreactivity was observed to be caused by the gene transduction procedure. Our study resulted in the development of an optimized culture and gene transduction protocol with preservation of T cell alloreactivity. Treatment of transplanted rats with ganciclovir resulted in a rapid reduction in the number of HSV-TK(+) T cells in the peripheral blood and in increased survival of the animals. 相似文献
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Dose-response curves of angiotensin I (AI, 1.0-1000.0 pmol) and angiotensin II (AII, 1.25-1250.00 pmol) were obtained in isolated rat hearts subjected to control conditions, mild hypoxia (PO2 = 145 mm Hg), reoxygenation, ischemic (perfusion pressure = 35 mm Hg) and reperfusion. Both AI and AII caused dose-dependent coronary flow (CF) of 26 +/- 3 and 27 +/- 2%, respectively. The effects of both AI and AII were substantially attenuated during hypoxia, but were fully restored upon reoxygenation. During ischemia, the effect of AII was unaltered while the effect of AI was enhanced compared to the control (P less than 0.05). This enhancement was reversible on reperfusion. Cardiac conversion of AI, calculated from ED50 values for AI and AII, was significantly increased during ischemia (P less than 0.05). Infusion of saralasin (0.5-5.0 micrograms/min) did not increase CF in any of the groups. We conclude that (1) the coronary vasoconstrictive effect of AII is preserved in ischemia but attenuated in hypoxia and (2) cardiac conversion of AI to AII is enhanced in hearts injured by ischemia. 相似文献
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李莹教授治疗肾病的经验 总被引:1,自引:0,他引:1
李莹教授毕业于长春中医学院,从事中医内科临床、科研、教学工作50余年,是吉林省首批名中医。她笔耕不辍,讲学传道,精通典籍,厚德载物,度人济世,尤其擅长治疗肾病,是吉林省中医药科学院肾病内科的创始人,并于1998年开始被国家中医药管理局指定为全国名老中医药专家学术经验继承工作指导老师。笔者有幸跟随李老师学习,成为第四批学术经验继承人之一。 相似文献
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Aisling Mary McMahon Fardod O'Kelly Kheng Tian Lim Narayanasamy Ravi John Vincent Reynolds 《Patient safety in surgery》2009,3(1):19
Esophageal perforation is associated with a significant risk of morbidity and mortality. We report herein a case of lye-induced
esophageal perforation managed successfully by employing endoscopic T-tube placement with a successful outcome. 相似文献
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本文放弃传统的MSE准则,从信息论观点出发,发展了随机系统的一种最小熵(ME)控制方法,并从ME控制的等价性、控制限度、存在性、唯一性及必要条件等方面,研究了ME控制的合理性和实用性。ME方法是一种全局分析法,它不仅包含了MSE和MAP准则,且由于全文在整个推导中并未假定高斯性、线性和非时变等,因而原则上适用于诸如非高斯、非线性、时变等传统方法难以处理的复杂系统;不仅适用于工程系统,将其推广到决策、社会、经济等领域会更为自然和切合实际。 相似文献
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