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《佳木斯教育学院学报》2016,(5)
器官移植技术的出现解决了很多因器官衰竭而面临死亡的病人生命,但在其应用范围不断扩大的同时,随之而来的伦理问题也日益突出,其中,涉及供体来源方面问题尤为突出,包括活体器官捐献的知情同意原则以及器官买卖化的问题;尸体器官移植中,如何确定死亡时间;以及利用死囚器官进行移植时应考虑捐献者和接受者的心理问题,这些问题对器官移植技术的发展造成了一定的影响。想要保证我国器官移植工作的有序展开,我们必须从以下几个方面做出实质性努力:尽快建立健全器官移植的法律法规,不断加强公民对器官移植的宣传教育,树立新的伦理观念,建立高效公平合理的器官资源分配体系以及强化相关人员的道德自律。 相似文献
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美国最新研究发现,病人接受不同性别供体心脏移植的后果存在较大区别。接受同性心脏的病人,术后出现严重排异反应的几率较低,一年内存活率比接受异性心脏的病人高20%。 相似文献
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A series of electron donors,including 1,1-cyclopentanecarboxylic acid diethyl ester (CPCADEE),1,1cyclopentanedimethanol acetic diester (CPDMAD),1,1-biethoxymethyl pentane (BEMP),2,2-diethyl diethylmalonate (DEDEM)and 2,2-diethyl-1,3-propanediol acetic diester (DEPDADE),were synthesized by diethyl malonate (DEM).The purities and structures of the above products were characterized by gas chromatography (GC) and gas chromatography-mass spectrometer (GC-MS),respectively.Furthermore,the possible optimal three-dimensional structures of these donors were simulated by means of Gaussian 03 and Chem 3D.Then these electron donors were coordinated with tetrachloro titanium (TiCl 4) and chloride magnesium (MgCl 2)to obtain the catalysts for the polymerization of propylene.The catalytic activities and properties of polypropylene are greatly improved by adding external donor(ED) when CPCADEE or DEPDADE is used as internal donor(ID).However,when BEMP was used as ID,the highest catalytic activity is obtained without adding ED,which can reduce production costs and simplify catalytic synthesis.The experiments indicate that BEMP has the shortest distance of oxygen atoms and the highest electronegativity. 相似文献