单选题下列中最常见的慢性阻塞性肺病是

单选题男性，16岁。左手烫伤，红肿，少数水泡，无感染。经治疗痊愈，局部皮肤组织的病理变化表现为

单选题在某凝血功能障碍患者血浆中加入足量组织因子和Ca 2+ 后，血浆凝固时间仍明显较正常人延长，该患者可能缺乏下列哪种物质

单选题哪种细胞属于永久性细胞( )(1994年)

单选题下列有关肿瘤免疫的描述，不恰当的是

单选题特殊动力效应最为显著的食物是( )(2008年)

单选题A．只有传导性而无自律性、传导速度很慢B．只有自律性而无传导性C．既有自律性也有传导性、传导速度较慢D．既有自律性也有传导性、传导速度较快E．既有律性也有传导性、自律性较高 (1988年)

单选题下列属于液化性坏死的是

单选题A．淋巴结结构破坏，大量单一肿瘤性细胞增生B．淋巴结结构破坏，多种炎细胞及R-S细胞增生C．淋巴结内瘤细胞排列成滤泡结构D．淋巴结结构破坏，大量原始粒细胞浸润

单选题关于类风湿小结的叙述，下列哪项正确

单选题患者女性，18岁，1周来高热、恶心、呕吐，嗜睡，皮肤、巩膜黄染，肝区疼痛。ALT 150U／L，胆红素350mg／L，HBsAg(＋)。住院2天，出现昏迷。因胃肠道广泛出血而死亡。诊断是

单选题下列符合轻微病变性肾小球肾炎的临床表现是

单选题下列属于伪膜性炎的是

单选题RNA复制时所需要的原料是

单选题声波由鼓膜经听骨链到达卵圆窗膜时，其振动的

单选题高血压患者无须行特殊术前准备的血压标准是

单选题The topic of cloning has been a politically and ethically controversial one since its very beginning. While the moral and philosophical aspects of the issues are entirely up to the interpretation of the individual, the application of cloning technology can be studied objectively. Many in the scientific community advocate the use of cloning for the preservation and support of endangered species of animals, which aside from cloning, have no other practical hope for avoiding extinction. The goal of the use of cloning to avoid extinction is the reintroduction of new genes into the gene pool of species with few survivors, ensuring the maintenance and expansion of genetic diversity. Likely candidates for this technique are species known to have very few surviving members, such as the African Bongo Antelope, the Sumatran Tiger, and the Chinese Giant Panda. In the case of Giant Panda, some artificial techniques for creating offspring have already been performed, perhaps paving the way for cloning as the next step in the process. With the estimated population of only about 1000 Giant Pandas left in the world, the urgency of the situation has led to desperate measures. One panda was born through the technique of artificial insemination in the San Diego Zoo in the United States. "Hua Mei" was born in 1999 after her parents, Hsing-Hsing and Ling-Ling, had trouble conceiving naturally. The plan to increase the Giant Panda population through the use of cloning involves the use of a species related to the Giant Panda, the American Black Bear. Egg cells will be removed from female black bears and then fertilized with Panda cells such as those from Ling-Ling or Hsing-Hsing. The fertilized embryo will then re-implanted into the black bear, where it will grow and mature, until a new panda is delivered from the black bear host. Critics of cloning technology argue that the emphasis on cloning as a method by which to preserve species will draw funding away from other methods, such as habitat preservation and conservation. Proponents of cloning counter that many countries in which many endangered species exist are too poor to protect and maintain the species' habitats anyway, making cloning technology the only practical way to ensure that those species survive to future generations. The issue is still hotly debated, as both sides weigh the benefits that could be achieved against the risks and ethical concerns that constantly accompany any argument on the issue.

单选题A．1B．2C．3D．4

单选题关于肾盂肾炎的概念，下列哪项最确切

单选题下述哪一序列能形成发夹结构