学科分类

已选分类 医学
问答题给家兔(体重2.5kg)静脉注射20/%的葡萄糖溶液5ml后,尿量有何变化,为什么?
进入题库练习
问答题何谓风湿病?试述风湿性心脏病的病理学特征。
进入题库练习
问答题试述糖皮质激素的生理作用及分泌的调节。
进入题库练习
问答题试述弥漫性非毒性甲状腺肿的病因、发病机制和甲状腺的主要病理变化
进入题库练习
问答题Since the days of Aristotle, a search for universal principles has characterized the scientific enterprise. In some ways, this quest for commonalities defines science. Newton's laws of motion and Darwinian evolution each bind a host of different phenomena into a single explicatory frame work. (46) In physics, one approach takes this impulse for unification to its extreme, and seeks a theory of everything—a single generative equation for all we see. It is becoming less clear, however, that such a theory would be a simplification, given the dimensions and universes that it might entail, nonetheless, unification of sorts remains a major goal. This tendency in the natural sciences has long been evident in the social sciences too. (47) Here, Darwinism seems to offer justification for it all humans share common origins it seems reasonable to suppose that cultural diversity could also be traced to more constrained beginnings. Just as the bewildering variety of human courtship rituals might all be considered forms of sexual selection, perhaps the world's languages, music, social and religious customs and even history are governed by universal features. (48) To filter out what is unique from what is shared might enable us to understand how complex cultural behavior arose and what guides it in evolutionary or cognitive terms. That, at least, is the hope. But a comparative study of linguistic traits published online today supplies a reality check. Russell Gray at the University of Auckland and his colleagues consider the evolution of grammars in the light of two previous attempts to find universality in 'language. The most famous of these efforts was initiated by Noam Chomsky, who suggested that humans are born with an innate language—acquisition capacity that dictates a universal grammar. A few generative rules are then sufficient to unfold the entire fundamental structure of a language, which is why children can learn it so quickly. (49) The second, by Joshua Greenberg, takes a more empirical approach to universality identifying traits (particularly in word order) shared by many language which are considered to represent biases that result from ~nitive constraints Gray and his colleagues have put them to the test by examining four family trees that between them represent more than 2,000 languages. (50) Chomsky's grammar should show patterns of language change that are independent of the family tree or the pathway tracked through it. Whereas Greenbergian universality predicts strong co-dependencies between narticular types of word-order relations.Neither of these patterns is borne out by the analysis, suggesting that the structures of the languages are lire age-specific and not governed by universals
进入题库练习
问答题参与窦房结起搏活动的电流有哪些?
进入题库练习
问答题甲状腺激素分泌过多或过少对机体有什么影响?
进入题库练习
问答题高热患者在饮食和用药上要注意哪些问题,为什么?
进入题库练习
问答题缺O2、CO2蓄积、血液pH降低对呼吸运动有何影响?并分析其作用机制。
进入题库练习
问答题发热与过热有何区别?
进入题库练习
问答题试述组织液的生成过程(机制)。
进入题库练习
问答题简述慢性溃疡病的病理形态学变化。
进入题库练习
问答题低动力型休克微循环有效灌流量减少的机制是什么?
进入题库练习
问答题试述神经纤维产生一次兴奋后,兴奋性的周期性变化及机理。
进入题库练习
问答题列表说明各种类型缺氧的血氧变化特点。
进入题库练习
问答题根据病因不同,试述Cushing综合征的类型及病变特点。
进入题库练习
问答题试述交感与副交感神经系统的结构与功能特征。
进入题库练习
问答题患者男,66岁,因患肺癌入院。住院数日来,安静卧床休息,等待手术。一日上厕所,突然晕倒,经抢救无效死亡。 尸体解剖所见:营养状况良好,无明显恶病质。冠状动脉未见异常,未见心肌梗死,未见心脏破裂。左肺上叶近肺膜处有一6cm×6.2cm肿块,切面灰白色,局部有出血和坏死,肺膜与胸壁明显粘连。左右肺动脉内有灰褐色与灰白色相间的网柱形固体物阻塞。右股静脉呈索状,切开见有暗红色团块状物,间有灰白色条纹,质松脆,局部与血管壁粘连,其远段为均匀暗红色。镜下见固体团块物由粉红色及红色两种成分构成,前者呈分支小梁状。 思考题:
进入题库练习
问答题
进入题库练习
问答题小叶性肺炎
进入题库练习