单选题影响心肌传导性的因素有( ) A．心肌细胞的直径 B．邻近部位膜的兴奋性 C．Na+通道状态 D．A+B E．A+B+C

单选题生理情况下，肾小球的滤过分数约为( )(2006年)

单选题兴奋性与抑制性突触后电位相同点是( ) A．突触后膜膜电位去极化 B．是递质使后膜对某些离子通透性改变的结果 C．都与后膜对Na+通透陛增加有关 D．出现“全或无”式电位变化 E．都可向远端传导

单选题患者男性，59岁。慢性肝炎病史20年。近3年来双下肢浮肿。因消化道出血急诊入院。巩膜黄染，皮肤蜘蛛痣，腹水(＋)。脾肋缘下3cm。符合该患者疾病的诊断是

单选题大多数可兴奋细胞接受刺激发生反应的共同表现是产生

单选题最能反映血液中红细胞和血浆相对数量变化的指标是

单选题The housing market has been for two years propping up consumers' spirits while the rest of the economy lies exhausted on the floor, still trying to struggle to its feet. According to the National Association of Realtors, the national median existing-home price ended the year at $164,000, up 7.1 percent from 2001. That's the strongest annual increase since 1980. Although residential real estate activity makes up less than 8% of total U. S. GDP, a housing market like this one can make the difference between positive and negative growth. Most significantly, consumer spending is 66% of GDP, and the purchase of a new home tends to have an "umbrella effect" on the homeowner's spending as he has to stock it with a washer/ dryer, a new big-screen TV, and maybe a swing set for the yard. The main factor in housing's continued strength is a classic economic example of zero-sum boom: the persistent weakness everywhere else. As the 2003 recovery continues to be more forecast than reality. Falling stock prices raised investor appeal for U. S. Treasury Bonds, which in turn, allowed most interest rates to drift even lower. But there are not many signs that there's a bubble ready to burst. December's new record in housing starts, for example, was nicely matched by the new record in new home sales. If you build it, they will buy and even if an economic pickup starts to reduce housing's relative attractiveness, there's no reason why modest economic growth and improved consumer mood can't help sustaining housing's strength. "The momentum gained from low mortgage interest rates will carry strong home sales into 2003, with an improving economy offsetting modestly higher mortgage interest rates as the year progresses," said David Lereah, chief economist at the National Association of Realtors. Just as housing has taken up much of the economic slack for the past two years, both as a comforting investment for fretting consumers and a driver of consumer spending itself, a big bump elsewhere in the economy in 2003 could be housing's downfall. If stocks roar back this spring, capital inflows could steal from the bond market, pushing up long-term interest rates. Or Alan Greenspan and the Fed could do the same to short-term rates, as a way to hit the brakes on a recovery that is heating up too fast. In other words, if everything possible goes wrong for housing, homeowners should have plenty to compensate them in terms bf job security and income hikes.

单选题A．支原体B．噬菌体C．细菌D．酵母

单选题下列不符合浆液性炎的描述是

单选题引起细胞脂肪变性的主要原因不包括

单选题第一信使指的是( ) A．受体 B．基因 C．激素 D．激素-受体复合物

单选题肉眼所见的白色血栓中灰白色赘生物在镜下所见的是

单选题狼疮性肾炎具有诊断意义的病变是

单选题关于儿茶酚胺对心肌的正性变力作用机制，正确的描述是

单选题慢性萎缩l生胃炎时，胃黏膜上皮可化生为

单选题 患者，女，50岁，阴道有不规则分泌物，阴道镜检查，见子宫颈菜花状肿物，表面有出血坏死，最可能的诊断是 ( ) A、子宫颈糜烂 B、子宫颈息肉 C、子宫体癌 D、子宫颈癌 E、子宫颈肥大

单选题心室肌细胞的有效不应期特别长(200～300ms)，其原因主要为

单选题A．凝固性坏B．固缩坏死C．干酪性坏死D．坏疽E．液化性坏死 (1994年)

单选题关于心肌脂肪变性的描述，错误的是

单选题排卵时可用下列哪种激素的高峰作为标志