手功能开始发育阶段（）。A.0～3个月 B.4～6个月 C.7～9个月 D.10～1 发布时间：2017-05-11 20:38 │ 来源：www.tikuol.com 题型：单项选择题 问题： 手功能开始发育阶段（）。A.0～3个月B.4～6个月C.7～9个月D.10～12个月E.15～12个月
题型：单项选择题 男性，57岁，既往体健，发热、咳嗽、咳黄脓痰3天，加重并气促1天入院。查体：体温39.5℃，呼吸32/分钟，脉搏112/分钟，血压88/56mmHg，神志清楚，精神萎靡，口唇发绀，右下肺闻及湿性啰音。胸片右下肺野见渗出病灶。初步诊断（）A.普通感冒B.上呼吸道感染C.重症社区获得性肺炎D.下呼吸道感染E.发热待查 查看答案
题型：单项选择题 某些种类的海豚利用回声定位来发现猎物：它们发射出滴答的声音，然后接收水域中远处物体反射的回音。海洋生物学家推测这些滴答声可能有另一个作用：海豚用异常高频的滴答声使猎物的感官超负荷，从而击晕近距离的猎物。 以下哪项如果为真，最能对上述推测构成质疑( )A．海豚用回声定位不仅能发现远距离的猎物，而且能发现中距离的猎物B．作为一种发现猎物的讯号，海豚发出的滴答声，是它的猎物的感官所不能感知的，只有海豚能够感知从而定位C．海豚发出的高频讯号即使能击晕它们的猎物，这种效果也是很短暂的D．蝙蝠发出的声波不仅能使它发现猎物，而且这种声波能对猎物形成特殊刺激，从而有助于蝙蝠捕获它的猎物 查看答案
题型：单项选择题 Passage Five As students return to school this fall, parents will again worry about new illnesses as kids come into contact with flu germs. There are other risks they should worry about—illnesses caused by the common bugs and rodents found in school buildings. Perhaps the even more dangerous pests however are those individuals who prevent school administrators from swiftly addressing these problems. Anti-chemical activists have pushed, and nearly 20 states and local governments have passed, 1 aws to eliminate or drastically reduce the use of pesticides in schools. Yet pesticides are used to control roaches, mice, rats, mosquitoes, and other pests. The public health implications of allowing these things to get out of control should be obvious: increased allergies and illnesses related to insect and rodent bites. Some states have passed a seemingly more reasonable policy that demands that school administrators provide notification 48 to 72 hours before using pesticides. But such laws allow problems to escalate during wailing periods when an urgent response is warranted. Notification paperwork burdens also consume limited financial resources. Journalist Steve Milloy reported that the notification law of Maryland costs the state’s schools $32.000 annually. Parents should fear these laws and the pests they harbor more than the pesticides. Environmental Protection Agency (EPA) pesticide standards are so exceedingly cautious that the risks are tiny when the product is used according to label directions. An analysis done by the University of Texas found that the EPA’s risk estimates overstate pesticide exposure damage at a level hundreds of thousands of times greater than the risk of actual exposure. Meanwhile, many of the pests in schools pose serious risks. Allergies and asthma are a particular concern. According to one study published in Environmental Health Perspectives: "Allergens associated with dust mites and cockroaches are probably important in both onset and worsening of asthma symptoms for children who are chronically exposed to these agents." Cockroach allergies are particularly problematic. Children who suffered from this type of allergy missed more days of school and lost more sleep than children suffering from other allergies. Prudent use of chemicals—not reduced pesticide use—can be a big part of the solution. A study in the Journal of Allergies and Clinical Immunology showed that use of chemical baits and regular cleaning can reduce indoor cockroach allergens to levels below that which causes allergies. If people are truly concerned about public health in schools, it’s time to start looking at priorities. Rather than liberate the pests, they should liberate the schools from silly government regulations and dangerous vermin.What is the main idea of the passageA．New chemicals should be developed to control pestsB．Pesticides should be used frequently to control pestsC．Some policies have ruined the efforts to control pestsD．Schools have ignored the need to control pests 查看答案