对横纹肌有良好的刺激收缩作用的是(     )

急性广泛前壁心肌梗死，发病后5小时，首选的治疗措施是(     )

下列各项中，不属于企业费用要素的是（  ）。

根据应急预案体系的构成，针对深基坑开挖编制的应急预案属于（ ）。

机床存在的机械危险大量表现为人员与可运动件的接触伤害，是导致金属切削机床发生事故的主要危险。旋转运动的机械部件将人的长发、手套、肥大衣袖或下摆缠进回转件，继而引起对人的伤害，属于机械伤害中的（  ）。

请阅读  Passage 1,完成第  21~25小题 。

Passage 1

First two hours, now three hours-this ishow far in advance authorities are recommending people show up to catch adomestic flight, at least at some major U.S. airports with increasingly massivesecurity lines.

Americans are willing to toleratetime-consuming security procedures in return for increased safety. The crash ofEgyptAir Flight 804, which terrorists may have downed over the Mediterranean Sea,provides another tragic reminder of why. But demanding too much of airtravelers or providing too little security in return undermines public supportfor the process. And it should: Wasted time is a drag on Americans ' economicand private lives, not to mention infuriating.

Last year, the Transportation SecurityAdministration (TSA) found in a secret check that undercover investigators wereable to sneak weapons-both fake and real-past airport security nearly everytime they tried. Enhanced security measures since then, combined with a rise inairline travel due to the improving economy and low oil prices, have resultedin long waits at major airports such as Chicago ' s O ' Hare International. Itis not yet clear how much more effective airline security has become-but thelines are obvious.

Part of the issue is that the governmentdid not anticipate the steep increase in airline travel, so the TSA is nowrushing to get new screeners on the line. Part of the issue is that airportshave only so much room for screening lanes. Another factor may be that morepeople are trying to overpack their carry-on bags to avoid checked-baggagefees, though the airlines strongly dispute this.

There is one step the TSA could take thatwould not require remodeling airports or rushing to hire: Enroll more people inthe PreCheck program. PreCheck is supposed to be a win-win for travelers andthe TSA. Passengers who pass a background check are eligible to use expectedscreening lanes. This allows the TSA to focus. on travelers who are higherrisk, saving time for everyone involved. The TSA wants to enroll 25 millionpeople in PreCheck.

Ithas not gotten anywhere close to that, and one big reason is sticker shock:Passengers must pay $85 every five years to process their background checks.Since the beginning, this price tag has been PreCheck ' s fatal flaw. Upcomingreforms might bring the price to a more reasonable level. But Congress shouldlook into doing so directly, by helping to finance PreCheck enrollment or tocut costs in other ways.

The crash of EgyptAir Flight 804 is mentioned to_____.  .

患者女，15岁。双侧下颌第一磨牙松动Ⅰ度。有浅牙周袋，袋内检出大量Aa菌。对该患者适宜的预防和药物治疗为

在我国实施人类辅助生殖技术，下列各项中违背卫健委制定的伦理原则的是（    ）

传染病预防中针对传播途径的措施是

患者，女，43岁。左乳浸润性导管癌术后放、化疗3年后复发，左肺门、左锁骨上、左腋窝淋巴结转移，现采用卡培他滨+多西他赛行复发后第1周期化疗，化疗后第2日，患者出现重度恶心、呕吐。根据化疗药物致吐分级，宜选用的对症治疗药物是（   ）