单选题SoBig. F was the more visible of the two recent waves of infection because it propagated itself by e-mail, meaning that victims noticed what was going on. SoBig. F was so effective that it caused substantial disruption even to those protected by anti-virus software. That was because so many copies of the virus spread (some 500,000 computers were infected) that many machines were overwhelmed by messages from their own anti-virus software. On top of that, one common counter-measure backfired, increasing traffic still further. Anti-virus software often bounces a warning back to the sender of an infected e-mail, saying that the e-mail in question cannot be delivered because it contains a virus, soBig. F was able to spoof this system by "harvesting" e-mail addresses from the hard disks of infected computers. Some of these addresses were then sent infected e-mails that had been doctored to look as though they had come from other harvested addresses. The latter were thus sent warnings, even though their machines may not have been infected. Kevin Haley of Symantec, a firm that makes anti-virus software, thinks that one reason SoBig. F was so much more effective than other viruses that work this way is because it was better at searching hard-drives for addresses. Brian King, of CERT, an internet-security centre at Carnegie-Mellon University in Pittsburgh, notes that, unlike its precursors, SoBig. F was capable of "multi-threading", it could send multiple e-mails simultaneously, allowing it to dispatch thousands in minutes. Blaster worked by creating a "buffer overrun in the remote procedure call". In English, that means it attacked a piece of software used by Microsoft's Windows operating system to allow one computer to control another. It did so by causing that software to use too much memory. Most worms work by exploiting weaknesses in an operating system, but whoever wrote Blaster had a particularly refined sense of humour, since the website under attack was the one from which users could obtain a program to fix the very weakness in Windows that the worm itself was exploiting. One way to deal with a wicked worm like Blaster is to design a fairy godmother worm that goes around repairing vulnerable machines automatically. In the case of Blaster some-one seems to have tried exactly that with a program called Welch. However. according to Mr, Haley, Welch has caused almost as many problems as Blaster itself, by overwhelming networks with "pings" --signals that checked for the presence of other computers. Though both of these programs fell short of the apparent objectives of their authors, they still caused damage. For instance, they forced the shutdown of a number of computer networks, including the one used by the New York Times newsroom, and the one organizing trains operated by CSX, a freight company on America's east coast. Computer scientists expect that it is only a matter of time before a truly devastating virus is unleashed.

单选题槟榔治绦虫时，其用量为

单选题诸花皆升，独降

单选题鹿茸的用量为A．10～20gB．3～10gC．1～2gD．0.1～1g

单选题羌活、独活都具有的功效是

单选题气雾剂雾滴的大小，影响其在呼吸道不同部位的沉积，一般起局部作用的粒子( ) A．以0.5～1μm大小为宜 B．以1～2μm大小为宜 C．以2～3μm大小为宜 D．以3～10μm大小为宜 E．以5～12μm大小为宜

单选题治黄疸之要药，阴黄、阳黄皆可配伍使用A．虎杖B．金钱草C．栀子D．茵陈蒿

单选题The American screen has long been a smoky place, at least since 1942's Now, Voyager, in which Bette Davis and Paul Henreid showed how to make and seal a romantic deal over a pair of cigarettes that were smoldering as much as the stars. Today cigarettes are more common on screen than at any other time since midcentury: 75% of all Hollywood films—including 36% of those rated G or PG—show tobacco use, according to a 2006 survey by the University of California, San Francisco. Audiences, especially kids, are taking notice. Two recent studies, published in Lancet and Pediatrics, have found that among children as young as 10, those exposed to the most screen smoking are up to 2.7 times as likely as others to pick up the habit. Worse, it's the ones from nonsmoking homes who are hit the hardest. Now the Harvard School of Public Health (HSPH)—the folks behind the designated-driver campaign—are pushing to get the smokes off the screen. "Some movies show kids up to 14 incidents of smoking per hour," says Barry Bloom, HSPH's dean. "We're in the business of preventing disease, and cigarettes are the No. 1 preventable cause." Harvard long believed that getting cigarettes out of movies could have as powerful an effect, but it wouldn't be easy. Cigarette makers had a history of striking product-placement deals with Hollywood, and while the 1998 tobacco settlement prevents that, nothing stops directors from incorporating smoking into scenes on their own. In 1999 Harvard began holding one-on-one meetings with studio execs trying to change that, and last year the Motion Picture Association of America flung the door open, inviting Bloom to make a presentation in February to all the studios. Harvard's advice was direct: Get the butts entirely out, or at least make smoking unappealing. A few films provide a glimpse of what a no-smoking or low-smoking Hollywood would be like. Producer Lindsay Doran, who once helped persuade director John Hughes to keep Ferris Bueller smoke-free in the 1980s hit, wanted to de the same for the leads of her 2006 movie Stranger Than Fiction. When a writer convinced her that the character played by Emma Thompson had to smoke, Doran relented, but from the way Thompson hacks her way through the film and snuffs out her cigarettes in a palmful of spit, it's clear the glamour's gone. And remember all the smoking in The Devil Wears Prada? No? That's because the producers of that film kept it out entirely—even in a story that travels from the US fashion world to Paris, two of the most tobacco-happy places on earth. "No one smoked in that movie," says Doran, "and no one noticed." Such movies are hardly the rule, but the pressure is growing. Like smokers, studios may conclude that quitting the habit is not just a lot healthier but also a lot smarter.

单选题具有温肾补精、益气养血功效的药物是( )(2007年第39题)

单选题性温有小毒，善治鼻渊头痛的药是：

单选题 不能采用热压法灭菌的是（ ）。 A、硝酸纤维素 B、醋酸纤维素 C、聚四氟乙烯 D、聚氯乙烯

单选题清热解毒，凉血消斑，善治温热病气血两燔发斑证的药是A．大青叶B．板蓝根C．青黛D．贯众

单选题具有清肺化痰止咳平喘之功的药物为：

单选题有小毒的药物是

单选题下列哪项不是巴豆的功能?

单选题 三维运动混合机最佳填充率为（ ）左右。 A、40％ B、50/% C、60/% D、80％

单选题治热结便秘，首选（ ）

单选题白及的性味为：

单选题既能降逆止呕，又能助阳止泻的药物是

单选题根据五味的作用，请判断下列药物中哪组完全属于辛味药A．麻黄、紫菀、乌梅B．干姜、细辛、诃子C．沉香、乌梅、荔枝核D．紫苏、木香、川芎