单选题
Men and women may need to be treated differently when it comes to pain. Researchers in California have found that certain painkillers provide greater and longer-lasting relief for women than they do for men. This suggests that the physiology of pain differs between the sexes. The discovery could lead doctors to change the way they prescribe analgesic drugs. In controlled experiments, women often report higher levels of pain. But when it comes to prescribing and developing new analgesics, medical science usually ignores the sex of the patient, says Jon Levine, a specialist in inflammatory diseases at the University of California, San Francisco. Levine says that sexual differences were the last thing on his mind when his research group started studying a class of analgesics called kappa-opioids, which are chemical cousins to morphine and heroin. The researchers found that the drugs were less effective in controlling pain than their better-known kin(家属). But when they tried to publish their results, an expert reviewer spotted the fact that some of the treatment groups contained more women than men, and suggested that the researchers reanalyze the data to see if this accounted for their results. "To our surprise, all the effect could be ascribed to sex," says Levine. To test the effect of sex directly, Levine's team recruited 20 men and 28 women who were due(预订) to have their wisdom teeth removed. After surgery, the patients first evaluated their pain as the origin alan-aesthesia wore off, and then every 20 minutes after they were given a shot of a kappa-opioid. The link between sex and the effectiveness of the drugs was clear, the researchers report in this month's issue of Nature Medicine. Although the women reported a higher level of pain shortly after surgery, 20 minutes after a dose of the opioid their pain had lessened to a greater degree than it had for the men. And the women' s pain relief continued for hours after the drug' s effects began to wane in the men. "I'm very excited about this result," says Karen Berkey, a pain researcher at Florida State university in Tallahassee. In addition to sex differences, she would now like to see researchers explore other factors—such as age that might influence the effectiveness of painkillers. If scientists can understand why such differences exist, it may be possible to develop "designer" painkillers tailored (适应) to particular types of patient. Levine says the findings should prompt researchers to reexamine drugs abandoned as useless simply because they did not work in men-only trials. Whatever the outcome of the research, Levine says that a lot of the credit is due to the unknown reviewer who readjusted the focus of his work." Everyone in the group is appreciative," he says, "we' re just sorry reviewing is done anonymously (匿名方式) and we couldn't thank this person."
单选题
As the research indicates the efficacy of analgesic drugs______.