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Danger: implants     
The superheated debate over breast implants awakened a sleeping giant of an issue clouding "medical devices"--the government's clumsy nomenclature for any medical product that is not a drug, from breast implants and artificial hips to X-ray machines and surgical thread. Some 130 categories of high-risk devices are in use with little or no proof of safety, reliability or effectiveness. All appeared before 1976, the year that the Food and Drug Administration got the authority to regulate such products. Under activist chief David Kessler and with added clout from a 1990 law, the FDA plans to scrutinize the entire 130-item list. Five will get special attention starting early next year: saline-filled breast implants, inflatable penile implants, testicular implants, heart-bypass pumps and cranial stimulators. U.S. News has looked at all five devices, using FDA data obtained through the Freedom of Information Act. In-depth computer analysis suggested that penile implants deserve closer examination. Why is clear from the following report.  相似文献   
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Isoenzyme band patterns of animal blood erythrocyte acid phosphatase (EAP) and phosphoglucomutase-1 (PGM) were studied by isoelectric focusing on ultrathin polyacrylamide gels. For blood from all animals tested (dog, cat, cow, sheep, and goat), the overall band patterns for both isoenzymes were different from those of the most common human types of these enzymes, although some animal EAP and PGM bands appeared in the human band areas. When mixtures of human and animal red blood cells were studied, it was found that misinterpretation of human types was possible only if the overall band pattern of the mixtures was ignored. For the animal blood tested, the strong PGM bands appearing outside the human band areas could be used as "markers" for the possible presence of animal blood in the samples tested.  相似文献   
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This brief opposes the overturn of "Roe v. Wade" and resists weakening "Roe's central holding" that would allow states to overturn legal abortion. The brief was written for 885 law professors. "Roe" was not a "constitutional aberration," or "an exercise of raw, judicial power." Some members of the Supreme Court seem to think that the state has "an overriding interest" in protecting fetal life. Some Court members have questioned "Roe's" trimester framework. A person's decision to abort should be done privately. If women are not free to choose abortion, they will not have equality. There is an absence of "express rights of privacy and procreational freedom" in the Constitution. "Roe" was 1 instance of the Court's recognition of constitutional rights that are not named explicitly. Historical materials are drawn on to show the link between trends in society and the "judicial recognition of unenumerated rights." The most serious questions about "Roe" deal with its trimester framework. Justice Blackmun's majority opinion said that the 1st trimester of pregnancy was personal. "Roe" said that abortions created a medical risk at the beginning of the 2nd trimester. Therefore, the government was more interested in the health of the mother at that time. The state could then regulate abortion "in ways that are reasonable related to maternal health." The start of the 3rd trimester was when the fetus was viable. The right of a woman to end her pregnancy "offends powerful moral forces." Some of "Roe's" critics had their scientific facts wrong. Medical authorities think Justice O'Connor is mistaken when she says that "Roe" is "on a collision course with itself." The 23rd to 24th week of pregnancies where the fetal organs can "sustain life outside the womb." This has not changed since "Roe" was decided in 1973, nor is it likely to in the future. Some "amici" believe that the state can never have an interest in the fetus. The state can not have an interest in the fetus distinct from the woman who will give birth to it. During previability, restricting a woman's procreational rights would not be scientifically supportable. The state does have an interest in "upholding the value of human life." "Roe" is "within the mainstream" of constitutional jurisprudence and should be reaffirmed.  相似文献   
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"In this essay, certain aspects related to rural-urban mortality differentials in Mexico are analyzed....[These include] the availability, advantages, and limitations of different sources of information and the disparity of levels and tendencies according to particular indicators of acceptable reliability, especially those deriving from recent demographic surveys conducted in Mexico. The findings confirm an inverse ratio between size of settlement and mortality, and reveal a widening of the differentials over time." (SUMMARY IN ENG)  相似文献   
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Robert Higgs 《Public Choice》1989,63(2):175-181
U.S. senators frequently vote against the preference of their constituency, assuming that such a preference exists. Both of a state's senators represent the same constituency. Whenever they split their votes, one or the other is necessarily going against the constituency preference. For the sample of defense-related votes analyzed above, misrepresentation — either observable vote splitting or unobservable vote matches that go against the constituency preference — occurred at least 37 percent of the time, at least 46 percent on one vote. Although party differences accounted for more than two-thirds of the vote splitting, a substantial number of splits remained. Besides, a party difference for a state's senatorial pair is itself problematical.The method employed here can be applied easily to any data whatever on senatorial voting. Its application will show that, quite often, many senators depart from constituency preference. This finding refutes the hypothesis, popular in certain circles, that ours is a more or less perfect political market with little or no scope for ideologically driven voting by legislators.  相似文献   
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