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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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Analysis of a sample of 1108 radii corresponding to 567 black and white North Americans in the Terry Collection at the Smithsonian Institution demonstrates that the diameter of the radial head is an accurate sex discriminator for human remains. A simple "radial-head method" of sex determination consists of measuring the maximum and minimum diameters of the head and comparing such measurements with the test cutoff points. The subject is female when the maximum radial head diameter (either left or right) is less than or equal to 21 mm, and male when the maximum diameter (either left or right) is greater than or equal to 24 mm. The same decisions apply to the minimum diameters of 20 mm or less and 23 mm or more, respectively. When the maximum diameter is 23 mm or the minimum is 22 mm, the subject is more likely male; when the maximum diameter is 22 mm or the minimum is 21 mm, the subject is more likely female. The sample frequency of any one of these latter diameters is never more than 16%. Cross-validation of the method with a sample of 50 pairs of radii of the Terry Collection, different from the original specimens, resulted in 92% sexing accuracy when using the left radius singly, 94% accuracy when using the right radius singly, and 96% accuracy when using both radii jointly.  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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So far, the law in the Federal Republic of Germany still allows the injection of fresh-cell preparations from animals as a roborant to increase the vitality of the organism and to strengthen the body's immune defense system. The use of "sicca-cell" preparations was provisionally forbidden in 1987 by the Federal Health Organization (Bundesgesundheitsamt; BGA). Prohibition of fresh-cell injections would have exceeded the authority of this office, although the same serious reservations also applied in the case of this treatment method. Several publications that have appeared since 1955 have reported serious complications of this therapy, some life-threatening and some even lethal. Two further cases are now added: (1) A woman aged 69 had been receiving treatment with cell injections for 9 years. Immediately after an injection of sicca cells she collapsed and was hospitalized; 7 days thereafter she developed an ascending paralysis with increasing inability to swallow or breathe. She died 25 days after the injection as a consequence of central and peripheral respiratory failure. Autopsy revealed the alterations typical for acute Landry-Guillain-Barré-Strohl syndrome. (2) A 76-year-old healthy woman had been receiving treatment with fresh-cell preparations for several years. After an injection of cell suspensions a painful local swelling was observed. The symptoms were interpreted as the consequence of an iatrogenic local hematoma, and repeated punctures were performed to obtain blood. The patient was transferred to a surgical department for further therapy. Two days after the injection she suddenly died with signs of acute cardiovascular failure. Autopsy revealed the signs of a fulminating clostridial infection and also the characteristic signs of Landry-Guillain-Barré syndrome with involvement of the autonomic nervous system. In both cases the development of an inflammatory process in the peripheral nervous system could be interpreted as an immune-mediated allergic disease, related to the repeated injection of heterologous antigenic material containing nervous tissues. This hypothesis would also explain the two other cases already published and would be consistent with the observed perivenous leukoencephalopathy of the central nervous system. The human disease pictures correspond to the well-established animal models of EAEM (experimental allergic encephalomyelitis) and EAN (experimental allergic neuritis). The pathogenesis is discussed; the major role of the central and peripheral nervous system is stressed, with special reference to the risk of acute autonomic failure. The need for specific autopsy techniques for the investigation of the entire nervous system, including spinal cord, roots, spinal ganglia and peripheral nerves with sympathetic chains, is raised.  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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