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161.
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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In this article we examine how increasing the reimbursement of physicians and expanding Medicaid eligibility affect access to care for children in Cook County, Illinois, which overlies Chicago. Using Medicaid claims and other data at the zip-code level, we compare the places where Medicaid children live with the places where all the physicians who treat children and those who accept Medicaid patients have their practices. Our findings suggest that the recent changes in legislation are unlikely to benefit extremely poor children, who are more likely to live in depressed inner-city areas, where there are few physicians. "Near-poor" children whose homes are dispersed throughout the county, who are now eligible for Medicaid as a result of the recent changes, are likely to see improvements in their access to care. Further changes in policy, aimed at enhancing the capacity of institutions providing care, could improve access for the children of the inner city.  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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Programme based on mathematical model of the process of dead body temperature changing was developed for estimation of postmortem interval. Automatic retrieval of problem solution was performed on programmable microcalculators of "Electronica MK-61" type using adaptive approach. Diagnostical accuracy in case of dead body being preserved in permanent cooling conditions is +/- 3%.  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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