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71.
Classifying research proposals by risk of harm is fundamental to the approval process and the most pivotal risk category in most regulations is that of "minimal risk." If studies have no more than a minimal risk, for example, a nearly worldwide consensus exists that review boards may sometimes: (1) expedite review, (2) waive or modify some or all elements of informed consent, or (3) enroll vulnerable subjects including healthy children, incapacitated persons and prisoners even if studies do not hold out direct benefits to them. The moral and social purposes behind this threshold are discussed along with relevant views from the National Commission, NBAC, NHRPAC, Grimes v. Kennedy Krieger Institute, The Nuremberg Code, and The WMA's Declaration of Helsinki. Representative policies from Australia, Canada, South Africa, the U.S., and CIOMS are reviewed revealing different understandings of this sorting threshold. Six of nine frequently cited interpretations of "minimal risk" are untenable. The "absolute" interpretation of the "routine examination" standard is defended as best.  相似文献   
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There is little information on the lead levels of Indian children nationally. In the late 1990s, members of the Chippewa and Cree tribes living on the Rocky Boy Reservation near Box Elder, Montana, were concerned about environmental pollution and how it might be affecting the health of their children. With financial assistance from the Environmental Protection Agency, the tribes designed and implemented an innovative lead screening program for young children. Because most children on the reservation participated in WIC and Head Start, those programs were used to identify and screen close to 100% of young children on the reservation. The average blood lead level for children ages 1-5 on the Rocky Boy reservation was 2.4 micrograms/dL, which is not significantly different from that of children of the same age nationally. The project showed that Indian families will participate readily in screening programs that may improve their children's health.  相似文献   
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ABSTRACT:  Infants and children have special issues with regard to genital disease. Infants are incontinent, and have an increase in local irritation and infection risk. In addition, the adult sex hormones which enhance the health of genital skin are deficient. Also, the choice of therapy must be modified to take into account the more fragile nature of prepubertal skin, the tolerance of children to painful treatments, and the lack of experience of some medications in children.  相似文献   
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OBJECTIVE: Patterns of pubertal maturation may have an impact on several risk factors associated with adult morbidity and mortality, such as obesity. We examined the relationship of the initial manifestation of puberty in girls with anthropometric measures, as well as age at menarche. METHODS: White females (n = 1166, ages 9 and 10 at intake) were followed with annual visits for 10 years. Physical examinations included height, weight, skinfold thicknesses, and pubertal maturation assessment. RESULTS: During the course of the study, 443 of 859 eligible females (51.6%) were observed to have asynchronous maturation in the development of puberty, that is, initial areolar/breast (thelarche pathway) or pubic hair (adrenarche pathway) development, without development of the other characteristic. Using a longitudinal regression model, significant interactions were noted between initial pubertal manifestation and years since onset of puberty on the following outcomes: sum of skinfolds thickness, percent body fat, waist-to-hip ratio, and body mass index (BMI). However, age of onset of pubertal maturation was the same in the 2 groups (10.7 years). Females in the thelarche pathway had earlier menarche (12.6 vs 13.1 years) as well as greater skinfolds, body fat, and BMI at the time of menarche. Females in the thelarche pathway also had greater body fat and BMI 1 year before puberty and throughout puberty compared with those in the adrenarche pathway. CONCLUSIONS: Females who enter puberty through the thelarche pathway, as compared with the adrenarche pathway, had greater sum of skinfold thicknesses, BMI, and percent body fat 1 year before the onset, as well as throughout, puberty. Because larger body composition and earlier age of menarche of females in the thelarche pathway parallel the epidemiologic profiles of women who are obese or at risk for obesity, these females may be at greater risk for adult obesity.  相似文献   
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This review describes the variation of glucose-6-phosphate dehydrogenase (G6PD) activity in the main neurons of the molecular and granular layers as well as in the deep nuclei of the cerebellum as observed so far by optical and electron microscopy studies. Light microscopy and semiquantitative microphotometry of histochemical staining showed that the highest G6PD activity was expressed by Purkinje cells and neurons of the deep cerebellar nuclei; the elements of the molecular layer showed a diffuse G6PD staining, while the granular layer displayed only scattered G6PD activity. Electron microscopy analysis showed that the basket and stellate cells, as well as the Golgi cells, have a remarkable G6PD activity, while in the granule cells the enzyme was barely detectable. The results show that cerebellar G6PD activity changes with different neuron types as a function of its role in sustaining NADPH dependent pathways in these cells.  相似文献   
78.
The U.S. Supreme Court's seminal 1978 Bakke decision, now 25 years old, has an ambiguous and endangered legacy. Justice Lewis Powell's opinion provided a justification that allowed leaders in medical education to pursue some affirmative action policies while at the same time undermining many other potential defenses. Powell asserted that medical schools might have a "compelling interest" in the creation of a diverse student body. But Powell's compromise jeopardized affirmative action since it blocked many justifications for responding to increases in political opposition and legal challenges. The Bakke decision and its moral background and legal legacy are traced and analyzed. Despite recent legal setbacks, the framework sketched by Powell can be used to defend diversity in medical education both morally and legally as a "compelling state interest." Because trust is a central component of the physician-patient relationship and a prerequisite to the profession's ability to provide effective medical care, the state has a compelling interest in training physicians with whom patients can feel comfortable and safe if the population is (1) distrustful; (2) underserved; (3) faces significant discrimination in the allocation of benefits, goods and services and (4) affirmative action programs would be likely to promote their trust in the system. Similar narrowly-tailored arguments could be used in other professions and for other groups. Bakke is an important background for the pending Grutter case.  相似文献   
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