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Despite recent genetic evidence and the promise of individualized medicine, there is a continuing interest in using self-identified categories of race and ethnicity as variables in scientific and medical research. The U.S. Food and Drug Administration recently proposed a standardized approach for the collection of race and ethnicity data in clinical trials. We believe that this move fails to acknowledge new scientific data and recommend that relevant data from individuals be collected and used rather than broad group statistics. We also encourage that increased funding be committed to this important issue.  相似文献   
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A freshwater gastropod, Pachycheilus glaphyrus, responsible for unusual erosion in limestone has been located in southern British Honduras where it is abundant in streams flowing through areas of karst topography. These snails ingest algae that proliferate in solution grooves formed at the fluctuating air-water interface. Rasping action of the radula results in deepening of these grooves and appears to improve the algal habitat.  相似文献   
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The reproductive organs of some plants self-heat, release scent, and attract pollinators. The relations among these processes are not well understood, especially in the more ancient, nonflowering gymnosperm lineages. We describe the influence of plant volatiles in an obligate pollination mutualism between an Australian Macrozamia cycad (a gymnosperm with male and female individuals) and its specialist thrips pollinator, Cycadothrips chadwicki. Pollen-laden thrips leave male cycad cones en masse during the daily thermogenic phase, when cone temperatures and volatile emissions increase dramatically and thrips are repelled. As thermogenesis declines, total volatile emissions diminish and cones attract thrips, resulting in pollination of female cones. Behavioral and electrophysiological tests on thrips reveal that variations in b-myrcene and ocimene emissions by male and female cones are sufficient to explain the observed sequential thrips' repellence (push) and attraction (pull). These dynamic interactions represent complex adaptations that enhance the likelihood of pollination and may reflect an intermediate state in the evolution of biotic pollination.  相似文献   
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Because of its requirement for signaling by multiple cytokines, Janus kinase 3 (JAK3) is an excellent target for clinical immunosuppression. We report the development of a specific, orally active inhibitor of JAK3, CP-690,550, that significantly prolonged survival in a murine model of heart transplantation and in cynomolgus monkeys receiving kidney transplants. CP-690,550 treatment was not associated with hypertension, hyperlipidemia, or lymphoproliferative disease. On the basis of these preclinical results, we believe JAK3 blockade by CP-690,550 has potential for therapeutically desirable immunosuppression in human organ transplantation and in other clinical settings.  相似文献   
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