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21.
The phenotypic variance-covariance matrix (P) describes the multivariate distribution of a population in phenotypic space, providing direct insight into the appropriateness of measured traits within the context of multicollinearity (i.e., do they describe any significant variance that is independent of other traits), and whether trait covariances restrict the combinations of phenotypes available to selection. Given the importance of P, it is therefore surprising that phenotypic covariances are seldom jointly analyzed and that the dimensionality of P has rarely been investigated in a rigorous statistical framework. Here, we used a repeated measures approach to quantify P separately for populations of four cricket species using seven acoustic signaling traits thought to enhance mate attraction. P was of full or almost full dimensionality in all four species, indicating that all traits conveyed some information that was independent of the other traits, and that phenotypic trait covariances do not constrain the combinations of signaling traits available to selection. P also differed significantly among species, although the dominant axis of phenotypic variation (p(max)) was largely shared among three of the species (Acheta domesticus, Gryllus assimilis, G. texensis), but different in the fourth (G. veletis). In G. veletis and A. domesticus, but not G. assimilis and G. texensis, p(max) was correlated with body size, while p(max) was not correlated with residual mass (a condition measure) in any of the species. This study reveals the importance of jointly analyzing phenotypic traits. 相似文献
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A major challenge of medical anthropology is to assess howbiomedicine, as a vaguely-defined set of diverse texts,technologies, and practitioners, shapes the experience of selfand body. Through narrative analyses of in-depth, semi-structuredinterviews with 158 pregnant women in southern California, thispaper explores how the culture of biomedicine, encounteredformally at prenatal care check-ups and informally throughdiverse media, influences pregnant women's perceptions ofappropriate prenatal behavior. In the spirit of recent socialscientific work that draws on and challenges Foucauldian insightsto explore social relations in medicine, we posit a spectrum ofcompliance and resistance to biomedical norms upon whichindividual prenatal practices are assessed. We suggest thatpregnancy is, above all, characterized by a split subjectivity inwhich women straddle the authoritative and the subjugated, theobjective and the subjective, and the haptic as well as theoptic, in telling and often strategic ways. In so doing, weidentify the intersection between the disciplinary practices ofbiomedicine and the practices of pregnant women as a means offurnishing more fruitful insights into the oft-used term ``power'and its roles in constituting social relations in medicine. 相似文献
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The oviduct from laying quail were used to investigate mechanisms of trace mineral secretion and the possible role of metallothionein in this process. Secretion of zinc occurred maximally at pH 5.4, which is close to the normal pH of the oviduct. Secretion occurred to a much greater extent in the isthmus and shell gland than in the magnum, the major protein-secretory section of the oviduct. Intraperitoneal administration of cadmium resulted in a marked reduction in Zn secretion from the oviduct of laying quail. This effect could not be correlated with metallothionein since metallothionein could not be detected in any section of the oviduct in control or Cd-induced quail. Small-molecular-weight metal-binding ligands were present in the isthmus and shell gland, which may play a role in trace mineral mobilization. Histological evaluation by light and elelctron microscopy show that Zn is transported from the smooth muscle cells through the connective tissue matrix in the extracellular space to the epithelial goblet cells. Presumably, Zn and other trace minerals are secreted from the secretory goblet cells into the egg. 相似文献
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Five patients seen during a two-month period who developed untoward systemic reactions following high dose intravenous administration of nafcillin are described. Recovery was complete upon discontinuation of the drug. The clustering of these cases and the high incidence (5 of 5) of side effects are highly unusual, and suggest that the frequency of nafcillin reactions might be higher than previously suspected. 相似文献
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Although it is an intrinsic part of all medical practice forensic medicine often is either unrecognized as such or is consciously or subconsciously evaded. The failure to apply some rather basic and simple forensic principles that only the physician is capable of doing may result in problems to the patient ranging from frustration to near catastrophe. For physicians who are reasonably well equipped to understand the legal system, the successful conclusion of a legal case, including, sometimes, an appearance in court, can be stimulating and interesting. 相似文献
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M P Skupski M Booker A Farmer M Harpold W Huang J Inman D Kiphart C Kodira S Root F Schilkey J Schwertfeger A Siepel D Stamper N Thayer R Thompson J Wortman J J Zhuang C Harger 《Nucleic acids research》1999,27(1):35-38
During 1998 the primary focus of the Genome Sequence DataBase (GSDB; http://www.ncgr.org/gsdb ) located at the National Center for Genome Resources (NCGR) has been to improve data quality, improve data collections, and provide new methods and tools to access and analyze data. Data quality has been improved by extensive curation of certain data fields necessary for maintaining data collections and for using certain tools. Data quality has also been increased by improvements to the suite of programs that import data from the International Nucleotide Sequence Database Collaboration (IC). The Sequence Tag Alignment and Consensus Knowledgebase (STACK), a database of human expressed gene sequences developed by the South African National Bioinformatics Institute (SANBI), became available within the last year, allowing public access to this valuable resource of expressed sequences. Data access was improved by the addition of the Sequence Viewer, a platform-independent graphical viewer for GSDB sequence data. This tool has also been integrated with other searching and data retrieval tools. A BLAST homology search service was also made available, allowing researchers to search all of the data, including the unique data, that are available from GSDB. These improvements are designed to make GSDB more accessible to users, extend the rich searching capability already present in GSDB, and to facilitate the transition to an integrated system containing many different types of biological data. 相似文献