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The complete sequencing and annotation of the 181.7-kb Bacillus anthracis virulence plasmid pXO1 predicted 143 genes but could only assign putative functions to 45. Hybridization assays, PCR amplification, and DNA sequencing were used to determine whether pXO1 open reading frame (ORF) sequences were present in other bacilli and more distantly related bacterial genera. Eighteen Bacillus species isolates and four other bacterial species were tested for the presence of 106 pXO1 ORFs. Three ORFs were conserved in most of the bacteria tested. Many of the pXO1 ORFs were detected in closely related Bacillus species, and some were detected only in B. anthracis isolates. Three isolates, Bacillus cereus D-17, B. cereus 43881, and Bacillus thuringiensis 33679, contained sequences that were similar to more than one-half of the pXO1 ORF sequences examined. The majority of the DNA fragments that were amplified by PCR from these organisms had DNA sequences between 80 and 98% similar to that of pXO1. Pulsed-field gel electrophoresis revealed large potential plasmids present in both B. cereus 43881 (341 kb) and B. thuringiensis ATCC 33679 (327 kb) that hybridized with a DNA probe composed of six pXO1 ORFs.  相似文献   
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Overweight patients report weight discrimination in health care settings and subsequent avoidance of routine preventive health care. The purpose of this study was to examine implicit and explicit attitudes about weight among a large group of medical doctors (MDs) to determine the pervasiveness of negative attitudes about weight among MDs. Test-takers voluntarily accessed a public Web site, known as Project Implicit®, and opted to complete the Weight Implicit Association Test (IAT) (N = 359,261). A sub-sample identified their highest level of education as MD (N = 2,284). Among the MDs, 55% were female, 78% reported their race as white, and 62% had a normal range BMI. This large sample of test-takers showed strong implicit anti-fat bias (Cohen’s d = 1.0). MDs, on average, also showed strong implicit anti-fat bias (Cohen’s d = 0.93). All test-takers and the MD sub-sample reported a strong preference for thin people rather than fat people or a strong explicit anti-fat bias. We conclude that strong implicit and explicit anti-fat bias is as pervasive among MDs as it is among the general public. An important area for future research is to investigate the association between providers’ implicit and explicit attitudes about weight, patient reports of weight discrimination in health care, and quality of care delivered to overweight patients.  相似文献   
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An explicit general criterion for stability-instability at fixation states is provided when the leading eigenvalue of the gradient matrix is one. Several applications in population genetics are presented including cases of familial selection of dominant and recessive genes, models of preferential mating, incompatibility systems, and effects of migration and population structure.  相似文献   
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Despite the availability of rubella vaccine the incidence of the congenital rubella syndrome has been increasing in certain regions of Canada. Perhaps this is not surprising in view of the known irregular cyclic activity of rubella virus in a community and the fact that the percentage of seropositive women of childbearing age has not changed appreciable since the vaccine was introduced. Clearly vaccine is not being administered to sufficient numbers of women at risk. Until a much higher percentage of women of childbearing age possess rubella antibody, the costly problem of congenital rubella syndrome is likely to be with us. Common rubella problems relate to four categories: the exposed pregnant woman, laboratory diagnosis, the infant with suspected congenital rubella and the vaccine. One of the most common questions about the vaccine is the following: Can recently vaccinated individuals disseminate vaccine and infect seronegative contact? The answer is No.  相似文献   
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Bioprocess and Biosystems Engineering - The integrated fixed-film activated sludge (IFAS) process is being increasingly used to enhance nitrogen removal for former activated sludge systems. The aim...  相似文献   
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