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1.
With increasing life span of patients with CF, more women with CF are becoming pregnant and others are seeking information about the risks involved during pregnancy and delivery. A striking limitation of the available information is the lack of large prospective studies of pregnant patients with CF matched for age and disease severity compared with their non-pregnant cohorts. A study investigating the effect of pregnancy on morbidity and mortality is being completed by the Cystic Fibrosis Foundation. We recommend that all women with CF be offered contraceptive measures and counseling on the maternal and fetal risks of pregnancy, including the genetic risks for the child. The issue of who will raise the child in the event of subsequent morbidity or maternal mortality should ideally be prospectively discussed. 相似文献
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PB Imrey LA Jackson PH Ludwinski AC England GA Fella BC Fox LB Isdale MW Reeves JD Wenger 《Canadian Metallurgical Quarterly》1996,143(6):624-630
Between February 1991 and April 1992, eight undergraduates at a US residential university and one at a nearby 2-year college contracted serogroup C meningococcal disease. A case-control investigation with 20 controls per case, oropharyngeal carriage surveys, and multilocus enzyme electrophoresis (MEE) of serogroup C isolates were used to identify factors contributing to the outbreak. All eight sterile-site isolates from cases were closely related by MEE and were similar (though not identical) to the strain associated with the 1991-1992 epidemic of meningococcal disease in eastern Canada. Disease was associated with cigarette smoking (p = 0.012), recent patronage of campus-area bars (p = 0.034), estimated amount of time spent in campus-area bars (p = 0.0003), and, especially, recent patronage of one specific bar, bar A (p = 0.0006; odds ratio = 23.1, 95% confidence interval 3.0-571.5). In carriage surveys, 1,528 throat cultures taken from (primarily student) noncases yielded only five (0.3%) strains that were identical by MEE to those from cases. Two of these were found among 22 cultures obtained from bar A employees in spring 1992. Some cases in this outbreak may have followed transmission of the epidemic strain in bar A. Campus bar environments may facilitate the spread of meningococcal disease among teenagers and young adults. 相似文献
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Z Chen A Spies R Hein X Zhou BC Thomas ML Richter P Gegenheimer 《Canadian Metallurgical Quarterly》1995,270(29):17124-17132
F1F0-ATP synthases utilize protein conformational changes induced by a transmembrane proton gradient to synthesize ATP. The allosteric cooperativity of these multisubunit enzymes presumably requires numerous protein-protein interactions within the enzyme complex. To correlate known in vitro changes in subunit structure with in vivo allosteric interactions, we introduced the beta subunit of spinach chloroplast coupling factor 1 ATP into a bacterial F1 ATP synthase. A cloned atpB gene, encoding the complete chloroplast beta subunit, complemented a chromosomal deletion of the cognate uncD gene in Escherichia coli and was incorporated into a functional hybrid F1 ATP synthase. The cysteine residue at position 63 in chloroplast beta is known to be located at the interface between alpha and beta subunits and to be conformationally coupled, in vitro, to the nucleotide binding site > 40 A away. Enlarging the side chain of chloroplast coupling factor 1 beta residue 63 from Cys to Trp blocked ATP synthesis in vivo without significantly impairing ATPase activity or ADP binding in vitro. The in vivo coupling of nucleotide binding at catalytic sites to transmembrane proton movement may thus involve an interaction, via conformational changes, between the amino-terminal domains of the alpha and beta subunits. 相似文献
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Health-related quality of life (HRQOL) is an important dimension in assessing health care. Several methodologic considerations are related to the manner in which these data are obtained in children. Few multidimensional generic measures of quality of life (QOL) have been developed for children and adolescents. Most published research concerns the development of tools to be used in a disease-specific manner for clinical trials. Although several authors point out numerous advantages in assessing HRQOL in clinical practice, several barriers must be overcome for this to occur. In the current era of economic restraint, HRQOL measures must be integrated into pharmaco-economic analyses to assess fully the impact of a drug on health care resources and outcomes. 相似文献
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