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991.
992.
Residential mobility during pregnancy 总被引:1,自引:0,他引:1
In epidemiological studies of environmental exposures and adverse pregnancy outcomes, maternal residence at delivery is often used to assign an exposure level, based on routinely collected data. In order to examine the potential for exposure misclassification due to residential mobility, we examined maternal mobility according to changes in residence overall, as well as changes in municipality and county. The potential for mobility to be related to pregnancy outcomes was considered by examining the relationship between mobility and risk factors commonly included in investigations of adverse pregnancy outcomes. Previously collected data were studied from 398 population-based control subjects from a case-control study of stillbirths. We compared demographic, lifestyle, medical, pregnancy and environmental factors of women who moved during pregnancy with those who did not. Bivariable and multivariable log binomial regressions were used to identify risk factors that were associated with mobility during pregnancy. Twelve per cent of subjects moved at least once during their pregnancy. Among women who moved, the majority (62%) moved within the same municipality. In bivariable analyses, we found that low family income, lower maternal age, unmarried status and tobacco use were associated with an increased likelihood of moving during pregnancy, whereas women who used folic acid before conception and who had a higher prepregnancy body mass index (BMI) were less likely to move during pregnancy. In multivariable analyses, only family income, age and prepregnancy BMI were independently predictive of mobility. These results indicate that in studies using maternal residence at delivery to assign environmental exposures, mobility during pregnancy is likely to be prevalent enough to introduce exposure misclassification. The potential for differential exposure misclassification should be considered should any of the risk factors for moving identified by this study also be risk factors for the outcome under study. 相似文献
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994.
The large number of active combination chemotherapy regimens for the treatment of gastrointestinal cancers has led to the need for better information to guide the "standard" treatment for each patient. In an attempt to individualize therapy, pharmacogenomics evaluates the hereditary basis for interindividual differences in drug response. This report will focus on the results of studies assessing the effects of polymorphisms in drug-metabolizing enzymes and drug targets on the toxicity and response to chemotherapy drugs commonly used to treat gastrointestinal malignancies. 相似文献
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During infection of insect cells with Autographa californica nucleopolyhedrovirus (AcMNPV), the very late protein P10 forms large fibrillar structures in the cytoplasm and nuclei of infected cells. In this study we have used confocal microscopy in association with a novel P10 antiserum to localise and study P10 in virus-infected cells. P10 was shown to be a component of tubular-like structures that spiralled throughout the cytoplasm and nucleus of AcMNPV-infected cells. These structures were observed to colocalise partly with cortical microtubules. When microtubules were depolymerised with the drug nocodazole, P10 tubules failed to form and the protein appeared concentrated in cytoplasmic foci. For the first time, we provide direct evidence using both antibody pulldown and yeast two-hybrid experiments for the interaction of P10 with host-cell tubulin. It is suggested that this interaction may be a critical factor in AcMNPV-induced cell lysis. 相似文献
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Analysis of an IS2404-based nested PCR for diagnosis of Buruli ulcer disease in regions of Ghana where the disease is endemic 下载免费PDF全文
Stienstra Y van der Werf TS Guarner J Raghunathan PL Spotts Whitney EA van der Graaf WT Asamoa K Tappero JW Ashford DA King CH 《Journal of clinical microbiology》2003,41(2):794-797
Mycobacterium ulcerans causes Buruli ulcer disease (BUD), an ulcerative skin disease emerging mainly in West Africa. Laboratory confirmation of BUD is complicated as no "gold standard" for diagnosis exists. A nested primer PCR based on IS2404 has shown promise as a diagnostic assay. We evaluated the IS2404-based PCR to detect M. ulcerans DNA in tissue specimens from 143 BUD patients diagnosed according to the World Health Organization BUD clinical case definition in Ghana. Comparisons were made with culture and histopathology results. Variables influencing detection rate tested in this PCR protocol included the amount of tissue used and the stage of disease. The nested PCR was repeated on DNA extracted from a different part of the same biopsy specimen of 21 culture-positive samples. Of all 143 specimens, 107 (74.8%; 95% confidence interval, 68 to 82%) showed the presence of M. ulcerans DNA by PCR. Of the 78 histology-confirmed BUD patient samples, 64 (83%) were PCR positive. Detection rates were influenced neither by the amount of tissue processed for PCR nor by the stage of disease (preulcerative or ulcerative). Taken together, the two nested PCR tests on the subset of 21 culture-positive samples were able to detect M. ulcerans DNA in all 21 culture-confirmed patients. For future studies, small tissue samples, e.g., punch biopsy samples, might be sufficient for case confirmation. 相似文献
1000.
Allen JE King MR Farrar DF Miller DS Schorge JO 《American journal of obstetrics and gynecology》2003,188(5):1151-1153
OBJECTIVE: The purpose of this study was to determine compliance with postmolar pregnancy surveillance in our indigent population. STUDY DESIGN: Data for all women who were diagnosed with molar pregnancy from January 1996 through December 2000 were entered prospectively into a database. After remission, postmolar pregnancy surveillance was continued for 6 months. Patients whose condition required chemotherapy for gestational trophoblastic tumor had 12 months of follow-up. Medical records were reviewed. RESULTS: Molar pregnancies occurred in 121 women: 103 Hispanic women (85%), 12 African American women (10%), and 6 white women (5%). Eighty-two women (68%) achieved remission without chemotherapy; 23 women (19%) were lost to follow-up without achieving remission, and 16 women (13%) had gestational trophoblastic tumor. Fifty-six Hispanic women (54%) completed postmolar pregnancy surveillance, compared with two African American women (11%, P <.01). Hispanic patients who were fluent in Spanish only were more likely to complete follow-up than bilingual Hispanic patients (62% vs 41%, P <.01). CONCLUSION: Hispanic women who were fluent in Spanish only were most likely to complete the recommended postmolar human chorionic gonadotropin surveillance. 相似文献