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Medical students usually initially learn vaginal examination (VE) by examining consenting anaesthetised women. To assess their experience of this practice, a questionnaire was distributed to all 66 fifth-year students at the Wellington School of Medicine in 2005—53 students responded. Although 184 women were available to approach for consent, only 141 were approached—students claimed insufficient time as their major difficulty. All male students discussed consent with women only in the 2 hours preoperatively, whereas nine (28%) of the female students sought consent earlier on the day or the day before. Of the 114 women asked, 97 gave written consent, but the VE was conducted in only 76 women mostly because the supervising gynaecologist claimed time constraints or was uninterested. Four other women were examined when consent was uncertain and two without consent. All but one of the students considered the experience educationally valuable. Eleven responding students did not perform a VE, and if the 13 nonresponders also did not, more than one-third of students lack this educational opportunity prior to their final year. In conclusion, some students require more commitment to seeking consent, and some gynaecologists may need to better facilitate this learning opportunity so that the consent agreed with the woman and student is more often respected.  相似文献   
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Porphyria cutanea tarda (PCT) arises from decreased hepatic activity of uroporphyrinogen decarboxylase (UROD). Both genetic and environmental factors interplay in the precipitation of clinically overt PCT, but these factors may vary between different geographic areas. Decreased activity of UROD in erythrocytes was used to identify patients with UROD mutations among a group of 130 Spanish PCT patients. Nineteen patients (14.6%) were found to harbor a mutation in the UROD gene. Eight mutations were novel: M1I, 5del10, A22V, D79N, F84I, Q116X, T141I and Y182C. Five others were previously described: F46L, V134Q, R142Q, P150L and E218G. The new missense mutations and P150L were expressed in Escherichia coli. D79N and P150L resulted in proteins that were localized to inclusion bodies. The other mutations produced recombinant proteins that were purified and showed reduced activity (range: 2.3–73.2% of wild type). These single amino acid changes were predicted to produce complex structural alterations and/or reduced stability of the enzyme. Screening of relatives of the probands showed that 37.5% of mutation carriers demonstrated increased urinary porphyrins. This study emphasizes the role of UROD mutations as a strong risk factor for PCT even in areas where environmental factors (hepatitis C virus) have been shown to be highly associated with the disease.  相似文献   
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BACKGROUND: Breast cancer care, such as utilization of screening procedures and types of treatment received, varies substantially by geographic region of the United States. However, little is known about variations in survival with breast cancer. METHODS: We examined breast cancer incidence, survival, and mortality in the 66 health service areas covered by the Surveillance, Epidemiology, and End Results (SEER) program for women aged 65 and older at diagnosis. Incidence and survival data were derived from SEER, while breast cancer mortality data were from Vital Statistics data. RESULTS: There was considerable variation in breast cancer survival among the 66 health service areas (chi2 = 202.7, p <.0001). There was also significant variation in incidence and mortality from breast cancer. In a partial correlation weighted for the size of the health service area, both incidence (r =.812) and percent 5-year survival (r = -.587) correlate with mortality. In a Poisson regression analysis, the combination of variation in incidence and variation in survival explains 90.9% of the variation in mortality. CONCLUSIONS: There is considerable geographic variation in survival from breast cancer among older women, and this contributes to variation in breast cancer mortality. Geographic variations in breast cancer mortality should diminish as the quality of breast cancer care becomes more standardized.  相似文献   
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