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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   
104.
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   
105.
The efflux transporter, the breast cancer resistance protein (BCRP), is most abundantly expressed in the apical membrane of the placental syncytiotrophoblasts, indicating that it could play an important role in protecting the fetus by limiting xenobiotic/drug penetration across the placental barrier. In the present study, we examined whether Bcrp1, the murine homolog of human BCRP, limits fetal distribution of the model BCRP/Bcrp1 substrate, nitrofurantoin (NFT), in the pregnant mouse. NFT was administered i.v. to FVB wild-type and Bcrp1(-/-) pregnant mice. The maternal plasma samples and fetuses were collected at various times (5-60 min) after drug administration. The NFT concentrations in the maternal plasma samples and homogenates of fetal tissues were determined by a high-performance liquid chromatography/UV assay. Although the maternal plasma area under the concentration-time curve (AUC) of NFT in the Bcrp1(-/-) pregnant mice (97.4 +/- 10.0 microg . min/ml plasma) was only slightly (but significantly) higher than that in the wild-type pregnant mice (78.4 +/- 6.0 microg . min/ml plasma), the fetal AUC of NFT in the Bcrp1(-/-) pregnant mice (1493.0 +/- 235.3 ng . min/g of fetus) was approximately 5 times greater than that in the wild-type pregnant mice (298.6 +/- 77.4 ng . min/g of fetus). These results clearly suggest that Bcrp1 significantly limits fetal distribution of NFT in the pregnant mouse, but has only a minor effect on the systemic clearance of the drug.  相似文献   
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Pharmacokinetics of acyclovir in the term human pregnancy and neonate.   总被引:6,自引:0,他引:6  
Concern about neonatal herpes often leads to cesarean delivery of infants in women with a history of genital herpes. The antiviral drug acyclovir has been used effectively to suppress genital herpes simplex virus recurrences in nonpregnant adults. Its administration to pregnant women with recurrent genital herpes may reduce herpes simplex virus recurrences and thus may decrease the cesarean section rate among this population. To study the pharmacokinetics, safety, and patient tolerance of suppressive oral acyclovir, either 200 mg (n = 7) or 400 mg (n = 8) was administered orally every 8 hours to pregnant women with a history of recurrent herpes simplex virus, from 38 weeks' gestation until delivery. The mean +/- SD plasma levels for the 200 and 400 mg groups, respectively, were: first dose peak, 1.7 +/- 0.6 and 2.3 +/- 1.0 mumol/L; steady-state trough, 0.7 +/- 0.3 and 0.8 +/- 0.6 mumol/L; steady-state peak, 1.9 +/- 1.0 and 3.3 +/- 1.0 mumol/L. In late gestation maternal acyclovir pharmacokinetics were similar to those of nonpregnant adults from other studies. Acyclovir was concentrated in the amniotic fluid; however, there was no accumulation in the fetus (mean maternal/infant plasma ratio at delivery was 1.3). Acyclovir was well tolerated, and no toxicity was seen in the mothers or infants. The administration of acyclovir, 400 mg every 8 hours, appears appropriate for use in an efficacy and safety study regarding suppression of herpes simplex virus recurrences during the last weeks of pregnancy.  相似文献   
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Hispanics have been disproportionately impacted by HIV/AIDS. Although HIV risk is significantly elevated among severely mentally ill persons (SMI), the risk of infection appears to be even greater among those SMI who are Hispanic, reflecting the increased risk of HIV among Hispanics. We report on findings from the first 41 participants in a qualitative study examining the context of HIV risk and risk reduction strategies among severely mentally ill Puerto Rican women residents in northeastern Ohio. Individuals participated in a baseline interview, two follow-up interviews, and up to 100 hours of shadowing. Interviews and shadowing activities were recorded and analyzed using a grounded theory. The majority of individuals reported using identification with a religious faith. A large proportion of the participants reported that their religious or spiritual beliefs were critical to their coping, had influenced them to reduce risk, and/or provided them with needed social support. Several participants also reported having experienced rejection from their faith communities. The emphasis on spirituality among Puerto Rican SMI is consistent with previous research demonstrating the importance of spirituality in the Hispanic culture and reliance on spiritual beliefs as a mean of coping among SMI. Our results support the incorporation of spiritual beliefs into secular HIV prevention efforts. Loue is with the Department of Epidemiology and Biostatistics, Center for Minority Public Health, School of Medicine, Case Western Reserve University, Cleveland, OH, USA; Sajatovic is with the Department of Psychiatry, School of Medicine, Case Western Reserve University, Cleveland, OH, USA.  相似文献   
110.
CONTEXT: Recent bioterrorism attacks have highlighted the critical need for health care organizations to prepare for future threats. Yet, relatively little attention has been paid to the mental health needs of rural communities in the wake of such events. A critical aspect of bioterrorism is emphasis on generating fear and uncertainty, thereby contributing to increased needs for mental health care, particularly for posttraumatic stress disorder, which has been estimated to occur in 28% of terrorism survivors. PURPOSE: Prior experience with natural disasters suggests that first responders typically focus on immediate medical trauma or injury, leaving rural communities to struggle with the burden of unmet mental health needs both in the immediate aftermath and over the longer term. The purpose of the present article is to draw attention to the greater need to educate rural primary care providers who will be the frontline providers of mental health services following bioterrorism, given the limited availability of tertiary mental health care in rural communities. METHODS: We reviewed the literature related to bioterrorism events and mental health with an emphasis on rural communities. FINDINGS AND CONCLUSIONS: Public health agencies should work with rural primary care providers and mental health professionals to develop educational interventions focused on posttraumatic stress disorder and other mental disorders, as well as algorithms for assessment, referral, and treatment of post-event psychological disorders and somatic complaints to ensure the availability, continuity, and delivery of quality mental health care for rural residents following bioterrorism and other public health emergencies.  相似文献   
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