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Medical education is increasingly laying emphasis on a curriculum based on cognitive, psychomotor, and affective domains of learning which were originally proposed nearly 50 years ago. These reforms are framed around best standards of care, error management and patient safety, patient autonomy, and resource allocation. There is a worldwide shift in the method of medical education towards experiential (‘hands-on’) medical learning; however, applying this concept to real patients is less acceptable to society and is subject to legal and ethical issues.  相似文献   
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The authors prospectively studied 20 fetuses with mild dilatation of the lateral cerebral ventricles but no other detectable central nervous system abnormality. One case (5%) occurred in a diabetic pregnancy, and three (15%) involved twin pregnancies. Fifteen (75%) fetuses were male, and one (5%) had trisomy 21. Postnatal follow-up at 15-31 months showed a normal outcome in eight cases (40%), an uncertain prognosis in four cases (20%), and death in eight cases (40%). Serial antenatal sonograms were obtained in 17 cases. Among the eight cases with a normal outcome, seven demonstrated no additional sonographic abnormalities and six showed resolution of the ventricular dilatation antenatally. Conversely, all 12 fetuses with demise or an uncertain prognosis demonstrated additional sonographic abnormalities, and six showed stable or progressive ventricular dilatation on follow-up sonograms. Since mild idiopathic lateral ventricular dilatation has a widely variable prognosis, antenatal detection of this finding warrants search for additional findings and follow-up sonography.  相似文献   
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Whole cell patch-clamp recordings were obtained from dissociated mouse lumbar dorsal root ganglion (DRG) neurons. Recordings were made from control neurons and neurons axotomized by transection of the corresponding spinal nerve 1-2 days prior to dissociation. Medium to large muscle and cutaneous afferent neurons were identified by retrograde transport of True Blue or Fluoro-Gold injected into the corresponding peripheral tissue. Action potentials were classified as non-inflected spikes (A(0)) and inflected spikes (A(inf)). High-frequency, low-amplitude subthreshold membrane potential oscillations were observed in 8% of control A(0) neurons, but their incidence increased to 31% in the nerve injury group. Fifty percent of axotomized muscle afferent A(0) cells displayed oscillations, while 26% of axotomized cutaneous afferents exhibited oscillations. Lower-frequency oscillations were also observed in a small fraction (4%) of A(inf) neurons on strong depolarization. Their numbers were increased after the nerve injury, but the difference was not statistically significant. The oscillations often triggered burst firing in distinct patterns of action potential activity. These results indicate that injury-induced membrane oscillations of DRG neurons, previously observed in whole DRG of rats, are present in dissociated DRG neurons of the adult mouse. Moreover, these observations indicate that both muscle and cutaneous afferents in the A(beta) size range give rise to injury-induced membrane oscillations, with muscle afferents being more prone to develop oscillations.  相似文献   
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Background

Health care workers (HCWs) in Armed Forces are immunised against Hepatitis B virus (HBV), however they are not subjected to anti-HBs (antibody to Hepatitis B surface antigen) assessment after primary vaccination. The present study was undertaken to determine the protection offered by HBV vaccine in HCW.

Methods

Cross-sectional study was carried out at tertiary care hospital. A total 146 HBV vaccine compliant HCW were evaluated for quantitative anti-HBs by enzyme immune assay.

Result

129 (88.4%) subjects had protective levels of anti-HBs. Higher age at vaccination was an important risk factor in low vaccine response. Decline in anti-HBs with time was evident. Anti-HBs levels were more than 10mIU/ml in subjects even after 11 years of primary vaccination. There was no difference in protection in booster and non booster groups.

Conclusion

Age is the most important factor in HBV vaccine response. Booster dose of HBV vaccine is not necessary in healthy HCW for atleast ten years after primary vaccination. The study recommends early primary vaccination of HCW and ‘initial’ anti-HBs assay for confirmation of vaccine response.Key Words: Anti-Hepatitis B surface antigen, Health care workers, Hepatitis B virus vaccine  相似文献   
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BACKGROUND: Ethnic/racial minorities experience poorer outcomes from lung cancer than non-Hispanic whites. Higher hospital procedure volume is associated with better survival from lung resection for lung cancer. OBJECTIVES: We examined whether (1) ethnic/racial minorities are more likely to obtain lung resections at lower volume hospitals, (2) ethnicity/race is associated with inpatient mortality, (3) hospital volume mediates this association, and (4) hospital selection is mediated by racial/ethnic segregation, differences in insurance coverage, or limited hospital choice. METHODS: Six years of data from the Nationwide Inpatient Sample (NIS 1998-2003, unweighted n = 50,245, weighted n = 129,506) were used in multivariate models controlling for sociodemographic factors, case complexity, and hospital characteristics. Additional analyses were conducted using the Area Resource File, which provided data on ethnic density and number of surgical hospitals in the hospital region. RESULTS: Blacks/African Americans (odds ratio [OR] = 0.45; 0.34-0.58) and Latinos (OR = 0.44; 0.32-0.63) had lower odds of obtaining lung resection at a high-volume hospital than non-Hispanic whites. Blacks/African Americans (OR = 1.30; 1.01-1.67), Latinos (OR = 1.41; 1.02-1.94), and other racial/ethnic minorities (OR = 1.46; 1.04-2.06) also had higher odds of dying in hospital, but this association was statistically nonsignificant after controlling for hospital volume. Hospital location was not associated with lung resection procedure volume, nor did location mediate the association between ethnicity/race and hospital volume. CONCLUSIONS: Ethnic/racial minorities are obtaining lung resection in lower volume hospitals and are more likely to die in hospital. Hospital volume is associated with higher mortality, but health insurance, segregation, and number of surgical hospitals within a county do not account for observed disparities.  相似文献   
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BACKGROUND: Project STRIDE is a 4-year randomized controlled trial comparing two computer-based expert system guided intervention delivery channels (phone vs. print) for physical activity adoption and short-term maintenance among previously sedentary adults. METHODS: Sedentary adults (n=239) were randomized to one of the following (1) telephone-based, individualized motivationally-tailored feedback; (2) print-based, individualized motivationally-tailored feedback; (3) contact-control delayed treatment group (received intervention after 12 months as control). This paper: (1) outlines the study design, rationale, and participant sample; and (2) describes relationships between baseline variables to better understand their influence on the efficacy of the intervention. RESULTS: Participants averaged 19.8+/-25.0 min of physical activity/week that was at least of moderate intensity, with no group differences. The average estimated VO(2) at 85% of maximum heart rate was 25.6 ml/kg/min. Body fat was 34.1% for women and 23.2% for men and the BMI of the sample averaged 28.5 kg/m(2). CONCLUSIONS: Project STRIDE examines non face-to-face approaches for promoting physical activity behavior. It has unique features including a direct comparison of an expert system guided intervention delivered via phone or print. Future analyses will examine the cost-effectiveness of the interventions and this will likely yield important information for policy-makers.  相似文献   
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