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61.
This study investigated the attitudes of medical students towards psychiatry, both as a subject on the medical curriculum and as a career choice. Three separate questionnaires previously validated on medical student populations were administered prior to and immediately following an 8-week clinical training programme. The results indicate that the perception of psychiatry was positive prior to clerkship and became even more so on completion of training. On completion of the clerkship, there was a rise in the proportion of students who indicated that they might choose a career in psychiatry. Attitudes toward psychiatry correlated positively with the psychiatry examination results. Those that intended to specialise in psychiatry achieved significantly higher examination scores in the psychiatry examination.  相似文献   
62.
Objectives. The management of intractable urinary incontinence in the patient with cloacal or bladder exstrophy/epispadias, failed bladder neck plasty, or failed augmentation cystoplasty remains a surgical challenge. The myofascial wrap, a modification of the rectus fascial wrap, was developed to treat intractable urinary incontinence due to sphincteric incompetence in these problematic cases. A full-thickness, vascularized pedicle of anterior rectus sheath, rectus abdominis muscle, and posterior rector sheath is incorporated into a bladder neck wrap to provide support, mucosal coaptation, and active muscular tone.Methods. Eight patients (5 females and 3 males) with total urinary incontinence due to sphincteric incompetence underwent the myofascial wrap. Urinary tract pathology included cloacal exstrophy (2), female epispadias (2), classic bladder exstrophy (1), male epispadias (1), myelomeningocele (1), and a pelvic tumor (1). The procedure is performed by harvesting a full-thickness strip of pedicled rectus muscle along with the anterior and posterior fascial sheaths. The strip is passed underneath and then over the bladder neck in a near 360° wrap. The free end of the wrap is anchored into the pubic bone in an ipsilateral subperiosteal pouch.Results. Six of the 8 patients are completely continent, and 2 patients void spontaneously without the need for catheterization.Conclusions. The myofascial wrap provides support, mucosal coaptation, and muscular tone to an incompetent sphincter and bladder neck. Favorable results in a very difficult population of pediatric patients warrant its continued use.  相似文献   
63.
The feasibility of a centralized menu and the effectiveness of an "offer vs. serve" option within a self-serve, choice menu lunch program at the elementary school level were determined. Student trays (no. = 370/day) were visually evaluated for foods chosen and consumed. The same 1-week menu was served at two urban Southern schools. One represented a high-poverty-area, all-black-student school and the other represented a middle-income-area school with a white to black student ratio of 3:1. Students were able to choose the required USDA minimal number of three foods, and 66% of the foods selected were similar at the two schools, demonstrating that a centralized menu was feasible. Three-fourths of the students were able to choose more than 75% of one-third of the RDA for all nutrients except pyridoxine and ascorbic acid at both schools and iron at the high-poverty school. Twenty-five percent or more of the students did not consume 75% of one-third the Recommended Dietary Allowance for thiamin, vitamin B-6, ascorbic acid, iron, and magnesium at either school or of niacin and vitamin A at the middle-income school. Overall plate waste was 12.9%, with younger children wasting more food than older children and more waste in the middle-income than the high-poverty school. In general, the "offer vs. serve" was an effective option.  相似文献   
64.
Impaired conditioned taste aversion learning in APP transgenic mice   总被引:8,自引:0,他引:8  
Cognition in transgenic mouse models of Alzheimer's disease (AD) has been predominantly characterized in explicit spatial orientation tasks. However, dementia in AD encompasses also implicit memory systems. In the present study a line of transgenic mice (TgCRND8) encoding a double mutated allele of the human amyloid precursor protein (APP) genes was evaluated in an implicit associative learning task of conditioned taste aversion (CTA). CTA is a form of Pavlovian classical conditioning, in which a mouse learns to avoid a novel taste of saccharine (conditioned stimulus) paired with an experimentally induced (systemic injection of lithium chloride) nausea (unconditioned stimulus). In contrast to conditioned non-Tg mice, TgCRND8 APP mice developed weaker aversion against saccharine and quickly increased its consumption in repeated tests. These results indicate that TgCRND8 mice show a significant impairment not only in explicit spatial memory, as has been previously shown [Nature 408 (2000) 979], but also in implicit memory. Control experiments confirmed that TgCRND8 and non-Tg mice had comparable taste sensitivities in response to appetitive as well as aversive tastes. The study suggests that the CTA paradigm can be a sensitive tool to evaluate deficits in implicit associative learning in APP transgenic mouse models of AD.  相似文献   
65.
The presence of p24 core antigen in the serum of individuals with human acquired immunodeficiency syndrome has been used as one of the important prognostic markers of HIV-1 infection and also as an end point in evaluating antiviral drugs and vaccines. Unfortunately the majority of p24 antigen present in serum exists as an antigenantibody complex and is not detected with the commercial kits currently available to measure p24 antigen. In this study, we report a simple procedure utilizing treatment of serum samples with glycine buffer (pH 1.85) to dissociate antigen-antibody complexes prior to assaying for p24 antigen. A 300% increase in the number of p24-reactive samples and a 3- to 12-fold increase in the quantity of antigen detected were observed when samples were pretreated with 1.5M glycine buffer (pH 1.85) for 1 hr. Glycine treatment of samples did not result in nonspecific positive tests and samples previously shown to be reactive remained positive. In reconstruction experiments the release of antigen was found to be inversely proportional to the amount of p24 antibody present in the serum. The percentage of HIV-1-infected patients positive for p24 antigen was clearly a function of CD4 count. Forty-nine percent of patients with more than 500 CD4 cells and 100% of patients with less than 200 CD4 were p24 positive. The improved sensitivity for detection of p24 provided by this procedure enhances our understanding of the pathogenesis of AIDS by showing that the majority of patients with HIV-1 infection is p24 positive and facilitates the analysis of data obtained in clinical trials involving anti-HIV compounds.  相似文献   
66.
67.
The effect of intermittent courses of recombinant interleukin-2 (rIL-2) on HIV-1 load in patients receiving combination antiretroviral therapy remains uncertain. CPCRA 059 was an open-label, randomized, multicenter trial in which 511 patients with HIV-1 infection and CD4+ cell counts of > or = 300/mm3 who were receiving antiretroviral therapy were assigned to receive no rIL-2 (255 patients [controls]) or subcutaneous rIL-2 in dosages of 4.5 MIU (130) or 7.5 MIU (126) twice daily for 5-day courses every 8 weeks to maintain CD4+ cell counts that were twice the baseline value or > or = 1,000/mm3. The primary objective of this study was to compare the effects of the two doses of rIL-2 and no rIL-2 on viral load and CD4+ cell counts over 12 months. There was no difference in the following viral load measurements between the rIL-2 treatment groups and the control treatment group: percentage of patients with viral loads of <50 copies/mL at 12 months (p =.55), time to viral load of > or = 50 copies/mL for patients who had baseline viral loads of <50 copies/mL (p =.35), and change in viral load from baseline for patients who had viral loads of > or = 50 copies/mL at baseline (p =.63). At each follow-up visit, the change in CD4+ cell count from baseline was significantly greater in the rIL-2 treatment groups than in the control treatment group, with a mean difference of 251/mm3 at month 12 (95% confidence interval, 207-295; p <.0001). No unanticipated adverse experiences were seen in this trial, to our knowledge the largest randomized evaluation of rIL-2 treatment conducted to date.  相似文献   
68.
We have modified a standard isolation procedure for C1r and C1s, which employs IgG-Sepharose affinity chromatography followed by DEAE chromatography. As usual, all steps were performed at low temperature and two proteolytic inhibitors, PMSF and NPGB, were added during affinity chromatography on IgG-Sepharose. The novel condition was to keep the pH at pH 6.1 during the entire procedure, where activation was markedly depressed. In addition, purification was improved by washing the IgG-Sepharose column with a buffer free of added divalent cations immediately prior to elution of the C1r and C1s with EDTA. The final yields of highly purified C1r and C1s were about 20%; little or no activated material was detected in these highly purified fractions.  相似文献   
69.
We report the capacity of CD40 ligand (CD40L)-negative T cell clones to activate human B cells. CD40L-negative T cells induce a level of B cell proliferation 10–20% of that seen with normal T cells. The signal provided by the negative clones is synergistic with that derived from a CD40L transfectant, and restores B cell proliferation to normal levels, showing that CD40L-negative T cell clones are not inherently inhibitory for B cells. Although their capacity to induce proliferation was much reduced, CD40L-negative T cell clones were still strong inducers of B cell differentiation to plasma cells. This differentiation to plasma cells was inhibited by a CD40L transfectant. The data are discussed with regard to the normal in vivo mechanism for maintaining B cell memory and memory antibody responses to T-dependent antigens.  相似文献   
70.
Summary The present study was designed to investigate the relationships between premenstrual symptomatology, locus of control, anxiety, and depression in women with normal menstrual cycles. Sixty-nine female participants completed a survey, comprised of the Menstrual Distress Questionnaire (MDQ; Moos, 1968), Levenson's (1981) locus of control scales, the Depression Anxiety Stress Scale (DASS; Lovibond and Lovibond, 1995), and a questionnaire constructed by the researchers based on the DSM-IV criteria for Premenstrual Dysphoric Disorder (PMDD). Both overall and specific subtypes of premenstrual symptomatology were found to correlate with external locus of control, anxiety, and depression. In addition, locus of control was found to moderate the relationship between premenstrual symptomatology, anxiety and depression. Finally, women who were in the premenstrual phase when completing the questionnaire scored significantly lower on the internal scale than those in either the follicular or early luteal phases. It was concluded that an external locus of control may be associated with a susceptibility to depression or anxiety when certain premenstrual or postmenstrual changes are experienced. Received August 10, 2002; accepted January 12, 2003 Published online February 19, 2003 Abbreviations · ANOVA · Analysis of variance · DASS · Depression anxiety stress scale · LOC · Locus of control · MANOVA · Multivariate analysis of variance · MDQ · Menstrual distress questionnaire · PMDD · Premenstrual dysphoric disorder · PMS · Premenstrual syndrome Acknowledgement The authors would like to thank John Reece, Department of Psychology and Disability Studies, RMIT University, Melbourne, Australia, for assistance with data analysis. Correspondence: Dr. Andrew Francis, Department of Psychology and Disability Studies, Faculty of Applied Science, RMIT University, P.O. Box 71, Bundoora, Victoria 3083, Australia; e-mail: andrew.francis@rmit.edu.au  相似文献   
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