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991.
A 44-year-old male patient was hospitalised with paranoid schizophrenia in 1985. Depot neuroleptic treatment was started which successfully prevented further psychotic relapses for the next ten years. His myasthenia gravis started with bulbar signs in 1997 and the symptoms soon became generalized. The diagnosis of myasthenia gravis was confirmed by electromyography, by positive anticholinesterase test and by the detection of anti-acetylcholine receptor antibodies in the serum. Mediastinal CT examination showed enlarged hilar lymph nodes on the left but no thymic pathology was observed. Mediastinoscopy was performed and biopsies were obtained from the affected nodes. Histology revealed sarcoidosis. The patient suffered respiratory crisis following the thoracic intervention (in September 1998). Combined oral corticosteroid (64 mg methylprednisolone/e.o.d.) and azathioprine (150 mg/day) treatment regimen was initiated and complete remission took place in both the myasthenic symptoms and the sarcoidosis. The follow-up CT scans showed no mediastinal pathology (January 2000). During steroid treatment a transient psychotic relapse occurred which was successfully managed by supplemental haloperidol medication added to his regular depot neuroleptics. The patient currently takes 150 mg/day azathioprine and receives 40 mg/month flupentixol depot i.m. His physical and mental status are stable and he has been completely symptom free in the last 24 months. The association of myasthenia gravis and sarcoidosis is very rare. To our best knowledge no case has been reported of a patient suffering from myasthenia gravis, sarcoidosis, and schizophrenia at the same time.  相似文献   
992.
The cerebral representation of category information was examined in a single word priming paradigm, during which the N400 component of the event-related potential (ERP) was recorded. The visual half-field paradigm was employed in order to selectively stimulate the two hemispheres. To investigate which aspects of category membership are relevant in producing priming, two types of related stimuli were presented. In one condition pairs of exemplars had a higher amount of feature overlap (e.g., MOSQUITO-FLEA) than in the other (e.g., SOFA–VASE). Significant priming was obtained only for stimuli in the high feature overlap condition and then only when these were presented to the left visual field (LVF)/right hemisphere (RH). This finding was interpreted within our recent model of semantic memory wherein the right hemisphere represents items on the basis of distributed individual features, whereas the left hemisphere (LH) represents semantic information locally, within a spreading activation system, where priming occurs exclusively through associative links. It was concluded that knowledge regarding category membership is maintained in the RH, on the basis of feature coding.  相似文献   
993.
PURPOSE: To retrospectively determine a biometric algorithm for calculating relative lung volume in fetuses with normal lungs and of a wide range of gestational ages by using proved independent variables and to retrospectively investigate the use of this algorithm in fetuses with pulmonary hypoplasia. MATERIALS AND METHODS: Total lung volume (TLV) was measured by using planimetry on single-shot rapid acquisition with relaxation enhancement magnetic resonance (MR) images obtained in 91 fetuses with ultrasonographically (US) normal chests and 28 fetuses with US-determined pulmonary hypoplasia. All fetuses were aged between 18 and 38 weeks gestation. Analysis of covariance was used to identify parameters that were not different between the fetuses with US-determined normal and those with US-determined abnormal chests, and these variables were used to construct an algorithm for calculating predicted lung volume. The relative lung volume-that is, the observed lung volume expressed as a percentage of the predicted lung volume-was then calculated in fetuses with pulmonary hypoplasia. RESULTS: There was no significant difference in mean maternal or gestational age between the two fetus groups. Stepwise regression analysis was used to generate the following equation for predicting fetal lung volume on the basis of independent biometric indexes, with a correlation coefficient of 0.93: TLV = (0.52 . LV) + (0.33 . BD) - (0.06 . FL) - 13.7, with TLV and liver volume (LV) in milliliters and biparietal diameter (BD) and femoral length (FL) in centimeters. In the fetuses with normal chests, relative lung volume varied between 51% and 134%. In the fetuses with pulmonary hypoplasia, relative lung volume varied between 6% and 70%. CONCLUSION: The predicted lung volume in fetuses of a wide range of gestational ages can be calculated with a high degree of accuracy, enabling prenatal MR imaging lung volumetry in which relative lung volume is used to quantify fetal pulmonary hypoplasia.  相似文献   
994.
The present study describes a novel meshing procedure that provided successful low-risk papillomavirus propagation and reproducible wart induction in human foreskin xenografts. The initial HPV6 and/or 11 inocula were collected from clinically excised human wart tissues and confirmed to be free of HPV16, 18 and 31 by PCR analysis. Human foreskin grafts were collected from a circumcision clinic, and pre-inoculated with HPV virions by scarification. Meshing was carried out with a Zimmer Skin Grafter Mesher. Grafts were cut to appropriate size (1cm x 1cm or 5mm x 5mm) for cutaneous or subcutaneous grafting to NIH-nu-bg-xid mice under halothane anesthesia. Cutaneous xenografts were dressed with antibiotics and protective band-aids for 3 weeks. In the paralleled experiment using the same viral stock containing both HPV6 and 11, and matched grafts, no visible papillomas were observed in non-meshed cutaneous xenografts (n = 4 up to 6 months). In comparison, six of eight cutaneous xenografts treated with the meshing procedure formed visible papillomas within 4 months. This high frequency of distinct papilloma induction over the surface of meshed xenografts were reproduced in subsequent experiments with viral stocks containing both HPV11 and 6 (8 out of 10 grafts), or with a single-type HPV11 inoculum (80-100%). In contrast, an initial viral stock of single-type HPV6 provided lower frequency and more delayed papilloma induction. Serial passage of HPV6 in the meshed xenograft appeared to improve both the induction frequency and growth rate up to the 3rd generation. Histology, in situ hybridization, and immunohistochemical analysis revealed similarity of xenograft warts to those observed in the clinic. The highly reproducible papilloma induction rate and successful viral stock propagation associated with the meshing procedure provide a novel feature in the HPV xenograft model.  相似文献   
995.
OBJECTIVE: We recently reported the efficacy of rofecoxib in two randomized controlled trials in chronic low back pain (CLBP). The objectives of this report are to present data regarding the onset of efficacy of rofecoxib from these trials and propose methods for reporting onset. RESEARCH DESIGN AND METHODS: Patients were aged 18-75, with non-radicular CLBP for >or= 3 months. Patients were randomized to rofecoxib 25mg, 50 mg, or placebo once daily for 4 weeks. Assessments included Low Back Pain and Bothersomeness scales every morning and Relief from Starting Pain after the first dose at 0.5, 1, 2, 3, 4 h, bedtime, and next morning. Onset of meaningful relief was measured by Time to Confirmed 50% Reduction in Pain and Time to Confirmed 'Slightly' or 'Not At All' Bothersome Pain. Onset of perceptible pain relief was measured by Time to At Least 'A Little' Confirmed Pain Relief. RESULTS: 690 patients entered. Significantly more patients treated with rofecoxib had compared with 1/3 receiving placebo. Median meaningful relief compared to placebo: 60.4, 58.4, and 34.7% for rofecoxib 25mg, 50 mg, and placebo (p< 0.001). Median time to meaningful relief for rofecoxib was 2 days, 1 day sooner than placebo. Rofecoxib was superior to placebo by bedtime after the first dose. CONCLUSIONS: Approximately 2/3 of patients achieved meaningful pain relief with rofecoxib time to onset of meaningful relief was about 2 days, but superior relief over placebo was seen by bedtime after the first dose. Onset of perceptible pain relief was within 2 h. We propose that measures of onset of analgesic effect include the proportion of patients who achieve meaningful pain relief and in this subgroup, the time-to-onset of confirmed meaningful reduction in pain intensity, time-to-onset of confirmed pain relief, and time to first separation from placebo in the proportion of patients who achieve meaningful pain relief.  相似文献   
996.
Large submacular hemorrhages after verteporfin therapy   总被引:2,自引:0,他引:2  
PURPOSE: To report the occurrence of large submacular hemorrhages after photodynamic therapy with verteporfin in age-related macular degeneration patients with subfoveal choroidal neovascularization (CNV) composed of occult with no classic CNV in whom the hemorrhage precluded determining if additional therapy should be given within 3 months after initiation of treatment. DESIGN: Retrospective, noncomparative case series. METHODS: The records of all age-related macular degeneration patients who received verteporfin therapy for subfoveal lesions composed of occult with no classic CNV between February and July 2001 at The Wilmer Eye Institute were reviewed. Subjects who reported either having undergone a procedure to remove intraocular blood before a month 3 follow-up visit, or who had submacular hemorrhage at the month 3 visit that was severe enough to preclude determining if additional verteporfin therapy should be given were identified. RESULTS: Fifty-five eyes of 52 patients were reviewed. Five eyes (9% [95% confidence interval, 1.4%-16.6%]) developed submacular hemorrhage that precluded determining if additional verteporfin therapy should be given. Visual acuity 3 months after documentation of the hemorrhage decreased a median of 8.5 lines compared with pretreatment acuity. CONCLUSIONS: Even in the absence of acute severe visual acuity decrease, submacular hemorrhage after verteporfin therapy can be associated with severe vision loss and preclude determining if additional therapy should be given.  相似文献   
997.
998.
Rhoptry-associated protein 1 (RAP1) is a merozoite antigen within Plasmodium falciparum rhoptries as yet having no specific function described for it. Synthetic peptides spanning the RAP1 sequence were tested in erythrocyte binding assays to identify possible RAP1 functional regions. Five high activity binding peptides (HABPs) were identified; 26201, 26202, 26203 and 26204 spanned residues 461C-K540 within RAP1 Cys region, whilst 26188 (201T-Y220) was located in p67 amino terminal. The results showed that peptide binding was saturable, some HABPs inhibited in vitro merozoite invasion and specifically bound to a 72 kDa protein in red blood cell membrane. HABP possible function in merozoite invasion of erythrocytes is also discussed.  相似文献   
999.
Several studies indicate that socially advantaged women are more dissatisfied with their bodies than socially disadvantaged women. These findings have been based on women's current social class, and no attention has been paid to the social class of her family of origin or to intergenerational social mobility. In the present research 912 54-year-old women from a prospective birth cohort study provided self-report data on current body esteem (appearance and weight dimensions). Childhood and adult social class (manual versus non-manual) were defined based on father's occupation and own or partner's occupation, respectively. This information and the highest educational qualifications recorded by age 26 were gathered prospectively. Indicators of current and adolescent body mass index (BMI) were computed from height and weight values collected at ages 15 (or 11) and 53-54 years. Multiple regression was used to examine the relationship between midlife body esteem and childhood social class, adult social class, educational qualifications, and social mobility, unadjusted and adjusted for BMI. Women from the non-manual classes as adults were more dissatisfied with their weight than women from the manual classes as adults, for a given BMI. Adjusting for BMI, downwardly mobile women were more satisfied with their appearance than stable non-manual women. Adjusting for BMI, higher educational qualifications were associated with more dissatisfaction with weight and with appearance, and education appears to be more important than occupationally defined social class in explaining body dissatisfaction. A clearer understanding of the relationship between socio-economic position and body dissatisfaction demands that the following distinctions are made: weight versus appearance satisfaction, education versus occupation, and current social class versus intergenerational social mobility.  相似文献   
1000.
BACKGROUND: Ward rounds are an essential responsibility for doctors in hospital settings. Tools for guiding and assessing trainees' performance of ward rounds are needed. A checklist was developed for that purpose for use with trainees in internal medicine. OBJECTIVE: To assess the content and construct validity of the task-specific checklist. METHODS: To determine content validity, a questionnaire was mailed to 295 internists. They were requested to give their opinion on the relevance of each item included on the checklist and to indicate the comprehensiveness of the checklist. To determine construct validity, an observer assessed 4 groups of doctors during performance of a complete ward round (n = 32). The nurse who accompanied the doctor on rounds made a global assessment of the performance. RESULTS: The response rate to the questionnaire was 80.7%. The respondents found that all 10 items on the checklist were relevant to ward round performance and that the item collection was comprehensive. Checklist mean-item scores differed between levels of expertise: junior house officers 1.4 (1.0-1.9); senior house officers 2.0 (1.5-2.9); specialist trainees 2.5 (1.8-2.8), and specialists 2.7 (2.3-3.5); median (range) (P < 0.001). A significant correlation was found between global observer scores and nurse scores (r = 0.56, P < 0.001). CONCLUSION: The checklist, developed for assessing trainees' performance of ward rounds in internal medicine, showed high content validity. Construct validity was supported by the higher scores of experienced doctors compared to those with less experience and the significant correlation between the observer's and nurses' global scores. The developed checklist should be valuable in guiding and assessing trainees on ward round performance.  相似文献   
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