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991.
BACKGROUND: We conducted a prospective study to evaluate methods of detecting clients with sexually transmitted diseases (STDs) who were acutely coinfected with human immunodeficiency virus (HIV) in Lilongwe, Malawi. METHODS: After informed consent was obtained, all clients with acute STDs were offered voluntary HIV counseling and testing by 2 rapid antibody tests. Samples from rapid test-negative or -discordant subjects were pooled (50 : 5 : 1) and tested for HIV RNA. Western blots were performed on all rapid test-discordant specimens with detectable HIV RNA. A subset of specimens received p24 antigen testing with standard and/or ultrasensitive methods. Patients with possible acute HIV infection were followed to confirm seroconversion. RESULTS: A total of 1450 clients (34% female and 66% male) agreed to testing, of whom 588 (40.55%) had established HIV infection and 21 (1.45%) had acute infection. Discordant rapid antibody tests identified 7 of 21 (33.3% sensitivity), standard p24 antigen identified 12 of 16 (75% sensitivity), and ultrasensitive p24 antigen identified 15 of 17 (88% sensitivity) acute cases. By definition, the sensitivity of the RNA assay was 100%. CONCLUSIONS: Real-time pooled RNA testing for the detection of acute HIV infection is feasible in resource-limited settings. However, parallel rapid testing and p24 antigen testing are technologically simpler and together may detect approximately 90% of acute cases.  相似文献   
992.
Doppler estimation of pulmonary artery systolic pressure (PASP) from tricuspid regurgitation velocity is a simple approach to the detection of pulmonary hypertension but may be influenced by right ventricular stroke volume. We sought the clinical utility of incorporating Doppler calculation of pulmonary vascular resistance (PVR) into determination of pulmonary hypertension in 578 consecutive patients with tricuspid regurgitation. Right atrial pressure was estimated from vena caval dimensions and collapsibility. Pulmonary hypertension was classified on the basis of a) PASP >35 mmHg, b) age-/gender normalized PASP, c) PVR >2 Wood units. The mean PASP was 40 +/- 13 mmHg and PVR was 1.9 +/- 0.8 Wood units. Standard PASP identified pulmonary hypertension in 58%, compared with 36% by age-/gender normalized PASP (P < 0.0001), and 31% by PVR (P < 0.0001). Of patients who had pulmonary hypertension by PASP, 33% were reclassified as normal on the basis of PVR and 6% were reclassified from normal to pulmonary hypertension. PVR is easy to incorporate into a standard echo exam, and identifies a small group with normal PASP as having PAH, and a larger group of apparently increased PASP as normal.  相似文献   
993.
Background Internal Medicine residency training in ambulatory care has been judged inadequate, yet how trainees value continuity clinic and which aspects of clinic affect attitudes are unknown. Objectives To determine the value that Internal Medicine residents place on continuity clinic and how clinic precepting, operations, and patient panels affect its valuation. Design and measurements A survey on ambulatory care was developed, including questions on career choice and the value of clinical training experiences. Independent variables were Likert-scale ratings (1 = disagree strongly/no value; 3 = neutral; 5 = agree strongly/high value) on preceptors, patients, operations, and resident characteristics. Odds ratios and stepwise multivariate logistic regression with clustering were used to evaluate associations between clinic valuation and independent variables. Subjects Internal medicine residents at 3 residency programs. Results 218 of 260 residents (83.8%) completed the survey. Resident ratings were highest on diversity of illness seen (4.1), medical record systems used (4.1), and contact with preceptors who were receptive to questions (4.8). Resident ratings were lowest on economic diversity of patients (2.7), interruptions from inpatient wards (3.1), and contact with preceptors who taught history and physical exam skills (3.5). High ratings on all precepting issues and nearly all operational issues were associated with valuing clinic. With multivariate analysis, high ratings of preceptors as role models were most strongly associated with valuing clinic (corrected relative risk 3.44). A planned career in general Internal Medicine was not associated with valuing clinic. Conclusions Satisfaction with preceptors, particularly as role models, and clinic operations correlate with the value residents place on continuity clinic.  相似文献   
994.
BACKGROUND: Patients with transient loss of consciousness (TLOC) have poor health-related quality of life (HR-QoL). OBJECTIVE: To test the reliability, validity, and responsiveness of the disease-specific Syncope Functional Status HR-QoL Questionnaire (SFSQ), which yields two summary scales--impairment score (IS) and fear-worry score (FWS). DESIGN: Cohort-study. PARTICIPANTS: 503 adult patients presenting with TLOC. MEASUREMENTS: HR-QoL was assessed using the SFSQ and the Short Form-36 (SF-36) after presentation and 1 year later. To test reliability, score distributions, internal consistency, and test-retest reliability were assessed. To assess validity, scores on the SFSQ and the SF-36 were compared. Clinical validity was tested using known-group comparison. Responsiveness was assessed by comparing changes in SFSQ scores with changes in health status and clinical condition. RESULTS: Response rate was 82% at baseline and 72% at 1-year follow-up. For all scales the full range of scores was seen. Score distributions were asymmetrical. Internal consistency was high (alpha = 0.88 for IS, 0.92 for FWS). Test-retest reliability was moderate to good for individual items and high for summary scales (inter-class correlation = 0.78 for both IS and FWS). Correlations between SFSQ scores and the SF-36 were modest. The SFSQ did not discriminate between patients differing in age and gender but did discriminate between patients differing in number of episodes and comorbid conditions. Changes in SFSQ scores were related to changes in health status and the presence of recurrences but did not vary by TLOC diagnosis. CONCLUSION: The SFSQ is an adequately reliable, valid, and responsive measure to assess HR-QoL in patients with TLOC.  相似文献   
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The Haplotype Genetic Map (HapMap) is an invaluable resource to the cardiovascular researcher, enabling a decrease in cost and an increase in the efficiency and speed of discoveries in the laboratory. As cardiologists, we need to understand the vocabulary of genomics because the translation of scientific findings using HapMap could provide insight for improved care and therapeutic guidance of our patients. Genomics is the evaluation of genes as a dynamic system, in which genes interact to influence biologic pathways, networks and physiology. The HapMap promises to increase the efficiency of genomics in identifying cardiovascular-disease-related genes that could become vital for choosing relevant tests and providing preventative and curative therapies. In this Review, the HapMap will be described, to provide insight into the relevance of this work to cardiovascular practice, to clinical research in cardiovascular disease and to future discoveries in diagnostic and therapeutic modalities.  相似文献   
999.
AIMS: The objective of this study was to describe the proportion and characteristics of patients with type 1 and type 2 diabetes diagnosed with diabetic peripheral neuropathy (DPN) in France, Italy, Spain, and the United Kingdom (UK). METHODS: A cross-sectional survey was administered to general practitioners and diabetes specialists. Existing physicians' records were used to quantify the frequency of DPN diagnoses, and notes from patients' medical charts were used to characterize symptoms. RESULTS: The average number of physicians per country was 41 (range of 34-49). The proportion of diabetes patients diagnosed with DPN ranged from 9.6% (95% CI, 7.1-12.2) in Spain to 23.1% (95% CI, 15.4-30.7) in Italy. Of 913 DPN study patients, 55.0% were male, and 78.5% had type 2 diabetes. Mean age was 64.5+/-12.5 years. A DPN diagnosis was based primarily on symptoms. Approximately 27% of patients had no documented neurological examination. "Prickling" was the most common DPN symptom recorded in France, Italy, and Spain, and "numbness" was the most common in the UK. CONCLUSIONS: Country-specific estimates of DPN diagnosis may reflect clinical management of diabetes and DPN. A substantial number of diagnoses were not associated with a record of a neurological examination.  相似文献   
1000.
Dorsal CA3, but not dorsal CA1, lesioned rats are impaired in the acquisition of a delay nonmatch to place task. In this study, dorsal CA3 efferent fibers in the fimbria were transected; while taking care to spare afferent fibers from the medial septum. Neurophysiological, anatomical tracing, and histochemical data suggest that the transection was selective to dorsal CA3 efferent fibers and spared afferents from the medial septum. Rats showed a deficit for acquisition, but not for performance once learned. One possible explanation is that a small change to the cholinergic inputs to dCA3 caused by a decrease in dorsal CA3 efferent signals reaching the medial septum may impair new learning but not performance of a task once learned.  相似文献   
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