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11.
OBJECTIVES: This study developed a new acquired immunodeficiency syndrome (AIDS) severity system by including diagnostic, physiological, functional, and sociodemographic factors predictive of survival. METHODS: Three-hundred five persons with AIDS in Boston were interviewed; their medical records were reviewed and vital status ascertained. RESULTS: Overall median (+/- SD) survival for the cohort from the first interview until death was 560 +/- 14.4 days. The best model for predicting survival, the Boston AIDS Survival Score, included the Justice score (stage 2 relative hazard [RH] = 1.25, 95% confidence interval [CI] = 0.80, 1.96; stage 3 RH = 1.76, 95% CI = 1.15, 2.70), a newly developed opportunistic disease score (Boston Opportunistic Disease Survival Score; stage 2 RH = 1.35, 95% CI = 0.90, 2.02; stage 3 RH = 2.10, 95% CI = 1.38, 3.18), and measures of activities of daily living (any intermediate limitations, RH = 1.84, 95% CI = 1.05, 3.21; any basic limitations, RH = 2.60, 95% CI = 1.44, 4.69). This model had substantially greater predictive power (R2 = .17, C statistic = .68) than the Justice score alone (R2 = .09, C statistic = .61). CONCLUSIONS: Incorporating data on clinically important events and functional status into a physiologically based system can improve the prediction of survival with AIDS.  相似文献   
12.
The development of selective irreversible ligands has proven to be an invaluable technique for the isolation, purification and characterization of many receptor proteins. An isothiocyanato-derivative of the muscarinic antagonist aprophen was synthesized and evaluated as a potential irreversible ligand for muscarinic receptors. This compound (aprophit) displaced [3H]N-methylscopolamine binding from rat cerebral cortex with a Ki of 3.1 x 10(-7) M. The inhibition was concentration-dependent and could not be reversed by extensive washing. Aprophit inhibited the acetylcholine-stimulated release of catecholamines from isolated, perfused guinea pig adrenal glands in a concentration-dependent manner. This inhibition was not reversed by perfusing the tissue with Locke's solution and was not due to a non-selective acylation by the isothiocyanate function. The data suggest that aprophit is selectively acylating muscarinic receptor proteins and thus may be useful in their further characterization.  相似文献   
13.
The (R)-( + )- and (S)-( – )-enantiomers of the anticholinergic compound, oxyphencyclimine, were synthesized from (R)-( – )- and (S)-( + )-2-cyclohexyl-2-hydroxy-2-phenylethanoic acid, respectively. The potencies of the enantiomers were compared using a cholinergic receptor binding assay. The (R)-( + )-enantiomer inhibited binding 29 times more potently than the (S)-( – )-enantiomer.  相似文献   
14.
Previous investigators have reported a high prevalence of depressive symptoms in drug-dependent patients. Given the responsiveness of depressive disorders to both psychological and pharmacological treatments, it is desirable to find an economical, efficient screening instrument to detect depressive disorders in this population. In this study, 6 depression symptom screening scales (Beck Depression Inventory, Hamilton Depression Scale, Raskin Depression Scale, Degree of Illness Rating, Symptom Checklist 90 Overall, and Depression Subscale) based on either clinician interview or patient self report, were compared according to their utility in detecting cases of depression among 64 applicants for treatment at a substance abuse treatment unit of a community mental health center. The criteria for a case of depression were the Research Diagnostic Criteria (RDC) which are specified and operationalized. Cases identified using previously described cutoff scores on the screening scales were compared to rates based on the RDC and sensitivity and specificity were determined. The results showed that: (1) although the sensitivity of the symptom scales was applicable, ranging from 65--94%, the specificity was less impressive, ranging from 39--61%, and (2) the Beck Depression Inventory, a 13-item patient self report was the most sensitive and specific and is recommended for screening drug-dependent populations for depression.  相似文献   
15.
Velo-cardio-facial syndrome (VCFS) and DiGeorge syndrome (DGS) are developmental disorders characterized by a spectrum of phenotypes including velopharyngeal insufficiency, conotruncal heart defects and facial dysmorphology among others. Eighty to eighty-five percent of VCFS/DGS patients are hemizygous for a portion of chromosome 22. It is likely that the genes encoded by this region play a role in the etiology of the phenotypes associated with the disorders. Using a cDNA selection protocol, we isolated a novel clathrin heavy chain cDNA (CLTD) from the VCFS/DGS minimally deleted interval. The cDNA encodes a protein of 1638 amino acids. CLTD shares significant homology, but is not identical to the ubiquitously expressed clathrin heavy chain gene. The CLTD gene also shows a unique pattern of expression, having its maximal level of expression in skeletal muscle. Velopharyngeal insufficiency and muscle weakness are common features of VCFS patients. Based on the location and expression pattern of CLTD, we suggest hemizygosity at this locus may play a role in the etiology of one of the VCFS-associated phenotypes.   相似文献   
16.
17.
Psychoactive drug use among practicing physicians and medical students   总被引:5,自引:0,他引:5  
We surveyed random samples of 500 practicing physicians and 504 medical students in a New England state during 1984-1985; 70 percent of the physicians and 79 percent of the students responded. Fifty-nine percent of the physicians and 78 percent of the students reported that they had used psychoactive drugs at some time in their lives. In both groups, recreational use most often involved marijuana and cocaine, and self-treatment most often involved tranquilizers and opiates. In the previous year, 25 percent of the physicians had treated themselves with a psychoactive drug, and 10 percent had used one recreationally. Although most of the use was experimental or infrequent, 10 percent of the physicians reported current regular drug use (once a month or more often) and 3 percent had histories of drug dependence. More physicians and medical students had used psychoactive drugs at some time than had comparable samples of pharmacists and pharmacy students. The results suggest a need for renewed professional education about the risks of drug misuse.  相似文献   
18.
PURPOSE: To assess the educational impact of Accreditation Council for Graduate Medical Education resident work-hour limits implemented in July 2003. METHOD: All trainees in all 76 accredited programs at two large teaching hospitals were surveyed between May and June 2003 (before work-hour reductions) and then between May and June 2004 (after work-hour reductions) about hours, education, and fatigue. Based on changes in weekly duty hours, 13 programs experiencing substantial reduction in hours were classified into a reduced-hours group. Differences in assessments of educational endpoints before and after policy implementation by trainees in the reduced-hours group were compared with those in other programs to control for potential temporal trends, using two-way ANOVA with interaction. RESULTS: The number of respondents was 1,770 (60% response rate). The reduced-hours group reported a significant decrease in time spent directly caring for patients (from 48.5 to 42.3 mean h/wk, P = 0.03), but the volume of important clinical experiences, including procedures, was preserved, as was the sense of clinical preparedness. On 22 questions related to educational quality and adequacy, only three differences in differences were significant, with the reduced-hours group reporting a relative increase in opportunities for research, decrease in quality of faculty teaching, and decrease in educational satisfaction. The percentage of trainees reporting frequent negative effects of fatigue dropped more in the reduced-hours programs than in the other programs (P < 0.05). CONCLUSION: This study shows that it may be possible to reduce residents' hours--and the perceived adverse impact of fatigue--while generally preserving the self-assessed quality, quantity, and outcomes of graduate medical education.  相似文献   
19.
PURPOSE: The increase in managed care has led to questions about the inadequacy of instruction undergraduate medical students receive in curricular areas related to managed care. This study examined (1) the percentages of graduating medical students who felt they had received inadequate instruction in six curricular content areas (CCAs): primary care, care of ambulatory patients, health promotion and disease prevention, medical care cost control, teamwork with other health professionals, and cost-effective medical practice; and (2) whether the market competitiveness of these students' medical schools affected their reports of inadequacy of instruction in these CCAs. METHOD: Data from the Association of American Medical Colleges' Graduation Questionnaires (GQs) from 1994 to 1997 were analyzed. The GQ asked graduating students to rate the adequacy of instruction they had received in the six CCAs. Students' ratings were collapsed into the dichotomous variables "inadequate" and "not inadequate." The market competitiveness of medical schools was determined using the four-stage Market Evolution Model developed by the University HealthSystem Consortium. Only responses from students graduating from medical schools that could be staged for all four years of the study were analyzed. Statistical analyses were performed to determine trends for each CCA by year, across the entire study period, by market stage, and by market stage across the entire study period. RESULTS: A total of 39,136 respondents from 86 medical schools were used in the study. The percentages of graduating medical students who reported inadequate instruction decreased over the study period for five of the six CCAs: primary care (27.6% in 1994 to 13.7% in 1997), ambulatory care (37.4% to 23. 9%), medical care cost control (62.9% to 52.9%) cost-effectiveness of medical practice (62.7% to 53.9%), and health promotion and disease prevention (44.4% to 23.7%); all at p <0.001. The responses for inadequacy of instruction for teamwork with other health professionals remained steady from 1994 to 1996 (10.2% to 10.6%), then increased 21.8% in 1997. Over the course of the study, students graduating from schools in more competitive markets (Stage 3 or Stage 4) were more likely to report inadequate instruction in three CCAs, primary care, ambulatory care, and health promotion and disease prevention, than were those graduating from schools in less competitive markets (Stage 1 and Stage 2). Conversely, students graduating from schools in the more competitive health care markets were less likely to report inadequate instruction in cost-effectiveness and cost control than were students from schools in less competitive markets. CONCLUSION: Graduating students' reports of inadequacy of instruction decreased over the study period for five of the six CCAs, increasing only for teamwork with other professionals. Findings were mixed with regard to the relationship of medical schools' market competitiveness and graduating students' reports of inadequacy of instruction. More research is needed to confirm graduating students' perceptions of the inadequacy of their instruction in CCAs related to managed care, particularly once they have gained experience treating patients in managed care environments.  相似文献   
20.
The phosphorylcholine idiotype (Id)/anti-Id system has been used to study the role of antigen-specific cells in antigen-induced microenvironmental changes. Anti-Id staining of lymph nodes following PC immunization shows the presence of Id on follicular dendritic cells at 12 h and in plasma cells beginning at day 3. Germinal centers began to form at day 3, peaking in size and number at days 8-10. Scattered Id-positive small lymphocytes are present in germinal centers but with rare exceptions over 98% of germinal center cells are Id-negative. Idiotype-positive small lymphocytes are depleted from primary follicles adjacent to germinal centers but not from distant, unstimulated nodes. These results extend previous studies showing architectural alterations in lymph nodes following antigenic stimulation and demonstrate antigen-specific cells are a prominent component of these antigen-induced microenvironmental changes.  相似文献   
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