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71.
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   
72.
The FAO/WHO/UNU recommendations for energy requirements assume that the energy cost of sleep is equal to the basal metabolic rate (BMR). We have tested the validity of this assumption by analysing overnight and BMR measurements made by whole-body indirect calorimetry. Data from 80 healthy subjects measured on a total of 246 occasions have been used. In a subgroup of 40 normal lean subjects the mean ratio of overnight metabolic rate (Overnight MR): BMR was 0.95 (range 0.85 - 1.02, s.d. 0.04). The mean ratio of lowest sleeping metabolic rate (Lowest SMR): BMR was 0.88 (range 0.83 - 0.96, s.d. 0.04). Ratios of Overnight MR: BMR were not significantly affected by different levels of exercise on the preceding day. This ratio was significantly higher for subjects who were obese, late pregnant or attached to ECG electrodes. With the exception of the late pregnant subjects these groups had the same Lowest SMR:BMR ratios as the normal lean subjects, indicating that the higher Overnight MR was caused by disturbed sleep. The data suggest that the use of BMR to estimate overnight energy expenditure would introduce an average overestimate of approximately 5 per cent during the actual hours of sleep, but that when applied over 24 h the error becomes negligible.  相似文献   
73.
David Goldberg  M Tan  M Dale Sarradet  Marsha Gordon 《Dermatologic surgery》2003,29(2):161-3; discussion 163-4
BACKGROUND: A nonablative 350-microsec, 585-nm, flashlamp pulsed dye laser is currently being used for the treatment of rhytides. OBJECTIVE: To analyze both clinical rhytid improvement and electron microscopic evidence of ultrastructural changes after treatment with a nonablative 350-microsec, 585-nm, flashlamp pulsed dye laser. RESULTS: At 6 months after two treatments, 40% of the treated subjects noted mild improvement in rhytid appearance. Nontreating physician evaluation revealed some degree of improvement in 50% of the treated subjects. Mild improvement in quality and texture of the skin was also reported by 50% of the subjects. Electron microscopic evaluation showed ultrastructural changes that are consistent with new collagen formation. CONCLUSION: Treatment with a nonablative 350-microsec, 585-nm, flashlamp pulsed dye laser can lead to both clinical and electron microscopic evidence of improvement in photo-damaged skin.  相似文献   
74.
Antagonist activity of bulbocapnine on DA1 versus DA2 dopamine receptors was studied simultaneously in a dog under pentobarbitone anaesthesia and without phenoxybenzamine pretreatment. Fenoldopam (SK&F 82526) injected into the renal artery was the DA1 agonist and dipropyl dopamine or piribedil injected into the femoral artery were the DA2 agonists. Both at 0.5 and 1 mg kg-1 doses intravenous bulbocapnine caused nearly equal inhibition of DA1 and DA2 dopamine receptor-mediated responses. Our results show that under these experimental conditions bulbocapnine is not a selective DA1 dopamine antagonist.  相似文献   
75.
This study compares the characteristics of general practitioners and a pen and paper test in the detection of psychiatric disorder in primary care settings. A psychiatrist interviewed a stratified sample of 283 patients drawn from 590 consecutive new illnesses seen in 15 general practices. Research diagnoses could be made in between one-quarter and one-third of the consecutive new illnesses. Two different research diagnostic systems agreed quite well with one another about who should be regarded as a psychiatric 'case' - although agreement between them for individual diagnoses was less impressive. Research diagnoses of psychiatric illnesses could be made in approximately 30% of new episodes of illnesses seen. If the DSM-3 system was used as a criterion of 'caseness', the specificity of the general health questionnaire was 75.4%, and the sensitivity was 87.1%. The general practitioners had fewer false positives than the questionnaire, but they were much more likely to miss psychiatric cases. Use of the general health questionnaire could increase their sensitivity from about 50% to 95%.  相似文献   
76.
Preoperative biochemical liver function tests and computerized axial tomographic (CAT) scans were performed on 100 patients as part of a prospective randomized study of treatments for liver metastases from colorectal cancer. The CAT scans reliably reflected the presence of disease in most patients but only accurately demonstrated the number and location of metastases in 43% of the patients. Extrahepatic metastases were present in 35 patients but were only seen on the CAT scans in three of these patients. The biochemical tests, which were useful for detecting hepatic metastases, were alkaline phosphatase (AP), lactic dehydrogenase (LDH), and carcinoembryonic antigen (CEA). When hepatic disease was minimal, these tests were less likely to be elevated than when there was extensive disease. Even with the combination of late generation CAT scans and biochemical tests, the accurate quantification and location of hepatic metastases and extrahepatic disease require a surgical assessment.  相似文献   
77.
Torques generated in one subject during the early postoperative period were measured with a telemeterized total hip component. The patient was examined during gait, stair ascent, rising from a chair, and single-limb stance. The torques were plotted against both the resultant joint contact force and the force component directed along the stem axis. During gait, the maximum torque was 35 Nm, recorded at a walking velocity of 1.7 m/sec. The peak torques during stair ascent and during rising from a seated position were found to be 23 and 15 Nm, respectively. The maximum value for torque measured in this study was 37 Nm during one attempt at single-limb stance. Comparison of plots for torque versus stem-axis component for the four activities shows that the torque increased more rapidly for chair exits than for gait up to resultant contact force values of as much as 1,000 N. For stair ascent, the same was true to values of 1,400 N. Within any given activity, the relationship between stem torque and resultant or stem-axis force showed considerable variability. These results indicate that experiments evaluating the stability of femoral components in total hip arthroplasty should incorporate a component directed along the stem axis, as well as a component normal to the plane of the prosthesis. The results also suggest that theoretical stress analysis models should consider the broad variability in the orientation of the joint force at the hip.  相似文献   
78.
A pilot study was conducted of the biological characteristics of the leukemia cells of newly diagnosed patients with poor prognosis acute myelogenous leukemia (AML). This study included measurements of the pretherapy proliferative rate of the leukemia cells in vivo, assessment of differentiation in vivo during remission induction therapy, and the level of expression of the fms, myc, and IL1β genes in pretherapy leukemia cells. Short cell cycle times were characteristic of the best prognostic category and were associated with a rapid reduction in marrow leukemia cells in cytosine arabinoside (araC)-sensitive patients. Expression of c-fms was associated with rapid reduction in marrow leukemia cells during araC therapy and with a successful treatment outcome. Expression of the IL1β gene was associated with short remissions. These studies suggest that when compared to newly diagnosed standard prognosis AML, the leukemia of poor prognosis patients is more likely to exhibit long cell cycle times, low levels of fms expression, and is less likely to be associated with myeloid differentiation during remission induction therapy. © 1993 Wiley-Liss, Inc.  相似文献   
79.
Though individual tests thought to assess frontal lobe function have been administered to patients with schizophrenia for many years, approaches in which a number of tests thought to tap a single function or brain region have rarely been used. Such an approach might define a critical test or a common dysfunctional cognitive process. In the present study four putative neuropsychological tests of frontal lobe integrity, namely, the Wisconsin Card Sorting Test, the Category Test, Trail Making B, and verbal fluency, were administered to 28 patients with schizophrenia. Seventy-five percent performed abnormally on at least one test. However, relationships among the test results were difficult to characterize, either by correlation or factor analysis. A hierarchical arrangement in which "higher order" tests proscribe performance on "lower order" tests did not appear to be present. Regarding sensitivity, Trails B, the only timed test, was most frequently impaired and verbal fluency was least frequently impaired. The results suggest that the tests assess somewhat different aspects of frontal lobe function, and that no single frontal lobe test is uniquely sensitive to cognitive impairment in schizophrenia.  相似文献   
80.
Summary The incidence of strains producing transferable -lactamases capable of hydrolyzing third generation cephalosporins or aminothiazole-oximino substituted monobactams in five Buenos Aires hospitals during a four month period was studied. These enzymes were categorized by 1) MIC 1 mg/l for third generation cephalosporins; 2) MIC < 0.06 mg/l for third generation cephalosporins combined with clavulanic acid or sulbactam; 3) sensitivity to imipenem or cephamycins (excluding permeability mutants); and 4) transferable resistance by conjugation. -lactamases hydrolyzing aminothiazole-oximino substituted monobactams were produced by 17.2% of Enterobacteriaceae from intensive care unit patients; 3.6% from inpatients of other units and 1.2% from outpatients. Producers were mainlyKlebsiella spp. (45/46) resistant to aminoglycosides (most of them AAC 3 — AAC 6 producers). Three strains had a an isoelectric point of 6.0, two of 6.5 and three of 7.7. TEM-1 -lactamase (isoelectric point 5.4) was detected in 6/8 strains. An inocolum effect was observed in 40/46 strains. AKlebsiella pneumoniae strain preserved since 1982 also produced a transferable -lactamase hydrolyzing aminothiazole-oximino substituted monobactams.
Vorkommen von Bakterienstämmen mit erweitertem Breitspektrum -Laktamasen in Argentinien
Zusammenfassung Während einer Zeit von vier Monaten wurde an fünf Krankenhäusern in Buenos Aires nach dem Vorkommen von Stämmen mit Bildung übertragbarer -Laktamasen gesucht, die Cephalosporine der dritten Generation oder aminothiazol-oximino-substituierte Monobaktame hydrolysieren. Kriterien für die Selektion dieser Enzyme waren 1) MHK-Werte von 1 mg/l für Cephalosporine der dritten Generation; 2) MHK-Werte von < 0,06 mg/l für Drittgenerationscephalosporine in Kombination mit Clavulansäure oder Sulbactam; 3) Empfindlichkeit gegenüber Imipenem oder Cephamycinen; 4) Resistenz übertragbar. Zur Bildung von -Laktamasen mit hydrolytischer Aktivität gegen Aminothiazol-oximinosubstituierte Monobaktame waren 17,2% der Enterobacteriaceae-Isolate von Intensivpflegepatienten befähigt, 3,6% der Isolate von Patienten von anderen Stationen und 1,2% der Isolate von ambulanten Patienten. Die meisten der Stämme, die diese Enzyme bildeten (45/46), waren aminoglykosidresistenteKlebsiella spp. (Synthese von AAC 3-AAC 6). Der isoelektrische Punkt lag bei drei Enzymen bei 6,0, in zwei Fällen bei 6,5 und in drei Fällen bei 7,7. Sechs von acht Stämmen bildeten TEM-1 -Laktamase. Bei 40 der 46 Stämme wurde ein Inokulumeffekt festgestellt. Die Bildung übertragbarer -Laktamasen mit hydrolytischer Wirkung gegen Aminothiazolyl-oximino-substitutierte Monobaktame wurde in einem bereits seit 1982 gelagertenKlebsiella pneumoniae-Stamm nachgewiesen.
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