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The authors sought to determine whether the performance of the dexamethasone suppression test (DST) could be enhanced by expressing cortisol as a function of dexamethasone. Because cortisol concentration is a function of the reciprocal of dexamethasone concentration, this relationship was approximated by calculating the product of cortisol and dexamethasone as a dexamethasone suppression index. Preliminary assessment of test performance measures (sensitivity, specificity, and predictive power) showed that use of the dexamethasone suppression index was an improvement over the use of cortisol levels alone. Factoring dexamethasone levels into post-dexamethasone cortisol level measures may enhance the utility of neuroendocrine assessment in psychiatry.  相似文献   
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An antibody reacting with Schwann sheaths of myelinated somatic and unmyelinated autonomic peripheral nerve was found in sixty-one out of seventy-one chronic, and nine out of ten acute, Chagas' disease sera. Indirect immunofluorescence (IFL) was carried out on rat, mouse and human somatic nerves and rat sympathetic nerves with initial serum dilutions of 1 : 10, and the staining reached a final titre of 1 : 320 in some cases. The antibodies fixed complement and were absorbed out by lyophilized epimastigotes of T. cruzi. Lipid extraction of the tissue sections enhanced the staining of myelinated nerve, whereas unfixed unmyelinated sympathetic nerve was strongly reactive. Central nervous tissue did not display any positive staining on neurons, glial cells or periaxonal sheaths. Furthermore, by using a double-labelled IFL technique, it was possible to show that a rabbit antiserum raised against guinea-pig spinal cord and the chagasic anti-nerve antibodies reacted with different structures in the rat sciatic nerve. These findings suggest that the reactive antigen(s) could be located on Schwann cells. The majority, but not all, of the chagasic individuals with anti-nerve antibodies also showed the sarcolemmal and endothelial staining (EVI) previously described in Chagas' disease. The possible recognition of Schwann cell antigens by circulating antibodies in Chagas' disease could be relevant, since an autonomic denervation has been postulated as a pathogenic mechanism of cardiomyopathy and megaviscera in this condition.  相似文献   
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One hundred fifty-six of 1,250 sera from patients with presumed connective tissue and related diseases showed vascular staining on mouse liver cryostat sections when they were routinely checked for antinuclear factor by the indirect immunofluorescence test. In a third of the cases, the vascular immunofluorescent pattern was given by the EVI antibody reacting with the plasma membrane of striated muscle fibers and endothelial cells, as has been recently described to occur in Chagas' disease. This led to the detection of previously unsuspected Trypanosoma cruzi infection in 67.8% of the serum samples in which the EVI antibody was detected after observation of a positive vascular pattern with mouse liver cryostat sections. On the other hand, no significant relationship between Chagas infection and sera with other anti-striated-muscle immunofluorescent patterns that also showed a vascular staining on mouse liver cryostat sections was established. Consideration of the vascular pattern observed with the EVI antibody on mouse liver cryostat sections can be helpful in detection of previously ignored T. cruzi infection in patients who have connective-tissue diseases and related conditions. This is of interest in view of the fact that anergic immunodepressive therapy, often used in these patients, significantly alters the host-parasite relationship and may lead to severe dissemination of the parasite.  相似文献   
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The COVID-19 pandemic has significantly impacted daily activities worldwide. University students may have experienced substantial changes in daily living as a result of restrictions on university attendance. The return to normalcy may take a long time, and understanding the influence that shifts in daily routines have had on the lifestyles of university students may inform approaches to support overall well-being. We analyzed changes in the lifestyles of students enrolled at a health sciences university during the COVID-19 pandemic. This longitudinal study took place at the Faculty of Medicine and Nursing in the University of the Basque Country in Spain, and the final sample consisted of 113 nursing students, 109 medical students, and 45 physiotherapy students. Our results demonstrate changes in lifestyles of university students during the pandemic. MedDiet adherence scores and the percentage of students with high adherence increased during the pandemic. This increase was due to the increased consumption of vegetables and nuts. In terms of physical activity, the practice of moderate and intense physical activity was maintained. These results provide important information for both public health authorities and educational institutions to guide strategies to maintain the well-being of students and enhance opportunities for young adults to lead a healthy lifestyle.  相似文献   
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A review of inpatient satisfaction data for MUSC provides both comfort and cause for additional study. Although overall satisfaction rates of 89 and 88 during the period of organizational change indicate stable patient perceptions, one must reflect upon these scores in greater detail. For example, although survey response rates in the 36 percent to 28 percent range appear customary for this type of survey, absolute numbers of discharge responses averaged 496 for the four quarters reported. Some confidence can be taken in the fact that overall survey scores were highly consistent in the 89 to 88 range for the entire reporting period. Moreover, the fact that workforce performance variables such as medication errors and patient occurrence reports did not change indicates that patient care did not deteriorate during this period. Although one could argue that in a time of workforce reduction, employees may work more diligently in order to ensure job security, and that work deterioration may be more apparent over a longer period of observation, this limited view suggests that, at least in the acute phase, work performance was maintained. Future studies should review the relative effectiveness of the specific strategies adopted by MUSC management to ensure high levels of patient care. For example, although MUSC adopted a fairly comprehensive communications effort, it is difficult to discern whether timeliness, variety, or repetition contributed more to the effectiveness of the communications program. Such information could help managers develop focused change implementation strategies. It appears from the inpatient survey data collected by UHC and from the two work performance monitors that MUSC's approach to change management has been able to preserve acceptable levels of patient satisfaction in the face of significant organizational change. Furthermore, these strategies may have been helpful in countering the turbulence caused by large scale change or, at the very least, insulating the care site from potentially negative effects.  相似文献   
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With the increasing use of obstetric echography fetal hydronephrosis has been reported more frequently. The purpose of this study was to identify prognostic factors associated with adverse outcome, such as renal failure and death, in fetal hydronephrosis. One hundred and forty-eight children with fetal hydronephrosis were admitted, submitted to a systematic protocol, and prospectively followed. Prognostic factors associated with fetal echography and clinical and laboratory findings on admission were studied. The median follow-up was 39 months. The analysis was conducted in two steps. In a univariate analysis, variables associated with adverse outcome were identified by the Kaplan-Meier method. The variables that were significantly associated with adverse outcome were then included in a multivariate analysis. This analysis, using the multivariate Cox’s model, was performed to identify variables that were independently associated with a worse prognosis. Only variables that remained independently associated with adverse outcome were included in the final model. After final adjustment by Cox’s multivariate model, three variables were identified as independent predictors of adverse outcome: oligohydramnios, prematurity, and glomerular filtration rate lower than 20 ml/min. Thus, in the presence of oligohydramnios, prematurity, and abnormal renal function, the medical team must plan appropriate follow-up for infants at health centers prepared to investigate and treat uropathies in newborns. Received: 24 August 1998 / Revised: 7 December 1998 / Accepted: 11 December 1998  相似文献   
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OBJECTIVE: To evaluate the appropriateness of the use of total hip joint replacements. DESIGN: Observational study of consecutive patients with a diagnosis of hip osteoarthritis and who had undergone total hip arthroplasty over a 1-year period from seven hospitals. MAIN MEASURES: The appropriateness of the use of hip replacement was judged by explicit criteria developed by a panel of experts using RAND methodology. The length of hospital stay during the admission and complications were recorded 6 months post-operatively. Patients were also surveyed 6 months after discharge to determine whether they believed they had recovered or their satisfaction with the intervention. Appropriateness results of this study were compared with a previous study performed with the same criteria 4 years previously. RESULTS: In total, 784 patients participated in the study. Indications for surgery were considered necessary in 52.2% of cases, appropriate in 21.3%, uncertain in 21.4%, and inappropriate in 5.1%. Differences were found in the rates of appropriateness exclusively from one hospital. At 6 months after discharge, differences between centres were found for the proportion of patients that reported they had recovered from surgery (range 57.7-24.8%) and in the length of hospital stay during admission (range 10-16 days). Improvement in the appropriateness rates were found for all participant hospitals during both periods. CONCLUSIONS: We identified a low percentage of inappropriate indications and differences in some outcomes between centres. Compared with previously, there has been improvement in the use of this technique, although both periods are not methodologically comparable.  相似文献   
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