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951.

Objectives

Our aim was to review the literature on the prevalence and impact of critical-illness related corticosteroid insufficiency (CIRCI) on the outcomes of patients with severe community-acquired pneumonia (CAP).

Methods

We reviewed Cochrane, Medline, and CINAHL databases (through July 2008) to identify studies evaluating the adrenal function in severe CAP. Main data collected were prevalence of CIRCI and its mortality.

Results

We screened 152 articles and identified 7 valid studies. Evaluation of adrenal function varied, and most studies used baseline total cortisol levels. The prevalence of CIRCI in severe CAP ranged from 0% to 48%. Among 533 patients, 56 (10.7%) had cortisol levels of 10 μg/dL or less and 121 patients (21.2%) had cortisol levels of 15 μg/dL or less. In a raw analysis, there was no significant difference in mortality when patients with cortisol levels less than 10 μg/dL (8.6 vs 15.5%; P = .55) or less than 15 μg/dL (12.4 vs 16%; P = .38) were compared with those with cortisol above these levels. In the meta-analysis, relative risk for mortality were 0.81 (confidence interval, 0.39-1.7; P = .59; χ2 = 1.04) for cortisol levels less than 10 μg/dL and relative risk was 0.67 (confidence interval, 0.4-1.14; P = .84; χ2 = 1.4) for cortisol levels less than 15 μg/dL.

Conclusions

A significant proportion of patients with severe CAP fulfilled criteria for CIRCI. However, CIRCI does not seem to affect the outcomes. Noteworthy, the presence of elevated cortisol levels is associated with increased mortality and may be useful as a prognostic marker in patients with severe CAP.  相似文献   
952.
A rare case of cavernous angioma of the dura mater at the convexity is presented. In comparison with the more common cavernous hemangiomas that arise from dural sinuses, the ones on the convexity have a much better prognosis. They do not seem to be associated with spontaneous hemorrhage, their removal is simpler and, transoperatory bleeding, if it occurs, is scanty. Computerized tomography detects the presence of cavernous angiomas of the convexity in only 70% of the cases, magnetic resonance imaging in 100%.  相似文献   
953.
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955.
Burkitt's-like lymphoma of T-cell type   总被引:1,自引:0,他引:1  
Over an 8-yr period, we studied 29 cases of Burkitt's/Burkitt's-like lymphoma and unexpectedly found 2 Burkitt's-like cases of the T-cell type. One case presented as diffuse adenopathy in a 35-yr-old male. A second case presented as a jaw mass in a 2-yr-old girl with Down's syndrome. Histologically, each case demonstrated usual Burkitt's-like morphology (intermediate-size cells with high nuclear/cytoplasmic ratio, 1 to 3 prominent nucleoli, high mitotic rate, basophilic cytoplasm, and cytoplasmic vacuolation). Ultrastructural morphometric data corroborated the Burkitt's-like nature of these neoplasms. Immunologically, the neoplasms were of "novel" T-cell phenotype, as seen in peripheral T-cell lymphoma (PTL). The cases showed variable expression of activation antigens (e.g., Ia) and weak to moderate expression of proliferation antigens as measured by Ki-67. This modest proliferative activity (less than 25% Ki-67 expression) contrasts with Burkitt's-like lymphomas of the B-cell type which usually show greater than 80% Ki-67 expression. The jaw tumor also demonstrated positivity for human progenitor cell antigen (HPCA) as commonly found in leukemia. Both cases mimic granulocytic sarcoma by virtue of their eosinophilic/myelocytic recruitment--a phenomenon previously reported in association with PTL. The patients have survived 62 wk and 20 wk, respectively, surpassing the survival rates seen in our concurrent B-cell Burkitt's-like lymphomas (12 wk). Burkitt's-like lymphoma of the T-cell type appears to be a distinctive immunological subset of potential clinical and prognostic relevance.  相似文献   
956.
Changes in sulcal cerebrospinal fluid (CSF) volume have been related to the neurodegeneration hypothesis in schizophrenia. Fifty-three (24 neuroleptic-naive) schizophrenics and a control group (n=26) were studied with MRI to assess regional sulcal CSF values relative to the total volume of brain lobes (prefrontal, orbital, temporal, parietal, and occipital). Segmentation of brain structures was performed using an automatic Talairach-based method. Relative CSF volumes were adjusted for age by means of linear regression from normal subjects; the corrected values were used to assess their relationship with illness duration and age of onset (AOS). The volume of sulcal CSF on prefrontal and temporal lobes (bilateral) was significantly greater in schizophrenic patients and showed a significant positive correlation with illness duration not found in the other regions studied. No significant association between CSF volumes and AOS was found in any region. Our findings support the existence of a degenerative process in schizophrenia located in prefrontal and temporal areas.  相似文献   
957.
High levels of triglycerides and free fatty acids have been implicated in the pathogenesis of type 2 diabetes mellitus (DM). Congenital generalized lipodystrophy (CGL) is an autosomal recessive syndrome characterized by intense whole body reduction of subcutaneous fat. Its clinical manifestations appear during the first years of life. However, DM is usually a late event. We report a patient with CGL, diagnosed at 4 months of age, who has severe hypertriglyceridemia (serum triglyceride 12.34 mmol/l and cholesterol 3.90 mmol/l), muscular hypertrophy, hepatomegaly and DM (fasting glycemia 25.9 mmol/l). Hepatic biopsy revealed steatosis and fibrosis. A modified normolipidic (composed of medium chain triglycerides) normocaloric normoproteic milky diet and insulin therapy were instituted. After 1 month treatment a reduction of serum glucose and triglyceride levels (4.13 mmol/I and 7.7 mmol/l, respectively) was noted, with later normalization, which led to the discontinuation of insulin therapy. The patient has been maintaining good control with diet alone, presenting normal serum lipid levels (triglycerides 1.07 mmol/l, total cholesterol 2.71 mmol/l) and the following glycemic profile at OGTT: 0' 4.4 mmol/l; 30' 7.0 mmol/l; 60' 3.8 mmol/l; 90' 5.3 mmol/l, and 120' 5.2 mmol/l. The disappearance of hepatic steatosis was evidenced by a biopsy obtained 1 year after the beginning of treatment. In conolusion, this report suggests that the DM occurring in CGL can be precipitated by high triglyceride levels.  相似文献   
958.
Key to understanding somatosensation is the form of how the mechanical stimuli are represented in the evoked neuronal activity of the brain. Here, we focus on studies that address the question of which components of the evoked neuronal activity in the somatosensory system represent the stimulus features. We review experiments that probe whether these neuronal representations are essential to somatosensation. We also discuss recent results that suggest how the somatosensory stimuli are represented in the brain during short-term memory. Finally, we review data that show the neuronal correlates of a decision during somatosensory perception.  相似文献   
959.
To identify the main determinants of health services utilization by children under five years of age, a population-based study using systematic sampling was conducted in Rio Grande, Southern Brazil. Twelve previously trained interviewers applied a standardized home questionnaire to mothers in order to obtain data on living conditions, medical consultations, and hospitalization for children under five years of age. Among 514 children covered by the study, 50% had required consultation with a physician in the previous three months and 11% had been hospitalized in the previous twelve months. Acute respiratory infection was responsible for almost two-thirds of the consultations and half of the hospitalizations. After adjusting the analysis for several confounders, the most important determinants were children's age, father's schooling, and type of home construction. Identification of these factors can contribute to adequate planning of future health interventions and to reach children in the community who need but have not received health care.  相似文献   
960.
A simple index for detection of gestational diabetes mellitus   总被引:2,自引:0,他引:2       下载免费PDF全文
The conventional screening test for gestational diabetes mellitus is measurement of plasma glucose 1 hour after 50 g glucose by mouth. The sensitivity and specificity of this test are lower than desirable; we therefore developed an index including other plasma constituents. In a preliminary study, 138 pregnant women had the standard oral glucose load screening test, and plasma fructosamine and total proteins were measured, in addition to glucose, in the 1-hour samples. An index value (I) was calculated as [fructosamine (micro mol/L) divided by total proteins (g/L)]x[glucose (mmol/L) divided by 100]. Cut-off values for I were then assessed in a second prospective study, of 642 pregnant women. Definitive diagnosis of gestational diabetes was by oral glucose tolerance test (OGTT). The index was also assessed in terms of fetal macrosomia (birthweight>or=4000 g). With a cut-off value of I=27.2, sensitivity was 98%, specificity 89%, diagnostic efficiency 90%, positive likelihood ratio 8.76. Application of the index would have avoided 42% of the OGTTs demanded by the standard screening test, reducing false positives from about 24% to 10%. Predictive efficacy for macrosomia was 10.3% versus 7.9%. Our index offers an efficient screening test for gestational diabetes, and with more stringent cut-off points may be applicable as a single-step diagnostic procedure.  相似文献   
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