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Elevated cerebrospinal fluid (CSF) angiotensin I-converting enzyme (ACE) levels have been evidenced in patients with schizophrenia who have been treated with antipsychotics. In order to explore a possible mononuclear cell origin of CSF ACE, the authors determined CSF ACE and CSF mononuclear cell counts from 25 acutely psychotic patients, who had been drug-free for at least 4 months but started on conventional antipsychotic medication within a few days before sampling. No correlations were found between CSF to serum ACE ratio and CSF mononuclear cell counts. However, CSF total mononuclear cell count, CSF lymphocyte count, and CSF mononuclear phagocyte count evidenced significant positive correlations with current dose of antipsychotic medication expressed as chlorpromazine equivalents. The authors conclude that no indication of a relationship between mononuclear cells and CSF ACE activity was found. Surprisingly, a relationship between chlorpromazine dose and CSF mononuclear cell counts was found, which may indicate drug-related changes in cell-mediated immunity. This finding needs replication and further corroboration in well-designed studies.  相似文献   
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OBJECTIVE: To document the quantity and architecture of sleep using objective electrophysiologic assessment in sedated mechanically ventilated pediatric intensive care unit patients over a 24-hr period and to investigate the effect of noise and staff interventions on sleep pattern in these subjects. DESIGN: Prospective observational study. SETTING: Pediatric intensive care unit at a university hospital. PATIENTS: A total of 11 patients studied between September 2000 and June 2001, with ages ranging from 3 to 21 months. All patients were intubated, mechanically ventilated, and sedated with morphine and midazolam infusions. INTERVENTIONS: Limited sleep polysomnograph, staff interventions, and noise levels were continuously monitored during a 24-hr period. MEASUREMENTS AND MAIN RESULTS: Noise levels were consistently >48 dB(A); the highest night peak reached 103 dB(A). Staff interventions lasted for a mean of 240 (SD 90) mins in a 24-hr period. There was no significant difference in the number of interventions between day and night. Severe alterations to sleep architecture were found throughout the 24 hrs, with no diurnal variations. Active sleep was severely reduced to a mean of 3% (SD 4%; range, 0-11%) of total sleep time. There was severe sleep fragmentation as reflected by the high number (mean, 40 [SD 20]) of wake episodes. CONCLUSION: The above findings suggest a significant electrophysiologic abnormality of sleep in the pediatric intensive care unit patients. Our pediatric intensive care unit environment is characterized by both, high noise levels and frequent staff interventions. This study has several limitations and future studies are needed, with larger sample size and an attempt to manipulate the environmental factors to minimize their negative effects on sleep.  相似文献   
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Serum prolactin (PRL) was correlated with clinical symptomatology in 17 drug-free patients suffering from non-affective psychoses. A clear-cut negative correlation was found between the Comprehensive Psychiatric Rating Scale (CPRS) items assessing hallucinations and serum PRL levels (r=-6.14, P=0.009). No correlation was observed between clinical measures (total CPRS score, schizophrenia subscale score or depression and anxiety subscale score) and serum PRL.  相似文献   
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The presence of antiphospholipid antibodies is associated with a clinical syndrome characterised by thrombocytopenia, arterial and venous thromboses and recurrent fetal loss. Among theses antibodies currently detectable in laboratory are the lupus anticoagulant and anticardiolipin antibody. The antigens for theses antibodies are phospholipid-binding-proteins (prothrombin and beta 2 glycoprotein I). The exact mechanism of action of antiphospholipid antibodies remains controversal. The pathogenis of pregnancy loss seems related to the increased incidence of placental infraction. In spite of the improvement in our knowledge on the pathogenic mechanisms of the antiphospholipid syndrome, the standard therapy is still based on anti-platelet or anticoagulant drugs, both for vascular and obstetrical problems. Larger prospective clinical studies are needed to validate therapeutic implications.  相似文献   
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The clinical importance of dysplasia epiphysealis capitis femoris (Meyer dysplasia) is that it is easily mistaken for Legg-Calve-Perthes disease, leading to unnecessary diagnostic procedures and treatments. After a review of 578 children (619 hips) with Legg-Calve-Perthes disease, 17 children (27 hips) in whom both the clinical and radiologic pattern was obviously different could be found and a diagnosis of dysplasia epiphysealis capitis femoris was finally made. The mean age was 2.5 (range 1.9-3.6) years. There were 16 boys and 1 girl. Ten children had bilateral involvement (59%). The capital femoral epiphysis was delayed or was smaller in 26 hips, separated or cracked in 15, and cystic in 6. A normal bone structure was established in approximately 2 to 4 years. The final results assessed by the Mose and the Stulberg classification were good in all 27 hips. This study suggests guidelines for evaluating this rare condition based on the authors' findings and a review of the literature.  相似文献   
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BACKGROUND: Tumor-induced neovessel formation identified by gadolinium-enhanced magnetic resonance imaging (MRI) is a commonly used marker for breast malignancy. The purpose of this study was to assess possible differences in whole-breast vascularity as measured by contrast-enhanced MRI in the ipsilateral and contralateral breasts of patients with unilateral breast malignancies. METHODS: Gadolinium-enhanced MRI of the breast using a Siemens 1.0-T scanner with dedicated breast coil was performed on 22 consecutive patients with histologically confirmed unilateral breast carcinoma. Whole-breast vascularity of the breast containing the carcinoma was estimated as increased, decreased, or similar compared with the contralateral unaffected breast. Breast vascularity was then correlated to clinical factors including tumor size, histology, multifocality, nodal involvement, and patient age and menopausal status. RESULTS: Twenty patients had infiltrating carcinomas, and 2 patients had ductal carcinoma in situ. Four were multifocal. Fifteen of 22 patients demonstrated clear evidence of increased whole-breast vascularity in the ipsilateral breast containing the primary breast cancer compared with the contralateral breast. Although there was no clear correlation between the presence of increased whole-breast vascularity in the cancer-bearing breast with tumor size, histology, grade, mammographic appearance, or patient age and menopausal status, increased vascularity was present in 3 of 4 patients with multifocal disease and in 4 of 5 patients with metastatic disease in the axillary nodes. CONCLUSIONS: Measurable increases in whole-breast vascularity can be identified by contrast-enhanced MRI and appear with increased frequency in the cancer-bearing breast. These findings suggest that factors other than tumor size and histology may influence development of macroscopic vessels during tumor progression and may be indicative of angiogenic tumor biology.  相似文献   
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