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41.
OBJECTIVE: There is substantial evidence demonstrating the aggravating effect of human immunodeficiency virus (HIV) infection on the progression of chronic hepatitis C virus (HCV) infection. There is however, little data on the affect of certain factors which could affect liver pathology findings in patients with concomitant HIV infection such as the duration of HIV infection or T-cell subpopulation counts. We examined pathology findings in patients with concomitant HIV and HCV infections to determine the impact of immunodepression. PATIENTS AND METHODS: We reviewed liver pathology data collected in patients with concomitant HIV and HCV infections grouping patients according to severity of the liver pathology: group 1 = cirrhosis or active hepatitis; group 2 = minimally active hepatitis or histologically normal liver. Transparietal liver biopsies were obtained for the work-up of viral hepatitis or because of long-term unexplained fever or suspected lymphoma. Epidemiological and biological data were obtained from medical files. The duration of the liver disease was estimated from the date of exposure to risk of immunodepression as determined by the peripheral CD4+ and CD8+ counts. All pathology specimens were read by two pathologists who established the Knodell score for each patient. RESULTS: Fifty patients were included: 23 were classed in group 1 and 28 in group 2. The Knodell score was significantly different between the two groups, 11 +/- 4 and 4 +/- 3 respectively (p < 0.0001). Disease duration was similar for the two groups: mean 8 years. Mean CD4+ count was significantly higher in group 1: 312/mm3 versus 110/mm3 for group 2 (p = 0.0057); as was the mean CD8+ count (758/mm3 versus 360/mm3, p = 0.0013). For the entire study population, there was a significantly negative correlation (p < 0.05) between the Knodell score and the CD4+ count (r = 0.31) and for the CD8+ count (r = 0.41). CONCLUSION: HCV-related liver pathology in patients co-infected with HIV depends on the level of immunodepression. CD8+ counts are better correlated with pathology findings than with CD4+ counts.  相似文献   
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During a 9 month period, 50 consecutive children were evaluated by ultrasound to determine the size, location (mesenteric vs para-aortic), number, shape and texture of abdominal lymph nodes in a normal paediatric population. High resolution linear array transducers were used with graded compression. Nodes ranging from 10 to 20 mm were recorded in the majority of subjects. In all cases mesenteric lymph nodes were larger and more numerous than para-aortic nodes. Para-aortic lymph nodes were not seen in isolation.  相似文献   
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Vascular wall fibrinolytic system proteins are believed to play a pivotal role in atherogenesis. Tissue-type plasminogen activator (t-PA) and urokinase plasminogen activator (u-PA) influence persistence of luminal thrombi and proteolysis of extracellular matrix, respectively. The major physiologic inhibitor of t-PA and u-PA is plasminogen activator inhibitor type 1 (PAI-1). All three of these fibrinolytic system proteins have been detected in vascular endothelial cells, smooth muscle cells, and macrophages by light microscopic immunohistochemistry. This study was undertaken to delineate, by immunoelectron microscopy, the loci of PAI-1 in smooth muscle cells from intact morphologically normal and atherosclerotic human arteries as well as in isolated and cultured smooth muscle cells from arteries. In intact vessels, PAI-1 immunoreactivity was associated with contractile filaments in cells in both normal and atherosclerotic tissues. Lipid-laden smooth muscle cells in atherosclerotic vessels were mainly of the synthetic phenotype and displayed lesser amounts of PAI-1 associated with rough endoplasmic reticulum and contractile filaments. Isolated smooth muscle cells exhibited either a contractile or synthetic phenotype. In the cells with a contractile phenotype, PAI-1 was associated with the contractile elements, whereas in the cells with a synthetic phenotype, the PAI-1 was associated predominantly with elements of the endoplasmic reticulum. Because PAI-1 is associated predominantly with contractile filaments in smooth muscle cells, the net amount of immunodetectable PAI-1 appears to be greater in contractile compared with synthetic phenotype cells.  相似文献   
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Cognitive accounts of panic predict that panic disorder patients will be particularly prone to misinterpret autonomic sensations. Several studies have produced results consistent with this prediction, but each is open to alternative interpretation. To clarify matters, 2 studies administered the Body Sensations Interpretation Questionnaire (BSIQ) to panic patients and controls. Panic patients were more likely to interpret ambiguous autonomic sensations as signs of immediately impending physical or mental disaster and were more likely than other anxiety disorder patients and nonpatients to believe these interpretations. In a 3rd study, a brief version of the BSIQ was shown to have satisfactory test-retest reliability, to change with treatment, and to discriminate treatments that varied in their effects on panic.  相似文献   
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Melanoma is prone to spread to the brain and is the third most common source of intracranial metastasis. Patients usually present with signs and symptoms of increased intracranial pressure, a new focal neurologic deficit, or seizures. Contrasted magnetic resonance imaging (MRI) is the single most valuable imaging modality. Surgical therapy is the appropriate choice for single lesions that are accessible, especially if they are causing significant mass effect or are located in the posterior fossa. Patients with several intracranial metastases who undergo resection of all lesions may have a similar prognosis to those with single resected lesion. Stereotactic radiosurgery appears to provide good local control of small lesions. External beam radiotherapy may provide some benefit to patients, and is often used in conjunction with surgery or stereotactic radiosurgery. To date, chemotherapy has been limited because of chemo-resistance and drug delivery issues. Future directions for treatment may include local sustained delivery of either chemotherapy or immunoregulatory molecules.  相似文献   
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28 isolates of canine parvovirus type-2 (CPV-2) were obtained from dogs with hemorrhagic gastroenteritis in Italy. The antigenic structure of CPV-2 isolates was characterized, using four discriminating monoclonal antibodies. In addition, four vaccinal strains were examined. Similar to reports from Australia and the United Kingdom, a much higher prevalence of CPV-2a (25/28 isolates) was observed than the other variant type, CPV-2b (3/28 isolates). DNA fragments (2.2 kbp) of representative strains of CPV-2, CPV-2a and CPV-2b were amplified by the polymerase chain reaction (PCR) and the products were digested by the restriction enzymes (RE) RsaI, HpaII, HindIII and PvuII. The RvaI enzyme allows the differentiation of CPV-2 from CPV-2a and CPV-2b.  相似文献   
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