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腹部外科常见感染性疾病的病原菌及药敏试验研究   总被引:1,自引:0,他引:1  
为了了解本地区本医院腹部外科感染性疾病病原菌的构成比和药物敏感率的变化,指导临床用药,我们采用美国BD公司生产的6B和7D两种增菌瓶采集标本和培养细菌,并用该公司生产的生化板和药敏板,对1994~1996年269例常见的普外科感染性疾病患者的手术标本进行前瞻性的细菌培养和药敏试验研究.  相似文献   
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T-cell survival     
Summary: Like other cells, T cells are dependent on signals from their environment for their survival. Resting T cells are supported in vitro by cytokines such as interleukin (IL)-4, IL-6 and IL-7. The latter two cytokines are made constitutively in animals and hence might affect the lifetimes of their resting T cells. Resting T cells are also kept alive by interaction with an as yet unidentified molecule on the surface of other cells. Activated T cells are also supported in vitro by members of two families of these proteins, the IL-2 family and the interferon-αβ family. Members of the latter family may have effects on activated cells in vivo. Thus although both resting and activated T cells require signals to keep themselves alive, the signals are different for the two types of cells. This perhaps allows the immune response to control the numbers of activated cells during infections without compromising its pool of precursor, resting T cells.  相似文献   
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Selenium status of malnourished hospitalized patients   总被引:1,自引:0,他引:1  
We evaluated selenium (Se) status of 44 hospitalized patients with protein-energy malnutrition. The patients were assigned to "normal" or "low" Se groups-1 and 2, respectively-based on whether the plasma Se level exceeded or was below the value of the mean-2SD of healthy Georgians'. Plasma and erythrocyte Se levels correlated significantly (r = .52, P less than .01). Erythrocyte glutathione peroxidase activity was highly correlated with plasma Se (r = .68) in group 2; there was no significant correlation between these parameters in group 1. In group 2 the mean plasma prealbumin level was significantly lower, and the mean corpuscular volume and serum glutamic oxaloacetic transaminase level were significantly higher compared to group 1. Other nutritional parameters did not correlate with Se status. Concomitant deficiencies of other nutrients were common in both patient groups. Se levels may relate to protein status, and abnormal hematologic and hepatic parameters may reflect low Se status and/or protein-energy malnutrition. Low Se status is common in malnourished patients from a low Se area, and Se supplementation should be included in their nutritional-repletion regimens.  相似文献   
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Tracheobronchopathia osteochondroplastica (TO) is a rare benign disease characterized by the presence of osseous and cartilaginous submucosal nodules projecting into the tracheobronchial tree. Most cases are asymptomatic and discovered incidentally at post‐mortem. We identified a case of TO on thoracic spiral CT and confirmed the diagnosis on bronchoscopy. This article reviews the imaging characteristics of TO, and shows the 3‐D virtual bronchoscopic and multiplanar reconstruction appearances of TO.  相似文献   
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The present study compared the accuracy of ventilation perfusion scintigraphy (VQS) and CT pulmonary angiography (CTPA) for the diagnosis of pulmonary embolism. This was a prospective observational study of 112 patients with suspected pulmonary embolism (PE) who could be studied with both investigations within 24 h. Results were compared to final diagnosis at completion of 6-month follow up, using receiver operating characteristic (ROC) analysis. Pulmonary embolism was diagnosed in 27 referred patients (24%). The sensitivity and specificity of VQS and CTPA were similar to that reported from the literature. A normal VQ scan had the highest negative predictive value (100%), while a high-probability VQ scan had the highest positive predictive value (92%). There was no overall difference (area under the ROC curve (AUC)) between VQS (AUC (95% CI) = 0.82 (0.75,0.89)) and CTPA (AUC = 0.88 (0.81,0.94)) for the diagnosis of PE. Among patients with abnormal chest X-rays, CTPA (AUC 0.90 (0.83,0.97)) appeared somewhat better than VQS (AUC 0.78 (0.68,0.88)) but this difference did not reach statistical significance. In this instance, CTPA is at least as accurate as VQS and may provide an opportunity to make alternative diagnoses.  相似文献   
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