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151.
We examined differences in the degree of differentiation in intramucosal and submucosal areas of involvement in early colorectal adenocarcinomas of 131 patients and compared these findings with tumor morphology. In addition, K-ras and p53 protein expression was determined in cases where poorly differentiated adenocarcinoma was detected in the submucosa. We identified 6 patients with both intramucosal differentiated (well-to-moderately differentiated) adenocarcinoma and submucosal poorly differentiated adenocarcinoma (MwSp). The morphological tumor type was superficial in all MwSp cases. The observed MwSp adenocarcinomas had a significantly higher frequency of lymphatic invasion than the more common superficial type of adenocarcinoma. Genetic analysis of these MwSp lesions was carried out using the polymerase chain reaction-restriction fragment-length polymorphism (PCR-RFLP) method to detect the presence of K-ras codon 12 point mutations, and an immunologic staining technique was used to identify the presence of p53 protein overexpression. The K-ras mutation rate was 33.3%, and the p53 overexpression rate was 66.7% for the MwSp adenocarcinomas. Our findings suggest that the rapidly reduced histologic differentiation observed in some of these superficial colorectal adenocarcinomas may play a role in their higher degree of invasiveness. Received: November 17, 1999 / Accepted: July 7, 2000  相似文献   
152.
Incidence of human parvovirus B19 DNA detection in blood donors   总被引:2,自引:0,他引:2  
Summary. 1000 serum samples from blood donors were tested for human parvovirus B19 (B19) DNA by a nested PCR assay: six samples were positive for B19 DNA. The frequency was 1/167 (0-6%), considerably higher than previous surveys (0-004-0-03%). Five of the six samples were also positive for anti-B19 IgM, indicating an acute phase of infection. It is recommended to screen for B19 DNA in blood products to prevent transfusion mediated viral infection for those susceptible such as immunocompromised patients and pregnant women.  相似文献   
153.
Cine-magnetic resonance imaging (cine-MRI) creates moving pictures by a video system and turbo-flash method that allow for high-speed MRI. This report describes our experience using this new technique for dynamic imaging using the fast spoiled GRASS (SPGR) sequence to study swallowing in patients with dysphagia following radical surgery for oral cancer. We defined two new parameters, laryngeal elevation and the angle of the epiglottis, to quantify swallowing ability by cine-MRI. These variables were markedly different in patients with dysphagia than they were in healthy controls. Cine-MRI not only provides dynamic images of swallowing but can generate objective measures of swallowing ability as well.  相似文献   
154.
A 57-year-old man consulted our hospital with a history of the gradual onset of dyspnea and a productive cough. Chest computed tomographic (CT) scans showed a nodular shadow in a cavity lesion, and reticulonodular, cystic, and ground-grass opacities in the bilateral lung fields with honeycombing. He was diagnosed as having pulmonary aspergilloma and idiopathic pulmonary fibrosis (IPF). As an outpatient, he suffered from dyspnea upon physical exertion with exacerbation of the high-resolution CT (HRCT) opacities. An inhalation provocation test for Aspergillosis fumigatus was positive and chronic hypersensitivity pneumonitis (CHP) caused by Aspergillus was finally diagnosed. Insidious CHP is sometimes misdiagnosed as IPF. The diagnosis of insidious CHP should be made on the basis of a detailed history, specific HRCT findings, and lymphocyte-dominant bronchoalveolar lavage fluid cell findings.  相似文献   
155.
Objective : A hallmark of the systemic response to an inflammatory stimulus is the release of polymorphonuclear leukocytes (PMNs) from the bone marrow. This study was designed to measure the release of PMNs from the bone marrow and to determine their sequestration in the lung after an intravenous injection of either endotoxin (n = 5) or saline (n = 5). Methods and Results : The thymidine analogue 5′-bromo-2-deoxyuridine (BrdU) was used to pulse label dividing PMNs in the bone marrow of rabbits (n = 13), and immunohistochemistry and morphometry were used to detect the release of BrdU-labeled PMNs into the circulation and to determine their sequestration in the lung. Endotoxin treatment caused a drop in the circulating PMN counts (3.3 ± 0.08 at baseline to 0.12 ± 0.02 × 109/L at 1 hour after endotoxin), which was followed by a neutrophilia at 8 hours (6.3 ± 1.1 × 109/L, p < 0.01), an increase in circulating band cells (0.12 ± 0.01 at baseline to 2.18 ± 0.4 × 19/L at 8 hours, p < 0.001), and an increase in the percentage of BrdU-labeled PMNs (0.01% ± 0.004% at baseline to 26.1% ± 3.2% at 8 hours, p < 0.001). Endotoxemia caused an arteriovenous difference in BrdU-labeled PMNs across the lung (35.9% ± 2.9% versus 26.1% ± 3.1%, mixed venous versus arterial, p < 0.02). Morphometric studies showed that endotoxin caused sequestration of PMNs in the lung (2.2 ± 0.4 versus 1.0 ± 0.2 × 1010, endotoxin versus saline, p < 0.03) with preferential retention of BrdU-labeled PMNs (0.79 ± 0.21 versus 0.039 ± 0.016 × 1010, endotoxin versus saline, p < 0.05). The percentage of BrdU-labeled PMNs in the alveolocapillary walls was higher than in circulating blood (64.01% ± 4.3% versus 26.1% ± 3.2%, p < 0.01) in the endotoxin group. In vitro filtration of cells through 5-mm pore size filters showed that circulating BrdU-labeled PMNs, 8 hours after endotoxin, were preferentially retained in the filters (p < 0.01). Conclusions : We conclude that endotoxemia stimulates the bone marrow to release mature and immature PMNs. Compared to PMNs released from the bone marrow during normal turnover, these PMNs are less deformable and preferentially sequester in the lung microvessels.  相似文献   
156.
We describe the case of a 41-year-old woman with systemic lupus erythematosus (SLE) who suffered from repeated reversible lupus enteritis characterized by marked edematous thickening of the small intestine. Ultrasonography (US) and computed tomography (CT) manifested as an accordion-like appearance and a target-like appearance, respectively. Resolution of gastrointestinal tract wall thickening was observed on follow-up US performed a week after the increase in predinosolone (PSL). We conclude that careful evaluation of sonographic and radiographic findings helps to establish the diagnosis of lupus enteritis.Abbreviations CT Computed tomography - FANA Fluorescent antinuclear antibody - GI Gastrointestinal - SLE Systemic lupus erythematosus - US Ultrasound  相似文献   
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159.
Background and objective:   While recent studies have shown that patients with COPD and patients with asthma exhibit evidence of airway and systemic inflammation, markers of systemic inflammation have not been compared between the two diseases.
Methods:   To evaluate circulating inflammatory markers, blood was sampled from 111 patients with COPD, 75 control subjects and 46 asthmatic patients (some of whom were smokers). Measurements of WCC, serum levels of fibrinogen, high-sensitivity (hs)-CRP, IL-8, IL-6, tumour necrosis factor-α (TNF-α), transforming growth factor (TGF)-β1, tissue inhibitors of metalloproteinase (TIMP)-1, neutrophil elastase and alpha1-antitrypsin (α1-AT) were performed.
Results:   Serum TNF-α, IL-6 and TIMP-1 concentrations were significantly higher in patients with stable COPD and patients with asthma than in control patients. Serum α1-AT levels were significantly higher in COPD patients than in asthmatic patients and control subjects, and serum TGF-β1 levels were higher in asthma patients than in COPD patients. Smoking status had no effect on markers in COPD and asthmatic patients.
Conclusions:   Although COPD and asthma share common markers of systemic inflammation, serum levels of TGF-β1 and α1-AT may reflect differences between the diseases.  相似文献   
160.
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