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1.
Antiphospholipid antibody syndrome (APLS) is a rare disorder characterized by a hypercoagulable state. Manifestations include arterial or venous thrombosis, recurrent fetal wastage, coronary artery disease, valvular heart disease, dilated cardiomyopathy, pulmonary artery hypertension, and intracardiac thrombus. Most commonly mitral valve is affected followed by aortic and then tricuspid valve. In this report, a rare case of spontaneous aortic thrombosis with tricuspid stenosis uncomplicated by other valve lesions is presented with clinical and echocardiographic studies and computed tomographic images.  相似文献   
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BACKGROUND: Lung infection with Burkholderia cepacia complex before lung transplantation in patients with cystic fibrosis is a major risk factor for decreased post-operative survival rates compared with those of patients colonized with the more common opportunistic pathogen Pseudomonas aeruginosa. Because adherence to mucosal surfaces is an important initial step in infection, we investigated the use of non-toxic neutral polysaccharides and a sugar alcohol to prevent adherence of B cepacia complex to allograft airway epithelium. METHODS: We used human airway explants prepared from donor tracheobronchial tissue to test the effect of dextrans and xylitol in inhibiting the binding of Burkholderia cepacia complex. We used immunofluorescence and electron microscopy to determine the distribution of bacteria in the explants. RESULTS: Burkholderia cepacia complex bound to the explants and was found only in the surface mucus layer. Dextran 40 kd applied before adding the bacteria decreased the number of bound organisms by 80% to 99%. Smaller molecular mass dextrans (4 and 20 kd) were ineffective. Xylitol inhibited bacterial binding by 67% to 85%. Both agents seemed to decrease the thickness of the surface mucus, suggesting that they may indirectly inhibit bacterial binding by removing adherent surface mucus. CONCLUSIONS: Treating donor lungs with dextran 40 kd or xylitol before (and possibly after) surgery may inhibit the adherence of Burkholderia cepacia complex to airways and may prevent or decrease subsequent infection of the allografts.  相似文献   
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Morbidity and mortality in puerperal cerebral venous thrombosis (CVT) can be reduced by arresting the progression of thrombosis using heparin. However, conventional dose of heparin requires monitoring of coagulation parameters and carries a risk of haemorrhage. The present study involved 56 patients of puerperal CVT with CT evidence of haemorrhagic infarction. Twenty nine of these patients received low dose heparin till 30th post-partum day or symptomatic relief. Their clinical features and severity were similar to 27 patients who did not receive heparin. The mortality and morbidity at discharge was significantly less (P < 0.001) in heparin treated group. There were no haemorrhagic complications. Low dose heparin is safe and effective in cerebral venous thrombosis, even with haemorrhagic infarction.  相似文献   
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The diagnosis of thyroid tumors is critical for clinical management; however, tumors with follicular architecture often present problems. We evaluated the diagnostic use of the protein expression of four genes that were found to be upregulated in papillary thyroid carcinoma compared to normal thyroid (LGALS3, FN1, CITED1 and KRT19), and of the mesothelial cell surface protein recognized by monoclonal antibody HBME1 in thyroid tumors. Tissues from 85 carcinomas (67 papillary, six follicular, eight Hürthle cell and four anaplastic) and 21 adenomas were evaluated by immunohistochemistry for the expression of these gene protein products, for example, galectin-3 (GAL3), fibronectin-1 (FN1), CITED1, cytokeratin-19 (CK19) and HBME1. Non-neoplastic thyroids (29 adenomatous and 14 thyrotoxic hyperplasia, and 59 normal) were also studied. The expression of all five proteins was significantly associated with malignancy, and highly specific (> or = 90%) for carcinoma compared to adenoma. GAL3, FN1 and/or HBME1 expression was seen in 100% of carcinomas (85/85) and in 24% of adenomas (5/21). Coexpression of multiple proteins was seen in 95% of carcinomas and only 5% of adenomas (P<0.0001). Coexpression of FN1 and GAL3 (FN1+ GAL3+, 70/85) or FN1 and HBME1 (FN1+ HBME1+, 53/85) was restricted to carcinomas, while their concurrent absence (FN1- GAL3- or FN1- HBME1-, 18/21 adenoma) was highly specific (96%) for benign lesions. Among non-neoplastic thyroids, adenomatous hyperplasia frequently expressed GAL3 (n=16), CK19 (n=9) and CITED1 (n=7), but the expression was predominantly focal in contrast to the diffuse expression in carcinomas. An immunohistochemical panel consisting of GAL3, FN1 and HBME1 may be useful in the diagnosis of follicular cell-derived thyroid tumors.  相似文献   
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The effects of forced swimming stress (15 minutes per day) on body weight, food intake, blood sugar, water intake, and urine output were studied in adult male Wistar rats on the first, seventh, fourteenth and 21st days in different subgroups. There was a significant initial decrease in the body weight up to 14 days followed by a regain in the body weight, which was sustained until 21 days. Though there was no change in the food intake initially for 7 days, after 14 days a significant increase in the food intake was observed. A significant hypoglycemia was observed throughout the entire period of stress. More significant fall in the blood sugar level was observed in the initial period of exposure of stress (1-7 days). There was a significant reduction in the water intake in the stressed animals. Urine output decreased significantly up to 7 days of stress, though it got marginally increased later. Thus, repeated stress may produce a reduction in body weight only initially, which is accompanied with an initial decrease in food and water intake also. The peak response to stress was seen after 7 days of stress exposure. There was a gradual recovery back to normal in the body weight, food intake, and water intake and urine output when stress period was prolonged to 14-21 days. This is suggestive of the adaptation of the organism to repeated exposure of similar kind of stress.  相似文献   
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PURPOSE: To develop a genome-based classification scheme for clear-cell sarcoma (CCS), also known as melanoma of soft parts (MSP), which would have implications for diagnosis and treatment. This tumor displays characteristic features of soft tissue sarcoma (STS), including deep soft tissue primary location and a characteristic translocation, t(12;22)(q13;q12), involving EWS and ATF1 genes. CCS/MSP also has typical melanoma features, including immunoreactivity for S100 and HMB45, pigmentation, MITF-M expression, and a propensity for regional lymph node metastases. MATERIALS AND METHODS: RNA samples from 21 cell lines and 60 pathologically confirmed cases of STS, melanoma, and CCS/MSP were examined using the U95A GeneChip (Affymetrix, Santa Clara, CA). Hierarchical cluster analysis, principal component analysis, and support vector machine (SVM) analysis exploited genomic correlations within the data to classify CCS/MSP. RESULTS: Unsupervised analyses demonstrated a clear distinction between STS and melanoma and, furthermore, showed that CCS/MSP cluster with the melanomas as a distinct group. A supervised SVM learning approach further validated this finding and provided a user-independent approach to diagnosis. Genes of interest that discriminate CCS/MSP included those encoding melanocyte differentiation antigens, MITF, SOX10, ERBB3, and FGFR1. CONCLUSION: Gene expression profiles support the classification of CCS/MSP as a distinct genomic subtype of melanoma. Analysis of these gene profiles using the SVM may be an important diagnostic tool. Genomic analysis identified potential targets for the development of therapeutic strategies in the treatment of this disease.  相似文献   
10.
Intermittent dysfunction of mechanical mitral valve prosthesis is an uncommon condition. It carries serious clinical implications if unrecognized. Here, we present a case of a 28‐year‐old female with a history of rheumatic multivalvular disease, for which she had undergone double valve replacement and tricuspid annuloplasty. Six months later, she presented with heart failure. Clinical examination revealed intermittent loss of closing clicks followed by a pansystolic murmur at the apex, suggestive of mitral prosthetic valve dysfunction. We highlight the echocardiographic findings of paroxysmal mitral valvular regurgitation secondary to prosthetic valve malfunction secondary to prosthetic valve thrombosis.  相似文献   
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