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991.
992.
Left ventricular (LV) deformation with ventricular septal shift is one of the most distinctive echocardiographic observations in patients with chronic right ventricular (RV) pressure overload (PO). However, little is known about the effects of RVPO on LV performance and regional synchrony. Accordingly, our objective was to test the hypothesis that chronic RVPO affects regional wall motion, synchronicity, and global LV function using a novel speckle-tracking approach to quantify and characterize regional LV wall motion dyssynchrony. Displacement and strain imaging echocardiographic studies were performed in 20 patients with RVPO from pulmonary arterial hypertension or pulmonic stenosis (mean age 53 +/- 16 years, New York Heart Association class 2.6 +/- 0.7, and peak RV systolic pressure 73 +/- 28 mm Hg) and 20 age-matched normal subjects (mean age 47 +/- 16 years). Segmental signals from 6 segments around the mid-LV short axis were defined as dyssynchronous if their changes were opposite to that of the global LV signal at each time frame, and overall LV dyssynchrony was calculated as the percentage of dyssynchrony in all 6 segments within the specified time interval from onset of QRS to the end of isovolumic relaxation. RVPO was associated with a large degree of regional dyssynchrony with paradoxical ventricular septal motion observed by displacement imaging (21 +/- 6%, p <0.05 vs control group), which was closely associated with LV eccentricity index (r = 0.79, p <0.05) and LV myocardial performance index with linear regression (r = 0.76, p <0.05). In contrast, strain imaging showed uniform segmental radial thickening in the RVPO group, which was similar to the control group, and suggests that there was no intrinsic LV contractile dyssynchrony. In conclusion, LV wall motion dyssynchrony assessed by displacement imaging, not intrinsic contractile dyssynchrony by strain imaging, coexists with LV chamber deformation with ventricular septal shift and is closely associated with impairment of LV performance.  相似文献   
993.
Plasmapheresis for the treatment of hypertriglyceridemia has previously been performed in patients with sudden onset severe hypertriglyceridemia and acute pancreatitis; however, only a few reports of this procedure have been published. We report here on a case showing severe hypertriglyceridemia during asparaginase (Asp) treatment for acute lymphocytic leukemia (ALL), and give an overview of a lipid‐lowering apheresis therapy. To prevent the complication of pancreatitis due to hypertriglyceridemia, we performed plasma exchange (PE) three times using fresh frozen plasma. PE remarkably reduced both serum triglyceride and total cholesterol levels from 5430 mg/dL to 403 mg/dL and from 623 mg/dL to 204 mg/dL, respectively. The causes of severe hyperlipidemia in this patient were considered to include: the Asp treatment for ALL, and a genetic background with a heterozygote of familial lipoprotein lipase (LPL) defect syndrome, because the patient's plasma LPL level after intravenous heparin injection was low at 137 ng/mL. Hence, PE using fresh frozen plasma may be useful not only to remove lipoproteins, but also to supply defective factors, such as LPL, in similar cases.  相似文献   
994.
Siba, a new platelet-specific alloantigen involved in a case of platelet transfusion refractoriness is reported. The IgG platelet alloantibody was detected in a multiply transfused patient of Japanese extraction (Sib), by the presence of HLA antibodies. After transfusion of HLA-compatible platelets, the patient suffered from refractoriness. Adsorption studies with pooled lymphocytes showed that the serum contained anti-platelet activity. Family studies indicate that Siba is inherited as an autosomal codominant trait and separate from HLA and Baka. As of this report, segregation from Zw(PlA) and Yuk (Pen) antigen systems have not yet been determined. The gene frequency of Siba in the Japanese population is estimated to be 0.136.  相似文献   
995.
Immortalization and malignant transformation are important steps in tumor development. The ability to induce these processes from normal human epithelial cells with genetic alterations frequently found in the corresponding human cancer would significantly enhance our understanding of tumor development. Alterations in several key intracellular regulatory pathways (the pRB, p53, and mitogenic signaling pathways and the telomere maintenance system) appear to be sufficient for the neoplastic transformation of normal human cells. Nevertheless, in vitro transformation models to date depend on viral oncogenes, most prominently the simian virus 40 early region, to induce immortalization and malignant transformation of normal human epithelial cells. Here, we demonstrate a transformation model creating oral-esophageal cancer cells by using a limited set of genetic alterations frequently observed in the corresponding human cancer. In a stepwise model, cyclin D1 overexpression and p53 inactivation led to immortalization of oral keratinocytes. Additional ectopic epithelial growth factor receptor overexpression followed by c-myc overexpression as well as consecutive reactivation of telomerase induced by epithelial growth factor receptor sufficed to transform oral epithelial cells, truly recapitulating the development of the corresponding human disease.  相似文献   
996.
p53 point mutations in primary human gastric carcinomas   总被引:12,自引:0,他引:12  
Summary p53 point mutations in primary gastric carcinomas were analyzed by performing cDNA deoxynucleotide sequencing of the gene. Out of 16,9 (56.3%) primary gastric carcinoma cases, including early cancer, showed one or more p53 point mutations in their open-reading frame, and 4 out of 9 cases had a p53 point mutation within highly conserved domains. The characteristics of the p53 mutation spectrum observed in primary tumors were (a) frequent mutation at an A:T pair (50%, 7 out of 14 mutations), (b) high transversion incidence (29%, 4 out of 14 mutations), (c) no transition at CpG, and (d) no G:C to T:A transversion. Our results suggest that p53 mutation is a common event in gastric carcinoma occurring from the early stage of progression with its specific mutation spectrum.Abbreviation PCR-SSCP polymerase chain reaction single-strand conformation polymorphism  相似文献   
997.
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   
998.
AIM: Nonalcoholic steatohepatitis (NASH) is a severe form of nonalcoholic fatty liver disease (NAFLD), and progresses to the end stage of liver disease. Biochemical markers of liver fibrosis are strongly associated with the degree of histological liver fibrosis in patients with chronic liver disease. However, data are few on the usefulness of markers in NAFLD patients. The aim of this study was to identify better noninvasive predictors of hepatic fibrosis, with special focus on markers of liver fibrosis, type VI collagen 7S domain and hyaluronic acid. METHODS: One hundred and twelve patients with histologically proven NAFLD were studied. RESULTS: The histological stage of NAFLD correlated with several clinical and biochemical variables, the extent of hepatic fibrosis and the markers of liver fibrosis were relatively strong associated. The best cutoff values to detect NASH were assessed by using receiver operating characteristic analysis: type VI collagen 75 domain ≥5.0 ng/mL, hyaluronic acid ≥43 ng/mL. Both markers had a high positive predictive value: type VI collagen 7S domain, 86% and hyaluronic acid, 92%. Diagnostic accuracies of these markers were evaluated to detect severe fibrosis. Both markers showed high negative predictive values: type VI collagen 7S domain (≥5.0 ng/mL), 84% and hyaluronic acid (≥50 ng/mL), 78%, and were significantly and independently associated with the presence of NASH or severe fibrosis by logistic regression analysis. CONCLUSION: Both markers of liver fibrosis are useful in discriminating NASH from fatty liver alone or patients with severe fibrosis from patients with non-severe fibrosis.  相似文献   
999.
Intervertebral disc degeneration and associated spinal disorders including low back pain are a leading source of morbidity and a major cause of work disability as well as increased health care costs. Recent advance of molecular biology enable us to utilize these new techniques for understanding disc cell function and mechanisms of disc degeneration. Furthermore, these new technology may open novel therapeutic strategy such as application of growth factors, stem cell therapy, and gene therapy to regenerate degenerated intervertebral discs.  相似文献   
1000.
A 34-year-old woman visited our hospital complaining of dry cough. Chest radiography and computed tomography showed bilateral multiple infiltrative shadows over the lung field. After an initial diagnosis of pneumonia, antibiotics were administered, but the therapy failed to improve the symptoms and abnormalities observed on the chest radiograph. The patient was then admitted to our hospital. The bronchoalveolar lavage fluid (BALF) was slightly bloody, but we were not able to make any specific findings in BALF. In order to confirm the pathological diagnosis, video-assisted thoracoscopic lung biopsy was performed aiming at the right middle and lower lobes. There were bleeding pulmonary infarctions in a biopsy specimen from the right middle lobe. Atypical cells positive for human chorionic gonadotropin (hCG) proliferated in the pulmonary arteries, and so a diagnosis of pulmonary embolic metastasis of choriocarcinoma was made. After the diagnosis, it became clear that urine and serum hCG values were very high. The patient has since received systemic chemotherapy in the gynecology unit at our hospital. Pulmonary embolic metastasis of choriocarcinoma diagnosed by video-assisted thoracoscopic lung biopsy has never been reported in the literature. However, early hCG measurement may have detected this syndrome in the earlier stages, and pulmonary metastasis of choriocarcinoma should be considered in the differential diagnosis of women with past pregnancy presenting with intractable multiple pulmonary shadows.  相似文献   
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