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Cell lines derived from tumors contain numerous chromosomal aberrations and are the focus of study in tumor evolution. The ovarian teratocarcinoma cell line PA-1 demonstrates a single chromosomal aberration: a reciprocal t(15;20)(p11.2;q11.2). A complete molecular genetic analysis was undertaken to characterize this cell line. The PA-1 cell line was studied with fluorescence in situ hybridization (FISH), spectral karyotyping (SKY), bacterial artificial chromosome (BAC) microarray, and Western blotting. Amplification of 20q is frequently implicated in both breast and ovarian cancer; this region contains a number of oncogenes including MDM2, ZNF217, and the ovarian tumor marker WFDC2 (alias HE4). FISH revealed gene amplification of AIB1 (now known as NCOA3) but not STK15 (now known as AURKA). Immunoblot analysis demonstrated 3.6-fold overexpression of the AIB1 protein product, but no elevation of the STK15. BAC cancer gene microarray analysis showed gene amplification of > or =1.20 for five oncogenes. The presence of a consistent single change in PA-1, the t(15;20)(p11.2;q11.2), suggests that the aberration is significant with respect to the transformation status of the cell line. This translocation appears to cause overexpression of AIB1 (and perhaps other proteins), which may provide an immortalizing effect on this cell line.  相似文献   
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Immunohistochemistry profiles of medulloepithelioma (from two 2 1-year-old girls who had 2 cerebral medulloepitheliomas and a 35-week postconceptional female infant with congenital posterior fossa tumor) and neural tube are compared. Microscopically, the tumors contained a medulloepitheliomatous component, manifested as tubular epithelial structures lined by pseudostratified columnar epithelium delineated by well-defined basement membranes. In all cases, glial and neuronal differentiation were noted to differing extents. The medulloepitheliomatous components did not exhibit glial fibrillary acidic protein, neuron-specific enolase, or S-100 protein reactivity. Neurofilament, cytokeratin, and epithelial membrane antigen were focally present in one case. Extensive nestin immunopositivity was confined to the basal cell layer of the epithelium, leaving the luminal surface unreactive or slightly reactive. These cells also displayed a reactivity to vimentin and to microtubuleassociated protein type 5 similar to that of cells of the primitive neural tube. The similarity between the immunohistochemical profile of medulloepithelioma and that of neural tube epithelium suggests a possible reexpression of that component of the genome responsible for neural tube growth and differentiation in medulloepithelioma.  相似文献   
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Clinical Rheumatology - The clinical benefits of rituximab in systemic sclerosis (SSc) are still contentious. The present meta-analysis aimed to systematically assess rituximab’s safety and...  相似文献   
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OBJECTIVES: We sought to highlight the clinical, morphologic, and pathogenetic features in patients with a cleft mitral valve (MV). BACKGROUND: Few studies have addressed the morphologic features of cleft MV and the outcome of these patients. The pathogenetic features, including the developmental relation to an atrioventricular (AV) septal defect, remain unclear. METHODS: We reviewed the patients with cleft MV that were diagnosed by echocardiography since 1980. Patients with an AV canal, ventriculo-arterial discordance, and hypoplastic ventricles were excluded. RESULTS: Twenty-two patients were identified at a median age of 0.5 years (range 0 to 10.6). In three patients, no chordal attachments of the cleft to the ventricular septum were seen. Ten patients had significant mitral regurgitation (MR), and three had subaortic obstruction by the cleft. Associated cardiac lesions and extracardiac features were present in 13 and 10 patients, respectively. During the median follow-up period of 1.5 years (range 0 to 11.8), two patients died of extracardiac causes, and one neonate died of severe subaortic obstruction. Surgical repair was performed in 10 patients at a median age of 5.2 years (range 1.3 to 10.6). Multivariate analysis showed no predictors for MV surgery. One patient was re-operated for mitral stenosis associated with aortic valve stenosis. Follow-up echocardiography demonstrated moderate MR in two unoperated patients and moderate MV stenosis in two operated patients. CONCLUSIONS: A cleft of the MV comprises a wide spectrum. Important morphologic differences exist with an AV septal defect, although the two lesions may be pathogenetically related. Surgical repair always seems possible. Long-term echocardiographic follow-up is warranted.  相似文献   
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We conducted a retrospective study of deep surgical site infections (SSIs) among consecutive patients who underwent lung transplantation (LTx) at a single center from 2006 through 2010. Thirty‐one patients (5%) developed SSIs at median 25 days after LTx. Empyema was most common (42%), followed by surgical wound infections (29%), mediastinitis (16%), sternal osteomyelitis (6%), and pericarditis (6%). Pathogens included Gram‐positive bacteria (41%), Gram‐negative bacteria (41%), fungi (10%) and Mycobacterium abscessus, Mycoplasma hominis and Lactobacillus sp. (one each). Twenty‐three percent of SSIs were due to pathogens colonizing recipients' native lungs at time of LTx, suggesting surgical seeding as a source. Patient‐related independent risk factors for SSIs were diabetes and prior cardiothoracic surgery; procedure‐related independent risk factors were LTx from a female donor, prolonged ischemic time and number of perioperative red blood cell transfusions. Mediastinitis and sternal infections were not observed among patients undergoing minimally invasive LTx. SSIs were associated with 35% mortality at 1 year post‐LTx. Lengths of stay and mortality in‐hospital and at 6 months and 1 year were significantly greater for patients with SSIs other than empyema. In conclusion, deep SSIs were uncommon, but important complications in LTx recipients because of their diverse microbiology and association with increased mortality.  相似文献   
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Severe aortic stenosis is a widespread valve disease, constituting a contraindication to organ transplantation due to cardiovascular morbidity and projected mortality. Mortality after conventional surgical aortic valve replacement in cirrhotic patients depends upon the Child–Pugh class. In the past few years, transcatheter aortic valve replacement has progressively become the treatment of choice for high‐risk patients with severe aortic stenosis. Here, we report the cases of 3 cirrhotic patients who became eligible for liver transplantation after successful transcatheter aortic valve replacement as bridge therapy.  相似文献   
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BackgroundComplementary and alternative medicines have been used to increase comfort and relaxation in mothers during labor. Comforting and preparing the mother in labor can create a positive birth experience. The aim of this study was to evaluate the effect of acupressure on childbirth satisfaction and the experience of giving birth in women with full-term pregnancy, before the onset of labor.MethodsIn 2016, a randomized clinical trial study was conducted in Shahid Akbar Abadi Hospital, Tehran, Iran, enrolling 120 pregnant women at 39–40 gestational weeks with no signs of the onset of labor. They were divided randomly into acupressure, sham acupressure, and control groups. Acupressure points including SP6, BL 60, and BL 32 were pressured bilaterally. Interventions were performed by the researcher, the mother and her relative (husband). Childbirth satisfaction was measured 24 h after delivery. The collected data were analyzed by SPSS software and comparing tests were Chi-squared, Kruskal-Wallis, ANOVA tests (P ≤ 0.05).ResultsThe total childbirth satisfaction did not differ significantly among the three groups (P = 0.460), but the acupressure group had a higher level of satisfaction than the other two groups. Moreover, statistical tests regarding the expectations of the childbirth experience showed a significant difference among the groups (P = 0.033). The actual birth was closest to the expectations of subjects in the acupressure group.ConclusionThis study demonstrated that acupressure may be used as a method in order to attempt to provide a good birth experience and satisfaction of childbirth.  相似文献   
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