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1.
Discrimination of well-differentiated pulmonary adenocarcinoma from reactive bronchioloalveolar epithelium can be difficult on routine histology, especially with small biopsies. Ancillary studies to help in this distinction are desirable. p63, a p53-homologous nuclear protein, is a marker of reserve cells of the bronchus and terminal lobular unit. In this study, 33 cases of adenocarcinoma (20 open lung and 13 transbronchial/percutaneous biopsies) and 43 cases of benign lungs with fibrosis and metaplasia (22 open lung and 21 transbronchial/percutaneous biopsies) were studied for nuclear p63 expression by immunohistochemistry (Dako, Carpinteria, CA, USA). Five additional cases each of atypical adenomatous hyperplasia and adenosquamous carcinoma and three cases of squamous carcinoma (all open lung biopsies) were also stained. The diagnostic categories of benign lung conditions were usual interstitial pneumonia, parenchymal scar, cryptogenic organizing pneumonia and diffuse alveolar damage. In neoplastic cases, p63 positivity was calculated as percentage of all tumor cells examined. In areas of normal lung, p63 decorated the reserve cells of large and small airways and occasional cells of the distal lobular unit. In fibrotic reactive processes, an interrupted but distinct pattern of nuclear staining was present in all cases, with staining of basal cells of the airways as well as bronchiolar- and squamous-metaplastic epithelium (43/43, 100%). p63 immunoreactivity was less uniform in areas of acute lung injury within these cases. One adenocarcinoma and two cases of atypical adenomatous hyperplasia showed strong immunoreactivity (>80%), while three adenocarcinomas highlighted only rare tumor nuclei (<5% of tumor cells). Morphologic areas where p63 immunostaining was not helpful included the junction of normal lung and lepidic growth of adenocarcinoma, and retrograde spread of adenocarcinoma into small airways. Our results highlight the differential expression of p63 across various bronchioloalveolar lesions. Moreover, p63 may be helpful in distinguishing reactive from neoplastic glandular proliferations in the lung. 相似文献
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Wasim Jafri Khalid Mumtaz William P Burdick Page S Morahan Rosslynne Freeman Tabassum Zehra 《BMC medical education》2007,7(1):34
Background
Residents play an important role in teaching of medical undergraduate students. Despite their importance in teaching undergraduates they are not involved in any formal training in teaching and leadership skills. We aimed to compare the teaching skills of residents with faculty in facilitating small group Problem Based Learning (PBL) sessions. 相似文献3.
Sexuality and Disability - This study was carried out to determine the reproductive health, sexual function and sexual satisfaction levels of women with disabilities. The sample of the study was... 相似文献
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Zehra N. Pamuklar Jiegen Chen Michael Muehlbauer Anna Spagnoli Alfonso Torquati 《Surgery for obesity and related diseases》2013,9(1):94-99
BackgroundThe insulin-like growth factor-1 (IGF-1) signaling pathway promotes adipocyte differentiation and, therefore, insulin sensitivity by suppression of necdin expression, which represses peroxisome proliferator-activated receptor-gamma promoter activity by interaction with E2F4 in mouse adipocytes. The aim of the present study was to test the hypothesis that this pathway represents one of the mechanisms by which Roux-en-Y gastric bypass surgery (RYGB) induces resolution of insulin resistance.MethodsClinical samples were collected and the key biomarkers measured to test the hypothesis that the IGF-1 pathway represents 1 of the mechanisms by which RYGB induces resolution of insulin resistance in obese individuals.ResultsFree IGF-1 levels were significantly greater in the post-RYGB patients than in the pre-RYGB obese patients (2.55 ± 1.54 versus 1.32 ± .65 μg/L, P = .03) and similar to that in normal weight controls (2.54 ± 1.27 μg/L). Necdin and E2F4 gene expression in the adipose tissue was significantly downregulated after RYGB compared with obese and were similar to the levels observed in the controls. In mature human adipocytes cultured in vitro, treatment with des-IGF-1 induced downregulation of necdin and E2F4 gene expression in a dose-dependent manner (P = .01).ConclusionAfter RYGB, the insulin/IGF-1 signaling pathway is activated and could account for the observed decrease in the expression of necdin, which represses peroxisome proliferator-activated receptor-gamma promoter activity by interaction with E2F4. This could represent one of the mechanisms that induce resolution of insulin resistance after RYGB. 相似文献
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Yelda Tayyareci M.D. Selen Yurdakul M.D. Gulsah Tayyareci M.D. Yilmaz Nisanci F.E.S.C. Berrin Umman M.D. Zehra Buğra M.D. 《Echocardiography (Mount Kisco, N.Y.)》2010,27(10):1211-1218
Aim: In diabetes mellitus (DM) patients, left ventricular dysfunction is widely evaluated and established by conventional diagnostic methods, whereas right ventricular (RV) function is not as sufficiently evaluated. The aim of this study is to assess the preclinical effects of DM on RV function by using novel Tissue Doppler Imaging (TDI)‐derived indices. Methods: The study included 96 patients with type II DM [60 with DM only and 36 patients with coexisting DM and hypertension (DMHT)] and 40 healthy controls. Conventional parameters and TDI‐derived systolic velocities of tricuspid annulus [isovolumic myocardial acceleration (IVA), peak myocardial velocity during isovolumic contraction (IVV), peak systolic velocity during ejection period (Sa), RV Tei index] were measured. Results: TDI‐derived RV IVA was significantly lower in both DM and DMHT patients compared to controls indicating subclinical impairment in RV systolic function in the study patients (P = 0,0001). However RV IVA was similar in DM and DMHT subgroup supporting RV systolic impairment in DM was independent from HT. In correlation analysis, RV IVA was significantly correlated with the existence of diabetic nephropathy (r =?0,38; P = 0,003), retinopathy (r =?0,35; P = 0,006), insulin resistance (r =?0,52; P = 0,0001). Conclusions: Diabetes is associated with subclinical RV systolic dysfunction, regardless of coexisting hypertension. Tissue Doppler‐derived IVA; is a novel, non‐invasive parameter which may be used in early detection of RV systolic dysfunction in patients with DM. (Echocardiography 2010;27:1211‐1218) 相似文献
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Kasikcioglu E Oflaz H Akhan H Kayserilioglu A Mercanoglu F Umman B Bugra Z 《Heart and vessels》2004,19(4):183-188
The aim of this study was to determine left ventricular (LV) morphology and aortic function in power athletes and to compare them with normal subjects. Thirty-two elite male wrestlers and 15 age-matched healthy male controls were included. All subjects underwent echocardiographic examination. Measurements included LV cavity dimension at systole and diastole, wall thickness, diastolic parameters, and aortic diameter, 3cm above aortic valve, at systole and diastole. Left ventricular mass and mass index were found to be higher in the athletes than in control subjects. The aortic distensibility index was found to be reduced in the athletes compared with controls (2.53 ± 0.91 vs 3.94 ± 1.77cm2dyne–1 10–6, P = 0.003), while the aortic stiffness index was significantly higher in the athletes than in controls (9.12 ± 3.23 vs 6.65 ± 2.35, P = 0.02). However, LV end-systolic wall stress was lower in the athletes than in controls. Furthermore, transmitral early (E) and late (A) peak velocity, peak velocity of the myocardial systolic wave (S
m), and early (E
m) and atrial (A
m) diastolic waves at the inferior wall were higher in the athletes than in controls. Reduced aortic distensibility in elite power athletes may be one of the cardiovascular adaptation factors which affect LV hypertrophy. 相似文献
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