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目的:建立鼠巨细胞病毒(MCMV)感染C57BL/6小鼠急性肝炎模型并对其感染特点进行分析及鉴定。方法:将24 只C57BL/6小鼠随机分为阴性对照组(n =12)及病毒感染组(n =12),病毒感染组腹腔注射1.0×106 PFU(200 μL)MCMV悬液,阴性对照组注射等体积小鼠胚胎成纤维细胞(MEF)悬液。于感染后第3天和第7天取外周血分离血清检测谷丙转氨酶(ALT)及谷草转氨酶(AST)。同时进行肝组织病毒分离、组织病理学及MCMV IE和M55基因、细胞因子白细胞介素-6(IL-6)、白细胞介素-1β(IL-1β)、肿瘤坏死因子α(TNF-α)的检测。结果:病毒感染组肝组织匀浆病毒分离均为阳性,肝炎发生率为100%。在感染后第3天即发生肝炎病理改变,病毒感染组血清ALT及AST较阴性对照组明显升高(P <0.01);病毒感染组肝脏HE染色第3天可见局灶性炎性细胞浸润及肝脏点灶状坏死,持续至第7天,Ishak评分较阴性对照组明显升高(P <0.01);在感染后第3天病毒感染组肝组织内可检测到MCMV IE及M55基因,且在感染后第7天仍可测得IE基因;感染后第3天及第7天病毒感染组炎性细胞因子IL-6、TNF-α及IL-1β mRNA表达水平明显升高(P <0.05)。 结论:成功建立MCMV感染C57BL/6小鼠急性动物肝炎模型,其感染表现主要集中在急性感染前期。  相似文献   
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Determining aortic stenosis (AS) severity is clinically important. Calculating aortic valve (AV) area by means of the continuity equation assumes a circular left ventricular outflow tract (LVOT). The full impact of this assumption in calculating AV area is unknown. Predictors of noncircular LVOT shape in patients with AS are undefined.In 109 adult patients with AS who underwent multiplanar transesophageal echocardiography, we calculated AV area by means of the standard continuity method and by a modified method involving planimetric LVOT area.We found 54 circular, 37 horizontal-oval, 8 vertical-oval, and 10 irregular LVOTs. Area derived by direct planimetry correlated better with the modified than the standard continuity method (r=0.89 vs r=0.85; both P=0.0001). Valve areas of patients with mild, moderate, or severe AS by planimetry were more often mischaracterized with use of the standard than modified method (29 vs 18; P <0.0001). Horizontal-oval AV area derived by planimetry (1.28 ± 0.55 cm2) was underestimated by the standard method (1.05 ± 0.47 cm2; P=0.001), but not by the modified method. Congenital AV morphology and low cardiac index were the only multivariate predictors of horizontal-oval shape. Low cardiac index was the only predictor of noncircular shape.More than half our patients with AS had noncircular LVOTs. Using the modified method reduces mischaracterizations of AS severity. Congenital AV morphology and low cardiac index predict horizontal-oval or noncircular shape. These data suggest the value of direct LVOT measurement to calculate AS severity in patients who have congenital AV or a low cardiac index.  相似文献   
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Urothelial cell carcinoma (UCC) of the bladder is one of the most common malignancies, causing considerable morbidity and mortality worldwide. It is unique among the epithelial carcinomas as two distinct pathways to tumourigenesis appear to exist: low grade, recurring papillary tumours usually contain oncogenic mutations in FGFR3 or HRAS whereas high grade, muscle invasive tumours with metastatic potential generally have defects in the pathways controlled by the tumour suppressors p53 and retinoblastoma. Over the last two decades, a number of transgenic mouse models of UCC, containing deletions or mutations of key tumour suppressor genes or oncogenes, have helped us understand the mechanisms behind tumour development. In this summary, I present my work investigating the role of the WNT signalling cascade in UCC.  相似文献   
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ObjectiveClinical specialty societies recommend long-acting reversible contraceptives (LARCs) as first-line contraception for adolescent women. We evaluated whether a combined educational and process improvement intervention enhanced LARC placement in primary care within an integrated health care system.MethodsThe intervention included journal clubs, live continuing education, point-of-care guidelines, and new patient materials. We conducted a retrospective cohort study across 3 time periods: baseline (January 2013?September 2015), early implementation (October 2015–March 2016), and full implementation (April 2016–June 2017). The primary outcome was the proportion of LARCs placed by primary care clinicians among women aged 13 to 18 years compared with gynecology clinicians.ResultsKaiser Foundation Health Plan of Colorado cared for approximately 20,000 women aged 13 to 18 years in each calendar quarter between 2013 and 2017. Overall, LARC placement increased from 7.0 per 1000 members per quarter at baseline to 13.0 per 1000 during the full intervention. Primary care clinicians placed 6.2% of all LARCs in 2013, increasing to 32.1% by 2017 (P < .001), including 45.5% of contraceptive implants. Clinicians who attended educational sessions were more likely to adopt LARCs than those who did not (17.9% vs 6.4% respectively, P = .009). Neither overall LARC placement rates (relative risk, 1.9; 95% confidence interval, 0.7?5.6) nor contraceptive implant rates (relative risk, 3.0; 95% confidence interval, 0.9?9.8) increased significantly in clinicians who attended educational activities.ConclusionsThis multimodal intervention was associated with increased LARC placement for adolescent women in primary care. The combination of education and process improvement is a promising strategy to promote clinician behavior change.  相似文献   
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《Clinical neurophysiology》2019,130(9):1562-1569
ObjectiveConventional deep brain stimulation (DBS) systems with ring-shaped leads generate spherical electrical fields. In contrast, novel directional leads use segmented electrodes. Aim of this study was to quantify the impedance variations over time in subjects with the directional Cartesia-Boston® system.MethodsImpedance records, programming settings, and clinical data of 11 consecutive Parkinsonian patients implanted with DBS directional leads in two Italian centers (Udine and Vicenza) were retrospectively evaluated. Data were collected before starting stimulation (in the operating room and at days 5 and 40) and after switching stimulation on at the successive follow-up visits (1, 6 and 12 months).ResultsDirectional leads have significantly higher impedance than ring leads. Stimulated contacts had always lower impedance compared to non-stimulated contacts. Before DBS-on, all contacts had higher impedance in the operating room, with an initial decrease five days post-surgery and a subsequent increase at day 40, more evident for directional contacts. The impedance of directional leads increased post-implantation at 1 and 6 months with a plateau at 12 months.ConclusionsThere was a significant difference between the directional and ring leads at baseline (before activation of DBS) and during follow-up (chronic DBS).SignificanceOur study reveals new information about the impedance of segmented electrodes that is useful for patient management during the initial test period, as well as during long-term DBS follow-up.  相似文献   
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