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91.
ÁDÁM BÖHM FERENC BÁNYAI KATALIN KOMÁROMY ARNOLD PINTÉR ISTVÁN PRÉDA 《Pacing and clinical electrophysiology : PACE》1998,21(3):629-630
There are only a few reported cases of a pacemaker lead migrating inadvertently into the left atrium or ventricle. An unusual complication of unremoved, unwanted pacemaker lead is presented. The free tip of the lead caused cerebral embolism after perforating the interatrial septum. 相似文献
92.
FAGAN EA; DAVISON FD; TROWBRIDGE R; CARMAN WF; SMITH HM; TEDDER R; WILLIAMS R 《QJM : monthly journal of the Association of Physicians》1991,78(2):123-134
Excluding studies from Brechot and co-workers, little supporthas been found for a role of the hepatitis B virus in the pathogenesisof HBsAg seronegative patients with predominantly chronic liverdiseases, including primary liver cancer. In this study liverDNA from 59 predominantly British patients (four cases withpaired biopsies, 612 months apart) with different, mostlychronic, liver diseases was analysed by molecular hybridization.All were seronegative for HBsAg and serum hepatitis B virusDNA (dot blot hybridization) and their liver diseases were believedto be unrelated to hepatitis B virus infection. Hepatitis Bvirus DNA was detected in liver of 11 (18.6 per cent) patients;nine had episomal(3.2 Kb) DNA and eight had higher molecularweight bands suggesting integrated forms. Six patients werealso seronegative for anti-HBc. Patients of UK and non-UK originwere equally represented. Hepatitis B virus DNA was detectedin serum of six of nine patients tested using the polymerasechain reaction. The detection of hepatitis B virus DNA in liverand in serum by this assay in a significant proportion of patientswith chronic liver disease, hitherto unsuspected of being hepatitisB virus-related, suggests a possible role for this virus inlow- as well as high-prevalence countries. 相似文献
93.
经冠状动脉自体骨髓单个核细胞移植对扩张型心肌病兔心肌组织病理学的影响 总被引:2,自引:2,他引:2
目的:骨髓干细胞在扩张型心肌病动物模型中具有向心肌样细胞和血管内皮细胞分化的潜能。评价经冠脉自体骨髓单个核细胞移植治疗对扩张型心肌病兔心肌组织病理学影响及心功能的变化。方法:实验于2006-09/2007-03在复旦大学附属华山医院心血管研究室完成。①实验材料:3月龄雄性新西兰兔25只,随机数字表法分为正常组5只、模型组10只、冠脉移植组10只。②实验方法:冠脉移植组、模型组兔经耳缘静脉注射盐酸阿霉素建立扩张型心肌病模型。冠脉移植组10只兔麻醉后以髂骨为穿刺点,共采集15mL混有肝素生理盐水的骨髓液,密度梯度离心得到自体骨髓单个核细胞悬液2mL,其中5只兔的骨髓单个核细胞悬液行DAPI标记,经塑性的4F造影导管,模拟临床冠脉内输注细胞悬液。③实验评估:术后4周通过检测血流动力学指标评价心功能的改变;苏木精-伊红、天狼猩红染色观察心肌组织形态学特点,透射电镜观察心肌组织超微结构的改变;TnT间接免疫荧光检测心肌组织DAPI标记情况,以评价骨髓单个核细胞的分化和转归。结果:①血流动力学指标的测定:与基础值比较,细胞移植4周后模型组兔血流动力学指标无明显改变(P>0.05),而冠脉移植组心功能显著改善(P<0.05)。②心肌组织形态学观察:扩张型心肌病兔心肌纤维排列紊乱,坏死区大量淋巴细胞浸润,细胞间隙增宽,心肌间质面积增大。③心肌组织超微结构的变化:造模结束后,模型组心肌细胞线粒体肿胀,肌丝断裂,心肌细胞核呈锯齿状,心肌间质中淋巴细胞浸润,胶原纤维增多。细胞移植4周后,冠脉移植组出现线粒体堆积现象,亦存在巨噬细胞浸润和胶原纤维轻度增生,未发现心肌组织中存在植入的特殊类型细胞。④心肌组织TnT间接免疫荧光检测:DAPI标记的骨髓单个核细胞在心肌组织中富集,血管腔内不存在。结论:①经冠脉自体骨髓单个核细胞移植治疗阿霉素扩张型心肌病兔,利于植入细胞在心肌组织中富集,改善心功能。②透射电镜尚无法证实心肌组织中存在外来的移植细胞。 相似文献
94.
富碘中药海藻对甲状腺细胞凋亡及凋亡调控基因的影响 总被引:1,自引:0,他引:1
目的:通过观察富碘中药海藻对碘缺乏机体甲状腺滤泡上皮细胞凋亡,Fas,FasL,Bcl-2蛋白表达的影响,分析富碘中药过量对甲状腺损伤的机制。方法:实验于2006-03/09在辽宁中医药大学实验中心完成。①实验干预:选用健康鼠龄4周的Wistar大鼠150只。取120只喂低碘饲料建立缺碘大鼠模型,随机分为4组,每组30只:单纯高碘组喂含碘2000μg/L的双蒸水;模型组喂等体积双蒸水;常规剂量海藻组和3倍剂量海藻组分别灌胃海藻生药量13.5g/(kg·d)和40.5g/(kg·d)。以其余30只大鼠为正常对照组:正常饮食,每日灌服等体积双蒸水。②实验评估:分别在给药0,7,28d后取材。采用脱氧核糖核苷酸末端转移酶介导原位缺口末端标记确定甲状腺滤泡上皮细胞凋亡细胞数。采用免疫组化方法观察甲状腺滤泡上皮细胞Fas,FasL,bcl-2表达。结果:大鼠150只均进入结果分析。①凋亡细胞数:给药后7d,常规剂量海藻组和3倍剂量海藻组低于模型组,差异有非常显著性意义(P<0.01)。常规剂量海藻组和3倍剂量海藻组低于单纯高碘组,差异有显著性意义(P<0.05)。给药后28d,正常对照组甲状腺滤泡上皮细胞凋亡细胞数低于其他4组,差异有显著性或非常显著性意义(P<0.05~0.01)。常规剂量海藻组高于单纯高碘组,差异有显著性意义(P<0.05)。②Fas,FasL,Bcl-2蛋白表达:给药7d后,常规剂量海藻组和3倍剂量海藻组Fas蛋白的表达低于模型组,差异有显著性意义(P<0.05)。单纯高碘组和3倍剂量海藻组FasL表达低于模型组,差异有显著性意义(P<0.05)。常规剂量海藻组Bcl-2蛋白表达高于模型组,差异有显著性意义(P<0.05)。给药28d后,单纯高碘组和3倍剂量海藻组Fas蛋白的表达低于模型组,差异有显著性意义(P<0.05)。单纯高碘组、常规剂量海藻组和3倍剂量海藻组Bcl-2蛋白表达高于模型组,差异有显著性意义(P<0.05)。结论:富碘中药海藻给药28d可造成碘缺乏大鼠甲状腺细胞损伤,Fas,FasL,bcl-2可能参与诱导细胞凋亡。 相似文献
95.
Emma Howarth Theresa HM Moore Nicky Stanley Harriet L. MacMillan Gene Feder Alison Shaw 《Health & social care in the community》2019,27(2):271-292
Children who grow up in homes affected by domestic violence and abuse (DVA) are at risk of poor outcomes across the lifespan, yet there is limited evidence on the acceptability and effectiveness of interventions for them. A recent review of child‐focused interventions highlighted a gap in understanding the factors influencing the willingness of parents and children to engage with these programmes. We conducted a systematic review of qualitative evidence on the experiences of receiving and delivering interventions with the aim of identifying factors at different levels of the social–ecological context that may influence parent and child readiness to take up interventions. We searched literature till April 2016 and found 12 reports of eight programmes. Two authors independently screened papers for inclusion, extracted data and identified the first‐ and second‐order constructs. The third‐order constructs were derived and fitted to the ecological framework to inform a picture of readiness to engage with interventions. Three key findings emerged from this review: (a) parent and child readiness is influenced by a complex interplay of individual, relationship and organisational factors, highlighting that individual readiness to take up child‐focussed interventions must be viewed in an ecological context; (b) the specific process through which women become ready to engage in or facilitate child‐focussed interventions may differ from that related to uptake of safety‐promoting behaviours and requires parents to be aware of the impact of DVA on children and to focus on children's needs; (c) there are distinct but interlinked processes through which parents and children reach a point of readiness to engage in an interventions aimed at improving child outcomes. We discuss the implications of these findings for both practice and research. 相似文献
96.
Ramses G Forsyth Gitte De Boeck Johannes J Baelde Anthonie HM Taminiau Dirk Uyttendaele Hendrik Roels Marleen M Praet Pancras CW Hogendoorn 《Journal of bone and mineral research》2009,24(1):70-77
Giant cell tumor of bone (GCTB) is a benign bone tumor with a shown clinical behavior of local recurrences and rare distant metastases. GCTB is composed of uniformly distributed osteoclastic giant cells, thought to originate from the fusion of monocyte–macrophage lineage cells, in a background consisting of mononuclear rounded cells and spindle‐shaped cells. Several reports showed the specific expression of markers, such as CD14 on the mononuclear rounded cell population, however, lacking osteoclastic giant cells. Blood monocytes that were CD14+, CD33+, or CD14+/CD33+ have also been shown to be programmed as pre‐osteoclasts. The macrophage marker CD33 is expressed earlier than CD14 in macrophage maturation, whereas CD14 is expressed longer than CD33. The aim of this study was to investigate CD14/CD33 expression profiles in GCTB. Nineteen GCTB tumor samples of 19 patients were studied. Immunofluorescent analyses were performed with monoclonal antibodies against CD14, CD33, RANK, and CD51. To unambiguously further prove the expression of these molecules, quantitative RT‐PCR was used with subsequent sequencing of its products. All samples showed similar immunoreactivity profiles. The mononuclear rounded cell population was positive for RANK, CD51, CD14, and CD33. The osteoclastic giant cell population expressed RANK and CD51, as well as CD33, but was consistently negative for CD14 expression. The CD14 and CD33 profiles were confirmed by quantitative RT‐PCR. These RT‐PCR products were sequence verified. Osteoclasts in GCTB are the result of fusion of CD33‐expressing pre‐osteoclasts that further fuse with CD14+ mononuclear cells. Although these results reflect a static rather than a dynamic spectrum, we strongly believe that osteoclastogenesis seems not to be the exclusive result of fusion of intratumoral CD14+ mononuclear cells. Moreover, CD33‐modulated osteoclastogenesis opens up the possibility for novel therapeutic directions. 相似文献
97.
Chantal J Leemrijse Marike E de Boer Cornelia HM van den Ende Miel W Ribbe Joost Dekker 《BMC geriatrics》2007,7(1):1-9
Background
Evaluating collaborative community health promotion initiatives presents unique challenges, including engaging community members and other stakeholders in the evaluation process, and measuring the attainment of goals at the collective community level. Goal Attainment Scaling (GAS) is a versatile, under-utilized evaluation tool adaptable to a wide range of situations. GAS actively involves all partners in the evaluation process and has many benefits when used in community health settings.Methods
The purpose of this paper is to describe the use of GAS as a potential means of measuring progress and outcomes in community health promotion and community development projects. GAS methodology was used in a local community of seniors (n = 2500; mean age = 76 ± 8.06 SD; 77% female, 23% male) to a) collaboratively set health promotion and community partnership goals and b) objectively measure the degree of achievement, over- or under-achievement of the established health promotion goals. Goal attainment was measured in a variety of areas including operationalizing a health promotion centre in a local mall, developing a sustainable mechanism for recruiting and training volunteers to operate the health promotion centre, and developing and implementing community health education programs. Goal attainment was evaluated at 3 monthly intervals for one year, then re-evaluated again at year 2.Results
GAS was found to be a feasible and responsive method of measuring community health promotion and community development progress. All project goals were achieved at one year or sooner. The overall GAS score for the total health promotion project increased from 16.02 at baseline (sum of scale scores = -30, average scale score = -2) to 54.53 at one year (sum of scale scores = +4, average scale score = +0.27) showing project goals were achieved above the expected level. With GAS methodology an amalgamated score of 50 represents the achievement of goals at the expected level.Conclusion
GAS provides a "participatory", flexible evaluation approach that involves community members, research partners and other stakeholders in the evaluation process. GAS was found to be "user-friendly" and readily understandable by seniors and other community partners not familiar with program evaluation. 相似文献98.
Amelia K Hausauer Theresa HM Keegan Ellen T Chang Sally L Glaser Holly Howe Christina A Clarke 《BMC medicine》2009,7(1):31
Background
Unprecedented declines in invasive breast cancer rates occurred in the United States between 2001 and 2004, particularly for estrogen receptor-positive tumors among non-Hispanic white women over 50 years. To understand the broader public health import of these reductions among previously unstudied populations, we utilized the largest available US cancer registry resource to describe age-adjusted invasive and in situ breast cancer incidence trends for non-Hispanic white women aged 50 to 74 years overall and by county-level rural/urban and poverty status. 相似文献99.
100.
Fatemi SH King DP Reutiman TJ Folsom TD Laurence JA Lee S Fan YT Paciga SA Conti M Menniti FS 《Schizophrenia Research》2008,101(1-3):36-49
Schizophrenia has a complex genetic underpinning and variations in a number of candidate genes have been identified that confer risk of developing the disorder. We report in the present studies that several single nucleotide polymorphisms (SNPs) and a two-SNP haplotype in PDE4B are associated with an increased incidence of schizophrenia in two large populations of Caucasian and African American patients. The SNPs in PDE4B associated with schizophrenia occur in intronic sequences in the vicinity of a critical splice junction that gives rise to the expression of PDE4B isoforms with distinct regulation and function. We also observed specific decreases in phosphodiesterase 4B (PDE4B) isoforms in brain tissue obtained postmortem from patients diagnosed with schizophrenia and bipolar disorder. PDE4B metabolically inactivates the second messenger cAMP to regulate intracellular signaling in neurons throughout the brain. Thus, the present observations suggest that dysregulation of intracellular signaling mediated by PDE4B is a significant factor in the cause and expression, respectively, of schizophrenia and bipolar disorder and that targeting PDE4B-regulated signaling pathways may yield new therapies to treat the totality of these disorders. 相似文献