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81.
目的 对比分析食管癌病例组与对照组血缘亲属食管癌患病风险,并了解食管癌家族中危险亲属人群患病的新线索.方法 采用病例对照研究方法 ,对食管癌病例组及对照组各720例进行逐层分析,以比较两组各血缘亲属父系、母系食管癌患病危险度(OR)的大小及差异.结果 (1)病例组Ⅰ级亲属食管癌患病危险度(1.34%~2.24%)显著高于对照组(0.78%~1.21%)(P<0.01);Ⅰ级亲属中病例组父母亲食管癌患病危险度为6.11%,显著高于对照组父母亲食管癌患病危险度2.97%(P<0O01).(2)以血缘亲属中父系和母系亲属逐层分析可见,病例组父系食管癌患病危险度(0.87%~1.01%)与母系患病危险度(0.50%~0.79%)均显著高于对照组父系食管癌患病危险度(0.53%~0.65%)与母系患病危险度(0.38%~0.47%)(P<0.05).进一步分析显示,病例组父系中男性亲属与母系中女性亲属,即父系中祖父、父亲、叔伯食管癌患病危险度为2.68%与母系中外祖母、母亲、姨的食管癌患病危险度1.91%均显著高于对照组父系中男性亲属食管癌患病危险度1.50%与母系中女性亲属食管癌患病危险度0.92%(P<0.01).结论 山西省食管癌患者血缘亲属发病危险主要是父亲及其兄弟、母亲及其姐妹,其下代患食管癌风险要大. 相似文献
82.
Further evidence of dopamine transporter dysregulation in ADHD: a controlled PET imaging study using altropane. 总被引:4,自引:0,他引:4
Thomas J Spencer Joseph Biederman Bertha K Madras Darin D Dougherty Ali A Bonab Elijahu Livni Peter C Meltzer Jessica Martin Scott Rauch Alan J Fischman 《Neuropsychopharmacology》2007,62(9):1059-1061
BACKGROUND: The dopamine transporter (DAT) is known to be a key regulator of dopamine, and recent studies of genetics, treatment, and imaging have highlighted the role of DAT in attention-deficit/hyperactivity disorder (ADHD). The findings of in vivo neuroimaging of DAT in ADHD have been somewhat discrepant, however. METHOD: Dopamine transporter binding was measured using a highly selective ligand (C-11 altropane) and positron emission tomography (PET). The sample consisted of 47 well-characterized, treatment-na?ve, nonsmoking, non-comorbid adults with and without ADHD. Additionally, control subjects had few symptoms of ADHD. RESULTS: Results showed significantly increased DAT binding in the right caudate in adults with ADHD compared with matched control subjects without this disorder. CONCLUSIONS: These results confirm abnormal DAT binding in the striatum of adults with ADHD and provide further support that dysregulation of DAT may be an important component of the pathophysiology of ADHD. 相似文献
83.
1 The internal anal sphincter (IAS) has a spontaneous tone and is the main contributor to the maintenance of faecal continence. The spontaneous resting tone exhibited by the sphincter can be modified by neurotransmitters from the autonomic and enteric nervous systems. 2 In this review, the influence of the sympathetic and parasympathetic nervous systems on IAS tone are discussed and the putative roles of nitric oxide, carbon monoxide, vasoactive intestinal peptide and adenosine triphosphate in non‐adrenergic non‐cholinergic transmission are considered. 3 Faecal incontinence is a common condition that places a heavy financial burden on the health service and severely affects patients’ quality of life. Resting anal pressure is reduced in patients with faecal incontinence and agents that increase sphincter tone tend to relieve symptoms. The results of clinical studies of the use of phenylephrine to treat faecal incontinence are reviewed. 4 It is concluded that the IAS is a potential target for drug development for the treatment of faecal incontinence. 相似文献
84.
85.
This paper proposes that an individual's self-assessed health (SAH) does not only suffer from systematic reporting bias and adaptation bias but is also biased owing to confounding health norm effects. Using 13 waves of the British Household Panel Survey covering the period 1991–2005, I show that, while there is a negative and statistically significant correlation between SAH and individuals' own health problem index, this negative effect reduces with the average number of health problems per (other) family member. The relative health bias is small, however, which implies that measures of SAH may not suffer seriously from systematic health norm bias. This is an important finding for researchers working with SAH data as it indicates that we do not have to worry too much about controlling for confounding influences from the health of other household members when estimating SAH regression equations. 相似文献
86.
Marco Antonio Palma Rocio Ortiz Carlos Alvarez-Dardet Maria T. Ruiz 《Social science & medicine (1982)》2009
The possible effect of Government Consumption (a component of Gross Domestic Product (GDP)) on attainment of the hunger Millennium Development Goal (MDG1) was analyzed by evaluating the effect of macroeconomic, social, demographic and policy variables on average undernourished population. Eighty-four developing countries with data available on undernourished population were included in an ecological study. Regression models were applied to explore possible determinants of Undernourished between 1990 and 2004 and consequent achievement of the projected 2004 MDG1. In 2004, 1.4% of the overall undernourished population in the studied countries [70.16 million people] was in excess of the projected level required to meet MDG1. The multiple linear regression showed significant associations between Undernourished and poverty levels, the Gini Index, rural population and Government Consumption. The multiple logistic regression showed significant associations between achievement of projected 2004 MDG1 levels and Government Consumption and the Gini Index. The significant associations between Undernourished and Government Consumption suggest that the effects of GDP components on social conditions call for more thorough research and that policymakers such as governments and international financial institutions need to ensure that changes in distributive and redistributive policies do not negatively affect the possibility of achieving MDG1. 相似文献
87.
血管内皮生长因子在高原脑水肿形成中作用的实验研究 总被引:4,自引:0,他引:4
目的:探讨血管内皮生长因子(VEGF)在高原脑水肿形成中的作用。方法:建立大鼠模拟高原模型,应用脑干湿重比率法定量脑水肿情况、应用荧光素钠透过率测定BBB通透性、应用实时荧光定量RT-PCR法检测脑组织VEGF mRNA含量以及应用蛋白印迹法半定量脑组织VEGF含量。结果:大鼠在高原24 h后脑组织含水率明显增高(P<0.05),荧光素钠透过率显著增加(P<0.01);VEGF mRNA转录及其表达显著增高(P<0.001)。结论:VEGF表达在高原脑水肿形成中起重要作用。 相似文献
88.
Sung Hee Chung Olof Heimbürger Bengt Lindholm Hi Bahl Lee 《Nephrology, dialysis, transplantation》2005,20(6):1207-1213
BACKGROUND: Dialysis patient mortality remains high, and this high mortality may be due to many factors. In peritoneal dialysis (PD) patients, old age, co-morbid diseases, malnutrition, low residual renal function (RRF) and a high peritoneal transport rate have been shown to influence survival, but the relative importance of these factors may differ between different patient populations. Besides, centre practice patterns may differ between centres and may influence patient survival. In addition, the literature suggests that dialysis patient survival may be better in Asian than in Caucasian patients. METHODS: The influence of centre and patient characteristics on patient survival was investigated in 132 Korean and 106 Swedish incident PD patients, who underwent initial biochemical measurements and assessment of adequacy of dialysis, nutritional status, RRF and peritoneal transport characteristics. RESULTS: At the start of PD, Korean patients had a higher prevalence of diabetes, peritoneal Kt/V(urea), peritoneal creatinine clearance and peritoneal fluid removal, and lower body mass index, RRF and dialysate to plasma creatinine concentration ratio (D/P Cr) compared with Swedish patients. Significantly more patients from Korea were placed on temporary haemodialysis before PD (100 out of 132) when compared with Swedish patients (21 out of 106). During the follow-up, there was a significantly higher rate of transfer to other units in Korea and a significantly higher rate of kidney transplantation in Sweden. On Kaplan-Meier analysis, overall patient survival did not differ and relative risk for death was also not different between the two centres even after adjustment for age, diabetes, cardiovascular disease, RRF and D/P Cr. On Cox proportional hazards multivariate analysis, age, diabetes, RRF and D/P Cr were found to be independent predictors of mortality in the combined cohort of patients. While age, diabetes and D/P Cr were independent predictors of mortality in Korean patients, age and RRF independently predicted mortality in Swedish patients. CONCLUSION: Although there were significant differences in centre and patient characteristics, we were unable to confirm a survival advantage for Korean over Swedish PD patients. The results of this study suggest that the reported difference in survival between Asian and Caucasian dialysis patients may have been due, in part, to differences in centre and patient characteristics rather than to race as such. The genetic influence on patient characteristics remains, however, to be elucidated. 相似文献
89.
Ferry Verbaan Inger van Dam Yoshinubu Takakura Mitsuru Hashida Wim Hennink Gert Storm Christien Oussoren 《European journal of pharmaceutical sciences》2003,20(4-5):419-427
The objective of this study was to assess the in vivo fate of poly(2-(dimethylamino)ethyl methacrylate) (pDMAEMA)-based polyplexes after intravenous administration into mice. Circulation kinetics and tissue distribution in terms of plasmid localization and transfection efficiency were assessed. To gain more insight into the observed biodistribution and gene expression profile, the interaction of pDMAEMA-based polyplexes with blood components (erythrocytes and albumin) was investigated in vitro. In the case of i.v. injection of positively charged polyplexes at a dose of 30 microg DNA most of the radioactivity was found in the lungs and the liver 60 min after injection. In the case of pDMAEMA/DNA polyplexes with a negative charge, uptake occurred mainly by the liver. Administration of positively charged complexes at a 30 microg DNA dose resulted in reporter gene expression primarily in the lungs. Injection of negatively charged complexes and naked plasmid did not result in luciferase expression in any of the organs examined. In vitro turbidity experiments showed the induction of a charge dependent aggregation process upon addition of albumin to the polyplexes pointing out to the involvement of aggregate formation in the dominant lung uptake of the positively charged polyplexes. Also, incubations of polyplexes after pre-incubation with a physiological concentration of albumin with washed erythrocytes confirmed that polyplexes induce the formation of extremely large structures. This paper underlines the need for the design of systems with reduced interaction with blood components to promote the delivery of DNA to target tissues outside the lungs. 相似文献
90.
目的 研究腹腔内注射三氧化二砷(arsenic trioxide,As2O3)对小鼠CO2气腹下肝癌H22转移的影响. 方法 昆明鼠40只(清洁级),中腹部穿刺置入1 mm套管针,自套管针注入1×106肿瘤细胞后,建立CO2气腹,压力8 mm Hg,时间30 min.术后随机分4组,每组10只,分别腹腔内注入生理盐水,1 ml;As2O3(2 mg/kg),1 ml;As2O3(4 mg/kg),1 ml;As2O3(4mg/kg)+肝素(10 U/ml),共1 ml.气腹后第3、7天测量肿瘤黏附因子(CD44)、血管内皮生长因子(vascular endothelial growth factor,VEGF)的变化;比较各组生存状态、腹围、体重变化及转移瘤直径.结果 气腹后第3、7天,与对照组相比,各As2O3组CD44、VEGF表达均明显降低(P<0.05).2个高剂量组的气腹后第3天VEGF、第7天CD44比低剂量组降低明显(P<0.05).4组戳口种植率分别为9/10、8/10、7/10、6/10,差异无显著性(x2=2.667,P=0.446). 结论 As2O3对CO2气腹腹腔镜肿瘤生长转移有抑制作用. 相似文献