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31.
Regulations evolve and risks management becomes one of the biomedical engineers' preoccupations. Thus, risks are various, and consequently it is difficult to identify, to manage and to bring them under control. Furthermore, regulations exist for sectors like healthcare technology monitoring, but it is not the same thing for instance for the risks linked to the maintenance. Thus regulation in the sector of maintenance evolves and the decree of the 1st July law of health safety is going to modify the biomedical environment. The goal of this work is to study the tools and the methods of risks management that have been used for several years in the industrial field and to use them for some biomedical equipment like monitors or IV pumps. These methods adapted to these equipment will allow us to determine some appropriate rules of maintenance. 相似文献
32.
年龄与代谢综合征的关系及防治对策 总被引:1,自引:0,他引:1
目的了解中老年人群年龄与多种代谢异常的聚集状况,为心脑血管疾病的一级预防提供依据。方法对744例中老年人按不同年龄分为5组,分析代谢综合征(MS)各项指标的变化规律及特点。结果年龄与肥胖呈明显负相关(P<0.001),与高血糖、高血压及冠心病、脑卒中呈明显正相关(P<0.05或0.001);40~60岁组MS的患病率基本一致,约为30%,70岁以后明显增加,到80岁时可高达51%(P<0.05或0.01);MS与冠心病和脑卒中的患病率均明显相关(P<0.05),随着临床指标个数的增加,冠心病的患病率增加了6.8%,脑卒中的患病率增加了7.44%。结论中年人群超重或肥胖的患病率明显高于老年组,应引起足够重视;随着年龄增长,代谢异常指标数目增多,尤其是≥3项指标的人数明显增加;MS作为心血管危险因素直接导致冠心病、脑卒中发病率增加。针对中老年人群MS的特点,制定相应的干预措施十分重要。 相似文献
33.
AIMS: To assess the relationship between neighbourhood deprivation and the rate of gestational diabetes mellitus (GDM) using routinely collected data from a clinical information system, in Plymouth, UK. METHODS: Between 1 January 1996 and 31 December 1997, 3933 women residing within the Plymouth Primary Care Trust (PCT) were screened for GDM using indices of neighbourhood deprivation and prevalence of GDM. Areas (n = 43) were classified according to the Townsend index, measuring material deprivation. Pregnant women with and without GDM were compared. RESULTS: The prevalence of GDM was 1.7%[95%, confidence interval (CI) 1.20, 2.11]. The prevalence of GDM ranged from 1.05% (95% CI 0.60, 1.70) in the most deprived to 2.10% (95%, CI 1.34, 3.13), in the least deprived neighbourhood. Crude rates decreased by 50%[relative prevalence (RP) (95% CI) 0.50 (0.27, 0.94); P = 0.06] amongst those living in the most-deprived compared with those living in the least-deprived areas. Using a stepwise binary logistic regression model, older age at delivery significantly increased the risk of developing GDM. [RP (95%, CI) 1.09, (1.04, 1.13)]. Townsend deprivation score had no significant independent association with GDM when other covariates were considered. CONCLUSION: These data suggest that the neighbourhood context in which women live has no impact on the risk of GDM. Diabet. 相似文献
34.
C. Fischer W. Gross J. Krüger M. Cremer F. Vogel T. Grimm 《Annals of human genetics》2006,70(2):237-248
For several genetic diseases two biological phenomena have been recognised as important: germline mosaicism; and different new mutation rates in males and females depending on mutation type. Both principles have been investigated separately and their influence on risk estimation in families has been exemplified in the literature. The aim of this paper is to present a general model that includes mosaicism and different new mutation rates. Mosaicism is introduced by defining additional alleles at the disease locus in combination with adapted segregation rules. Taking Duchenne muscular dystrophy as an example, we derive the conditions which have to be fulfilled for a population in mutation selection equilibrium. Our approach describes the model at the population level and not in individual subjects. This has the advantage of being able to use well known algorithms for the calculation of likelihoods in pedigrees, and to include additional diagnostic information such as marker genotypes and carrier deletion test results. We demonstrate the impact of the new model on a typical pedigree. In families where the patient is not available, the distinction between point mutations and deletions is important, since often molecular diagnostic tests for females can only screen for deletions. Negative deletion test results can now be included in the risk calculations. 相似文献
35.
36.
肥胖类型与脑卒中亚型的相关性研究 总被引:1,自引:0,他引:1
目的探讨肥胖类型与脑卒中亚型的相关性。方法将573例急性脑卒中患者分为脑出血组126例,脑梗死组447例,脑梗死组再分为脑血栓形成组(215例)和腔隙性脑梗死组(232例),另外选择277例无脑卒中者为对照组。测量腰围、臀围和体重,计算体重指数和腰臀比(WHR),分析肥胖参数与脑卒中各亚组的关系。结果脑卒中各亚组与对照组肥胖发生率差异无显著性意义(P>0.05);各组WHR明显大于对照组(P<0.05)。WHR增大明显增加脑卒中各亚组的危险性(P<0.05);女性腹围增大患腔隙性脑梗死危险性升高(P<0.05);男性体重增加患脑出血的危险性升高(P<0.01)。结论腹型肥胖是脑出血、脑血栓形成和腔隙性脑梗死的危险因素之一。 相似文献
37.
Non-alcoholic fatty liver disease, the metabolic syndrome and the risk of cardiovascular disease: the plot thickens. 总被引:5,自引:0,他引:5
G Targher 《Diabetic medicine》2007,24(1):1-6
Non-alcoholic fatty liver disease (NAFLD) affects a substantial proportion of the general population and is frequently associated with many features of the metabolic syndrome (MetS). Currently, the importance of NAFLD and its relationship with the MetS is being increasingly recognized, and this has stimulated an interest in the possible role of NAFLD in the development of atherosclerosis. Recent studies have reported the association of NAFLD with multiple classical and non-classical risk factors for cardiovascular disease (CVD). Moreover, there is a strong association between the severity of liver histopathology in NAFLD patients and greater carotid artery intima-media thickness and plaque, and lower endothelial flow-mediated vasodilation (as markers of subclinical atherosclerosis) independent of obesity and other MetS components. Finally, it has recently been demonstrated that NAFLD is associated with an increased risk of all-cause death and predicts future CVD events independently of other prognostic factors, including MetS components. Overall, therefore, the evidence from these recent studies strongly emphasizes the importance of assessing the global CVD risk in patients with NAFLD. Moreover, these novel findings suggest a more complex picture and raise the possibility that NAFLD, as a component of the MetS, might not only be a marker but also an early mediator of CVD. 相似文献
38.
P. Neary C. Hurson D. O. Briain A. Brabazon D. Mehigan T. V. Keaveny S. Sheehan 《Colorectal disease》2007,9(2):166-172
OBJECTIVE: Colonic infarction is a recognized complication of abdominal aortic aneurysm (AAA) surgery. The clinical difficulty in establishing the diagnosis combined with the patient's poor physiological status is usually associated with a fatal outcome. We assessed our experience with this problem to identify a possible risk factor profile for these patients. METHOD: Patients records were identified from the operative logs, intensive care unit, Hospital Inpatient Enquiry system and vascular unit databases over a 6-year period. RESULTS: A total of 405 patients underwent AAA repair during this period; 140 as emergency ruptures. Nine patients were identified from the databases with known colonic infarction (2.2%). One was a woman. The mean age was 70 years. Seven patients had emergency ruptures (5%). Twenty independent risk factors were analysed using univariate and multivariate logistic regression models. Significant risk factors identified by using a multivariate analysis included the nature of the presenting patient, preoperative hypotension, prolonged cross-clamp time, intra-operative ischaemia and postoperative acidosis. Confirmatory diagnosis was made by colonoscopy in eight patients. One patient survived following the salvage surgery. The mean duration of survival was 10.5 days. The overall mortality was 89% of patients. CONCLUSION: In our unit infrarenal AAA repair has a 2.2% rate of colonic infarction. A definitive diagnosis is best made by colonoscopy. A risk factor profile for the development of colonic infarction may be constructed on the basis of specific clinical parameters. Earlier intervention on the basis of this profile may ultimately reduce the current excessive mortality. 相似文献
39.
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
40.