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41.
采用LabVIEW技术完成对心电、呼吸、无创血氧和无创血压信号的采集与处理,而后通过MATLAB模糊测量系统对采集的人体生理信号进行模糊预测分析。通过实验检验了人体生理信号检测、处理和模糊预测分析方法的可靠性。LabVIEW技术对人体生理信号的模糊预测分析是有效的,可用于检测阻塞性睡眠呼吸暂停患者的生理状态信号。 相似文献
42.
目的 分析急性缺血性卒中患者(acute ischemic stroke,AIS)住院期间消化道出血(gastrointestinal
bleeding,GIB)的发生率、发生时间及危险因素。
方法 本研究纳入首都医科大学附属北京天坛医院急性卒中院内并发症队列(inhospital medical
complication after acute stroke,iMCAS)研究中AIS患者。收集患者临床信息,根据住院期间是否发生
GIB分为GIB组和无GIB组,采用多因素Logistic回归模型,分析AIS患者发生GIB相关危险因素。
结果 共纳入1129例AIS患者,平均年龄58.7±12.5岁,女性230例(20.4%)。47例住院期间发生GIB,
发生率为4.2%,卒中发作至GIB确诊时间为5(3~13)d。合并肝硬化(OR 10.06,95%CI 2.44~41.38)、
高入院NIHSS评分(OR 1.13,95%CI 1.08~1.19)、高白细胞计数(OR 1.25,95%CI 1.13~1.38)、住院时
间长(OR 1.05,95%CI 1.01~1.10)是AIS患者发生消化道出血的独立危险因素。
结论 本单中心研究数据提示合并肝硬化、高入院NI HSS评分、高白细胞计数、住院时间长是AI S患
者住院期间发生GIB的独立危险因素。 相似文献
43.
目的 分析卒中高危人群糖化血红蛋白与颈动脉粥样硬化斑块的关系。
方法 2018年5-6月由孝感市中心医院按整群随机抽样方法,随机抽取孝感市城乡各1个社区居民
进行筛查,通过问卷调查、体格检查、实验室检查、颈部血管超声检查筛选卒中高危人群纳入研究。
根据颈动脉超声检测结果将卒中高危人群分为非斑块组和斑块组(颈动脉)。分别采用单因素和多
因素Logistic回归,分析糖化血红蛋白与颈动脉斑块的关系,并根据年龄(60岁)、BM(I 24 kg/m2)、是
否有高血压对研究人群进行分层分析,研究不同特征的卒中高危人群中糖化血红蛋白与颈动脉斑块
的关系。
结果 最终纳入卒中高危人群629例,男性338例(53.74%),平均54.85±8.97岁,糖化血红蛋白平
均浓度为4.70%±1.02%。其中斑块组患者215例(34.18%),非斑块组患者414例(65.82%)。与非斑
块组患者相比,斑块组患者男性、卒中、TIA、高血压、超重患者比例更高,年龄更大,BMI、血压、空
腹血糖、糖化血红蛋白、TC水平更高(均P<0.01)。校正其他危险因素后,糖化血红蛋白是颈动脉
粥样硬化斑块发生的独立影响因素(每升高1%,OR 1.16,95%CI 1.01~1.31,P =0.018)。分层分析显
示,年龄≥60岁(OR 1.48,95%CI 1.09~2.01,P =0.016)、BMI≥24 kg/m2(OR 1.97,95%CI 1.07~3.64,
P =0.030)、高血压人群(OR 1.31,95%CI 1.06~1.62,P =0.013)中糖化血红蛋白均是颈动脉斑块发生
的独立危险因素。
结论 卒中高危人群糖化血红蛋白与颈动脉斑块的发生密切相关,特别是在年龄≥6 0岁、
BMI≥24 kg/m2和高血压人群中。 相似文献
44.
45.
Inter-cohort differences in coronary heart disease mortality in the 25-year follow-up of the seven countries study 总被引:2,自引:0,他引:2
A. Menotti A. Keys D. Kromhout H. Blackburn C. Aravanis B. Bloemberg R. Buzina A. Dontas F. Fidanza S. Giampaoli M. Karvonen M. Lanti I. Mohacek S. Nedeljkovic A. Nissinen J. Pekkanen S. Punsar F. Seccareccia H. Toshima 《European journal of epidemiology》1993,9(5):527-536
Sixteen cohorts of men aged 40–59 years at entry were examined with the measurement of some risk factors and then followed-up for mortality and causes of death for 25 years. These cohorts were located in the USA (1 cohort), Finland (2), the Netherlands (1), Italy (3), the former Yugoslavia (5), Greece (2), and Japan (2), and included a total of 12,763 subjects.Large differences in age-adjusted coronary heart disease (CHD) death rates were found, with extremes of 45 per 1000 in 25 years in Tanushimaru, Japan, to 288 per 1000 in 25 years in East Finland. In general, higher rates were found in the US and Northern European cohorts as compared to the Southern European and Japanese cohorts. However, during the last 10 years of follow-up large increases of CHD death rates were found in some Yugoslavian areas. Out of 5 measured entry characteristics treated as age-adjusted levels (serum cholesterol, systolic blood pressure, cigarette smoking, body mass index and physical activity at work), only serum cholesterol was significant in explaining cohort differences in CHD death rates.Over 50% of the variance in CHD death rates in 25 years was accounted for by the difference in mean serum cholesterol. This association tended to decline with increasing length of follow-up, but this was due to the great changes in mean serum cholesterol in the two Jugoslavian cohorts of Velika Krsna and Zrenjanin. When these two cohorts were excluded the association increased with time.Changes in mean serum cholesterol between year 0 and 10 helped in explaining differences in CHD death rates from year 10 onward.It can be concluded that this study suggests that mean serum cholesterol is the major risk factor in explaining cross-cultural differences in CHD. 相似文献
46.
The complexity of the RHD and RHCE genes, which is the greatest of all blood group systems, confounds analysis at the molecular level. RH DNA typing was introduced in 1993 and has been applied to prenatal testing. PCR-SSP analysis covering multiple polymorphisms was recently introduced for the screening and initial characterization of partial D. Our objective is to summarize the accrued knowledge relevant to the approaches to Rh phenotype prediction by DNA typing, their possible applications beyond research laboratories and their limitations. The procedures, results and problems encountered are highly detailed. It is recommended that DNA typing comprises an analysis of more than one polymorphism. We discuss future directions and propose a piecemeal approach to improve reliability and cost-efficiency of blood group genotyping that may eventually replace the prevalent serology-based techniques even for many routine tasks. Transfusion medicine is in the unique position of being able to utilize the most extensive phenotype databases available to check and develop genotyping strategies. 相似文献
47.
参考缓和加氢裂化(MHC)反应机理,开发了一种既能预测产品产率,又能预测产品性质的MHC动力学网络模型。以文献上发表的MHC实验数据为例,进行了参数估计,确定了动力学参数,给出了模型的标准差。本模型所预测的MHC结果,与文献数据吻合良好,具有良好的预测性能。 相似文献
48.
Katherine A. Vittes Ph.D. Susan B. Sorenson Ph.D. 《The Journal of adolescent health》2006,39(6):929-932
In a survey of 5657 community-residing adolescents, those who said they could get a handgun in two days reported similar and those who said they could not get a handgun reported fewer risk behaviors and less violence perpetration and victimization than adolescents who have their own handgun. Adolescents who said they could get a handgun reported more exposure to and experience with firearms than those who said they could not get a handgun. Risk reduction efforts regarding adolescents should be expanded to include adolescents who say they can get a handgun. 相似文献
49.
The use of oral implants opened a wide range of prosthetic treatment possibilities in edentulous patients. Although the reported
success rates of oral implants are high, failures do occur. This paper reviews the current knowledge about the aetiology,
the signs and symptoms and the possible influencing factors of implant failure. Possible causes of implant failure are thought
to be infection of the periimplant tissues, occlusal overload, or a combination of both. Nevertheless, pinpointing one of
these as the aetiological factor in a particular case is difficult and should be handled reluctantly. Although the cause might
seem obvious, influencing factors could play a role as well. Gaining insight into these processes might stimulate the adoption
of preventive action and therefore increase the predictability of the treatment outcome with oral implants.
Received: 4 April 1997 / Accepted: 27 November 1997 相似文献
50.
合肥地区献血员感染HBV和HCV危险因素的多因素分析 总被引:2,自引:0,他引:2
用ELISA法检测了合肥地区1440名献血员抗HCV和乙肝五项指标,抗HCV阳性率为55%;HBsAg携带率为15%,HBV总感染率437%。分别以抗HCV阳性与感染过HBV的献血员为病例,以抗HCV阴性与未感染HBV的献血员为对照进行了HCV和HBV感染危险因素的单因素和多因素分析。结果显示,ALT、献血次数、献血量、文化程度、献血员心理和输血史与HCV感染有关;血型、家庭人口数和家庭子女数与HBV感染有关。 相似文献