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21.
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S P Caudill  S J Smith  G R Cooper 《Statistics in medicine》1989,8(3):295-309; discussion 331-2
Using data from the National Health and Nutrition Examination Survey (NHANES II) 1976-1980, we demonstrate how cross-sectional total serum cholesterol surveillance data can be used by an individual to assess current and future personal cholesterol risk status. We propose statistical models, based on a person's current measured cholesterol level and the relationship between cross-sectional age and cholesterol percentile estimates, that will allow prediction of future cholesterol levels or the age at which specified cholesterol risk levels will be reached if no cholesterol-altering intervention is taken. These models incorporate the observed variation in the NHANES II data and expected intraperson biological variation and intralaboratory analytical variation. We illustrate the adequacy of the models using data from the longitudinal Framingham Study.  相似文献   
23.
鼻咽癌高危人群微核特征研究   总被引:1,自引:0,他引:1  
目的 观察鼻咽癌高危人群的主要细胞遗传学特征。方法 常规培养外周血淋巴细胞,检测鼻咽癌高危人群、鼻咽癌患者、鼻咽炎患者及正常人的微核率。结果 鼻咽癌高危人群及鼻咽癌患者的微核率明显增加,且随病情进展而继续增高。结论 鼻咽癌高危人群存在比较明确的细胞遗传不稳定性。  相似文献   
24.
围生期窒息发生率和死亡率近10年变迁及相关因素   总被引:2,自引:1,他引:1  
目的 分析近10年来围生期窒息发生率和死亡率的变迁,探讨围生期窒息相关因素及开展新法复苏对围生期窒息发生率和死亡率的影响。方法对近10年郑州大学第三附属医院分娩的所有活产新生儿的病历资料进行回顾性分析,计算窒息的发生率、死亡率、病死率,观察上述指标的逐年变化趋势及季节变化的情况,并探讨性别、双/多胎、出生体质量、胎龄分娩方式对这些指标的影响。结果轻度窒息发生率在开展新法复苏后明显下降,并稳定在1.5%左右,而重度窒息的发生率和病死率均无明显变化。窒息儿的发生率以4月份最高,但死亡率和病死率以7月份最高。窒息的发生还与性别、双/多胎、出生体质量、早产以及阴道助产有关。结论围生期窒息的发生与性别、双/多胎、出生体质量、胎龄密切相关;新法复苏能显著降低轻度窒息的发生率,对重度窒息的发生率和窒息病死率无明显影响;窒息儿的死亡率和病死率与季节有关。  相似文献   
25.
Alzheimer's disease (AD) is a neurodegenerative disorder with mixed cognitive and behavioural clinical manifestations. The possession of apolipoprotein-E (ApoE) epsilon4 allelic variant is one of the most important risk factors for developing late-onset AD (LOAD). In this study we analysed the relationship between the entire range of behavioural symptoms, cognitive deficit, and sociodemographic characteristics and ApoE epsilon4 allele possession with multivariate logistic regression models in LOAD patients. Patients included (n = 171) were consecutively admitted in a memory clinic for the first diagnostic visit. Levels of behaviour and cognition within the last month were assessed by the Neuropsychiatric Inventory and Mini Mental State Examination. Presence of clinically significant psychosis, delusions and hallucinations at the early stage of the illness, from the onset to the first visit, was measured with diagnostic criteria. ApoE epsilon4 allele possession was associated with increased levels of delusions within the last month from the first visit (OR 1.23; 95% CI 1.01-1.50; P < 0.05) and with the presence of categorical delusions at the early stage until the first visit (OR 3.11; 95% CI 1.21-8.01; P < 0.02). In this study, which considers the entire range of behavioural expressions in LOAD patients at the early stage of the illness, the relationship between behaviour and ApoE epsilon4 allele is confirmed for delusions only.  相似文献   
26.
27.
To determine the prevalence of excessive daytime sleepiness (EDS) and that of dozing and sudden onset of sleep episodes (SOS) while driving in ambulatory patients with Parkinson's disease (PD) in France, a national sample of private and public neurologists was asked to recruit the first 10 consecutive nondemented PD patients. Each patient completed a questionnaire including the Epworth Sleepiness Scale (ESS) and the likelihood of dozing off and experiencing SOS episodes behind the wheel. Clinical and demographic data were collected. One thousand six hundred and twenty‐five patients with PD were included in the survey. Twenty‐nine percent of the patients suffered from EDS (ESS score ≥10) but only 0.8% declared a high chance of dozing while driving and 0.5% reported totally unpredictable SOS episodes while driving. Risk factors for EDS were male gender, reduced activity of daily living, and a high daily levodopa equivalent dosage. Risk factors for SOS episodes while driving were an ESS score ≥10, male gender, and low Hoehn and Yahr staging. EDS is common in ambulatory patients with PD and is a major risk factor for dozing and for SOS episodes behind the wheel in patients who drive. © 2007 Movement Disorder Society  相似文献   
28.
Localized pleural plaques and lung cancer.   总被引:1,自引:0,他引:1  
In a mass chest radiography survey conducted in 1971 for 7,986 residents of three Finnish communities, 604 subjects (7.6%) with pleural plaques but not other asbestos-related radiographic signs were identified. The same number of referents, each individually matched to each plaque carrier on sex, birth year, and community, was selected from among persons in the same source population with no pleural plaques. The two groups were followed for investigation of incidence of lung cancer during 1972-1989. Twenty-eight of those with plaques and 25 referents contracted lung cancer (crude conditional RR = 1.1; CL95 = 0.7, 1.9). The application of the proportional hazards model, with adjustment for sex, age, and residence, resulted in a hazard ratio of 1.1 (CL = 0.6, 1.8). The risk ratio estimate may be biased; hence, the result is inconclusive in regard to the predictive assessment of lung cancer risk among carriers of pleural plaques.  相似文献   
29.
A significant minority of medical and dental students fail their undergraduate courses. Early warning systems (EWSs) have been developed in some areas of higher education to predict 'at-risk' students at an early remedial stage. An attempt is made to develop an EWS to predict failure in the bacteriology component of the Batchelor of Dental Surgery course at Manchester Dental School. A system based on class tests and previous end-of-year performance is derived which is used to predict those students likely to fail or fall in the bottom 20-25% in their finals examination. The predictors are combined by a simple equal weights method, which is found to have the same predictive power as using multiple regression. Failure was correctly predicted in 60% of cases, at the expense of 71% false alarms. The high number of false alarms reflects the low failure rate rather than the lack of predictive information. The need for effective cross-validation of EWSs is discussed; many previous studies have not been tested on independent data.  相似文献   
30.
Experimental studies demonstrated a severe cardiac load of the CO2 pneumoperitoneum caused by an accelerated after- and a decreased preload. Patients displaying cardiovascular risks are therefore often rejected from laparoscopic surgery. Hence, the pathophysiological changes and the intraoperative risk of the CO2 pneumoperitoneum in high-risk cardiopulmonary patients (NYHA II–III, n= 15) undergoing laparoscopic cholecystectomy are described. The changes in cardiac after- and preload seem to be due to the elevated intraabdominal pressure rather than transperitoneally resorbed CO2 and are reversible by desufflation. In one patient conversion to open operation had to be performed because of a severe drop in cardiac output and right ventricle ejection fraction. Mixed oxygen saturation was predicting intraoperative worsening in this case. The described pathophysiological changes may seem to be well tolerated even in high-risk cardiac patients. Monitoring of hemodynamics should include an arterial catheter line and blood gas analyses. Pharmacologic interventions or pressureless laparoscopic procedures might not be necessary as long as laparoscopic cholecystectomy is performed. Received: 13 December 1996/Accepted: 8 January 1997  相似文献   
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