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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   
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 Pontine omnipause neurons (OPNs) have so far been considered as forming a homogeneous group of neurons whose tonic firing stops during the duration of saccades, when the head is immobilized. In cats, they pause for the total duration of gaze shifts, when the head is free to move. In the present study, carried out on alert cats with fixed heads, we present observations made during self-initiated saccades and during tracking of a moving target which show that the OPN population is not homogeneous. Of the 76 OPNs we identified, 39 were found to have characteristics similar to those of previously described neurons, ”saccade” (S-) OPNs: (1) the durations of their pauses were significantly correlated with the durations of saccades; (2) the discharge ceased shortly before saccade onset and resumed before saccade end; (3) visual responses to target motion were excitatory; and (4) during tracking, S-OPNs interrupted the discharge for the duration of saccades and resumed firing during perisaccadic ”drifts”. However, the characteristics of 37 neurons (”complex” (C-) OPNs) were different: (1) the pause duration was not correlated with the duration of self-initiated saccades; (2) time lead of pause onsets relative to saccades was, on average, longer than in the group of S-OPNs, and firing resumed after the saccade end; (3) visual target motion suppressed tonic discharges; and (4) during tracking, firing was interrupted for the total duration of gaze shifts, including not only saccades but also perisaccadic ”drifts”. We conclude that cat OPNs can be subdivided into two main groups. The first comprises neurons whose firing patterns are compatible with gating individual saccades (”saccade” OPNs). The second group consists of ”complex” OPNs whose firing characteristics are appropriate to gate total gaze displacements rather than individual saccades. The function of these neurons may be to disinhibit pontobulbar circuits participating in the generation of saccade sequences and associated perisaccadic drifts. Received: 20 January 1998 / Accepted: 22 October 1998  相似文献   
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提出基于自适应方向滤波方法来提取左心室轮廓。在噪声的干扰下,引入经平滑处理的方向滤波能够得到精确的边缘,所获得的边缘方向矢量能够在边缘跟踪时对边缘走向预测,同时对参数进行自适应地调整。通过尽量少的人机交互,算法能够自动提取出左心室的轮廓。实验证明该算法增加了边缘提取的精度和一致性,同时显著地降低了计算复杂度。  相似文献   
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目的 帮助男护生正常学习和成长,培养职业情感,顺利完成学业,按期毕业、就业.方法 采用以问题为基础的管理方式,通过导师制第一时间的干预、课外跟踪随访和辅导,及时发现问题,提前干预.结果 男护生的学习成绩和职业情感均有不同程度的提高.结论 导师课外跟踪随访辅导制有利于对男护生诸多问题及时干预,助其顺利完成学业.  相似文献   
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目的总结与探讨追踪管理法在护理人员职业安全针刺伤管理中的应用效果。方法成立追踪管理小组,由专职人员对护理职业安全管理中的不良事件针刺伤进行个案追踪和系统追踪,分析产生护理职业安全事件的原因,不断完善追踪管理制度,形成一套完整的防控体系,预防护理职业安全针刺伤不良事件的发生。结果追踪管理法实施后,2013年护理职业安全针刺伤不良事件的发生明显低于2012年(P<0.05)。结论追踪管理法能积极防范护理职业安全针刺伤不良事件的发生,降低其发生率,保障护士的职业安全。  相似文献   
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A large body of research has demonstrated that affective disorders are characterized by attentional biases for emotional stimuli. However, this research relies heavily on manual reaction time (RT) measures that cannot fully delineate the time course and components of attentional bias. Eye tracking technology, which allows relatively direct and continuous measurement of overt visual attention, may provide an important supplement to RT measures. This article reviews eye tracking research on anxiety and depression, evaluating the experimental paradigms and eye movement indicators used to study attentional biases. Also included is a meta-analysis of extant eye tracking research (33 experiments; N = 1579) on both anxiety and depression. Relative to controls, anxious individuals showed increased vigilance for threat during free viewing and visual search, and showed difficulty disengaging from threat in visual search tasks, but not during free viewing. In contrast, depressed individuals were not characterized by vigilance for threat during free viewing, but were characterized by reduced orienting to positive stimuli, as well as reduced maintenance of gaze on positive stimuli and increased maintenance of gaze on dysphoric stimuli. Implications of these findings for theoretical accounts of attentional bias in anxiety and depression are discussed, and avenues for future research using eye-tracking technology are outlined.  相似文献   
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We compared blood pressure (BP) values, measured at a five year interval, in 2 777 boys and girls aged 4-18 years. BP values were converted into height and sex adjusted standard deviation unit scores. Correlation coefficients were significant but low for systolic BP score: 0.19 in boys and 0.15 in girls, and were even lower for diastolic BP score. These correlations are weaker than those observed for overall BP values (boys: 0.33, girls: 0.23), weight (0.82, 0.75) and height (0.87, 0.80). The probability of remaining in a high percentile (> 95th) is low since only 14p. cent of boys and 8p. cent of girls whose first systolic BP value was greater than the 95th percentile were still in this range five years later. Probability was still weaker for diastolic BP. BP tracking exists but would appear to be weak to permit early detection of future hypertensives, and does not justify preventive measures other than advice on diet and way of life.  相似文献   
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