实验家兔莱姆病血液学研究

本实验复制了莱姆病实验家兔模型，对血液生化23项进行了动态观察。结果表明，血液中谷丙转氨酶、γ-谷氨酰转肽酶、乳酸脱氢酶、谷草转氨酶、β-羟丁酸脱氢酶、磷酸肌酸激酶、胆固醇、尿素氮随病情加重而升高。葡萄糖、尿酸、磷随病情加重而减低。     

Multivariate modelling of responses to conditional items: New possibilities for latent class analysis

Questionnaire data may contain missing values because certain questions do not apply to all respondents. For instance, questions addressing particular attributes of a symptom, such as frequency, triggers or seasonality, are only applicable to those who have experienced the symptom, while for those who have not, responses to these items will be missing. This missing information does not fall into the category ‘missing by design’, rather the features of interest do not exist and cannot be measured regardless of survey design. Analysis of responses to such conditional items is therefore typically restricted to the subpopulation in which they apply. This article is concerned with joint multivariate modelling of responses to both unconditional and conditional items without restricting the analysis to this subpopulation. Such an approach is of interest when the distributions of both types of responses are thought to be determined by common parameters affecting the whole population. By integrating the conditional item structure into the model, inference can be based both on unconditional data from the entire population and on conditional data from subjects for whom they exist. This approach opens new possibilities for multivariate analysis of such data. We apply this approach to latent class modelling and provide an example using data on respiratory symptoms (wheeze and cough) in children. Conditional data structures such as that considered here are common in medical research settings and, although our focus is on latent class models, the approach can be applied to other multivariate models. Copyright © 2009 John Wiley & Sons, Ltd.     

不同孕期阶段孕妇凝血四项及FDP和D-二聚体的变化及临床意义

目的:研究不同孕期阶段(早、中、晚)孕妇凝血四项、血浆纤维蛋白(原)降解产物[plasma fibrin/fibrinogen degradation products, FDP]、D-二聚体的变化及临床意义,为临床诊疗提供理论支持。方法:回顾性分析2021年1月至2021年12月200例孕妇就诊资料中的凝血四项,纤维蛋白原(fibrinogen, FIB)、凝血酶原时间(prothrombin time, PT)、凝血酶时间(thrombin time, TT)、活化部分凝血活酶时间(activated partial thromboplastin time, APTT)。并对FDP与D-二聚体的检测结果进行统计分析,比较孕早期、中期、晚期三个阶段凝血四项、FDP和D-二聚体水平的变化。结果:孕早期、孕中期与孕晚期PT水平比较,差异有统计学意义(P<0.05);孕早期、孕中期与孕晚期三个阶段的TT相比,差异无统计学意义(P>0.05);孕早期的APTT明显长于中期、晚期孕妇,差异有统计学意义(P<0.05);孕早期、中期、晚期孕妇,随着孕周的增加,FIB水平逐渐升高...     

人格测验正反向题目的时间效应

目的通过分析人格测验正反向题目的时间效应,探讨人格测验中题目陈述方式对测验效度及质量的影响,为测验编制及研究提供参考。方法1230名士兵完成计算机呈现的艾森克人格问卷,记录被试完成每个题目所需要的时间,将正反向题目平均用时进行对比分析。结果反向题目整体平均用时显著高于正向题目平均用时(P<0.01);得分的反向题目平均用时显著低于得分的正向题目(P<0.01);未得分的反向题目平均用时显著高于未得分的正向题目(P<0.01)。结论反向题目的引入可以减少人格测验的反应偏差,提高测验的效度,但也会在一定程度上影响被试作答的心理过程。因此在测验编制的过程中应平衡使用正反向题目,但反向题目的语言要尽量简洁明了,减少对被试作答的影响。     

Influence of perinatal malnutrition on adult physiological and behavioral reactivity in rats

A series of experiments examined the behavioral and pituitary-adrenal response to novelty of perinatally malnourished rats tested as adults after nutritional rehabilitation begun at weaning. Neither the behavioral measures of ambulation, rearing and defecation, nor the plasma corticosterone response to a brief exposure to an open field differentiated the previously malnourished subjects from controls. Similar to controls, previously malnourished subjects were also capable of displaying a graded corticoid elevation to environments increasingly different from the home cage. However, exploratory behavior, as measured by head-dip frequency and duration in the hole-board, was reduced in the previously malnourished rats. Although latency and amount of fluid consumed in a novel environment did not differ, previously malnourished rats were unable to use the cues associated with a consummatory behavior to modulate the pituitary-adrenal response to novelty. Thus, perinatal malnutrition does not influence either the behavioral or physiological activational response to novel stimulation but appears to alter the ability of the animal to use a consummatory behavior to modulate this response.     

Differential effects of two types of environmental novelty on activity and sleep in BALB/cJ and C57BL/6J mice

Change in the sleeping environment can produce significant alterations in sleep. To determine how these alterations may vary with the amount of change and the relative reactivity of the sleeper, we examined the influences of environmental novelty on sleep in two mouse strains that differ in behavioral anxiety. Mice [BALB/cJ (n=7) and C57BL/6J (n=8)] were implanted for recording EEG and activity via telemetry. Following baseline data collection, activity and sleep were examined over 46 h after routine cage change, after placing a simple novel object (PVC Tee) in the home cage, and after handling controls. Mice of both strains showed immediate increases in activity and decreases in rapid eye movement sleep (REM) and non-REM (NREM) after cage change and novel object. Within strain, changes in activity and sleep were greater after cage change than after novel object. Changes in activity and sleep time were significantly correlated in each strain. Compared to C57BL/6J mice, BALB/cJ mice exhibited greater and longer duration initial reductions in sleep time, and greater increases in EEG slow wave activity power after cage change and novel object, but these changes were not followed with subsequent increases in sleep time. In contrast, C57BL/6J mice showed significantly greater subsequent increases in sleep time following the initial reductions induced by both manipulations. The results suggest that initial decreases and subsequent increases in sleep time are related to putative differences in the intensity of environmental novelty (cage change>novel object) and to previously described strain differences in anxiety (BALB/cJ>C57BL/6J).     

Physiological and behavioral effects of prior aversive stimulation (preshock) in the rat

Physiological and behavioral measures were assessed in rats that had been previously exposed to unsignaled inescapable intense shock (preshock). Animals subjected to such prior aversive stimulation exhibited greater adrenocortical steroid response compared to nonpreshocked controls when subsequently tested in the open field. An increment in defecation was also observed, with ambulation and rearing behavior being markedly inhibited in the preshocked rat during these sessions.     

Effects of aging on the novelty P3 during attend and ignore oddball tasks

The effects of attention were assessed on novelty P3 amplitude and scalp distribution elicited by environmental sounds in young and elderly volunteers who participated in either actively attended or ignored oddball conditions. For the young, novelty P3 amplitude decreased with time on task during both attend and ignore sequences. Amplitude decrements were greatest at frontal sites during the attend condition, but at all sites during the ignore condition. A reliable amplitude decrement was not observed for the elderly in either the attend or ignore oddball series. The data suggest that attention differentially activates multiple generators that contribute to scalp-recorded novelty P3 activity. The lack of novelty P3 habituation seen in the elderly is consistent with changes in frontal lobe function as age increases.     

Noradrenaline and neophobia

Lesions of the ascending noradrenergic bundles using the selective neurotoxin 6-hydroxydopamine increased neophobia to a number of novel tastes in rats. These lesions also increased some, but not all, measures of neophobia in novel environments. The results are discussed with reference to a recent hypothesis which suggests that the noradrenergic projections of the locus coeruleus mediate some aspects of fear and anxiety. Contrary to the prediction of this hypothesis, the noradrenergic lesions significantly increased rather than decreased neophobia. While these results point to an involvement of ascending noradrenergic systems in fear, at present the nature of this involvement cannot be specified in detail.     

The dorsomedial frontal cortex of the macaca monkey: fixation and saccade-related activity

Summary The activity of 249 neurons in the dorsomedial frontal cortex was studied in two macaque monkeys. The animals were trained to release a bar when a visual stimulus changed color in order to receive reward. An acoustic cue signaled the start of a series of trials to the animal, which was then free to begin each trial at will. The monkeys tended to fixate the visual stimuli and to make saccades when the stimuli moved. The monkeys were neither rewarded for making proper eye movements nor punished for making extraneous ones. We found neurons whose discharge was related to various movements including those of the eye, neck, and arm. In this report, we describe the properties of neurons that showed activity related to visual fixation and saccadic eye movement. Fixation neurons discharged during active fixation with the eye in a given position in the orbit, but did not discharge when the eye occupied the same orbital positions during nonactive fixation. These neurons showed neither a classic nor a complex visual receptive field, nor a foveal receptive visual field. Electrical stimulation at the site of the fixation neurons often drove the eye to the orbital position associated with maximal activity of the cell. Several different kinds of neurons were found to discharge before saccades: 1) checking-saccade neurons, which discharged when the monkeys made self-generated saccades to extinguish LED's; 2) novelty-detection saccade neurons, which discharged before the first saccade made to a new visual target but whose activity waned with successive presentations of the same target. These results suggest that the dorsomedial frontal cortex is involved in attentive fixation. We hypothesize that the fixation neurons may be involved in codifying the saccade toward a target. We propose that their involvement in arm-eye-head motor-planning rests primarily in targeting the goal of the movement. The fact that saccaderelated neurons discharge when the saccades are self initiated, implies that this area of the cortex may share the control of voluntary saccades with the frontal eye fields and that the activation is involved in intentional motor processes.