Visual system of a naturally microphthalmic mammal: The blind mole rat,Spalax ehrenbergi

Retinal projections and visual thalamo-cortical connections were studied in the subterranean mole rat, belonging to the superspecies Spalax ehrenbergi, by anterograde and retrograde tracing techniques. Quantitative image analysis was used to estimate the relative density and distribution of retinal input to different primary visual nuclei. The visual system of Spalax presents a mosaic of both regressive and progressive morphological features. Following intraocular injections of horseradish peroxidase conjugates, the retina was found to project bilaterally to all visual structures described as receiving retinal afferents in non-fossorial rodents. Structures involved in form analysis and visually guided behaviors are reduced in size by more than 90%, receive a sparse retinal innervation, and are cytoarchitecturally poorly differentiated. The dorsal lateral geniculate nucleus, as defined by cyto- and myelo-architecture, cytochrome oxidase, and acetylcholinesterase distribution as well as by afferent and efferent connections, consists of a narrow sheet 3–5 neurons thick, in the dorsal thalamus. Connections with visual cortex are topographically organized but multiple cortical injections result in widespread and overlapping distributions of geniculate neurons, thus indicating that the cortical map of visual space is imprecise. The superficial layers of the superior colliculus are collapsed to a single layer, and the diffuse ipsilateral distribution of retinal afferents also suggests a lack of precise retinotopic relations. In the pretectum, both the olivary pretectal nucleus and the nucleus of the optic tract could be identified as receiving ipsilateral and contralateral retinal projections. The ventral lateral geniculate nucleus is also bilaterally innervated, but distinct subdivisions of this nucleus or the intergeniculate leaflet could not be distinguished. The retina sends a sparse projection to the dorsal and lateral terminal nuclei of the accessory optic system. The medial terminal nucleus is not present. In contrast to the above, structures of the “non-image forming” visual pathway involved in photoperiodic perception are well developed in Spalax. The suprachiasmatic nucleus receives a bilateral projection from the retina and the absolute size, cytoarchitecture, density, and distribution of retinal afferents in Spalax are comparable with those of other rodents. A relatively hypertrophied retinal projection is observed in the bed nucleus of the stria terminalis. Other regions which receive sparse visual input include the lateral and anterior hypothalamic areas, the retrochiasmatic region, the sub-paraventricular zone, the paraventricular hypothalamic nucleus, the anteroventral and anterodorsal nuclei, the lateral habenula, the mediodorsal nucleus, and the basal telencephalon. These results indicate that the apparently global morphological regression of the visual system conceals a selective expansion of structures related to functions of photoperiodic perception and photo-neuroendocrine regulation. We suggest that the evolution of an atrophied eye and reduced visual system is an adaptively advantageous response to the unique subterranean environment. Factors favoring regression include mechanical aspects, metabolic constraints, and competition between sensory systems. The primary advantage of sensory atrophy is the metabolic economy gained by the reduction of visual structures which do not contribute significantly to the animal's fitness. © 1993 Wiley-Liss, Inc.     

学龄儿童行为问题危险因素配对研究

将２１４名经Ｒｕｔｔｅｒ儿童行为问卷调查评定为有行为问题的学龄儿童与２１４名对照儿童进行了配比分析，以探讨学龄儿童行为问题的危险因素。研究结果表明，父、母文化程度和父亲职业是影响学龄儿童行为问题的重要因素；多因素条件Ｌｏｇｉｓｔｉｃ逐步回归分析结果显示父母文化程度偏低是学龄儿童行为障碍的两项独立危险因素。文中对学龄儿童行为问题的预防和矫治进行了讨论。     

线性回归法建立吸收度线性组合法的工作方程

根据一组已知浓度混合液的吸光度，经一元线性回归建立组分的工作方程，比较了建立工作方程的不同方法，并测定了三组分复方制剂安痛定注射液。本法可使吸收度线性组合法用于较复杂混合体系的测定。     

基于贝叶斯多变量联合模型的体检人群脑卒中发病风险因素的纵向研究

背景 脑卒中是目前影响人类健康的主要公共卫生问题之一;健康体检纵向数据累积了大量的健康信息,由于缺失数据多、样本量小等诸多问题,导致其利用率低、重要信息未能得到充分挖掘,进而对常见慢性病的有效防控等工作带来一定困难。目的 基于贝叶斯多变量联合模型,探讨体检人群脑卒中发病风险因素,为慢性病风险因素分析提供新的方法。方法 本研究使用空军军医大学西京医院健康医学中心2008—2015年的体检资料。随访情况：以首次发生脑卒中为结局事件,发生结局事件立即停止随访;若未发生,到2015年体检信息收集完成后结束随访;体检间隔时间为1年。依据随访过程中是否发生脑卒中分为脑卒中组和非脑卒中组。纵向观察变量包括总胆固醇（TC）、三酰甘油（TG）、低密度脂蛋白胆固醇（LDL-C）、高密度脂蛋白胆固醇（HDL-C）、体质指数（BMI）和收缩压（SBP）。采用多因素Cox回归模型分析基线情况对脑卒中结局事件的影响;采用贝叶斯多变量联合模型,分析随访过程中TC、TG、LDL-C、HDL-C、BMI和SBP的纵向变化轨迹对脑卒中发病的影响。结果 本研究共纳入234例研究对象,1 581条纵向随访记录,平均随访时间为...     

川崎病患儿丙种球蛋白耐药列线图模型的构建与验证

目的 基于Lasso回归和列线图构建并验证川崎病患儿对丙种球蛋白耐药的预测模型,以期为临床诊疗提供帮助。方法 回顾性收集2014年7月—2020年7月西南医科大学附属医院收治的474例川崎病患儿的临床资料,采用Lasso回归分析筛选重要的临床因素构建Nomogram模型,通过绘制受试者工作特征（ROC）曲线、Calibration校准曲线及DCA曲线验证模型的区分度、校准度及临床有效性。结果 共纳入474例患儿资料,其中339例作为训练集,135例作为验证集。Lasso回归分析显示,心脏表现、心外并发症、首剂静脉注射免疫球蛋白使用时间、中性粒细胞比例、红细胞分布宽度-标准差、血小板压积、白蛋白、系统性免疫-炎症指数及C反应蛋白/白蛋白是川崎病患儿丙种球蛋白耐药的预测因素。基于上述预测因素构建Nomogram模型,并分别在训练集与验证集人群中进行验证。训练集ROC曲线下面积（AUC）为0.784(95%CI:0.701,0.867),当最佳阈值取0.045时,相应的特异性和敏感性分别为0.490(95%CI:0.434,0.546)和0.935(95%CI:0.849,1.000);验证...     

重症监护病房重症脓毒症患者远期负性情绪发生率及相关因素分析

目的 探讨重症监护病房（ICU）重症脓毒症患者远期负性情绪发生率及相关因素。方法 选取2019年1月—2020年12月南阳市第一人民医院入住ICU的99例重症脓毒症患者作为研究对象,均随访2年。将并发焦虑抑郁的患者作为负性情绪组,未并发焦虑抑郁的患者作为非负性情绪组,分别有30和69例。分析两组患者年龄、性别、种族、体重、入院临床特征（住院时长、ICU时长及血清乳酸、降钙素、C反应蛋白水平）、入院诊断疾病（心血管系统、呼吸系统、传染病、其他）、疾病严重程度[急性生理学和慢性健康评估Ⅱ（APACHEⅡ）评分、脓毒症相关器官衰竭评估（SOFA）评分、感染性休克]、器官支持情况[机械通气、连续性肾脏替代疗法（CRRTn）]、入住ICU前72 h是否使用皮质类固醇及在ICU住院期间咪达唑仑、芬太尼、多巴酚丁胺、去甲肾上腺素和氟哌啶醇的累积剂量等基线特征。结果 两组患者性别构成、年龄、种族、体重、心血管系统疾病、呼吸系统疾病、传染病、其他疾病、APACHEⅡ评分、SOFA评分、机械通气、CRRTn、入住ICU前72 h使用皮质类固醇、咪达唑仑、多巴酚丁胺、去甲肾上腺素的累积剂量比较,差异均无统计...     

Neurophysiological and psychological predictors of genetic risk for schizophrenia

Mathematical genetic analyses were performed on a sample of schizophrenic families (25 probands and 58 first-degree relatives). Heritability coefficients were estimated for EEG power spectrum parameters and their topography, and also for psychological test data on thought and speech process disorder, designed to assess altered selectivity in cognitive activity. Multiple regression equations for genetic counseling regarding the prognosis of mental illness were derived from the neurophysiological and psychological measures.     

幕上高血压脑出血预后影响因素的多重线性回归分析

目的探讨影响幕上高血压脑出血（SICH）患者预后的相关因素,以指导临床治疗和评估预后。方法回顾性分析符合本研究纳入标准的幕上高血压脑出血324例完整病历。以一般资料、起病症状、入院查体、影像学资料、治疗方式、并发症等43项为自变量,以发病后1个月后功能独立性评定评分（functional independence measure,FIM）为因变量,建立多重线性回归模型,筛选出对预后有影响的因素,并比较各因素的影响大小。结果经统计学处理发现血肿体积、入院时收缩期血压、GCS评分、脑室是否积血、血肿体积扩大、是否并发肺部感染和应激性溃疡等7项对预后有显著性的影响。结论血肿体积、入院GCS评分和脑室是否积血对预后影响有重要意义,可作为SICH患者预后的关键性指标。     

Muscle synergies during shifts of the center of pressure by standing persons

Movements by a standing person are commonly associated with adjustments in the activity of postural muscles to cause a desired shift of the center of pressure (COP) and keep balance. We hypothesize that such COP shifts are controlled (stabilized) using a small set of central variables (muscle modes, M-modes), while each M-mode induces changes in the activity of a subgroup of postural muscles. The main purpose of this study has been to explore the possibility of identification of muscle synergies in a postural task using the framework of the uncontrolled manifold (UCM) hypothesis employing the following three steps in data analysis: (i) Identification of M-modes: Subjects were asked to release a load from extended arms through a pulley system, resulting in a COP shift forward prior to load release. Electromyographic (EMG) activity of eleven postural muscles on one side of the body was integrated over a 100 ms interval corresponding to the early stage of the COP shift, and subjected to a principal component (PC) analysis across multiple repetitions of each task. Three PCs were identified and associated with a push-back M-mode, a push-forward M-mode and a mixed M-mode. (ii) Calculation of the Jacobian of the system, which relates changes in the magnitude of M-modes to COP shifts using regression techniques: Subjects performed three different tasks (releasing different loads at the back, voluntarily shifting body weight forward and backward, at different speeds) to verify if the relationship between magnitudes of M-modes and COP shifts is task or direction specific. (iii) UCM analysis: Three tasks were chosen (load release in the front, arm movement forward and backward) which were associated with an early shift in COP. A manifold was identified in the M-mode space corresponding to a certain average (across trials) shift of the COP and variance per degree of freedom within the UCM (V_UCM) and orthogonal (V_ORT) to the UCM was computed. Across subjects, V_UCM was significantly higher than V_ORT when analysis at the third step was performed using a Jacobian computed based on a set of tasks associated with a COP shift in the same direction but not in the opposite direction. This result confirms our hypothesis that the M-modes work together as a synergy to stabilize a desired shift of the COP. Forward and backward COP shifts are associated with different synergies based on the same three M-modes.An erratum to this article can be found at     

职业紧张与冠心病的病例对照研究

目的 :(1)探讨男性列车乘务人员职业紧张与冠心病发病的关系。方法 :应用职业紧张因素测试量表 (OSI) ,对男性列车乘务人员中 3 9例冠心病患者进行 1:2的配比病例对照研究并进行多因素条件Logistic回归分析。结果 :(1)在控制和考虑了非职业紧张因素条件下 ,职业紧张与冠心病关系密切 (OR =2 18,95 %CI :1 15 -4 15 ) ,而且随着职业紧张程度的增加 ,患冠心病的危险性显著增加 ;(2 )以铁路乘务人员为对照时 (与病例同工种 ) ,职业紧张仍与冠心病发病有关联 (OR =4 43 ,95 %CI :1 60 -12 2 5 ) ,但其OR值明显低于以其他服务行业人员为对照时的OR值 (OR =9 75 ,95 %CI:3 18-2 9 92 )。结论 :职业紧张是引起男性列车乘务人员冠心病发病的重要危险因素之一。