Ambulatory monitoring of ultraviolet erythema in photosensitive subjects

Little is known about whether patients with photosensitive disorders exhibit a different ultraviolet erythema time course from subjects with a normal response to sunlight. We have described the application of an instrument for ambulatory monitoring of the development of ultraviolet erythema by a reflectance method in a group of patients with chronic actinic dermatitis (CAD) and in a group of normal subjects. Investigations of the time course have been reported previously but the techniques used relied upon manual measurement. Consequently sampling frequencies have been considerably lower than the one-minute sample rate used here. We have not demonstrated any difference in the rate at which erythema develops and peaks between patients with CAD and subjects with a normal response to sunlight.     

跟腱反射时间测定评价甲状腺功能的探讨

对103名甲状腺功能正常者,89例甲状腺功能亢进症(甲亢)患者,10例甲状腺机能减退症(甲低)患者,分别测定了跟腱反射时间并与放免测定血清T_3、T_4相比较。结果:甲状腺功能正常者符合率为100％,甲亢符合率为83％,甲低符合率为90％。认为,跟腱反射时间测定对甲状腺功能的判断比较淮确,并且方法简便易行。     

修正正交分段线性函数及其在线性与时变线性系统中应用

把分段线性函数和斜波脉冲函数进行统一处理，定义成新的函数，使得新的函数既保持了原先两种函数的基本特性，又获得微分和积分递推算法。应用中具有方便，快速计算的优点。     

Fluid shear induced endothelial cell detachment from glass - influence of adhesion time and shear stress

In this study, human umbilical vein and human saphenous vein endothelial cells were seeded on glass and exposed to fluid shear in a parallel-plate flow chamber. Cell retention, morphology and migration were studied as a function of shear stress and of adhesion time prior to exposure to shear. Three-hour and 24-h adhesion times gave rise to comparable cell retention values after 2 h of flow for both cell types. Cell retention decreased from 85 to 20% as shear stress increased from 88 to 264 dynes cm⁻² (8.8 to 26 Pa). Mean spreading areas decreased after the onset of flow, but subsequently stabilized to plateau values, which were smaller at higher shear stresses. Shape factors increased faster to higher values as cells were exposed to higher shear stresses, without any obvious preference in orientation of the cells with respect to the direction of flow. Migration was unidirectional with flow and linear with time. Migration was faster for cells which had adhered for 24 h than for cells which had adhered for 3 h and was accompanied by the presence of fibrillar structures left behind on the surface upstream of migrating cells. It is concluded that after 3 h adhesion to glass, cells have adhered with an adhesion strength that does not substantially increase during the next 21 h. However, during this time changes in cell-substratum interactions seem to occur judging by the differences in, e.g., migration rates.     

豚鼠内耳前庭感觉毛细胞的分离

用机械分离法从豚鼠前庭感觉上皮中分离出不同种类的前庭感觉毛细胞（ＶＨＣ）。ＶＨＣ主要可分为Ⅰ型和Ⅱ型细胞。两种细胞形态虽有所差异，但一般均有四形或瓶形胞体，胞核位于细胞基部，胞颈和纤毛变化较大。细胞的活性可通过１％中性红染色鉴定，发现在室温下，１ｈ内大约９０％以上的分离ＶＨＣ可维持其正常形态和活性。并参照对外毛细胞形态的研究提出活性ＶＨＣ的鉴别标准。此项工作为进一步研究ＶＨＣ的感觉机制和某些疾病的发生机理打下了基础。     

首次自杀未遂者和重复自杀未遂者的对照研究

目的探讨首次自杀未遂者和重复自杀未遂者的区别.方法检查126名因自杀未遂而入院的患者,分为首次自杀未遂组和重复自杀未遂组,获得有关的临床资料并进行自杀意图及自杀企图冲动性和致死性的测定,将有关项目作对比分析.结果有51(40.5%)名重复自杀未遂者,与首次自杀未遂者比较,重复自杀未遂者已婚居多、文化程度较低、缺乏固定的经济收入、有较多的既往精神科治疗史、常饮酒、企图自杀前与他人交流少,自杀意图较低,冲动性较高(P均＜0.05).结论对伴有某些危险因素的自杀未遂者应积极进行医学干预,以期减少自杀行为的再次发生.     

Effect of ethanol on sustained attention in rats

 Acute exposure to ethanol produces deficits in sustained attention in humans, but these attentional deficits have not been modeled in animals. In this study, an operant task was used to investigate the effects of low and moderate doses of ethanol on sustained attention in rats. Performance on a two-choice reaction time task over a 1-h session was assessed immediately following administration of ethanol (0.0, 0.5, 0.75, 1.0 and 1.5 g/kg IP). Each rat was required to respond to a light stimulus of variable duration (20, 100, and 500 ms) occurring at one of two locations. Under control and saline conditions, increases in stimulus length systematically increased choice accuracy and decreased reaction time. Ethanol produced a dose-dependent decrease in choice accuracy that interacted with time, with an initial impairment that was stimulus length-dependent followed by a general vigilance decrement. The data demonstrate that ethanol impaired the ability of rats to direct and sustain attention to brief, infrequent stimuli, and provide a model for further investigations into the underlying neurobiological mechanisms for ethanol-induced attentional deficits. Received: 19 March 1996 / Final version: 30 August 1996     

Cancellous Bone Structure in the Growing and Aging Lumbar Spine in a Historic Nubian Population

There is abundant data on cancellous bone in the aging human spine, but little relating to the growing vertebral cancellous bone in childhood and adolescence. The purpose of this study was to map vertebral cancellous bone in a growth and age series of historic skeletal samples and to make comparisons with data published on recent material. Lumbar vertebral bodies were collected from 65 skeletons (0–60 years) from a medieval Nubian population. Ethnohistoric information was collected to interpret conditions that might have influenced bone structure and metabolism. The cancellous bone was studied three dimensionally, using stereophotography and scanning electron microscopy and morphometrically by performing a semiautomatic structural analysis on digitized backscattered electron images of polymethacrylate-embedded material. The cancellous bone structure in the children consisted mainly of a densely packed, uniform network of small rodlike trabeculae. The greatest bone volume fraction with small, more platelike trabeculae was observed during adolescence. In young adults, larger platelike trabeculae were present in the central zone and smaller trabeculae in the superior and inferior zones, as described for modern skeletal material. Structural changes associated with aging were observed much sooner than in modern man. By the estimated age of approximately 50–60 years, the predominant architectural elements were slender rarified rods in both sexes. The ethnohistorical data suggest that this was essentially a black African population of physically active peasants, not likely to suffer Vitamin D insufficiency or deficient calcium intake. Thus an earlier onset of the biological age changes in cancellous bone found in modern populations was probably prevalent. Received: 1 March 1996 / Accepted: 31 December 1996     

1977～1990年同济医科大学新生视力状况分析

用统计学方法对14年来（1977～1990年）我校6746名新生（13492只眼）的视力状况进行分析。结果表明；新生正常视力逐年减少，视力不良率相应上升（P＜0.001）。城市学生的视力比农村学生差，男生的视力优于女生（P＜0.001）。17～19岁组的视力明显低于其他年龄组（P＜0.001）。高考分数线升高与正常视力者减少呈明显负相关；而与视力不良者增加呈正相关（P＜0.001,＜0.05）。本文认为近距离用眼持续时间过长及环境视域小等是引起视力不良的主要原因。