UVA对人角质形成细胞的氧化损伤作用

①目的　探讨紫外线A(UVA)对人角质形成细胞氧化损伤的机制。②方法　用 5J/cm2 UVA照射角质形成细胞 ,酶生化法检测活性氧 (ROS)的含量及超氧化物歧化酶 (SOD)、谷胱甘肽过氧化物酶 (GSH PX)活性的变化 ,流式细胞仪测定紫外线对角质形成细胞凋亡的影响 ,原位杂交技术观察 p2 1mRNA的变化 ,并与非照射组比较。③结果　与对照组比较 ,UVA照射组ROS含量升高 (t =113.6 8,P <0 .0 0 1) ,SOD、GSH PX活性下降 (t =5 7.2 3、19.0 4 ,P <0 .0 0 1) ,细胞凋亡率升高 (t=5 3.2 8,P <0 .0 0 1) ,p2 1mRNA表达增强。④结论　UVA对人角质形成细胞的损伤与氧自由基生成增多及细胞抗氧化能力抑制有关     

The development and evaluation of Student Training, Education and Practice for Dietetics CD-ROM: a computer-assisted instruction programme for dietetic students

The Student Training, Education and Practice for Dietetics (STEP‐DIET) CD‐ROM was developed at the University of Surrey to prepare dietetic students for the practical dietetic training component of their Nutrition/Dietetics degree. This study aimed to evaluate student response to the programme and its effectiveness as a teaching tool, based on the evaluation framework of D.L. Kirkpatrick (Evaluating a Course, 2nd edn. London, Kogan Page). Quantitative and qualitative methodologies were employed, with 41 dietetic students, separated by year group, completing questionnaires and taking part in six focus groups, at the University of Surrey. Student attitudes towards the instruction method and the STEP‐DIET programme itself were investigated, in conjunction with their perceived learning achievements. Students rated the programme highly in terms of design and content, however, there was a reluctance to accept computer‐assisted instruction (CAI) as a sole teaching method. A number of learning achievements relevant to dietetic practice were reported including a perceived increase in ability to conduct a dietetic interview and an increased understanding of the management of Type 2 diabetes. In general students reacted positively to the STEP‐DIET programme and it was perceived by students to be effective in preparing them for the practical component of their dietetic training.     

TJS全数字脑电工作站在空军招飞体检中的应用研究

随着科学技术的不断进步,为了尽快适应新形势的发展,招飞体检中我们在脑电图(dectroencephalogram,EEG)检测方面使用了电子计算机技术,并对新仪器应用于脑功能检测工作的价值进行了相关的研究,现报告如下:     

心率及重建相位窗对多层螺旋CT冠状动脉造影图像质量的影响

目的 探讨心率及重建相位窗对多层螺旋CT冠状动脉造影图像质量的影响。方法 80例健康体检者行16层螺旋CT回顾性心电门控条件下冠状动脉造影。结果 每位患者的4条冠状动脉分支(左冠状动脉主干、左前降支、左回旋支、右冠状动脉)分别用于图像质量分析。心率≤60次／min者，有82．1％(46／56支)的图像可用于诊断；心率61～70次／min者，有63．4％(104／164支)的图像可用于诊断；心率71～80次/min者，有41．20h，(28／68支)的图像可用于诊断；心率80次／min以上者有31．2％(10／32支)的图像可用于诊断。左冠状动脉前降支在60％～70％的重建相位窗时图像质量最佳，左冠状动脉回旋支在50％～60％时最佳，右冠状动脉重建相位窗为50％～70％较满意。结论心率及重建相位窗对多层螺旋CT冠状动脉造影图像质量有重要影响作用。     

Anterior eye focusing of peripheral ultraviolet and visible radiation albedo

Concern about short- and long-term ultraviolet radiation (particularly UVB) damage to the eye has led to increased research in this area. Numerous studies have confirmed the pathogenic enhancing roles of reflected ultraviolet (UV) and visible radiation in our environment. There is concern that conventional sunglasses do not protect the eye adequately from reflected rays (albedo), especially on the lateral aspect, from behind and from below. Using eye models and computer ray tracing methods, the pathways of oblique rays incident at the temporal peripheral cornea have been plotted by Maloof, Ho and Coroneo.¹ These rays are refracted and focused and theoretically can result in up to 20 times the concentration of incident irradiance at the nasal anterior chamber angle and nasal equatorial cortex of the crystalline lens. The purpose of this study was to determine the limits of angular subtense of the incident peripheral light which is refracted in this manner in human subjects and to investigate the relation between corneal shape and certain ocular parameters to the limits. A statistically significant positive correlation was found between temporal entrance angle and anterior chamber depth (r = 0.70, P< 0.0006). The entrance angle ranged from 15 degrees to 30 degrees and was located 10 degrees to 45 degrees posterior to the coronal plane. Our results support Maloof and colleagues' predictions for the implication of focused peripheral UV and high intensity visible radiation in the pathogenesis of pterygium and cortical cataract and emphasise the need for lateral eye protection in conditions of high ultraviolet albedo.     

The influence of pentoxifylline on motility and viability of spermatozoa from normozoospermic semen samples

In order to evaluate the effects of pentoxifylline on sperm motility and longevity, a controlled in-vitro study was conducted on normozoospermic donor semen samples using the Cellsoft automated system for sperm motility analysis. After incubation and selection, pentoxifylline was found to improve the recovery of spermatozoa and to increase their velocity. In the subgroup of progressively motile spermatozoa, curvilinear velocity was also enhanced. It is concluded that pentoxifylline has an effect on the vigour, but not on the pattern, of sperm motion. Pentoxifylline did not improve the motility characteristics of senescent spermatozoa in normozoospermic sperm samples. Sperm survival, as shown by supra-vital staining, and motility longevity both decreased with time after pentoxifylline treatment.     

Man-Machine Interfaces in Computer Assisted Surgery

The clinical potential of computer assisted surgery (W) has been more and more widely acknowledged since CAS systems have been introduced into the operating room (OR) theater.

Especially the improvements in safety and accuracy are remarkable and strengthen the ties between surgeons and engineers. Tumor stereotaxis was introduced to neurological surgery in the early 1980s, and currently systems with and without robotic navigation are in use for specific medical indications. Recently, solutions for computer assisted orthopedic surgery were developed and applied to various anatomical regions. However, with the establishment of CAS in vivo, a new complex of problems, which was not present in the laboratory setup, was introduced: the man-machine interface.

Currently, the complexity of available CAS systems requires the presence of at least one system engineer (often called the “operator”) in the OR. As a consequence, there is no possibility for direct communication between the surgeon and the machine or software.

Most of the program steps involved in CAS and choices to be made intraoperatively have to be transferred to the software by means of communication of the surgeon with the operator. Particularly, the establishment of a relation between the virtual object (i.e., a medical image) and the surgical object (i.e., the patient), often denoted as “matching” or “skeletal registration” requires intensive interaction of the surgeon with the computer. A literature survey revealed that no CAS system in clinical use exists without a system engineer or a comparable person, and our clinical experience indicated that the matching process is a weak point in most systems. Because it appears to be contradictory to cost-reduction efforts in health care to have a highly paid specialist in the OR, this research evaluates strategies to facilitate the man-machine interface with the final goal of establishing a direct control of the system by the surgeon or the medical personnel traditionally present at surgery. Options to be investigated include 1) a CAS control panel (virtual keyboard) as an integrated component of the existing navigation system and 2) introduction of a commercial voice-recognition system. The implementation of these strategies into the existing CAS setup at the Department of Orthopaedic Surgery at the Inselspital (University of Bern) and clinical experience gained are reported     

日光对皮肤弹性的影响

目的观察日光和年龄对皮肤弹性的影响。方法问卷调查受试者（郊县组94例，市区组105例）的日光曝晒情况，并应用皮肤弹性测量仪测量外眦部、鼻唇沟及眶下皮肤弹性参数，包括：弹性，黏弹性，可扩展性和张力参数。比较不同年龄组间、市区与郊县组间各弹性参数间的差异。结果市区和郊县各弹性参数均与年龄有较好的相关性，随年龄增长，皮肤各弹性参数均下降。郊县组与市区组比较，弹性和黏弹性参数差异较小，而可扩展性和张力参数差异较大。结论弹性和黏弹性参数可能与内在老化有关，而可扩展性和张力参数可能与光老化有关。     

Embedding Medical Student Computer Tutorials into a Busy Emergency Department

Objectives
To explore medical students' use of computer tutorials embedded in a busy clinical setting; to demonstrate that such tutorials can increase knowledge gain over and above that attributable to the clinical rotation itself.
Methods
Six tutorials were installed on a computer placed in a central area in an emergency department. Each tutorial was made up of between 33 and 85 screens of information that include text, graphics, animations, and questions. They were designed to be brief (10 minutes), focused, interactive, and immediately relevant. The authors evaluated the intervention using quantitative research methods, including usage tracking, surveys of faculty and students, and a randomized pretest-posttest study.
Results
Over 46 weeks, 95 medical students used the tutorials 544 times, for an overall average of 1.7 times a day. The median time spent on completed tutorials was 11 minutes (average [SD], 14 [±12] minutes). Seventy-four students completed the randomized study. They completed 65% of the assigned tutorials, resulting in improved examination scores compared with the control (effect size, 0.39; 95% confidence interval = 0.15 to 0.62). Students were positively disposed to the tutorials, ranking them as "valuable." Fifty-four percent preferred the tutorials to small group teaching sessions with a preceptor. The faculty was also positive about the tutorials, although they did not appear to integrate the tutorials directly into their teaching.
Conclusions
Medical students on rotation in a busy clinical setting can and will use appropriately presented computer tutorials. The tutorials are effective in raising examination scores.     

测胎儿器官重量探讨其生长发育规律

根据1022例新鲜胎尸的不同受精龄与体重，十项重要器官（心、肝、脾、左右肺、左右肾、左右肾上腺、胸腺等）的重量进行测量，将所测得的原始数据输入到IBM-PC/XT微型计算机内进行数据处理。探讨胎儿生长发育的基本规律。结果：（1）建立了胎儿体重与胎龄之间的推算式；（2）建立了胎儿各重要器官重量与胎龄之间的推算式；（3）建立了胎儿体重每月平均增长量与胎龄之间的推算式；（4）按胎儿体重每月平均增长量，用有序聚类分析方法，将胎儿生长发育过程划分为三个阶段。