新型生物指示剂在紫外线消毒方面的应用

用一种可穿透紫外线的可溶性菌膜作为生物指示剂,检查紫外线的消毒效果。当紫外线剂量为12000μw·s/cm²时可杀灭99.9%以上金黄色葡萄球菌;50000μw·s/cm²可杀灭99.9%以上枯草杆菌芽孢。并且证明杀菌效力不完全取决于紫外线强度的高低,而照射剂量的大小在消毒效果中起关键作用。应用时根据不同消毒对象,调节照射时间,计算所需照射剂量,即可达到保证消毒质量的目的。应用新型生物指示剂检查紫外线消毒效果除简化操作程序外,还可以提高细菌回收的准确度及试验的重复性。     

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     

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.     

A nuclear mutant of Chlamydomonas that exhibits increased sensitivity to UV irradiation,reduced recombination of nuclear genes,and altered transmission of chloroplast genes

Summary Meiotic progeny of Chlamydomonas reinhardtii normally receive chloroplast genomes only from the mt ⁺ parent. However, exceptional zygotes, which transmit the chloroplast genomes of both parents or, more rarely, only those of the mt ^- parent, arise at a low frequency. Mutations at the mt ⁺-linked mat-3 locus were found previously to elevate the transmission of chloroplast genomes from the mt-parent, resulting in a much higher than normal frequency of exceptional zygotes. In this paper we demonstrate that an ultraviolet-sensitive nuclear mutation mapping at the uvsE1 locus, which is unlinked to mating type, also promotes chloroplast genome transmission from the mt ^- parent. This mutant, which was previously shown to reduce recombination of nuclear genes in meiosis, acts synergistically which the mat3-3 mutation to produce an extremely high frequency of exceptional zygotes. Through the use of restriction fragment length polymorphisms existing in the chloroplast genomes of C. reinhardtii and the interfertile strain C. smithii, we show that chloroplast DNA fragments from the mt ^- parent normally begin to disappear shortly after zygote formation. However, this process appears to be blocked totally in the absence of wild-type uvsE1 and mat-3 gene products. Our findings are consistent with the hypothesis that both gene products contribute to the mechanism responsible for uniparental inheritance of the chloroplast genome from the mt ⁺ parent.     

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。     

紫外线照射充氧自血回输疗法治疗多形性红斑临床及甲皱微循环观察

采用紫外线充氧自血回输治疗多形性红斑的治疗组总有效率为１００％，对照组为４０％；甲皱微循环改善率治疗组为１００％，对照组为７５％，组间差异均有非常显著性（Ｐ＜０．０１）．观察证明，紫外线照射充氧自血回输疗法是治疗多形性红斑的一种好方法．     

近红外乳腺扫描对早期乳癌的诊断价值(附1500例病例分析)

近红外线乳腺扫描对诊断乳腺癌,特别对早期乳癌具有高度的敏感性和诊断特异性,根据1500例证实的分析,近红外线乳腺扫描诊断率T1—T2期为95％;T1期直径<1cm及TO期乳癌诊断率为85％。 作者首先提出近红外线乳腺扫描的所见15种分型,本文叙述了近红外线乳腺检查的诊断原则及其诊断价值。 由于近红外线乳腺扫描具有高敏感性而且是无损害的简易的检查方法,我们认为应作为乳腺的常规检查及普查时的首选检查方法。     

UVB对角质形成细胞产生细胞因子的影响

角质形成细胞可产生多种细胞因子，这些细胞因子除介导炎症和免疫反应外，还参与组织细胞的生长和分化。UVB照射影响了角质形成细胞合成、分泌细胞因子，并影响细胞因子对角质形成细胞的作用及细胞因子之间的相互作用。概述角质形成细胞产生各种细胞因子的生物学效应。     

MTT法和水溶性四氮唑(WST-1)法检测中波紫外线照射HaCaT细胞后活力的比较

目的:观察中波紫外线照射后HaCaT细胞活力的变化并探讨水溶性四氮唑(WST-1)法检测的适用性.方法:将HaCaT细胞分为对照组(假照射组)、300J/m2、600J/m2、900J/m2紫外线照射后24h组(每组6个样本).600J/m2紫外线照射后4h组、8h组、1 2h组、24h组、48h组、72h组(每组6个样本).血球计数板计算HaCaT细胞数量.四甲基偶氮唑盐(MTT)法和水溶性四氮唑(WST-1)法活性测定HaCaT细胞活性.结果:MTT法显示300J/m2、600J/m2、900J/m2紫外线照射HaCaT细胞24h后光密度(OD)值明显较0J/m2组低;WST-1法各组OD值明显比0J/m2组低.MTT法显示600J/m2紫外线照射HaCaT细胞8h、12h、24h、48h、72h后OD值明显比0J/m2组低.WST-1法显示600J/m2紫外线照射HaCaT细胞4h后OD值较0J/m2组低;600J/m2紫外线照射HaCaT细胞8h、12h、24h、48h、72h后OD值明显比0J/m2组低.WST-1法的OD值与细胞计数、MT法OD值呈正相关.结论:随着紫外线剂量的加大和照射后时间延长,HaCaT细胞数量减少,细胞的活力下降,WST-1代谢活性亦降低,呈时间和剂量依赖性.HaCaT细胞可对WST-1进行代谢,适用于该细胞增殖研究.