槟榔加工业作业人员视觉疲劳影响的研究

目的了解槟榔加工业作业人员视觉疲劳情况。方法选择从事槟榔加工的56名作业人员,测定他们在工作前、工作中、工作结束时的明视持久度,运动反应时,并分析测试结果的变化率。结果观察组临床症状和体征阳性率显著高于对照组(P<0.05)。选籽、切籽与点卤作业工人明视持久度、视觉运动反应时显著高于对照组(P<0.05)。结论槟榔加工业对作业人员的视觉疲劳有一定的影响。     

荧光灯频闪对视觉调节机能的影响

目的 观察荧光灯频对视觉调节机能的影响。方法 使用专门仪器测量１６例受试对象在３种不同频闪的荧光灯（１型灯无频闪、２型灯闪烁６００００Ｈ２、３型灯闪烁频率１００ＨＺ）下阅读４ｈ及８ｈ后双眼调节近点、集合近点、明视持久度等指标的变化情况。结果除个别数值外,３种指标４ｈ的测定值与实验前比较,差异无显著性（Ｐ〉０．０５）２型灯及３型灯测定值与１型灯比较,差异无显著性（Ｐ〉０．０５）,２型灯及３型灯测定     

电视屏幕闪烁对人体视觉调节功能影响的研究

目的 了解电视屏幕闪烁对人体视觉功能的不同影响。方法 选择视力正常的60名大学生为研究对象,采用眼调节近点、集合近点、视觉反应时、明视持久度、闪光融合临界频率的测定,了解观看无闪烁电视与普通电视3h前后人体视觉功能的变化。结果 观看3h无闪烁电视,受试视觉调节功能下降、视觉疲劳程度加大、注视的持久力减弱比观看普通电视要小。结论 视屏闪烁会影响视觉调节功能,可导致视觉系统紧张而出现视疲劳。     

航空管制作业人员神经精神紧张影响的调查研究

对航空管制作业人员的神经精神紧张状况进行了调查。结果表明：作业人员工后主观疲劳感觉明显增；闪光融合频率和明视持久度降低；神经行为功能下降；尿中肾上腺素；去甲纱和１７－羟皮质醇含量升高，。以上提示航空管制作业紧张程度较高，长时间的精神紧张可使作业人员产生精神疲劳。     

某中草药提取物改善学生视疲劳的效果观察

目的　评价某中草药提取物改善学生视力疲劳的效果。方法　选择 16～ 17岁在校自愿受试学生10 2人 ,随机分为试验组和安慰剂对照组 ,试验组服用某中草药提取物制成的保健食品 ,按照产品说明书的要求食用 4 5天 ,以食用前后的眼部自觉症状总积分、远视力和明视持久度作为主要功效观察指标。结果　试验组的眼痛、眼胀、畏光、视力模糊、干涩等症状明显改善 ,试验组的眼部症状总积分与对照组及实验前后比较差异均有极显著性 (P<0 .0 1) ;试验组的明视持久度有明显提高 ,与对照组及实验前后比较差异均有极显著性(P<0 .0 1) ;试验组缓解视力疲劳的总有效率达 73.1% ,与对照组比较差异有极显著性 (P<0 .0 1)。结论　该中草药提取物制成的保健食品具有明显改善视疲劳的作用。     

客轮驾驶员神经精神紧张的调查研究

对４８名长江客轮驾驶员的神经精神紧张状况进行了调查。结果表明，驾驶员工后疲劳积分增加，闪光融合频率和明视持久度降低，神经行为功能下降，尿中儿茶酚胺和１７－羟皮质醇含量升高，以上提示驾驶作业紧张程度较高，持续紧张可使驾驶员产生精神疲劳，不利于行船安全。     

视觉近点测定修布和验布作业视疲劳的初步探讨

应用视觉近点测定评价纺织厂不同作业工人的视疲劳。检查了32名修布工人和38名验布工人。同一工厂的33名保育员作对照组。结果表明:视觉近点的测定指标比调查受试者主诉的眼视觉症状更为敏感。修布和验布组在工作后,作业者的视觉近点比上班前明显变远,但时照蛆工作前后无明显变化。三组视觉近点比较,发现修布和验布组视觉近点的变化。提示由修布和验布作业引起的视觉疲劳,可以通过测定视觉近点来进行评价。     

中药熏蒸对强直性脊椎炎止痛效果的观察及护理

目的：观察中药熏蒸对强直性脊椎炎疼痛的止痛效果及护理方法。方法：强直性脊椎炎患者68例，分为观察组34例、对照组34例。对照组在药物治疗的同时按风湿科常规护理，观察组在药物治疗的基础上辅以中药熏蒸疗法，用0～10级线性视觉模拟量表（VAS）及5点口述疼痛评分问卷（VRS-5）比较两组止痛效果。结果：观察组疼痛评分均低于对照组，两组比较，差异有显著性意义（P〈0．01）。结论：中药熏蒸对减轻强直性脊椎炎疼痛有增效作用。     

自然光液晶及普通液晶电视对视疲劳影响

目的比较观看自然光液晶电视与普通液晶电视前后视觉疲劳发生程度。方法研究对象为59名20岁左右视力正常的大学生,每名受试者分别观看2.5 h的自然光液晶电视和普通液晶电视,在2次观看电视前后均进行明视持久度、闪烁光临界频率、注意力集中时间、视觉反应时、明度差别阈限等与视疲劳相关指标测试以及主观症状问卷调查。结果自然光液晶电视组与普通液晶电视组观看前后,奇偶数反应时和明度差别阈限差值分别为-0.096,-0.046 s和0.280,2.840 lx,而闪烁光临界频率和明视持久度前后差值大于普通液晶电视组,但差异均无统计学意义(P0.05);观看自然光液晶电视后只有眼胀、眨眼频率增加(P0.05);而观看普通液晶电视后发生眼痛、眼胀、视物模糊、视力下降、眩晕等的频率增加(P0.05)。结论与普通液晶电视比较,观看自然光液晶电视有缓解视觉疲劳的趋势,但有待进一步研究。     

VDT视保护屏对操作者视功能影响的研究

目的　了解电脑显示终端（ＶＤＴ） 视保护屏是否能保护操作者的视功能。方法　对某卫生学校４０ 名１７ ～１８ 岁学生进行,现场研究,观察指标为明视持久度、视觉运动反应时、阅字数、错误率、脑力工作能力指数。结果　操作者明视持久度、反应时、阅字数、脑力工作能力指数四项指标在有屏组与无屏组间比较,无统计学意义（ Ｐ＞ ０．０５） 。错误率在有屏组与无屏组比较中,表现为操作后即刻无屏组高于有屏组（ Ｐ＜ ０．０１）。结论　ＶＤＴ 保护屏（金属丝网型）对操作者视功能未显示明显的保护作用     

Characteristics of work intensity and fatigue in proof-readers in the polygraphic industry]

A group of proof-readers showed the elective resistance to fatigue from visual work by the end of working shift. Changed near point, decreased power and hardiness of the hand, aggravated self appraisal were more significant than altered achromatic visual stability, time of motor response to the light and critical flicker fusion frequency. The studied parameters were compared making use of Derevianko's index.     

精细作业女工视疲劳的研究

对某电子管厂从事精细作业的７２例女工与配对选取的７２例对照进行了视疲劳及有关因素的调查分析。结果表明：观察组有明显的视疲劳症状发生，四项视疲劳指与对照组比较也均有显著差异。对四项视疲劳指与各因素进行多元厢关及逐步回归分析发现，除工作物上易引起视疲劳外，近视力、辐辏近点、内隐斜、外隐斜等视功能不良也导致精细作业者视疲劳的主要因素。     

An experimental study of work load on VDT performance. Part 1. Effects of polarity of screen and color of display

Study were made on the effects of polarity of screen and color of display on work load of VDT tasks. The subjects of the present experiment were eight healthy male college students (age: 21-23 yr) having a naked binocular vision of not less than 0.7 and no astigmatism nor hyperopia. The test consisted of an experimental word processing task in which the subjects visually searched e's in given sequences of alphabetical letters displayed on the CRT and converted them to 5's through keyboard operation. As for experimental conditions, four levels of screen image, that is, positive and negative screens and green and white colored displays were adopted and 2 hr were given for each operation time. Critical flicker fusion (CFF), near point distance, accommodation time, subjective fatigue symptoms, heart rate, electromyogram in upper limbs and performance score were measured. The following results were obtained. Decrease in C.F.F. and extension of near point distance were observed in all experimental conditions during the operating time. Increase in complaints of subjective fatigue related to visual function was observed in all experimental conditions after two hour VDT task. Greater extension of near point distance and larger complaints of subjective fatigue were observed in subjects using the green colored display than in those using the white colored display. This suggests that the visual load using the green colored display is larger than that using the white colored display. A larger decreased in C.F.F. and greater complaints of subjective fatigue were demonstrated in subjects using negative screen than those using positive screen. This suggests that the visual load using the negative screen is larger than that using the positive screen.     

An experimental study of work load on VDT performance. Part 2. Effects of difference in input devices

Effects of the difference in input device on work load of VDT task were studied. The subjects of the experiment were eight healthy male college students (age: 21-22 yr) having a binocular vision of not less than 0.7 and no astigmatism or hyperopia. The test consisted of an experimental word processing task in which the subjects visually searched e's in given sequences of alphabetical letters displayed on the CRT and converted them to 5's through input device operation. As for experimental conditions, two kinds of input devices, namely, keyboard and lightpen were adopted and 1 h was provided as each operation time. Critical flicker fusion (CFF), near point distance, accommodation time, subjective fatigue symptoms, blinking counts, pupillary reflex, electromyogram in upper limb, neck and shoulder and performance score were measured. The results were as follows. Decrease in C.F.F. was observed in two experimental conditions during the process of operating time. Increments in complaints of subjective fatigue related to visual function were seen in the two experimental conditions after 1 h VDT task. A higher error rate in performance was observed in the subjects using the lightpen compared to the one using the keyboard. The frequency of both blinking and pupil-size changes were lower in the subjects using the lightpen compared to those using the keyboard. This suggests that the gaze time of the VDT screen with lightpen-condition is longer than that in keyboard-condition.(ABSTRACT TRUNCATED AT 250 WORDS)     

An experimental study on the duration of a single spell of work on VDT (visual display terminal) performance

The relation between work load and the duration of a single spell of work on VDT performance studied in an experimental word processing task. Nine healthy male college students performed 2-hour visual tasks under the following three sets of work conditions. In the first set, subjects performed VDT work for two hours without intermission. In the second set, subjects had a 10-minute intermission after a 1-hour task. In the third set, there was a 5-minute intermission after a 30-minute task. Critical flicker fusion, near point distance, subjective fatigue symptoms, heart rate, respiratory rate, blinking counts, electromyogram in upper limb and performance score were measured. Results are as follows. Decrease in critical flicker fusion, increase in near point distance and subjective fatigue symptoms appeared in all three sets of experimental conditions after two hour tasks. Increased slow wave components on electromyogram and increased errors in performance appeared after 60-minute or more tasks without intermission. Effects on the critical flicker fusion, near point distance, subjective fatigue symptoms, electromyogram, blinking counts and errors in performance were least in the third set. The results of this study suggest that in order to reduce operators' fatigue on VDT work of the conversation type, countermeasures such as shortening the duration of a single spell of work to less than 60 minutes and taking frequent short intermission are necessary.     

Influence of VDT (visual display terminals) work on eye accommodation

Visual display terminals (VDT) are popular in offices. Many VDT operators have complained about eye-function impairment. Experiments using an accommodo polyrecorder and an infrared optometer showed that visual tasks in VDT work might induce temporary effects in the visual accommodation system; prolonged the near point distance and the contraction time of accommodation and increased the low frequency component of the small fluctuation of accommodation after VDT work. The inhibition of accommodation caused by VDT work was more severe than that caused by the conventional hard-copy work, and changes in the accommodative function were found with statistical significance in the smaller-size character group but tended to deteriorate in the larger-size character group. The inhibition was more evident in the elderly and middle age groups than in the young age group. The inhibition of accommodation by VDT work might be inhibited by administration of methylcobalamin.     

Objective evaluation of visual fatigue in VDU workers

Prolonged work with visual display units (VDUs) may result ina wide range of subjective complaints of visual fatigue andsomatic disorders. Accepted tests for measuring the physiologicalcorrelates of eye discomfort are lacking. In this study, wetested accommodation and convergence, which are most often linkedexperimentally with VDU work. The tests were carried out on16 VDU and 13 control workers aged 24 to 43 years, before workat the beginning of the week (first examination) and again fourdays later at the end of the work day (second examination).The results in VDU workers showed that both accommodation andconvergence range significantly decreased. In addition, thoseworkers with powerful accommodative or convergence ranges atthe initial examination had a higher decrease. We suggest thataccommodation and convergence measurements can be used to evaluatevisual fatigue objectively in VDU workers.     

Temporary myopia and subjective symptoms in video display terminal operators

The study covered a group of female VDT operators assigned to data entry and data acquisition. Subjective VDT-related symptoms of asthenopia were assessed by means of a questionnaire. All operators were examined by an ophthalmologist. Visual acuity was measured using vision tables with optotypes. In order to achieve an objective assessment of VDT-induced visual fatigue, refractive power was measured at the beginning and at the end of the shift, using an infra-red autorefractometer. Changes in refractive power were then related to VDT work and asthenopia symptoms. Visual acuity defects were observed in 63.5% of the operators; in 36% of the cases the subjects were either unaware of the defects or the defects were not adequately corrected. 62.5% of the operators complained of subjective asthenopia symptoms. Asthenopia was not related to the number of hours at the VDT. The results suggest that ametropic subjects are likely to be more susceptible to visual fatigue than emmetropic subjects, since there was a tendency for the prevalence of asthenopia to increase in the former group. A significant decrease in refractive power (temporary myopization) was observed in 20% of the operators at the end of the shift at the VDT: all these subjects also complained of asthenopia, compared to 50% of the workers without end-of-shift myopization. The difference between the groups was highly significant (p less than 0.01); contrarywise, none of the subjects without asthenopia developed myopization. On the basis of these results, it can be concluded that end-of-shift myopization, as measured by an automatic refractometer, may be used as a reliable objective measurement of VDT-related visual fatigue.