甘肃省1997-2018年HIV/AIDS生存时间及影响因素分析

目的 了解1997-2018年甘肃省HIV/AIDS生存时间与影响因素。方法 利用国家艾滋病防治基本信息系统1997-2018年甘肃省疫情资料,采用回顾性队列研究方法,用寿命表法计算生存率,用Kaplan-Meier法绘制生存曲线并计算平均生存时间,用Cox比例风险回归模型分析HIV/AIDS的艾滋病相关死亡的影响因素。结果 6 813例HIV/AIDS中,715例（10.5%）死于艾滋病相关疾病,平均生存时间为195.9（95%CI：189.7~202.2）个月,12、60、120和180个月的累积生存率分别为91.5%、86.1%、79.9%和73.8%。Cox比例风险回归模型分析结果显示,在艾滋病相关死亡风险方面,诊断时的年龄≥ 51岁组是≤ 25岁组的1.906倍（95%CI：1.353~2.685）;其他传播途径病例是同性性传播病例的1.593倍（95%CI：1.226~2.069）;通过入院就诊、受血/血制品及术前检测发现的病例是通过出入境、婚/孕前检测及新兵体检发现病例的5.113倍（95%CI：2.083~12.547）;诊断时病程阶段为艾滋病的病例是HIV感染病例的4.012倍（95%CI：3.401~4.732）;未检测CD₄⁺T淋巴细胞（CD₄）的病例是首次CD₄值≥ 350个/μl病例的5.446倍（95%CI：3.835~7.732）;未接受抗病毒治疗的病例是已接受抗病毒治疗病例的12.019倍（95%CI：9.861~14.648）。结论 1997-2018年甘肃省HIV/AIDS平均生存时间超过16年。诊断时年龄≥ 51岁、通过入院就诊、受血/血制品及术前检测发现、诊断时病程阶段为艾滋病、未检测CD₄、未接受抗病毒治疗的HIV/AIDS死亡风险更高。应早发现、早诊断、早治疗,提高CD₄检测率及治疗率,延长HIV/AIDS的生存时间。     

北京市1995-2015年艾滋病病例诊断后生存时间与影响因素分析

目的 分析1995-2015年北京市HIV感染者/AIDS患者（HIV/AIDS）诊断后生存时间及影响因素。方法 运用回顾性队列研究方法,对1995-2015年中国艾滋病综合防治信息系统中报告的12 874例HIV/AIDS的数据资料进行分析,应用寿命表法计算生存率,采用Cox比例风险模型分析生存时间的相关因素。结果 12 874例HIV/AIDS中,303例（2.4%）死于艾滋病及相关疾病,接受抗病毒治疗9 346例（72.6%）。平均生存时间为226.5个月（95% CI：223.0~230.1）,1、5、10、15年生存率分别为98.2%、96.4%、93.2%、91.9%。Cox比例风险模型分析结果显示,艾滋病死亡风险较高的因素包括诊断时为艾滋病患者（比HIV感染者,HR=1.439,95% CI：1.041~1.989）;异性传播（比同性传播,HR=1.646,95% CI：1.184~2.289）;现有或曾有配偶（比未婚,HR=2.186,95% CI：1.510~3.164）;诊断时年龄≥ 60岁（比≤ 30岁,HR=6.608,95% CI：3.546~12.316）;诊断后首次CD₄⁺T淋巴细胞计数（CD₄）<350个/μl（比≥ 350个/μl,HR=8.711,95% CI：5.757~13.181）;未抗病毒治疗（比抗病毒治疗,HR=18.223,95% CI：13.317~24.937）。结论 1995-2015年北京市HIV/AIDS诊断后的平均生存时间为226.5个月。诊断为HIV感染、同性传播、未婚、≤ 30岁、首次CD₄ ≥ 350个/μl、接受抗病毒治疗的HIV/AIDS生存时间较长。相反,诊断为AIDS、异性传播、现有或曾有配偶、年龄≥ 60岁、CD₄<350个/μl、未抗病毒治疗的死亡风险较高。     

四川省1991-2017年HIV/AIDS生存分析

目的 分析1991-2017年四川省HIV/AIDS生存时间及其影响因素。方法 运用回顾性队列研究方法,对全国艾滋病综合防治数据信息系统中1991-2017年四川省新报告的143 988例HIV/AIDS的资料,采用寿命表法计算生存概率,用Cox比例风险模型分析生存时间的影响因素。结果 143 988例HIV/AIDS中,30 420例死于艾滋病及相关疾病（21.1%）,平均生存时间为11.51年（95% CI：11.39~11.64）;多因素Cox比例风险模型分析结果显示,HIV/AIDS生存的相关影响因素包括性别（男比女：HR=1.35,95% CI：1.32~1.40）、文化程度（小学及以下比初中及以上：HR=1.15,95% CI：1.12~1.18）、民族（汉族比其他：HR=1.46,95% CI：1.41~1.52）、职业（农民比其他：HR=1.26,95% CI：1.22~1.29）、诊断时年龄（≥ 55岁比15~24岁：HR=3.18,95% CI：3.02~3.36）、诊断时疾病状态（艾滋病比HIV感染：HR=1.44,95% CI：1.39~1.48）、抗病毒治疗（ART）（接受ART者比未接受ART者：HR=0.20,95% CI：0.19~0.20）、首次CD₄⁺T淋巴细胞计数（CD₄）（>500个/μl比<200个/μl：HR=0.42,95% CI：0.40~0.45）。结论 1991-2017年四川省HIV/AIDS诊断后平均生存时间为11.51年。男性、小学及以下文化程度、汉族、农民、诊断时较大年龄、诊断时为艾滋病状态是HIV/AIDS生存的危险因素,接受ART、首次CD₄水平高是HIV/AIDS生存的保护因素。     

山东省抗病毒治疗HIV/AIDS生存状况及影响因素分析

目的 了解山东省抗病毒治疗HIV/AIDS的生存状况及影响因素。方法 运用Kaplan-Meier（K-M）法及累积发生函数（CIF）估算2003-2015年山东省抗病毒治疗HIV/AIDS的艾滋病相关死亡发生率、部分分布比例风险回归模型（F-G模型）分析生存状况及影响因素。结果 竞争风险存在时,K-M法计算艾滋病相关死亡累积发生率高于CIF。CIF估算5 593例治疗HIV/AIDS随访1、3、5、10年艾滋病相关死亡累积发生率分别为3.08%、4.21%、5.37%和7.59%。大专及以上文化程度（HR=0.40,95% CI：0.24~0.65）HIV/AIDS的艾滋病相关死亡发生危险较低,现住址在鲁西地区（HR=1.33,95% CI：1.01~1.89）、医疗机构检测发现（HR=1.39,95% CI：1.06~1.80）、治疗基线方案含NVP（HR=1.36,95% CI：1.03~1.88）、治疗基线临床症状Ⅲ/Ⅳ期（HR=2.61,95% CI：1.94~3.53）、诊断1年后接受随访（HR=2.02,95% CI：1.30~3.15）、诊断基线CD₄⁺T淋巴细胞计数（CD₄）≤ 200个/μl（HR=3.41,95% CI：2.59~4.59）、治疗基线CD₄ ≤ 350个/μl（HR=5.48,95% CI：2.32~12.72）的HIV/AIDS发生艾滋病相关死亡风险高。结论 竞争风险存在时,K-M法高估艾滋病相关死亡累积发生率,优选竞争风险模型进行生存分析;早诊断、及时随访、早治疗可降低HIV/AIDS艾滋病相关死亡。     

贵州省1996－2015年注射吸毒人群HIV/AIDS死亡率及其影响因素分析

目的 了解贵州省注射吸毒人群中HIV/AIDS死亡情况及其影响因素,为降低HIV/AIDS死亡率提供参考依据。方法 采用回顾性队列研究方法,以我国艾滋病防治基本信息系统中1996－2015年贵州省注射吸毒人群HIV/AIDS为研究对象,应用Cox比例风险回归模型分析其死亡的影响因素。结果 共有3 958例注射吸毒HIV/AIDS纳入分析,全死因的死亡比例为44.01%（1 742/3 958）,总死亡率为7.80/100人年,生存时间M=8.08年;抗病毒治疗（ART）组死亡率为3.57/100人年,美沙酮维持治疗（MMT）组死亡率为4.08/100人年。多因素Cox回归分析结果显示,研究对象的死亡与性别、民族、确认HIV阳性时年龄、确认HIV阳性后首次CD₄⁺T淋巴细胞计数（CD₄）、ART和MMT有关;女性的死亡风险是男性的0.82倍（95% CI：0.69～0.98）;少数民族的死亡风险是汉族的1.39倍（95% CI：1.21～1.60）;确认HIV阳性时年龄≥50岁的死亡风险是<20岁的2.44倍（95% CI：1.07～5.56）;确认HIV阳性后首次CD₄≥500个/μl组的死亡风险是CD₄<200个/μl组的0.27倍（95% CI：0.22～0.32）;未参加ART的死亡风险是参加者的2.83倍（95% CI：2.45～3.26）;未参加MMT的死亡风险是参加者的1.35倍（95% CI：1.15～1.59）。结论 1996－2015年贵州省注射吸毒人群HIV/AIDS中,男性、确认HIV阳性时年龄较大者、确认HIV阳性后首次CD₄较低、未参加ART和MMT的病例,死亡风险较高。     

贵州省1995－2018年HIV/AIDS生存时间及其影响因素分析

目的 了解1995-2018年贵州省HIV/AIDS生存时间及影响因素。方法 采用回顾性队列研究的方法,从"艾滋病防治基本信息系统"中下载1995-2018年贵州省报告的所有现住址为贵州省的HIV/AIDS报告卡。进行统计分析,运用寿命表法计算生存率、Kaplan-Meier法计算生存时间、Cox比例风险模型分析HIV/AIDS生存时间的影响因素。结果 纳入研究对象HIV/AIDS 53 232例,死亡率为8.53/100人年(14 210/166 679.18);生存时间中位数为10.20(95%CI:9.91~10.48)年,第1、5、10、20年的累积生存概率分别为0.85、0.68、0.51、0.36、0.19;多因素Cox比例风险模型分析结果显示,男性(与女性相比,aHR=0.757,95%CI:0.727~0.788)、未接受过抗病毒治疗(与接受过抗病毒治疗相比,aHR=0.173,95%CI:0.165~0.181)、首次CD₄⁺T淋巴细胞(CD₄)<200个/μl(与首次CD₄ ≥ 200个/μl者相比,aHR=0.410,95%CI:0.387~0.435)、≥ 45岁 (与<45岁者相比,aHR=1.506,95%CI:1.193~1.901)、文盲(与高中及以上学历者相比,aHR=0.904,95%CI:0.832~0.982)、未婚(与离异或丧偶者相比, aHR=0.896,95%CI:0.848~0.946)、异性性传播(与同性性传播者相比,aHR=0.555,95%CI:0.487~0.632)、苗族等少数民族(与汉族相比,aHR=1.185,95%CI:1.114~1.262)、农民/民工(与家政/待业者相比, aHR=0.874,95%CI:0.834~0.916)均是影响病例生存时间的因素。结论 贵州省HIV/AIDS死亡率较高,近年来并未出现明显的下降趋势,男性、≥ 45岁、文化程度较低、少数民族、首次CD₄检测<200个/μl等是影响HIV/AIDS生存时间的因素。应该针对具有这些特征的病例加强治疗和随访管理,以提高其生存质量。     

广州市1991－2013年艾滋病相关死亡影响因素分析

目的 分析广州市艾滋病病毒感染者和艾滋病患者(HIV/AIDS)中艾滋病相关死亡的影响因素,为采取相应的措施提供依据。方法 利用国家艾滋病综合防治信息系统中1991－2013年广州市疫情资料,使用Cox风险比例模型分析艾滋病相关死亡的影响因素。结果 广州市HIV/AIDS病例中,报病时病程阶段为AIDS(HR=2.717,95%CI:2.039～3.621)、由医疗机构诊疗发现(HR=1.516,95%CI:1.159～1.981)、未接受过CD₄⁺T淋巴细胞检测(HR=4.866,95%CI:3.674～6.444)、符合治疗标准未治疗(HR=12.213,95%CI:8.467～17.616)、报病时年龄40岁以上的病例发生艾滋病相关死亡的风险更高。另外,不符合治疗标准而未治疗的病例发生艾滋病相关死亡的风险也高于接受抗病毒治疗的病例(HR=1.936,95%CI:1.145～3.272)。结论 及早发现HIV/AIDS病例,接受CD₄⁺T淋巴细胞检测和抗病毒治疗可降低HIV/AIDS的死亡风险,延长生存时间。     

沈阳市15~30岁学生HIV/AIDS患者抗病毒治疗相关因素分析

目的 探讨沈阳市学生HIV/AIDS患者抗病毒治疗（ART）的影响因素。方法 横断面调查获得2007-2015年沈阳市艾滋病治疗定点医院（中国医科大学附属第一医院）15~30岁学生HIV/AIDS患者ART相关信息,多因素logistic回归模型探讨ART的影响因素。结果 2007-2015年该医院共收治15~30岁学生HIV/AIDS患者146例,占累计治疗HIV/AIDS患者的6.1%（146/2 379）。患者均为男性,男男性行为传播途径占93.2%（136/146）,HIV延迟诊断率[诊断时CD₄⁺T淋巴细胞计数（CD₄）≤ 350个/μl]为52.7%（77/146）,患者中ART的构成比为67.1%（98/146）。多因素logistic回归分析显示,HIV诊断年份（aOR=1.21,95%CI：1.02~1.44）、年龄24~30岁（aOR=8.15,95%CI：1.46~45.52）和延迟诊断（aOR=2.22,95%CI：1.05~4.71）是学生HIV/AIDS患者ART的独立影响因素。结论 HIV诊断时间越晚、年龄越大及延迟诊断可能增加学生HIV/AIDS患者的ART比例。。     

湖北省荆州市1996-2021年HIV/AIDS病死率及其影响因素回顾性队列研究

目的 分析荆州市HIV/AIDS病死率及其影响因素。方法 资料来源于中国疾病预防控制信息系统的艾滋病综合防治信息系统,选取现住址为荆州市、确诊时年龄≥15岁、确诊时间为1996-2021年的HIV/AIDS作为研究对象。采用乘积极限法绘制死亡曲线,Cox比例风险回归模型识别死亡的影响因素。结果 HIV/AIDS共3 304例,随访16 091.5人年,死亡893例,病死率为5.5/100人年。HIV/AIDS确诊后1、5和10年的累积死亡概率分别为15.4%、25.0%和34.6%,参加抗病毒治疗者1、5和10年的累积死亡概率为6.9%、14.4%和23.7%,未参加抗病毒治疗者1、5和10年的累积死亡概率为68.0%、90.1%和98.7%。Cox比例风险回归模型分析结果显示,未参加抗病毒治疗者的死亡风险高于参加抗病毒治疗者（aHR=9.85,95%CI：8.19~11.85）;参加抗病毒治疗者死亡的危险因素包括男性（aHR=1.64,95%CI：1.29~2.08）、确诊时年龄≥60岁（aHR=3.52,95%CI：2.38~5.20）、注射吸毒/其他途径感染（aHR=2.38,95%CI：1.30~4.34）、医疗机构发现（aHR=1.53,95%CI：1.11~2.11）和首次CD4⁺T淋巴细胞（CD4）计数<50个/μl（aHR=2.58,95%CI：1.87~3.58）,死亡的保护因素是较高文化程度（高中/中专：aHR=0.64,95%CI：0.46~0.90;大专及以上：aHR=0.42,95%CI：0.24~0.73）。未参加抗病毒治疗者死亡的危险因素包括确诊时年龄较大（30~岁：aHR=2.32,95%CI：1.40~3.84;45~岁：aHR=2.61：95%CI：1.59~4.27;≥60岁：aHR=3.31,95%CI：2.01~5.47）、首次CD4计数较低（<50个/μl：aHR=10.47,95%CI：6.47~16.56;50~199个/μl：aHR=2.31,95%CI：1.08~4.94;200~349个/μl：aHR=2.35,95%CI：1.46~3.79）。结论 1996-2021年荆州市HIV/AIDS病死率较高,首次CD4计数、抗病毒治疗和确诊时年龄是影响HIV/AIDS死亡的主要因素,应进一步坚持扩大检测和“发现即治疗”政策,提升抗病毒治疗效果和HIV/AIDS生存率。     

宁波市2004-2015年抗病毒治疗HIV/AIDS患者生存分析

目的 了解2004-2015年宁波市接受抗病毒治疗的HIV/AIDS患者流行病学特征及生存情况。方法 采用回顾性队列研究方法,对研究对象的流行病学特征进行描述性分析,利用寿命表法计算生存率、Kaplan-Meier法绘制生存曲线、Cox比例风险回归模型分析影响死亡的危险因素。结果 2 347例研究对象中,接受抗病毒初始治疗的年龄中位数为35（IQR：27～45）岁,以男性、本地、已婚或同居、异性性传播、基线CD₄⁺T淋巴细胞计数（CD₄）≤200个/μl、WHO分期Ⅰ期为主。第1、5、7、10年的累计生存率分别为96.75%、92.36%、91.87%、90.02%。多因素Cox比例风险回归模型分析显示,年龄越大死亡危险度越高,接受抗病毒治疗的>60岁HIV/AIDS患者是≤20岁组的17.34倍（95% CI：2.11～142.71）;基线WHO临床分期Ⅳ期患者死亡危险是Ⅰ期的2.83倍（95% CI：1.67～4.80）;耐药患者死亡风险是不耐药患者死亡风险的3.26倍（95% CI：1.77～6.01）;相较于同性性传播途径,血液传播是患者死亡的危险因素;CD₄值越低,死亡风险越大;BMI<18.5 kg/m²、未婚是患者死亡的独立危险因素。结论 宁波市HIV/AIDS患者抗病毒治疗效果显著,生存率较高。关爱老年人群,针对流行病学特征加强宣传教育,扩大监测范围,早发现早诊断早治疗,提高抗病毒治疗者的依从性是降低病死率的有效措施。     

Calcium intake in the elderly: validation of a dietary questionnaire

Epidemiological studies of calcium and osteoporosis have been hampered by the lack of a suitable tool for assessing calcium intake. This report describes a new frequency and amount questionnaire for measuring present and past calcium intake in the elderly. The validity of the questionnaire was tested against two commonly used standards of dietary assessment, five-day duplicate diets and seven-day weighed dietary inventories. The resulting correlation coefficients were, respectively, r = 0.76 and r = 0.69, while that for repeatability was r = 0.84. Furthermore, the questionnaire categorized subjects into thirds of the distribution of intake with almost no gross misclassification. It is suggested that the present findings may be extended to the majority of normal, healthy elderly subjects, implying wide application for the questionnaire in the assessment of calcium intake in the elderly.     

The human drama of genetics: 'hard' and 'soft' media representations of inherited breast cancer

This paper examines media coverage of 'breast cancer genetics', and explores its implications for public understanding. We present a content analysis of coverage in British newspapers and look at a variety of popular forms, including women's magazines, television soap opera and radio drama. Genetic/inherited risk receives a great deal of coverage across a wide range of media formats and outlets. Much of this attention has focused on individuals from 'high risk families' and dilemmas around prophylactic mastectomies. Through examining media coverage, combined with interviews with media personnel and their sources, we show why this story proved so attractive to the media and highlight the different production values which influence coverage. Finally, we introduce preliminary findings from focus group discussions to demonstrate how such 'human interest' framing has engaged audience attention and influenced public understandings. The paper concludes by highlighting the implications for analysing, predicting, and engaging with, media representations of science.     

Worker education in the primary prevention of occupational dermatoses

This paper reports the evaluation of a skin care education programmeconducted on a fine chemicals manufacturing site where over1,000 employees are located. Approximately 60% are involvedin chemical manufacture. Over a 12 month period production staffreceived training in prevention of occupational dermatoses linkedto a site-wide poster initiative. The incidence of new casesof occupational dermatoses fell from 0.055 (70 cases in 1,277employees) to 0.021 (27 cases in 1,277 employees) before andafter the intervention respectively (p<0.0001). After otherfactors such as chemicals handled, observer bias and changesin reporting related to socioeconomic climate were taken intoaccount it is concluded that this study demonstrates the importanceof worker education as a tool for primary prevention of disease.Training materials such as video and poster presentations maybe effectively used in the chemical manufacturing industry asan adjunct to prevention and control of exposure to substanceshazardous to the skin. Such methods may also be used in otherindustries where there are significant risks of dermatoses.     

Regional Variation in Travel-related Illness acquired in Africa,March 1997–May 2011

To understand geographic variation in travel-related illness acquired in distinct African regions, we used the GeoSentinel Surveillance Network database to analyze records for 16,893 ill travelers returning from Africa over a 14-year period. Travelers to northern Africa most commonly reported gastrointestinal illnesses and dog bites. Febrile illnesses were more common in travelers returning from sub-Saharan countries. Eleven travelers died, 9 of malaria; these deaths occurred mainly among male business travelers to sub-Saharan Africa. The profile of illness varied substantially by region: malaria predominated in travelers returning from Central and Western Africa; schistosomiasis, strongyloidiasis, and dengue from Eastern and Western Africa; and loaisis from Central Africa. There were few reports of vaccine-preventable infections, HIV infection, and tuberculosis. Geographic profiling of illness acquired during travel to Africa guides targeted pretravel advice, expedites diagnosis in ill returning travelers, and may influence destination choices in tourism.     

深圳公立医院管理体制改革制度设计

深圳公立医院管理体制改革实行政事分开、管办分开,在理事会架构下按法定机构模式组建市医管中心,落实公立医院运营管理自主权.作者从当前公立医院管理体制的弊端入手,介绍了深圳市进行公立医院管理体制改革的基本思路及改革方案设计的主要举措,深入剖析了的改革方案的特点,并对改革效果进行了预测.     

Self-reported health problems among Swedish miners one year after unemployment

Unemployment is considered to be a public health concern sincedeterioration in the health of the unemployed is often anticipated.However, for some groups, such as miners, unemployment mightimprove health due to a cessation of potentially harmful occupationalexposures. This study evaluates the health of 79 miners in oneSwedish iron-ore mine, and 226 age-matched controls from thegeneral population, during one year after the closure of themine. The participants received a questionnaire regarding medicalhistory and subjective symptoms at the beginning of the studyperiod, and after one year. Statistically significant negativeeffects on self-reported health attributable to unemploymentwere not found, although neuropsychiatric symptoms were morecommon among the unemployed miners. The miners reported a statisticallysignificant improvement in grip force (p=0.031). They had asignificantly higher prevalence of symptoms associated withmining related exposures when compared with the population controls;pain in the upper extremities [relative risk (RR)=2.27, 95%confidence interval (Cl)=1.44–3.59), back pain (RR=1.84;Cl=1.237–2.75), vasospastic disease of the fingers (RR=2.05;Cl=1.18–3.57) and obstructive respiratory symptoms (attacksof dyspnea and wheezing: RR=3.67; Cl=1.167–11.6).     

Excès de cas humains et animaux de tularémie en France au cours de l’hiver 2007–2008 : émergence ou phénomène isolé ?

Context

Tularemia is a zoonosis affecting humans and hares in France. We describe the results of surveillance in both species, in 2007 and 2008.

Methods

Human tularemia cases are mandatorily notifiable in France since 2003. In hares, surveillance relies on volunteer hunter associations in all districts of the country. Data from mandatory reports and volunteer surveillance in 2007/2008 were analyzed and compared with previous results.

Results

In 2007/2008, 144 cases were reported in humans and 117 cases in hares. This was a 100% increase compared to previous years. Human cases differed from those of previous years only by the frequency of contact with breeding animals. Human cases without any documented risk exposure were also more frequent.

Conclusion

An increase of tularemia cases occurred in 2007/2008 in both species. Complementary studies are needed to identify the species reservoir in France to understand the causes of this peak of cases.     

The design of hazard risk assessment matrices for ranking occupational health risks and their application in mining and minerals processing

Two hazard risk assessment matrices for the ranking of occupational health risks are described. The qualitative matrix uses qualitative measures of probability and consequence to determine risk assessment codes for hazard-disease combinations. A walk-through survey of an underground metalliferous mine and concentrator is used to demonstrate how the qualitative matrix can be applied to determine priorities for the control of occupational health hazards. The semi-quantitative matrix uses attributable risk as a quantitative measure of probability and uses qualitative measures of consequence. A practical application of this matrix is the determination of occupational health priorities using existing epidemiological studies. Calculated attributable risks from epidemiological studies of hazard-disease combinations in mining and minerals processing are used as examples. These historic response data do not reflect the risks associated with current exposures. A method using current exposure data, known exposure-response relationships and the semi-quantitative matrix is proposed for more accurate and current risk rankings.     

Effects of nitrogen dioxide on red blood cells of rats: Changes in components of red cell membranes during in vivo exposure to NO2

Red cell membranes, prepared from red blood cells of rats exposed to 4, 10, or 20 ppm nitrogen dioxide (NO₂) for 1 to 10 days, were examined for evidence of changes in membrane components. Appreciable changes were not found in contents of phospholipid and cholesterol during exposure to 10 ppm NO₂. By contrast, protein content altered with the time of exposure. Moreover, changes in protein composition were observed by employing sodium dodecyl sulfate — polyacrylamide gel electrophoresis. Twenty-four-hour exposure to NO₂ at the concentration above 10 ppm resulted in a marked increase in the percentage of lysophosphatidylethanolamine (LysoPE) to the total phospholipids. The prolonged exposure to 10 ppm NO₂ gave rise to a further increase in LysoPE, whereas the percentage of phosphatidylethanolamine (PE) showed a gradual decrease. A 1-day exposure to 4.0 ppm NO₂ also caused an increase in sialic acid content and decreases in those of PE and hexose. In addition to contents of these components the percentage of LysoPE increased 5 days after exposure and the elevated values were maintained up to the end of exposure period. These results demonstrate that red blood cells in circulation exhibit different membrane properties in terms of lipid and carbohydrate composition during 10 days of exposure to 4.0 ppm NO₂.