肿瘤转移抑制基因KISS-1蛋白、基质金属蛋白酶-2和血管内皮生长因子在结肠癌组织中的表达及临床意义

目的 检测结肠癌组织中肿瘤转移抑制基因KISS-1蛋白(KISS-1)、基质金属蛋白酶-2(MMP-2)和血管内皮生长因子(VEGF)的表达,分析其与结肠癌病理特征的相关性。方法 收集2009年1月至2010年6月在潍坊市人民医院60例行结肠癌切除术患者的癌组织标本作为观察组,60例良性结肠疾病手术患者的切除组织作为对照组。采用免疫组织化学法检测KISS-1、MMP-2和VEGF的表达。结果 观察组KISS-1、MMP-2和VEGF阳性表达率分别为31.7%、58.3%和78.3%,对照组分别为73.3%、16.7%和33.3%;观察组KISS-1阳性表达率明显低于对照组,差异有统计学意义(χ²=23.489,P<0.001);观察组MMP-2和VEGF的阳性表达率明显高于对照组,差异有统计学意义(χ²=27.469,P<0.001; χ²=25.817,P<0.001)。KISS-1、MMP-2和VEGF的表达与结肠癌组织学分型和TNM分期均有明显关系,差异有统计学意义(χ²=8.997,P=0.011; χ²=6.163,P=0.013; χ²=8.519,P=0.014; χ²=9.160,P=0.002; χ²=16.577,P<0.001; χ²=10.523,P=0.001)。结论 KISS-1、MMP-2和VEGF检测有助于了解结肠癌分化程度和临床分期,并为判断预后和个体化治疗提供参考依据。     

中国9省(区)1991——2009年6～17岁儿童青少年蔬菜水果摄人变化趋势 及其社会经济因素的影响

目的 分析1991-2009年中国9省(区)6～17岁儿童青少年蔬菜水果摄人的变化及其受社会经济因素的影响。方法 以1991-2009年“中国健康与营养调查(CHNS)”项目中12596名6～17岁儿童青少年为研究对象，应用SAS 9．2统计软件分析连续3天24小时膳食回顾调查及人口经济因素等数据。结果 调查人群蔬菜水果消费率均呈增加趋势。其中浅色蔬菜消费率从94．4％增加至96．9％(χ²=11．6，P＜0．0001)，深色蔬菜消费率从1991年的58．3％增加至82．4％(χ²=213．2，P＜0．01)，水果消费率从12．6％增加至45．4％(χ²=571．2，P＜0．0001)。蔬菜总摄入量中位数从1991年的250．0g/d下降至2009年的225．8 g／d(χ²=72．4，P＜0．0001)，其中浅色蔬菜下降36．6 g／d，深色蔬菜下降约40．0 g／d(χ²=92．8，P＜0．0001)，而水果摄入量增加50．0／d(χ²= 104．2，P＜0．01)。达到中国居民膳食指南蔬菜最低推荐摄人量(300g／d)的儿童比例从1991年的 38．9％下降至2009年的26．8％，而满足该指南水果推荐量(200g／d)的比例从2．0％增加到13．9％；2009年深色蔬菜摄入占蔬菜总摄入量一半以上儿童的比例约为25．1％。母亲受教育程度和家庭经济收入水平是影响水果消费的重要因素。结论 1991-2009年中国儿童青少年蔬菜水果消费率呈增加趋势，但深色和浅色蔬菜摄入量有所下降，存在明显摄入不足。建议采用有效的综合干预措施增加蔬菜和新鲜水果的摄人量，改善儿童营养状况。     

体重指数与谷氨酰半胱氨酸合成酶催化亚基基因多态性的交互作用对女性乳腺癌风险的影响

目的探讨谷氨酰半胱氨酸合成酶催化亚基(GCLC)rsl7883901多态性位点对BMI与乳腺癌关联的影响。方法于2008年10月至2010年6月对中山大学3所附属医院新诊断的839例乳腺癌患者(病例组)在接受治疗前及同时期863名年龄频数匹配的对照(对照组)进行问卷调查和收集血样；采用基质辅助激光解吸一飞行时间质谱仪(MALDI—TOF.MS)，在Sequenom平台检测rsl7883901位点基因型；采用非条件logistic回归分析计算BMI和GCLC与乳腺癌关联的OR值及其95%CI。结果(1)病例组和对照组接受调查时当前的BMI、20岁时的BMI和GCLCrsl7883901位点分布的差异均无统计学意义(P=0.44、0.52和0.47)；(2)未发现当前的BMI与绝经前及绝经后乳腺癌风险相关，20岁时BMI为18.5。22.9 kg/m²可降低绝经前乳腺癌风险(OR=0.69，95%CI：0.48~1.00)，而未发现其与绝经后乳腺癌风险相关；(3)在GCLC rsl7883901位点突变型CT/TT人群中，当前的BMI>/25 kg/m2显著增加乳腺癌风险(OR=1.91，95%CI：1.09～3.36)，而20岁时BMI为18.5～22.9 kg/m²与降低乳腺癌风险有关(OR=O.56，95%CI：0.31～o.99)。当前的BMI与GCLC基因多态性对乳腺癌发生风险存在交互作用(P=0.043)，而20岁时的BMI与GCLC交互项无统计学意义(P=0.15)。结论20岁时增加BMI可能是绝经前乳腺癌的保护因素；GCLC rsl7883901位点本身与乳腺癌发生风险无显著关联，但其变异基因型可使当前的肥胖状态(BMI≥25 kg/m2)显著增加乳腺癌发生风险。     

妊娠期妇女甲状腺功能减退对妊娠结局和胎儿影响的分析

目的 分析妊娠期妇女甲状腺功能减退(甲减)对妊娠结局和胎儿的影响。方法 选择2013年1月至2015年10月在上海市第八人民医院行产前检查并分娩的4286例孕妇为研究对象,入组患者均在孕10周时行甲状腺功能检查,分为甲减、亚临床甲状腺功能减退(亚甲减)和健康3组,分析甲减发生状况及其对妊娠结局和胎儿的影响。结果 共检出甲减209例,发生率为4.9%(209/4286),其中临床甲减85例,亚甲减124例。健康组早产发生率(1.0%)明显低于甲减组(10.6%)和亚甲减组(6.5%),差异有统计学意义(χ²=38.884,P<0.001;χ²=17.722,P<0.001);健康组贫血发生率(3.8%)明显低于甲减组(18.8%)和亚甲减组(9.7%),差异有统计学意义(χ²=30.949,P<0.001;χ²=23.275,P<0.001);健康组低体重发生率(1.1%)明显低于甲减组(14.1%)和亚甲减组(4.8%),差异有统计学意义(χ²=50.593,P<0.001;χ²=15.637,P<0.001);健康组胎儿窘迫发生率(1.9%)明显低于甲减组(10.6%)和亚甲减组(5.6%),差异有统计学意义(χ²=19.257,P<0.001;χ²=12.357,P<0.001);健康组胎儿Apgar评分(9.69±0.32)明显高于甲减组(9.25±0.45)和亚甲减组(9.28±0.44),差异有统计学意义(t=8.823,P<0.001;t=15.175,P<0.001)。结论 妊娠期妇女甲减可对妊娠结局和胎儿构成不利影响,临床应加强妊娠期妇女相关检查,早发现早治疗。     

北京市18~65岁慢性病患者吸烟状态、戒烟态度及危险因素分析

目的 了解北京市18~65岁高血压、糖尿病、血脂异常、COPD、哮喘患者的吸烟状态、戒烟态度及危险因素。方法 数据来源于2014年北京市成人慢性病与危险因素监测,即在北京市16个区/县采用多阶段分层整群抽样方法抽取180个社区共19 815名调查对象,以其中18~65岁人群作为研究对象。结果 18 405例有效样本中,男性高血压、血脂异常患者现在吸烟比例均高于非患者（分别χ²=17.695,P<0.001;χ²=39.292,P<0.001）;女性高血压、COPD、哮喘患者现在吸烟者比例均高于非患者（分别χ²=6.649,P=0.010;χ²=6.276,P=0.012;χ²=8.245,P=0.004）。吸烟者中,高血压患者1年内想戒烟比例低于非高血压患者（χ²=20.487,P<0.001）,COPD患者1年内想戒烟比例高于非COPD患者（χ²=6.085,P=0.048）。男性中糖尿病（χ²=9.219,P=0.010）、血脂异常（χ²=13.513,P=0.001）患者中已戒烟者控制情况好于现在吸烟者。多因素logistic回归结果显示,吸烟是高血压（OR=1.17）、血脂异常（OR=1.25）、COPD（OR=1.78）、哮喘（OR=1.57）的影响因素。结论 北京市18~65岁居民中部分慢性病患者现在吸烟比例高且戒烟意愿低;吸烟是高血压、血脂异常、COPD、哮喘的危险因素。     

河南省2014年手足口病重症病例病原学分析

目的 分析2014年河南省手足口病(HFMD)重症病例病原学特征。方法 整群抽取郑州市某儿童医院2014年4-6月244例HFMD住院病例作为研究对象,采集粪便标本,病原学检测采用荧光定量RT-PCR、病毒分离、VP1测序比对等方法。病原学特征统计分析采用SPSS 17.0软件。结果 244例手足口病病例中,重症组109例,轻症组135例,肠道病毒(EV)通用引物RT-PCR阳性229例,阳性率为93.85%。肠道病毒71型(EV71)、柯萨奇病毒A组16型(Cox A16)和Cox A10的感染构成比分别为83.84%、5.68%和8.30%。EV71感染致8例心肺功能衰竭,2例死亡;Cox A10感染致1例心肺功能衰竭、死亡。重症组与轻症组之间肠道病毒感染率差异有统计学意义(χ²=5.312,P=0.021)。采用Fisher精确概率法对重症组和轻症组EV71、Cox A16和其他EV感染构成比进行统计学比较,P=0.048。EV71和Cox A10感染致心肺功能衰竭发生率和致死率的差异无统计学意义(分别为χ²=0.051,P=0.821和χ²=2.198,P=0.138)。2014年河南省Cox A10分离株属于基因6型,VP1区段核苷酸和氨基酸同源性分别为94.3%~99.7%和96.3%~100.0%。结论 EV71仍然是河南省HFMD的主要病原。Cox A10在感染病原谱中所占比加大,且感染后可致心肺功能衰竭,应加强对其他EV的监测。     

877例髋部骨折患者发病情况及其流行病学特征分析

目的 分析髋部骨折患者发病情况及其流行病学分布特征。方法 调查杭州市2012年l一12月所有省市级医院收治的髋部骨折患者临床资料,统计分析髋部骨折患者的性别、年龄、骨折部位和骨折诱因等相关数据。结果 共纳入研究髋部骨折患者877例,其中男性516例(58.84%),女性361例(41.16%);年龄(62.1-4-11.2岁;髋部骨折患病率为10.0/10万,男性为11.2/10万,女性为8.8/10万,男性患病率明显高于女性,差异有统计学意义(x²=4.281,P=0.033)。髋部骨折患者数量居前3位的年龄段分别为71～82岁(344例,39.22%)、6l一70岁(196例,22.35%)和51～60岁(185例,占21.09%)。患者中股骨颈骨折显著多于股骨粗隆问骨折,差异有统计学意义(x²=21.423,P2=12.816,P2=13.773,P<0.001)。造成髋部骨折前3位的因素分别为跌倒、坠落和车祸,其构成比分别为64.88%、20.07%和10.49%。结论 年龄是发生髋部骨折的重要因素。老年人群髋部骨折以股骨颈骨折为主,多以跌倒引发。     

成釉细胞蛋白基因多态性与氟斑牙关系的研究

目的观察成釉细胞蛋白(AMBN)基因多态性在重庆市燃煤型氟中毒人群中的分布，探讨AMBN基因多态性与氟斑牙的关系。方法采用病例对照研究，在重庆市巫山、奉节县2个燃煤型氟中毒病区抽取8~12岁氟斑牙患病儿童100例、成人30例作为病例组;分别抽取非氟斑牙患病8~12岁儿童100例、成人30例作为内对照组，另在渝北区(非病区)抽取50名儿童、30名成人作为外对照组。采集所有研究对象外周静脉血，提取DNA，采用聚合酶链反应一限制性片段长度多态性(PCR-RFLP)方法测定3组人群AMBN基因7号外显子(538_{_} 540de1GGA),10号外显子(657A > G)和13号外显子(986C>T)位点基因型，观察并分析比较组间各基因型分布差异。结果病例及内、外对照组GGA/GGA基因频率分别为61.2%(74/121),78.5%(102/130)和74.3%(52/70 ), GGA/-基因频率分别为24.0% ( 29/121),15.4% ( 20/130)和22.9% (16/70 )，-/--(GGA完全缺失)基因频率分别为14.8%(18/121),6.1%(8/130)和2.8% ( 2/70 )，各组间的差异有统计学意义( x²=14.353, P=0.006 );病例及内、外对照组AA基因频率分别为86.8%(105/121),93.1%(121/130)和91.4% ( 64/70 ), AG基因频率分别为13.2%(16/121),6.9%(9/130)和8.6% ( 6/70 )，各组间差异无统计学意义(x²=2.972,P>0.05);病例及内、外对照组CC基因频率分别为81.0% ( 98/121),90.0% (117/130)和87.1%(61/70);CT基因频率分别为19.0% ( 23/121),10.0% (13/130)和12.9% ( 9/70)，各组间差异无统计学意义(x²=4.319,P>0.05)。与两对照组相比，病例组的GGA/GGA基因型频率降低(x²值分别为8.957,3.405,P值均<0.05 ), GGA完全缺失基因型频率增高(才值分别为5.134,6.833,P值均<0.05。单因素分析显示，携带一基因型的个体发生氟中毒的风险增高(病例组与内、外对照组比较，OR值分别为2.7, 5.9, P值均<0.05 )。与内对照组比较，病例组CT基因型频率增高(x²=4.139,P<0.05)。病区携带CT基因型的个体发生氟中毒的风险增高(OR=2.1,P< 0.05 )。结论AMBN基因7号外显子538_{_}540de1GGA和13号外显子986C>T位点多态性可能是影响氟斑牙发病的易感性因素之一。     

河南省2008－2013年男男性行为人群艾滋病流行趋势分析

目的 分析河南省MSM人群HIV感染流行趋势,为河南省艾滋病防治政策与策略制定提供科学依据。方法 分析2008-2013年艾滋病病例报告系统中同性性传播HIV/AIDS病例的变化趋势,利用MSM人群艾滋病综合防治专项调查数据分析该人群HIV感染率及危险行为变化。结果 2008-2013年河南省同性性传播病例构成从1.3%上升到17.1%,呈现快速增长趋势;专项调查数据显示,MSM人群HIV感染率呈现快速上升趋势,从2008年的4.69%增至2013年的8.33%(趋势χ²=39.24,P<0.001).单因素分析结果显示,年龄(χ²=21.03,P<0.001)、文化程度(χ²=31.66,P<0.001)、职业(χ²=14.59,P=0.01)、最近1次肛交行为安全套使用情况(χ²=134.97,P<0.001)、最近6个月同性性行为安全套使用情况(χ²=97.15,P<0.001)、最近1年性病症状(χ²=67.21,P<0.001)以及梅毒感染(χ²=163.60,P<0.001)均为感染HIV的影响因素。多因素分析结果显示,年龄、性病症状史、感染梅毒与艾滋病防治知识不知晓为感染HIV的危险因素。结论 河南省MSM人群中HIV感染呈不断上升趋势,男男同性性传播已经成为主要感染途径,该人群不安全性行为普遍存在,亟需采取有效措施控制HIV在该人群中的传播。     

静脉注射维生素C对脓毒症与脓毒性休克患者预后的影响: 随机对照试验的Meta分析

目的 评估静脉注射维生素C对脓毒症患者的疗效。 方法 计算机检索PubMed、Embase、Scopus、Cochrane Library和Clinical Trials数据库, 检索时限为建库至2022年12月。收集静脉注射维生素C治疗脓毒症或脓毒性休克的随机对照试验(RCT)英文文献。由2名研究者独立筛选文献、提取资料并评价纳入研究的偏倚风险后, 采用RevMan 5.3软件和Stata 15.0软件进行Meta分析。 结果 共纳入16项RCT研究, 包括3 301例患者。主要结局方面, 维生素C治疗组患者28天病死率略低于对照组, 但差异无统计学意义[RR=0.86, 95%CI(0.72~1.03), P=0.10; I²=44%, P=0.10]。次要结局方面, 静脉注射维生素C可缩短血管活性药物使用时间[MD=-23.44, 95%CI(-30.53~-16.35), P＜0.01;I²=0, P=0.97], 但对患者90天病死率、重症监护病房(ICU)病死率、医院病死率、机械通气持续时间、72 h序贯器官衰竭估计评分差值(△SOFA)、ICU住院时间、总住院时间无明显影响(P＞0.05)。 结论 静脉注射维生素C可明显缩短血管活性药物使用时间, 但现有证据尚不足以支持静脉注射维生素C可改善脓毒症或脓毒性休克患者的预后。需要更多高质量、多中心的RCT研究提供更多关于维生素C治疗脓毒症或脓毒性休克疗效的实质性证据。     

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.     

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.     

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.     

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.