老年人多重慢病患病现状及生活自理能力调查

目的了解老年人多重慢病患病现状,分析老年人生活自理能力影响因素。方法采用多阶段随机抽样法,对山西省3 250名老年人进行问卷调查,根据日常生活能力评定量表评估老年人自理能力。采用χ~2检验、二元logistic回归对老年人生活自理能力的影响因素进行研究。结果调查对象的多重慢病患病率为30.3%,平均每人患有2.8种慢性病,常见模式为高血压、糖尿病、冠心病、风湿或类风湿性关节炎、听力障碍、眼病中的二元或三元组合。年龄(参照:60～69岁,≥80岁OR=1.897,95%CI:1.252～2.874)、现在是否从业(参照:是,否OR=3.576,95%CI:1.467～8.716)、月收入(参照:≥3 000元;无收入OR=2.267,95%CI:1.254～4.097;1 000元OR=2.194,95%CI:1.223～3.936;3 000元OR=1.990,95%CI:1.233～3.213)、社区内是否有社区卫生服务站(参照:是;否OR=2.258,95%CI:1.564～3.259;不知道OR=2.205,95%CI:1.441～3.374)是老年人生活自理能力的影响因素。结论老年人面临多病共存的严峻挑战,生活自理能力不容乐观,应根据患病模式和可能影响因素采取有效的健康管理措施以改善老年人健康状况。     

石河子垦区老年人生活自理能力及影响因素分析

目的了解石河子垦区老年人生活自理能力现状及影响因素。方法采用多阶段随机抽样的方法分别抽取市区和团场各7个社区的1 400名≥60岁常住老年人进行面对面问卷调查,数据采用描述性分析、χ~2检验和logistic回归等方法进行分析。结果垦区生活完全自理的老年人1 101人,占78. 8%,完全不能自理的有87人,占6. 2%,仅有39人无慢性病,占2. 8%,生活中遇到自己做不了的事情,75. 4%的老年人得到家人及亲戚的照顾,9. 5%的人表示从不求人或寻不到帮助。多因素logistic回归分析示:导致垦区老年人生活自理能力差的主要因素及OR值(95%CI)为高龄(OR=18. 38; 95%CI:10. 11,33. 44)、患慢性病(OR=16. 36; 95%CI:1. 93,139. 05)、非独居(OR=2. 6; 95%CI:1. 36,4. 99);有利于提高老年人生活自理能力的主要因素及OR值(95%CI)为文化程度高(OR=0. 43; 95%CI:0. 20,0. 94)、月收入高(OR=0. 14; 95%CI:0. 05,0. 40)、锻炼(OR=0. 14; 95%CI:0. 08,0. 23)。结论垦区老年人生活自理能力较好,独居、锻炼、文化程度高、月收入高是生活自理能力的保护因素,高龄、患慢性病是其危险因素。     

中国听力残疾老年人辅助器具使用现状及其影响因素分析

目的了解中国听力残疾老年人辅助器具使用现状及其影响因素,为中国听力残疾老年人的防治与康复提供参考依据。方法利用2006年第二次全国残疾人抽样调查数据中29 495名≥60岁单纯听力残疾老年人作为分析样本,通过描述性分析、多因素logistic回归等方法分析听力残疾老年人辅助器具使用现状及其影响因素。结果中国29 495名≥60岁单纯听力残疾老年人辅助器具的使用率为7.62%,高龄、男性、居住在城镇、有配偶、受教育程度为初中及以上、家庭收入水平较高、有残疾人证、重度及以上听力障碍、有生活自理、与人相处功能障碍的听力残疾老年人辅助器具的使用率更高。多因素非条件logistic回归分析结果显示,人口学、社会经济、听力残疾程度及功能障碍因素与听力残疾老年人辅助器具服务利用相关。其中,中高龄、居住在城镇、有配偶、受教育程度为小学或初中及以上、家庭户人均收入≥1 500元、有残疾人证的听力残疾老年人使用辅助器具的可能性较高。在听力水平和活动与参与功能方面,听力障碍严重程度越高、存在生活自理、与人相处和社会参与功能障碍的听力残疾老年人,使用辅助器具的可能性更高。结论中国听力残疾老年人辅助器具服务的利用率较低,人口学、社会经济环境、听力及功能健康水平与听力残疾老年人辅助器具服务利用密切相关。     

我国西部地区农村老年人生活自理能力现状及影响因素分析北大核心

目的调查我国西部地区农村老年人生活自理能力的现状及影响因素,为提高老年人日常生活活动能力与健康服务提供依据参考。方法采用多阶段随机整群抽样方法,对我国西部地区4省(直辖市)8个县的3579名65岁及以上农村老年人进行生活自理能力(activities of daily living,ADL)问卷调查,并通过多因素Logistic回归模型分析影响自理能力水平的因素。结果此次研究对象共3573人,可自理人数3381人(94.63%)、依赖人数192人(5.37%),其中轻度依赖、中度依赖、不能自理分别占44.27%、26.04%、29.69%。多因素Logistic回归分析显示,以65~74岁年龄段为参照,75~84岁年龄段OR值为2.705(95%CI:1.840-3.977),85岁~年龄段为3.337(95%CI:1.881~5.917);以家务为参照,牧民OR值为4.738(95%CI:2.306~9.736);以已婚为参照,分居或离婚OR值为9.553(95%CI:3.056~29.866);以不患慢性病为参照,患3种及以上慢性病OR值为3.778(95%CI:1.659~8.606);以无跌倒为参照,跌倒OR值为2.382(95%CI:1.514~3.747);以听力正常为参照,听力严重退化OR值为3.707(95%CI:2.087~6.585)是老年人生活不能自理的独立危险因素;居住方式为丧偶独居OR为0.363(95%CI:0.169~0.781)和参加锻炼OR为0.308(95%CI:0.209~0.456)是保护因素。结论我国西部地区农村老年人生活自理能力现状不容乐观、影响因素较多,要对生活能力有依赖程度的老人提供合理的健康服务,如康复护理指导、健康教育及配备合适的辅助设施等,以预防或延缓老年人失能的发展进程。     

中国农村老年人失能状况及影响因素分析

目的了解中国农村老年人失能状况并分析失能影响因素。方法以2013年CHARLS调查所获得的数据为基础,对中国≥60岁农村户籍老年人的失能状况进行分析,利用Katz指数量表评价农村老年人日常生活自理能力(ADL),判断其失能状况;应用logistic回归模型对失能影响因素进行多因素分析。结果本研究从CHARLS 2013数据库中选取≥60岁农村老年人样本,共7 629人,其中失能农村老年人668人,失能率为8.8%;洗澡的失能率最高5.8%,吃饭的失能率最低1.2%。多因素分析结果显示,≥80岁(OR=4.186,95%CI=3.364~5.210)、低经济收入(OR=2.689,95%CI=1.832~3.947)、患有≥3种慢性病(OR=2.301,95%CI=1.827~2.897)、睡眠状况较差(OR=1.727,95%CI=1.384~2.155)、心理健康状况较差(OR=2.511,95%CI=1.962~3.214)的农村老年人失能风险较高;每月饮酒超过1次对农村老年人失能具有保护作用(OR=0.530,95%CI=0.417~0.675)。结论中国农村老年人失能率较高,应针对高危人群开展防控措施。     

城市老年人生活满意度及影响因素的调查研究——以保定市为例

目的探讨影响城市老年人生活满意度的主要因素,为制定提高老年人生活满意度的措施提供依据。方法采用生活满意指数A量表和自行设计的调查问卷,对河北省保定市居民生活小区及养老机构中838名年龄≥60岁老年人进行调查。结果 70.8%的老年人对生活比较满意和很满意。多因素logistic回归分析显示,机构养老(OR=6.311,95%CI:4.235~9.405)、其他养老方式(OR=52.917,95%CI:15.305~182.965)、参加社会活动(OR=0.253,95%CI:0.172~0.373)、离异或丧偶(OR=3.006,95%CI:1.998~4.532)、未婚(OR=3.048,95%CI:1.260~7.370)、健康状况良好(OR=0.550,95%CI:0.370~0.818)是老年人生活满意度的影响因素。结论应根据城市老年人生活满意度的影响因素,采取有针对性的干预措施,提高老年人生活满意度。     

60岁及以上老年人群认知功能障碍及影响因素分析

目的了解≥60岁老年人群认知功能障碍的患病情况及影响因素。方法于2015年4—6月采用整群随机抽样方法,在义乌市抽取1 576名≥60岁老年人为调查对象,采用《浙江省重大公共卫生监测项目调查问卷》和简易精神状态检查量表进行问卷调查,采用Logistic回归模型分析认知功能障碍患病的影响因素。结果有效调查1 569人,其中男性707人,女性862人,平均(69.42±7.26)岁。患认知功能障碍121例,患病率为7.71%。多因素Logistic回归分析结果显示,高龄(OR70岁-=1.792,95%CI:1.135~2.830;OR80岁-=4.060,95%CI:2.487~6.628)、女性(OR=1.739,95%CI:1.135~2.664)和自评家庭经济条件困难(OR=2.339,95%CI:1.239~4.415)是≥60岁老年人患认知功能障碍的危险因素,而同住人数≥4人(OR=0.462,95%CI:0.246~0.867)和参加运动(OR=0.592,95%CI:0.356~0.983)是≥60岁老年人患认知功能障碍的保护因素。结论义乌市≥60岁老年人认知功能障碍患病率为7.71%,年龄、性别、家庭经济条件、同住人数和运动情况是认知功能障碍患病的影响因素。     

平湖市敬老院老年人健康状况和就诊情况调查

目的了解平湖市敬老院老年人健康状况和就诊情况,为提高敬老院老年人保健服务提供依据。方法选取平湖市10家敬老院175名老年人进行问卷调查,收集慢性病患病、近半年就诊及近1年住院信息;采用《日常生活能力评分量表》评价调查对象自理能力;采用多因素Logistic回归分析敬老院老年人就诊和住院治疗的影响因素。结果共发放问卷175份,回收有效问卷162份,问卷有效率为92.57%,敬老院老年人轻度自理障碍18人,占11.11%,明显自理障碍23人,占14.20%,慢性病患病108人,占66.67%,近1年意外伤害事故发生率11.11%,近半年内就诊比例为55.55%,近1年住院比例为47.53%。多因素Logistic回归分析结果显示,初中文化程度的老年人(OR=0.280,95%CI:0.091~0.858)较文盲就诊率低;五保供养老年人(OR=2.418,95%CI:1.161~5.036)较寄养老年人就诊率高;患有1种慢性病的老年人(OR=2.656,95%CI:1.247~5.659)较未患慢性病的老年人就诊率高;女性老年人(OR=0.457,95%CI:0.228~0.913)住院率较低;明显自理障碍的老年人(OR=0.330,95%CI:0.170~0.931)虽较自理功能正常老年人就诊率低,但轻度自理障碍(OR=2.86,95%CI:1.092~7.502)和明显自理障碍(OR=8.278,95%CI:1.753~39.085)的老年人住院率则明显较高。结论文化程度低、五保供养、患有慢性病的老年人就诊需求相对较大;存在自理功能障碍的老年人住院需求大;建议进一步合理配置卫生资源,以提高养老机构老年人健康水平。     

湖北省抽样点老年人跌倒风险状况及其影响因素研究

目的研究湖北省抽样点老年人群跌倒风险情况及其相关影响因素,为采取针对性的预防措施提供理论依据。方法于2018年1-12月采取多阶段分层整群随机抽样的方法,在湖北省抽取1个区和1个县作为研究点。将符合纳入标准的2970名年龄≥60岁老年人作为研究对象,以标准化问卷进行调查,并进行身体测量和跌倒风险评估。用SPSS22.0统计软件进行χ²检验,采用多因素logistic回归模型分析老年人跌倒风险的影响因素。结果2970名老年人中存在跌倒风险的人数为1703人(57.34%),1年内摔倒1、2和3次及以上的比例分别为5.42%,0.88%和0.40%。多因素logistic回归分析结果显示,女性(OR=1.681,95%CI:1.431~1.975),高龄(70~74岁OR=1.925,95%CI:1.338~2.669,75~79岁OR=2.698,95%CI:1.883~3.886,≥80岁OR=5.014,95%CI:3.327~7.556),无配偶(OR=1.305,95%CI:1.054~1.615),跌倒相关药物服药史(OR=1.440,95%CI:1.215~1.707),日常生活活动能力受损(OR=3.238,95%CI:2.104~4.984)及患有眼疾(OR=2.844,95%CI:1.711~4.729)的湖北省抽样点老年人群跌倒风险较高,居住在农村(OR=0.515,95%CI:0.429~0.620)、每天进行体育锻炼(OR=0.715,95%CI:0.555~0.921)的湖北省抽样点老年人群跌倒风险较低。结论湖北省抽样点老年人群跌倒风险较高,且呈现影响因素多样化,个体跌倒影响因素叠加等现象,应重点关注女性、高龄独居和日常生活活动能力受损的老年人,通过社会、家庭和个体3个维度的综合性干预措施来降低老年跌倒风险。     

溧阳市农村居民慢性阻塞性肺疾病患病率及危险因素研究

目的了解溧阳市≥40岁农村居民慢性阻塞性肺疾病(COPD)的患病率及危险因素。方法采用多阶段分层整群抽样方法,抽取溧阳市农村地区≥40岁常住居民,进行调查询问和肺功能检测与身体测量,并利用logistic回归模型分析其危险因素。结果≥40岁常住农村居民COPD患病率为11.87%,男性患病风险高于女性(OR=3.24,95%CI:1.12~9.37);60~69岁和≥70岁年龄组的患病风险高于40~49岁组(OR=4.87,95%CI:1.92~12.39;OR=13.92,95%CI:3.96~48.93);有哮喘家族史患病风险显著高于无哮喘家族史居民(OR=2.61,95%CI:1.25~5.44);有呼吸道症状患病风险显著高于无呼吸道症状居民(OR=2.76,95%CI:1.41~5.40);烟民患病风险显著高于不吸烟居民(OR=16.81,95%CI:2.60~108.96)。结论 COPD是多因素综合作用的结果,可采取有效的干预措施,控制其危险因素,减少COPD的发生。     

Cholera in Haiti and other Caribbean regions, 19th century

Medical journals and other sources do not show evidence that cholera occurred in Haiti before 2010, despite the devastating effect of this disease in the Caribbean region in the 19th century. Cholera occurred in Cuba in 1833-1834; in Jamaica, Cuba, Puerto Rico, St. Thomas, St. Lucia, St. Kitts, Nevis, Trinidad, the Bahamas, St. Vincent, Granada, Anguilla, St. John, Tortola, the Turks and Caicos, the Grenadines (Carriacou and Petite Martinique), and possibly Antigua in 1850-1856; and in Guadeloupe, Cuba, St. Thomas, the Dominican Republic, Dominica, Martinique, and Marie Galante in 1865-1872. Conditions associated with slavery and colonial military control were absent in independent Haiti. Clustered populations, regular influx of new persons, and close quarters of barracks living contributed to spread of cholera in other Caribbean locations. We provide historical accounts of the presence and spread of cholera epidemics in Caribbean islands.     

Clinical Update on Nursing Home Medicine: 2013

This is the seventh article in the series of Clinical Updates on Nursing Home Care. The topics covered are antiresorptive drugs, hip fracture, hypertension, orthostatic hypotension, depression, undernutrition, anorexia, cachexia, sarcopenia, exercise, pain, and behavioral and psychological symptoms of dementia.     

Heavy Metals in Aquatic Macrophytes from Two Small Rivers Polluted by Urban,Agricultural and Textile Industry Sewages SW Poland

This article presents the results from a study of the comparison of 2 lowland rivers: the Olobok and the Pilawa in southwest Poland polluted by urban, agricultural, and textile industry sewages. pH and concentrations of Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Ni, Pb, Zn, nitrate, nitrite, ammonia, phosphate, and sulfate were measured in water samples and concentrations of Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, N, Na, Ni, P, Pb, S, and Zn were measured in stream bottom sediments and in the aquatic macrophytes Elodea canadensis, Callitriche verna, Potamogeton crispus, Potamogeton natans, and Ceratophyllum demersum from the river Olobok and Elodea canadensis, Polygonum amphibium, Potamogeton crispus, and Veronica beccabunga from the river Pilawa. The matrix of concentrations of 16 elements in 27 plant samples of 7 species from 15 sampling sites of 2 rivers and concentrations of 15 elements and pH in water samples and 16 elements and pH in bottom sediment samples of these sites was submitted to numerical classification, which revealed that sampling sites from the rivers were differentiated by the value of factor 1 of principal component analysis (PCA), which was related to the pH of water, Ca, Cu, Mg, Mn, and Ni in water and Cd, Cr, Cu, Fe, K, Mg, Na, Ni, P, and S in bottom sediments. More polluted parts of both rivers were differentiated from less polluted parts by the value of factor 2 of PCA, which was related to Pb, Zn, and sulfates in water and Ca and Zn in bottom sediments. Macrophytes from the Olobok and Pilawa rivers were differentiated by the value of factor 1, which was related to Ca, Co, Cr, Cu, Fe, Mg, Ni, N, Na, Pb, and S. Groups of macrophytes of more and less polluted parts of both rivers differed by the value of factor 2, which was related to P, K, and Mn. Downstream of the sewage outputs in both rivers, a significantly increased level of pollution occurs with elements correlated with factor 1: Among others were Cu and Cr, typical for the textile industry along the river Pilawa, and among others were Mn and Ni, typical for the urban and agricultural activities in the river Olobok.     

Evidence-Based Recommendations for an Optimal Prenatal Supplement for Women in the U.S., Part Two: Minerals

The levels of many essential minerals decrease during pregnancy if un-supplemented, including calcium, iron, magnesium, selenium, zinc, and possibly chromium and iodine. Sub-optimal intake of minerals from preconception through pregnancy increases the risk of many pregnancy complications and infant health problems. In the U.S., dietary intake of minerals is often below the Recommended Dietary Allowance (RDA), especially for iodine and magnesium, and 28% of women develop iron deficiency anemia during their third trimester. The goal of this paper is to propose evidence-based recommendations for the optimal level of prenatal supplementation for each mineral for most women in the United States. Overall, the evidence suggests that optimal mineral supplementation can significantly reduce a wide range of pregnancy complications (including anemia, gestational hypertension, gestational diabetes, hyperthyroidism, miscarriage, and pre-eclampsia) and infant health problems (including anemia, asthma/wheeze, autism, cerebral palsy, hypothyroidism, intellectual disability, low birth weight, neural tube defects, preterm birth, rickets, and wheeze). An evaluation of 180 commercial prenatal supplements found that they varied widely in mineral content, often contained only a subset of essential minerals, and the levels were often below our recommendations. Therefore, there is a need to establish recommendations on the optimal level of mineral supplementation during pregnancy.     

Interdisciplinary health professional education: a historical review

A historical review was conducted to examine the advances made, nationally and internationally, in interdisciplinary health professional education since the mid-1960s. One hundred and nineteen articles were reviewed and divided by decade into the following subheadings: models, courses, communication/group process issues, and international perspectives. Twenty-seven articles, categorized as models, defined the conceptual field, described curriculum and program development, or provided a framework for evaluation.Thirty-two articles dealt with interdisciplinary courses, focusing on objectives, content areas, or innovative methods. Nine articles contributed contenton interdisciplinary communication and group process issues, from which guidelines were abstracted. Fifty-one articles contributed an international perspective, leading to the recognition that interdisciplinary health professional education, practice, and research is a global movement.This revised version was published online in October 2005 with corrections to the Cover Date.     

Workshop report: Nucleic acid delivery devices for HIV vaccines: Workshop proceedings,National Institute of Allergy and Infectious Diseases,Bethesda, Maryland,USA, May 21, 2015

On May 21st, 2015, the U.S. National Institute of Allergy and Infectious Diseases (NIAID) convened a workshop on delivery devices for nucleic acid (NA) as vaccines in order to review the landscape of past and future technologies for administering NA (e.g., DNA, RNA, etc.) as antigen into target tissues of animal models and humans. Its focus was on current and future applications for preventing and treating human immunodeficiency virus (HIV) infection and acquired immune deficiency syndrome (AIDS) disease, among other infectious-disease priorities. Meeting participants presented the results and experience of representative clinical trials of NA vaccines using a variety of alternative delivery devices, as well as a broader group of methods studied in animal models and at bench top, to improve upon the performance and/or avoid the drawbacks of conventional needle-syringe (N–S) delivery. The subjects described and discussed included (1) delivery targeted into oral, cutaneous/intradermal, nasal, upper and lower respiratory, and intramuscular tissues; (2) devices and techniques for jet injection, solid, hollow, and dissolving microneedles, patches for topical passive diffusion or iontophoresis, electroporation, thermal microporation, nasal sprayers, aerosol upper-respiratory and pulmonary inhalation, stratum-corneum ablation by ultrasound, chemicals, and mechanical abrasion, and kinetic/ballistic delivery; (3) antigens, adjuvants, and carriers such as DNA, messenger RNA, synthesized plasmids, chemokines, wet and dry aerosols, and pollen-grain and microparticle vectors; and (4) the clinical experience and humoral, cellular, and cytokine immune responses observed for many of these target tissues, technologies, constructs, and carriers. This report summarizes the presentations and discussions from the workshop (https://web.archive.org/web/20160228112310/https://www.blsmeetings.net/NucleicAcidDeliveryDevices/), which was webcast live in its entirety and archived online (http://videocast.nih.gov/summary.asp?live=16059).     

Special Considerations for Prophylaxis for and Treatment of Anthrax in Pregnant and Postpartum Women

In August 2012, the Centers for Disease Control and Prevention, in partnership with the Association of Maternal and Child Health Programs, convened a meeting of national subject matter experts to review key clinical elements of anthrax prevention and treatment for pregnant, postpartum, and lactating (P/PP/L) women. National experts in infectious disease, obstetrics, maternal fetal medicine, neonatology, pediatrics, and pharmacy attended the meeting, as did representatives from professional organizations and national, federal, state, and local agencies. The meeting addressed general principles of prevention and treatment for P/PP/L women, vaccines, antimicrobial prophylaxis and treatment, clinical considerations and critical care issues, antitoxin, delivery concerns, infection control measures, and communication. The purpose of this meeting summary is to provide updated clinical information to health care providers and public health professionals caring for P/PP/L women in the setting of a bioterrorist event involving anthrax.     

Dynamics of cholera outbreaks in Great Lakes region of Africa, 1978-2008

Cholera outbreaks have occurred in Burundi, Rwanda, Democratic Republic of Congo, Tanzania, Uganda, and Kenya almost every year since 1977-1978, when the disease emerged in these countries. We used a multiscale, geographic information system-based approach to assess the link between cholera outbreaks, climate, and environmental variables. We performed time-series analyses and field investigations in the main affected areas. Results showed that cholera greatly increased during El Nino warm events (abnormally warm El Ninos) but decreased or remained stable between these events. Most epidemics occurred in a few hotspots in lakeside areas, where the weekly incidence of cholera varied by season, rainfall, fluctuations of plankton, and fishing activities. During lull periods, persistence of cholera was explained by outbreak dynamics, which suggested a metapopulation pattern, and by endemic foci around the lakes. These links between cholera outbreaks, climate, and lake environments need additional, multidisciplinary study.     

妊娠期糖尿病与妊娠期高血压疾病病理机制的相关性

妊娠期糖尿病(GDM)为妊娠期特有疾病,易造成孕产妇难产、产褥期感染、酮症酸中毒,胎儿窘迫、胎儿畸形甚至胎死宫内等不良妊娠结局。妊娠期高血压疾病(HDP)包括妊娠期高血压、子痫前期(preeclampsia)、子痫,以及慢性高血压并发子痫前期和妊娠合并慢性高血压,临床表现为高血压、蛋白尿及水肿,严重影响孕妇体内各脏器功能,是孕产妇及围生儿死亡的主要原因。HDP中子痫前期,尤其是重度子痫前期,是造成新生儿不良妊娠结局的重要原因,通常需要及时剖宫产终止妊娠。近年国内外许多研究已经证实GDM和HDP在内皮功能紊乱、血脂异常、炎症因子、肾素-血管紧张素-醛固酮系统(RAAS)等多方面有相关性。现就两种疾病在上述相关性方面进行综述。     

Major and trace element compositions of the UICC standard asbestos samples

Major and trace element compositions for chrysotile (2 samples), amosite, crocidolite, and anthophyllite UICC standard asbestos samples have been determined using UV-visible spectrophotometry, atomic absorption spectometry, flame photometry, volumetric analysis, and gravimetric analysis for major elements and x-ray and optical spectrometry for trace elements. The trace element data are for Li, S, Cl, Sc, V, Cr, Co, Ni, Cu, Zn, Ga, Rb, Sr, Zr, Nb, Ba, La, Ce, Pb, and Th and distribution in the various mineral phases is discussed. Am. J. Ind. Med. 32:592–594, 1997. © 1997 Wiley-Liss, Inc.