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851.
The binding of charged substances from external aqueous media to hair has been investigated through the use of fluorescence microscopy. Eleven hair samples, reflecting various ethnic groups and cosmetic treatments, were tested. Rhodamine 6G, a cationic dye representative of drugs such as cocaine and opiates, showed incorporation throughout the hair of all samples except one. In contrast, fluorescein, an anionic dye representative of drugs such as THC carboxylic acid, was not readily incorporated. The incorporation of rhodamine 6G was faster for chemically 'straightened' and bleached African-American female hair than for untreated hair. Incorporation of rhodamine 6G followed a pH dependence, but an ionic strength dependence could not be established. These studies support three postulates: (1) electrostatic interactions explain the preferential binding of cationic drugs of abuse to hair; (2) the hair matrix, or the non-helical portion of hair, is accessible to external solutions and thus subject to contamination; and (3) cosmetic treatments may alter the helical portion of hair thereby increasing its accessibility to external contamination. 相似文献
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853.
Household survey data on age at first use of alcohol, tobacco, marijuana,and hard drugs can be biased due to sample selection and inaccuraterecall. One potential concern is attrition, whereby individuals who getinvolved with substance use at an early age become increasingly less likelyto be surveyed in successive years. A comparison of data from the NationalHousehold Survey on Drug Abuse (NHSDA) with data from a longitudinal studysuggested that attrition might have caused substantially less bias thandid forward telescoping, the inflating of age at first useover time. The evidence of forward telescoping was particularly pronouncedwith respect to age at first use of alcohol. This paper presents a procedurefor correcting the distribution of age at first use for forward telescoping(but not attrition) by viewing a portion of the NHSDA data collected insuccessive years as constituting a cohort study. Results are presented fromapplying this procedure with NHSDA data collected from 1982 to 1995 forrespondents born 1968–1973. The findings suggest that preventionprograms need to be introduced at an earlier age than would be indicatedby uncorrected retrospective data. Other implications are alsohighlighted. 相似文献
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856.
The HIV/AIDS epidemic continues to be a leading public health issue in the United States. During the past decade, the epidemic has shifted away from the gay community, although gay and bisexual men continue to be the largest single HIV exposure category. Now, HIV increasingly affects low-income people of colour in urban areas, as well as women. As AIDS becomes more and more a minority, inner-city disease, public focus on the epidemic as a significant social and political issue is waning. While a full survey of current issues in US law is beyond the scope of this article, the focus here is on current issues that are highly relevant to the direction the epidemic appears to be taking. 相似文献
857.
Trueman DL 《Journal of health law》2000,33(2):191-262
Managed care entities face numerous liability issues in today's changing healthcare environment. This Article provides the plaintiff with a comprehensive road map for navigating the many avenues of managed care liability. The author describes ERISA pre-emption provisions and suggests ways plaintiffs' attorneys can strive to narrow the pre-emption. The Article also provides in-depth analysis of each theory of managed care liability that has been litigated against managed care entities to date, and then goes on to explore state laws imposing liability on managed care entities, and how HMO liability is being reformed through legislative action. For plaintiffs' attorneys seeking the full spectrum of theories of managed care liability, or for defendants' attorneys wanting to remain updated on all potential claims to defend, this Article constitutes an extensive primer on the current issues. 相似文献
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859.
This Bibliography, covering items noticed between May and August1960, has been compiled wish the co-operation of Miss Ruth Jones(International African Institute) and Professor T. Heyse (latelyof the Belgian Ministry of Colonies). 相似文献
860.
This Bibliography, including items noticed between Februaryand May. 1958. has been compiled with the assistance of MissRuth Jones (International African Institute) and Professor T.Heyse (lately of the Belgian Minister of Colonies) 相似文献