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111.
To investigate the incidence and correlates of bulimic behavior, 1268 high school females were surveyed. A 47-item questionnaire was used to identify a group of students that would meet the DSM-III criteria for a probable diagnosis of bulimia. Students were then compared across the four content areas of demographics; body perception and weight information; dieting, exercise and menstrual behavior; and frequency of bingeing and purging behavior. Results indicated that 4.9% of the students met rigorous criteria for the diagnosis of bulimia. Between-group comparisons indicated that body dissatisfaction, drive for thinness, and chronicity of dieting differentiated the two groups.This work was supported by Biomedical Research Grant #RR5476, the Sears Allstate Foundation, and the George and Tina Barr Foundation.Main interest is eating disorders.  相似文献   
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Intramyocardial small vessel abnormalities are not commonly recognized. The best known abnormality is fibromuscular dysplasia involving the sinoatrial or atrioventricular nodal arteries. Small vessel disease has been reported as an isolated cardiac anomaly in individuals with sudden death, and may also be associated with other cardiac conditions including hypertrophic cardiomyopathy and mitral valve prolapse. The nature of the association is unknown, and the mechanism causing sudden death is sometimes obscure. We describe pathological changes of the intramyocardial small vessels of three individuals with sudden death. Abnormalities involved small vessels at different levels. In all the cases, the abnormalities were thought to have caused or contributed to the individual's death. The possible mechanisms of this are discussed.  相似文献   
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The purpose of this highly speculative article is to assess a broad range of possible developments in Cuba over the next five to seven years that could directly and adversely affect U.S. interests. By definition, therefore, it does not provide equal treatment to more optimistic and, salubrious scenarios. A key assumption is that the Cuban economy will not sustain a strong rebound to high levels of growth. Specific observations about how security challenges might impact certain U.S. government activities are also included according to the article’s terms of reference. No attempt is made to assign numerical or other probabilities to the counterfactual cases discussed. Finally, the future time frame examined includes treatments of a continuation of Fidel Castro's regime as well as the emergence of one or more successor governments. Brian Latell has been teaching courses on Cuba and Latin America at, Georgetown University for the past twenty-one years. He has written and lectured on Cuba, Mexico, and U.S. Foreign Intelligence Issues. In 1998 he co-editedEye in the Sky: The Story of the Corona Spy Satellites, published by the Smithsonian Press. He served as National Intelligence Officer for Latin America at the National Intelligence Council between 1990–1994. From 1994–1998 he was Director of the Center for the Study of Intelligence at CIA and chaired the Editorial Board ofStudies In Intelligence. Last year he retired from government service, and was awarded the Distinguished Intelligence Medal.  相似文献   
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The present study investigated the effect on witness confidence and accuracy of confusing questions often used by attorneys in court. Participants viewed a videotaped film and were individually questioned about the incident 1 week later. Half the participants were asked questions using six categories of confusing questions (negatives, double negatives, leading, multiple questions, complex syntax, and complex vocabulary); the remaining half were asked for the same information using simply phrased equivalents. Confusing questions reduced participant-witnesses' accuracy and suppressed confidence–accuracy relationships compared with the condition where simplified alternatives were asked. Witness performance was impaired by the fact that mock-witnesses rarely asked for a confusing question to be explained or qualified their answers. This experiment demonstrates the importance of ensuring that lawyers ask witnesses simple, clear, questions.  相似文献   
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We studied the biomechanical behaviour of ring and strip specimens from along the length of 18 vertebral arteries taken from 16 subjects aged 28-90 years, in order to consider some of the factors which may play a role in vertebral artery rupture. The method was chosen to allow a comparison between circumferential distension (ring samples) and longitudinal extension, (strip samples). The samples were extended between the jaws of a tensile testing apparatus until the specimen broke and a number of biomechanical parameters were derived. These were the percentage extension to break, the tensile strength, Young's modulus and the peak load. There were a number of important findings. The vertebral artery was shown to be susceptible to longitudinal stretching with a number of strip samples breaking when extended by as little as 16-20%. The tensile strength and load at peak of the strip specimens were correspondingly lower than for the ring samples. Marked intersubject variations were shown for all these parameters and prominent changes in behaviour occurred along the vertebral artery. This study indicates that the artery may be susceptible to head and neck movements which cause the vessel to stretch, and intersubject variations in behaviour may be one important explanation for the marked differences in outcome which appear to exist in subjects who suffer broadly similar head and neck insults.  相似文献   
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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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