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111.
石油存续企业的结构调整与优化,是当前石油企业深化改革的难点和重点问题。石油存续企业改革的核心应在明确定位的基础上,合理确定企业的主营业务与辅营业务,并以此为基础对现有的业务经营单位进行重组,最终对辅业经营单位进行结构调整和整合,实现企业的长期生存和发展。 相似文献
112.
李强 《北京工商大学学报(社会科学版)》2008,23(1):82-86
我国股指期货推出的法律环境面临诸多不确定因素,一方面,《证券法》、新《期货交易管理条例》、《关于审理期货纠纷案件若干问题的规定》、《刑法》和新《破产法》、《中国金融期货交易所交易规则》的颁布和修订,为强化市场监管提供了强有力的法律依据;另一方面,现有法律体系在交易所规则的效力、会计制度、税收制度、净额结算、交易所的性质、透支交易、交易信息的送达、期货公司的举证责任、涉外期货等方面规定不明确,应对相关法律进行修改、梳理和完善,并在刑法典中增加虚假陈述罪、非法经营期货业务罪、泄漏内幕信息罪和挪用期货保证金罪等内容。 相似文献
113.
In our zeal to deal with alcohol and drug abuse, we may have a distorted picture of what the majority of college students actually think about alcohol and drug use. Students in this study done at a public university located in the Deep South report being generally intolerant of substance abuse. 相似文献
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John D. Emerson David C. Hoaglin Frederick Mosteller 《Statistical Methods and Applications》1993,2(3):269-290
Summary Meta-analyses of sets of clinical trials often combine risk differences from several 2×2 tables according to a random-effects
model. The DerSimonian-Laird random-effects procedure, widely used for estimating the populaton mean risk difference, weights
the risk difference from each primary study inversely proportional to an estimate of its variance (the sum of the between-study
variance and the conditional within-study variance). Because those weights are not independent of the risk differences, however,
the procedure sometimes exhibits bias and unnatural behavior. The present paper proposes a modified weighting scheme that
uses the unconditional within-study variance to avoid this source of bias. The modified procedure has variance closer to that
available from weighting by ideal weights when such weights are known. We studied the modified procedure in extensive simulation
experiments using situations whose parameters resemble those of actual studies in medical research. For comparison we also
included two unbiased procedures, the unweighted mean and a sample-size-weighted mean; their relative variability depends
on the extent of heterogeneity among the primary studies. An example illustrates the application of the procedures to actual
data and the differences among the results.
This research was supported by Grant HS 05936 from the Agency for Health Care Policy and Research to Harvard University. 相似文献
116.
对普通野生稻和药用野生稻种子休眠的原因进行了探讨,表明野生稻种的遗传特性、形态性状、颖壳的透性和种子的生理特性与种子休眠有关。研究结果为打破野生稻种子休眠、提高其发茅力提供了依据和适宜的方法。 相似文献
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D R Lairson R Harrist D W Martin R Ramby T A Rustin J M Swint K Harlow J Cobb 《Journal of drug education》1992,22(4):337-352
Primary care physicians are well situated to identify patients with substance abuse problems and motivate them to seek appropriate assistance, but active programs are the exception. A study in a community setting was undertaken to assess the CAGE (the first letters of key words in a series of four questions about drinking: cut down; annoyed; guilty; and eye-opener), instrument in the routine screening for alcohol problems in both new and established patients. The screening process identified subjects for a pilot evaluation of a motivational interview designed to encourage problem-solving behavior. This article focuses on the screening results and the use of the CAGE instrument. During June and July of 1990, 687 patients of two primary care physicians belonging to a large group practice were asked to complete a health questionnaire that included the CAGE. Those who responded affirmatively to at least two of the four CAGE questions were requested to participate in follow-up assessment of problems associated with alcohol and health. The type and severity of alcohol problems experienced by patients who scored positive on the CAGE are described. Prevalence of a positive score on the CAGE was 8.6 percent with males, smokers, and blue collar and unemployed persons being more likely to score positive. The positive predictive value was .68. Primarily, persons with moderate alcohol problems were identified. Results show that the CAGE instrument is a useful screening device for identifying those with mild to moderate substance abuse problems, increasing the opportunity for intervention prior to serious medical complications. The instrument is easily administered, and has demonstrated relatively high levels of sensitivity and specificity. When combined with assessment and motivational interviews, the CAGE shows promise in the secondary prevention of substance abuse and related health problems. 相似文献