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271.
Guidelines have existed in medicine for many centuries. Galen's doctrine of laudable pus sent many to an early grave, but variance in treatment put the practitioner in a difficult position, especially if all did not go well. Currently, guidelines proliferate, allegedly based upon careful evaluation of evidence culled from a variety of sources. However, obedience to guidelines is variable internationally and nationally, thus raising questions about their enforceability. They are, of course, not legally enforceable, but courts may be influenced by them, and variation must be evidence-based. Guidelines cannot logically be regarded as being set in stone; if that were the case, then there could be no innovation and medicine would not advance.  相似文献   
272.
Organic impurities of methamphetamine may show different patterns by synthesis. In the present study, we tried to find the impurities reflecting the conditions of synthesis by comparing impurity patterns of the methamphetamine samples synthesized by different methods. Sixteen methamphetamine samples were synthesized from ephedrine and pseudoephedrine by the three different manufacturing methods of Emde, Nagai and Moscow. The synthesized samples were extracted with ethyl acetate containing four internal standards, and the patterns of the organic impurities were investigated by GC-MS and GC-FID . Through the investigation, we found 10 peaks appearing in the latter part of GC chromatograms are characteristic to synthesis. The areas of the selected peaks were converted to the variables suitable for the statistical calculation, and the synthesized samples could be classified into four groups through the resultant cluster analysis.  相似文献   
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List of referees 1994–1995  相似文献   
276.
Parental reports of disagreements and serious disagreements about rules were examined in 200 families with seventh-grade boys and girls. No gender differences were found: Mothers did not report more disagreements than fathers; no more disagreements were reported for girls than boys. Disagreements about personal habits and family obligations were more common than disagreements about peer relations. Disagreements and serious disagreements, in general, were significantly correlated (positively) with parental reports of child oppositionalism and (negatively) with parents' satisfaction with parenting the target child, although some dyadic differences were found. Children's reports of parental acceptance were negatively correlated with disagreements only for the father-daughter dyad. Support was found for some of Baumrind's ([1968] Authoritarian vs. Authoritative Control,Adolescence 3: 255–272) notions regarding relations between rule frequency, child participation in rule making, and disagreements about rules, especially for the father-daughter dyad.The research reported here was funded in part by Father Flanagan's Boys Home, Inc., and by a grant to the senior author from the John D. and Catherine T. MacArthur Foundation, Family Relations in Early Adolescence.Received his Ph.D. in Clinical Psychology from Harvard University. Interests are the social psychology of adolescence and psychosocial adaptation to biological change.Received his Master of Science from Virginia Commonwealth University. Interests are family relations during adolescence, sex roles and their development, pediatric psychology, and statistical applications in psychology.  相似文献   
277.
Abstract

Presidents often give speeches about crime issues as a way to convince the public that there are significant problems for which an easy solution can be found. Studies have shown that presidential rhetoric on crime not only influences the public’s perception of the problem, but also the perception of the best solution. More recent research has demonstrated that presidents sometimes draw on the public’s fear of crime as a way to further affect the public’s perception of crime. In other words, presidents link crime with the public’s anxiety about other fearful events as a way to further impact the public’s perception of a problem (and thus further their agenda). This study examines presidential rhetoric on cybercrime to determine if executives link cybercrime with other issues such as national security. The findings provide credibility to both Cavelty’s threat frames approach as well as assertions made regarding the politics of fear.  相似文献   
278.
Forensic application of carbon isotope ratio measurements of honey and honey protein to investigate the degree of adulteration with high fructose corn syrup or other C4 plant sugars is well established. These measurements must use methods that exhibit suitable performance criteria, particularly with regard to measurement uncertainty and traceability – low levels of adulteration can only be detected by methods that result in suitably small measurement uncertainties such that differences of 1‰ or less can be reliably detected. Inter-laboratory exercises are invaluable to assess the state-of-the art of measurement capabilities of laboratories necessary to achieve such performance criteria. National and designated metrology institutes from a number of countries recently participated in an inter-laboratory assessment (CCQM-K140) of stable carbon isotope ratio determination of bulk honey. The same sample material was distributed to a number of forensic isotope analysis laboratories that could not participate directly in the metrological comparison. The results from these studies have demonstrated that the majority of participants provided isotope delta values with acceptable performance metrics; that all participants ensured traceability of their results; and that where measurement uncertainties were reported; these were fit-for-purpose. A number of the forensic laboratories only reported precision rather than full estimates of measurement uncertainty and this was the major cause of the few instances of questionable performance metrics. Reporting of standard deviations in place of measurement uncertainties is common practice outside metrology institutes and the implications for interpretations of small differences in isotopic compositions are discussed. The results have also highlighted a number of considerations that are useful for organisers of similar inter-laboratory studies in the future.  相似文献   
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