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991.
On the basis of the data presented above the following conclusions may be drawn. 1. The molecular ion peaks of most of the compounds examined are relatively weak but usually easily discernible to permit molecular weight determination. 2. The mass spectra of benzilate esters exhibit a relatively intense peak at m/e 183, and monitoring of this ion can serve as a means for preliminary screening for the presence of this type of a system. 3. Related esters exhibit a similar type of fragmentation resulting in a fragment ion analogous to m/e 183 but shifted by the appropriate number of mass units according to the substituents present. 4. Cleavage of the piperidine ring-ester oxygen bond in 3 and 4-substituted isomers is followed by selective losses of hydrogen radicals to produce ions of type e, f, and g as indicated above. It is significant that in a related piperidine ring system (methylphenidate) substituted in the 2 position, the same type of cleavage results in no further hydrogen losses [16] because of charge stabilization from the ring nitrogen (ion j, Fig. 17) [17]. In other words, the tendency to form a conjugated ion following initial bond cleavage can serve as a means for identifying the position of substitution on the ring and for distinguishing positional isomers. 相似文献
992.
993.
L Ganzini B McFarland J Bloom 《The Bulletin of the American Academy of Psychiatry and the Law》1990,18(1):55-63
Mental health professionals have focused attention on the psychiatric sequelae of criminal victimization. This article compares the experience of white collar and violent crime victims on several parameters including statistical risk of victimization and psychiatric outcome after victimization. Emphasis is given to data obtained from interviewing 77 victims of a fraudulent financial scheme. 相似文献
994.
995.
996.
997.
B Janowitz S Wallace G Araujo L Araujo 《Journal of health politics, policy and law》1984,9(3):515-526
This paper examines factors associated with the cesarean birth rate, including medical condition and method of payment, in the largest maternity hospital of Fortaleza, Brazil. Data were collected on 5996 women who delivered at the Maternidade Escola Assis Chateaubriand from October 1980 to July 1981. All women were classified according to how they paid for their care: private (financed at least part of their care with own funds), insured (federal or state), or indigent. Private patients were found to be far more likely than patients in the other two groups to have cesarean deliveries, due primarily to the high percentage of private patients recorded as having prolonged or obstructed labor, combined with a high rate of prior cesarean sections. From this data, it appears likely that financial incentives did play a role in physician decisions on whether to perform cesarean deliveries. 相似文献
998.
In nearly all Asian countries services available to rural populations are inadequate and inappropriate. Improvement is crucial not only to fulfilling basic human needs, but for raising productivity and generating more broadly based economic development. This article reviews the types of obstacles in the way of improving service delivery, and assesses the strengths and weaknesses of the major institutional arrangements for delivering services. In the light of this review the article identifies four issues of major importance, first, the priority to be given to providing social and productive services; second, the most appropriate approach to delivering social and productive services; third, how to finance social services more effectively; and finally what alternative means there are of improving the administration of services. This article follows on from Part I which presented a comparative review of service needs in Asian countries. 相似文献
999.
Comparisons were made between 92 male prisoners over the age of 50 and 539 younger male prisoners at Utah State Prison, and between groups of first and muhiply incarcerated ot Utah and younger inmates. The older prisoners committed more crimes against persons, fewer property crimes, were older at first arrest, and were less socially deviant, impulsive, and hostile. The first incarcerated older inmates were found to have more often engaged in crimes of violence. were less involved in a criminal way of life, and were the best adjusted of all the groups. The multiply incarcerated older inmates were found to resemble the younger inmates in terms of a criminal way of life and were not different from their younger counterparts in their adjustment. 相似文献
1000.
A routine method is described for obtaining reproducible haptoglobin patterns from bloodstains by discontinuous polyacrylamide gel electrophoresis. By employing a stacking gel, proteins from bloodstain extracts are concentrated into narrow zones, before entering the resolving gel. This effect yields highly resolved haptoglobin patterns. Therefore, laboratories without the specialized equipment and expertise for polyacrylamide gradient gel preparation can still obtain highly resolved haptoglobin patterns from bloodstains. 相似文献