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991.
The act of evaluation requires an expenditure of resources. In Part I of this paper, we present a simple decision tree model borrowed from operations research to provide a conceptual framework for considering whether or not to commit such resources. In Part II, once the evaluation is carried out, we address the problem of evaluating the evaluation as a vehicle for producing useful information to decisionmakers. Evaluation inputs, processes, and outcomes are defined and discussed within the context of comprehensive evaluation of evaluations. 相似文献
992.
L McNally R C Shaler M Baird I Balazs L Kobilinsky P De Forest 《Journal of forensic sciences》1989,34(5):1070-1077
This study was designed to analyze the effects of the environment and substrata on the quality of deoxyribonucleic acid (DNA) isolated from evidentiary specimens. The quality of DNA isolated from actual casework specimens was determined by measuring its size by agarose gel electrophoresis. The information obtained could be used to predict the suitability of the DNA in the samples for restriction fragment length polymorphism (RFLP) analysis. The evidentiary specimens chosen for DNA were classified according to substrate (scrapings, plastic bags, synthetics, denim, and carpet) and according to a subjective evaluation of the condition of the stain (soiled, damp, or putrefied) and to its size (small or large). The results show that DNA of sufficient quality and high molecular weight (HMW) can be reliably isolated from bloodstains deposited on evidentiary items which have an unknown environmental history and which have dried onto a variety of substrata. Subsequent RFLP analysis of a selected number of these samples verified that the DNA was suitable for this type of analysis. 相似文献
993.
In the course of a scuffle, a youth of 18 years was struck a single blow across the chest with a golf club. He collapsed dead on the spot. At autopsy, a precisely located and highly distinctive patterned imprint abrasion of the precordial region was revealed providing an excellent match with the weapon. The heart showed multiple internal ruptures and there was a laceration of the lingula of the left lung. Injury to the chest wall was confined to the soft tissues, the rib cage and sternum being intact. We postulate a novel mechanism to explain the cardiac rupture. 相似文献
994.
995.
A rapid and efficient procedure is described for the extraction and analysis of oxazepam, the major urinary metabolite of diazepam in greyhounds. Urine was extracted by passing through a bonded silica column (Bond Elut) following enzyme hydrolysis. The adsorbed drug was eluted and then detected and measured by high performance liquid chromatography (HPLC). Recoveries were in excess of 85% at 50 ng/ml concentrations. Detection was possible up to 30 h after a single oral dose of diazepam (5 mg). 相似文献
996.
Blood cyanide concentration was determined in rabbits intoxicated orally or by inhalation. Experiments were carried out under urethane anaesthesia. In the inhalation experiments, rabbits inhaled a combustion product containing HCN via the tracheal cannula and in the oral studies animals were administered NaCN solution into the stomach. In addition to the carotid artery and jugular vein blood samples, postmortem samples were obtained from both sides of the heart and the descending vena cava. The arterial cyanide concentration in the inhalation group showed a close relationship with ventilation. After an initial rise, blood levels decreased a little, in some cases with transient apnea. At the last stage it again increased with gasping, reaching its maximal value. After ultimate apnea, the blood cyanide concentration declined. The blood cyanide values were higher in the oral group than in the inhalation group. The difference between the two groups became larger in the inferior order, the left heart blood--the right heart blood--blood in the descending vena cava. The left heart/right heart ratio of the inhalation group was significantly higher than that of the oral group (1.28+/- 0.28 vs. 0.95+/- 0.09). The coefficient of variation (c.v.) of the inhalation group was larger than that of the other group. Within the inhalation group, the left heart blood showed the largest c.v. values and this was probably due to redistribution of the cyanide by bloodstream after attainment of the maximal concentration. 相似文献
997.
998.
H C Lee R E Gaensslen H W Carver E M Pagliaro J Carroll-Reho 《Journal of forensic sciences》1989,34(1):7-14
Results obtained from the ABH grouping of bone tissues by the absorption-elution procedure and by a recently described two-dimensional absorption-inhibition procedure are reported. Neither the elution nor the inhibition procedure alone yielded uniformly correct results. A combination procedure consisting of the use of both absorption-elution and two-dimensional absorption-inhibition is proposed for bone ABH grouping. When elution and inhibition were used in combination, specimens yielding concordant results with both techniques were correctly grouped. 相似文献
999.
C Sakala 《Journal of health politics, policy and law》1990,15(4):709-753
After a hiatus in the early to mid-1980s, a growing number of policy leaders, policy organizations, and citizen groups are advocating programs that ensure basic medical care for all. Although a large literature examines the applicability to the U.S. of national medical care programs that have been established in other countries from the perspective of operations and effectiveness, little attention has been given to the applicability of the experience of other nations in securing these programs. This paper examines the development of national programs in the U.K. and Canada and addresses two questions. First, what factors were critical to the establishment of the British National Health Service and the Canadian hospital and physician insurance programs? Second, how applicable are those factors to current conditions in the U.S.? The paper reviews the roles played by dislocations in society, by established models of state-sponsored medical care programs, by political institutions and leaders, and by the major medical sectors. It shows that the U.S., while differing in many particulars, presents several parallels to the U.K. and Canada. The paper argues that the current environment in the U.S. offers the nation the opportunity to develop at state or local levels government-sponsored programs that guarantee basic medical benefits to all. A new and powerful coalition, moreover, may in the coming years advance the cause of broader, more substantive change at the national level. 相似文献
1000.
C Scorretti 《Zeitschrift für Rechtsmedizin》1983,91(2):153-157
A case of traumatic rupture of the anterior papillary muscle is presented. The patient survived for 3.5 h after injury without showing any serious cardiac symptoms, and in the absence of external chest injuries. Cardiac injury should always be suspected after a head-on collision, even if significant symptoms are missing. 相似文献