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961.
962.
The reconstruction of the health system in Afghanistan is in its early stages, and donors have proposed Performance-based Partnership Agreements (PPAs) through which to subcontract the delivery of health services to private organisations, both for-profit and not-for-profit. Beyond ideological debates, this article sets out to explain the model underlying the PPA initiative and sheds light on empirical data concerning the assumed benefits of such an approach. The article studies privatisation and the contracting-out of health services, though there is as yet no information that can demonstrate the superiority of private over public service provision. Similarly, the merits of subcontracting have not been fully proven and such arrangements raise several ethical issues. Where PPAs are to be attempted, it is important to remain cautious and to ensure that operations are organised in such a way as to permit proper comparison. The paper concludes with recommendations to organisations involved in or considering the advantages of PPAs.  相似文献   
963.
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The estimation of chronological age in cadavers, human remains and in living human beings by various methods is discussed. These methods, which are based on the age dependent non-enzymatic changes of l-form amino acids to d-form amino acids, mainly aspartic acid, are among the most reliable and accurate methods to date. Most of these methods use gas chromatography (GC). In this review, results of aspartic acid racemization in dentin at different targets are discussed. In addition, pre-considerations and guidelines are given for the selection of dentin from teeth. A pilot project was run to evaluate the efficiency of high performance liquid chromatography (HPLC) coupled with fluorescence detection. New buffer conditions were found to obtain stable derivatives of aspartic acid enantiomers for the estimation of racemization.  相似文献   
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Postmortem investigation is increasingly supported by computed tomography (CT) and magnetic resonance imaging, in which postmortem minimal invasive angiography has become important. The newly introduced approach using an aqueous contrast agent solution provided excellent vessel visualization but was suspected to possibly cause tissue edema artifacts in histological investigations. The aim of this study was to investigate on a porcine heart model whether it is possible to influence the contrast agent distribution within the soft tissue by changing its viscosity by dissolving the contrast agent in polyethylene glycol (PEG) as a matrix medium. High-resolution CT scans after injection showed that viscosities above c. 15 mPa s (65% PEG) prevented a contrast agent distribution within the capillary bed of the left ventricular myocardium. Thereby, the precondition of edema artifacts could be reduced. Its minimal invasive application on human corpses needs to be further adapted as the flow resistance is expected to differ between different tissues.  相似文献   
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