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964.
In the last 35 years, organ transplant technology has advanced greatly. The major problem associated with organ transplantation is organ availability, and not surgery-related mortality. This article examines current organ procurement procedures and technologies, legislative responses to the scarcity of transplantable organs, as well as the psychological barriers to organ donation. Issues of fairness in the allocation of scarce economic and social resources, the role of religion and ethics in organ donation and transplantation decision, and the impact of the media are also considered.  相似文献   
965.
Various factors governing the detectability of explosive traces after being soaked in water were studied. The variables are: the type of the surface (surfaces liable to be found in aircraft were chosen), the type of explosive, the type of water (tap or seawater), and movement of the immersed surface in the water. The maximal immersion times (tmax) after which explosive detection was possible were evaluated. This datum was found to depend on the type of explosive (one of the important factors is solubility in water), the surface material and the environmental conditions (tap or seawater movement). Detection of PETN on high-density polyethylene, linoleum, glass and aluminum, by the chemical Explosive Testing Kit (ETK), was possible even after a month of soaking in seawater. In addition, it has been found that movement of bulk water around the samples with deposited explosives considerably decreases tmax values. It is, therefore, recommended to retrieve samples for explosive analysis as soon as possible and in areas where the currents of water is minimal.  相似文献   
966.
The influence of humidification in the ESDA process on subsequent development of fingerprints on paper items was studied. It was found that, while the DFO process is nearly insensitive to previous humidification, fingerprint development with ninhydrin or with indanedione can be significantly affected by previous humidification of the paper.  相似文献   
967.
We describe the origins, purposes, and findings of a national study to determine whether a large-scale program of blind proficiency testing in U.S. DNA laboratories is feasible and/or practical. Proficiency testing in clinical laboratories is reviewed, particularly as mandated by the Clinical Laboratory Improvement Acts and its role in the regulation of those laboratories. Proficiency testing in forensic urine drug testing labs is also briefly reviewed. Studies involving comparisons between open and blind proficiency testing are discussed. The clinical laboratory proficiency testing and regulation landscape provides the background for the DNA Act of 1994, and the congressional mandate to investigate blind proficiency testing in forensic DNA laboratories. Four models of blind proficiency testing are defined and discussed, along with the advantages and disadvantages of each and estimates of the costs of a large-scale program. The purposes of proficiency testing in a quality-assurance context are likewise discussed and related to the models and the arguments generally proffered for and against blind vs. open proficiency testing.  相似文献   
968.
Deaths of individuals being arrested are important and complex medicolegal cases. Conclusions regarding the cause and manner of death for such cases must take into account multiple factors that may have played a role, as well as anticipate the forensic issues that will arise. In this article, we review the deaths of 2 individuals in which phencyclidine intoxication was a factor that contributed to death during arrest. Most cases of sudden death during arrest have involved cocaine intoxication; because phencyclidine's pharmacologic properties are quite different from those of cocaine, these cases allow for comparisons to those factors that may have greater importance.  相似文献   
969.
Treatment for individuals suffering from migraines and pain due to an inflammation or impingement of a nerve range from noninvasive methods such as massage, physical therapy, and medications to invasive methods such as epidural steroid injections and surgery. Each method of treatment has an associated level of risk. While minor to moderate complications from such procedures do occur, deaths are very rare. We report the first cited case of a death associated with the pain management procedure called nerve root block, also referred to as a transforaminal epidural steroid injection. We present the medical history and autopsy findings of a 44-year-old white female who died of massive cerebral edema secondary to the dissection of the left vertebral artery and subsequent thrombosis due to the perforation of that artery by a 25-gauge spinal needle during a C-7 nerve root block.  相似文献   
970.
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