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451.
Hypernatremia has been causally linked with subdural hematoma (SDH), but more recently this has been called into question. Conversely, there is a well-established link between SDH and injury. We wish to examine the evidence base that hypernatremia in infants and young children causes SDH.We present 2 cases of children with severe hypernatremia whose intracranial contents were assessed by imaging in the first case and postmortem examination in the second. Neither demonstrated SDH. The first case was important as the hypernatremia was iatrogenic occurring in a controlled hospital environment.We also searched the literature from 1950 to 2007, collecting data on all reported cases of hypernatremia in children younger than 7 years whose intracranial contents were examined by imaging, surgery, and/or postmortem examination. Of 124 cases reported in 31 articles, 112 cases developed hypernatremia in the community, and 12 in the hospital. Subdural hematoma was demonstrated in 7 cases, all of which had developed hypernatremia in the community under circumstances that would make it difficult to exclude nonaccidental injury. None of the 12 cases that developed hypernatremia in a controlled hospital environment had SDH.The evidence base supporting the hypothesis that hypernatremia causes SDH is poor, depending on isolated reports with uncertain histories.  相似文献   
452.
Posttraumatic stress disorder (PTSD) is common among maltreated youth but it remains unclear as to whether removal from home is as traumatizing as the maltreatment. This study examined 250 maltreated adolescents aged 11–17?years who were grouped on the basis of whether they (1) endorsed removal from home as their primary traumatic event, (2) endorsed removal from home as a secondary traumatic event, but not their primary traumatic event, or (3) did not endorse removal from home as traumatic. PTSD diagnoses as well as symptoms of PTSD, dissociation, depression, posttraumatic cognitions, and anger expression were measured. Adolescents who endorsed removal from home as their primary traumatic event reported significantly lower levels of PTSD and related symptoms than adolescents in the other groups. The findings are discussed within the context of transactions surrounding removal from home and support previous work that PTSD is a critical concern regarding many maltreated youth.  相似文献   
453.
This report provides an overview of the injuries caused by a unique blade‐type weapon known as a cane sword. The cane sword usually consists of a blade that is stored in a cylindrical “cane” that can be released at the handle to reveal the hidden blade within. The victim of the case was found to have a stab wound in the left mid‐back that caused perforation of both the lower and upper lobes of the left lung, resulting in a left hemothorax. Upon autopsy, it was concluded that the patient died from injuries caused by the stab wound to the back. Given the shape of the wound and the fact that the weapon itself was found at the site of the homicide, the weapon that caused the injury was believed to be a cane sword. This case will inform forensic pathologists, law‐enforcement officers, emergency medical personnel, and physicians about rare weapon, the cane sword.  相似文献   
454.
Polymerase chain reaction (PCR)-based STR DNA typing systems are used extensively in the field of human identification. Under optimal PCR conditions, the amplicon yield from both alleles of an STR locus is expected to be approximately equivalent. However, it is reasonable to expect that rare genomic sequence polymorphisms will co-localize with well-designed primer sets and induce allele imbalance or "dropouts". Two samples were identified in the course of genotyping thousands of individuals with AmpF/STR Profiler Plus that showed strong disparity in amplitude peak height of heterozygous peaks at the loci vWA and FGA. These samples were reamplified at reduced annealing temperature in an attempt to balance the peak heights. Nucleotide sequencing documented polymorphisms at the PCR primer binding sites of the affected alleles. The results indicate that reducing the annealing temperature to improve primer-binding efficiency at the mismatch and employing an alternative multiplex enhanced the data from both samples. Reducing annealing temperatures could provide a simple general solution to improving data quality for samples where polymorphisms are suspected to cause allele imbalance. Finally, we report on additional polymorphisms surrounding the vWA locus in a genetically diverse population.  相似文献   
455.
Non-Reproductive Human Cloning (NRHC) allows researchers to develop and clone cells, including non-reproductive cells, and to research the etiology and transmission of disease. The ability to clone specific stem cells may also allow researchers to clone cells with genetic defects and analyze those cells with more precisions. Despite those potential benefits, Parliament has banned such cloning due to a myriad of social and ethical concerns. In May 2002, the Canadian Government introduced Bill C-13 on assisted human reproductive technologies. Bill C-13 deals with both the scientific and the clinical use of human reproductive materials, and it prohibits a number of other activities, including NRHC. Although the Supreme Court of Canada has never ruled on whether scientific experiments area form of expression, academic support exists for this notion. The authors go through the legal analysis that would be required to find that scientific experiments are expression, focusing in part on whether NRHC could be considered violent and thus fall outside the protection of section 2(b). The latter question is complicated by the ongoing policy debate over whether an "embryonic cell" is property of human life. The authors then consider whether a ban on NRHC could be justified under section 1 of the Charter. They conclude that both the breadth of the legislative purpose and the proportionality of the measure are problematic. Proportionality is a specific concern because the ban could be viewed as an outright denial of scientific freedom of expression. Although consistent with current jurisprudence on freedom of expression, this paper runs against the flow of government policy in the areas of regulation and prohibition of non-reproductive human cloning. As there has been no Charter litigation to date on whether scientific research is a form of expression, the authors introduce a new way of looking at the legality of the regulation of new reproductive technologies.  相似文献   
456.
Examination of stomach contents is one of the important steps in medical legal autopsy. Vegetative materials such as stems, roots, and seeds in stomach contents can be valuable evidence for providing investigative leads in death investigation. Currently, the identification of plant materials relies on microscopic and morphologic examination. We have found that many seeds are often protected from acid degradation during stomach digestion by their tough exterior seed coat. Tomato seeds were selected as a model system to assess DNA analysis and plant variety marker identification. The DNA-amplified fragment length polymorphism method was performed to determine if the DNA obtained from single seeds could be used for PCR analysis. From the amplified fragment length polymorphism results, some candidate markers for individualizing seeds from morphologically distinct tomatoes were identified. These data on DNA analysis of tomato seeds indicate amplified fragment length polymorphism is a viable procedure for the individualization of seeds from stomach contents in forensic investigations.  相似文献   
457.
Psychological maltreatment, including verbal aggression, has been implicated as an important contributor to children's behavioral problems. The present study looked specifically at the relationship between different forms of maternal verbal aggression and their association with children's adjustment. Mothers from Violent and Nonviolent families were compared on their use of various verbal aggression tactics, as measured by the Conflict Tactics Scale (Straus, 1979). Mothers from both groups used threats and insults with comparable frequency. In both groups, insults were predictive of children's adjustment. The relationship was particularly striking in children from violent homes. We conclude that chronic exposure to inter-parental violence may render children emotionally susceptible to maternal disparagement.  相似文献   
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460.
The National Institute of Justice (NIJ) and the National Aeronautics and Space Administration's (NASAs) Goddard Space Flight Center (GSFC) have teamed up to explore the use of NASA developed technologies to help criminal justice agencies and professionals solve crimes. The objective of the program is to produce instruments and communication networks that have application within both NASA's space program and NIJ programs with state and local forensic laboratories. A working group of NASA scientists and law enforcement professionals has been established to develop and implement a feasibility demonstration program. Specifically, the group has focused its efforts on identifying gunpowder and primer residue, blood, and semen at crime scenes. Non-destructive elemental composition identification methods are carried out using portable X-ray fluorescence (XRF) systems. These systems are similar to those being developed for planetary exploration programs. A breadboard model of a portable XRF system has been constructed for these tests using room temperature silicon and cadmium-zinc telluride (CZT) detectors. Preliminary tests have been completed with gunshot residue (GSR), blood-spatter and semen samples. Many of the element composition lines have been identified. Studies to determine the minimum detectable limits needed for the analyses of GSR, blood and semen in the crime scene environment have been initiated and preliminary results obtained. Furthermore, a database made up of the inorganic composition of GSR is being developed. Using data obtained from the open literature of the elemental composition of barium (Ba) and antimony (Sb) in handswipes of GSR, we believe that there may be a unique GSR signature based on the Sb to Ba ratio.  相似文献   
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