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991.
Vertebral artery removing constitutes a significant forensic pathology challenge. Dissection techniques during head-neck autopsy are based on anterior approach, a difficult method, which is unable to assess the transverse part of the artery. This work presents an original and simple method for dissecting vertebral arteries by a posterior approach, opening the vertebroarterial canal through the spinal canal without any special equipment. Once the spinal cord is removed, the transversarium foramens are opened by an internal cut at the pedicle and an external cut at the transverse process. This enables us to visualize vertebral arteries in its entirety. The method improves both the examination of the upper extracranial segment of the vertebral artery and the neuropathological study when arterial injury is suspected. Applying this method routinely is both feasible and useful in suspected cases of vertebral artery trauma and could contribute to assess more precisely the actual incidence of this injury.  相似文献   
992.
Prolapse rectum (PR) or protrusion of the rectum beyond the anus occurs frequently in populations at both extremes of age. In the pediatric population, in developed countries, the commonest cause for PR is thought to be cystic fibrosis (CF). Treatment options for CF include conservative management, surgical resection and fixation, suturing, and injection sclerotherapy (IS). The last is considered an attractive treatment option because it is minimally invasive. In this case report, the authors present the details about a 2-year-old female child, with PR and CF, who died after IS, using phenol as the sclerotherapeutic agent. Autopsy findings and toxicology tests performed to establish phenol toxicity are documented. The available literature is reviewed. This case report underscores the risks of using phenol for IS and emphasizes the point that the procedure is not innocuous and an adverse outcome including fatality is a possibility.  相似文献   
993.
Forensic identification techniques include the examination of ID cards, the decedent's private belongings, fingerprints, footprints, lip marks, dental findings, red blood cell enzymes, performing photograph matching, facial reconstruction, visual identification, and DNA "fingerprinting." As part of forensic examinations, the identification of corpses that are fresh, decomposed, fragmented, or skeletonized as well as individual body parts and human remains can be requested. Identification becomes a challenging task for forensic terms particularly in mass-disaster situations. Each identification case should be considered to its own merit and the way to do that should be based on the effectiveness and cost of each method used. In Turkey, one of the major duties of the medicolegal system on the investigation of deaths is to identify the deceased if unknown.This study is undertaken to investigate the procedures, as well as their validities, used to deal with individualization of dismembered bodies directly sent to the Council of Forensic Medicine, Ministry of Justice, for autopsy and/or visual identification, as well as those received from peripheral districts for forensic identification. According to the Turkish Penal Procedural Law, a positive identification of the deceased is mandatory before performing an autopsy. According to the law, the ID cards are not taken to be sufficient for recognition of the deceased, and the major way of identification in daily practice is visual identification by a relative or any recognizant person to approve the identification to the prosecutor. If visual identification fails, fingerprints, dental x-rays or body x-rays, and DNA "fingerprinting" can be used to establish identity when compared with known records of the individual obtained by law enforcement.This retrospective study was carried out into 421 dismembered bodies, among 3063 autopsies performed in year 2002 by the Department of Morgue at the Council of Forensic Medicine, with particular insight into the identification procedures undertaken and their results. The overall negative identification rate was 30.4%, and in 1% of the cases, the visual identification by relatives were not confirmed by DNA identification and taken as misidentified.  相似文献   
994.
The easily available "legal highs", which are products containing psychoactive substances, such as cathinones, piperazines and synthetic cannabinoids, are abused by adolescents in Poland and in the world as alternatives to classic drugs, such as amphetamines or marijuana. The majority of these potentially dangerous substances are still legal and they are associated with a risk of severe poisoning or even death, and provide new challenges in clinical and forensic toxicological practice. Investigations in the field of "designer drugs" may be well illustrated by the case of a suicide of a 21-year old male who ingested a specified dose of a preparation called "Amphi-bi-a" that contains bk-MBDB, chemically 2-methylamino-1-(3,4-methylenedioxyphenyl) butan-1-one, which belongs to the cathinone group, as a synthetic euphoric empathogen and psychoactive stimulant that is chemically similar to MDMA. It is one of more common components of "legal highs" examined in Poland and other countries. The documentation of the case includes a clinical assessment of the patient's health status performed during his almost 4-h hospitalization before death, autopsy and histological examinations supported by toxicological findings revealing bk-MBDB at extremely high concentrations (at 20mg/l in the blood and 33mg/kg in the liver); hence, this body of evidence contributes to knowledge in the field of "designer drugs". Inventions of designers of new psychoactive xenobiotics, which are much in demand, especially in view of the dynamic Internet marketing, which drums up narcobusiness, must be balanced by a national strategy developed by medical, legal and educational circles in the modern civilized world in order to prevent the spreading of the phenomenon.  相似文献   
995.
We study in this paper the expanding behaviour of hollow point 9 mm Parabellum projectiles (Hornady XTP(?) and Speer Gold Dot(?)). We defined a deformation rate that takes into account both the diameter increase and the length reduction. We plotted the behaviour of this parameter versus impact velocity (we refer to this curve as the expanding law). This expanding law has been plotted for different gelatin weight ratios and different gelatin block lengths. We completed our experiments with a set of high speed movies in order to correlate the deceleration to the state of expansion and size of the temporary cavity. Our results pointed out that full expansion is reached shortly after the projectile fully penetrates the gelatin. This result shows that the key point to accurately simulate human body interaction with a hollow point projectile is to accurately simulate the interface (skin, skull, clothes thoracic walls). Simulating accurately organs is only an issue if a quantitative comparison between penetration depths is required, but not if we only focus on the state of expansion of the projectile. By varying the gelatin parameters, we discovered that the expanding law exhibits a velocity threshold below which no expansion occurs, followed by a rather linear curve. The parameters of that expanding law (velocity threshold and line slope) vary with the gelatin parameters, but our quantitative results demonstrate that these parameters are not extremely critical. Finally, our experiments demonstrate that the knowledge of the expansion law can be a useful tool to investigate a gunshot in a human body with a semi-jacketed projectile, giving an estimation of the impact velocity and thus the shooting distance.  相似文献   
996.
997.
Knowledge regarding the succession patterns of insects that visit carcasses as well as the other arthropod that colonise them and analysis of the parameters that are associated with larvae allow calculation of the minimum postmortem interval (PMI). This information is obtained from experiments carried out under specific geoclimatic conditions, which determine their application in forensic environments under similar conditions. The field study presented here is the first in Chile to analyse the decomposition process of pig carcasses and the associated succession of insects, colonising species and parameters related to larval masses. All of the larvae obtained from daily samples were measured (in mm), and their mean, range, standard deviation and stage of development (instars) were determined. The carcasses reached the dry remains stage in only 11 days. Seven species of Diptera visited the carcass during the process, but only two species colonised it by means of egg deposition followed by development of larvae: Cochliomyia macellaria (Fabricius) and Lucilia sericata (Meigen) (Diptera: Calliphoridae), which exhibited a duration of the development cycle from egg to adult of 21 days. The collected Coleoptera correspond to five predator species (Staphilinidae and Histeridae). From the results of this study, it can be concluded that only some of the insect species present in this region can provide information that can be used in forensic entomology and that analysis of larval masses of colonising species can be a valuable tool for determining the PMI(min) in this region of Chile.  相似文献   
998.
The in vitro production of GHB was observed in freshly collected, untreated whole blood samples using glass BD-Vacutainers and polypropylene S-monovettes. GHB concentrations were determined daily over a period of one week and after 3, 6 and 9 weeks again. Furthermore, the GHB concentration in 40 untreated random whole blood samples stored at 4°C for a longer period of time (10 samples 12 month, 10 samples 24 month and 20 samples 36 month) was also determined. For comparison, the in vitro production of GHB in freshly collected and prepared serum samples was observed. GHB serum concentrations were determined three times over a period of one week and once again after six weeks. Sample preparation was performed by means of methanolic extraction following the precipitation of whole blood and serum samples. A methanolic standard calibration was done in a low range of 0.005-0.1 μg/mL (LOD: 0.004, LLOQ: 0.013). For quantification a spiked blood bank serum with a determined GHB concentration of 0.09 μg/mL was used. Corrected calibrations in the range of 0.09-5.09 μg/mL were used (LOD: 0.08 μg/mL, LLOQ: 0.30 μg/mL), recovery: 91.3% (high level: 4.09 μg/mL) 50.5% (low level: 0.19 μg/mL). RESULTS: Relevant elevation of GHB was observed in all whole blood samples stored in liquid form (4°C or room temperature). In two of the 40 whole blood samples stored over a longer period of time at 4°C, GHB concentrations in the range of 13 μg/mL were even determined. These findings constitute grounds for caution. Even a GHB cut-off level of 5 μg/mL cannot be considered as "absolutely positive" proof of a case of exogenous administration, at least in untreated liquid blood samples in long time storage. However, no significant elevations of GHB were otherwise observed in any of the serum samples independently of storage temperature nor in the whole blood samples that were frozen for storage. CONCLUSIONS: The results suggest that the cut-off for exogenous GHB of 5 μg/mL could be lowered significantly, with the consequence of winning valuable time for the potential victim, but only if serum is collected for GHB determination or if the whole blood sample is frozen immediately after collection and the procedure well documented.  相似文献   
999.
The growth of five variables of the tibia (diaphyseal length, diaphyseal length plus distal epiphysis, condylo-malleolar length, sagittal diameter of the proximal epiphysis, maximum breadth of the distal epiphysis) were analysed using polynomial regression in order to evaluate their significance and capacity for age and sex determination during and after growth. Data were collected from 181 (90♂ and 91♀) individuals ranging from birth to 25 years of age and belonging to three documented collections from Western Europe. Results indicate that all five variables exhibit linear behaviour during growth, which can be expressed by a first-degree polynomial function. Sexual significant differences were observed from age 15 onward in the two epiphysis measurements and condylo-malleolar length, suggesting that these three variables could be useful for sex determination in individuals older than 15 years. Strong correlation coefficients were identified between the five tibial variables and age. These results indicate that any of the studied tibial measurements is likely to serve as a useful source for estimating sub-adult age in both archaeological and forensic samples.  相似文献   
1000.
Traumatic vertebral artery dissection is not often seen by forensic pathologists, and cases investigated are scarce in the forensic literature. We present the case of a 40-year-old woman cyclist who was struck by a car while wearing a helmet, and was neurologically near normal immediately thereafter at Emergency. She presented 48 h later with acute right hemiparesis, decreasing level of consciousness, and unsteadiness. CT revealed massive cerebellar infarction. CT angiography was normal. The patient died in coma 7 days after injury and autopsy revealed bilateral edematous cerebellar infarction and bilateral vertebral artery dissection. Rotational neck injury and mural tear in the wall of the Atlantic parts of both vertebral arteries is suggested as the possible mechanism of the arterial injury. Head and neck injuries are reported as a precipitating cause of vertebral artery injury. The possible influence of trauma may be further underestimated if longer intervals between vessel dissection and ischemia occur. The current case illustrates that "talk-and-die" syndrome may be due to occult vertebral artery dissection, possibly bilateral. In forensic cases of delayed death after mild trauma to the head and neck, the vertebral arteries should be examined for the cause of death.  相似文献   
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