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991.
The carotid bodies tend to enlarge after long-standing cardiopulmonary disease. Our objective was to investigate whether cardiac hypertrophy is associated with carotid body hyperplasia. Fifteen autopsy cases with combined left and right ventricular hypertrophy were examined and compared with two control groups (16 cases). The study involved a meticulous dissection of carotid bifurcations, thin serial sections, and morphometric analysis of carotid body volume and cell types (progenitor, dark, light, and sustentacular). There was a significant increase in sustentacular cells in all individuals with cardiac hypertrophy, which was not drug-induced, and accompanied by a similar increase in carotid body volume. Dark or light cell accumulation was detected focally and only in three instances. It appears that the generalized sustentacular cell hyperplasia is the result of long-standing hypoxia, while a superimposed focal prominence of dark or light cells may be proliferative or metaplastic in nature and attributed to short-term hypoxia.  相似文献   
992.
The aims of this study were to determine if dynamic parameters (duration, size, velocity, jerk, and pen pressure) differed for signing style (text-based, stylized, and mixed) and if signing style influences handwriting dynamics equally across three signature conditions (genuine, disguised, and auto-simulation). Ninety writers provided 10 genuine signatures, five disguised signatures, and five auto-simulated signatures. All 1800 signatures were collected using a digitizing tablet resulting in a database of each signature's dynamic characteristics. With genuine signatures, there were significant differences between styles for size, velocity, and pen pressure, and there were significant differences between genuine signatures and at least one of the un-natural signature conditions for all parameters. For velocity and size, these changes with condition were dependent on style. Changes with condition for the other parameters were similar for the three styles. This study shows that there are differences among natural signature styles and disguise behaviors that may be relevant in forensic signature examinations.  相似文献   
993.
Canines are usually used in anthropological and forensic sciences for sex and age determination. The best methods to estimate age are based on secondary dentine apposition, evaluated from periapical X-rays. The aim of this study was to propose a new method of sex and age estimation using 3D models to obtain more precise predictions using tooth volumes. Fifty-eight dental CT scans of patients aged 14-74 with a well-balanced sex ratio composed the sample. One hundred and thirty-three healthy canines were modeled (Mimics 12.0). The sample was divided into a training sample and a validation sample. An age formula was determined using the "pulp volume/tooth volume" ratio. Sex prediction was adjusted with total volumes. Applying the equations to the validation sample, no significant difference was found between the real and predicted ages, and 100% of the sex predictions were correct. This preliminary study gives interesting results, and this method is worth being tested on a larger data sample.  相似文献   
994.
In considering psychiatric evidence, criminal justice systems make considerable use of labels from official psychiatric classificatory systems. There are legislated requirements for psychological and/or behavioural phenomena to be addressed in legal tests, however medico-legal use of the current categorical diagnostic frameworks which are increasingly complex is difficult to justify. The lack of validity in large domains of the present classificatory systems is now more openly acknowledged, prompting a critical rethink. Illustrative examples include post-traumatic stress disorder, various personality disorders, and dissociative identity disorder. It follows that the Courts' faith in the present categorical classifications (e.g., DSMIV and ICD10) is misplaced and may be ultimately unhelpful to the administration of justice.  相似文献   
995.
We report the occurrence of a clinically undiagnosed biatrial myxoma with left ventricular involvement in a 2-month-old male infant, resulting in sudden death. During a routine well-baby examination, a grade (34) holosystolic murmur was detected at the left sternal border with radiation to the axilla and back. On the following day, the patient collapsed and died suddenly. An autopsy revealed a large multifocal neoplasm diffusely involving the aortic valve while displaying mitral, tricuspid, and left ventricular extensions. The ensuing histopathologic and immunohistochemical studies were diagnostic for myxoma. We discuss the occurrence of cardiac myxoma within the pediatric population and review the literature as to theorize whether this lesion was a congenital process versus a rapidly growing tumor that developed after the child was born. Lastly, we address the potential for sudden death in patients with such tumors.  相似文献   
996.
Although many cases of fatal hydrogen sulfide poisoning have been reported, in most of these cases, it resulted from the accidental inhalation of hydrogen sulfide gas. In recent years, we experienced 17 autopsy cases of fatal hydrogen sulfide poisoning due to the inhalation of intentionally generated hydrogen sulfide gas. In this study, the concentrations of sulfide and thiosulfate in blood, urine, cerebrospinal fluid and pleural effusion were examined using GC/MS. The sulfide concentrations were blood: 0.11-31.84, urine: 0.01-1.28, cerebrospinal fluid: 0.02-1.59 and pleural effusion: 2.00-8.59 (μg/ml), while the thiosulfate concentrations were blood: 0-0.648, urine: 0-2.669, cerebrospinal fluid: 0.004-0.314 and pleural effusion: 0.019-0.140 (μmol/ml). In previous reports, the blood concentration of thiosulfate was said to be higher than that of sulfide in hydrogen sulfide poisoning cases, although the latter was higher than the former in 8 of the 14 cases examined in this study. These results are believed to be strongly influenced by the atmospheric concentration of hydrogen sulfide the victims were exposed to and the time interval between exposure and death.  相似文献   
997.
Chen F  Chen Y  Yu Y  Qiang Y  Liu M  Fulton D  Chen T 《Forensic science international》2011,212(1-3):272.e1-272.e6
The purpose of this study was to acquire accurate data of craniofacial soft tissue thickness (CFSTT) and nasal profile in Chinese people of Han population. A total of 31 anatomical landmarks and 4 nasal profile parameters were determined using magnetic resonance imaging (MRI) in 425 subjects (233 males and 192 females). In the present study, the mean CFSTT values of male subjects exceeded those of female subjects at most anatomical landmarks except at seven (22.58%) and 6 out of the 7 landmarks were bilateral anatomical landmark points. The age-related and sex × age interactions were found to be statistically significant at all landmarks. Significant differences were found in the nasal profile data of males and females, and 15 out of 20 different groups had significant differences between sexes, and the mean values of nasal length, nasal height, nasal depth and nasal breadth in males were all greater than those in females. Furthermore, both CFSTT and nasal profile showed good correlation with age. The thickest CFSTT of male and female were found at the respective ages of 45-59 and 35-44, and the nasal profile becomes more constant after 24 years of age. CFSTT of the lower part of the face shows greater variation compared to the upper part, so special care needs to be applied when reconstructing the lower portion of the face. Our data on CFSTT and nasal profile for the Chinese Xi'an Han population is important in understanding craniofacial characteristics of the Chinese population and might be potentially helpful in forensic identification.  相似文献   
998.
This paper analyses and discusses arguments that emerge from a recent discussion about the proper assessment of the evidential value of correspondences observed between the characteristics of a crime stain and those of a sample from a suspect when (i) this latter individual is found as a result of a database search and (ii) remaining database members are excluded as potential sources (because of different analytical characteristics). Using a graphical probability approach (i.e., Bayesian networks), the paper here intends to clarify that there is no need to (i) introduce a correction factor equal to the size of the searched database (i.e., to reduce a likelihood ratio), nor to (ii) adopt a propositional level not directly related to the suspect matching the crime stain (i.e., a proposition of the kind 'some person in (outside) the database is the source of the crime stain' rather than 'the suspect (some other person) is the source of the crime stain'). The present research thus confirms existing literature on the topic that has repeatedly demonstrated that the latter two requirements (i) and (ii) should not be a cause of concern.  相似文献   
999.
1000.
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