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With regard to the law, estimating fetal age is essential to assess viability (after 20 weeks according to the WHO) and the proposed methods generally use long bone measurements. Here, we evaluated the accuracy of soft tissue maturational stage and compared it with long bone measurements. First, eight kinds of tissues or organs from 448 fetuses with known medical history were studied (macroscopically or histologically). We clearly demonstrated that adrenal glands and skin were very good age indicators, because some characteristics appeared only after 20 weeks. We established a linear regression with a 95% confidence interval of +/- 2.9 weeks. Second, we applied our original formula using femur measurement and we combined soft tissues and bones in a multiparametric regression. The confidence interval was reduced to +/- 2.5 weeks. We conclude that the pathologist must use both histological and anthropometric data to determine fetal age as accurately as possible.  相似文献   

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The gestational age and/or viability of a fetus can become an important forensic issue. Several investigators have produced linear regression formulas based on crown-heel length (CHL), crown-rump length, or body diameters to determine gestational age. This study re-examines the relationship between fetal long bone length and CHL and tests a method of estimating CHL, and therefore gestational age, from radiographic measurements of the major long bone diaphyses. The results are compared with data based on dry bone measurements. Data from 252 cases confirm a strong correlation between all long bone lengths and CHL (> or = r = .9063; p < 0.01). Long bone length means for each CHL group are presented, as well as regression formulas for estimating CHL from radiographic measurements of the long bone diaphyses. The findings correspond closely with results based on a European sample, thereby validating that reference population as a normative sample for fetal analysis in the United States. The radiographic method can be used in instances where skeletal preparation is impossible or undesirable.  相似文献   

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目的研究成体马和成年人的股骨组织形态学结构,分析其组织学特征,建立人与马之间的种属鉴别方法。方法取来源于尸体检验的成人右股骨中段约4cm,同时收集马的右腿股骨,取中段约4cm,脱钙后制作成厚约25μm的骨组织切片,在光学显微镜下观察,将显微镜下的图像录入电脑,选取25项指标进行逐步判别分析。结果马和人在哈氏系统数量、哈氏系统直径等13个指标上具有显著差异,用这些指标建立种属判别数学模型,经盲测检验,二者的判别率可达99.6%。结论马和人的股骨组织学结构具有明显的种属特征,建立的判别方程可以有效地鉴别马和人的股骨碎片。  相似文献   

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The article deals with the method of determining the age of fingerprints elaborated in Poland. It consists in analysing the changes occurring in the perspiratory-adipose substance with lapse of time and enables to determine a presumable time of leaving the evidential traces on smooth and unabsorptive surface within the limits from 24 hours to a few years.  相似文献   

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Li CT  Li L  Liu Y 《法医学杂志》2006,22(5):346-348
目的检测不同年龄组人活体血细胞线粒体DNA4977碱基缺失情况及其与年龄的相关性。方法根据Anderson标准序列设计mtDNA恒定区和mtDNA4977特异缺失区引物,采用实时荧光定量PCR技术,对110份不同年龄组人活体血细胞mtDNA4977缺失水平进行检测。结果在23岁以下个体中未检出mtDNA4977缺失,在大于23岁的被检个体中检测到mtDNA4977缺失,年龄越大,越容易检测到缺失。结论人mtDNA4977缺失与年龄有一定的相关性。  相似文献   

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The issue of juvenile pornography has seen an increase in the past few years of the number of expert opinions requested to forensic pathologists, paediatricians and other various experts within the forensic and medical fields concerning the age of represented individuals. Regardless of the entity of the problem, no actual method exists which can allow us to give an objective and scientific answer, particularly in the postpubertal stage. Using parameters related to sexual maturation can be very dangerous. Nonetheless some experts still insist with similar types of “expertises”. This study aims at verifying the ability of different experts in assessing age of postpubertal individuals represented in pornographic material. Results underline the difficulties and major uncertainties of age evaluation by visual observation of photographic material particularly when the subjects have reached the sexual maturation stage – and therefore in verifying whether the individual is above or below 18 years of age (an important age limit for most European countries as far as this type of crime is concerned). Furthermore the study stresses the need both to search for an alternate approach and to apply extreme caution in judicial evaluation.  相似文献   

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Tooth wear is frequently used as a method of ageing skeletal remains. Fundamental to this method is the ability to measure the amount of tooth wear. The Brothwell chart based on the Miles method of ageing, uses simple ordinal scoring and is frequently used by archeologists. The purpose of the present investigation was to evaluate the accuracy of simple ordinal scoring in recording tooth wear and ageing skulls. A group of Chinese skulls of known age at death was used. The age range was from 16 to 60 years. A single score per molar tooth was used to record occlusal wear. The data were analysed by regression methods using BMDP statistical software. The results showed that molar tooth wear continues throughout the life of the individual. The first molar teeth wear significantly more quickly than do second molar teeth. Use of a simple ordinal score method for recording wear gives an inaccurate estimate of an individual skull's age at death with a very wide 95% confidence interval.  相似文献   

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The morphology of the sternal end of the right fourth rib has been proffered as an accurate age assessor in skeletonized individuals of both sexes. This technique was tested for its applicability on left and right II, III, V-IX. Tests were performed between phase scores obtained from right and left ribs; right rib IV phase scores and scores obtained from the others in the right rib series; and between right rib IV scores and a composite score composed of the average of an individual's phase scores (omitting rib IV). Left ribs IV-IX were found not to vary significantly from their right counterparts. Although only right rib II was found to vary significantly from rib IV, use of the other ribs in the series should be undertaken with caution due to questions concerning their statistical significance. A composite score is therefore recommended for use instead.  相似文献   

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It has been long recognized that cementum thickness increases with age. Much literature has recently been devoted to utilizing incremental lines in cementum as an aging criterion in animals, but only one study has been done suggesting this technique in humans. Thirty-one teeth of known age were histologically stained and sectioned to observe incremental lines. Direct predictions of age based on these lines underestimated the age of older specimens. However, there was a correlation between number of lines and age, and with a large enough specimen size, a computer-generated formula for age prediction may be possible.  相似文献   

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Adult age-at-death assessment is one of the most difficult problem encountered in paleoanthropology. Many procedures have been proposed using either skeletal remains or dental records, but most show systematic bias. Data processing of current methods are a source of error because they neglect that process of biological ageing is very variable between individuals and populations. The aim of this study is to test the potentiality of artificial neural networks (ANN) as a prediction tool. ANN have been used for a wide variety of applications where statistical methods are traditionally employed. But it performs better to solve linearly non separable patterns. We applied this technique after observation of several features' aging changes of the pubic symphysis and the auricular surface of the ilium. Although we failed to reduce the size of the intermediate class (30-59 years), the neural network identifies, with better reliability than previous works, the youngest (20-29 years) and the oldest (above 60 years) individuals.  相似文献   

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Stab-resistant body armour is now becoming a standard item of equipment for police officers in the United Kingdom. In the UK these are usually required to have a stab resistance as specified by the Police Scientific Development Branch KR42 standard [G. Parker, PSDB Stab Resistant Body Armour Test Procedure, Police Scientific Development Branch, Publication No 10/93, 1993]. There are several other test standards, all of which specify that body armour must resist penetration by a specific blade type delivered at a specific energy level or range of levels. However, the actual range of energy levels specified varies over almost an order of magnitude and the basis for these levels is not clearly defined. This paper describes tests to determine the energy range and characteristics of stabbing actions that might be directed against stab resistant body armour by an assailant. The energy and velocity that can be achieved in stabbing actions has been determined for a number of sample populations. Volunteers were asked to stab a target using an instrumented knife that measured the axial force and acceleration during the stabbing. The maximum energy obtained in underarm stabbing actions was 64 J whilst overarm stabbing actions could produce 115 J. The loads produced on contact with the target often approached 1000 N.  相似文献   

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In the literature, little is known about the applicability of this method in Turkish children. The aim of this study was, therefore, to evaluate the reliability of Demirjian method of age estimation when used for eastern Turkish children. A retrospective study was performed on a sample of panoramic radiographs taken from 807 healthy eastern Turkish children. The stages of dental maturity of the mandibular left seven permanent teeth for each subject using the eight radiographic dental maturity stages demonstrated by Demirjian were evaluated. A paired t-test was used for statistical analysis. The mean difference between the chronological and dental ages ranged from 0.2 to 1.9 years in girls and from 0.4 to 1.3 years in boys. The differences between the chronological and dental ages were statistically significant in all age groups. The applicability of Demirjian method is not suitable for eastern Turkish population.  相似文献   

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This paper presents an uncomplicated and minimally invasive method for age-at-death determination in a contemporary Dutch (West European) population, by modifying the approach of assessment based on the age-related remodeling of bone tissue. In contrast to the usual "osteon count," a "non-remodeled tissue count" is undertaken. To optimize the method, proper zeroing of the polarization filter set of the microscope is essential. Instructions for setting the filters are given. A sample of femoral shaft segments totaling 162 individuals with ages ranging from 15 to 96 years is analyzed. Subperiosteal quantitative assessments are recorded at the most anterior point of the femoral shaft and also at points 25 degrees to the left and to the right of that point. Interobserver agreement in the assessments shows an acceptable degree of correlation. Bone remodeling with age does not progress in a linear, but in a curvilinear manner. Dependence of predicted age on nonremodeled surface counts in the analyzed areas of the anterior cortex of the femur appears to be significant. A set of regression equations is given. Sex can be ignored in age prediction. The small but statistically significant dependence of predicted age on cadaver length corresponds with the present strong secular increase in stature in the Netherlands. A concise catalogue with micrograph examples for every 10-year period in life is available upon request.  相似文献   

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