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281.
目的:观察不同离体时间对非血管化游离骨块同期种植在体内血管形成的情况,了解非血管化游离骨块离体后时间的长短对其植入体内后成活的影响。方法:截除狗下颌骨的无牙颌骨段,取自体非血管化的髂骨块,在离体10、20和80分钟内植入纯钛金属种植体,修复下颌骨的节段性缺损处,恢复下颌骨的连续性,分别在术后1,2,4周处死动物取材前用墨汁灌注和八因子抗原染色进行血管标记。结果:在术后1、2、4周的时间点,可见非血管化的骨块内墨汁灌注的血管数逐渐增多,标志血管的内皮细胞由团块状,同心圆状,逐渐向中空的血管样演变,离体10分钟和20分钟组之间有所差别,但没有统计学的意义,P>0.05;80分种组墨汁灌注血管较少,八因子标记的血管出现较晚,计数较少,与离体10和20分钟组之间有着显著的差异,P<0.05。结论:非血管化游离骨块同期种植体修复颌骨节段性缺损时,游离骨块的离体时间是影响血管生成的因素之一,离体时间越短越有利于血管的生成和移植骨的成活。 相似文献
282.
Molly Miranker M.A. 《Journal of forensic sciences》2016,61(5):1173-1179
The adult human pelvis is useful to estimate age because it contains three age indicators—the pubic symphysis, auricular surface, and acetabulum. This study tested the accuracy, inaccuracy, and bias of age estimation from the Suchey‐Brooks pubic symphysis, Osborne auricular surface, Rissech and Calce acetabulum aging methods, and a summary age of these indicators. The study sample consisted of 212 White individuals with known age and sex from the William M. Bass Donated Skeletal Collection. The Rissech method performed the best, was the most accurate method with smallest inaccuracy and bias, followed by the Osborne, Suchey‐Brooks, summary age, and then Calce methods. Though the Pearson correlation showed only the Suchey‐Brooks method to correlate significantly with known age, it is likely the Suchey‐Brooks study sample coincidentally reflected the age distribution of this test sample. Results suggested that Bayesian prediction may improve age estimation and should be applied to other age indicators. 相似文献
283.
Scott Dillon M.Sci. Craig Cunningham Ph.D. Paul Felts Ph.D. 《Journal of forensic sciences》2016,61(2):402-408
Many histological methods in forensic anthropology utilize combinations of traditional histomorphometric parameters which may not accurately describe the morphology of microstructural features. Here, we report the novel application of a geometric morphometric method suitable when considering structures without anatomically homologous landmarks for the quantification of complete secondary osteon size and morphology. The method is tested for its suitability in the measurement of intact secondary osteons using osteons digitized from transverse femoral diaphyseal sections prepared from two human individuals. The results of methodological testing demonstrate the efficacy of the technique when applied to intact secondary osteons. In providing accurate characterization of micromorphology within the robust mathematical framework of geometric morphometrics, this method may surpass traditional histomorphometric variables currently employed in forensic research and practice. A preliminary study of the intersectional histomorphometric variation within the femoral diaphysis is made using this geometric histomorphometric method to demonstrate its potential. 相似文献
284.
A Novel Forensic Investigation Applied to Bone Remains Exhumed near to Quirra Interforce Firing Range 下载免费PDF全文
Luca Roncati Ph.D. Antonietta M. Gatti Ph.D. Federico Capitani B.S. Goretta Bonacorsi Ph.D. Giuseppe Barbolini Ph.D. Antonio Maiorana Ph.D. 《Journal of forensic sciences》2016,61(3):858-861
The need to implement novel techniques, able to support a causal link between exposure and pathology, has been emerged over the recent years. The application of scanning electron microscope coupled with probe X‐ray microanalysis (by means of an energy‐dispersive spectroscopy) has been developed by our research group for the bone remains investigation. It was aimed to testify the exposure to microsized and nanosized pollutions, due to military activities in the Quirra interforce firing range, of a Sardinian shepherd, died of acute leukemia. Metallic debris with a combustive morphology and with an oncogenic potential has been surely detected inside his bone marrow canal. This novel technique has proved to be able to bring to light a source of past exposure preserved over time within the bone marrow canal. It can be useful for postmortem analyses, delivering a new avant‐garde approach to modern forensic science. 相似文献
285.
James H. Watterson Ph.D. D.A.B.F.T. Jolina E. Botman B.Sc. 《Journal of forensic sciences》2009,54(3):708-714
Abstract: Enzyme‐linked immunosorbent assay (ELISA) and liquid chromatography tandem mass spectrometry (LC/MS/MS) were used to detect diazepam exposure in skeletal tissues of rats (n = 15) given diazepam acutely (20 mg/kg, i.p.), and killed at various times postdose. Marrow, epiphyseal, and diaphyseal bone were isolated from extracted femora. Bone was cleaned, ground, and incubated in methanol. Marrow underwent ultrasonic homogenization. Extracts and homogenates were diluted in phosphate buffer, and then underwent solid‐phase extraction and ELISA. Relative sensitivity of detection was examined in terms of relative decrease in absorbance (ELISA) and binary classification sensitivity (ELISA and LC/MS/MS). Overall, the data showed differences in relative sensitivity of detection of diazepam exposure in different tissue types (marrow > epiphyseal bone > diaphyseal bone), which is suggestive of heterogenous distribution in these tissues, and a decreasing sensitivity with increasing dose‐death interval. Thus, the tissue type sampled and dose‐death interval may contribute to the probability of detection of diazepam exposure in skeletal tissues. 相似文献
286.
Lisa M. Misner M.S. Andrea C. Halvorson M.S. Jennifer L. Dreier M.S.F.S. Douglas H. Ubelaker Ph.D. David R. Foran Ph.D. 《Journal of forensic sciences》2009,54(4):822-828
Abstract: Mitochondrial DNA analysis of skeletal material is invaluable in forensic identification, although results can vary widely among remains. Previous studies have included bones of different ages, burial conditions, and even species. In the research presented, a collection of human remains that lacked major confounders such as burial age, interment style, and gross environmental conditions, while displaying a very broad range of skeletal degradation, were examined for both mitochondrial DNA (mtDNA) quality and quantity. Overall skeletal weathering, individual bone weathering, and bone variety were considered. Neither skeletal nor bone weathering influenced DNA quality or quantity, indicating that factors that degrade bone do not have the same effect on DNA. In contrast, bone variety, regardless of weathering level, was a significant element in DNA amplification success. Taken together, the results indicate that neither skeletal nor individual bone appearance are reliable indicators of subsequent mtDNA typing outcomes, while the type of bone assayed is. 相似文献
287.
Pierre Barrier M.D. Fabrice Dedouit M.D. José Braga Ph.D. Francis Joffre M.D. Ph.D. Daniel Rougé M.D. Ph.D. Hervé Rousseau M.D. Ph.D. Norbert Telmon M.D. Ph.D. 《Journal of forensic sciences》2009,54(4):773-778
Abstract: Thanks to recent advances, computed tomography is now seen as a tool of great value in the field of physical anthropology. In this study, we focused on the posterior pelvis and the auricular surface and evaluated the accuracy of 3D reconstructions of the auricular surface, using a methodology derived from a previous study by Lovejoy et al. We also looked for trabecular bone criteria expressing age‐related changes. Forty‐six coxal bones were scanned, and scoring of macroscopic criteria showed a good agreement between 3D reconstructions and photographs, especially for transverse organization (k = 0.90). The changes occurring in the posterior part of the sacropubic trabecular bundle were evaluated on CT reconstructions via three new criteria, which exhibited a good intra‐ and inter‐observer agreement (k = 0.77–0.89), and were particularly useful in identifying older subjects. We concluded that these CT‐evaluated trabecular bone criteria are promising and yield useful information about age at death. 相似文献
288.
Stephanie‐Marie Marciniak M.A. 《Journal of forensic sciences》2009,54(4):779-785
Abstract: This study assesses the degree of modification to the saw mark characteristics of dismembered skeletal remains when exposed to a controlled outdoor fire of limited duration. The sample consists of 36 adult pig hind limbs which were dismembered fleshed. Six handsaws and six power saws were used, with three limbs dismembered and burned for each of the saw types. Results indicate that fire exposure affects the visibility and identifiability of saw mark striae. With the handsaws, the bow saw, hacksaw, and keyhole saw were consistently recognizable. In the power saw group, the saw marks of the jigsaw, reciprocating saw, and chainsaw remained identifiable. Although the bone ends exhibited thermal alterations, the false starts were well preserved with minimal damage. Given the parameters of this study, it is possible to identify the class of saw based on the diagnostic characteristics present on the cremated bones. 相似文献
289.
290.
目的研究儿童骨骼的组织学特征,为儿童骨骼残片的法医学鉴定提供科学依据。方法提取儿童四肢长骨骨片,制作骨骼的组织切片,在显微镜下观察内、外环骨板,骨单位,骨细胞的组织学结构,比较儿童骨骼与动物及成人骨骼的组织学区别。结果儿童骨骼的骨单位形态与成人相似,骨单位间存在大量的内层骨板,与动物的骨组织特征相似。结论根据骨组织学特征,可以确定儿童的骨骼残片。 相似文献