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381.
目的 测定不同产地知母须根中新芒果苷、芒果苷和异芒果苷的含量。方法 采用高效液相二极管陈列检测法,Shim-pack色谱柱(4.6 mm ×250 mm,5 μm);乙腈-0.4%冰醋酸水溶液梯度洗脱,流速1. 0 mL/min;柱温25 ℃;检测波长为258 nm。结果 所收集的知母须根样品中新芒果苷的含量为1.2%~1.9%,芒果苷的含量为1.0%~1.6%,异芒果苷的含量为0.4%~0.6%。结论 知母须根中(口山)酮成分含量较高,在知母须根的综合开发利用中可考虑此类成分。  相似文献   
382.
Gender determination is a fundamental issue in forensic anthropology. Many techniques based on bone and dental remains have been proposed. It is not always possible to implement the techniques using bones, but teeth are often perfectly preserved. It has been demonstrated that the canine has the greatest sexual dimorphism, and the aim of this work was to provide an easy and accurate dental technique for determining the gender in the absence of other skeletal elements. The sample was composed of 210 CT scans with four healthy canines. The 840 canines were modeled using MIMICS® 10.01 software. The total volume of each tooth was determined. Seven mathematical models were determined by binary logistic regressions and ranked in order of relative performance. The seven proposed predictive models thus performed (0.910 ≤ AUC ≤ 0.938), with overall rates of correct predictions between 82.38 and 85.24%. The 4‐canine model is the most powerful for predicting the gender.  相似文献   
383.
Abstract: Numerous methods for establishing a biological profile exist; however, many of these methods rely on the recovery of several specific bones or on fragile skeletal elements that are sometimes irrecoverable. It is for this reason new methods utilizing other previously under‐documented bones should be established and tested by the forensic anthropological community. This study tests the accuracy of Wescott’s (J Forensic Sci 2000;45(2)) method for determining sex from the second cervical vertebra. Specimens were drawn from the donated skeletal collection curated at the Hamilton County Forensic Center (n = 57) and the William M. Bass Donated Skeletal Collection (n = 243). Both intra‐ and inter‐observer error rates were low and accurate classifications ranged from 78% (females‐Function 1) to 90.6% (males‐Function 5). Of the five functions, Function 4 achieved the highest overall accuracy, with 260 individuals (86.7%) falling into the correct category. Overall, this method is an effective classificatory tool for sex estimation.  相似文献   
384.
评估锁骨胸骨端骨龄对于推断青少年是否已满18周岁法定责任年龄具有实用价值,传统的研究方法主要基于X线检查,但由于锁骨胸骨端与相邻的肺、支气管、胸骨、肋骨及胸椎横突等解剖结构相互重叠,通过X线观察锁骨胸骨端骨骺发育时,较易出现假阴性或假阳性的阅片结果,直接影响骨龄鉴定意见的科学性与准确性。近年来,国内外已有学者运用薄层CT扫描技术评估锁骨胸骨端骨龄,并通过联合CT二维、三维图像重组技术,使骨骺形状、大小及位置得以清晰显示,提高了结果的准确性。据此,本文综述了国内外关于薄层CT扫描技术在锁骨胸骨端骨龄评估中的应用及研究进展,分析薄层CT扫描技术运用于锁骨胸骨端骨龄研究的优势以及价值所在。  相似文献   
385.
牙齿是人体最坚硬的器官,不易因外界理化因素的变化而降解、变形,利用牙齿推断年龄已广泛应用于法医学。通过牙齿影像推断年龄是过去使用最普遍的方法之一,而锥形束计算机体层摄影术(cone beam computed tomography,CBCT)技术的出现为牙齿三维影像的获取提供了新途径,具有照射剂量低、扫描时间短、成像精度高及费用低等优点。本文综述了CBCT技术的研究进展及其在牙龄推断中的应用。  相似文献   
386.
Second to fourth digit ratios (2D:4D) are sexually dimorphic in human hands and established by the 13th gestational week. Application of 2D:4D for determining sex in living individuals by Kanchan et al. (Forensic Sci Int, 181, 2008, 53.e1) produced classification rates of 80% for males and 74–78% for females. Few studies have explored the use of 2D:4D for sexing skeletal remains. We test estimated finger lengths, phalanx lengths, and 2D:4D derived from hand bones for determining sex. Maximum phalanx length was collected using a mini‐osteometric board from 451 individuals of known age, sex, and ancestry in four skeletal collections. Logistic regression of 2nd and 4th digit finger and phalanx lengths produced classification rates greater than 80%. Digit ratios, however, failed to reach classification rates greater than 59%. Our results support those of Voracek (Forensic Sci Int, 185, 2009, e29) and suggest that 2D:4D may be population‐specific and thus inappropriate for universal application as a means of determining sex.  相似文献   
387.
股东资格是出资人行使股东权利、承担股东义务的基础。在有限责任公司中的隐名股东资格认定问题上,“双重标准、内外有别”应当成为处理隐名股东资格纠纷遵循的基本原则。具体而言,对于公司内部关系.隐名股东和显名股东之间对股东资格及股权权益的分配有约定的依约定,无约定或约定不明的,原则上依据股东资格认定的实质要件来判断:对于公司外部关系,依据股东资格认定的形式要件来判断,即原则上确认显名股东的股东资格,并以工商登记的效力为最高标准。  相似文献   
388.
Abstract: Dr. Hawley Crippen was accused and convicted of murdering his wife in London in 1910. Key to the conviction was microscopic analysis of remains found in the Crippen’s coal cellar, which were identified as Cora Crippen based on a scar she was said to have. Dr. Crippen was hanged, always proclaiming his innocence. In this study, genealogical research was used to locate maternal relatives of Cora Crippen, and their mitochondrial haplotypes were determined. Next, one of the pathology slides of the scar was obtained, DNA was isolated, and the haplotype was determined. That process was then repeated. Finally, both DNA isolates were assayed for repetitive elements on autosomes and repetitive elements specific to the Y chromosome. Based on the genealogical and mitochondrial DNA research, the tissue on the pathology slide used to convict Dr. Crippen was not that of Cora Crippen. Moreover, that tissue was male in origin.  相似文献   
389.
Abstract: The few available studies on fetal age estimation concern very small samples, and statistical analysis is sometimes inadequate. In this survey, we used germs of deciduous teeth to estimate fetal age. Forty‐nine fetuses and 40 mandibles were scanned, and observations and measurements were made on DentaScan images. After checking their repeatability and reproducibility (analysis of variance), we defined thresholds using Fisher’s linear discriminant analysis to calculate the probability that a fetus was over or below a predefined age threshold. The forensic threshold which is of particular interest in France is 22 weeks amenorrhea. Relationships between fetal age and deciduous germ measurements were then sought by multiple linear regression. The thresholds gave very good results: 91.84% of good probability for the threshold of 22 weeks amenorrhea with no chance of error. The most precise age evaluation obtained nevertheless gave a range of ±4.6 weeks amenorrhea, so greater accuracy is still needed.  相似文献   
390.
目的检测皮肤切创愈合过程中α7nAChR的表达及其时间规律性变化。方法建立小鼠皮肤切创模型,应用免疫组织化学技术及Western blot方法检测切创后不同时间段皮肤中α7nAChR的表达。结果免疫组织化学结果显示,对照组α7nAChR表达于表皮、毛囊、皮脂腺、血管内皮及真皮中少数的成纤维细胞;伤后6~12h切创皮肤损伤区及周边区可见少量多核粒细胞和单核细胞表达α7nAChR,1~3d以单核细胞阳性表达为主,5~14d以成纤维细胞为主。α7nAChR阳性细胞率于伤后1d开始升高,伤后7d达最高峰,随后逐渐下降。经Western blot检测显示,对照组及各实验组均有α7nAChR阳性条带,其中伤后7d为α7nAChR表达高峰。结论α7nAChR在小鼠皮肤切创愈合过程中呈现一定的时序性变化。  相似文献   
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