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171.
The study evaluated secular trends in dental development during a period of 30 years, correlation between dental and chronological age in Istria and the littoral region of Croatia. The sample consisted of 1000 panoramic radiographs of children, aged 6–16 years (mean 10.0 ± 1.8), taken in the period 1977–1979 (N = 500; 243 females) and 2007–2009 (N = 500; 299 females). Dental age was assessed according to Demirjian's method. Correlation between chronological and dental age was linear, positive, high, and statistically significant in both periods and genders, ranging from 0.73 to 0.86. Dental age was underestimated when compared to chronological age by 1 year on average, more 30 years ago (?1.35 ± 1.17) than today (?0.63 ± 1.09), less for girls (?0.80 ± 1.22) than boys (?1.21 ± 1.10). A statistically significant positive secular trend in acceleration of dental development was present of 0.72 years during the 30‐year period and was more significant in girls than boys (0.83‐ and 0.51‐year acceleration).  相似文献   
172.
Studies of public support for capital punishment have consistently observed a strong and enduring gender gap in the level of death penalty support, with males consistently more inclined than females to support capital punishment. This unexplained relationship has endured over time and space as well as across a myriad of research designs. The present study uses attribution theory in a factorial survey design to account for this relationship. Analyses of data obtained from jurors provide mixed support for attribution theory yet fails to bridge the gender gap in death penalty support. The implications of these findings as they relate to gender, socialization, and attributions are discussed.  相似文献   
173.
Because arrest rates are especially high for teenagers and young adults, criminologists have long contended that age structure changes affect crime trends. In recent years, however, this belief has been drawn into question because crime has not declined even though high-crime age groups have shrunk. We argue that the age/crime relationship is probably exaggerated because the high arrest rates for younger persons are due partly to their lesser ability to escape arrest, younger persons commit more group crime, and the age structure of victims should be taken into account. We then review 90 studies that regress crime rates on age structure; only a small minority consistently finds significant relationships. Because of methodological problems in this research, one cannot conclude that the age/crime relationship does not exist, but the weight of evidence shows that forecasts based on demographic trends are not likely to be helpful.  相似文献   
174.
We examined the utility of CT scans in the evaluation of degree of ectocranial suture closure. Five cranial points (left and right midcoronal positions, left and right midlambdoidal positions, and the lambda) were evaluated in 231 CT scans using a three‐point scoring system (open, partial closed, and closed). The slice increment and thickness varied between three groups of the scans. The results showed a good correlation between degree of suture closure and increasing age in each group. Young individuals (<40 years) and old individuals (>60 years) could be clearly distinguished from the middle‐aged individuals. ANOVA test revealed no difference between two groups of scans and between left and right sides (> 0.05). Interobserver agreement was good, especially considering the score by sides. The results of this study create the base for developing a robust and simple method to estimate the age at death using CT scans.  相似文献   
175.
Abstract:  This study evaluates a new method of fetal age estimation based on orbital measurement and including the potential trisomy 21 of the fetus. Six orbital and one facial CT-scan measurements were taken on 71 fetuses ranging from 14 to 41 weeks of gestational age. Forty-eight fetuses were "normal" and 23 fetuses presented the Down syndrome (trisomy 21). The anatomy/imagery correspondence was evaluated comparing our results to those obtained by direct bone measurements on the same fetuses and revealed no significant differences between the two kinds of measurements. Moreover, a multiple linear stepwise regression was realized to estimate fetal age and showed that the "trisomy 21 parameter" is not conserved in the final determination model. Therefore, we conclude that the good radio-anatomical correspondence offers an interesting alternative to direct bone measurement (necessitating dissections) and allows a reliable fetal age determination, whatever is the trisomy 21 condition of the fetus.  相似文献   
176.
目的观察大潮气量机械通气致兔急性肺损伤(acutelung injury,ALI)后,肺组织中血管内皮生长因子(VEGF)的动态变化,探讨其在损伤时间推断中应用的价值。方法57只雄性新西兰大白兔随机分为正常组(3只)、对照组(27只)和实验组(27只)。机械通气(V_T 60mL/kg)致AL后于0,1,3,6,12,18,24,36,48h各处死动物3只。取肺组织,测量右上肺组织湿干重比(W/D),肺组织进行HE及免疫组织化学染色并进行图像定量分析,观察VEGF变化规律。结果正常组VEGF有低水平表达;大潮气量机械通气1min后至肺损伤后12h,实验组VEGF表达水平与正常组无明显差异(P>0.05);12~48h随损伤时间的延长VEGF表达水平持续上升,48h仍处于较高水平,其间各时间点VEGF表达水平与正常组比较均有显著性差异(P<0.05)。结论大潮气量机械通气致兔ALI 2d内,VEGF在肺组织炎症发生、发展和愈合修复过程中存在时间相关性,对法医病理推断呼吸机所致的ALI时间具有参考价值。  相似文献   
177.
死亡大鼠看家基因mRNA时序性降解的组织差异性研究   总被引:3,自引:2,他引:1  
目的研究死亡大鼠看家基因mRNA时序性降解的组织差异性,评价其用于死亡时间推断的价值。方法SD大鼠20只分为死后0、1、3、5、7d共5组,脊椎脱臼法处死大鼠,提取大鼠心、肝、脾、肺、肾、脑组织,在相应时间段提取RNA,应用一步法RT-PCR技术检测各组织中看家基因GAPDHmRNA和β-actinmRNA的水平,Vilber凝胶图像分析系统测定扩增产物IOD值,SPSS10.0统计软件对数据进行方差分析。结果GAPDHmRNA、β—actinmRNA扩增产物相对灰度与积分光密度值随死后经过时间的延长而逐渐减小,且与死亡时间显著相关,大鼠脾脏和脑组织GAPDHmRNA和β-actinmRNA在死后5d内可检出,心脏和肾脏在死后3d内可检出,而肝脏和肺脏GAPDHmRNA和β-actin mRNA降解较快,仅在死后1d内可检出。结论脑组织和脾脏中mRNA稳定性较好,适用于PMI特别是晚期PMI的推断。除环境温度外,环境湿度也是死亡时间推断中的重要影响因素。  相似文献   
178.
目的探讨大鼠皮肤切创后E-选择素表达规律及法医学意义。方法健康SD大鼠90只,随机分成4组:正常对照组、活体切创组(30min~7d12个时间点)、死后切创组(30min~3h3个时间点)、死后稳定性组(-20%6h-7d9个时间点,25%6h~3d5个时间点)。在大鼠头部建立皮肤切创模型,按设定的时间点取皮肤检材,运用免疫组化和图像分析技术,检测血管内皮E-选择素的表达规律。结果在活体切创组中,伤后1hE-选择素在血管内皮细胞内即呈阳性表达,持续至伤后7d,且随时间变化呈规律性表达。在正常对照及死后切创组未见阳性表达。死后-20%稳定性组各时间点E-选择素表达与死后即刻比较无显著性差异(P〉0.05)。25%各时间点与死后即刻比较有显著性差异(P〈0.01)。结论E-选择素在创伤后血管内皮细胞内特异性的表达具有时序性规律,且低温条件下稳定性较好。  相似文献   
179.
RUS-CHN图谱骨龄评价法用于推侧青少年年龄   总被引:3,自引:1,他引:2  
目的探讨RUS-CHN(RC)图谱评价法用于13~18岁青少年年龄推侧的应用价值。方法4 424名(男2 272,女2 152)13~18岁正常城市汉族青少年,以简化RUS-CHN法建立手腕骨发育等级图谱。另以1 048名(男530,女518)13~18岁青少年为检验样本,比较不同方法骨龄与生活年龄的差异。结果RUS-CHN图谱法可仅评价桡骨、尺骨远端和第III指的4块掌指骨骺。检验样本中男14~17岁、女13~16岁年龄组,RC图谱法骨龄与生活年龄之间的差异均无统计学显著性(W ilcoxon符号秩和检验,P>0.05),对男18岁、女17岁组出现显著性差异的可能原因进行了讨论。结论RUS-CHN图谱法骨龄适用于男13~18岁、女13~17岁青少年的年龄推测。  相似文献   
180.
玻璃体液化学成分规律性改变与死亡时间推断的研究进展   总被引:1,自引:0,他引:1  
死亡时间(postmortem interval.PMI)的准确推断是法医尸体检验工作中的难题之一,PMI推断对刑事案件的侦察和审判具有重要的意义。人死亡后不同时间眼玻璃体液化学成分的规律性变化,如钾、镁、氨、尿素氮、肌酐和尿酸、次黄嘌呤、乳酸的含量逐渐升高,而钙、钠、酶类、葡萄糖、维生素C的含量逐渐降低,有助于比较准确地进行PMI推断。本文对其在法医学领域的研究进展进行综述。  相似文献   
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