小鼠皮肤切创愈合过程中iNOS和eNOS表达的免疫组织化学研究

目的观察小鼠皮肤切创愈合过程中,iNOS和eNOS在损伤区及损伤周边区内的表达及其变化规律。方法小鼠背部制作全层切创,应用免疫组织化学技术观察伤后切创组织中iNOS和eNOS的表达,并和无切创的小鼠作为对照。结果损伤区及损伤周边区细胞,伤后3h的损伤皮肤组织中可见少量的多型核细胞表达iNOS和eNOS,伤后6～24h,大部分浸润的中性粒细胞和单核细胞为iNOS和eNOS阳性。随着时间的延长,iNOS和eNOS阳性细胞以单核细胞和成纤维细胞为主。伤后3hiNOS的阳性细胞比率较低,6h～1d持续性增加并于1d达到最高峰,3～7d维持在一个相对稳定的水平直至伤后10d再次达高峰,10～14d开始下降。eNOS的阳性细胞率在伤后1～3h表达较低,6h～3d持续性增高,并在3d达到最高峰,在其后的5d内保持稳定表达,之后开始下降。而且损伤区及损伤周边区、特别是肉芽组织内的新生血管可见iNOS和eNOS不同强度的表达。结论小鼠皮肤切创愈合过程中,iNOS和eNOS在损伤周边区内多型核细胞、单核细胞和成纤维细胞中表达,其时序性变化可望用于皮肤损伤时间的推断。     

Comparing the Validity of Prospective,Retrospective, and Official Onset for Different Offending Categories

Using data from the Cambridge Study in Delinquent Development, a prospective longitudinal study of 411 London males, the main aim of this research is to compare the age of onset of six types of offenses according to different methods of measurement – prospective self-reports, retrospective self-reports, and official records – and also to explore self-reported and official onset sequences. Results showed that ages of onset reported in retrospective accounts generally tended to be higher than those reported prospectively. Agreement rates between prospective and retrospective accounts were lowest for minor forms of offending, and highest for more serious offenses such as theft of vehicles. Males with heavy substance use habits were less likely to report the same age of onset retrospectively compared with prospectively. Denial rates were substantial in all comparisons, particularly for minor forms of offending. Comparisons between self-reported and official measures of onset revealed that there was a greater degree of agreement between the two measures for serious offenses. Whereas self-reported onset sequences suggested that minor crimes were committed before more serious offenses, official onset sequences suggested the reverse. The findings show that retrospective reports are not suitable to address research questions requiring detailed information (i.e., most criminal career parameters: age of onset, frequency, age of termination, etc.), for studying minor forms of offending, and for samples of individuals with serious substance use habits. Furthermore, official measures of offending can also produce misleading results, particularly when studying minor forms of offending.     

小鼠皮肤切创愈合过程中磷酸化 p38MAPK 表达及其与时间的相关性

目的探讨小鼠皮肤切创愈合过程中损伤区磷酸化p38MAPK(p-p38MAPK)的表达情况,以及不同损伤时间p-p38MAPK的变化规律。方法应用免疫组织化学和Westernblot的方法检测33例小鼠皮肤切创后各个时间段p-p38MAPK表达情况。结果正常组织中有少量的p-p38MAPK表达。伤后3～12h损伤区p-p38MAPK主要表达于中性粒细胞中,1～5dp-p38MAPK阳性表达主要为单核细胞和成纤维细胞。7～14dp-p38MAPK阳性表达主要以成纤维细胞为主。阳性细胞率3～12h逐渐升高,1d有所下降,3、5d阳性细胞率保持在高水平,7～14d阳性细胞率逐渐降低。Westernblot显示各个时间段均有p-p38MAPK的表达。其中12h和3d为2个p-p38MAPK含量的高峰。结论在小鼠切创愈合过程中p-p38MAPK在损伤区对诱导中性粒细胞、单核细胞和成纤维细胞的凋亡起重要的作用,同时p-p38MAPK的规律性表达可用于损伤时间的推断。     

14岁青少年手腕骨发育的研究I．男生骨龄标准的制定

目的研究我国当前青少年骨发育状况,制订专用于法医学推断男性刑事责任年龄14岁的骨龄标准。方法以湖南冷水江地区青少年为对象,按照纳入标准,选取14岁±3个月的健康男性中学生103名,拍摄其左手腕部后前位X线片。选择手腕骨15个部位,按照统一标准进行观察、测量,采用最大百分比法确定发育等级标准,建立骨龄评估方法,以单盲法进行验证。结果除第一掌骨、近节第四指骨骨骺发育等级为部分闭合外,其他均为未闭合;对于第四、五掌骨和近三指骨,不足14岁组以未闭合为主,已满14岁组以部分闭合为主。各个观察部位骨骺横径宽于干骺横径。30例的验证结果准确率为80.0%。结论根据发育等级特征及测量学方法建立骨龄评估标准可行,可望得到推广。本文以刑事责任年龄14周岁为对象,制订法医学专业骨龄推断标准,并引入测量学方法,辅助推断年龄。     

纸张检验综述

纸张检验是文件检验鉴定技术的重要组成部分之一。文章对有关纸张种类鉴别和纸张相对形成时间检验的文献进行了综述,介绍了用于纸张种类和形成时间检验的无损和有损方法,对各种方法的适用性进行了归纳总结。     

Using anisotropic diffusion for efficient extraction of sensor noise in camera identification

Each digital camera has an intrinsic fingerprint that is unique to each camera. This device fingerprint can be extracted from an image and can be compared with a reference device fingerprint to determine the device origin. The complexity of the filters proposed to accomplish this is increasing. In this note, we use a relatively simple algorithm to extract the sensor noise from images. It has the advantages of being easy to implement and parallelize, and working faster than the wavelet filter that is common for this application. In addition, we compare the performance with a simple median filter and assess whether a previously proposed fingerprint enhancement technique improves results. Experiments are performed on approximately 7500 images originating from 69 cameras, and the results are compared with this often used wavelet filter. Despite the simplicity of the proposed method, the performance exceeds the common wavelet filter and reduces the time needed for the extraction.     

胸骨形态变化与年龄关系的研究进展

胸骨在发育和退化的过程中,随年龄增长发生着规律性形态改变.国内外学者对胸骨形态变化与年龄的关系做了大量研究,积累了一些宝贵资料,这些成果为研究胸骨三维重建影像的形态变化奠定了基础.三维重组技术的引入,有望引起利用胸骨推断活体年龄方法的突破性发展.本文对相关研究进展进行综述.     

重型颅脑损伤数字计算ERP特征及与智商的相关性

目的 根据ERP理论和韦氏智力量表内容建立数字计算ERP范式,探讨正常人与重型颅脑损伤患者数字计算ERP特征及与智商的相关性.方法 采用Neuroscan-ERP仪和韦氏智力量表对29名重型颅脑损伤患者(外伤组)和46名正常人(对照组)进行ERP及智商检测,比较引出的ERP成分特征及与智商的相关性.结果 数字计算范式的题目、正确、错误答案3类刺激引出的ERP波形包括外源性成分N1c、P2c及内源性成分N2c和P3c;对照组引出的N1c和P2c波幅和潜伏期相近,但N2c和P3c有明显差异,其中正确答案的P3c波幅最高,错误答案的P3c潜伏期最长;外伤组引出的各ERP成分波幅降低、潜伏期延长,N2c和P3c具有显著性差异(P＜0.05);对照组错误答案引出的P3c潜伏期与言语智商和总智商呈中度负相关,高于题目和正确答案;外伤组P3c潜伏期与言语智商、操作智商和总智商的相关系数分别为-0.64、-0.46和-0.60(P ＜0.05),明显高于对照组.结论 数字计算ERP范式可引出特征性ERP波形,其P3c潜伏期与智商有一定相关性,可作为评价重型颅脑损伤后数学能力损害程度的参考指标.     

根据骨骺愈合程度推断青少年年龄

骨骺愈合程度作为推断青少年活体年龄的重要手段之一,在相关鉴定中得到了广泛的应用.随着技术发展,国内外众多学者利用骨骺愈合程度推断年龄的研究取得了很多成果,本文针对根据骨骺愈合程度推断年龄的方法的产生、发展、研究成果以及有待解决的问题等进行综述,以期为相关研究和实践提供参考.     

QQ取证及其司法鉴定方法研究

简要介绍QQ取证及其司法鉴定研究的发展现状。分析QQ消息传输协议、数据库文件结构、Msg2.0.db文件的加密机制,重点研究QQ聊天记录及其他证据信息获取的思路和方法。在结合QQ取证鉴定案例的基础上,提出将手机与QQ进行融合取证的新思路,并对QQ取证及其司法鉴定的发展方向进行展望。