利用猪胸主动脉生物力学性能时序性变化推断死亡时间

目的观察分析家猪尸体胸主动脉生物力学性状指标的变化规律,探讨其在死亡时间(PMI)推断中的应用价值。方法采集180根家猪的主动脉,在恒定温度、湿度下,于2～230h之间每间隔12h设置1个取检材时间点组;各组主动脉检材用电子万能材料试验机拉伸检测极限载荷、极限载荷变形、平均力、应力、应变,宽度和厚度等生物力学参数指标;应用多元逐步回归方法进行统计学分析。结果家猪死后230h内,随PMI延长,胸主动脉大体观呈自溶腐败性变色、瘫软、液化趋势。生物力学参数指标中,极限载荷、平均力和应力呈随PMI延长呈明显下降趋势,PMI间隔24h组间比较差异性均有统计学意义(P<0.05),校正决定系数分别为0.923、0.806、0.867,估计标准误差分别为±18.39h、±29.88h、±24.58h,PMI间隔24h组间比较差异性均有统计学意义(P<0.05),其它指标与PMI之间相关性不显著均P>0.05。结论死后230h内家猪胸主动脉的极限载荷、平均力和应力的死后时序性变化,与PMI呈明显的负相关性,可用于PMI推断,其中极限载荷效果最佳。     

反相高效液相色谱法检测生物胺的法医学应用初探

目的采用反相高效液相色谱法(RP-HPLC)检测大鼠肌肉组织中7种生物胺,并探讨其在法医学中的应用价值。方法以丹磺酰氯为衍生剂,通过ZORBAX Rx-C18反相色谱柱分离,以乙腈-水作流动相梯度洗脱,流速为1.0mL/min,柱温为20℃,DAD检测器,对色胺、腐胺、尸胺、组胺、酪胺、亚精胺、精胺7种生物胺进行检测。结果 7种生物胺得到良好分离,在0.5～100.0μg/mL的范围内线性良好,相关系数均>0.99,检出限在0.14～0.50μg/mL之间;对大鼠肌肉样本的添加回收率在83.8%～100.6%之间,相对标准偏差均<11%。结论采用RP-HPLC法检测生物胺,方法简便、快速、灵敏,能够满足尸体组织中生物胺检测的需要。     

256例命案尸体死亡时间推断的回顾性分析

目的探讨降低死亡时间推断误差的方法。方法收集常州市和南京市2003年1月一2013年1月256例已破命案．采用传统方法进行死亡时间推断,与破案后获得的实际死亡时间进行比较,并根据死亡时间进行分组,计算死亡时间推断准确率,分析判断错误原因。结果早期尸体死亡时间（≤12h和13～24h）推断准确率分别为90％、89％,晚期尸体死亡时间（1—7d、1～2周、3～4周、1～6个月、7～12个月和1～5年）的推断准确率随时间的延长下降,分别为79％、76％、83％、79％、60％和50％。推断方法不当、水中尸体、极端温度、客观依据不足、抛尸以及变动或破坏现场是影响死亡时间推断准确率的常见因素。结论综合参考多项指标可降低死亡时间推断的误差。     

尿素氮、肌酐和尿酸死后生化学检测的法医学应用

死后生化学是法医鉴定中重要的检查手段。研究表明含氮化合物中尿素氮、肌酐、尿酸是临床上常用的生化学检测指标,其在法医死后生化学检测中也有重要的价值。本文就体内上述三者的特征及其在法医学中的研究及应用加以综述,以期为法医死后生化学分析提供参考。     

Disentangling legislative duration in coalitional presidential systems

ABSTRACT

The speed and actions that bills face in legislatures vary immensely, but we do not have a comprehensive framework to analyse legislative durations. Moreover, the absence of data detailing legislative activities and durations in distinct stages of legislative processes hinders analysis. This article presents a framework for analysing legislative delay in coalitional presidential systems and examines unique data on durations, attributes, and parliamentary activities in legislative processes at the level of individual proposals. The empirical analysis investigates executive proposals considered by the Brazilian Congress and seeks to disentangle when duration means legislative activism, when it is due to political conflict, and when it only represents inertia. Our analysis indicates substantial activities in both content-influencing legislative activism and politically motivated obstructionism. Hence, political conflict is as important a source as policy disagreement in accounting for legislative delay. By examining a hitherto untapped area with rich data, this study opens up new venues for rigorous analyses of legislative durations and gridlock.     

土地承包关系长久稳定的制度建构

土地承包关系之所以始终不稳定,现行土地承包经营权存在诸多制度性缺陷,是重要原因之一。中共十七届三中全会所作"现有土地承包关系要保持稳定并长久不变"的决定,是适应城乡发展一体化新格局、立足农业是安天下、稳民心的战略产业而作出的重大决策。将此项政策转化为法律时,可从以下方面重构现行土地承包经营制度:消除对土地承包的行政干预;废除强制收回承包地的规定;规定土地承包经营权自登记时设立;确立土地承包经营权期满自动续期制度;承认土地承包经营权的可继承性;完善土地承包经营权转让、抵押制度。     

DNA降解与腐败尸体死亡时间的相关性

目的探讨骨髓细胞核DNA含量变化与腐败尸体死亡时间的关系。方法应用DNA高度特异性染色方法Feulgen改良法结合计算机图像分析技术对死后不同时间(0～14d)胸骨骨髓细胞核DNA含量变化进行分析。结果胸骨骨髓细胞核DNA含量随死亡时间延长呈缓慢而规律下降,直至死后两周仍未完全降解。结论死后DNA降解速率与死亡时间呈线性关系,测定死后骨髓细胞核DNA含量可望成为腐败尸体死亡时间推断的新方法。     

利用肌原纤维小片化指数推断死亡时间

目的研究死后机体骨骼肌肌原纤维小片化指数(MFI)与死亡时间之间的关系。方法双缩脲法测定室温下不同死后时间家兔骨骼肌全蛋白浓度,分光光度法测定540nm处0.5mg/mL蛋白浓度下的骨骼肌肌原纤维小片化指数。结果在死后早期,肌原纤维小片化指数随着时间延长逐步增高。结论肌原纤维小片化指数可用于早期死亡时间的推断。     

Zur ultrastruktur vitaler,postmortaler und autolysierter gerinnsel

Investigations on animal experimental and human tissue material (skin, musculature, liver) with the scanning electron microscope are reported. These studies were carried out to clarify open questions on extravascular fibrin structures after blunt and sharp traumatization of vital and postmortem nature. The network formation which was already characterized earlier as typically vital and the irregular structure of postmortem coagula could be demonstrated even with modification of the traumatization, especially in tissue hematomas. Experimental investigations on autolysis revealed an exceedingly good preservation of the structure of vital coagulum material with massive damage and granular decomposition of fibrin fiber structures produced postmortem. The structural differences in the mode of interlinking of the fibrin was shown up especially clearly by the autolysis, which suggests an application as preparation technique for the question specified.Special modifications of the preparation technique (fixation according to Karnovsky, critical-point drying) did not provide such substantial advantages for routine investigations that they might be generally recommended.Sources of artefacts and possibilities of misinterpretation of findings as well as more advanced techniques are discussed.