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In the field of forensic medicine, diagnosis of sudden cardiac death is limited by subjective factors and manual measurement methods, so some parameters may have estimation deviation or measurement deviation. As postmortem CT imaging plays a more and more important role in the appraisal of cause of death and cardiopathology research, the application of deep learning such as artificial intelligence technology to analyze vast amounts of cardiac imaging data has provided a possibility for forensic identification and scientific research workers to conduct precise diagnosis and quantitative analysis of cardiac diseases. This article summarizes the main researches on deep learning in the field of cardiac imaging in recent years, and proposes a feasible development direction for the application of deep learning in the virtual anatomy of sudden cardiac death at present.基于深度学习的心脏影像学数据测量及其在心脏性猝死诊断中的应用.在法医学领域，心脏性猝死的诊断受主观因素和人工测量方法的限制，使某些参数可能存在估计偏差或测量偏差。随着死后断层影像在死因鉴定和心脏病理学研究中发挥越来越重要的作用，应用深度学习等人工智能技术对海量的心脏影像学数据进行分析，为法医学鉴定和科研工作者对心脏疾病进行精细诊断和定量分析提供了可能。本文对近几年深度学习在心脏影像学领域的主要研究进行综述，为目前深度学习在心脏性猝死虚拟解剖中的应用提出可行的发展方向。.法医病理学；医学影像技术学；心脏性猝死；虚拟解剖；深度学习；心血管系统；综述.

Objective To discuss the methods and strategies to identify the causes of dependents' deaths, as well as provide the experiences that can be used for reference and scientific basis for the forensic identification of the potentially growing deaths of the same kind in the future. Methods The 13 cases concerning death of dependents accepted by Sun Yat-sen University Forensic Center were collected, and the basic information of the dependents were statistically described. The nutritional status, environmental condition and medical care condition were evaluated according to dietary energy, living space, environment and medical treatment condition. Results Among the 13 dependents, there were 11 males and 2 females, with the oldest 74 and the youngest 9 and dwelling time was from 0.4 to 5.6 years. Forensic pathological examination showed that 13 dependents had infectious diseases and 11 were severely dystrophic. There were no fatal mechanical injuries or poisoning in dependents. Molecular pathological screening of 4 cases revealed no pathogenic variants of sudden death susceptible genes. The poor status of the diet, nutrition, living environment and medical care of these dependents were discovered. The direct cause of death of all 13 dependents was identified to be disease. The lack of nutrition, poor living environment and lack of medical care were thought to play a dominant role in causing the deaths of 12 dependants. Conclusion The death identification should follow the judicial procedure. In identification of the causes of death and analysis of the proportion of the affecting factors resulting in death, all factors, including nutrition,environment, medical care, injury and diseases, need to be considered.被看护人员死亡原因鉴定策略.目的 探讨被看护人员死亡原因鉴定的方法和策略，为潜在增长的此类死亡事件的法医学鉴定提供可借鉴的实践经验和科学依据。 方法 收集中山大学法医鉴定中心受理的13例被看护人员死亡案件，对被看护人员的基本信息进行统计描述。以膳食能量、居住面积及环境、就医情况分别评估营养状况、环境条件、医护条件。 结果 13例被看护人员中，有11例男性，2例女性；年龄最长者74岁，最小者9岁；在福利机构居住时间最长者5.6年，最短者0.4年。法医病理学检验发现13例均患有感染性疾病，11例存在严重营养不良。所有被看护人员均未检见致命性机械性损伤及中毒情况。4例经分子病理学检测未发现猝死易感基因的致病性突变。被看护人员饮食营养、生活环境、医疗护理状况存在不足。13例被看护人员的直接死亡原因均被鉴定为疾病，营养、居住、医护等条件不足在12例被看护人员的死亡后果参与程度中占主要因素。 结论 被看护人员死亡鉴定应遵照司法程序开展，其死亡原因鉴定及死亡后果参与程度分析须综合考虑营养、环境、医疗护理、损伤及疾病等因素。.法医病理学；被看护人员；虐待；死亡原因.

Objective Quantitative analysis and comparison of the expression of ribonucleic acid （RNA） from frozen organs and formaldehyde-fixed and paraffin-embedded （FFPE） tissues. Methods Frozen specimens of human brain, myocardium and liver tissues as well as FFPE samples at different postmortem intervals were collected and mass concentration of RNA was extracted and detected. Reverse transcription-quantitative polymerase chain reaction （RT-qPCR） technology was used to analyze the amplification efficiency and relative expression of each RNA marker. Results The mass concentration and integrity of RNA extracted from FFPE samples were relatively low compared with frozen specimens. The amplification efficiency of RNA markers was related with RNA species and the length of amplification products. Among them, glyceraldehyde-3-phosphate dehydrogenase （GAPDH） and β-actin （ACTB） with relatively long amplification products failed to achieve optimal amplification efficiency, whereas 5S ribosomal RNA （5S rRNA） achieved ideal amplification efficiency and showed quite stable expression across various tissues, therefore it was chosen as internal reference marker. The expression quantity of GAPDH and ACTB in frozen specimens with longer postmortem intervals and in FFPE samples with relatively long amplification products was decreased. The expressions of tissue-specific microRNAs （miRNAs）, GAPDH and ACTB with relatively short amplification products had consistency in the same tissues and FFPE samples. Conclusion Through standardizing the RT-qPCR experiment, selecting the appropriate RNA marker and designing primers of appropriate product length, RNA expression levels of FFPE samples can be accurately quantified.冻存器官和甲醛固定石蜡包埋组织中RNA的定量表达.目的 定量分析并对比冻存器官和甲醛固定石蜡包埋（formaldehyde-fixed and paraffin-embedded，FFPE）组织中核糖核酸（ribonucleic acid，RNA）的表达情况。 方法 选取不同死亡时间人体脑、心肌和肝组织的冻存及FFPE样本，提取并检测RNA质量浓度，运用实时荧光定量反转录聚合酶链反应（reverse transcription-quantitative polymerase chain reaction，RT-qPCR）技术分析各RNA指标的扩增效率及相对表达量。 结果 与冻存样本相比，FFPE样本中所提取RNA的质量浓度和完整性相对较低。各RNA指标扩增效率与RNA种类及扩增产物长度有关，其中扩增产物较长的甘油醛-3-磷酸脱氢酶（glyceraldehyde-3-phosphate dehydrogenase，GAPDH）及β-肌动蛋白（β-actin，ACTB）扩增效率不理想，而5S核糖体RNA（5S ribosomal RNA，5S rRNA）扩增效率理想且在各组织中表达稳定，故选为内参指标。较长死亡时间的冻存样本及FFPE样本中扩增产物较长的GAPDH及ACTB表达量下降，而组织特异性微小RNA（microRNA，miRNA）以及扩增产物较短的GAPDH和ACTB在同一组织冻存和FFPE样本中表达具有一致性。 结论 通过标准化RT-qPCR实验，选取合适的RNA指标及设计合适产物长度的引物，能够准确定量FFPE样本中RNA的表达水平。.法医病理学；核糖核酸；石蜡包埋；冷冻保存；反转录聚合酶链反应；核糖核酸完整性指数.

To explore the correlation between the expression levels of several RNA markers in human brain tissue and early postmortem interval （PMI）.Twelve individuals with known PMI （range from 4.3 to 22.5 h） were selected and total RNA was extracted from brain tissue. Eight commonly used RNA markers were chosen including5S rRNA, miRNA-9 and miRNA-125b showed quite stable expression and their expression levels had no relation with age, gender and cause of death. The error rate of estimated PMI using5S rRNA, miRNA-9 and miRNA-125b are suitable as internal reference markers of human brain tissue owing to their stable expression in early PMI. The expression level of

To explore the correlation between early postmortem interval （PMI） and eight RNA markers of rat's brain at different temperatures.Total 222 SD rats were randomly divided into control group （PMI=0 h） and four experimental groups. And the rats in the experimental groups were sacrificed by cervical dislocation and respectively kept at 5 ℃, 15 ℃, 25 ℃ and 35 ℃ in a controlled environment chamber. The RNA was extracted from brain tissues, which was taken at 9 time points from 1 h to 24 h postmortem. The expression levels of eight markers, β-actin, GAPDH, RPS29, 18S rRNA, 5S rRNA, U6 snRNA, miRNA-9 and miRNA-125b, were detected using real-time fluorescent quantitative PCR, respectively. Proper internal reference was selected by geNorm software. Regression analysis of normalized RNA markers was performed by SPSS software. Mathematical model for PMI estimation was established using R software. Another 6 SD rats with known PMI were used to verify the mathematical model.5S rRNA, miR-9 and miR-125b were suitable as internal reference markers for their stable expression. Both β-actin and GAPDH had well time-dependent degradation patterns and degraded continually with prolongation of PMI in 24 h postmortem. The mathematical model of the variation of ΔCt values with PMI and temperature was set up by R software and the model could be used for PMI estimation. The average error rates of model validation using β-actin and GAPDH were 14.1% and 22.2%, respectively.The expression levels of β-actin and GAPDH are well correlated with PMI and environmental temperature. The mathematical model established in present study can provide references for estimating early PMI under various temperature conditions.

Time expression of SJA tissue receptors surrounding wounded skin of 40 rats was studied by affinity histochemical method. The results were compared to that by EGFR immunohistochemical method and c-myc situ hydridization method. It was observed that SJA receptors began to decrease after the skin was injured and reached the lowest quantities in 15 minutes. After that, they began to increase and reached the highest quantities in 2 hours. It needs to be further studied whether there is the correlation between SJA receptors and EGFR has the function of repairing wounded skin.

To explore expression of the glycoprotein in early myocardial ischemic.The glycoprotein changes occurred at the early acute cardiac ischemic area induced experimentally by ligation of left coronary artery of 32 SD rats. 6 lectins were measured by means of immunohistochemical methods.Positive staining of PNA could be observed in ischemic area at 5 min after ischemia, and the positive area increased with the prolongation of ischemic period. It became the strongest for 2 h and then decreased.This experiment proved that myocardial cell membrane in ischemia expressed D-galactose. This may be of some value in forensic medicine practice.