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961.
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963.
Wen  Hanjie  Wu  Wei  Fan  Fei  Liao  Peixi  Chen  Hu  Zhang  Yi  Deng  Zhenhua  Lv  Weiqiang 《International journal of legal medicine》2022,136(4):1067-1074

Human identification plays a significant role in the investigations of disasters and criminal cases. Human identification could be achieved quickly and efficiently via 3D sphenoid sinus models by customized convolutional neural networks. In this retrospective study, a deep learning neural network was proposed to achieve human identification of 1475 noncontrast thin-slice CT scans. A total of 732 patients were retrieved and studied (82% for model training and 18% for testing). By establishing an individual recognition framework, the anonymous sphenoid sinus model was matched and cross-tested, and the performance of the framework also was evaluated on the test set using the recognition rate, ROC curve and identification speed. Finally, manual matching was performed based on the framework results in the test set. Out of a total of 732 subjects (mean age 46.45 years ± 14.92 (SD); 349 women), 600 subjects were trained, and 132 subjects were tested. The present automatic human identification has achieved Rank 1 and Rank 5 accuracy values of 93.94% and 99.24%, respectively, in the test set. In addition, all the identifications were completed within 55 s, which manifested the inference speed of the test set. We used the comparison results of the MVSS-Net to exclude sphenoid sinus models with low similarity and carried out traditional visual comparisons of the CT anatomical aspects of the sphenoid sinus of 132 individuals with an accuracy of 100%. The customized deep learning framework achieves reliable and fast human identification based on a 3D sphenoid sinus and can assist forensic radiologists in human identification accuracy.

  相似文献   
964.
Fan  Haoliang  Wang  Lingxiang  Liu  Changhui  Lu  Xiaoyu  Xu  Xuding  Ru  Kai  Qiu  Pingming  Liu  Chao  Wen  Shao-Qing 《International journal of legal medicine》2022,136(2):447-464
International Journal of Legal Medicine - Short tandem repeats (STRs) are the preferred genetic markers in forensic DNA analysis, routinely measured by capillary electrophoresis (CE) method based...  相似文献   
965.
【摘要】 目的 探讨颈动脉狭窄患者颈动脉支架植入术(CAS)后产生低血压的危险因素。 方法 回顾性分析2018年1月至12月在首都医科大学宣武医院接受CAS治疗的137颈动脉狭窄患者临床资料。患者平均年龄66.3岁,手术侧颈动脉重度狭窄98例,中度狭窄39例。采用单因素和多因素logistic回归法分析评价持续性低血压的危险因素。结果 137例颈动脉狭窄患者CAS术后有51例(37.2%)发生低血压。单因素分析提示,与CAS术后低血压相关的因素,包括颈动脉狭窄部位在球部、术前存在未控制的高血压、钙通道阻滞剂(CCB)类药物史、尿素氮、术后24 h静脉液体入量。多因素logistic回归分析结果显示,有溃疡斑块、术前存在未控制高血压、术后24 h静脉液体入量,是CAS术后低血压的独立危险因素。结论 有溃疡斑块、术前高血压未控制、术后24 h液体入量较多患者,更易发生CAS术后低血压。  相似文献   
966.
胸痛评估的前瞻性多中心影像学研究(PROMISE)始于2010年,该研究分析症状稳定的疑似冠心病病人首选冠状动脉CT血管成像(CCTA)进行解剖学检查或首选无创性功能学检查,旨在探究病人临床结局的差异。PROMISE研究了CCTA、功能学检查及冠状动脉钙化积分和CT血流储备分数等无创性检查方法对疑似冠心病的稳定性胸痛病人的预后价值,并探讨了生物标志物、年龄、性别、代谢性疾病对稳定性胸痛病人的影响。此外,PROMISE开发并验证了风险分层模型和个体化选择检查方法的工具。PROMISE对CCTA和功能学检查的应用产生了很大的影响,为疑似冠心病病人无创检查方法的选择提供了重要循证依据。  相似文献   
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968.
OBJECTIVE: At present, there are few materials available for esophagus reconstruction anywhere in the world. The reported survival rate in animals during the perioperative period is comparatively low. The present study assessed the feasibility of using a biotype artificial esophagus in the reconstruction of a dog's esophagus. METHODS: In 30 mongrel dogs, a portion of the thoracic esophagus was resected and an 8 cm section of artificial esophagus was transplanted to reconstruct the organ. The survival rate, food intake and process of healing were observed. RESULTS: Of the 30 dogs, 28 survived the peri­operative period (93.3% survival). Two dogs (6.7%) developed an anastomotic fistula; 19 dogs survived for 1 year, a survival rate of 79.2% (19/24) with the remaining six dogs were killed according to the experimental protocol. Detachment of the artificial esophagus occurred on average 28.8 days after operation and the dogs suffered from varying degrees of dysphagia 23?45 days after operation. Gradual remission occurred after 4 months. The histological study revealed that the regenerated esophagus was composed of fibrous and connective tissues and the luminal surface was covered with squamous epithelium in 3?6 months. CONCLUSION: The transplanted artificial esophagus detached after the surrounding ‘regenerated esophagus’ had formed, and the squamous epithelium gradually covered the luminal surface. Continuous remodeling of the ‘regenerated esophagus’ gradually relieved the stenosis. Whether detachment of the implant and the postoperative stenosis can be solved is the key problem restricting the use of the biotype artificial esophagus in clinical practice.  相似文献   
969.
结核分枝杆菌分泌蛋白Ag85B-ESAT6的融合表达及纯化   总被引:6,自引:0,他引:6  
目的 融合表达结核分枝杆菌分泌蛋白Ag85B ESAT6 ,为结核病的预防提供有效亚单位疫苗。方法 设计含不同酶切位点的Ag85B和ESAT6引物 ,采用聚合酶链反应 (polymerasechainreaction ,PCR)的方法从结核分枝杆菌毒株H3 7Rv DNA中分别扩增出相应大小的DNA片段 ,将片段分别与PGEM T easy载体连接测序。将测序正确的Ag85B和ESAT6按照不同的酶切位点克隆入PPROEXHT表达载体 ,挑选出阳性克隆 ,将诱导的表达产物进行聚丙烯酰胺凝胶电泳 (SDS PAGE)分析 ,同时与含6个组氨酸 (histidine 6×his)的单克隆抗体 (monoclonalantibody ,mAb)进行固定化蛋白质免疫学测定(Western blot) ,将用含Ni 鳌合剂的Ni NTA亲合柱纯化的表达产物免疫小鼠 ,用结核分枝杆菌培养上清滤液蛋白 (culturefiltrateproteins ,CFP)作为抗原 ,酶联免疫吸附试验 (enzyme linkedimmunosorbentassay ,ELISA)测定免疫小鼠血清特异性抗体的滴度。结果 PCR获得的Ag85B和ESAT6序列与基因文库 (GenBank)报道的完全一致。两者在大肠杆菌DH5α株中融合表达的产物约为 370 0 0 ,与预计大小相吻合。Western blot结果显示 ,在相对分子量约 370 0 0处有表达产物与 6×hismAb特异性结合带。表达产物为包涵体 ,通过Ni NTA纯化系统 ,可得到纯化的目的蛋白。Ag8  相似文献   
970.
To define the gene content of the HLA class I region, cDNA selection was applied to three overlapping yeast artificial chromosomes (YACs) that spanned 1 megabase (Mb) of this region of the human major histocompatibility complex. These YACs extended from the region centromeric to HLA-E to the region telomeric to HLA-F. In addition to the recognized class I genes and pseudogenes and the anonymous non-class-I genes described recently by us and others, 20 additional anonymous cDNA clones were identified from this 1-Mb region. We also identified a long repetitive DNA element in the region between HLA-B and HLA-E. Homologues of this element were located at several sites in the human genome outside of the HLA complex. The portion of the HLA class I region represented by these YACs shows an average gene density as high as the class II and class III regions. Thus, the high gene density portion of the HLA complex is extended to more than 3 Mb.  相似文献   
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