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991.
In 2019,an outbreak of Mycoplasma pneumoniae (M.pneumoniae) occurred at a military academy in China.The attack rate (10.08%,60/595) was significantly different among the units.High-intensity training and crowded environments to which cadets are exposed are the high risk factors for the outbreak of M.pneumoniae.In-time prevention and control measures effectively controlled the spread of the epidemic.  相似文献   
992.
The aim of this review was to provide an evidenced‐based review of the genetic basis of the corneal endothelial dystrophies. A review of the English language peer‐reviewed literature describing the molecular genetic basis of posterior polymorphous corneal dystrophy (PPCD), congenital hereditary endothelial dystrophy (CHED), Fuchs endothelial corneal dystrophy (FECD) and X‐linked endothelial corneal dystrophy (XECD) was performed. Mutations in several genes have been implicated as playing a pathogenic role in the corneal endothelial dystrophies: VSX1 mutations in PPCD1; COL8A2 mutations in PPCD2 and FECD; ZEB1 mutations in PPCD3 and FECD; and SLC4A11 mutations in CHED2 and FECD. However, linkage, association and familial segregation analyses support a role of only one gene in each corneal endothelial dystrophy: ZEB1 in PPCD3, SLC4A11 in CHED2 and COL8A2 in FECD (early onset). In addition, insufficient evidence exists to consider the autosomal dominant form of CHED (CHED1) as distinct from PPCD. An accurate classification of the corneal endothelial dystrophies requires a critical review of the evidence to support the role of each suggested chromosomal locus, gene and genetic mutation associated with a corneal endothelial dystrophy. Only after the separation of evidence from opinion is performed can a critical examination of the molecular pathways that lead to endothelial dysfunction in each of these disorders be accurately performed.  相似文献   
993.
ObjectiveClear cell sarcoma of the kidney (CCSK) is the second-most common but extremely rare primary renal malignancy in children after Wilms'' tumor. The aims of this study were to evaluate the imaging features that could distinguish between CCSK and Wilms'' tumor and to assess the features with diagnostic value for identifying CCSK.Materials and MethodsWe reviewed the initial contrast-enhanced abdominal-pelvic CT scans of children with CCSK and Wilms'' tumor between 2010 to 2019. Fifty-eight children (32 males and 26 females; age, 0.3–10 years), 7 with CCSK, and 51 with Wilms'' tumor, were included. The maximum tumor diameter, presence of engorged perinephric vessels, maximum density of the tumor (Tmax) of the enhancing solid portion, paraspinal muscle, contralateral renal vein density, and density ratios (Tmax/muscle and Tmax/vein) were analyzed on the renal parenchymal phase of contrast-enhanced CT. Fisher''s exact tests and Mann-Whitney U tests were conducted to analyze the categorical and continuous variables, respectively. Logistic regression and receiver operating characteristic curve analyses were also performed.ResultsThe age, sex, and tumor diameter did not differ between the two groups. Engorged perinephric vessels were more common in patients in the CCSK group (71% [5/7] vs. 16% [8/51], p = 0.005). Tmax (median, 148.0 vs. 111.0 Hounsfield unit, p = 0.004), Tmax/muscle (median, 2.64 vs. 1.67, p = 0.002), and Tmax/vein (median, 0.94 vs. 0.59, p = 0.002) were higher in the CCSK compared to the Wilms'' group. Multiple logistic regression revealed that engorged vessels (odds ratio 13.615; 95% confidence interval [CI], 1.770–104.730) and Tmax/muscle (odds ratio 5.881; 95% CI, 1.337–25.871) were significant predictors of CCSK. The cutoff values of Tmax/muscle (86% sensitivity, 77% specificity) and Tmax/vein (71% sensitivity, 86% specificity) for the diagnosis of CCSK were 1.97 and 0.76, respectively.ConclusionPerinephric vessel engorgement and greater tumor enhancement (Tmax/muscle > 1.97 or Tmax/vein > 0.76) are helpful for differentiating between CCSK and Wilms'' tumor in children aged below 10 years.  相似文献   
994.
995.
Zhao  Jia-min  Ji  Ling-ling  Han  Meng-qi  Mou  Qing-nan  Chu  Guang  Chen  Teng  Du  Shao-yi  Hou  Yu-xia  Guo  Yu-cheng 《International journal of legal medicine》2021,135(5):1887-1901
International Journal of Legal Medicine - Lips are the main part of the lower facial soft tissue and are vital to forensic facial approximation (FFA). Facial soft tissue thickness (FSTT) and linear...  相似文献   
996.
胡汉  茹文鑫  岳建伟  周婷  黄国伟  杨清  高玉霞 《军事医学》2021,45(4):293-298,306
目的 探究外周血白细胞端粒长度(LTL)和线粒体基因拷贝数(mtDNA?CN)对急性心肌梗死(AMI)的预测价值,并从端粒酶逆转录酶(TERT)和线粒体氧化损伤的角度探讨其相关机制.方法 选取AMI患者80例,并选同期行冠脉造影检查且结果显示冠脉大致正常者80例作为对照.收集研究对象的临床资料和空腹全血,以qPCR法检测外周血LTL、TERT mRNA、mtDNA?CN和线粒体氧化损伤程度,采用Spearman相关分析评估上述指标间的相关性.采用多因素Logistic回归分析LTL和mtDNA?CN与AMI发生风险的关系,以受试者工作曲线(ROC)评价LTL和mtDNA?CN对AMI诊断的预测价值.结果 AMI组患者外周血LTL、TERT mRNA表达水平和mtDNA?CN均显著低于对照组,线粒体氧化损伤水平显著高于对照组,差异均具有统计学意义(P<0.05).在AMI组和对照组中,LTL分别与TERT mRNA的表达水平和mtDNA?CN呈显著正相关,与线粒体氧化损伤水平呈显著负相关(均P<0.05).在AMI组中,mtDNA?CN与线粒体氧化损伤水平呈显著负相关(P=0.03),但在对照组中两者相关性无统计学意义(P=0.20).Logistic回归分析结果表明,长LTL和高mtDNA?CN是AMI的保护因素;ROC曲线分析结果表明,LTL、mtDNA?CN以及两者联合预测AMI的曲线下面积(AUC)分别为0.748、0.704、0.767.结论 外周血LTL和mtDNA?CN对AMI具有一定的预测诊断价值.AMI患者外周血LTL的缩短可能与TERT mRNA表达的降低有关,外周血白细胞线粒体氧化损伤水平的升高可能是mtDNA?CN降低和LTL缩短的重要原因.  相似文献   
997.
998.
The gastrointestinal distribution of glycinin in pigs at different growth stages was investigated in this study. Fifteen healthy General No. 1 barrows weaned on the 28th day were randomly assigned to three groups with five replicates: five weanling, five growing and five finishing. All pigs received diets with non-soya bean ingredients in non-experimental periods, while the pigs received diets containing 4% purified glycinin in experimental periods. Binding of anti-glycinin antibody was detected using a labelled streptavidin–peroxidase complex method to determine the gastrointestinal distribution of glycinin. The results indicated that there was a significant difference on the gastrointestinal mucosal distribution of glycinin between pigs of different ages. Glycinin in growers was higher than piglets and lower than finishers (P<0.001). The highest content of glycinin was in the distal jejunum and ileum for piglets, and in distal jejunum for growers and finishers (P<0.05).  相似文献   
999.
Neurological abnormalities identified via neuroimaging are common in patients with Alzheimer's disease. However, it is not yet possible to easily detect these abnormalities using head computed tomography in the early stages of the disease. In this review, we evaluated the ways in which modern imaging techniques such as positron emission computed tomography, single photon emission tomography, magnetic resonance spectrum imaging, structural magnetic resonance imaging, magnetic resonance diffusion tensor imaging, magnetic resonance perfusion weighted imaging, magnetic resonance sensitive weighted imaging, and functional magnetic resonance imaging have revealed specific changes not only in brain structure, but also in brain function in Alzheimer's disease patients. The reviewed literature indicated that decreased fluorodeoxyglucose metabolism in the temporal and parietal lobes of Alzheimer's disease patients is frequently observed via positron emission computed tomography. Furthermore, patients with Alzheimer's disease often show a decreased N-acetylaspartic acid/creatine ratio and an increased myoinositol/creatine ratio revealed via magnetic resonance imaging. Atrophy of the entorhinal cortex, hippocampus, and posterior cingulate gyrus can be detected early using structural magnetic resonance imaging. Magnetic resonance sensitive weighted imaging can show small bleeds and abnormal iron metabolism. Task-related functional magnetic resonance imaging can display brain function activity through cerebral blood oxygenation. Resting functional magnetic resonance imaging can display the functional connection between brain neural networks. These are helpful for the differential diagnosis and experimental study of Alzheimer's disease, and are valuable for exploring the pathogenesis of Alzheimer's disease.  相似文献   
1000.
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