Er:YAG激光桩道预处理的研究进展

本文回顾了Er:YAG激光活化根管冲洗技术的最新研究进展,包括光子诱导光声流(photon initiated photoacoustic streaming,PIPS)技术和冲击波增强发射光声流(shock wave enhanced emission photoacoustic streaming,SWEEPS)技术,探讨Er:YAG激光预处理桩道的原理、优点以及对纤维桩粘接强度的影响,以期为临床选择适宜的桩道处理方法提供新思路。     

An epidemiologic study of sleep-disordered breathing in a large sample of Chinese adolescents

Journal of Public Health - Sleep-disordered breathing (SDB) is common among adolescents and is associated with short- and long-term consequences. Data on the prevalence and epidemiologic...     

Interactions between cancer cells and immune cells drive transitions to mesenchymal-like states in glioblastoma

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Biomechanical behavior of brain injury caused by sticks using finite element model and Hybrid-III testing

Objective: To study the biomechanical mechanism of head injuries beaten with sticks, which is common in the battery or assaultive cases. Methods: In this study, the Hybrid-III anthropomorphic test device and finite element model (FEM) of the total human model for safety (THUMS) head were used to determine the biomechanical response of head while being beaten with different sticks. Total eight Hybrid-III tests and four finite element simulations were conducted. The contact force, resultant acceleration of head center of gravity, intracranial pressure and von Mises stress were calculated to determine the different biomechanical behavior of head with beaten by different sticks. Results: In Hybrid-III tests, the stick in each group demonstrated the similar kinematic behavior under the same loading condition. The peak values of the resultant acceleration for thick iron stick group, thin iron stick group, thick wooden stick group and thin wooden stick group were 203.4 g, 221.1 g, 170.5 g and 122.2 g respectively. In finite element simulations, positive intracranial pressure was initially observed in the frontal comparing with negative intracranial pressure in the contra-coup site. Subsequently the intracranial pressure in the coup site was decreasing toward negative value while the contra-coup intracranial pressure increasing toward positive values. Conclusions: The results illustrated that the stiffer and larger the stick was, the higher the von Mises stress, contact force and intracranial pressure were. We believed that the results in the Hybrid-III tests and THUMS head simulations for brain injury beaten with sticks could be reliable and useful for better understanding the injury mechanism.     

血清谷丙转氨酶水平与不同性别2型糖尿病患病的关系

目的 探讨血清谷丙转氨酶（ALT）与新诊2型糖尿病（T2DM）患病风险之间的关联，为T2DM的防治提供科学依据。方法 采用4阶段分层随机抽样的方法选取2006年和2009年参与青岛糖尿病预防项目的研究对象男性3 012例、女性4 422例，采用Pearson相关检验分析不同性别ALT与FPG、2 h PG的相关性，并利用多因素logistic回归分析ALT与新诊T2DM患病的关系。结果 男性中，ALT与空腹血浆血糖（FPG）、餐后2 h血浆血糖（2 h PG）的Pearson相关系数分别为0.088、0.080（均P＜0.01）；多因素logistic回归显示，在调整了年龄、BMI、糖尿病家族史、城乡、教育、婚姻、收入、吸烟及饮酒状况等混杂因素后，ALT的第4分位（Q4）组新诊T2DM患病风险是第1分位（Q1）组的1.832倍（OR = 1.832，95% CI:1.324～2.534，P＜0.01）。女性中，ALT与FPG、2h PG的Pearson相关系数分别为0.065、0.108（均P＜0.01）；多因素logistic回归显示，在调整了年龄、BMI、糖尿病家族史、城乡、教育、婚姻、收入、吸烟及饮酒状况等混杂因素后，ALT的第4分位（Q4）组新诊T2DM患病风险是第1分位（Q1）组的1.445倍（OR = 1.445，95% CI:1.087～1.919，P＜0.05）。结论 在男、女性人群中，ALT水平升高与T2DM患病相关，且这种相关性不受年龄、BMI、糖尿病家族史等的影响。