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31.
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。  相似文献   
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A pulmonary artery (PA) sling is a very rare congenital cardiovascular anomaly, and only a few studies have reported PA slings in fetuses. The relationship of the PA, aorta, ductus arteriosus, and trachea can be evaluated in the 3‐vessel and 3‐vessel and trachea views during fetal echocardiography. A PA sling can be detected by abnormal positioning of the left PA in relation to the trachea when sweeping from the 3‐vessel view cranially to the 3‐vessel and trachea view. Here we report 3 cases of fetal PA slings and their follow‐ups. Two cases were confirmed by postnatal echocardiography, and the other case was confirmed by a cardiovascular cast after pregnancy termination. We emphasize that the 3‐vessel and 3‐vessel and trachea views are of crucial importance in the prenatal diagnosis of a PA sling.  相似文献   
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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.  相似文献   
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张金连    苑东敏  崔静  赵园园  王云云  杨帆  孙健平     《现代预防医学》2020,(8):1514-1518
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。  相似文献   
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从武汉抗疫中医药的投入使用情况,反思现代临床和国人所呈现出的中医药文化认同和就医习惯,探索其历史文化根源及社会因素与医学发展的内在关联。回顾历史,中医屡次临危受命,不负重托,如今大疫当前,中医药再次发挥了重要作用。故新时代探讨如何遵循中医药发展规律,传承精华、守正创新,坚持中医药原创优势,形成中医药学科优势整体化呈现的新模式医学,对提升全社会的中医药认知度具有重要意义。  相似文献   
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Ferroptosis is an iron-dependent novel cell death pathway. Deferoxamine, a ferroptosis inhibitor, has been reported to promote spinal cord injury repair. It has yet to be clarified whether ferroptosis inhibition represents the mechanism of action of Deferoxamine on spinal cord injury recovery. A rat model of Deferoxamine at thoracic 10 segment was established using a modified Allen's method. Ninety 8-week-old female Wistar rats were used. Rats in the Deferoxamine group were intraperitoneally injected with 100 mg/kg Deferoxamine 30 minutes before injury. Simultaneously, the Sham and Deferoxamine groups served as controls. Drug administration was conducted for 7 consecutive days. The results were as follows:(1) Electron microscopy revealed shrunken mitochondria in the spinal cord injury group.(2) The Basso, Beattie and Bresnahan locomotor rating score showed that recovery of the hindlimb was remarkably better in the Deferoxamine group than in the spinal cord injury group.(3) The iron concentration was lower in the Deferoxamine group than in the spinal cord injury group after injury.(4) Western blot assay revealed that, compared with the spinal cord injury group, GPX4, xCT, and glutathione expression was markedly increased in the Deferoxamine group.(5) Real-time polymerase chain reaction revealed that, compared with the Deferoxamine group, mRNA levels of ferroptosis-related genes Acyl-CoA synthetase family member 2(ACSF2) and iron-responsive element-binding protein 2(IREB2) were up-regulated in the Deferoxamine group.(6) Deferoxamine increased survival of neurons and inhibited gliosis. These findings confirm that Deferoxamine can repair spinal cord injury by inhibiting ferroptosis. Targeting ferroptosis is therefore a promising therapeutic approach for spinal cord injury.  相似文献   
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