减阻牵张正畸牙移动过程中牙周组织超微结构变化的研究

目的：研究减阻牵张正畸牙移动过程中牙周组织超微结构的变化，为此方法矫治正畸牙提供理论依据。方法：将6只杂种犬随机分为2周、3周、6周二组，拔除下颌两侧第二前磨牙，随机选择一侧为实验侧，实施减阻牵张措施加快牙齿移动速度，另一侧为空白对照侧，实验侧加力2周、固定保持1周、4周时，制备移动牙标本，进行透射电镜观察。结果：对照侧无明显成骨及破骨迹象；加力2周组张力侧成骨细胞、成纤维细胞的胞浆内高尔基体、内质网等细胞器非常丰富，分泌功能旺盛；压力侧破骨细胞增多，高尔基体发达，线粒体、溶酶体增多，成纤维细胞细胞器发达，间充质细胞、活跃的巨噬细胞增多；随着固定保持时间的延长，实验侧与对照侧超微结构的差异变小。结论：正畸牙压力侧减阻后，在强、高频率加力方式作片用下，牙周组织细胞功能旺盛、改建活跃，无不可逆的细胞变性坏死变化。     

几种消毒剂对藻酸盐印模材料的消毒效果

作者为了选择对藻酸盐印模材料有效的消毒剂和消毒方法，采用２％碱性戊二醛、１％过氧乙酸、２％甲醛对３０名受试者的藻酸盐印模进行消毒，并在消毒前后进行细菌培养及鉴定。结果发现：消毒前的印模有９种细菌被检出，污染率高达９６％；消毒后的印模细菌检出率为零。作者认为，本研究所用消毒剂、消毒方法效果良好，值得沿用。     

Epidemiologic Features,Radiological Findings and Clinical Outcomes of 19 Patients with COVID-19 in a Single Center in Beijing,China

Objective To describe the epidemiologic, clinical, laboratory, and radiological characteristics and prognoses of COVID-19 confirmed patients in a single center in Beijing, China. Methods The study retrospectively included 19 patients with nucleic acid-confirmed SARS-CoV-2 infection at our hospital from January 20 to March 5, 2020. The final follow-up date was March 14, 2020. The epidemiologic and clinical information was obtained through direct communication with the patients or their family members. Laboratory results retrieved from medical records and radiological images were analyzed both qualitatively by two senior chest radiologists as well as quantitatively via an artificial intelligence software. Results We identified 5 family clusters (13/19, 68.4％) from the study cohort. All cases had good clinical prognoses and were either mild (3/19) or moderate (16/19) clinical types. Fever (15/19, 78.9％) and dry cough (11/19, 57.9％) were common symptoms. Two patients received negative results for more than three consecutive viral nucleic acid tests. The longest interval between an initial CT abnormal finding and a confirmed diagnosis was 30 days. One patient's nucleic acid test turned positive on the follow-up examination after discharge. The presence of radiological abnormalities was non-specific for the diagnosis of COVID-19. Conclusions COVID-19 patients with mild or no clinical symptoms are common in Beijing, China. Radiological abnormalities are mostly non-specific and massive CT examinations for COVID-19 screening should be avoided. Analyses of the contact histories of diagnosed cases in combination with clinical, radiological and laboratory findings are crucial for the early detection of COVID-19. Close monitoring after discharge is also recommended.     

Effect of Focused Cardiac Ultrasound in Combination with Lung Ultrasound on Critically Ill Patients:A Multicenter Observational Study in China

Objective Focused cardiac ultrasound (FCU) and lung ultrasound (LU) are increasingly being used in critically ill patients.This study aimed to investigate the effect of FCU in combination with LU on these patients and to determine if the timing of ultrasound examination was associated with treatment change.Methods This is a multicenter cross-sectional observational study.Consecutive patients admitted to the intensive care unit (ICU) were screened for enrollment.FCU and LU were performed within the first 24 h,and treatment change was proposed by the performer based on the ultrasound results and other clinical conditions.Results Among the 992 patients included,502 were examined within 6 h of ICU admission (early phase group),and 490 were examined after 6 h of admission (later phase group).The early phase group and the later phase group had similar proportions of treatment change (48.8％ vs.49.0 ％,x2 =0.003,P=0.956).In the multivariable analysis,admission for respiratory failure was an independent variable associated with treatment change,with an odds ratio (OR) of 2.357[95 ％ confidence interval (CI):1.284-4.326,P=0.006];the timing of examination was not associated with treatment change (OR=0.725,95％CI:0.407-1.291,P=0.275).Conclusions FCU in combination with LU,whether performed during the early phase or later phase,had a significant impact on the treatment of critically ill patients.Patients with respiratory failure were more likely to experience treatment change after the ultrasound examination.     

遗传性神经系统离子通道病基因治疗的研究进展

目的遗传性神经系统离子通道病现有的治疗方法往往难以控制病情或者患者耐受度较低,因此探索新的治疗方法势在必行。基因治疗在多项研究中显示可能应用于神经系统疾病,并可能成为未来遗传性神经系统离子通道病的有效治疗手段。同时,光遗传学、化学遗传学方法、基因编辑技术的不断进步也为遗传性神经系统离子通道病的基因治疗提供了良好的发展基础。我们将就遗传性神经系统离子通道病基因治疗的方法机制、转导载体、启动子及给药途径作一综述。