神经肽-1受体拮抗剂对哮喘大鼠气道平滑肌细胞内钙离子浓度的影响

目的 探讨神经肽-1受体(NK-1R)拮抗剂WIN62577对哮喘大鼠气道平滑肌细胞(ASMC)内钙离子浓度的影响及其调节机制,为哮喘气道反应性的治疗寻找新的途径.方法 采用OVA吸入法制作哮喘模型.原代培养大鼠ASMC.细胞内钙离子荧光成像系统检测ASMC内钙离子浓度.Real-time PCR检测各组ASMC中SERCA2mRNA(肌浆网钙ATP酶)及IP3RmRNA(三磷酸肌醇受体)表达,组间采用单因素方差分析比较各组间差异,P<0.05为差异有显著性.结果 哮喘组ASMC中钙离子浓度较正常组增高;正常组ASMC内钙离子浓度在P物质干预后迅速升高;哮喘组ASMC内钙离子浓度在WIN62577干预后迅速下降.正常组及NK-1R拮抗剂干预哮喘ASMC组中SERCA2mR NA表达与哮喘组比较,差异均有显著性(P<0.05);哮喘组ASMC中IP3RmRNA表达与正常组ASMC比较差异无显著性(P>0.05);NK-1R拮抗剂干预哮喘ASMC组IP3RmRNA表达较哮喘组比较差异有显著性(P<0.05).结论 哮喘大鼠ASMC中SERCA2表达减少,WIN62577通过提高SERCA2及降低IP3K表达从而降低细胞内钙离子浓度改善哮喘气道高反应性.     

Experimental-Numerical Study on the Flexural Ultimate Capacity of Prestressed Concrete Box Girders Subjected to Collision

Precise evaluation for flexural ultimate capacity of bridges which are subjected to the collision of over-height trucks is essential for making decisions on corresponding maintenance, strengthening or replacement. When the span of a cross-line continuous bridge with a double-box girder was hit by an overly high vehicle, the concrete floor of one girder was severely damaged, and part of the prestressed strands and reinforcements in the girder were broken. After the double-box girder was removed and separated into two single box girders, the ultimate flexural capacity of both box girders was studied by destructive tests, and a comparison was made between the damaged and undamaged girders. Moreover, finite element analysis was conducted to simulate the failure process. The results show that the flexural bearing capacity of the damaged box girder decreased by 33%, but it was still 1.07 times greater than the design bearing capacity, which basically meets the design requirements. Also, the damaged box girder showed a desirable serviceable limit state for three-axle vehicles and five-axle vehicles, but showed an undesirable serviceable limit state for six-axle vehicles. This study shows that repairing or strengthening the damaged span may be better than demolishing and rebuilding the whole superstructure bridge.     

Veganism does not reduce the risk of the metabolic syndrome in a Taiwanese cohort

The purpose of the present study was to assess the risk of the metabolic syndrome (MS) with vegan, pescovegetarian, lactovegetarian and nonvegetarian diets in Taiwan. The design was a retrospective cohort study using secondary data analysis from a Taiwan longitudinal health check-up database provided by MJ Health Screening Center during 1996-2006. A total of 93209 participants were classified as vegans (n=1116), pescovegetarians (n=2461), lactovegetarians (n=4313) and nonvegetarians (n=85319) by food frequency list of self-administered questionnaire at baseline. The association between MS or MS components and different dietary groups was evaluated using Cox proportional-hazards regression models with adjustment for confounders. During the mean 3.75 years of follow up, a total 8006 MS incident cases occurred and the incidence of MS was 229 (95% CI, 224, 234) per 10000 person year. Compared with vegans, hazard ratios of MS for nonvegetarians, pescovegetarians, lactovegetarians were 0.75 (95% CI, 0.64, 0.88), 0.68 (95% CI, 0.55, 0.83) and 0.81 (95% CI, 0.67, 0.97) after adjusting for sex, age, education status, smoking status, drinking status, physical activity at work and leisure, respectively. As for MS components, nonvegetarians and pescovegetarians had 0.72 (95% CI, 0.62, 0.84), 0.70 (95% CI, 0.57, 0.84) times risk of developing low high density lipoprotein cholesterol (HDL-C), while nonvegetarians had 1.16 (95% CI, 1.02, 1.32) times risk of developing high fasting plasma glucose. Our data suggest that the vegan diets did not decrease the risk of metabolic syndrome compared with pescovegetarian, lactovegetarian and nonvegetarian diets in a Taiwanese cohort.     

COVID-19期间病案统计管理策略

新冠肺炎疫情发生以来,给我国的卫生预防工作带来了极大地挑战,考验着医院在特殊时期的管理能力,特别是对记录着患者诊疗信息的病案管理提出新的要求.为规范COVID-19期间的病案管理工作,本文就电子病历资料的填写、质控、特殊标记及相对传统电子病案管理方式进行探索,按照战时医院感染防控要求对纸质病案管理进行优化改进,特别是在...     

Study on the Polycrystalline Mechanism of Polycrystalline Diamond Synthesized from Graphite by Direct Detonation Method

In this paper, a polycrystalline diamond was synthesized by the direct detonation method using graphite as the carbon source. By comparing the numbers of the obtained diamond particles and the original graphite particles, it was found that when the graphite phase transformed into the polycrystalline diamond during the detonation process, a single graphite particle would form multiple diamond nuclei, and the nuclei would grow simultaneously to form polycrystals. Accordingly, a validation experiment was designed, which added different ratios of inert additives while keeping the ratio of graphite to hexogen (RDX) unchanged. It was found that increasing the ratio of inert additives within a certain range could increase the grain size of a polycrystalline diamond, which is consistent with the obtained polycrystalline mechanism.     

Abnormal Micronutrient Intake Is Associated with the Risk of Periodontitis: A Dose–response Association Study Based on NHANES 2009–2014

The association between micronutrient intake and the risk of periodontitis has received much attention in recent years. However, most studies focused on the linear relationship between them. This study aimed to explore the dose–response association between micronutrient intake and periodontitis. A total of 8959 participants who underwent a periodontal examination, and reported their micronutrient intake levels were derived from the US National Health and Nutrition Examination Survey (NHANES, 2009–2014) database. Logistic regression was performed to evaluate associations between micronutrient intake and periodontitis after propensity score matching (PSM), and restricted cubic splines (RCS) analysis was conducted to explore the dose–response associations. Following PSM, 5530 participants were included in the RCS analysis. The risk of periodontitis was reduced with sufficient intake of the following micronutrients: vitamin A, vitamin B1, vitamin B2, and vitamin E. In addition, the risk of periodontitis was increased with excessive intake of the following micronutrients: vitamin B1 (1.8 mg/day, males; 1.3 mg/day, females), vitamin C (90 mg/day, males), and copper (1.1 mg/day, combined). In conclusion, a linear association was found between vitamin A, vitamin B2, vitamin C, and copper and periodontitis—namely, a sufficient intake of vitamin A and vitamin B2 might help reduce the prevalence of periodontitis; by contrast, a high intake of vitamin C and copper increased the risk. In addition, a nonlinear dose–response association was found for the incidence of periodontitis with vitamin B1 and vitamin E. When within reasonable limits, supplemental intake helped reduce the prevalence of periodontitis, while excessive intake did not help significantly and might even increase the risk. However, confounding factors, such as health awareness, should still be considered.     

Study on Wear Mechanism of Helical Gear by Three-Body Abrasive Based on Impact Load

This study aimed to explore the wear characteristics and evolution mechanisms of large-scale wind power gears under the impact load of particles of the three-body abrasive Al₂O₃ (0.2 mg/mL) from four aspects: oil analysis, vibration analysis, amount of gear wear, and tooth-surface-wear profile analysis. A magnetic powder brake was used to simulate the actual working conditions. Combined with the abrasive particle monitoring and the morphology analysis of the tooth-surface-wear scar, by setting quantitative hard particles in the lubricating oil, the gears are mainly operated in the abrasive wear state, and wear monitoring and wear degree analysis are carried out for the whole life cycle of the gears. Oil samples were observed and qualitatively analyzed using a particle counter, a single ferrograph, a metallographic microscope, and a scanning electron microscope. The experiments demonstrate that the initial hard particles have a greater impact in the early wear stage of the gears (<20 h), and abrasive particle concentration increases by 30%. This means that Al₂O₃ particles accelerate the gear wear during the running-in period. The loading method of the impact load on the oblique gear exacerbates the abrasion particle wear and expands the stress concentration, which reduces the surface of large milling particles on the surface, and reduces the width of the tooth (the part above the pitch line is severely worn), which causes the gear to break into failure. The research provides help for analyzing the mechanism of abrasive wear of gears and predicting wear life.     

支气管哮喘患者诱导痰嗜酸细胞活化趋化因子-2和IL-17表达及临床意义

目的：探讨支气管哮喘患者诱导痰中嗜酸细胞活化趋化因子-2（Eotaxin-2）和IL-17表达水平及临床意义。方法：选择32例支气管哮喘患者[轻度（9例）、中度（14例）、重度（10例）]和15例正常对照者，通过人工诱导的方法获得痰液，ELISA法检测Eotaxin-2、IL-17表达水平。结果：中、重度哮喘患者诱导痰中嗜酸粒细胞、中性粒细胞、Eotaxin-2和IL-17水平均较轻度组、正常对照组明显升高（P均〈0．05）。Eotaxin-2和IL-17水平随哮喘程度加重而明显增加。嗜酸粒细胞与Eotaxin-2水平、中性粒细胞与IL-17水平呈正相关（r分别为0．325、0．418，P均〈0．05），经过糖皮质激素吸入治疗5周后，哮喘患者诱导痰中嗜酸粒细胞、Eotaxin-2较治疗前下降（P〈0．05），而治疗前、后中性粒细胞、IL-17水平差异无显著意义（P〉0．05）。结论：诱导痰中Eotaxin-2及IL-17水平可能作为判断哮喘气道炎症程度的参考指标，糖皮质激素的治疗不能显著降低诱导痰中IL-17水平。     

淡色库蚊对4种杀虫剂的抗药性研究

目的了解大连市淡色库蚊对敌敌畏、仲丁威、溴氰菊酯及高效氯氰菊酯的抗药性现状,为制定防治对策提供科学依据。方法强迫接触法。结果自然品系淡色库蚊对敌敌畏、仲丁威抗性较低,抗性倍数分别为0.36和1.96;对溴氰菊酯和高效氯氰菊酯抗性较高,抗性倍数分别为43.75和118.89。结论应加强蚊虫抗药性监测,并根据具体情况,采用适宜防蚊方法,合理的使用杀虫剂,预防与减缓杀虫剂抗性的产生和发展。