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1.
目的了解不同机种军事飞行员运动心肺功能有无差异。方法飞行员分为高性能战斗机和普通战斗机两组,采用意大利COSMED运动心肺功能测试仪,选择自行车功率计运动方式,以25 W/min功率递增速率极量运动方案,进行运动心肺功能测试,比较两组运动心肺功能数据的主要指标。结果两组飞行员各207例完成运动心肺功能测试,两组的年龄、身高、体质量和体质量指数差异均无统计学意义(P均>0.05)。两组数据的主要指标中,除了峰值氧脉搏[高性能战斗机组(15.36±2.43)mL/bpm,普通战斗机组(14.95±2.13)mL/bpm]差异有统计学意义(P=0.038),其他差异均无统计学意义,而且各指标差异幅度均较小,高性能战斗机飞行员组的峰值氧脉搏高于普通战斗机组2.74%。结论综合比较,高性能战斗机和普通战斗机飞行员的运动心肺功能无明显差异,提示两组飞行员日常有氧运动训练效果一致,在转换飞行机种时,可以不受运动心肺功能的限制。 相似文献
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目的: 探究优化智能配药机器人调配技术参数对成品输液质量的影响。方法: 采用多因素正交试验优化配药机器人调配注射用头孢哌酮钠舒巴坦钠的溶媒体积、转针速度、推拉次数、抽拉角度、残留稀释、静置时间、二次配药参数,考察成品输液的不溶性微粒数;测定成品输液室温8 h内pH值、渗透压和不溶性微粒数;并对比机器调配与人工调配效率、手部意外刺伤发生率、药液残留量。结果: 注射用头孢哌酮钠舒巴坦钠最佳调配技术参数为溶解过程中溶媒体积10 mL、慢速转针、推拉5次、抽拉角度180°、残留稀释1次、静置时间10 s、选择二次配药,成品输液不溶性微粒数符合药典规定;室温8 h内成品输液性状、渗透压和pH值没有显著变化;配药机器人调配的药液残留量小于人工调配,无手部意外刺伤发生,一人同时操作2台机器的调配效率高于人工调配。结论: 通过正交试验优化配药机器人调配技术参数,能够提高调配的成品输液质量。 相似文献
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《Vaccine》2022,40(6):934-944
Respiratory Syncytial Virus (RSV) remains a leading cause of severe respiratory disease for which no licensed vaccine is available. We have previously described the derivation of an RSV Fusion protein (F) stabilized in its prefusion conformation (preF) as vaccine immunogen and demonstrated superior immunogenicity in naive mice of preF versus wild type RSV F protein, both as protein and when expressed from an Ad26 vaccine vector. Here we address the question if there are qualitative differences between the two vaccine platforms for induction of protective immunity. In naïve mice, both Ad26.RSV.preF and preF protein induced humoral responses, whereas cellular responses were only elicited by Ad26.RSV.preF. In RSV pre-exposed mice, a single dose of either vaccine induced cellular responses and strong humoral responses. Ad26-induced RSV-specific cellular immune responses were detected systemically and locally in the lungs. Both vaccines showed protective efficacy in the cotton rat model, but Ad26.RSV.preF conferred protection at lower virus neutralizing titers in comparison to RSV preF protein. Factors that may contribute to the protective capacity of Ad26.RSV.preF elicited immunity are the induced IgG2a antibodies that are able to engage Fcγ receptors mediating Antibody Dependent Cellular Cytotoxicity (ADCC), and the induction of systemic and lung resident RSV specific CD8 + T cells. These data demonstrate qualitative improvement of immune responses elicited by an adenoviral vector based vaccine encoding the RSV preF antigen compared to the subunit vaccine in small animal models which may inform RSV vaccine development. 相似文献
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《Vaccine》2019,37(41):6068-6075
Bluetongue (BT) is a hemorrhagic non-contagious, biting midge-transmitted disease of wild and domestic ruminants that is caused by bluetongue virus (BTV). Annual vaccination plays a pivotal role in BT disease control in endemic regions. Due to safety concerns of the current BTV multivalent live attenuated vaccine (LAV), a safe efficacious new generation subunit vaccine such as a plant-produced BT virus-like particle (VLP) vaccine is imperative. Previously, homogenous BTV serotype 8 (BTV-8) VLPs were successfully produced in Nicotiana benthamiana plants and provided protective immunity in sheep. In this study, combinations of BTV capsid proteins from more than one serotype were expressed and assembled to form chimaeric BTV-3 and BTV-4 VLPs in N. benthamiana plants. The assembled homogenous BTV-8, as well as chimaeric BTV-3 and chimaeric BTV-4 VLP serotypes, were confirmed by SDS-PAGE, Transmission Electron microscopy (TEM) and protein confirmation using liquid chromatography-mass spectrometry (LC-MS/MS) based peptide sequencing. As VP2 is the major determinant eliciting protective immunity, the percentage coverage and number of unique VP2 peptides detected in assembled chimaeric BT VLPs were used as a guide to assemble the most appropriate chimaeric combinations. Both plant-produced chimaeric BTV-3 and BTV-4 VLPs were able to induce long-lasting serotype-specific neutralizing antibodies equivalent to the monovalent LAV controls. Antibody levels remained high to the end of the trial. Combinations of homogenous and chimaeric BT VLPs have great potential as a safe, effective multivalent vaccine with the ability to distinguish between vaccinated and infected individuals (DIVA) due to the absence of non-structural proteins. 相似文献
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Mario Di Gioacchino Claudia Petrarca Alessia Gatta Gilda Scarano Anila Farinelli Loredana Della Valle 《Expert Review of Clinical Immunology》2020,16(5):513-525
ABSTRACT
Introduction
For several years now, medicine has been benefiting from the contribution of nanoparticles (NPs) technology for both diagnosis and therapy. They can be used as adjuvants, being capable per se of immune-modulating activity, or as carriers for molecules to be transported to a specific target, eventually loaded with specific ligands favoring specific uptake. 相似文献10.
Hiba K. Anis Gannon L. Curtis Alison K. Klika Nicolas S. Piuzzi Joshua Otiso Sandra S. Richter Wael K. Barsoum Carlos A. Higuera 《Journal of orthopaedic research》2020,38(2):431-437
Reducing airborne bioburden in total joint arthroplasty (TJA) is of critical importance. The efficacy of crystalline ultraviolet-C (C-UVC) filtration in reducing bioburden in a dynamic operating room (OR) environment has not been evaluated. We assessed whether C-UVC filtration reduced (i) total particle counts (TPC); (ii) viable particle counts (VPC); and (iii) colony-forming units (CFUs). Fifty primary TJA cases were performed in a positive-pressure OR; 25 cases with the C-UVC unit and 25 cases without. The air was sampled by a particle counter and an impact air sampler to measure particle counts and CFUs, respectively. To compare TPC, VPC, and CFU/m3 between groups, independent t tests and multivariate regression, adjusted for number of OR staff and door openings, were performed. The C-UVC group had significantly lower TPC (2.6 × 106 vs. 4.7 × 106 particles, p = 0.001) and VPC (18,605 vs. 27,516 particles, p = 0.001). There were fewer CFUs in the C-UVC group (10.9 CFU/m3 vs. 13.7 CFU/m3, p = 0.163). Multivariate analysis identified C-UVC filtration as a significant predictor of decreased TPC (β = −0.44, p = 0.002) and VPC (β = −0.47, p = 0.001) after accounting for door openings and number of OR staff. The reduction in CFUs was not significant on multivariate analysis. In this prospective pilot study, a C-UVC air disinfection and recirculation unit led to a significant reduction in both TPC and VPC and a non-significant reduction in CFU. Statement of clinical significance: Further studies are needed to investigate the effects of C-UVC filtration units on surgical-site infection rates. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 38:431-437, 2020 相似文献