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991.
Coronavirus disease 2019 (COVID-19) was first detected in China in December 2019, and declared as a pandemic by the World Health Organization (WHO) on March 11, 2020.To study the clinical features of patients with COVID-19, we analyzed the correlation between some inflammation-related indicators in patients’ serum and the severity of the disease, especially PV (pneumonia volume under CT scan) and pneumonia volume ratio (PVR).Sixty-six COVID-19 patients in Huai’an, China were selected as the research subjects. We collected the clinical data, including general characteristics, clinical symptoms, serum test results and CT performance, explored the relationship between inflammation-related indexes, oxygenation index, PV, PVR, while indicators of mild to moderate patients and severe patients were compared.The most prominent manifestations of COVID-19 patients were fever (47, 71.2%); cough (41, 62.1%), with or without respiratory and other systemic symptoms; There was no difference in gender (P = .567) and age (P = .865) between mild to moderate and severe groups. High sensitivity C-reactive protein (hs-CRP), erythrocyte sedimentation rate (ESR), and interleukin-6 (IL-6) of overall patients were higher than the normal range (P < .001, respectively). hs-CRP was negatively correlated with oxygenation index (OI) (r = –0.55), whereas positively correlated with PV, PVR and ESR (r = 0.89; r = 0.87; r = 0.47, respectively); ESR was negatively correlated with OI (r = –0.45), meanwhile it was positively correlated with PV and PVR (r = 0.44; r = 0.46, respectively). OI was negatively correlated with PV and PVR (r = –0.6, respectively). PV had a clear correlation with PVR (r = 1). Severe patients’ hs-CRP, PV, PVR were higher than mild to moderate group (P = .006; P = .001; P < .001, respectively), but OI was lower (P < .001).The clinical features of COVID-19 were similar to general viral pneumonia. hs-CRP, ESR showed a certain correlation with the PV and PVR, which might play a certain role in assessing the severity of COVID-19. 相似文献
992.
993.
目的 探讨Bi PAP呼吸机联合7 L/min的氧气驱动雾化吸入在COPD患者中的价值.方法 选取2017年12月至2020年12月期间在我院治疗的68例COPD患者作为对象,2017年12月至2018年12月期间入院患者作为对照组33例,2019年1月至2020年12月期间入院患者作为观察组35例.对照组在常规治疗基... 相似文献
994.
Jingjing Yan Weidong Fei Qianqian Song Yao Zhu Na Bu Li Wang Mengdan Zhao Xiaoling Zheng 《Drug delivery》2022,29(1):2296
The emerging cell membrane (CM)-camouflaged poly(lactide-co-glycolide) (PLGA) nanoparticles (NPs) (CM@PLGA NPs) have witnessed tremendous developments since coming to the limelight. Donning a novel membrane coat on traditional PLGA carriers enables combining the strengths of PLGA with cell-like behavior, including inherently interacting with the surrounding environment. Thereby, the in vivo defects of PLGA (such as drug leakage and poor specific distribution) can be overcome, its therapeutic potential can be amplified, and additional novel functions beyond drug delivery can be conferred. To elucidate the development and promote the clinical transformation of CM@PLGA NPs, the commonly used anucleate and eukaryotic CMs have been described first. Then, CM engineering strategies, such as genetic and nongenetic engineering methods and hybrid membrane technology, have been discussed. The reviewed CM engineering technologies are expected to enrich the functions of CM@PLGA for diverse therapeutic purposes. Third, this article highlights the therapeutic and diagnostic applications and action mechanisms of PLGA biomimetic systems for cancer, cardiovascular diseases, virus infection, and eye diseases. Finally, future expectations and challenges are spotlighted in the concept of translational medicine. 相似文献
995.
To deeply understand the adsorption process of oxygen on the surface of a plutonium gallium system and to reveal the chemical reaction mechanism at the initial stage of oxidative corrosion on the surface of plutonium gallium alloy at a theoretical level, the adsorption behavior of oxygen molecules on the surface of a plutonium gallium system was investigated by a first-principles approach based on density flooding theory. The results show that the molecular bond length increases and finally breaks when the surface oxygen molecule is adsorbed on the surface of plutonium gallium system and dissociates into two atomic states. The most likely adsorption position of oxygen molecules on the surface of plutonium gallium system is hole-site vertical adsorption with the adsorption energy size of 10.7 eV. The bonding between oxygen atom and surface is mainly due to the overlapping hybridization of Pu-6s, Pu-7s, Pu-6d, Ga-3d and O-2p orbitals. Oxygen molecules mainly interact with the atoms of the first layer on the surface of the plutonium gallium system. The oxygen atoms after stable adsorption are able to diffuse to the subsurface of the plutonium gallium system after overcoming the energy barrier of 16.7 eV and form a stable structure. The research results reveal the initial reaction process and adsorption law of oxygen on the surface of plutonium gallium system from microscopic level, which is helpful to further explore the surface corrosion prevention technology of plutonium gallium system and improve the reliability and safety of plutonium gallium alloy components. 相似文献
996.
Zheng Chen Xifeng Hu Xiangdong Wu Yu Li Zhen Ding Qinghua Zeng Tong Wan Jingyi Yin Huansheng Wu 《Viruses》2022,14(7)
Porcine circovirus-like virus (PCLV) is a member of circovirus that contains a single-strand DNA genome, which may be one of the pathogens that causes diarrheal symptoms in pigs. The Rep protein encoded by the genome of PCLV may be responsible for viral genome replication. The development of serological detection methods for PCLV is of great necessity for clinical diagnosis, as well as epidemiological investigations. Therefore, this study attempted to build an indirect enzyme-linked immunosorbent assay (ELISA) to examine antibodies against PCLV based on the His-tagged recombinant Rep protein. Full-length PCLV Rep protein was induced and expressed in E. coli and was purified as an antigen to establish an ELISA detection kit. The purified Rep protein was used to inject into mice to produce specific antibodies. There was no cross-reaction of Rep-based ELISA with antisera against other porcine viruses. The intra-assay and inter-assay coefficient variations (CVs) were 0.644–8.211% and 0.859–7.246%, respectively, indicating good repeatability. The non-cross-reaction with TGEV, PRRSV and PCV2 testing showed high sensitivity and high specificity for this ELISA assay. A total of 1593 serum samples collected from different pig farms in Jiangxi Province were tested for anti-PCLV Rep antibodies, and 284 (17.83%) of the 1593 samples were Rep antibody positive. Altogether, the indirect ELISA detection tool developed in this study could be applied to examine serum of PCLV antibodies with good repeatability, high sensitivity and high specificity. In addition, field sample detection results suggested that the PCLV antibody has a low prevalence in pig populations in Jiangxi Province of China. 相似文献
997.
目的:分析体外循环胸腔镜配合纤维软镜心脏手术常出现的危险因素。方法选择心、肺功能良好的杂种犬40只,随机分为实验组(20只,房间隔和室间隔缺损各10只)和对照组(20只,房间隔和室间隔缺损各10只)。实验组进行胸腔镜配合纤维软镜体外循环下同时模拟房间隔和室间隔缺损修补术、右室流出道疏通术。对照组进行胸腔镜体外循环下房间隔和室间隔缺损修补术、右室流出道疏通术。分别记录两组动物手术前后平均动脉压、中心静脉压、心率等,以及术中上下腔静脉套带时间、手术时间、体外循环时间、主动脉阻闭时间和转机时间等。观察手术并发症发生情况。结果术后实验组动物平均动脉压、中心静脉压、心率等均明显优于对照组,差异均有统计学意义(P<0.05);术中实验组动物上下腔静脉套带时间、手术时间、体外循环时间、主动脉阻闭时间、转机时间等也均明显优于对照组,差异均有统计学意义(P<0.05)。结论胸腔镜配合纤维软镜体外循环下同时模拟房间隔和室间隔缺损修补术、右室流出道疏通术可获得良好的临床效果,适合在临床广泛应用。 相似文献
998.
Saura C. Sahu Joyce Njoroge Steven M. Bryce Jiwen Zheng John Ihrie 《Journal of applied toxicology : JAT》2016,36(4):521-531
Exposure to nanosilver found in food‐ and cosmetics‐related consumer products is of public concern because of the lack of information about its safety. In this study, two widely used in vitro cell culture models, human liver HepG2 and colon Caco2 cells, and the flow cytometric micronucleus (FCMN) assay were evaluated as tools for rapid predictive screening of the potential genotoxicity of nanosilver. Recently, we reported the genotoxicity of 20 nm nanosilver using these systems. In the current study presented here, we tested the hypothesis that the nanoparticle size and cell types were critical determinants of its genotoxicity. To test this hypothesis, we used the FCMN assay to evaluate the genotoxic potential of 50 nm nanosilver of the same shape, composition, surface charge and obtained from the same commercial source using the same experimental conditions and in vitro models (HepG2 and Caco2) as previously tested for the 20 nm silver. Results of our study show that up to the concentrations tested in these cultured cell test systems, the smaller (20 nm) nanoparticle is genotoxic to both the cell types by inducing micronucleus (MN). However, the larger (50 nm) nanosilver induces MN only in HepG2 cells, but not in Caco2 cells. Also in this study, we evaluated the contribution of ionic silver to the genotoxic potential of nanosilver using silver acetate as the representative ionic silver. The MN frequencies in HepG2 and Caco2 cells exposed to the ionic silver in the concentration range tested are not statistically significant from the control values except at the top concentrations for both the cell types. Therefore, our results indicate that the ionic silver may not contribute to the MN‐forming ability of nanosilver in HepG2 and Caco2 cells. Also our results suggest that the HepG2 and Caco2 cell cultures and the FCMN assay are useful tools for rapid predictive screening of a genotoxic potential of food‐ and cosmetics‐related chemicals including nanosilver. Published 2016. This article is a U.S. Government work and is in the public domain in the USA. 相似文献
999.
1000.
目的:研究槐耳颗粒对晚期大肠癌化疗患者中医症状及生活质量的影响。方法:将60例符合纳入标准的晚期大肠癌患者,随机分为治疗组和对照组,治疗组30例,采用槐耳颗粒联合化疗,化疗采用FOLFOX4方案;对照组30例,单纯化疗,方案同治疗组。4周期后,分别观察两组患者治疗前后中医症状评分、KPS评分,食欲及体重方面的变化。结果:两组患者在中医症状评分疗效,Kamofsky评分,食欲及体重方面比较差异有统计学意义(P〈0.05)。结论:槐耳颗粒联合化疗可改善晚期大肠癌患者的中医症候及体力状况,提高患者生活质量。 相似文献