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101.
Background:In septic shock cases, tachycardia and a hyperdynamic hemodynamic profile are characteristics of the condition. It has been reported that using beta antagonist esmolol constitutes a form of treatment to reduce heart rate to improve diastolic filling time and elevate cardiac output, which reduces vasopressor support. Still, there are controversial results. Therefore, in this study, the primary objective is to perform a meta-analysis by systematically evaluating the efficiency and security of using esmolol to treat septic shocks.Methods:A systematic literature search for relevant randomized controlled trials that report evaluations on the efficiency and safety of using esmolol to treat septic shock patients from their inception to February 2022 will be conducted in three databases containing publications in Chinese language (WanFang, Chinese BioMedical Literature Database, and China National Knowledge Infrastructure) and four databases containing English language publications (Cochrane Library, PubMed, Web of Science, and EMBASE). The screening of the relevant studies will be performed by a pair of authors independently, and the screening involves examining the title, abstract and full-text stages, data extraction, and bias risk assessment. The results are summarized through the fixed-effects and random-effects models, the respective models will be utilized for data pooling according to the heterogeneity of studies that will be included. Moreover, publication bias is assessed if more than ten studies are considered.Results:The results are a high-quality synthesis of the most recent evidence for esmolol usage in septic shock treatment.Conclusion:Up-to-date evidence will be provided through the results of this systematic review related to assessing the efficacy and safeness of esmolol usage in treating septic shock.Ethics and dissemination:Ethical permissions are not required as prepublished data are used.OSF registration number:DOI 10.17605/OSF.IO/SKEZ7  相似文献   
102.
Background:When it comes to preterm newborns, respiratory distress syndrome (RDS) is the most frequent respiratory condition. Despite the fact that it is well acknowledged that preterm delivery plays a significant role, the causes of lung damage are still not completely understood. In newborns with extremely low birth weight and neonatal RDS, nasal continuous positive airway pressure has been suggested as the first respiratory assistance for spontaneous breathing. In the current research, we aim to carry out a meta-analysis to assess the effectiveness and safety of high-flow nasal cannula (HFNC) and non-invasive continuous positive airway pressure (nCPAP) in patients with neonatal respiratory distress syndrome (NRDS).Methods:We intend to search the following databases: PubMed, EMBASE, Cochrane Library, Wanfang database, China National Knowledge Infrastructure (CNKI), and Google Scholar, starting from their initial publication until February 2022, to identify randomized controlled trials comparing HFNC to nCPAP in patients with NRDS. The suitable papers will be chosen by 2 writers who will work independently of one another. Using the Cochrane updated technique for risk of bias, each included article will be subjected to an independent data extraction process by the 2 writers who will then independently evaluate the risk of bias. Consequently, a third author will be asked to address any discrepancies that may arise between the writers. It will be necessary to pool the data and do a meta-analysis with the help of the RevMan 5.3 software.Results:In this study, the effectiveness and safety of HFNC will be compared with those of nCPAP in patients with NRDS.Conclusion:If the results of this research are confirmed, they may serve as a summary of the most recent data for non-invasive respiratory assistance in NRDS.Ethics and dissemination:The study will require ethical approval.Registration number:DOI 10.17605/OSF.IO/BKSQ5  相似文献   
103.
104.
Lin XB  Zhou NN  Li S  Cai QQ  Xia ZJ  Liao H  Gao Y  Huang HQ 《癌症》2008,27(10):1100-1105
背景与目的:甲氨蝶呤(methotrexate,MTX)在脑脊液中高于最小有效治疗浓度是治疗中枢淋巴瘤的必要条件,目前尚不明确大剂量MTX(high doseMTX,HD-MTX)静脉给药时间对MTX穿透血脑屏障的影响.本研究探索HD-MTX静脉不同给药时间对脑脊液中MTX浓度的影响,以获得更好的中枢淋巴瘤防治效果并尽可能减少MTX外周毒性.方法:34例非霍奇金淋巴瘤患者分别接受MTX 1~3g/m2 6 h持续静脉给药或24 h持续静脉给药,其中17例交替使用两种给药方法;采用高效液相色谱法检测MTX停药0 h、24 h、48 h的MTX血清浓度,及停药0 h后脑脊液中MTX浓度;比较两组血中和脑脊液中MTX浓度以及毒性反应,并对影响MTX浓度的因素进行相关分析.结果:给药结束时6 h给药组的MTX血清浓度显著高于24 h给药组:自身对照结果6 h给药组的脑脊液中MTX浓度为0.70 Ixmol/L,明显高于24 h给药组的0.49 Ixmol/L(校正值,P=0.044).MTX的脑脊液浓度与血清浓度呈正相关,中枢侵犯患者脑脊液MTX浓度显著高于无中枢侵犯的患者.自身对照结果6 h组和24 h组Ⅱ~Ⅳ度粘膜炎的发生率分别15.4%和37.8%.Ⅲ~Ⅳ度骨髓抑制的发生率分别为46.2%和67.6%.结论:在提高MTX的中枢浓度和降低外周毒性方面,HD-MTX 6 h给药方案优于24 h给药方案.  相似文献   
105.
Therapeutic nanoparticles are designed to enhance efficacy, real-time monitoring, targeting accuracy, biocompatibility, biodegradability, safety, and the synergy of diagnosis and treatment of diseases by leveraging the unique physicochemical and biological properties of well-developed bio-nanomaterials. Recently, bio-inspired metal nanoclusters (NCs) consisting of several to roughly dozens of atoms (<2 nm) have attracted increasing research interest, owing to their ultrafine size, tunable fluorescent capability, good biocompatibility, variable metallic composition, and extensive surface bio-functionalization. Hybrid core–shell nanostructures that effectively incorporate unique fluorescent inorganic moieties with various biomolecules, such as proteins (enzymes, antigens, and antibodies), DNA, and specific cells, create fluorescently visualized molecular nanoparticle. The resultant nanoparticles possess combinatorial properties and synergistic efficacy, such as simplicity, active bio-responsiveness, improved applicability, and low cost, for combination therapy, such as accurate targeting, bioimaging, and enhanced therapeutic and biocatalytic effects. In contrast to larger nanoparticles, bio-inspired metal NCs allow rapid renal clearance and better pharmacokinetics in biological systems. Notably, advances in nanoscience, interfacial chemistry, and biotechnologies have further spurred researchers to explore bio-inspired metal NCs for therapeutic purposes. The current review presents a comprehensive and timely overview of various metal NCs for various therapeutic applications, with a special emphasis on the design rationale behind the use of biomolecules/cells as the main scaffolds. In the different hybrid platform, we summarize the current challenges and emerging perspectives, which are expected to offer in-depth insight into the rational design of bio-inspired metal NCs for personalized treatment and clinical translation.Key words: Metal nanoclusters, Biomolecule, Nanoparticles, Hybrid system, Synergistic properties, Fluorescence, Bioprobe, Therapy  相似文献   
106.
The Sn-Ag-Cu (SAC) solder alloys with a low Ag (Ag < 3 wt.%) content have attracted great attention owing to their low cost, increased ability in bulk compliance, and plastic energy dissipation. However, some of their mechanical properties are generally lower than the SAC alloys with a higher Ag content. Adding alloying elements is an effective approach for improving the mechanical properties of the SAC alloys. In this study, the effect of Bi, Sb, and Ti on Sn-1 wt.%Ag-0.5 wt.%Cu (SAC105) solder alloys was investigated. The SAC solders with four compositions: SAC105-1 wt.%Bi, SAC105-1 wt.%Sb, SAC105-1 wt.%Bi-1 wt.%Sb, SAC105-1 wt.%Bi-1 wt.%Sb-0.4 wt.%Ti were prepared. The microstructure and phase compositions were characterized using electron scanning microscopy, and X-ray diffraction. The thermal properties and wettability were also examined. Uniaxial tensile tests and nano-indentation tests were conducted to evaluate the mechanical properties. The results show that adding Bi or Sb could increase the strength of SAC105 alloys mainly due to the solid solution strengthening effect. The creep resistance of SAC105 alloys was also improved with the additions of Bi and Sb. The co-additions of Bi and Sb into SAC105 alloys exhibit an enhanced creep resistance than that calculated by the theoretical calculation. The further addition of Ti into SAC105-1Bi-1Sb alloys demonstrated a much-improved creep resistance, which could be attributed to the synergistic effects of both solid solution strengthening and the precipitation hardening effects.  相似文献   
107.
Cai  Hongke  Chen  Xi  Zhang  Jianbo  Wang  Jijian 《Journal of natural medicines》2018,72(1):252-259
Journal of Natural Medicines - 18β-glycyrrhetinic acid (18β-GA) is a bioactive component of licorice root which exerts pharmacological activities including anti-inflammatory, antiviral,...  相似文献   
108.
109.
To increase the durability and seismic resilience of coastal bridges, a hybrid reinforced concrete (HRC) bridge that incorporates both glass fiber-reinforced polymer (GFRP) bars and steel bars is proposed. The time-dependent seismic performance of the HRC bridge is comprehensively investigated at three levels, namely the material, bridge column and bridge structure levels. First, the decrease of tensile strength of GFRP bars over time is analyzed based on the Arrhenius theory, and corrosion initiation time and performance deterioration of steel bars are determined by Fick’s second law and an empirical formula. Second, an efficient finite element modeling method for aging HRC bridge columns is proposed. Simulation of the compression/tension behavior and the fracture failure of the GFRP bar is described. Hysteretic analysis is further conducted to investigate the time-dependent energy dissipation, ductility, residual displacement, bearing capacity and post-yield stiffness ratio. Meanwhile, comparisons of HRC bridge columns to reinforced concrete (RC) references are provided. Third, the seismic demand and damage evolution of deteriorated HRC bridge structures are investigated through dynamic time-history analysis. The results indicate that the corrosion-resistant GFRP bars contribute to improving the bearing capacity and to reducing the residual displacement of the HRC bridge. With an increase in service time, the seismic damage to the bridge column, abutment and expansion bearing increases, but the damage to fixed bearing decreases. Research results presented herein show that the HRC bridge is a promising alternative structure scheme in the marine environment.  相似文献   
110.
PRK术后角膜上皮下雾状混浊的相关因素分析   总被引:3,自引:0,他引:3  
为探讨准分子激光角膜切削术(photorefractivekeratectomy,PRK)后角膜上皮下雾状混浊(haze)的原因及影响因素,对PRK后6个月时屈光度在-1.00~-18.50D的316例(615只眼)近视眼的haze相关因素进行观察和比较。结果:PRK后6个月时haze发生率为44.7%,1级或以上haze为13.3%。haze的发生率及密度随屈光度增高而增加(P<0.0001),也随切削深度的增加而增加(P<0.0001),术前非接触眼压超过18mmHg者,haze的发生率和密度增加(P<0.005),男性较易发生haze(P=0.0001),与年龄呈负相关(P<0.05)。而角膜厚度、术前戴用接触镜及散光对haze的影响不显著。结论:高度近视(>-6.0D)和过深的切削(>80μm)是引起haze的主要原因。术前眼压偏高、年龄偏低对haze也有明显影响。对PRK治疗高度近视应持审  相似文献   
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