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51.
In this paper, the electrochemical corrosion behavior of X70 steel in saline soil under capillary water was simulated by a Geo-experts one-dimensional soil column instrument. A volumetric water content sensor and conductivity test were used to study the migration mechanism of water and salt (sodium chloride) under the capillary water. The electrochemical corrosion behavior of the X70 steel in the corrosion system was analyzed by electrochemical testing as well as the macroscopic and microscopic corrosion morphology of the steel. The test results showed that the corrosion behavior of X70 steel was significantly influenced by the rise of capillary water. In particular, the wetting front during the capillary water rise meant that the X70 steel was located at the three-phase solid/liquid/gas interface at a certain location, which worsened its corrosion behavior. In addition, after the capillary water was stabilized, the salts were transported with the capillary water to the top of the soil column. This resulted in the highest salt content in the soil environment and the most severe corrosion of the X70 steel at this location.  相似文献   
52.
ContextSchisandra chinensis (Turcz.) Baill. (Magnoliaceae) essential oil (SCEO) composition is rich in lignans that are believed to perform protective effects in the liver.ObjectiveThis study investigates the effects of SCEO in the treatment of acetaminophen (APAP)-induced liver injury in mice.Materials and methodsC57BL/6 mice (n = 56) were randomly divided into seven groups: normal; APAP (300 mg/kg); APAP plus bicyclol (200 mg/kg); APAP plus SCEO (0.25, 0.5, 1, 2 g/kg). Serum biochemical parameters for liver function, inflammatory factors, and antioxidant activities were determined. The protein expression levels of Nrf2, GCLC, GCLM, HO-1, p62, and LC3 were assessed by western blotting. Nrf2, GCLC, HO-1, p62, and LC3 mRNA were detected by real-time PCR.ResultsCompared to APAP overdose, SCEO (2 g/kg) pre-treatment reduced the serum levels of AST (79.4%), ALT (84.6%), TNF-α (57.3%), and IL-6 (53.0%). In addition, SCEO (2 g/kg) markedly suppressed cytochrome P450 2E1 (CYP2E1) (15.4%) and attenuated the exhaustion of GSH (43.6%) and SOD (16.8%), and the accumulation of MDA (22.6%) in the liver, to inhibit the occurrence of oxidative stress. Moreover, hepatic tissues from our experiment revealed that SCEO pre-treatment mitigated liver injury caused by oxidative stress by increasing Nrf2, HO-1, and GCL. Additionally, SCEO activated autophagy, which upregulated hepatic LC3-II and decreased p62 in APAP overdose mice (p < 0.05).Discussion and conclusionsOur evidence demonstrated that SCEO protects hepatocytes from APAP-induced liver injury in vivo and the findings will provide a reliable theoretical basis for developing novel therapeutics.  相似文献   
53.
For the Honghe Bridge project located in Yunnan Province, Southwest China, a steel/ultrahigh-performance concrete (UHPC) composite deck is used in the suspension bridge with a 700 m main span, and the steel stud connectors are used in the 50 mm–thick UHPC layer. To investigate the shrinkage behavior of UHPC and the relevant influence, the in situ time-dependent strain is measured continuously, and within the 20-day curing time, the material behavior is summarized based on test results. This paper proposes a prediction model for UHPC shrinkage which is refined from the widely used B3 model for normal concrete material, and the parameter values are modified and optimized by experimental comparison. Combining the numerical model and the finite element analysis model of the composite deck, the detailed mechanical state in structural parts is studied. For the practical construction, the simulation results indicate that the small thickness of UHPC above the stud and weak bond strength can influence the eventual structural performance greatly. In the discussion of stress distribution at different locations of the deck, the potential crack on the edge and the corner of the UHPC–steel interface and the mechanical damage on the stud connector around are also indicated.  相似文献   
54.
本研究采用卵蛋白等敏大鼠哮喘模型,观察正常组、哮喘和中药治疗组大鼠血清中总IgE、白细胞介素-4和γ-干扰素的含量变化。结果表明:哮喘大鼠血清总LgE水平、IL-4含量明显增加(P〈0.01),血清中IFN-γ含量明显降低(P〈0.01),而补脾益气方药可显著降低哮喘大鼠IgE水平及IL-4含量(P〈0.01),提高IFN-γ的含量(P〈0.01)。  相似文献   
55.
Purpose  The aim of the study was to evaluate the association of CYP1A1 and CYP1B1 polymorphisms with uterine leiomyoma in Chinese women. Methods  We investigated 100 women with clinically diagnosed uterine leiomyoma and 110 healthy normal subjects from Chinese women. The genetic distribution of two CYP1A1 polymorphisms at MspI, Ile462Val and four CYP1B1 polymorphisms at Arg48Gly, Ala119Ser, Leu432Val, Asp449Asp were analyzed by polymerase chain reaction–restriction fragment length polymorphism and DNA sequencing method. Results  All the SNPs showed polymorphisms in Chinese women. The genotype A/G and the allele G on Ile462Val was significantly different between uterine leiomyoma patients and controls (P < 0.05). Conclusion  These results suggest that the genotype of CYP1A1 Ile462Val was associated with the increased risk of uterine leiomyomas in Chinese women. Capsule This is the first report that demonstrates the polymorphism at Ile462Val of CYP1A1 to be associated with uterine leiomyoma in Chinese women.  相似文献   
56.
目的 评估临床采用氟尿嘧啶类药物联合奥沙利铂治疗晚期转移性小肠癌的临床效果及安全性.方法 回顾性分析近6年来于本院接受化学治疗的89例晚期小肠癌患者的一般资料,按照治疗方法的不同进行等均分组,其中45例患者采取FOLFOX(奥沙利铂、亚叶酸钙、氟尿嘧啶)治疗方案,纳入对照组,另外44名患者采取XELOX(奥沙利铂联合卡培他滨)方案,作为观察组.观察两组临床效果以及用药不良反应,并在随访过程中观察两组中位疾病进展时间.结果 观察组总有效率优于对照组(61.36%比55.55%),但组间差异无统计学意义(P>0.05);观察组毒副反应发生率高于对照组(36.3%比31.1%),但差异无统计学意义(P>0.05).结论 采用氟尿嘧啶类药物联合奥沙利铂治疗晚期转移性小肠癌安全有效,毒副反应可耐受,可作为不可手术切除或转移性小肠癌的一线化疗选择,但仍需要大量数据样本做进一步研究证实.  相似文献   
57.
《傅青主女科》学术特色体现在以下四方面:①别出心裁,补中寓散治带下;②匠心独运,升降结合调月事;③运筹帷幄,养血保精求子嗣;④注重二天,健脾固肾愈胎病。  相似文献   
58.
BackgroundTo assess the temporal changes in the characteristics of ischemic stroke drug clinical trials conducted in mainland China in 2005–2021.MethodsA statistical analysis of registered clinical trials on ischemic stroke was performed using the platform of the Center for Drug Evaluation of China National Medical Products Administration, the Chinese Clinical Trial Registry, and ClinicalTrials.gov websites.ResultsFrom January 1, 2005 to August 1, 2021, a total of 384 registered drug clinical trials on ischemic stroke were identified in mainland China. Over time, the number of trials gradually increased each year, with a significant growth in 2014, from 16 in 2013 to 42 in 2014. Phase IV trials (31.8%) accounted for the majority, followed by phase II (16.4%), phase I (10.9%), and phase III (8.6%). In terms of sponsorship, the proportion of investigator‐initiated trials (IITs) (60.7%) was higher than industry‐sponsored trials (ISTs) (39.3%). Additionally, trials involving traditional Chinese medicines (TCMs) (36.2%) accounted for the largest proportion, followed by trials involving antithrombotic therapy (19.5%) and cerebral protection agents (16.7%). Furthermore, over the past 17 years, the number of leading drug clinical trial units for ischemic stroke in mainland China has continuously increased. The leading principal units from Beijing, Shanghai, Guangdong, Jiangsu, and Liaoning accounted for the majority of the trials (67.4%).ConclusionIn the past 17 years, great progress has been made in the research and development (R&D) of drugs and clinical trials for ischemic stroke in mainland China. The most extensive progress was observed in TCMs, antithrombotic therapy, and cerebral protection agents. More clinical trials are needed to confirm whether the newly developed drugs can improve the clinical efficacy of ischemic stroke. Simultaneously, more pharmaceutical R&D efforts of innovative drugs are warranted.  相似文献   
59.
60.
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   
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