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61.
This study investigated the anti-corrosion performance of commercial amino alcohol migratory corrosion inhibitors (MCIs) on concrete that underwent varying degrees of chloride erosion. Electrochemical impedance spectroscopy (EIS), potentiodynamic polarization (PD), scanning electron microscopy, and energy dispersive spectroscopy (SEM-EDS) analyses were performed to study the anti-corrosion performance and mechanism of the MCIs on the steel bars. The results indicated that the corrosion resistance of the steel bars in concrete was significantly improved by coating with the MCIs, and the earlier the specimens were coated with the MCIs, the higher the anti-corrosion efficiency. The anti-corrosion efficiency was 55.35% when the MCIs coating was applied before chloride erosion; however, the anti-corrosion efficiency decreased to 3.40% when the MCIs coating was applied after the ninth drying–wetting cycle. The improvement in corrosion resistance of the steel bar in concrete coated with MCIs was due to the protective MCIs-molecule film that formed on the steel bar surfaces, and the oxidative dissolution of iron at the anode was effectively inhibited by the MCIs coating.  相似文献   
62.
AimThe investigation aims to evaluate the potential effect of Shugan Granule (SGKL) on the gut, brain, and behaviors in rats exposed to chronic restraint stress (CRS).MethodsThe fecal microbiota and metabolite changes were studied in rats exposed to CRS and treated with SGKL (0.1 mg/kg/day). Depressive behaviors of these rats were determined through an open‐field experiment, forced swimming test, sucrose preference, and weighing. Moreover, LPS‐stimulated microglia and CRS‐stimulated rats were treated with SGKL to investigate the regulation between SGKL and the PI3K/Akt/pathway, which is inhibited by LY294002, a PI3K inhibitor.Results(i) SGKL improved the altered behaviors in CRS‐stimulated rats; (ii) SGKL ameliorated the CRS‐induced neuronal degeneration and tangled nerve fiber and also contributed to the recovery of intestinal barrier injury in these rats; (iii) SGKL inhibited the hippocampus elevations of TNF‐α, IL‐1β, and IL‐6 in response to CRS modeling; (iv) based on the principal coordinates analysis (PCoA), SGKL altered α‐diversity indices and shifted β‐diversity in CRS‐stimulated rats; (v) at the genus level, SGKL decreased the CRS‐enhanced abundance of Bacteroides; (vi) Butyricimonas and Candidatus Arthromitus were enriched in SGKL‐treated rats; (vii) altered gut microbiota and metabolites were correlated with behaviors, inflammation, and PI3K/Akt/mTOR pathway; (viii) SGKL increased the LPS‐decreased phosphorylation of the PI3K/Akt/mTOR pathway in microglia and inhibited the LPS‐induced microglial activation; (ix) PI3K/Akt/mTOR pathway inactivation reversed the SGKL effects in CRS rats.ConclusionSGKL targets the PI3K/Akt/mTOR pathway by altering gut microbiota and metabolites, which ameliorates altered behavior and inflammation in the hippocampus.  相似文献   
63.
螺旋CT胆系造影诊断胆管阻塞   总被引:28,自引:0,他引:28  
目的用螺旋CT胆系造影(SCTC)显示胆管狭窄部位和程度,以及扩张胆管的范围。方法阻塞性黄疸患者37例。用30%胆影葡胺40~60ml静脉缓注,延迟25分钟后行螺旋CT扫描并作三维成像。结果胆管显影率为81%,30例显影患者均能显示阻塞部位及扩张胆管,定性诊断正确率为93%。结论SCTC能显示胆管狭窄部位、程度及胆管扩张范围,安全、简单、可靠。能观察肝分泌功能,估价胆汁流通畅程度,是显示胆系阻塞的有效方法  相似文献   
64.
目的:探讨彩色多普勒超声对医源性股动脉假性动脉瘤的诊断及治疗价值。方法对22例经皮股动脉穿刺介入术后触及搏动性肿块的患者采用二维超声、彩色多普勒超声、频谱多普勒超声检查,对声像图进行总结分析,在超声引导下压迫及注射治疗。结果本组22例假性动脉瘤彩色多普勒超声诊断与临床符合率100%(22/22),18例经超声引导下压迫治疗后瘤腔闭合,3例经瘤腔内注射凝血酶治疗取得满意疗效,总治愈率95%(21/22),1例行外科手术治疗。结论彩色多普勒超声是医源性假性动脉瘤首选的诊断及治疗方法。  相似文献   
65.
Objective In order to obtain mature insulin-like growth factor- Ⅱ ( IGF- Ⅱ ), we used Bac-to-Bac baculovirus expression system. Methods Firstly the IGF- Ⅱ cDNA was cloned into a donor plasmid pFastBac1 and the recombinant pFastBac1 was then introduced into competent cells DH 10Bac. Recombinant bacmids were constructed by transposing a mini-Tn7 element from a donor plasmid pFastBac1 to the mini-attTn7 attachment site on the bacmid where the Tn7 transposition functions were provided in trans by a helper plasmid, and then used to transfect Sf9 insect cells to get recombinant baculovirus. The recombinant baculovirus was used to infect insect cells. Results Agarose gel analysis showed that recombinant donor plasmid pFastBac1 was constructed successfully; Agarose gel analysis of PCR products confirmed recombinant bacmid ; SDS-PAGE and Western Blotting showed that a 7KD protein band appeared. Conclusion The mature IGF- Ⅱ with immunogenecity has been expressed and produced by using Bac-to-Bac expression system.  相似文献   
66.
Liposarcomas account for approximately 20% of all adult sarcomas and have limited therapeutic options outside of surgery. Inhibition of ataxia-telangiectasia and Rad3 related protein kinase (ATR) has emerged as a promising chemotherapeutic strategy in various cancers. However, its activation, expression, and function in liposarcoma remain unkown. In this study, we investigated the expression, function, and potential of ATR as a therapeutic target in liposarcoma. Activation and expression of ATR in liposarcoma was analyzed by immunohistochemistry, which was further explored for correlation with patient clinical characteristics. ATR-specific siRNA and the ATR inhibitor VE-822 were applied to determine the effect of ATR inhibition on liposarcoma cell proliferation and anti-apoptotic activity. Migration activity and clonogenicity were examined using wound healing and clonogenic assays. ATR (p-ATR) was overexpressed in 88.1% of the liposarcoma specimens and correlated with shorter overall survival in patients. Knockdown of ATR via specific siRNA or inhibition with VE-822 suppressed liposarcoma cell growth, proliferation, migration, colony-forming ability, and spheroid growth. Importantly, ATR inhibition significantly and synergistically enhanced liposarcoma cell line chemosensitivity to doxorubicin. Our findings support ATR as critical to liposarcoma proliferation and doxorubicin resistance. Therefore, the addition of ATR inhibition to a standard doxorubicin regimen is a potential treatment strategy for liposarcoma.  相似文献   
67.
本文选用小鼠溶血空斑形成试验研究了异佛尔酮二异氰酸酯(IPDI)对Bal/C小鼠脾细胞的作用,选用ANAE染色法观察了IPDI对SD大鼠外周血T细胞的影响,并采用体外培养方法研究了IPDI对人外周血T细胞在PHA刺激下增殖转化的影响。结果表明,IPDI对小鼠脾脏抗体生成细胞的数量和功能均有抑制作用,并呈现出剂量-反应关系;而对细胞免疫反应在大鼠和人均表现为双向作用。  相似文献   
68.
探讨了敦煌医学的文化内涵,提出其特色主要表现在地域性、开放性、多样性、文学性与艺术性,旨在为敦煌医学及其文化的研究提供思路。  相似文献   
69.
In the present experiment,we investigate the effects of orthodontic tooth rotation onneighboring teeth and periodontal tissues.The second maxillary incisors of 16 randomly selecteddogs were subjected to rotation at a magnitude of 100 grams and a moment of 550 g·mm in a du-ration of 3 to 56 days.Then sections were prepared for histological examination.The findings re-vealed that,due to tooth rotation,neighboring teeth were drifted and rotated(82%),and therewere disarrangement and hyalinization of the periodontal ligament(88%),remodeling of the pe-riodontium(86%)and root resorption(32%)were also observed.These results demonstratethat tooth rotation may exert marked effects on neighboring teeth and periodontal tissues,whichmay be of important clinical significance.  相似文献   
70.
Sixteen one-year-old dogs were used in our experiment.We rotated the maxillary secondincisors of the dogs,applying a force of 100g and a moment of 550g·mm.The duration of theexperiment varied from 72h to 8 weeks.Activation was performed once every 2 weeks and the impressions were taken in order to measure the angles of rotation.The results of our experiment showthat the rotation rate of single-rooted tooth in dogs is 3.04/week.The graph shows the form ofgradual stairs.This paper introduces a new specialized experimental apparatus for tooth rotation.The angles of rotation are measured geometrically.  相似文献   
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