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991.
张焕巧  杨晓萍  赵瑾  陶林 《农垦医学》2007,29(3):172-175
目的:检测不同间质纤维化程度的原发性肾小球肾炎患者肾组织中整合素连接激酶(ILK)的表达,观察ILK与肾间质纤维化程度之间的关系,探讨ILK在肾间质纤维化中可能的作用.方法:选取原发性肾小球肾炎患者肾活检标本88例,根据肾间质纤维化程度分为四组,采用免疫组化方法,检测各组标本ILK的表达,并将ILK的表达与间质纤维化程度和患者血尿β2微球蛋白水平进行相关分析.结果:ILK主要表达于病变肾小管上皮细胞,并且随间质病变的加重,表达量增加,范围增大.肾小管间质中ILK表达量与肾间质纤维化病变程度和患者血尿β2微球蛋白均呈正相关关系.结论:ILK可能参与了肾间质纤维化的形成.  相似文献   
992.
993.
Acoustic metamaterials based on Helmholtz resonance have perfect sound absorption characteristics with the subwavelength size, but the absorption bandwidth is narrow, which limits the practical applications for noise control with broadband. On the basis of the Fabry–Perot resonance principle, a novel sound absorber of the acoustic metamaterial by parallel connection of the multiple spiral chambers (abbreviated as MSC-AM) is proposed and investigated in this research. Through the theoretical modeling, finite element simulation, sample preparation and experimental validation, the effectiveness and practicability of the MSC-AM are verified. Actual sound absorption coefficients of the MSC-AM in the frequency range of 360–680 Hz (with the bandwidth Δf1 = 320 Hz) are larger than 0.8, which exhibit the extraordinarily low-frequency sound absorption performance. Moreover, actual sound absorption coefficients are above 0.5 in the 350–1600 Hz range (with a bandwidth Δf2 = 1250 Hz), which achieve broadband sound absorption in the low–middle frequency range. According to various actual demands, the structural parameters can be adjusted flexibly to realize the customization of sound absorption bandwidth, which provides a novel way to design and improve acoustic metamaterials to reduce the noise with various frequency bands and has promising prospects of application in low-frequency sound absorption.  相似文献   
994.
Aluminum alloy tubes are widely used in various industries because of their excellent performance. Up to now, when the tube is bent, the elastoplastic deformation evolution mechanism of the cross-section has not been clear, and no direct analytical proof has been found. In this paper, based on the bilinear material model assumption, a new mechanical model of tube plane bending deformation is constructed. The analytical model can describe in detail the evolution mechanism of elastic–plastic deformation on the cross-section of the tube after bending deformation, the position of the elastic–plastic boundary, the position of the radius of the strain neutral layer, and the relationship between the bending moment over the section and the bending radius. According to this model, the deformation law of the tube cross-section during bending is elucidated. The results are as follows: (1) the deformation evolution of the cross-section of the bending deformed tube calculated by the analytical model is in good agreement with the finite element model (FEM) of pure bending. (2) By comparing the results of the analytical model with FEM results, and the processing test of the self-designed four-axis free bending forming tube bender, the bending moments are in good agreement. (3) Compared with the bending moments calculated by several other analytical models of tube bending, this model has a relatively small deviation value.  相似文献   
995.
How to treat the iron tailings of mining solid waste with high value is an urgent problem on a global scale. In recent years, the application of iron tailings in the building materials industry has attracted the attention of many scholars. The conversion of iron tailings into green building materials helps achieve carbon neutrality and high-value utilization of solid waste, and promotes sustainable development. Although iron tailings have been extensively studied as supplementary cementitious materials, the performance of concrete is not ideal due to its low activity. In this study, the hybrid supplementary cementitious materials system was prepared by iron tailings, phosphorus slag, and steel slag, and the effects of supplementary cementitious materials type, iron tailings content, iron tailings grinding time, and supplementary cementitious materials content on concrete performance were studied. The compressive properties, iron tailings properties, pore structure, interfacial transition zone, and element distribution of hydration products of concrete were tested by compressive strength tests, X-ray Diffractometer (XRD), X-ray Photoelectron Spectroscopy (XPS), Mercury Intrusion Porosimetry (MIP), Backscattering Electron Tests (BSE), and Energy Dispersive Spectrometer (EDS). The results show that further grinding improves the iron tailings activity. There is a synergistic mechanism between steel slag and phosphorus slag in the composite supplementary cementitious materials, which overcomes the low activity defect of iron tailings and produces concrete with a compressive strength exceeding 40 MPa. The composite supplementary cementitious materials can optimize the interfacial transition zone of the concrete interface and reduce the calcium–silicon ratio of the hydration products. However, it will deteriorate the pore structure of the concrete matrix, cause part of the concrete matrix to be damaged and lead to a loss of compressive strength, and the loss is acceptable. This work broadens the methods of comprehensive utilization of iron tailings and also provides a reference for a more detailed understanding of the properties of iron tailings-based concrete.  相似文献   
996.
In order to improve the corrosion resistance of the automotive AM60B-Mg alloy, a nano-SiO2/MAO composite coating was prepared on the surface of the alloy. The electrochemical properties were studied in an 80 °C corrosion environment using potentiodynamic polarization tests. Local Electrochemical Impedance Spectroscopy (LEIS) was used to study the corrosion mechanisms of coating defect zone. The microstructure and phase of the samples were observed by confocal laser microscopy, scanning electron microscopy (SEM) and X-ray diffraction (XRD). Macroscopic electrochemical test results showed that the impedance of the nano-SiO2/MAO coating was much higher than that of the MAO coating, by about 433 times. Local electrochemical test results showed that the minimum impedance of the nano-SiO2/MAO coating was 1–2 orders of magnitude higher than the maximum impedance of the MAO coating. The defective SiO2/MAO coating still had high corrosion resistance compared to the defective MAO coating. A physical model of local corrosion mechanisms was proposed.  相似文献   
997.
笔者自2002年9月以来,将周围性面神经麻痹分为3期,急性期(发病10天内),恢复期(10天至2月),后遗症期(2月以后)。根据十几年的治疗经验,总结出运用分期针刺配合穴位注射治疗周围性面神经麻痹89例疗效满意,现总结报告如下。1临床资料89例患者均为本院门诊病人,其中男41例,女48例;年龄最小4岁,最大79岁,平均38.4岁;病程最短2天,最长2年。急性期31例,恢复期48例,后遗症期10例。诊断标准:参照《国际针灸交流手册》拟定。(1)以口眼歪斜为主要症状,患侧眼裂扩大,眼睑闭合不全;患侧额纹消失,鼻唇沟变浅,口角、人中沟向健侧歪斜;蹙额、皱眉、示齿、鼓…  相似文献   
998.
BackgroundTo study the influence of pathological responses (PR) after transcatheter arterial chemoembolization (TACE) on incidences of microvascular invasion (MVI) and early recurrence in hepatocellular carcinoma (HCC) patients.MethodsBetween 2013 to 2015, consecutive HCC patients who underwent liver resection with “curative” intent at three hospitals were enrolled in this study. Patients with different areas of PR after preoperative TACE were compared with those without preoperative TACE on the incidences of MVI, early recurrence rates and patterns of recurrence before and after propensity score matching (PSM).ResultsOf 1,970 patients, 737 patients who received preoperative TACE were divided into three groups according to the areas of PR: ≥90% (n=226), 60–90% (n=447), and <60% (n=64). PR ≥90% was an independent protective factor of incidences of MVI [odds ratio (OR), 0.144; 95% confidence interval (CI), 0.082–0.245, P<0.001) and early recurrence (HR, 0.742; 95% CI, 0.561–0.963, P=0.032); while PR<60% was an independent risk factor of incidences of MVI (OR, 6.076; 95% CI, 3.004–11.728, P<0.001) and early recurrence (HR, 1.428; 95% CI, 1.095–1.929; P=0.009). Furthermore, patients with PR <60% were significantly more likely to develop multiple intrahepatic recurrences involving multiple hepatic segments when compared with patients without preoperative TACE.ConclusionsThis study indicated the area of PR after TACE was closely associated with the incidences of MVI and early tumor recurrence. Patients with PR <60% were at significantly higher risks of having more MVI, early and multiple tumor recurrences  相似文献   
999.
1000.
In patients with triple-negative breast cancer (TNBC), high tumour mutation burden and aberrant oncogene expression profiles are some of the causes of poor prognosis. Therefore, it is necessary to identify aberrantly expressed oncogenes, since they have the potential to serve as therapeutic targets. Transient receptor potential channel 5 opposite strand (TRPC5OS) has been previously shown to function as a novel tumour inducer. However, the underlying mechanism of TRPC5OS function in TNBC remain to be elucidated. Therefore, in the present study TRPC5OS expression was first measured in tissue samples of patients with TNBC and a panel of breast cancer cell lines (ZR-75-1, MDA-MB-453, SK-BR-3, JIMT-1, BT474 and HCC1937) by using qRT-PCR and Western blotting. Subsequently, the possible effects of TRPC5OS on MDA-MB-231 cells proliferation were determined using Cell Counting Kit-8 and 5-Ethynyl-2′-deoxyuridine assays after Lentiviral transfection of MDA-MB-231. In addition, potential interaction partners of TRPC5OS were explored using liquid chromatography-mass spectrometry (LC-MS)/MS. Gene expression patterns following TRPC5OS overexpression were also detected in MDA-MB-231 cells by using High-throughput sequencing. Gene Ontology (GO) and Kyoto Encyclopaedia of Genes and Genomes (KEGG) analysis were then used to systematically verify the potential interactions among the TRPC5OS-regulated genes. The potential relationship between TRPC5OS-interacting proteins and gene expression patterns were studied using Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) analysis. TRPC5OS expression was found to be significantly higher in TNBC tumour tissues and breast cancer cell lines compared with luminal tumour tissues and ZR-75-1. In addition, the overexpression of TRPC5OS significantly increased cell proliferation. High-throughput sequencing results revealed that 5,256 genes exhibited differential expression following TRPC5OS overexpression, including 3,269 upregulated genes and 1,987 downregulated genes. GO analysis results indicated that the functions of these differentially expressed genes were enriched in the categories of ‘cell division’ and ‘cell proliferation’ regulation. KEGG analysis showed that the TRPC5OS-regulated genes were associated with processes of ‘homologous recombination’ and ‘TNF signalling pathways’. Subsequently, 17 TRPC5OS-interacting proteins were found using LC-MS/MS and STRING analysis. The most important protein among interacting proteins was ENO1 which was associated with glycolysis and regulated proliferation of cancer. In summary, data from the present study suggest that TRPC5OS overexpression can increase TNBC cell proliferation and ENO1 may be a potential target protein mediated by TRPC5OS. Therefore, TRPC5OS may serve as a novel therapeutic target for TNBC.  相似文献   
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