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61.
Aluminum alloy is widely used in automobile parts because of its light weight and good process performance. In view of the complex structure of aluminum alloy automobile rear upper control arms, multiple forming processes and the difficulty in quality control, in this paper, we propose a rolling-forging composite process to produce a rear upper control arm. Based on the reasonable volume distribution of the blank by cross-wedge rolling, multi-step forging was carried out. Finite element simulation of thermomechanically coupled multi-step forming was carried out using DEFORM software. Based on a comparison of the traditional process and the proposed rolling-forging composite forming process, we concluded that the rolling-forging composite process can greatly reduce the material cost and the forming force, resulting in superior product performance. The coarse-grain structure of products at different process temperatures was analyzed by a crystal-phase experiment. The results show that the process temperature of the multi-step process, as well as the heat treatment temperature and time have an important influence on the coarse-grain structure of the product. The optimal preheating temperatures for preforging and final forging dies were determined to be 335 °C and 350 °C, respectively; a preheating temperature of 530 °C and a solution time of 45 min resulted in the least coarse-grain surface structure. The research results provide a theoretical basis for improving the multi-step forming quality of automobile rear upper control arms. 相似文献
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目的:探讨多种方法综合治疗口腔及面颈部大面积静脉畸形的临床效果。方法:根据患者的年龄、病变部位、病变大小制订个体化治疗方案,采用多种药物联合注射,结合病变周围环形缝扎、激光、手术等方法综合治疗口腔颌面部大面积静脉畸形134例。结果:134例中治疗效果优79例(58.96%),良45例(33.58%),显效10例(7.46%),差0例。结论:采用多种方法综合治疗口腔颌面部大面积静脉畸形,对提高疗效、改善面部形态、维持局部功能、减少不良反应具有重要意义。 相似文献
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ObjectiveTo present the clinical characteristics of accumulated anterior cruciate ligament (ACL) damage among young male patients undergoing routine exercise, and to evaluate the related risk factors.MethodsA retrospective study involving ACL‐accumulated damage from June 2015 to December 2019 was conducted. Baseline characteristics, such as age, body mass index (BMI), training parameters, and clinical signs, were recorded. The results of the radiologic examinations and related standardized tests were obtained to evaluate the research outcomes. These results were compared using Student''s t‐test or Chi‐square test, and the impact of risk factors on the patient''s injury were analyzed.ResultsA total of 86 men with accumulated ACL damage were included in this study. Exercise pain (86 [100%]), synovitis (80 [93.0%]), and intra‐articular effusion (79 [91.9%]) were the most common clinical symptoms. Loosening of ligaments, decreased tension, mild hyperplasia, and intercondylar fossa effusion were observed using radiography, magnetic resonance imaging, and arthroscopy. Age, BMI, training intensity, length of training, and knee hyperextension were identified as risk factors for accumulated ACL damage.ConclusionThis study suggests that accumulated ACL damage has differentiated clinical symptoms, imaging features, and risk factors compared to common ACL injuries. 相似文献
66.
目的:探究原肌球蛋白3(tropomyosin alpha-3 chain,TPM3)在大鼠胰腺癌细胞中对其侵袭转移能力的影响并初步阐述其可能的分子机制。方法:(1)将70只大鼠随机分为手术组40只[将7,12-二甲基苯并蒽(7,12-dimethyl-1,2-benzanthracene,DMBA]植入大鼠胰腺被膜下后荷包缝合被膜),假手术组15只(只对胰腺进行荷包缝合而后关腹,不置入DMBA),阴性对照组15只(不做任何处理),建立大鼠胰腺癌模型。(2)通过组织免疫组化染色的方法对差异蛋白TPM3进行验证。(3)通过机械分离和酶阶段消化法分离胰腺癌组织的方法获取大鼠胰腺癌细胞,体外传代培养获得纯度较高的细胞后,应用siRNA敲低大鼠胰腺癌细胞中TPM3基因的表达;通过RT-PCR技术检测其沉默效果。(4)通过Transwell实验和平板克隆实验分别对细胞的侵袭、迁移能力及生长增殖能力进行观察。结果:(1)经病理验证模型组有37.83%(14/37)形成胰腺癌,证明大鼠胰腺癌模型建立成功。(2)免疫组化验证胰腺癌组织中TPM3阳性率(92.8%)明显高于正常胰腺组织(6.7%)。(3)RT-PCR结果显示,转染TPM3-siRNA的细胞中TPM3的表达量(0.31±0.02)明显低于其余各组,脂质体组(0.45±0.02),阴性对照组(0.45±0.02),空白对照组(0.43±0.02)(P<0.05),其余各组之间TPM3表达量差异无统计学意义(P >0.05)。(4)转染TPM3-siRNA的细胞其侵袭[(161.63±4.94)个]、迁移能力[(206.87±4.21)个]及生长增殖能力[(51.5±2.327)个]较对照组明显降低[分别为(39.7±1.40)个,(67.27±1.76)个,(5.900±0.767)个](P<0.05)。结论:体外化学合成的TPM3-siRNA可有效的抑制大鼠胰腺细胞TPM3的表达,TPM3表达降低后其侵袭能力、迁移能力及生长增殖能力下降。 相似文献
67.
王翔 《实用中医内科杂志》2010,24(4):19-21
从病因病机(经络论证、脏腑论证)、治疗(汤剂、固定组方、针灸)论述中医治疗重症肌无力。认为,应规范临床科研优选最佳科研方案,建立统一的疗效评定标准。 相似文献
68.
Saier Wang Ying Shi Huiming Xiang Ru Liu Lianghu Su Longjiang Zhang Rongting Ji 《RSC advances》2022,12(35):22760
Biochar has attracted great interest in both CO2 capture and supercapacitor applications due to its unique physicochemical properties and low cost. Fabrication of eco-friendly and cost-effective biochar from high potential biomass Tenebrio molitor feces can not only realize the functional application of waste, but also a potential way of future carbon capture and energy storage technology. In this study, a novel KOH activation waste-fed Tenebrio molitor feces biochar (TMFB) was developed and investigated in terms of CO2 capture and electrochemical performance. When activated at 700 °C for 1 h, the specific surface area of the feces biochar (TMFB-700A) increased significantly from 232.1 to 2081.8 m2 g−1. In addition, well-developed pore distribution facilitates CO2 capture and electrolyte diffusion. TMFB-700A can quickly adsorb a large amount of CO2 (3.05 mol kg−1) with excellent recycling performance. TMFB-700A also exhibited promising electrochemical performance (335.8 F g−1 at 0.5 A g−1) and was used as electrode material in a symmetrical supercapacitor. It provided a high energy density of 33.97 W h kg−1 at a power density of 0.25 kW kg−1 with 90.47% capacitance retention after 10 000 charge–discharge cycles. All the results demonstrated that TMFB could be a potential bifunctional material and provided valuable new insights for Tenebrio molitor feces high-value utilization.Biochar has attracted great interest in both CO2 capture and supercapacitor applications due to its unique physicochemical properties and low cost. 相似文献
69.
Anti‐fibrotic and Anti‐tumorigenic Effects of Rhein,a Natural Anthraquinone Derivative,in Mammalian Stellate and Carcinoma Cells 下载免费PDF全文
Anthraquinone compounds have been recognized to possess antiinflammatory, anti‐fibrotic and anti‐tumour properties and thus applied in human and veterinary therapeutics as active substances of medicinal products. Amongst the anthraquinones isolated from Rheum palmatum, also known as da‐huang, rhein was detected as one of the highest metabolite contents in the bloodstream of mammals. The biological activities of rhein therefore deserve detailed investigation. In this study, we aimed to delineate the mechanism of inhibitory actions of rhein on fibrotic and tumorigenic processes by means of various biochemical assays, such as immunofluorescent staining, real‐time polymerase chain reaction (PCR) and western blotting analyses in rat pancreatic stellate cells (LTC‐14), human pancreatic ductal adenocarcinoma cells (PANC‐1) and human colon carcinoma cells (SW480 and SW620). Our results demonstrated that the application of rhein notably suppressed the mRNA and protein levels of various fibrotic and tumorigenic mediators including alpha‐smooth muscle actin, type I collagen, fibronectin, N‐cadherin and matrix metalloproteinases in the testing mammalian cells. The mechanism of the suppressive actions of rhein was associated with the modulation of the sonic hedgehog and serine‐threonine kinase signalling pathways. In conclusion, we suggest that rhein may serve as a therapeutic or an adjuvant agent in anti‐fibrotic and anti‐tumorigenic approaches. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
70.