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91.
Our previous works have indicated that extracellular ATP is an important prometastasis factor. However, the molecular mechanism involved needs to be further studied. We demonstrated that extracellular ATP treatment could upregulate the expression of connective tissue growth factor (CTGF) in both triple‐negative breast cancer (TNBC) cells and endothelial cells (ECs). Extracellular ATP stimulated the migration of TNBC cells and ECs, and angiogenesis of ECs via the P2Y2––YAP‐CTGF axis. Furthermore, we demonstrated that adenosine triphosphate (ATP) stimulated TNBC cell adhesion to ECs and transmigration through the EC layer via CTGF by upregulation of integrin β1 on TNBC cells and VCAM‐1 on ECs. Both apyrase (ATP‐diphosphohydrolase) and CTGF shRNA treatments could inhibit the metastasis of inoculated tumors to lung and liver in a mouse model, and these treated tumors had fewer blood vessels. Collectively, our data indicated that extracellular ATP promotes tumor angiogenesis and the interactions between TNBC cells and ECs through upregulation of CTGF, thereby stimulating TNBC metastasis. The pleiotropic effects of ATP in angiogenesis and cell adhesion suggest that extracellular ATP or CTGF could be an effective target for TNBC therapy.  相似文献   
92.
目的 探讨早期目标导向活动(EGDM)方案对重症监护病房(ICU)呼吸衰竭机械通气患者睡眠质量及获得性衰弱(ICU-AW)风险的影响。方法 前瞻选取广州市红十字会医院2019年3月~2021年3月96例ICU收治的行机械通气的呼吸衰竭患者,采用随机数表法分为观察组与对照组,各50例。对照组给予ICU常规干预,观察组在对照组基础上实施EGDM方案。观察两组干预3和7 d后医学研究委员会(MRC)评分、Barthel指数(BI)评分及ICU-AW发生率,统计两组机械通气时间、ICU住院时间和总住院时间,测定两组干预前、干预7 d后呼吸力学相关指标[气道阻力(Raw)、肺顺应性(Cl)、内源性呼气末正压(PEEPi)]及睡眠进程参数[睡眠总时间、睡眠潜伏期、快速动眼期(REM)期睡眠时间、觉醒时间、睡眠效率]。结果 干预7 d后观察组MRC评分、ICU-AW发生率与本组干预3 d后比较,差异均无统计学意义(P> 0.05),干预7 d后观察组BI评分显著低于本组干预3 d后,差异有统计学意义(P <0.05),干预7 d后对照组MRC评分、BI评分显著低于本组干预3 d后,ICU...  相似文献   
93.
94.
In this paper, the S32101 duplex stainless steel welded joints were produced by a K-TIG welding system. The weld geometry parameters under different welding speeds were analyzed by combining the morphological characteristics of the keyhole. The microstructure and impact toughness of the base metal and weld metal zone under different welding speeds were studied. The experiment results show that the welding speed has quite an effect on the geometry profile of the weld. In addition, the characteristic parameters of the keyhole can effectively predict the geometry profile of the weld. The test results prove that the microstructure, Σ3 coincidence site lattice grain boundary, and phase boundary of ferrite and austenite have an effect on the impact property of the weld metal zone. When the proportion of the austenite, Σ3 coincidence site lattice grain boundary and random phase boundary increased, the impact property of the weld metal zone also increased.  相似文献   
95.
目的:观察双侧卵巢切除诱导大鼠鼻黏膜上皮细胞凋亡,研究尼尔雌醇、大豆黄酮对此的保护作用。方法:将60只大鼠随机分为4组:健康对照组,卵巢切除组,卵巢切除+尼尔雌醇组,巢巢切除+大豆黄酮组。各组动物分期分3批处死,流式细胞仪检测各组动物鼻中隔黏膜的早期凋亡细胞。结果:双侧卵巢切除后,大鼠鼻黏膜的早期凋亡细胞百分数增高,术后60d达到新的平衡。大豆黄酮、尼尔雌醇干预组与健康组比较,早期凋亡细胞无明显改变。结论:雌激素替代和大豆黄酮可通过减少凋亡细胞而保护鼻黏膜免受雌激素缺乏的损害。  相似文献   
96.
半面痉挛(HFS)病因机理不清,有神经冲动短路、局部癫痛、微血管压迫学说,尚无特效药物治疗。本文报告经鼓室探查术进路行面神经水平段减压术治疗HFS6例,平均随访1.2年,显效4例,复发2例,但程度减轻。5例术中未分离砧镫关节,听力不变。HFS行水平段神经梳理术不复杂,安全有效,是多种手术疗法中可取的一种。作者介绍提高手术效果的几点经验:①鼓室探查术外耳道鼓膜皮瓣比常现大一点,有利于暴露面神经水平段;②镫骨上层结构及砧镫关节是定位面神经骨管的重要标志;③为保持听力,一般不要分离砧镫关节;④面神经水平段骨管近卵圆窗缘较薄,可用细钩针挑开;⑤根据面痉挛病程和痉挛程度的不同,进行不同强度的梳理;⑥对病情顽固者,可行第二次梳理术。  相似文献   
97.
白细胞介素-2对高糖状态下人视网膜色素上皮细胞的影响   总被引:1,自引:0,他引:1  
目的研究白细胞介素-2(IL-2)对高糖状态下人视网膜色素上皮(RPE)细胞的增殖及其分泌和表达血管内皮细胞生长因子(vascular endothelial growth factor,VEGF)的影响。方法MTT自动比色法观察IL-2浓度对高糖状态下RPE细胞增殖的作用;ELISA法测RPE细胞分泌VEGF的变化;免疫组化观察RPE细胞表达VEGF的变化。结果0.1~10μg/L的IL-2均能明显促进高糖状态下RPE细胞的增殖,并能明显提高RPE细胞分泌VEGF的水平及提高VEGF在细胞中的表达。结论高糖状态下,IL-2可明显促进人RPE细胞的增殖并能提高RPE细胞分泌VEGF的水平和提高VEGF在RPE细胞中的表达,IL-2可能在增殖性糖尿病视网膜病变中起一定的作用。  相似文献   
98.
Mammalian cardiomyocytes (CMs) maintain a low capacity for self-renewal in adulthood, therefore the induction of CMs cycle re-entry is an important approach to promote myocardial repair after injury. Recently, photobiomodulation (PBM) has been used to manipulate physiological activities of various tissues and organs by non-invasive means. Here, we demonstrate that conditioned PBM using light-emitting diodes with a wavelength of 630 nm (LED-Red) was capable of promoting the proliferation of neonatal CMs. Further studies showed that low-power LED-Red affected the expression of miR-877-3p and promoted the proliferation of CMs. In contrast, silencing of miR-877-3p partially abolished the pro-proliferative actions of LED-Red irradiation on CMs. Mechanistically, GADD45g was identified as a downstream target gene of miR-877-3p. Conditioned LED-Red irradiation also inhibited the expression of GADD45g in neonatal CMs. Moreover, GADD45g siRNA reversed the positive effect of LED-Red on the proliferation of neonatal CMs. Taken together, conditioned LED-Red irradiation increased miR-877-3p expression and promoted the proliferation of neonatal CMs by targeting GADD45g. This finding provides a new insight into the role of LED-Red irradiation in neonatal CMs biology and suggests its potential application in myocardial injury repair.  相似文献   
99.
Background:Sacubitril/valsartan has been approved for the treatment of heart failure (HF) patients with reduced ejection fraction; since then, it gradually became a new star drug in the therapy of HF. Nevertheless, the effectiveness of sacubitril/valsartan remains under investigation. Thus far, only a few bibliometric studies have systematically analyzed the application of sacubitril/valsartan.Methods:Publications on sacubitril/valsartan were retrieved from the Web of Science Core Collection on April 29, 2021. Data were analyzed using Microsoft Excel 2019 (Redmond, WA), VOS viewer (Redmond, WA), and Cite Space V (Drexel University, Philadelphia, PA).Results:A total of 1309 publications on sacubitril/valsartan published from 1995 to 2021 were retrieved. The number of publications regarding sacubitril/valsartan increased sharply in the last 6 years (2015–2021), and American scholars authored >40% of those publications. Most were published in the European Journal of Heart Failure, the United States was the bellwether with a solid academic reputation in this area. Solomon published the highest number of related articles and was the most frequently cited author. “Heart failure” was the leading research hotspot. The keywords, “inflammation,” “fibrosis,” and “oxidative stress” appeared most recently as research fronts.Conclusions:Research attention should be focused on clinical trial outcomes. Considering its effectiveness in HF, the mechanisms and further applications of sacubitril/valsartan may become research hotspots in the future and should be closely examined.  相似文献   
100.
Objective: To observe the effects of electroacupuncture on hippocampal and cortical apoptosis in a mouse model of cerebral ischemia-reperfusion injury.Methods: Mouse models established by repeated cerebral ischemia-reperfusion,followed by electroacupuncture at Shenshu,Geshu,and Baihui points.The control group mice were intragastrically administered Hydergine.On day 1 and 7 post-treatment,hippocampal and cortical apoptosis was detected by terminal-deoxynucleotidyl transferase mediated dUTP nick-end labeling (TUNEL),and apoptosis images in the hippocampal CA1 zone and cortical area were analyzed.Results: In the model group,apoptotic cells were detected one day after treatment and some cellular fibers were disarrayed.By day 7 post-treatment,there was an increase in the number of apoptotic cells in the hippocampal CA1 region.In addition,there were apoptotic cells in the cortical area,the cortical Jayers were thinner with localized neuronal loss and sieve-like lymphocyte infiltration,as well as glial cell proliferation and visible infarct lesions.However,in the Hydergine and electroacupuncture groups,there was a small number of apoptotic cells.At 7 days post-treatment in the model group,field number,numerical density on area,and surface density were increased.However,in the Hydergine and electroacupuncture groups these parameters were decreased (P<0.01),with a significant difference between the two treatment groups (P<0.01).Conclusion: Electroacupuncture treatment inhibited apoptosis and provided neuroprotection.  相似文献   
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