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61.
<正>普罗布考(probucol),化学名为丙丁酚,化学式为4,4'-[(1-甲基亚乙基)二双]2,6-二(1,1-二甲基乙基)苯酚,于20世纪7 0年代首先于美国上市并应用于临床,以往认为其主要作用是降低血清胆固醇。近年来研究发现,普罗布考除具有降脂作用外,还具有抗动脉粥样硬化(atherosclerosis,AS)、抗氧化应激、保护血管内皮、预防对比  相似文献   
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目的:探讨将粘性弹力绷带与传统"8"字包扎法结合在腋臭术后护理中的应用效果。方法:选取135例行小切口大汗腺切除术治疗的腋臭患者,采用粘性弹力绷带结合传统"8"字加压包扎的方法进行术后换药及护理,分析护理效果。结果:134例患者术后恢复良好,无血肿及血清肿形成,1例患者出现局部皮肤坏死。结论:对于腋臭术后的护理,粘性弹力绷带结合"8"字包扎是一种简单有效的方法。  相似文献   
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Background:The purpose of this meta-analysis was to assess whether a urinary catheter is necessary for all patients in primary total knee arthroplasty (TKA).Methods:PubMed, EMBASE, the Cochrane Library, Web of Science, and China National Knowledge Infrastructure were systematically searched for randomized controlled trials (RCTs). All RCTs were compared with receive either an indwelling urinary catheter or no urinary catheter in TKA. Primary outcomes were urinary retention and urinary tract infection. Secondary outcomes were the length of stay, duration of the surgery, and the first urination time.Results:A total of 6 RCTs involving 1334 patients were included in the meta-analysis. No significant difference between the 2 groups was found in urinary retention (P = .52), length of stay (P = .38), duration of the surgery (P = .55). However, patients with an indwelling catheter were associated with a higher risk of urinary tract infections and longer time for the first urination than patients without indwelling catheters (P = .009 and P = .004).Conclusion:The available evidence indicates that patients without using the indwelling catheters could reduce urinary tract infections and the time for the first urination, without increase in the incidence of urinary retention in primary TKA.Level of Evidence:Level I, therapeutic study.  相似文献   
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目的:分析注射用血栓通中三七从原料到成品全过程的元素迁移规律,以便更好地控制成品中元素杂质。方法:采用ICP-MS法全面分析三七药材、三七总皂苷(中间体)和注射用血栓通中21种元素的含量。结果:21种元素的标准曲线相关系数r均在0. 999以上,回收率在92. 71%~107. 07%之间,RSD均在5%以内。三七药材中铝、铁含量较高,铅、砷、汞、镉、铜符合中华人民共和国药典的相关规定,三七总皂苷(中间体)和注射用血栓通中多数元素均未检出或含量极低。结论:注射用血栓通的提取工艺可有效去除三七中大部分元素,重金属及有害元素也降到较低水平。  相似文献   
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目的 探索当药苷通过兴奋-收缩耦联信号通路对缺血再灌注损伤后心脏收缩/舒张功能的影响。方法 24只健康雄性SD大鼠随机分为正常组、模型组、10 μmol·L-1当药苷给药组与1 μmol·L-1地高辛给药组,并采用Langendorff系统结合左前降支冠状动脉结扎建立缺血再灌注损伤模型(I/R),2,3,5-氯化三苯基四氮唑(TTC)染色检测各组心脏梗死面积,Powerlab生理记录仪检测血流动力学参数,如左心室舒张压(LVDP)、左心室终末舒张压(LVEDP)、左心室终末收缩压(LVESP)、左心室内压最大上升速率(+dp/dtmax)和左心室内压最大下降速率(-dp/dtmax);提取分离乳鼠原代心肌细胞(NRCMs),建立缺氧/复氧(H/R)损伤模型,随机分为正常组、模型组、1 μmol·L-1当药苷给药组和10 μmol·L-1当药苷给药组,多功能成像细胞分析仪和激光共聚焦显微镜测定各组心肌细胞活力、心率、收缩幅度、收缩时程、达峰时程和舒张时程及钙瞬变峰值。根据前期转录组学测序结果及文献调研,利用实时荧光定量聚合酶链式反应(Real-time PCR)检测L型钙通道相关基因(Cacnb2),细胞色素C氧化酶相关基因(Cox6a2),肌钙蛋白(Tnnc1、Tnni3、Tnnt2)、肌动蛋白(Actc1)、肌球蛋白(Myh6、Myl2、Myl4)等兴奋-收缩耦联通路基因的mRNA表达并对差异基因进行聚类分析。结果 与正常组比较,模型组心肌梗死面积显著增加(P<0.01)、LVDP显著降低(P<0.01)、LVEDP显著上升(P<0.01)、LVESP明显下降(P<0.05)、+dp/dtmax有下降趋势和-dp/dtmax上升趋势及心肌细胞活力降低、心率降低、收缩幅度降低、收缩时程升高、达峰时程升高和舒张时程升高(P<0.01),而当药苷可以逆转上述指标(P<0.05)。此外,心肌细胞经H/R损伤后,Cacnb2、Cox6a2、Tnnc1、Tnni3、Tnnt2、Actc1、Myh6、Myl2、Myl4等兴奋-收缩耦联通路的基因表达下降(P<0.05、P<0.01)。而使用当药苷预处理后,可以增强上述基因的表达(P<0.05)。结论 当药苷通过调节兴奋-收缩耦联信号通路,从而调节原代乳鼠心肌细胞内钙离子水平,增强心肌收缩功能,对抗I/R损伤。  相似文献   
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Cyanidin-3-glucoside (C3G) is a well-known natural anthocyanin with antioxidant and anti-inflammatory properties. In this study, we explored the role and action mechanism of C3G in high glucose (HG)-induced damage of human nucleus pulposus cells (HNPCs). Cell viability was assessed by CCK-8 assay. TUNEL assay was performed for detecting apoptotic rate. Western blot was performed to determine the expression levels of cl-caspase-3, caspase-3, Bax, Bim, collagen II, aggrecan, MMP-3, MMP-13, and ADAMTS5. Reactive oxygen species (ROS) generation was analyzed using DCFH-DA staining. The Nrf2 was knocked down or overexpressed in HNPCs through transfection with si-Nrf2 or pcDNA3.0-Nrf2. C3G treatment (12.5, 25, and 50 μM) improved cell viability of HNPCs under HG condition. HG-induced cell apoptosis of HNPCs was attenuated by C3G with decreased apoptotic rate and relative levels of cl-caspase-3/caspase-3, Bax, and Bim. C3G treatment caused significant increase in expression levels of collagen II and aggrecan and decrease in the relative levels of MMP-3, MMP-13, and ADAMTS5. After treatment with C3G, ROS generation in HNPCs was markedly reduced. Treatment with N-acetylcysteine (NAC) reversed HG-induced cell apoptosis and extracellular matrix (ECM) degradation. C3G treatment induced the expression of Nrf2 and HO-1 in HG-induced HNPCs. Moreover, knockdown of Nrf2 reversed the inhibitory effect of C3G on ROS production. Summarily, C3G exerted a protective effect on ROS-mediated cellular damage in HNPCs under HG condition, which was attributed to the induction of the Nrf2/HO-1 signaling pathway.  相似文献   
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BackgroundThe current deep learning diagnosis of breast masses is mainly reflected by the diagnosis of benign and malignant lesions. In China, breast masses are divided into four categories according to the treatment method: inflammatory masses, adenosis, benign tumors, and malignant tumors. These categorizations are important for guiding clinical treatment. In this study, we aimed to develop a convolutional neural network (CNN) for classification of these four breast mass types using ultrasound (US) images.MethodsTaking breast biopsy or pathological examinations as the reference standard, CNNs were used to establish models for the four-way classification of 3623 breast cancer patients from 13 centers. The patients were randomly divided into training and test groups (n = 1810 vs. n = 1813). Separate models were created for two-dimensional (2D) images only, 2D and color Doppler flow imaging (2D-CDFI), and 2D-CDFI and pulsed wave Doppler (2D-CDFI-PW) images. The performance of these three models was compared using sensitivity, specificity, area under receiver operating characteristic curve (AUC), positive (PPV) and negative predictive values (NPV), positive (LR+) and negative likelihood ratios (LR−), and the performance of the 2D model was further compared between masses of different sizes with above statistical indicators, between images from different hospitals with AUC, and with the performance of 37 radiologists.ResultsThe accuracies of the 2D, 2D-CDFI, and 2D-CDFI-PW models on the test set were 87.9%, 89.2%, and 88.7%, respectively. The AUCs for classification of benign tumors, malignant tumors, inflammatory masses, and adenosis were 0.90, 0.91, 0.90, and 0.89, respectively (95% confidence intervals [CIs], 0.87–0.91, 0.89–0.92, 0.87–0.91, and 0.86–0.90). The 2D-CDFI model showed better accuracy (89.2%) on the test set than the 2D (87.9%) and 2D-CDFI-PW (88.7%) models. The 2D model showed accuracy of 81.7% on breast masses ≤1 cm and 82.3% on breast masses >1 cm; there was a significant difference between the two groups (P < 0.001). The accuracy of the CNN classifications for the test set (89.2%) was significantly higher than that of all the radiologists (30%).ConclusionsThe CNN may have high accuracy for classification of US images of breast masses and perform significantly better than human radiologists.Trial registrationChictr.org, ChiCTR1900021375; http://www.chictr.org.cn/showproj.aspx?proj=33139.  相似文献   
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