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991.
目的:探讨在聚乙二醇(polyethyleneglycol,PEG)诱导的小鼠脉络膜新生血管(choroidalneovascularization,CNV)模型中CD146的表达及意义。方法:将60只8周龄雄性C57BL/6J小鼠采用随机数字表法,将小鼠随机分为第5、10和15天组,每组各20只。设定每组小鼠左眼为正常对照眼,右眼为实验眼,采用在视网膜下注射PEG诱导形成脉络膜新生血管模型。造模后摘取各组小鼠眼球,制作视网膜组织切片及HE染色,鉴定CNV模型。通过比较各组视网膜HE染色切片外核层(outernuclearlayer,ONL)厚度,观察PEG的视网膜毒性作用。采用实时荧光定量PCR法检测小鼠神经视网膜和RPE/脉络膜复合体中CD146、血管内皮生长因子(vascularendothelialgrowthfactor,VEGF)、血管内皮生长因子受体2(vascularendothelialgrowthfactorreceptor2,VEGFR2)的mRNA水平变化。免疫组化染色法检测小鼠眼内CD146、VEGF和VEGFR2的表达。结果:HE染色和ONL层厚度比较均证实,视网膜下注射PEG造模成功且模型可靠,视网膜下注射后第5和10天均有CNV形成。实验组小鼠神经视网膜和脉络膜中CD146、VEGF、VEGFR2的mRNA表达水平与对照组相比明显升高,差异有统计学意义(F=30.412,P=0.000;F=84.974,P=0.000;F=117.423,P=0.000;F=918.786,P=0.000;F=319.110,P=0.000;F=113.896,P=0.000)。Person相关性分析提示在视网膜下注射PEG后,小鼠RPE/脉络膜复合体中CD146与VEGF和VEGFR2的表达量呈正相关(r=0.940,P=0.000;r=0.940,P=0.000;r=0.769,P=0.045;r=0.910,P=0.003;r=0.910,P=0.003;r=0.777,P=0.042)。免疫组化染色的结果显示,在造模第10天后,造模组与正常对照组相比较CD146、VEGFR2在神经节细胞层、内核层、外从状层、外核层的阳性表达均有不同程度增强(P=0.000,P=0.000,P=0.000)。结论:CD146伴随着CNV的形成表达上调,且与VEGF的表达量和VEGFR2的表达量呈正相关性,由此推断CD146可能在CNV形成的病理过程中起到至关重要的作用。 相似文献
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目的:评估Salter骨盆截骨联合股骨截骨术治疗TonnisⅡ度发育性髋关节脱位的疗效。方法:采用回顾性病例分析2010年1月至2015年12月期间我院采用Salter骨盆截骨联合股骨截骨术一期手术治疗TonnisⅡ度发育性髋关节脱位患儿28例(33髋),并与单纯Salter截骨术治疗的24例(24髋)进行比较。结果:52例患儿均得到随访,平均26.8个月(12~64个月)。末次随访时,Salter截骨联合股骨截骨术组:髋臼指数(acetabularindex,AI)为18.1°±5.2°;中心边缘角(centeredgeangle,CE角)为36.3°±36.1°;Sharp角为41.4°±4.7°。单纯Salter截骨术组:AI为15.7°±4.8°;CE角为37.8°±11.6°;Sharp角为40.1°±5.0°。Salter截骨联合股骨截骨术组和单纯Salter截骨术组中分别有2髋(2/33)和6髋(6/24)发生股骨头坏死,差异有统计学意义(χ2=4.131,P=0.042)。根据Severin影像学评价标准,Salter截骨联合股骨截骨术组:优15髋、良11髋、可6髋、差1髋,单纯Salter截骨术组:优5髋、良14髋、可5髋、差0髋,差异无统计学意义(Z=-1.277,P=0.202)。根据McKay髋关节功能评价标准,Salter截骨联合股骨截骨术组:优17髋、良11髋、可5髋、差0髋,单纯Salter截骨术组:优13髋、良7髋、可4髋、差0髋,差异无统计学意义(Z=-0.107,P=0.915)。结论:Salter截骨联合股骨截骨是治疗TonnisⅡ度发育性髋关节脱位的有效方法,联合股骨截骨可减少股骨头坏死发生率。 相似文献
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Yu LIU Xing WANG Zi-Ying CHEN Wen-Li ZHANG Lin GUO Yong-Quan SUN Hong-Zhan CUI Ji-Qiang BU Jian-Hui CAI 《老年心脏病学杂志》2021,18(6):449-461
BACKGROUNDSevere bleeding following cardiac surgery remains a troublesome complication, but to date, there is a lack of comprehensive predictive models for the risk of severe bleeding following off-pump coronary artery bypass grafting (OPCABG). This study aims to analyze relevant indicators of severe bleeding after isolated OPCABG and establish a corresponding risk assessment model.METHODSThe clinical data of 584 patients who underwent OPCABG from January 2018 to April 2020 were retrospectively analyzed. We gathered the preoperative baseline data and postoperative data immediately after intensive care unit admission and used multifactor logistic regression to screen the potential predictors of severe bleeding, upon which we established a predictive model. Using the consistency index and calibration curve, decision curve, and clinical impact curve analysis, we evaluated the performance of the model.RESULTSThis study is the first to establish a risk assessment and prediction model for severe bleeding following isolated OPCABG. Eight independent risk factors were identified: male sex, aspirin/clopidogrel withdrawal time, platelet count, fibrinogen level, C-reactive protein, serum creatinine, and total bilirubin. Among the 483 patients in the training group, 138 patients (28.6%) had severe bleeding; among the 101 patients in the verification group, 25 patients (24.8%) had severe bleeding. Receiver operating characteristic (ROC) curve analysis for the internal training group revealed a convincing performance with a concordance index (C-index) of 0.859, while the area under the ROC curve for the external validation data was 0.807. Decision curve analysis showed that the model was useful for both groups.CONCLUSIONSAlthough there are some limitations, the model can effectively predict the probability of severe bleeding following isolated OPCABG and is therefore worthy of further exploration and verification.Currently, coronary heart disease (CHD) remains a major threat to public health worldwide. Coronary artery bypass grafting (CABG) is considered to be the first choice for the treatment of CHD, especially for complex lesions.[1] To recover the blood flow of the distal coronary artery and achieve complete revascularization of the myocardium, an autologous artery or vein segment is transplanted to the distal segment of the coronary artery demonstrating the primary stenosis. Perioperative bleeding is a common complication of CABG.[2,3] Approximately 15% to 20% of patients consume more than 80% of the blood products used for cardiac surgery.[4] Excessive perioperative bleeding not only escalates the need for blood transfusion but also leads to reoperation and mortality,[5–9] and an increase in the incidence of recurrent myocardial infarction (MI) and stroke.[10]Excessive bleeding is usually associated with a variety of factors. The factors that may affect the haemostatic mechanism include the patient’s individual characteristics (inflammatory conditions, platelet count and dysfunction, fibrinogen level, and coagulation factor abnormalities, etc.) and surgical factors (operation mode, use of cardiopulmonary bypass, etc.). In addition, the preoperative use of aspirin, clopidogrel, and other drugs in patients with CHD can affect haemostatic function and may increase postoperative bleeding.[11,12] It is of great importance to predict the risk of postoperative excessive bleeding and blood transfusion and actively take appropriate preventive and therapeutic measures. However, to date, no biomarker has been able to accurately identify patients at high risk of bleeding. In recent years, many experimental studies have investigated the possible related indicators of excessive bleeding and blood transfusion after cardiac surgery, such as platelet count, fibrinogen level, coagulation factors, and antiplatelet drugs, but none of them has been shown to predict bleeding and blood transfusion after cardiac surgery.[13,14] A single indicator may not be sufficient to predict an increase in bleeding risk. In addition, due to differences in research schemes, sample sizes, and enrolled research subjects, some research designs have obvious confounding factors, so no consistent conclusion has yet been reached. To help clinicians effectively predict the risk of severe bleeding and blood transfusion in patients undergoing off-pump coronary artery bypass grafting (OPCABG) for the first time and rapidly identify high-risk patients at the early stage, we carried out this study. Through systematic retrospective screening of clinical characteristics and routine examination indexes of patients, a diagnostic model was constructed and verified. This model allows doctors to make clinical decisions conveniently, and it can also be used as a tool to communicate with patients or their family members. 相似文献
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探究对激素抵抗特应性皮炎/湿疹患者应用莫匹罗星联合糖皮质激素治疗的效果。方法 选取常州市皮肤病专科医院2020年8月-2021年4月收治的65例激素抵抗特应性皮炎/湿疹患者为研究对象,随机分为对照组(n =32)和研究组(n =33)。对照组予以单一糖皮质激素治疗,研究组予以莫匹罗星联合糖皮质激素治疗,比较两组止痒所需时间、皮损消退时间、临床疗效及并发症发生情况。结果 研究组止痒时间、皮损消退时间均短于对照组,差异有统计学意义(P <0.05);研究组治疗总有效率为96.97%,高于对照组的81.25%,差异有统计学意义(P <0.05);研究组不良反应发生率为15.15%,高于对照组的12.50%,但差异无统计学意义(P >0.05)。结论 对激素抵抗特应性皮炎/湿疹患者应用莫匹罗星联合糖皮质激素治疗的效果良好,可有效改善患者的临床症状,加速皮肤破损消退和止痒,有利于提升患者的躯体舒适度,加快康复进程,且不良反应发生几率较低,治疗安全性较高。 相似文献
999.
探讨PBL教学法在临床口腔修复教学中的应用。方法 选取昆明医科大学海源学院2020级口腔医学本科一大班和二大班学生为研究对象,将一大班学生(105名)纳入对照组,二大班学生(105名)纳入观察组。对照组运用传统教学,观察组运用PBL教学,比较两组理论考核结果、实操考核结果以及教学满意度。结果 观察组第一、二学期理论考核成绩均高于对照组,差异有统计学意义(P <0.05);观察组第一、二学期实操考核成绩均高于对照组,差异有统计学意义(P<0.05);观察组各方面教学满意度评分均高于对照组,差异有统计学意义(P <0.05)。结论 PBL教学法是一种科学高效的教学模式,可有效提高学生教学成绩,增强学生满意度。 相似文献
1000.
目的 观察加味补中益气汤联合戊酸雌二醇/雌二醇环丙孕酮片治疗女性肾阴虚肝郁型更年期综合征的临床疗效及对病人血清促卵泡激素(FSH)、黄体生成激素(LH)表达的影响。方法 按随机数字表法将2019年4月至2021年1月唐山市人民医院收治的198例女性肾阴虚肝郁型更年期综合征病人分入观察组与对照组(各99例)。对照组给予戊酸雌二醇/雌二醇环丙孕酮片治疗,观察组在对照组治疗基础上联合加味补中益气汤治疗。比较两组病人临床疗效、中医证候评分,应用女性绝经期自测表(Kupperman改良评分)评估病人治疗前后临床症状改善情况,检测血清FSH、LH水平及不良反应情况。结果 治疗后,与对照组(70.70%)相比,观察组总有效率(90.90%)更高(P<0.05)。治疗后两组月经紊乱、潮热汗出、急躁易怒、阴道干涩、腰膝酸软、舌质暗红苔薄等各项中医证候评分均降低,且观察组低于对照组(P<0.05)。治疗后两组Kupperman积分均降低,且观察组低于对照组(P<0.05);治疗后两组血清FSH、LH水平降低,雌二醇(E2)水平升高,且观察组血清FSH、LH水平低于对... 相似文献