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1.
目的 系统评价翻转课堂教学模式在物理治疗学教学中的应用效果。方法 计算机检索CENTRAL、MEDLINE、EMBASE、CINAHL Plus、Academic Search Premier、Teacher Reference Center、ERIC以及Education Research,纳入翻转课堂教学模式应用于物理治疗学教学的原始研究。检索时限为建库至2021年6月。由2名研究人员独立完成文献筛选、数据提取、质量评价,对翻转课堂教学模式对比传统教学模式在物理治疗学教学中的效果进行综述。结果与结论 共检索文献1 307篇,最终纳入7篇,包括至少770名学生。发表时间集中在2013年至2019年,研究对象为物理治疗学专业学生,主要结局指标为考试成绩。翻转课堂教学模式总体说来可提高学生的笔试成绩,增强高阶思维能力,得到了学生和教师的积极评价。  相似文献   
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内生菌由细菌、真菌、古菌和原生生物组成,它们生活在植物的活体组织中,具有丰富的次级代谢产物多样性。人参内生菌在人参的生长发育、次级代谢产物的生成和环境适应等方面均有重要的促进作用,对人参的产量和品质有较大影响。随着人们在微生物领域研究的深入,高通量测序技术已经成为研究植物内生菌的重要方法。文章主要从人参内生菌分离与鉴定研究方法、人参内生菌的多样性、人参内生菌及其次级代谢产物的活性、人参内生菌对宿主的影响等4个方面对人参内生菌近年来的研究进展进行讨论,并对其发展方向提出展望,以期为药用植物内生菌研究和品质改良提供新思路、新方法。  相似文献   
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目的探究老年胃癌患者术前血清白细胞介素6 (IL-6)、胃蛋白酶原(PG)Ⅰ、Ⅱ及PG-Ⅰ/Ⅱ比值在患者预后评估中的意义。方法选择2016年1月—2017年1月南通大学附属海安医院收治的101例外科手术治疗的老年胃癌患者为研究对象。收集患者的临床病理资料,检测血清IL-6和PG-Ⅰ/Ⅱ水平。以全因死亡为随访终点,使用Kaplan-Meier曲线明确患者预后与各指标间的关系。结果受试者工作特征曲线提示,IL-6、PG-Ⅰ和PG-Ⅰ/Ⅱ比值在最佳切割值为10.23pg/mL、30.65μg/L和2.44时,可评估患者的预后,而PG-Ⅱ则无法评估患者的预后。与IL-6≤10.23pg/mL组相比,IL-6> 10.23pg/mL组的肿瘤细胞分化更差、TNM分期Ⅲ期比例明显升高。Kaplan-Meier曲线结果表明,IL-6> 10.23pg/mL组的中位生存期显著短于IL-6≤10.23pg/mL组(28个月vs47个月,P<0.001);PG-Ⅰ≤30.65μg/L组的中位生存期显著短于PG-Ⅰ>30.65μg/L组(34个月vs49个月,P=0.008);PG-Ⅰ/Ⅱ≤2.44组的中位生存期显著短于PG-Ⅰ/Ⅱ> 2.44组(29个月vs56个月,P=0.02)。多因素Cox回归分析表明,肿瘤分化程度、TNM分期、IL-6及PG-Ⅰ/Ⅱ比值是影响患者生存率的独立危险因素。结论术前检测IL-6及PG-Ⅰ/Ⅱ比值有助于评估老年胃癌患者的预后。  相似文献   
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Noninvasive imaging of cardiac fibrosis is important for early diagnosis and intervention in chronic heart diseases. Here, we investigated whether noninvasive, contrast agent-free MRI T2-mapping can quantify myocardial fibrosis in preclinical models of aging and pressure overload. Myocardial fibrosis and remodeling were analyzed in two animal models: (i) aging (15-month-old male CF-1 mice vs. young 6- to 8-week-old mice), and (ii) pressure overload (PO; by transverse aortic constriction in 4- to 5-month-old male C57BL/6 mice vs. sham-operated for 14 days). In vivo T2-mapping was performed by acquiring data during the isovolumic and early diastolic phases, with a modified respiratory and ECG-triggered multiecho TurboRARE sequence on a 7-T MRI. Cine MRI provided cardiac morphology and function. A quantitative segmentation method was developed to analyze the in vivo T2-maps of hearts at midventricle, apex, and basal regions. The cardiac fibrosis area was analyzed ex vivo by picro sirius red (PSR) staining. Both aged and pressure-overloaded hearts developed significant myocardial contractile dysfunction, cardiac hypertrophy, and interstitial fibrosis. The aged mice had two phenotypes, fibrotic and mild-fibrotic. Notably, the aged fibrotic subgroup and the PO mice showed a marked decrease in T2 relaxation times (25.3 ± 0.6 in aged vs. 29.9 ± 0.7 ms in young mice, p = 0.002; and 24.3 ± 1.7 in PO vs. 28.7 ± 0.7 ms in shams, p = 0.05). However, no significant difference in T2 was detected between the aged mild-fibrotic subgroup and the young mice. Accordingly, an inverse correlation between myocardial fibrosis percentage (FP) and T2 relaxation time was derived (R2 = 0.98): T2 (ms) = 30.45 – 1.05 × FP. Thus, these results demonstrate a statistical agreement between T2-map–quantified fibrosis and PSR staining in two different clinically relevant animal models. In conclusion, T2-mapping MRI is a promising noninvasive contrast agent-free quantitative technique to characterize myocardial fibrosis.  相似文献   
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ObjectiveSpinal cord stimulation (SCS) is an effective treatment in failed back surgery syndrome (FBSS). We studied the effect of preimplantation opioid use on SCS outcome and the effect of SCS on opioid use during a two-year follow-up period.Materials and methodsThe study cohort included 211 consecutive FBSS patients who underwent an SCS trial from January 1997 to March 2014. Participants were divided into groups, which were as follows: 1) SCS trial only (n = 47), 2) successful SCS (implanted and in use throughout the two-year follow-up period, n = 131), and 3) unsuccessful SCS (implanted but later explanted or revised due to inadequate pain relief, n = 29). Patients who underwent explantation for other reasons (n = 4) were excluded. Opioid purchase data from January 1995 to March 2016 were retrieved from national registries.ResultsHigher preimplantation opioid doses associated with unsuccessful SCS (ROC: AUC = 0.66, p = 0.009), with 35 morphine milligram equivalents (MME)/day as the optimal cutoff value. All opioids were discontinued in 23% of patients with successful SCS, but in none of the patients with unsuccessful SCS (p = 0.004). Strong opioids were discontinued in 39% of patients with successful SCS, but in none of the patients with unsuccessful SCS (p = 0.04). Mean opioid dose escalated from 18 ± 4 MME/day to 36 ± 6 MME/day with successful SCS and from 22 ± 8 MME/day to 82 ± 21 MME/day with unsuccessful SCS (p < 0.001).ConclusionsHigher preimplantation opioid doses were associated with SCS failure, suggesting the need for opioid tapering before implantation. With continuous SCS therapy and no explantation or revision due to inadequate pain relief, 39% of FBSS patients discontinued strong opioids, and 23% discontinued all opioids. This indicates that SCS should be considered before detrimental dose escalation.  相似文献   
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Background and objective: Myocardial infarction (MI) is a common critical disease of the cardiovascular system. The process of MI is often accompanied by the excessive activation of cardiac sympathetic nerves, which leads to arrhythmia. Resiniferatoxin (RTX) is a transient receptor potential vanilloid 1 (TRPV1), involved in the cardiac sympathetic afferent reflex. However, whether RTX can reduce the occurrence of arrhythmia and exert a cardioprotective effect by inhibiting the sympathetic reflex during MI is still unknown. Methods: The left anterior descending artery of cardiac was clamped to construct a model of MI. RTX (50 μg/ml) was used by epicardial application in MI rats. Ventricular electrophysiologic properties were continuously monitored by a body surface ECG. Yrosine hydroxylase (TH) and growth associated protein 43 (GAP43) were detected by Immunofluorescence staining. Connexin43 and transforming growth factor beta receptor 1 (TGF-β1) were detected by western blot. Norepinephrine (NE) and BNP levels in blood and tissue were determined by ELISA. Cardiac function was assessed by echocardiography. Results: The ERP, APD90, QRS, QT and the Tend-Tpeak intervals in MI rats were all prolonged, but decreased after RTX treatment (n = 3, P<0.05). In contrast, the RR interval was shortened in the MI group, but prolonged in the MI+RTX group (n = 3, P<0.05). RTX treatment significantly reduced ventricular arrhythmias after MI. TH- and GAP43-positive nerve densities and TGF-β1, and cx-43 protein expression were up-regulated in the MI group compared to the sham group, and they were decreased in the MI+RTX group compared to the MI group (n = 3, P<0.05). RTX can decrease serum and tissue NE and BNP levels (n = 3, P<0.05). RTX pretreatment significantly decreased heart rate, HW/BW ratio and LVIDS, and increased LVEF andLVFS values (n = 3, P<0.05). Conclusion: RTX improved cardiac dysfunction, ventricular electrophysiologic properties, and sympathetic nerve remodeling in rats with MI by inhibiting the excessive cardiac sympathetic drive.  相似文献   
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PurposeThe purpose of this study was to make a systematic review and meta-analysis to determine the stent diameter (8 mm vs. 10 mm) that conveys better safety and clinical efficacy for transjugular intrahepatic portosystemic shunt (TIPS).Materials and methodsFour databases were used to identify clinical trials published from inception until March 2020. Data were extracted to estimate and compare one-year and three-year overall survivals, hepatic encephalopathy, variceal rebleeding, and shunt dysfunction rates between patients with 8 mm covered stents and those with 10 mm covered stents.ResultsFive eligible studies were selected, which included 489 patients (316 men, 173 women). The 8 mm covered stent group had higher efficacy regarding one-year or three-year overall survival (odds ratio [OR], 2.88; P = 0.003) and (OR, 1.81; P = 0.04) and lower hepatic encephalopathy (OR, 0.69; P = 0.04) compared with 10 mm covered stent group. There were no significant differences in variceal rebleeding rate (OR 0.80; P = 0.67). However, shunt dysfunction was lower in 10 mm covered stent group (OR, 2.26; P = 0.003).ConclusionsOur results suggest that the use of 8 mm covered stents should be preferred to that of 10 mm covered stents for TIPS placement when portal pressure is frequently monitored.  相似文献   
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