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41.
Sodium-glucose cotransporter-2 inhibitors (SGLT2 inhibitors) are a new type of drug for the treatment of diabetes, and they have been proven to have a good hypoglycemic effect. Several lines of clinical evidence have shown that SGLT2 inhibitors can significantly reduce the risks of atherosclerosis, hospitalization for heart failure, cardiovascular death, and all-cause mortality and delay the progression of chronic kidney disease. Because of the protective effects of SGLT2 inhibitors on the heart and kidney, they are being studied for the treatment of heart failure and chronic kidney disease in patients without diabetes. Therefore, it is necessary for cardiologists, patients with diabetes, and nephrologists to fully understand this type of drug. In this review, we summarize the following three aspects of SGLT2 inhibitors: the recent clinical evidence of their cardiovascular benefits, their mechanisms of action, and their safety.  相似文献   
42.
Helicobacter pylori (H. pylori) is a main risk factor for gastric cancer (GC). Epithelial-mesenchymal transition (EMT) is involved in the development and progression of H. pylori-associated GC. However, the exact molecular mechanism of this process remains unclear. The AKT/GSK3β signaling pathway has been demonstrated to promote EMT in several types of cancer. The present study investigated whether H. pylori infection induced EMT, and promoted the development and metastasis of cancer in the normal gastric mucosa, and whether this process was dependent on AKT activation. The expression levels of the EMT-associated proteins, including E-cadherin and N-cadherin, were determined in 165 gastric mucosal samples of different disease stages by immunohistochemical analysis. The expression levels of E-cadherin, N-cadherin, AKT, phosphorylated (p-)AKT (Ser473), GSK3β and p-GSK3β (Ser9) were further determined in H. pylori-infected Mongolian gerbil gastric tissues and cells co-cultured with H. pylori by immunohistochemical analysis and western blotting. The results indicated that the expression levels of the epithelial marker E-cadherin were decreased, whereas the expression levels of the mesenchymal marker N-cadherin were increased during gastric carcinogenesis. Their expression levels were associated with H. pylori infection. Furthermore, H. pylori infection resulted in downregulation of E-cadherin expression and upregulation of N-cadherin expression in Mongolian gerbils and GES-1 cells. In addition, an investigation of the associated mechanism of action revealed that p-AKT (Ser473) and p-GSK3β (Ser9) were activated in GES-1 cells following co-culture with H. pylori. Furthermore, following pretreatment of the cells with the AKT inhibitor VIII, the expression levels of E-cadherin, N-cadherin, p-AKT and p-GSK3β did not show significant differences between GES-1 cells that were co-cultured with or without H. pylori. The levels of p-AKT and p-GSK3β were increased in H. pylori-infected Mongolian gerbils. In conclusion, the present study demonstrated that H. pylori infection activated AKT and resulted in the phosphorylation and inactivation of GSK3β, which in turn promoted early stage EMT. These effects were AKT-dependent. This mechanism may serve as a prerequisite for GC development.  相似文献   
43.
朱忆  张继春 《护理学杂志》2019,34(22):61-63
目的了解护理人员的科研能力与职业认同现状及其相关性,为采取针对性措施提高护理人员科研能力,增强其职业认同感提供参考。方法采用护理人员科研能力自评量表与护士职业认同评价量表,对350名护理人员进行调查。结果护理人员科研能力及科研实践能力、专业与发现问题能力、沟通协作能力3个维度得分率分别为37.50%、25.00%、50.00%、50.00%,职业认同评价量表总均分为5.52分。护理科研能力与职业认同呈正相关(P0.01)。结论护理人员具有较高的职业认同,其科研能力尚待加强,科研能力与职业认同呈正相关。管理者应注重护理人员科研能力的培养,从而提高其职业认同。  相似文献   
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Chemical exchange saturation transfer (CEST) MRI is sensitive to labile proton concentration and exchange rate, thus allowing measurement of dilute CEST agent and microenvironmental properties. However, CEST measurement depends not only on the CEST agent properties but also on the experimental conditions. Quantitative CEST (qCEST) analysis has been proposed to address the limitation of the commonly used simplistic CEST‐weighted calculation. Recent research has shown that the concomitant direct RF saturation (spillover) effect can be corrected using an inverse CEST ratio calculation. We postulated that a simplified qCEST analysis is feasible with omega plot analysis of the inverse CEST asymmetry calculation. Specifically, simulations showed that the numerically derived labile proton ratio and exchange rate were in good agreement with input values. In addition, the qCEST analysis was confirmed experimentally in a phantom with concurrent variation in CEST agent concentration and pH. Also, we demonstrated that the derived labile proton ratio increased linearly with creatine concentration (P < 0.01) while the pH‐dependent exchange rate followed a dominantly base‐catalyzed exchange relationship (P < 0.01). In summary, our study verified that a simplified qCEST analysis can simultaneously determine labile proton ratio and exchange rate in a relatively complex in vitro CEST system. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
47.
目的研制加强型鼻咽通气道应用于五官科鼻腔手术后的气道管理。方法选取2014年1月至2015年3月行五官科鼻腔手术的患者60例,将其分为A组和B组,各30例。A组作为加强型鼻咽通气道组,术毕在膨胀止血海绵中放置加强型鼻咽通气道保留鼻腔通气;B组作为对照组,术毕采用传统单纯填塞膨胀止血海绵。通过术后24、48 h随访,对两组患者进行疼痛、睡眠质量、口干程度评分,并对其进行对比分析。结果加强型鼻咽通气道具有良好的抗压抗折性;A组患者24、48 h睡眠质量、口干程度评分均明显优于B组,差异均有统计学意义(P<0.05)。结论加强型鼻咽通气道用于五官科鼻腔手术后气道管理可增强气道管理安全性及患者舒适度。  相似文献   
48.
目的对比研究腹腔镜下外生性肾血管平滑肌脂肪瘤"蘑菇状"剜除与标准肾部分切除术的安全性及有效性,为肾血管平滑肌脂肪瘤腹腔镜下"蘑菇状"剜除术术式的建立提供临床依据。 方法选取海南医学院第二附属医院与解放军总医院2018年1月至2019年5月期间,接受腹腔镜手术的肾血管平滑肌脂肪瘤患者53例,其中25例沿肿瘤假包膜行"蘑菇状"剜除术(A组)、28例行肾部分切除术(B组)。比较两组手术患者的肾动脉阻断时间、手术时间、术中出血量、术后24 h血红蛋白、术后eGFR(estimated glomerular filtration rate,估计肾小球率过滤)的变化、术后住院时间和术后肿瘤复发率。 结果53例手术无术中转开放,无死亡病例。肾动脉阻断时间:A组(11.9±2.2)min、B组(21.5±6.5) min(P<0.001)。手术时间:A组(87.9±24.8)min、B组(114.3±38.9) min(P<0.001)。术中出血量:A组20 ml(20~40)ml、B组50 ml(50~100)ml(P<0.001)。术后24 h血红蛋白变化:A组(7.4±4.3) g/L、B组(12.4±8.8) g/L(P=0.013)。术后24 h eGFR变化:A组(6.2±7.2 )ml(min·1.73 m2),B组(12.7±12.8)ml(min·1.73 m2)(P=0.027)。术后6个月eGFR变化:A组(1.5±3.7)ml(min·1.73 m2)、B组(6.5±5.6)ml(min·1.73 m2)(P<0.001)。术后住院时间:A组4.0 d(3~4)d、B组4.5 d(3~6)d(P=0.023)。术后随访两组术后肿瘤均无复发。 结论采用腹腔镜"蘑菇状"剜除术治疗外生性肾血管平滑肌脂肪瘤在肾动脉阻断时间、术中出血量、术后24 h血红蛋白、术后eGFR变化、术后住院时间等方面均优于传统肾部分切除术,两组术后肿瘤均无复发;该方法安全、有效,适于临床推广。  相似文献   
49.
Limb shortening is a problem associated with surgery for osteosarcoma of the lower extremity in adolescents, as the tumors frequently occur near the epiphysis. Herein we report the use of a less invasive stabilization system (LISS) and an intermittent fixation method to preserve the growth function of epiphysis in an 11-year-old patient with an osteosarcoma of the distal femur.The 11-year-old male presented with left knee enlargement and pain for 2 weeks, and magnetic resonance imaging (MRI) and biopsy were consistent with osteosarcoma of the left distal femur. After preoperative chemotherapy, en bloc tumor resection was performed with margins based on MRI findings preserving the epiphyseal growth plate, the tumor cavity was filled with inactivated bone and bone cement, and a LISS was used to stabilize the femur. Aggressive postoperative chemotherapy was given. Approximately 105 weeks after surgery radiography showed that the distal end of the plate had moved superior to the epiphysis along with bone growth. Locking screws were placed in the distal part of the LISS plate to stabilize the re-implanted bone, and external fixation was not needed.The patient was able to walk with the crutches 1 week postoperatively, and bear weight on the extremity 6 weeks postoperatively. At 6 years after surgery, the patient''s height had increased 52 cm, shortening of the affected limb was only 1 cm, and the circumference of the affected limb was 2 cm smaller than that of the contralateral limb. There was no significant discomfort in the affected limb, and there was no gait abnormality. The patient could jump and run, and could participate in sports including basketball and badminton to the same degree as his peers.In summary, the novel method of bone reconstruction and fixation provided good results in a child with an osteosarcoma of the distal femur. This fixation method preserves the osteogenic function of the epiphysis and restored bone integrity simultaneously, and provides good functional recovery.  相似文献   
50.
Resident and inflammatory macrophages are essential effectors of the innate immune system. These cells provide innate immune defenses and regulate tissue and organ homeostasis. In addition to their roles in diseases such as cancer, obesity and osteoarthritis, they play vital roles in tissue repair and disease rehabilitation. Macrophages and other inflammatory cells are recruited to tissue injury sites where they promote changes in the microenvironment. Among the inflammatory cell types, only macrophages have both pro-inflammatory(M1) and anti-inflammatory(M2) actions, and M2 macrophages have four subtypes. The co-action of M1 and M2 subtypes can create a favorable microenvironment, releasing cytokines for damaged tissue repair. In this review, we discuss the activation of macrophages and their roles in severe peripheral nerve injury. We also describe the therapeutic potential of macrophages in nerve tissue engineering treatment and highlight approaches for enhancing M2 cell-mediated nerve repair and regeneration.  相似文献   
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