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991.
课题组按照教学设计、教学实践和教学反思三个步骤,组织实施微信公众平台辅助战场救治课程教学。教学设计重点关注教学内容设置、学习过程展开和学习效果评价三个环节。内容设置突出重点内容和各知识点的关联性;学习过程强调课前传授和课中内化两个步骤;效果评价综合运用多种方法。通过调查、访谈及分析考试成绩表明,这种新的教学方式被实验班学员普遍接受;该班学员三项核心能力有普遍提高;其考试成绩也高于对照班学员。该应用研究为军医大学组织开展微信公众平台辅助其他课程教学,提供了新鲜思路和有益尝试。此外,对于微信公众平台呈现方式不够多元化等问题,课题组认为尚需深入研究和探讨。  相似文献   
992.
目的 建立稳定高表达增殖细胞核抗原(proliferating cell nuclear antigen,PCNA)或突变体PC-NA(mutant PCNA,mPCNA)目的蛋白的宫颈癌细胞系HeLa细胞,观察PCNA在顺铂诱导的DNA损伤修复中的作用.方法 采用显性负突变策略,通过构建重组人PCNA或mPCNA的真核表达质粒pCDNA3.1/V5-His A-PCNA(His-PCNA)和pCDNA31/V5-His A-mPCNA(His-mPCNA),稳定转染到HeLa细胞中,G418筛选建立稳定高表达目的蛋白的HeLa细胞系;Western印迹法检测蛋白的表达情况;MTT法测定顺铂损伤后不同细胞系的细胞存活率.结果 真核表达质粒经酶切、测序分析与实验设计完全一致;稳定建系后,Western印迹结果显示在相应位置可见清楚的目的条带;MTT结果显示稳定高表达突变体PCNA的细胞系与对照组相比,其细胞存活率呈明显下降趋势.结论 成功构建了真核表达质粒His-PCNA和His-mPC-NA;建立了稳定高表达该质粒的HeLa细胞系;稳定高表达突变体PCNA的细胞系对顺铂损伤更敏感.  相似文献   
993.
BackgroundHyperphosphatemia and anemia, which are common complications of chronic kidney disease (CKD), can independently contribute to cardiovascular events. Several previous studies have found that the iron-based phosphate binder, ferric citrate (FC), could be beneficial to both hyperphosphatemia and anemia.MethodsRelevant literature from PUBMED, EMBASE, the Cochrane Central Register of Controlled Trials (CCRCT) and MEDLINE databases were searched up to 21 February 2022, in order to conduct a meta-analysis to investigate the efficacy, safety and economic benefits of ferric citrate treatment in CKD patients with hyperphosphatemia and anemia. The meta-analysis was conducted independently by two reviewers using the RevMan software (version 5.3).ResultsIn total, this study included 16 randomized clinical trials (RCT) involving 1754 participants. The meta-analysis showed that ferric citrate could significantly reduce the serum phosphorus in CKD patients compared to the placebo control groups (MD −1.76 mg/dL, 95% CI (−2.78, −0.75); p = 0.0007). In contrast, the difference between ferric citrate treatment and active controls, such as non-iron-based phosphate binders, sevelamer, calcium carbonate, lanthanum carbonate and sodium ferrous citrate, was not statistically significant (MD − 0.09 mg/dL, 95% CI (−0.35, 0.17); p = 0.51). However, ferric citrate could effectively improve hemoglobin levels when compared to the active drug (MD 0.43 g/dL, 95% CI (0.04, 0.82); p = 0.03) and placebo groups (MD 0.39 g/dL, 95% CI (0.04, 0.73); p = 0.03). According to eight studies, ferric citrate was found to be cost-effective treatment in comparison to control drugs. Most of the adverse events (AE) following ferric citrate treatment were mild at most.ConclusionCollectively, our review suggests that iron-based phosphate binder, ferric citrate is an effective and safe treatment option for CKD patients with hyperphosphatemia and anemia. More importantly, this alternative treatment may also less expensive. Nevertheless, more scientific studies are warranted to validate our findings.  相似文献   
994.
目的研究水蛭提取物对体外培养新生大鼠大脑皮层神经细胞缺氧性坏死的保护作用。方法采用MTT法观察水蛭提取物对体外缺氧培养的神经细胞坏死的影响。结果水蛭提取物在0.5-2mg/ml浓度范围有抗神经细胞缺氧性坏死作用,其神经细胞坏死率明显下降,较凋亡模型组有显著性差异(P〈0.05),且随着浓度增加其抗缺氧性坏死作用随之增大。结论水蛭提取物对体外培养神经细胞缺氧性坏死有明显的保护作用。  相似文献   
995.
Phloretin is one of the apple polyphenols with anticancer activities. Since tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) serves important roles in inducing apoptosis, the present study examined the effect of phloretin on TRAIL-induced apoptosis in colon cancer cells. Treatment with both phloretin and TRAIL markedly suppressed the survival of cancer cells from several colon cancer cell lines compared with that of cells treated with either TRAIL or phloretin. Additionally, decreased numbers of colonies were observed following addition of phloretin and TRAIL. Furthermore, TRAIL- and phloretin-treated HT-29-Luc cells exhibited decreased luciferase activity. Increased apoptosis was observed in phloretin- and TRAIL-treated HT-29-Luc colon cancer cells, accompanying elevated levels of cleaved poly(ADP-ribose) polymerase, and caspase-3, −8 and −9. The expression levels of MCL1 apoptosis regulator BCL2 family member (Mcl-1) were decreased following addition of phloretin in colon cancer cells. In addition, overexpression of Mcl-1 in phloretin- and TRAIL-treated HT-29-Luc cells resulted in increased cell survival. Treatment of HT-29-Luc cells with a combination of cycloheximide (CHX) and phloretin led to a more prominent decrease in Mcl-1 expression compared with that in cells treated with CHX alone, while Mcl-1 expression was recovered by treatment with MG132. Binding of ubiquitin with Mcl-1 was verified using immunoprecipitation. Intraperitoneal injection of both TRAIL and phloretin into tumor xenografts was associated with a decreased tumor volume compared with that following injection with either TRAIL or phloretin. Overall, the present results suggest a synergistic effect of phloretin on TRAIL-induced apoptosis in colon cancer cells.  相似文献   
996.
Nevus sebaceous (NS) is a common congenital hamartoma of the skin composed predominantly of sebaceous glands. Although most NS are benign skin tumors, malignant transformations have been reported. There is still controversy about the lifetime risk of malignant degeneration and precise surgical criteria. This study reports cases of malignant degeneration and suggests a surgical treatment algorithm. The medical records of patients with basal-cell carcinoma (BCC) arising from NS between January 2001 and January 2021 were retrospectively reviewed. Patient demographics including lesion location, and tumor size were investigated. The symptoms, histological findings before and after excision, complications, and recurrence during 2-year follow-up periods were investigated. Ten patients were identified with BCC arising from NS lesions. All patients were female and the mean age was 52.11 years. All patients complained of sudden morphological changes, the most common type being rapid color changes. Two cases had histological findings that showed a miss-match between punch biopsy and excisional biopsy results. No recurrence was detected 2 years after surgeries in any patients. Cases after third stage, especially in over 40 years who report morphologic changes, should undergo total surgical excision as the first approach, with strong suspicion of malignant degeneration.  相似文献   
997.
睡眠呼吸监测技术的研究进展   总被引:1,自引:0,他引:1  
睡眠呼吸监测技术对于睡眠呼吸暂停综合征的预防、发现及治疗起着重要作用.简要介绍用于睡眠呼吸暂停综合征的监测设备分级及应用趋势,分析睡眠呼吸监测技术的特点,对睡眠呼吸监测技术的研究方向和发展现状进行了综述.  相似文献   
998.
息肉状脉络膜血管病变眼底主要表现为出血、渗出、视网膜色素上皮脱离,与渗出型年龄相关性黄斑变性表现较为相似,但二者流行病学特点、病情转归、视力预后及治疗等方面均有较大的不同.息肉状脉络膜血管病变好发于有色人种,位于黄斑部或视盘旁等部位,发病机制尚不明确,眼底检查可有典型的橘红色病变,吲哚青绿血管造影对于息肉状脉络膜血管病变的诊断具有重要意义,显示为异常分支的脉络膜血管网及末梢血管息肉状扩张.临床上息肉状脉络膜血管病变可以采用激光光凝、光动力学治疗、手术及抗血管内皮细胞生长因子等治疗措施.息肉状脉络膜血管病变的自然转归是一个缓解一复发的过程,可长期保存良好的视力,当伴发一些高危因素时,预后较差.  相似文献   
999.
目的:探讨剪切波弹性成像(shear wave elastography,SWE)与细针穿刺洗脱液甲状腺球蛋白(fine-needle aspiration washout thyroglobulin,FNA-Tg)对甲状腺乳头状癌侧颈部淋巴结转移的诊断价值。方法:回顾性分析159例经病理证实为甲状腺乳头状癌(papillary thyroid carcinoma,PTC)的患者资料,对颈部211枚可疑淋巴结进行常规超声、SWE参数平均值(Emean)、FNA-Tg检查,以术后病理结果为金标准,比较各检测方法的诊断效能。结果:(1)SWE Emean转移组[(50.96±27.66) kPa]高于非转移组[(32.20±17.34) kPa],差异有统计学意义(t=8.761,P<0.01)。受试者工作特征(receiver operating characteristic,ROC)曲线分析表明,SWE Emean最佳诊断阈值为40.42 kPa时对PTC颈部淋巴结转移预测价值较高,曲线下面积(area under...  相似文献   
1000.
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