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71.
医学教育改革更多的是热衷于授课形式和方法的改革,而忽视了真正能够渗透到教学各方面的教学理念的改革。结合对生理学教学目标的反思和“岗位胜任力”培养的需求,将生理学教学的核心理念总结为四个方面:“三观”要正,帮助学生树立平衡观、辩证观和整体观;“三基”要牢,培养学生掌握基本的知识架构体系、基本的知识获取能力、基本的操作技能;重视学以致用和强化人文素养。上述核心理念在教学实践中得到学生的广泛认可,临床医学专业学生对核心理念的评价明显高于护理专业。下一步教学改革的方向是在教学理念的指导下如何细化授课内容,以适应专业设置越来越细化的现状。  相似文献   
72.
Pancreatic ductal adenocarcinoma (PDAC) remains a leading cause of cancer-related death due to the failure of traditional therapies. In the present study, we attempted to construct a lncRNA-miRNA-mRNA network which may modulate PDAC cell proliferation and Gemcitabine-induced cell apoptosis starting from CDK14, a new member of the CDK family and an oncogene in many cancers. Based on TCGA data, a significant positive correlation was observed between lncRNA MSC-AS1 and CDK14. Moreover, MSC-AS1 expression was upregulated in PDAC tissues. Higher MSC-AS1 expression was correlated with poorer prognosis in patients with PDAC. MSC-AS1 knockdown in Panc-1 and BxPC-3 cells significantly inhibited the cell proliferation. Moreover, miR-29b-3p, which has been reported to act as a tumor suppressor, was predicted to bind to both MSC-AS1 and CDK14. Contrary to MSC-AS1, higher miR-29b-3p expression was correlated to better prognosis in patients with PDAC. In both PDAC cell lines, miR-29b-3p negatively regulated MSC-AS1 and CDK14. As confirmed using luciferase reporter gene and RIP assays, MSC-AS1 served as a ceRNA for miR-29b-3p to counteract miR-29b-mediated CDK14 repression. MSC-AS1 knockdown inhibited CDK14 protein levels and PDAC proliferation and enhanced gemcitabine-induced cell death and apoptosis while miR-29b-3p inhibition exerted an opposing effect; the effect of MSC-AS1 knockdown was partially attenuated by miR-29b-3p inhibition. Taken together, we demonstrated that MSC-AS1/miR-29b-3p axis modulates the cell proliferation and GEM-induced cell apoptosis in PDAC cell lines through CDK14. We provided a novel experimental basis for PDAC treatment from the perspective of lncRNA-miRNA-mRNA network.  相似文献   
73.
目的 制备吸附重组戊型肝炎病毒(hepatitis E virus,HEV)P179抗原的海藻酸钠/壳聚糖微球混悬制剂,并观察其免疫效果。方法 乳化法制备海藻酸钠/壳聚糖微球,采用不同海藻酸钠浓度、混合乳化剂添加量、混合乳化剂亲水亲油平衡值设计正交试验,确定最佳制备工艺参数。将重组HEV P179抗原吸附在最佳工艺制备的微球表面,制备吸附重组HEV P179的海藻酸钠/壳聚糖微球混悬制剂,皮下多点免疫BALB/c小鼠,测定其诱导小鼠产生特异性IgG抗体的能力,与同剂量含弗氏佐剂的重组HEV P179免疫制剂对比。结果 经正交试验确定乳化最佳工艺参数为:海藻酸钠质量分数1%、混合乳化剂体积分数2%,混合乳化剂亲水亲油平衡值4。制备的微球平均粒径为6.73 μm(分布范围3.90~9.10 μm,方差1.78 μm),形态较为均一,透射电镜观察结果与双层球体及内部疏松多孔的微球结构特点相符。用此条件制备抗原质量浓度为500 μg/ml的混悬制剂,微球对抗原的吸附率为90.64%。免疫效果观察试验结果表明,皮下多点免疫试验中微球制剂诱导特异性IgG抗体的能力优于含弗氏佐剂抗原。结论 成功制备了吸附重组HEV P179的海藻酸钠/壳聚糖微球混悬制剂,且诱导产生特异性IgG抗体的能力优于含弗氏佐剂抗原,为其在新型实验动物超敏制剂中的应用奠定了基础。  相似文献   
74.
Vascular calcification is prevalent in patients with chronic kidney disease (CKD) and a major risk factor of cardiovascular disease. Vascular calcification is now recognised as a biological process similar to bone formation involving osteogenic differentiation of vascular smooth muscle cells (VSMCs). Cell division cycle 42 (CDC42), a Rac1 family member GTPase, is essential for cartilage development during endochondral bone formation. However, whether CDC42 affects osteogenic differentiation of VSMCs and vascular calcification remains unknown. In the present study, we observed a significant increase in the expression of CDC42 both in rat VSMCs and in calcified arteries during vascular calcification. Alizarin red staining and calcium content assay revealed that adenovirus-mediated CDC42 overexpression led to an apparent VSMC calcification in the presence of calcifying medium, accompanied with up-regulation of bone-related molecules including RUNX2 and BMP2. By contrast, inhibition of CDC42 by ML141 significantly blocked calcification of VSMCs in vitro and aortic rings ex vivo. Moreover, ML141 markedly attenuated vascular calcification in rats with CKD. Furthermore, pharmacological inhibition of AKT signal was shown to block CDC42-induced VSMC calcification. These findings demonstrate for the first time that CDC42 contributes to vascular calcification through a mechanism involving AKT signalling; this uncovered a new function of CDC42 in regulating vascular calcification. This may provide a potential therapeutic target for the treatment of vascular calcification in the context of CKD. © 2019 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.  相似文献   
75.
目的 探讨自主学习结合情景模拟教学法在医学生技能培训中的应用效果和意义。方法 选取2012级的60 名医学生进行研究,随机分为试验组和对照组,每组各30 人,培训前对两组学员进行考核,成绩无统计学差异。对照组采用LBL+ 床旁带教的教学方法,试验组采用自主学习结合情景模拟教学方法进行技能培训。两组学生均培训2 个月后进行考核,对考试成绩进行分析比较。考核结束后进行问卷调查,对培训满意度进行调研。结果 试验组的技能考核成绩明显高于对照组,具有统计学意义(P < 0.05);试验组的理论成绩高于对照组,但不具有统计学意义(P > 0.05);试验组对培训的满意度(90%)明显高于对照组(77.8%),具有统计学意义(P < 0.05)。结论 采用自主学习结合情景模拟教学方法对医学生进行培训能明显提高临床技能培训效果,提高医学生培训满意度,是一种较好的实践技能教学方法。  相似文献   
76.
BACKGROUNDGuillain-Barré syndrome (GBS) is a rare disorder that typically presents with ascending weakness, pain, paraesthesias, and numbness, which mimic the findings in lumbar spinal stenosis. Here, we report a case of severe lumbar spinal stenosis combined with GBS.CASE SUMMARYA 70-year-old man with a history of lumbar spinal stenosis presented to our emergency department with severe lower back pain and lower extremity numbness. Magnetic resonance imaging confirmed the diagnosis of severe lumbar spinal stenosis. However, his symptoms did not improve postoperatively and he developed dysphagia and upper extremity numbness. An electromyogram was performed. Based on his symptoms, physical examination, and electromyogram, he was diagnosed with GBS. After 5 d of intravenous immunoglobulin (0.4 g/kg/d for 5 d) therapy, he gained 4/5 of strength in his upper and lower extremities and denied paraesthesias. He had regained 5/5 of strength in his extremities when he was discharged and had no symptoms during follow-up.CONCLUSIONGBS should be considered in the differential diagnosis of spinal disorder, even though magnetic resonance imaging shows severe lumbar spinal stenosis. This case highlights the importance of a careful diagnosis when a patient has a history of a disease and comes to the hospital with the same or similar symptoms.  相似文献   
77.
Skin injury can trigger formation of new lesions in psoriasis (Koebner phenomenon). The mechanisms through which injury exacerbates psoriasis are unclear. During wound repair, epidermal keratinocytes are activated and produce abundant IL‐36γ, further promoting the skin inflammation. IL‐17A is the cornerstone cytokine in the pathogenesis of psoriasis. We sought to investigate the effects of IL‐17A on injury‐induced keratinocyte activation and IL‐36γ production. Here, we demonstrated that dsRNA released from necrotic keratinocytes induced the expression of IL‐36γ. Silencing of TLR3 by siRNA decreased the IL‐36γ induction by necrotic keratinocyte supernatant. Co‐stimulation with dsRNA and IL‐17A synergistically increased the expression of IL‐36γ and other proinflammatory mediators (CCL20, CXCL8, DEFB4 and LCN2) in keratinocytes. The synergistic effects were not dependent on TLR3 upregulation, TNF receptor signalling and mRNA stabilization. Co‐stimulation with dsRNA and IL‐17A resulted in an accumulation of IκBζ. The synergistic upregulation of IL‐36γ and proinflammatory mediators were inhibited by IκBζ siRNA. Co‐stimulation with IL‐17A and poly(I:C) markedly activated the p38 MAPK and NF‐κB pathway, compared with poly(I:C). Blockade of p38 MAPK and NF‐κB suppressed dsRNA/IL‐17A–mediated IκBζ and IL‐36γ induction. These findings demonstrated that IL‐17A synergistically enhanced the dsRNA‐mediated IL‐36γ production through a p38 MAPK‐, NF‐κB–, and IκBζ‐dependent mechanism.  相似文献   
78.
目的研究快速成型(RP)技术辅助下制作的个体化假体复合珊瑚羟基磷灰石(CHA)、重组人骨形成蛋白2(rhBMP-2)修复兔下颌骨缺损的成骨效果。 方法以27只新西兰大白兔为实验对象,随机数字表法平均分成3组(每组9只),全部建立下颌骨连续性缺损模型,并在兔下颌骨缺损区分别植入个体化假体+自体骨(A组)、个体化假体+CHA(B组)、个体化假体+CHA+rhBMP-2(C组)。分别于术后4、12、24周3个时间点处死动物取材,进行大体标本观察,以及骨钙素(OC)、Ⅰ型胶原(COL-1)的免疫组化观察,分别比较各组修复骨缺损的能力,并对实验数据进行重复测量设计资料的单因素方差分析。 结果术后24周各组实验兔外形均对称,通过OC及COL-1的吸光度检测,骨缺损区均有大量新骨形成,A组(0.537 ± 0.010)、C组(0.530 ± 0.010)可见大量骨小梁及编织骨结构,缺损区的新骨OC、COL-1的免疫组化观察基本一致,差异无统计学意义(t = 0.007,P>0.05);但A组强于B组(0.415 ± 0.009,t = 0.122,P<0.001);C组也强于B组(t = 0.121,P<0.001),差异均有统计学意义。 结论在兔下颌骨缺损修复中,通过RP技术和组织工程技术相结合,CHA复合rhBMP-2后成骨能力明显增强,成骨效能肯定,为后期的临床应用提供可靠的实验基础。  相似文献   
79.
Idiopathic rapid eye movement sleep behavior disorder(iRBD) is often a precursor to neurodegenerative disease. However, voxel-based morphological studies evaluating structural abnormalities in the brains of iRBD patients are relatively rare. This study aimed to explore cerebral structural alterations using magnetic resonance imaging and to determine their association with clinical parameters in iRBD patients. Brain structural T1-weighted MRI scans were acquired from 19 polysomnogram-confirmed iRBD patients(male:female 16:3; mean age 66.6 ± 7.0 years) and 20 age-matched healthy controls(male:female 5:15; mean age 63.7 ± 5.9 years). Gray matter volume(GMV) data were analyzed based on Statistical Parametric Mapping 8, using a voxel-based morphometry method and two-sample t-test and multiple regression analysis. Compared with controls, iRBD patients had increased GMV in the middle temporal gyrus and cerebellar posterior lobe, but decreased GMV in the Rolandic operculum, postcentral gyrus, insular lobe, cingulate gyrus, precuneus, rectus gyrus, and superior frontal gyrus. iRBD duration was positively correlated with GMV in the precuneus, cuneus, superior parietal gyrus, postcentral gyrus, posterior cingulate gyrus, hippocampus, lingual gyrus, middle occipital gyrus, middle temporal gyrus, and cerebellum posterior lobe. Furthermore, phasic chin electromyographic activity was positively correlated with GMV in the hippocampus, precuneus, fusiform gyrus, precentral gyrus, superior frontal gyrus, cuneus, inferior parietal lobule, angular gyrus, superior parietal gyrus, paracentral lobule, and cerebellar posterior lobe. There were no significant negative correlations of brain GMV with disease duration or electromyographic activity in iRBD patients. These findings expand the spectrum of known gray matter modifications in iRBD patients and provide evidence of a correlation between brain dysfunction and clinical manifestations in such patients. The protocol was approved by the Ethics Committee of Huashan Hospital(approval No. KY2013-336) on January 6, 2014. This trial was registered in the ISRCTN registry(ISRCTN18238599).  相似文献   
80.
Objective To investigate the predictive factors affecting the efficacy of cyclophosphamide (CTX) combined with glucocorticoids in the treatment of idiopathic membranous nephropathy (IMN), and to evaluate the efficacy of calcineurin inhibitor (CNI) adjustment due to poor treatment. Methods A retrospective cohort study was conducted. Two hundreds and twenty-eight patients with IMN diagnosed by renal biopsy in the People's Hospital of Guangxi Zhuang Autonomous Region from January 1, 2007 to December 1, 2016 were enrolled. All subjects were treated with CTX in combination with glucocorticoids. The patients were divided into two groups: remission group and no remission group. Multivariable logistic regression analysis was used to determine the baseline clinical-pathological influencing factors for the remission of IMN in the enrolled patients. Results The number of total remission (including complete and partial remission) of the first CTX combined with glucocorticoid treatment in 228 patients with IMN was 188(82.5%). Among them, 141 patients (61.8%) had complete remission (CR), the median time for CR was 8(6, 12) months, and the median time for partial remission (PR) was 3(1, 4) months. The median follow-up time for this study was 25(13, 43) months. Compared with the remission group, the serum albumin level was lower in the non-remission group, the 24-hour urine protein content, the blood complement C3 and C4 levels were higher, and the pathological stage was milder (all P﹤0.05). Multivariate logistic regression analysis suggested that the levels of baseline serum albumin, complement C4, and pathological stage were independent predictors of clinical remission in IMN patients. Twenty-four non-remission patients were treated with CNI. The overall response rate was 66.7%(16/24) at 6 months and 77.3%(17/22) at 12 months. Conclusions The levels of baseline albumin, blood complement C4, and pathological stage were independent predictors of clinical remission in IMN patients treated with CTX plus glucocorticoids. The non-remission patients with CTX combined with glucocorticoid therapy can still achieve a higher response rate after adjusting for CNI.  相似文献   
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