19例经导管主动脉瓣植入术患者的护理及治疗效果评价

目的：总结经导管主动脉瓣植入术(TAVI)治疗重度主动脉瓣狭窄的术前术后护理经验,并对治疗效果进行评价。方法：选取2016年3月—2020年4月19例行TAVI术患者为研究对象,术前充分了解病情,完善相关检查,给予饮食、活动及心理护理,术后观察病情变化并对症处理。分别在术前和术后1,3,6个月评估心功能分级(NYHA),并监测主动脉瓣口面积、左心射血分数(LVEF)及血清N端脑钠肽前体(NT-ProBNP)等指标,评价治疗效果。结果：19例患者均康复出院,随访半年治疗效果良好,生活质量改善。术前NYHA分级Ⅲ级10例、Ⅳ级9例,术后6个月NYHA分级Ⅰ级15例、Ⅱ级4例;术后主动脉瓣口面积、LVEF、血清NT-ProBNP与术前比较,差异均有统计学意义(P<0.05)。结论：TAVI操作难度大、并发症多,术前应全面评估,预见性发现问题,根据患者出现的情况行针对性处理,并于术后对患者实施全面持续的护理,可提高治疗效果。     

不同给药途径时抗核抗体独特型多肽对狼疮样肾炎小鼠作用的探讨

目的应用抗核抗体独特型多肽免疫治疗狼疮肾炎小鼠,观察其对狼疮肾炎模型小鼠肾脏的保护作用。方法将35只雌性GVHD狼疮样肾炎小鼠(C57BL/10×DBA/2)F1分为3组,肾炎模型对照组(10只),口服多肽实验组(10只),皮下注射多肽实验组(15只)。3组小鼠均于24周龄处死,观察3组小鼠体质量、尿蛋白、肾脏组织学及血清IL-6水平的变化。结果在给予多肽12周时,皮下注射组和口服多肽组小鼠肾脏损害较对照组明显减轻;血清IL-6水平也较对照组明显降低。在给予多肽10周时,皮下注射组小鼠体质量明显高于对照组小鼠,12周时口服组体质量也明显高于对照组。给予多肽4周时,皮下注射组小鼠尿蛋白明显少于对照组,8周时口服组尿蛋白也明显少于对照组。结论口服独特型多肽对GVHD狼疮样肾炎小鼠肾脏同样有保护作用。     

视网膜脱离手术后黄斑区OCT图形特征

目的:观察孔源性视网膜脱离手术后视网膜复位及视力恢复情况;黄斑区OCT图形特征。方法:77例77眼裂孔型视网膜脱离在巩膜扣带术前后,行除常规检查外,拍摄眼底像,行黄斑区OCT检查[以黄斑中心凹为中心"十"字扫描,5.62mm标准扫描线,测量中心凹神经纤维(NF)厚度,及视网膜下残液量,并打印出图像];术后1wk;1,2,3,6mo随访矫正视力、眼底及OCT。结果:本组视网膜脱离患者手术后临床复位率100%,而OCT扫描显示,术后1wk解剖复位率52%,术后1mo62%,术后2mo71%,术后3mo75%,术后6mo87%;术后视力在3～6mo内逐渐提高并稳定;黄斑区OCT图形异常提示视功能改善差。结论:OCT是视网膜脱离手术前后了解和观察病情、预测预后的可靠手段。     

2019年“农村义务教育学生营养改善计划”覆盖地区学生餐剩饭状况及影响因素分析

目的:分析我国“农村义务教育学生营养改善计划”覆盖地区中小学学生餐剩饭情况及影响因素。方法:2019年在“农村义务教育学生营养改善计划”覆盖地区699个县中,分片选取1~3个国家试点县,共选取50个重点监测县。按照不同供餐模式,随机各抽取2所小学和2所初中作为重点监测学校。从小学三年级到初中三年级,每个年级抽取1~2个...     

Numerical Investigation of the Influence of Ultimate-Strength Heterogeneity on Crack Propagation and Fracture Toughness in Welded Joints

The mechanical properties of dissimilar metal-welded joint materials are heterogeneous, which is an obstacle to the safety evaluation of key welded structures. The variation of stress–strain conditions at the crack tip caused by mismatch of material mechanical properties in dissimilar metal-welded joints is an important factor affecting crack propagation behavior. To understand the influence of uneven distribution of ultimate strength of the base metal and the welded metal on the crack propagation path, fracture toughness, as well as the mechanical field at the crack tip in the small-scale yield range, the user-defined field variable subroutine method is used to express continuous variation characteristics of welded joint ultimate strength in finite element software. In addition, the J-integral during crack propagation is calculated, and the effect of the ultimate strength on the J-integral and the stress field at the crack tip are analyzed. The results show that as the crack propagation direction is perpendicular to the direction of ultimate strength, the gradient of ultimate strength increases from |G_y|= 50 to |G_y|= 100 MPa/mm, the crack deflection angle increases by 0.018%, and the crack length increases by 1.46%. The fracture toughness of the material decreased slightly during crack propagation. Under the condition that the crack propagation direction is the same as the direction of ultimate strength, the crack propagation path is a straight line. As the gradient of ultimate strength increases from G_x = 50 to G_x = 100 MPa/mm, the crack propagation length decreases by 5.17%, and the slope of fracture toughness curve increases by 51.63%. On the contrary, as the crack propagates to the low ultimate strength side, the crack propagation resistance decreases, the ultimate strength gradient increases from G_x = −100 to G_x = −50 MPa/mm, and the slope of the fracture toughness curve decreases by 51.01%. It is suggested to consider the relationship between crack growth behavior and ultimate strength when designing and evaluating the structural integrity of cracks at the material interface of dissimilar metal-welded joints.     

Exosomes Derived from Glioma Cells under Hypoxia Promote Angiogenesis through Up-regulated Exosomal Connexin 43

Glioblastoma multiform (GBM) is a highly aggressive primary brain tumor. Exosomes derived from glioma cells under a hypoxic microenvironment play an important role in tumor biology including metastasis, angiogenesis and chemoresistance. However, the underlying mechanisms remain to be elucidated. In this study, we aimed to explore the role of connexin 43 on exosomal uptake and angiogenesis in glioma under hypoxia. U251 cells were exposed to 3% oxygen to achieve hypoxia, and the expression levels of HIF-1α and Cx43, involved in the colony formation and proliferation of cells were assessed. Exosomes were isolated by differential velocity centrifugation from U251 cells under normoxia and hypoxia (Nor-Exos and Hypo-Exos), respectively. Immunofluorescence staining, along with assays for CCK-8, tube formation and wound healing along with a transwell assay were conducted to profile exosomal uptake, proliferation, tube formation, migration and invasion of HUVECs, respectively. Our results revealed that Hypoxia significantly up-regulated the expression of HIF-1α in U251 cells as well as promoting proliferation and colony number. Hypoxia also increased the level of Cx43 in U251 cells and in the exosomes secreted. The uptake of Dio-stained Hypo-Exos by HUVECs was greater than that of Nor-Exos, and inhibition of Cx43 by ^37,43gap27 or lenti-Cx43-shRNA efficiently prevented the uptake of Hypo-Exos by recipient endothelial cells. In addition, the proliferation and total loops of HUVECs were remarkably increased at 24 h, 48 h, and 10 h after Hypo-Exos, respectively. Notably, ^37,43gap27, a specific Cx-mimetic peptide blocker of Cx37 and Cx43, efficiently alleviated Hypo-Exos-induced proliferation and tube formation by HUVECs. Finally, ^37,43gap27 also significantly attenuated Hypo-Exos-induced migration and invasion of HUVECs. These findings demonstrate that exosomal Cx43 contributes to glioma angiogenesis mediated by Hypo-Exos, and suggests that exosomal Cx43 might serve as a potential therapeutic target for glioblastoma.     

胃癌根治术静脉小剂量氯胺酮复合硬膜外吗啡超前镇痛的效果观察

目的　观察胃癌根治术中静脉小剂量氯胺酮复合硬膜外吗啡超前镇痛与对照组术后镇痛效果及吗啡用量。方法　选择胃癌择期手术患者60例,ASAⅠ~Ⅱ级,随机分为三组,每组各20例,三组均采用硬膜外复合全麻。A组(试验组)静脉小剂量氯胺酮复合硬膜外吗啡超前镇痛,B组仅硬膜外吗啡超前镇痛,C组(对照组)未用超前镇痛。三组术后均采用术后镇痛。分别记录术后6、12、24、48小时的BP、RR、HR、SPO2、VAS(疼痛评分)、吗啡用量。结果 A组在4个时间点VAS均为最低,与B组、C组相比差异有显著性(P<0.05)。6h、12hB组与C组VAS比较差异有显著性(P<0.05),24h、48h差异无显著性(P>0.05)。A组PCEA(病人自控硬膜外镇痛)吗啡累积消耗量在4个时间点均为最低,与B组、C组比较差异有显著性(P<0.05);B组与C组的吗啡累积消耗量在4个点比较差异均有显著性(P<0.05)。结论　为胃癌根治术患者达到满意的超前镇痛,并且尽量减少术后吗啡及其它阿片类药物的使用,可使用静脉小剂量氯胺酮复合硬膜外吗啡超前镇痛的方法,这种方法可以同时发挥外周及中枢的镇痛作用。     

白塞综合征20例临床特征及心血管影像学分析

回顾性分析2018年1月—2020年8月首都医科大学附属北京安贞医院风湿免疫科治疗的白塞综合征患者20例的临床及影像学检查资料.20例患者中,男4例,女16例,平均年龄41.2岁,平均病程17.0年.超声、CT及MR检查发现心血管系统受累13例,主要表现为主动脉瓣脱垂并重度关闭不全,主动脉瘤、主动脉假性动脉瘤、主动脉溃...     

Der p 2基因真核表达载体构建及其在小鼠树突状细胞中的表达

背景：树突状细胞是目前已知的最强大的抗原提呈细胞，已经被应用于免疫治疗的研究中。 目的：构建Der p 2真核表达载体，并证明能在小鼠骨髓来源的树突状细胞中表达。 设计、时间及地点：单一样本观察，实验于2005-05/12在解放军第三军医大学新桥医院全军呼吸疾病研究所完成。 材料：C57BL/6小鼠；plambd-Der p 2购自美国HESKA公司；pCI-neo质粒为解放军第三军医大学新桥医院全军呼吸疾病研究所保存。 方法：体外分离，培养小鼠骨髓来源树突状细胞。将原核表达质粒plambdDer p 2携带的Der p 2全长cDNA切下，重组到真核表达质粒pCI-neo中，然后在脂质体介导下，将重组质粒转染到小鼠骨髓来源的树突状细胞，以未转染质粒和转染空白载体pCI-neo的树突状细胞为对照。 主要观察指标：①pCI-neoDer p 2重组质粒结构鉴定。②并用反转录-聚合酶链反应、Western Blot检测Der p 2mRNA和蛋白表达。 结果：测序证实构建的重组质粒中携带了Der p 2的全长cDNA序列，且与Gene Bank序列完全一致。反转录-聚合酶链反应和Western Blot检测结果提示，重组质粒转染的树突状细胞能表达Der p 2 mRNA和Der p 2蛋白。 结论：成功构建重组Der p 2基因真核表达载体，其转染树突状细胞后，能有效地表达于树突状细胞中。     

β-FIBRINOGEN PROMOTER-455 G／A （HaeⅢ） POLYMORPHISM PREDICTION OF PLASMA FIBRINOGEN BUT NOT OF ISCHEMIC CEREBROVASCULAR DISEASE

Objective The-455 G/A (HaeⅢ) polymorphism of β-fibrinogen gene influences levels of plasma fibrinogen. We further investigated whether it influences the risk of isehemie cerebrovaseular disease. Methods We accumulated 134 acute isehemic eerebrovaseular disease (ICVD) eases and compared their -455 G/A status with a control group (n=166). The β-fibrinogen gene -455 G/A polymorphism was analyzed for all subjects by PCR-RFLP with the restrictive enzyme HaeⅢ. Results Plasma fibrinogen was higher in AA homozygous participants (341mg/dL) than in participants carrying the G allele: GA (290mg/dL), GG (298mg/dL) in the control group. Plasma fibrinogen was also higher in AA homozygous patients (353mg/dL) than in eases carrying the G allele: GA (287mg/dL), GG (302mg/dL) in the ICVD group. However, there was no significant association between β-fibrinogen gene -455 G/A polymorphism and ICVD group. Conclusions Although a small effect cannot be excluded, β-fibrinogen gene -455 G/A polymorphism is an independent predictor of plasma fibrinogen, but not of isehemie cerebrovaacular disease.