Research on Dynamic Strength and Inertia Effect of Concrete Materials Based on Large-Diameter Split Hopkinson Pressure Bar Test

The Split Hopkinson Pressure Bar (SHPB) test device is an important tool to study the dynamic characteristics of concrete materials. Inertial effect is one of the main factors that cause inaccurate results in SHPB tests of concrete materials. To solve this problem, Large-diameter SHPB tests on concrete and mortar were performed. A dynamic increase factor (DIF) model considering strain rate effect and inertia effect was established. This model provides a scientific reference for studying the dynamic mechanical properties of concrete materials. The experimental results indicate that the strain rate effect of concrete is more sensitive than that of mortar, but the inertia effect of mortar is more sensitive than that of concrete. Under the same strain rate, the energy utilization rate, average fragment size, and impact potentiality of mortar are higher than concrete.     

三七治疗动脉粥样硬化的研究进展

动脉粥样硬化(atheroscIerosis,AS)是导致心脑血管事件发生的关键因素,为多种心脑血管疾病共同的病理生理基础.其证候、病机等属于中医理论的"血瘀证".而三七自古便是历代医家常用的活血化瘀之要药.综述近年来三七在治疗动脉粥样硬化方面的研究进展.     

不同家庭照护模式对慢性病患儿生活质量的影响

目的 探讨不同家庭照护模式对慢性病患儿生活质量的影响.方法 采用方便抽样法选取2016年6月至2017年7月在上海市2所三级甲等儿童医院住院的8 ～18岁慢性病患儿394例及其主要照护者作为研究对象,应用一般资料问卷、中文版家庭管理测量量表、儿童生活质量普适性核心量表进行调查.通过SPSS20.O采用聚类分析方法将患儿家庭进行分类,比较不同类型家庭的一般特征及患儿生活质量状况.结果 慢性病患儿家庭照护模式可分为4类:管理有效型、基本适应型、能力欠缺型和管理困难型.4类家庭照护模式中患儿的病程、半年内住院次数、住院天数、缺课天数、是否独生子女、家庭月收入、父母文化程度、父母职业、患儿生活质量总分及各维度得分差异有统计学意义(P＜0.05).多元分层回归结果显示:病程、半年内缺课天数、能力欠缺型和管理困难型家庭照护模式与患儿总体生活质量相关(分别β=-0.119,-0.147,-0.248,-0.294,均P＜0.05),解释了患儿生活质量23.1％的变异量.结论 慢性病患儿家庭采用的4类家庭照护模式与患儿生活质量密切相关,医护人员可根据不同照护模式的特征和差异为慢性病患儿家庭制定更精准的疾病管理计划,有效促进患儿生活质量的改善.     

NRK-52E缺血再灌注损伤时Kim-1、NO变化及虫草对其的干预作用

目的通过抗霉素A(Antimycin A,AA)刺激大鼠肾小管上皮细胞(NRK-52E)模拟体外缺血再灌注损伤过程,观察缺血再灌注损伤时NRK-52E中肾损伤分子-1(kidney injury molecule-1,Kim-1)及NO表达的变化及冬虫夏草对其的干预作用。方法将体外培养的NRK-52E分为对照组、模型组和虫草组。虫草组予含40 mg/L虫草原液的培基预处理。培养72 h后NRK-52E去除培基,予10-10 mol/L抗霉素A(AA)刺激1 h,模拟体外缺血过程,1 h后再加入培基,模拟体外再灌注损伤过程。分别在AA刺激前,AA刺激后1 h,加入培基再灌注10 min,30 min,60 min,120 min共6个时间点终止实验。用流式细胞仪以Annexin V/PI双染法检测细胞凋亡;分别用硝酸还原酶法和ELISA检测细胞上清液Kim-1与NO浓度;用RT-PCR法观察Kim-1 mRNA表达。结果 NRK-52E细胞经AA刺激后,细胞凋亡率显著增高,同时Kim-1表达上调;缺血60 min较缺血前Kim-1蛋白水平增加了3.1倍,再灌注10 min增加了3.6倍(P<0.05)。Kim-...     

肝脏移植术后移植物抗宿主病的诊断和治疗

【目的】 探讨肝脏移植术后移植物抗宿主病（GVHD）的诊断和治疗。【方法】 分析我院2003年10月至2009年6月完成的772例肝脏移植的临床资料,总结肝脏移植术后GVHD的诊断和治疗经验。【结果】 772例肝脏移植术后5例病人发生GVHD,发病率为0.65%（5/772）,5例患者均在肝脏移植后2～5周出现发热、皮疹、腹泻和全血细胞减少,肝功能均接近正常,经皮肤活检和骨髓穿刺检查证实,并排除巨细胞病毒（CMV）和EB病毒感染。经过调整免疫抑制剂,加用IL-2受体单克隆抗体,积极抗感染和支持对症治疗,2例患者痊愈,3例患者死于严重感染、消化道出血和多器官功能衰竭。【结论】 肝脏移植术后GVHD死亡率高,早期诊断,及时调整免疫抑制剂方案,积极抗感染和营养支持是治疗的关键。     

Pregnancy outcomes in women with type 1 diabetes in China during 2004 to 2014: A retrospective study (the CARNATION Study)

BackgroundWe aimed to report pregnancy outcomes of women with type 1 diabetes (T1D) in China, on which data were sparse.MethodsThis is a nationwide retrospective study conducted in 11 general medical centers in 8 cities across China. We investigated the clinical data of all women who attended these centers with a singleton pregnancy and whose pregnancy ended between 1 January 2004 and 31 December 2014. Pregnancies of women with pregestational T1D were ascertained and compared with those of women without T1D.ResultsFrom over 300 000 pregnancies over the 11‐year study period, we identified 265 singleton pregnancies of women with T1D. One maternal death was documented among 265 (0.37%) women with T1D and 83 among 318 486 (0.03%) women without T1D. Women with T1D suffered from higher rates of pregnancy loss (13.21% vs 2.92%, crude risk ratio [cRR] 5.08 [95% CI, 3.56‐7.26]) and preeclampsia (17.74% vs 4.20%, cRR 4.94 [95% CI, 3.60‐6.77]) compared with those without T1D. Infants of these women with T1D had elevated rates of neonatal death (5.65% vs 0.16%, cRR 37.36 [95% CI, 21.21‐65.82]) and congenital malformation(s) (8.26% vs 3.53%, cRR 2.46 [95% CI, 1.54‐3.93]) compared with those of women without T1D. No significant improvement in pregnancy outcomes in women with T1D was observed over the period 2004 to 2014.ConclusionsPregnancy outcomes were persistently poor in women with T1D during 2004 to 2014 in China. Pregnancy care needs to be improved to reduce adverse pregnancy outcomes among Chinese women with T1D.     

TGF-β Induces Foxp3 + T-Regulatory Cells from CD4 + CD25 − Precursors

CD4 + CD25 + regulatory T cells (Tregs) are potent suppressors, playing important roles in autoimmunity and transplantation tolerance. Understanding the signals necessary for the generation and expansion of Tregs is important for clinical cellular therapy, but only limited progress has been made. Recent reports suggest a role for TGF-beta in the generation of Tregs from CD4 + CD25 - precursors, but the mechanism remains unknown. Here, we demonstrate that TGF-beta2 triggers Foxp3 expression in CD4 + CD25 - precursors, and these Foxp3 + cells act like conventional Tregs. The generation of Foxp3 + Tregs requires stimulation of the T-cell receptor, the IL-2R and the TGF-beta receptor. More importantly, strong costimulation through CD28 prevents Foxp3 expression and suppressive function in an IL-4-dependent manner. Furthermore, TGF-beta-driven Tregs inhibit innate inflammatory responses to syngeneic transplanted pancreatic islets and enhance islet transplant survival. Thus, TGF-beta is a key regulator of the signaling pathways that initiate and maintain Foxp3 expression and suppressive function in CD4 + CD25 - precursors. TGF-beta and signaling through TGF-beta receptor, CD28 costimulation and IL-4 may be key components for the manipulation of Treg. The de novo generation of Foxp3 + cells from CD4 + cells has the potential to be used for treatment of autoimmune diseases and induction of transplant tolerance.     

医学生沟通与交流技能培养模式探索

从医学生沟通与交流技能的培养模式入手,探索适合我国国情的培养模式,以达到全球医学教育标准。     

超声造影鉴别诊断涎腺腺样囊性癌与多形性腺瘤的应用价值

背景 涎腺腺样囊性癌(adenoid?cystic?carcinoma,ACC)是涎腺较常见的恶性肿瘤,复发率和转移率高,因形状和特点与良性多形性腺瘤(plemorphic?adenoma,PA)相似,常被误诊为多形性腺瘤.目的 探讨超声造影(contrast-enhanced ultrasound,CEUS)在涎腺A...