负载氯喹的骨靶向纳米颗粒打破肿瘤细胞增殖与骨吸收之间的恶性循环

肿瘤细胞增殖与骨吸收之间的恶性循环加剧了骨肿瘤的进展和转移风险.为此,我们设计并制备了聚乙二醇-阿仑膦酸钠修饰的聚多巴胺(PPA)纳米粒子,并在其表面负载自噬抑制剂氯喹(CQ),期望利用该治疗载体(PPA/CQ)打破肿瘤细胞增殖与骨吸收之间的恶性循环,从而有效地治疗骨肿瘤.实验证明,PPA/CQ可以有效地富集到骨组织,...     

新型高效冷渣机的研制和经济分析

循环流化床锅炉是当代燃煤锅炉中脱硫效益最高的设备,本文对国内现有循环流化床锅炉的冷渣方式进行了综合述评,并着重推荐一种简单、高效、耐用,节能的干式冷渣机.该新型冷渣机应用了一种全新旋转抛洒推进技术,运行可靠性大大提高,固体燃料在推进过程中水冷与风冷相结合,可以在较短的筒体中完成必须的冷却,产生非常显著的节能、环保和社会效益.     

Hydrodynamic characteristics and noise reduction mechanism of a wave leading hydrofoil placed in the wake of a cylinder

We have investigated the hydrodynamic and acoustic performance of a hydrofoil with a wave leading edge that is being ingested in a cylindrical wake,to explore the interaction and noise reduction mechanism with the use of near flow field and far field noise decoupled prediction methods of large eddy simulation(LES)and Ffowcs Williams-Hawkings(FW-H).Our results indicate that the wave leading edge has minimal effect on the hydrodynamic performance,however,it has demonstrated the ability to significantly improve the acoustic performance.Through the comparison of sound pressure level(SPL)and acoustic directivity,we have observed that the wave leading edge can significantly reduce the broadband noise in the far field.This is due to its ability to break the large-scale structure of the incoming flow,which weakens the direct impact and therefore reduces the tone noise.Additionally,the interaction between the broken vortex and the boundary layer around the hydrofoil surface is weakened,leading to a reduction in surface pressure pulsation and broadband noise intensity.The wave structure primarily affects the flow structure near the leading edge,resulting in a reduction in flow disturbance and sound source intensity,and an improvement in the acoustic feedback loop between the foil and the fore-cylinder.     

氨茶喊对人体心电图和定量脑电图的影响及其与唾液氨茶碱含量的关系

目的 评价氣茶城对人体心电-图和定量脸电图的影响及其与嗟液氣茶城含量的关系。方法 米 用双盲安慰剂对照, 研究了良茶碱对10例徤康人心电图和定量脑电图的影响。结果 顿服氦茶碱 0. 4g, 2h 后心电图R波振幅从9. 9±2. 8m增高到12. 0±3. 6m(P<0. 05);定量脑电图f_pt导 联a₂波功率值从1. 05±0. 83上升到2. 08±2. 22(P<0. 05), f₃和f₄导联β₁波功率值从 1. 75± 1. 35升高到3. 11±3. 51(P< 0. 05);唾液氩茶碱含量为7. 6±0. 9 μg/ml。心电图R波及 脑电图a₂ 波的变化与哇液氩茶城含量呈正相关（r值分别为0. 8264和0. 7933)。10例口服安慰 剂健康受试者, 其心电困和脑电图改变均无统计学显著性。结论 治疗浓度氩茶碱能引起人体 心电和脑电的改变, 效应强度与游离药物浓度有关。     

LvBMP-2 gene-modified BMSCs combined with calcium phosphate cement scaffolds for the repair of calvarial defects in rats

The study aims to evaluate the effect of bone marrow stromal cells (BMSCs) expressing bone morphogenic protein-2 (BMP-2) mediated by lentiviral (Lv) gene transduction combined with calcium phosphate cement (CPC) scaffolds for the repair of critical size calvarial defects in rats. BMSCs derived from Fisher 344 rats were transduced with LvBMP-2 or lentivirus encoding enhanced green fluorescent protein (LvEGFP) in vitro. Obvious osteogenic differentiation of BMSCs in the LvBMP-2 group was demonstrated by alkaline phosphatase staining and alizarin red staining. Enzyme-linked immunosorbent assay results show that LvBMP-2 gene expression in vitro can last for at least 8 weeks. Gene-transduced or untransduced BMSCs were seeded onto CPC scaffolds to repair rat calvarial defects with a diameter of 5 mm. Scanning electron microscope analysis indicated that porous CPC scaffolds facilitated initial adhesion and spreading of BMSCs onto its surface. Calvarial defects were successfully repaired with LvBMP-2-transduced BMSCs/CPC constructs 8 weeks postoperatively. The percentage of new bone formation in the LvBMP-2 group was significantly higher than in other control groups. Lentiviral mediated BMP-2 gene therapy together with CPC scaffolds can be used successfully in calvarial repair and bone regeneration.     

测深仪失捕情况分析及解决途径

结合两例典型测深仪信号失捕情况,从船舶总体设计、测深仪型号选择和测深仪换能器安装等多方面分析了信号失捕产生的原因,提出了降低测深仪失捕率的几种基本途径。     

软黏土小应变本构模型参数研究与应用

小应变范围内土体刚度的非线性特性是土体的重要特性之一,合理获取小应变参数对基坑工程周边环境变形分析至关重要。以上海软黏土为例,采集了该地区的典型黏土层((2)～(6)层)的原状土样进行了试验研究,提出了由常规岩土勘察报告提供的压缩模量E_s1-2确定刚度参数E_oed^ref、E₅₀^ref、E_ur^ref及小应变剪切模量G^ref₀的方法,给出了R_f、m、ν_ur、γ_0.7等参数的取值范围,结合勘察报告提供的c′、φ′等强度参数指标,可以合理得到HS-Small模型的全套参数,上述方法及模型参数已被纳入上海市《基坑工程技术标准》。最后,基于该方法确定的小应变模型参数,对上海深隧排水系统云岭西超深竖井基坑进行了三维数值分析,验证了小应变本构模型在超深基坑工程中的适用性。     

逆向气流条件下半椭圆管外水平降膜厚度分布研究

为研究半椭圆管水平降膜厚度的分布规律,搭建逆向气流条件下水平降膜实验平台,并结合数字图像处理技术,研究逆流风速(0～5 m/s)和喷淋流量(0.025～0.221 L/min)对液膜厚度的影响。研究表明:逆向气流会对管外水膜产生影响,并存在临界速度;当逆流风速低于临界速度,液膜厚度沿圆周方向先减小后增大,与无空气流动时相似;当逆流风速超过临界速度时,液膜分布严重不均甚至被吹飞;随着逆流风速增大,平均液膜厚度先增大后减小;随着喷淋流量增大,平均液膜厚度持续增大;当喷淋流量减小、逆流风速增大时,平均液膜厚度减小。