姜黄素对大鼠子宫内膜异位症影响的实验研究#br#

目的：分析姜黄素对大鼠子宫内膜异位组织转录因子Twist1、Twist2、E-钙黏蛋白（E-cadherin）、Syndecan-1表达的影响。方法：选取SPF级雌性SD大鼠采用自体内膜移植法建立子宫内膜异位症大鼠模型，将造模成功的30只大鼠随机分为模型组、低剂量姜黄素组（25 mg·kg-1·d-1）、中剂量姜黄素组（50 mg·kg-1·d-1）、高剂量姜黄素组（100 mg·kg-1·d-1）、孕三烯酮组（0.5 mg·kg-1·d-1），每组各6只，设立5只大鼠假手术组为空白对照组，记录各组大鼠异位内膜组织体积；采用免疫组化法检测各组大鼠子宫内膜异位组织Twist1、Twist2、E-cadherin、Syndecan-1表达的变化。结果：与模型组相比，姜黄素各剂量组和孕三烯酮组大鼠异位组织体积明显较低，差异具有统计学意义（P<0.05）；Twist1阳性主要定位于细胞核中，Twist2阳性主要定位于细胞质中，E-cadherin、Syndecan-1阳性染色主要定位于上皮细胞膜上，少见于个别细胞质。与模型组相比，姜黄素各剂量组和孕三烯酮组Twist1、Twist2、Syndecan-1评分均明显降低，E-cadherin评分明显升高（P<0.05），低中剂量姜黄素组Twist1、Twist2、Syndecan-1评分明显高于孕三烯酮组，E-cadherin评分低于孕三烯酮组（P<0.05），高剂量姜黄素组Twist1、Twist2、E-cadherin、Syndecan-1评分与孕三烯酮组比较差异无统计学意义（P>0.05）。 结论：姜黄素可降低子宫内膜异位组织中Twist1、Twist2、Syndecan-1的表达，升高E-cadherin的表达，抑制模型大鼠异位内膜的生长，以达到治疗的目的。     

镧和铈在Y型分子筛方钠石笼中的定位差异以及对FCC催化剂反应性能的影响

用新型制备工艺分别制备镧和铈改性的Y型分子筛，并通过X衍射法、分光光度法和ACE反应评价等手段考察两种稀土元素在Y型分子筛中的定位状况、制备过程中的利用率、水热稳定性以及反应性能的差异。研究发现，镧在较低能耗条件下容易实现在Y型分子筛方钠石笼中的定位。同时，镧改性的Y型分子筛还具有稀土利用率高、热和水热稳定性好等特点。ACE评价结果表明，镧改性Y型分子筛制备的催化剂在反应性能上有明显优势。     

多媒体技术在非化学专业无机及分析化学教学中的应用探讨

文章主要介绍了将多媒体技术应用于非化学专业无机及分析化学教学的实践与体会。指出应正确认识多媒体技术在无机及分析化学教学中的地位和作用,合理利用多种教学手段,提高教学质量。     

Purification Mechanism of Quartz Sand by Combination of Microwave Heating and Ultrasound Assisted Acid Leaching Treatment

Silicon - Iron is a major impurity in quartz sand and must be strictly removed in many applications. However, the iron removal rate in most of the conventional purification process is not high...     

美国IEER标准简析

对美国IEER标准进行详细介绍。美国标准ANSI／AHRI Standard 340／360—2007给出IEER的定义为：它是用于评价工商用单元式空调机和热泵设备部分负荷能效的单一数值的指标,它的计算是基于被测设备在不同负荷工况下加权的EER。该标准还规定IEER评价指标于2010年1月1日起替代IPLV指标作为对于制冷量≥19kW（65Btu／h）的商业和工业用单元式空调机及热泵设备的评价指标。分析美国标准中商用单元式空调机与热泵设备的评价指标从IPLV改变为IEER的原因。从4个方面比较lEER和JPLV的区别。在新标准的测试条件下,IEER指标可促进生产厂家开发高效压缩机,推动系统换热器匹配和部分负荷下的优化等。这些经验可供我国制定相关标准时借鉴。     

我国热泵热水机能效水平分析

对我国热泵热水机的能效现状进行调研,结果显示有约1/3的空气源普通型热泵热水机及超过1/2的水源热泵热水机产品的COPh不能达到GB/T 21362—2008中相应要求。提出采用热力学完善度(η)分析的方法,并参照我国现有房间空调器、单元式空调机及冷水机组的能效等级标准,分析热泵热水机的能效等级标准。建议该标准分为3级,其中水源式1～3级COPh/ηh依次为5.1/0.407、4.8/0.382、4.5/0.359,空气源普通式相应值依次为4.3/0.296、4.0/0.276、3.7/0.255。     

Synthesis and characterization of dextran-capped silver nanoparticles with enhanced antibacterial activity

Dextran-capped silver nanoparticles were synthesized by reducing silver nitrate with NaBH4 in the presence of dextran as capping agent. The characters of silver nanoparticles were investigated using UV-Vis spectrophotometer, nano-grainsize analyzer, X-ray diffraction, and transmission electron microscopy. Results showed that the silver nanoparticles capped with dextran were in uniform shape and narrow size distribution. Moreover, compared with polyvinylpyrrolidone (PVP)-capped silver nanoparticles, the dextran-capped ones possessed better stability. Antibacterial tests of these silver nanoparticles were carried out for Escherichia coli, Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, and Klebsiella pneumoniae. Results suggested that the dextran-capped silver nanoparticles had high antibacterial activity against both Gram-positive and Gram-negative bacteria. In addition, the cytotoxicity in vitro of the dextran-capped silver nanoparticles was investigated using mouse fibrosarcoma cells (L929). The toxicity was evaluated by the changes of cell morphology and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide assay. Results indicated that these silver nanoparticles had slight effect on the survival and proliferation of L-929 cells at their minimal inhibitory concentration (MIC). After modified by dextran, the physiochemical properties of the silver nanoparticles had been improved. We anticipated that these dextran-capped silver nanoparticles could be integrated into systems for biological and pharmaceutical applications.     

Autologous urothelial cells transplantation onto a prefabricated capsular stent for tissue engineered ureteral reconstruction

In this study, we have fabricated an artificial ureter by transplantation of in vitro-expanded urothelial cells onto an in vivo-prefabricated capsular stent using tissue engineering methods. Spiral poly (l-lactic acid) (PLLA) stents were transplanted into the subcutaneous of Wistar rats for a period of 1, 2 or 3 weeks to induce the formation of connective tissue capsules on their surfaces. The capsular PLLA stents were then decellularized and further recellularized with bladder epithelial cells to fabricate artificial ureters. The results showed that the entrapped cells in all capsules remained continuously proliferation and lined up in continuous layers. In addition, the urothelial cells on the capsular stents with an embedding period of 2 or 3 weeks showed higher proliferative viability compared with the cells on the stents with an embedding time of 1 week (P < 0.05). The results of the study indicated that the prefabricated capsular stents could serve as alternative cell carriers for tissue engineered ureters, especially with embedding time from 2 to 3 weeks.     

电浮选方法在废水处理中的应用

利用电浮选方法处理废水,具有设备简单、高效、清洁、不会引起二次污染等优点。该文综述了电浮选方法处理废水的基本原理、应用现状及影响浮选效率的主要因素pH、电流密度、浮选时间,重点介绍了气浮槽、电极材料等电浮选装置,并指出了利用该方法处理废水的发展方向。     

我的矿工兄弟

矿区的夜晚，没有城市的喧嚣、繁华、霓虹灯的点缀，也没有那乡村夜晚的宁静，但也并不缺乏热闹的气息和那份矿区夜晚所独有的“宁静”。