Clodronate-containing liposomes attenuate lung injury in rats with severe acute pancreatitis

Objectives:Severe acute pancreatitis(SAP) can lead to acute lung injury(ALI) .The purpose of this paper is to investigate the protective effect of clodronate-containing liposomes on ALI in rats with SAP.Methods:The thin film method was used to prepare liposomes.Sprague-Dawley rats were randomly divided into three groups.After the SAP model was established by injecting 5%(w/v) sodium taurocholate(2 ml/kg body weight) into the subcapsular space of the pancreata,normal saline was administered to the control(C) group,phosphate buffer solution(PBS) -containing liposome to the Pgroup,and clodronate-containing liposome to the Tgroup through tail veins.Blood samples were obtained from the superior mesenteric vein at 2 and 6 h to measure the levels of amylase,interleukin-6(IL-6) ,and tumor necrosis factor-α(TNF-α) .Morphological changes in the pancreata and lung were observed using hematoxylin and eosin(HE) staining,while cell apoptosis was detected using terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling(TUNEL) .In addition,the macrophage marker cluster of differentiation 68(CD68) in lung tissue was detected with immunohistochemistry.Results:Blood levels of amylase,IL-6,and TNF-αwere significantly increased in the Pgroup compared to those in the Tgroup(P0.05) .In the Tgroup,large numbers of TUNEL-positive cells were observed,but no or few in the C and Pgroups.Gross inspection and HE staining of pancreata and lung showed dramatic tissue damage,including inflammation and necrosis in the Pgroup.Less remarkable changes were noted in the Tgroup,and the C group exhibited normal histology.The histological scores according to Kaiser's criteria were consistent with HE findings.The number of CD68-positive macrophages decreased in the Tgroup.Conclusions:Clodronate-containing liposomes have a protective effect against ALI in rats with SAP.Blockade of macrophages may represent a novel therapeutic strategy in SAP.     

Development of a large-scale isolation chamber system for the safe and humane care of medium-sized laboratory animals harboring infectious diseases

The close phylogenetic relationship between humans and non-human primates makes non-human primates an irreplaceable model for the study of human infectious diseases. In this study, we describe the development of a large-scale automatic multi-functional isolation chamber for use with medium-sized laboratory animals carrying infectious diseases. The isolation chamber, including the transfer chain, disinfection chain, negative air pressure isolation system, animal welfare system, and the automated system, is designed to meet all biological safety standards. To create an internal chamber environment that is completely isolated from the exterior, variable frequency drive blowers are used in the air-intake and air-exhaust system, precisely controlling the filtered air flow and providing an air-barrier protection. A double door transfer port is used to transfer material between the interior of the isolation chamber and the outside. A peracetic acid sterilizer and its associated pipeline allow for complete disinfection of the isolation chamber. All of the isolation chamber parameters can be automatically controlled by a programmable computerized menu, allowing for work with different animals in different-sized cages depending on the research project. The large-scale multi-functional isolation chamber provides a useful and safe system for working with infectious medium-sized laboratory animals in high-level bio-safety laboratories.     

转变职能,创新教研的制度和机制

教研员一直在各级各类教育教学研究工作中发挥着主要作用。在新课程改革向纵深发展的今天,教研如何适应新课程与教学改革的需要,如何创新教研制度和机制,在新课程改革实验中更好地发挥研究、指导和服务的功能,本文将从教研机构职能的转变,教研方式改变,教研制度机制创新等方面加以探讨。     

Improved response surface method for anti-slide reliability analysis of gravity dam based on weighted regression

The aim of this study was to design and construct an improved response surface method （RSM） based on weighted regression for the anti-slide reliability analysis of concrete gravity dam. The limitation and lacuna of the traditional RSM were briefly analyzed. Firstly, based on small experimental points, research was devoted to an improved RSM with singular value decomposition techniques. Then, the method was used on the basis of weighted regression and deviation coefficient correction to reduce iteration times and experimental points and improve the calculation method of checking point. Finally, a test example was given to verify this method. Compared with other conventional algorithms, this method has some strong advantages： this algorithm not only saves the arithmetic operations but also greatly enhances the calculation efficiency and the storage efficiency.     

HNCO hydrolysis performance in urea-water solution thermohydrolysis process with and without catalysts

The thermolysis of urea-water solution and its product, HNCO hydrolysis is investigated in a dual-reactor system. For the thermal decomposition below about 1073 K, the main products are ammonia (NH3) and isocyanic acid (HNCO) whereas at higher temperatures the oxidation processes take effect and the products include a low concentration of nitric oxide (NO) and nitrous oxide (N2O). The gas HNCO is quite stable and a high yield of HNCO is observed. The ratio of NH3 to HNCO increases from approximately 1.2 to 1.7 with the temperature. The chemical analysis shows that H radical is in favor of HNCO hydrolysis by instigating the reaction HNCO+H·→·NH2+CO and high temperature has positive effect on H radical. The hydrolysis of HNCO over an alumina catalyst made using a sol-gel process (designated as γ-Al2O3) is investigated. The conversion of HNCO is high even at the high space velocities (6×105 h-1) and low temperatures (393–673 K) in the tests with catalysts, which enhances HNCO hydrolysis and raises the ratio of NH3 to HNCO to approximately 100. The pure γ-Al2O3 shows a better catalytic performance than CuO/γ-Al2O3. The addition of CuO not only reduces the surface area but also decreases the Lewis acid sites which are recognized to have a positive effect on the catalytic activity. The apparent activation energy of the hydrolysis reaction amounts to about 25 kJ/mol in 393–473 K while 13 kJ/mol over 473 K. The overall hydrolysis reaction rate on catalysts is mainly determined by external and internal mass-transfer limitations.     

浅谈元素及其化合物性质实验教学

针对元素及其化合物性质实验的特点,从优选实验内容、研究实验过程、探索教学方法三个方面探讨了元素及其化合物性质实验的教学。     

Recurrent severe vomiting due to hyperthyroidism

Thyrotoxicosis may present in many ways; severe vomiting as a prominent symptom of thyrotoxicosis is uncommon. In this paper, we report a 24-yearoold Chinese male with hyperthyroidism who presented with recurrent severe vomiting. The patient had had intermittent vomiting for seven years and had lost approximately 15 kg of weight. Gastroscopic examinations revealed chronic gastritis and one occasion peptic ulcer. He was treated with antacid and proton pump inhibitors, but his symptoms had no relief. His presenting symptoms suggested hyperthyroidism and were confirmed by laboratory data. After a month of propylthiouracil therapy, his symptoms were relieved. It should be noted that hyperthyroidism patients can have unexplained vomiting, and that hyperthyroidism may coexist with peptic ulcer in rare cases. Awareness of such atypical presentations of hyperthyroidism may help to make a correct diagnosis.     

Effect of increased intra-abdominal pressure and decompressive laparotomy on aerated lung volume distribution

Increased intra-abdominal pressure(IAP) is common in intensive care patients,affecting aerated lung volume distribution.The current study deals with the effect of increased IAP and decompressive laparotomy on aerated lung volume distribution.The serial whole-lung computed tomography scans of 16 patients with increased IAP were retrospectively analyzed between July 2006 and July 2008 and compared to controls.The IAP increased from(12.1±2.3) mmHg on admission to(25.2±3.6) mmHg(P<0.01) before decompressive lap...     

一种基于虚拟社区的大学生创新能力培养平台

提高大学生的创新意识和创新精神,培养出具有创新能力的高素质人才是现代高等教育的主要目标之一。通常的培养方式在课堂内实施,但课外培养的平台比较缺乏。提出了基于虚拟社区培养创新能力的方法,并应用JXTA技术及Web服务建立了虚拟社区平台,为学生的创新能力培养提供了新的场所。实践测试表明,虚拟社区形式的创新能力培养方法,能够有效地弥补课堂中难以达到的培养目标,为创新能力的培养提供了一条新的途径。     

论房地产价格的理性回归

从目前来看,在国家近期一系列针对房地产市场调控政策密集出炉的情况下,房地产市场必将迎来极为关键的一年,预计全年仍将保持平稳运行态势,但投资、销售增速将有所放缓。住房直接关系到人民群众的日常生活,遏制房价过快上涨有利于房地产市场平稳健康发展,有利于满足老百姓不断增长的物质需求,有利于推动经济平稳较快发展,有利于促进社会和谐与稳定。所以,遏制房价过快上涨,引导房地产价格理性回归,于国于民有利。