查询推荐研究综述

查询推荐是一种提高用户搜索效率的重要技术，其核心任务是帮助用户构造有效查询并以此准确描述用户信息需求。作为当今搜索引擎的核心技术之一，查询推荐吸引了学术界和工业界的广泛关注，一直以来都是信息检索领域中重要的研究主题。本文以国内外会议、期刊发表的有关查询推荐研究的文献为对象，利用归纳总结方法，首先详细梳理了查询推荐中主流方法&mdash;&mdash;基于简单共现信息的方法、基于图模型的方法以及融合多种信息的方法，然后总结评述了评测方法与指标，最后分析了未来可能的研究方向。</p

USB2.0设备接口IP核的OPB接口技术研究和实现

USB接口已经成为嵌入式系统与PC连接的首要选择。为了将USB2.0设备接口IP核和PowerPC微控制器集成,需要解决USBIP核和OPB总线分处不同时钟域,以及IP核内部内存映射的问题。为此我们根据OPB总线协议,研究和比较了OPB总线与IP核连接的两种方式,并利用集成了PPC405核的FPGA对这两种桥接方式进行验证,证明该接口设计是可行的

糖皮质激素受体在翼状胬肉中的表达及意义

【目的】检测糖皮质激素受体-α、β（GR-α、GR-β）在翼状胬肉组织中的表达,探讨其在翼状胬肉发病机制中的作用。【方法】取39例翼状胬肉组织（其中初发30例,复发9例）,应用荧光定量逆转录PCR定量检测GR-α、β mRNA的表达,应用Western blotting技术分析相应的蛋白表达,同时通过免疫组化技术分析蛋白的细胞定位。另外,取9例正常人的球结膜作为对照。【结果】翼状胬肉及正常人的球结膜组织中均表达GR-α mRNA,不表达GR-β mRNA。其中翼状胬肉（39例）中的GR-α mRNA（×10^3拷贝/μg）为10±4,明显高于正常人球结膜中的2.2±0.3（P〈0.01）,经统计检验有显著性差异。但30例初发翼状胬肉与9例复发翼状胬肉组织中的GR-α mRNA表达分别为10±4和10±5,两者无统计学差异（P〉0.05）。Western blotting分析显示GR-α蛋白在翼状胬肉表达显著高于正常人的球结膜组织（P〈0.01）。免疫组化显示GR-α蛋白定位于上皮细胞核,胬肉组阳性表达率为87.2%,显著高于正常球结膜组（阳性表达率为22.2%,P〈0.05）。而GR-β蛋白在两种组织中均不表达。【结论】翼状胬肉组织中GR-α mRNA及其蛋白表达明显增高,但其在翼状胬肉发生、发展中的作用机制尚待于进一步研究

Effects of Heavy Metal and Pollutants on the Non-special Immunity of the Shrimp and Crab

综述了近10a国内外有关重金属、氨态氮、亚硝酸盐、有机污染物等几种环境因子对虾蟹类非特异性免疫影响的研究成果,以期为通过改善养殖环境条件提高虾蟹类自身免疫抗病力提供理论依据。同时,为进一步深入开展该领域的研究工作积累资料。This paper attempted to review and evaluate existing information about the effects of heavy metal,ammonia-N,nitrite and the organic pollutants on the non-special immune response of the shrimp and crab,which providing theory for improving the self-immunity of shrimp and crab by meliorating cultural environment. In addition,it could provide information for further study on this field

Overexpression of VTE1 from Arabidopsis Resulting in High Vitamin E Accumulationand Salt Stress Tolerance Increase in Tobacco Plant~ *

维生素E在动物细胞内具有抗氧化等重要作用,但在植物体内的功能却鲜为人知.本实验利用CaMV35S启动子与来源于拟南芥的编码生育酚环化酶(TC)的cDNA(VTE1)构建的嵌合表达载体,以根癌农杆菌介导的叶盘法转化烟草W38.实验结果表明,具有卡那霉素抗性的再生植株经RT-PCR检测,得到了与阳性对照一致的495bp的目标片段;转基因植株的VE含量比对照植株高2倍左右,个别株系高达11倍.实验还发现,在耐盐性实验中转基因植株对盐的抗性明显高于野生型烟草;同时,在不同盐浓度(150、250mmol/L)胁迫下转基因植株VE含量比未转化植株增加了1.3~1.8倍,首次证明VTE1与植物耐盐性之间的关系.图7参30Vitamin E is an essential antioxidant in the human cells, while its function in plants is unknown. In this study, tobacco W38 was transformed with a construct containing a cDNA insert encoding tocopherol cyclase (VTE1) from Arabidopsis under the control of the cauliflower mosaic virus (CaMV) 35S promoter. The transgenic tobacco plants were confirmed by RT-PCR, which yielded the same PCR product of 495 bp as the positive control. Compared to the wild type controls, up to 11 times of vitamin E were accumulated in different transgenic lines. Interestingly, the over-expression of VTE1 dramatically increased the salt stress tolerance in tobacco plants. To our knowledge, it is first reported that VTE1 can increase salt stress tolerance in plants. Fig 7, Ref 30国家自然科学基金重点项目~

巨噬细胞炎症蛋白-1α在多发性骨髓瘤中的表达

【目的】探讨巨噬细胞炎症蛋白-1α（MIP-1α）在多发性骨髓瘤中的表达及临床意义。【方法】夹心酶联免疫吸附法（ELISA）定量检测实验组43例患者、15例对照组,以及随访37例治疗3疗程后骨髓血浆MIP-1α的水平。【结果】①65.1%患者MIP-1α水平增高,其中实验组明显高于对照组（t=3.569,P=0〈0.01）,实验组中的活动进展期患者明显高于稳定期、正常人及其他血液病患者（P均〈0.05）;骨质破坏〉2处患者明显高于骨质破坏≤2处的患者（t=5.56,P=0〈0.01）。②有效组经治疗3个疗程后MIP-1α水平明显下降（t=3.237,P=0〈0.05）。③MIP-1α与红细胞计数、白蛋白、β2-微球蛋白、骨损分、Durie-Salmon分期相关（P均〈0.05）。【结论】大部分多发性骨髓瘤患者骨髓MIP-1α水平增高,MIP-1α可作为反映骨质破坏及瘤负荷的一项指标,动态监测MIP-1α可预测近期疗效

Application of oil spill identification by GCMS——A case study

通过对中国近海海域一个具体海面溢油事例的研究,提出了通过气相色谱及气质联用技术进行海面溢油鉴别的方法。采用GC-FID对油样中的正构烷烃的主要组分进行定性分析,利用GC-MS对油中难降解的生物标记化合物:霍烷及其他五环三萜类化合物、规则甾烷及重排甾烷类化合物、三芳甾类化合物、多环芳烃进行分析,计算相应的比值并采用"t-分布"方法进行溢油样品和可疑溢油源样的相关分析。结果如下:(1)从GC-FID色谱图可以看出,YY2679与KY0631、KY0632的色谱图极其相似,与其余四个可疑油源的色谱图差异较大。六个可疑油源的R值在0.04~1.95之间,只有KY0631和KY0632的R值小于0.1,KY0633~KY0636与YY2679的差异不是由风化引起的,可以排除,由此可以推断出YY2679溢油样品可能来源于KY0631或KY0632两个可疑溢油源。(2)采用21个生物标志物指标进行相关性判别,KY0631可疑溢油源在比值点的区间范围为95%和98%时,有多个点x或y误差棒均未跨过直线y=x。KY0632可疑溢油源在比值点的区间范围为95%时,各点的x或y误差棒均跨过直线y=x,由此推断YY2679溢油样品和可疑油源KY0632是同一油源。On the basis of a case study,a method to identify the spilled oil at sea was introduced.N-alkane distribution patterns of unknown oil were recognized by gas chromatography-mass spectrometry determined the distribution of a suit of petroleum biomarkers hopanes,triterpanes,regular steranes diasteranes,triaromatic steroids and polycyclic aromatic hydrocarbons.The calculated diagnostic ratios for selected biomarker in the source of the spilled oil were done.The correlation studies compared the spill sample and suspected source were made.The results showed three samples nearly identical GC chromatographic profiles,n-alkane distribution patterns,as well as nearly identical diagnostic ratios.This implies that they were most likely from the same source.In 95%confidence limit,all diagnostic ratios of sample KY0632 is exactly the same as for YY2679,so conclusion that the sample of KY2679 and YY0632 are come from the same source

三七花醇提物 PNFM 对健康人血小板功能的体外作用

【目的】探讨三七花醇提物（PNFM）对由二磷酸腺苷（ADP）诱导的健康志愿者血小板活化、释放、黏附、聚集等功能的影响及机制。【方法】用不同浓度（0、100、300和500μg/mL）的PNFM与健康人的血小板PRP孵育后，在血小板激活剂ADP诱导后，用CD62P及ATP释放以检测血小板颗粒物释放，比浊法检测聚集率，免疫荧光检测血小板在纤维蛋白原上的铺展，用Fluo3-AM钙离子载体标记检测胞浆游离钙的变化。【结果】在激动剂ADP诱导下，500μg/mL的PNFM干预组血小板聚集率从对照组的（72.00±6.08）降到了35.67±3.78（P<0.01），300μg/mL干预组同样有抑制效果；与对照组相比（30.05±6.48），PNFM干预组明显降低健康人血小板表面CD62P，其中500μg/mL组降至（2.66±0.90，P<0.001）；且均降低了PAC-1的表达，500μg/mL组（11.89±6.12）较对照组（33.37±8.12）差异显著（P<0.01）；PNFM干预组均可抑制ATP释放，500μg/mL组由对照的1.93±0.47降至0.19±0.10（P<0.001）；在血小板于纤维蛋白原上的铺展作用中，PNFM各剂量组也均显示有显著抑制作用，500μg/mL组由对照的89.57±17.34降至25.12±3.52（P<0.001）；PNFM同样抑制血小板胞浆钙离子动员，其中500μg/mL组（71.25±5.33）较对照组差异显著（183.87±11.59，P<0.001）；且均具有剂量依赖性。【结论】PNFM可在体外有效抑制健康人血小板活化、黏附及聚集等功能，为三七花通过调控血小板功能，从而防治心脑血管疾病提供了新的理论依据和临床应用基础

实时荧光PCR同时检测金黄色葡萄球菌和大肠杆菌O157:H7

目的建立改良分子信标-双重实时荧光PCR同时检测金黄色葡萄球菌和大肠杆菌O157:H7,应用于细菌性食物中毒的快速诊断。方法根据GeneBank公布的金黄色葡萄球菌nuc基因序列和大肠杆菌O157:H7rfbE基因序列,设计引物和改良分子信标探针,建立改良分子信标-双重实时PCR检测体系。结果双重荧光PCR反应体系检测151株金黄色葡萄球菌和27株大肠杆菌O157:H7,均出现特异的荧光信号,两种细菌检测互不干扰。对8762份大便、食品等标本进行检测,315份标本金黄色葡萄球菌实时荧光PCR阳性,其中286份金黄色葡萄球菌培养阳性;31份标本大肠杆菌O157:H7实时荧光PCR阳性,其中26份大肠杆菌O157:H7培养阳性。从样品处理到检测结果仅需要时间2h~1d。结论改良分子信标-多重实时荧光PCR检测体系快速、灵敏度高,特异性强,可用于金黄色葡萄球菌和大肠杆菌O157:H7食物中毒的快速诊断和肠道传染病的初筛,为食源性疾病的分子流行病学调查提供新的检测手段

Preparation and biological safety of basic fibroblast growth factor/double-layered collagen composite

背景:胶原特殊的分子结构和生物活性有利于多种细胞黏附、增殖和分化,并可降解为新生组织提供足够空间。目的:制备一种复合负载碱性成纤维细胞生长因子的壳聚糖-肝素纳米粒子双层胶原基复合材料,并评价其生物安全性。方法:制备交联风干胶原膜和交联冻干胶原膜。将壳聚糖-肝素纳米粒滴于交联冻干胶原膜上,再将湿态交联风干胶原膜置于复合纳米粒子的交联冻干胶原膜上风干,即碱性成纤维细胞生长因子/双层胶原基复合材料。采用急性全身毒性试验、溶血试验、热原试验和细胞毒性试验评价其生物安全性。结果与结论:碱性成纤维细胞生长因子/双层胶原基复合材料为双层结构,一侧表面致密,另一侧疏松多孔。在其中间负载碱性成纤维细胞生长因子的壳聚糖-肝素纳米粒子呈不规则球形分布于胶原膜内侧面;急性全身毒性试验、热原试验、溶血试验均为阴性,细胞毒性为0级。说明碱性成纤维细胞生长因子/双层胶原基复合材料具有良好的生物安全性,对机体无毒,符合ISO10993-1评价标准。BACKGROUND: Collagen is a common used scaffold in tissue engineering, its specific molecular structure and biological activity are conducive to a variety of cell adhesion, proliferation and differentiation, and can speed up wound healing and degradation to provide sufficient space for new tissues.OBJECTIVE: To prepare a kind of inhomogeneous double layered collagen composite incorporated with basic fibroblast growth factor (bFGF) loaded chitosan-heparin (CS-Hep) nanoparticles, and to evaluate its biological safety.METHODS: The air-dried dense layer collagen membranes and freeze-dried loose layer collagen membrane were prepared respectively and then cross-linked by D-ribose (termed as CAM and CFM respectively).CS-Hep nanoparticles were prepared and then dropped on the surface of CFM.The wet CAM was laid on the surface of CFM with nanoparticles, and then air dried completely at 4 ℃.The obtained material was termed as bDM.Its physical and chemical properties were investigated.In addition, its bio-safety was also examined through acute systemic toxicity, pyrogen, hemolysis and cellular toxicity tests.RESULTS AND CONCLUSION: The bFGF/double-layered collagen composite was made up of double layers with one dense layer (CAM) and another loose layer (CFM).As part of bDM, CS-Hep nanopartiles with irregular global shape were aligned in the scope of D-period structure of the inner surface of CFM; the bFGF/double-layered collagen composite had no systemic acute toxicity, no cytotoxicity and pyrogen reactions as well as no hemolytic effect.The bFGF/double-layered collagen composite is prepared and found to have good biocompatibility and safety.Moreover, this material conforms to the ISO 10993-1, and can be used as a basic scaffold material in tissue engineering天津市科技支撑计划重点项目(08ZCKFSF02100);博士点基金项目(20101106110042)---