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Chinese Science Bulletin 2004年第11期49卷 1142-1145页

作者： shenzheng ZHAOxingxu CAOYujing BUShumin LIUWeimin DUANEnkui CollegeofVeterinaryMedicine GansuAgriculturalUniversityLanzhou730070China StateKeyLaboratoryofReproductiveBiology InstituteofZoologyChineseAcademyofSciencesBeijing100080China

Nitric oxide (NO) is a multifunctional messen-ger molecule produced through oxidation of L-arginine to L-citrulline by enzyme NO synthase (NOS). In the current study, mouse blastocysts were cultured in the different media, and the implantation capacity of blastocyst was evaluated by evaluating the percentage of embryos adhesion and out-growth after culture for 12, 24 or 48 h. Matrix metallopro-teinase-2 (MMP-2) mRNA was detected by RT-PCR, and MMP-2 protein was detected by gelatin zymography. Inhibi-tion of blastocyst adhesion and outgrowth was observed in embryo cultured with 500 mmol/L NOS inhibitor NG-mono- methyl-L-arginine (L-NMMA) alone; however, 100 mmol/L S-nitroso-Nacetylpenicillamine (SNAP), a NO donor, and 20 mmol/L cGMP analogue, 8-Br-cGMP could block this inhibi-tion. The expression and production of MMP-2 in the blas-tocysts were suppressed by L-NMMA, and SNAP or 8-br-cGMP could reverse this suppression. These results suggest that NO induces embryo implantation by cGMP sig-naling pathway.

关键词：基体金属蛋白酶一氧化氮循环鸟苷一磷酸盐粘附生长物植入胚胎

Occurrence of human pathogenic bacteria carrying antibiotic resistance genes revealed by metagenomic approach: A case study from an aquatic environment

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Journal of Environmental Sciences 2019年第6期31卷 248-256页

作者： Renjun Zhou shenzheng Zeng Dongwei Hou Jian Liu Shaoping Weng Jianguo He Zhijian Huang State Key Laboratory of Biocontrol Guangdong Provincial Key Laboratory of Marine Resources and Coastal Engineering School of MarineSciences Sun Yat-sen University School of Life Sciences Sun Yat-sen University

Antibiotic resistance genes(ARGs), human pathogenic bacteria(HPB), and HPB carrying ARGs are public issues that pose a high risk to aquatic environments and public health. Their diversity and abundance in water, intestine, and sediments of shrimp culture pond were investigated using metagenomic approach. A total of 19 classes of ARGs, 52 HPB species, and 7 species of HPB carrying ARGs were found. Additionally, 157, 104, and 86 subtypes of ARGs were detected in shrimp intestine, pond water, and sediment samples, respectively. In all the samples, multidrug resistance genes were the highest abundant class of ARGs. The dominant HPB was Enterococcus faecalis in shrimp intestine, Vibrio parahaemolyticus in sediments, and Mycobacterium yongonense in water, respectively. Moreover, E. faecalis(contig Intestine_364647)and Enterococcus faecium(contig Intestine_80272) carrying efr A, efr B and ANT(6)-Ia were found in shrimp intestine, Desulfosaricina cetonica(contig Sediment_825143) and Escherichia coli(contig Sediment_188430) carrying mex B and APH(3′)-IIa were found in sediments, and Laribacter hongkongensis(contig Water_478168 and Water_369477), Shigella sonnei(contig Water_880246),and Acinetobacter baumannii(contig Water_525520) carrying sul1, sul2, ere A, qac H, OXA-21, and mph D were found in pond water. Mobile genetic elements(MGEs) analysis indicated that horizontal gene transfer(HGT) of integrons, insertion sequences, and plasmids existed in shrimp intestine, sediment, and water samples, and the abundance of integrons was higher than that of other two MGEs. The results suggested that HPB carrying ARGs potentially existed in aquatic environments, and that these contributed to the environment and public health risk evaluation.

关键词： Antibiotic resistance genes Human pathogenic bacteria Mobile genetic elements Aquatic environment

Bacterial and eukaryotic community interactions might contribute to shrimp culture pond soil ecosystem at different culture stages

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Soil Ecology Letters 2022年第2期4卷 119-130页

作者： Renjun Zhou Hao Wang Dongdong Wei shenzheng Zeng Dongwei Hou Shaoping Weng Jianguo He Zhijian Huang State Key Laboratory of Biocontrol Southern Marine Sciences and Engineering Guangdong Laboratory(Zhuhai)School of Marine SciencesSun Yat-sen UniversityGuangzhou 510275China Institute of Aquatic Economic Animals and Guangdong Province Key Laboratory for Aquatic Economic Animals School of Life SciencesSun Yat-sen UniversityGuangzhou 510275China

Sedimentary bacterial and eukaryotic communities are major components of the aquatic *** the linkages between their community structure and interactions is crucial to understand the diversity and functions of aquatic and soil ***,how their diversity and assembly contribute to their interactions on time scale is *** study examined sedimentary bacterial and eukaryotic communities in shrimp culture ponds at different culture *** most abundant bacteria were Proteobacteria(38.27%),whereas the most abundant eukaryotes were Chytridiomycota(27.48%).Bacterial and eukaryotic diversities were correlated(P<0.05),implying the strong interactions between bacteria and *** showed that the bacterial and eukaryotic communities became increasingly similar on a local scale along with the shrimp *** the eukaryotic community significantly increased in similarity along with the shrimp culture(P<0.05),suggesting that the sedimentary eukaryotic community structure is sensitive under shrimp ***-occurrence network modeling indicated that positive microbial interactions were *** homogeneous selection was the major driver of community *** diversity negatively correlated with operational taxonomic units and positive links in networks(P<0.05),whereas eukaryotic diversities positively correlated with positive links in networks(P<0.05).This study broadens our knowledge about sedimentary microbial diversity,community assembly,and interaction patterns on time scale,providing a reference for the sustainable management in aquaculture production.

关键词： Sediment Shrimp culture Bacteria Eukaryotes Microbial community

Preparation of Biodegradable Microspheres of Testosterone with Poly（D,L-lactide-co-glycolide） and Test of Drug Release in vitro

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浙江省医学科学院学报 2005年第2期16卷 242-245页

作者： shenzheng-rong ZhuJia-hui MaZhen WangFang WangZun-yuan InstituteofMateriaMedica.ZhejiangAcademyofMedicalSciences Hangzhou310013

Biodegradable microspheres formulation of testosterone (T)can be used as a new physiological approach for androgen replacement in hypogonadal *** this study, poly(D, L-lactide-co-glycolide)(PLGA)microspheres containing T were prepared by a solvent-evaporation/solvent-diffusion process and the drug release tests of the microspheres were carried out in vitro.T/PLGA microspheres with good yield,desired size and satisfied drug loading were obtained.A significant testosterone sustained release was shown in the drug release tests in *** PLGA microspheres preparations are normally sterilized by colbat-60 *** effects of 25 kGy colbat-60 irradiation on physicochemical properties and in vitro drug release profile of T/PLGA microsphere were investigatedphysicochemical propertiesd. The results showed that the irradiation didn't have any effects on the of *** about one-third decrease in molcoulaar weight of PLGA was caused by the irradiation, no significant changes were observed on the drug release profile in vitro.

关键词：生物降解微球体睾丸激素聚乙烯药物释放

热处理工艺对建筑用490 MPa级耐火钢力学性能的影响

维普期刊数据库评论

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粉末冶金材料科学与工程 2019年第3期24卷 220-225页

作者：陈俊罗恒勇林申正宜宾职业技术学院

研究不同正火温度下 NSFR490 耐火钢的显微组织与力学性能。结果表明,正火处理温度在 730~820 ℃区间内,耐火钢的强度随温度升高而下降,但仍可满足工程应用的标准要求,且塑性得以提高(伸长率由 20%升至 26%)。在 600 ℃进行拉伸试验,结... 详细信息

研究不同正火温度下 NSFR490 耐火钢的显微组织与力学性能。结果表明,正火处理温度在 730~820 ℃区间内,耐火钢的强度随温度升高而下降,但仍可满足工程应用的标准要求,且塑性得以提高(伸长率由 20%升至 26%)。在 600 ℃进行拉伸试验,结果满足高温屈服强度大于室温屈服强度 2/3 的要求。耐火钢经过 600 ℃高温回火工艺,显微组织整体变化不大,仅晶粒尺寸略有长大,这与耐火钢在高温下的力学性能(屈服强度由 315 MPa降至 292 MPa)表现一致。最后结合该耐火钢的实际工程应用,利用 ANSYS 软件对其进行结构失稳临界温度计算,获得了该材料的位移温度曲线,并得出其失效临界温度点为 620 ℃。

关键词：耐火钢热处理显微组织力学性能有限元

学校课间(操)体育活动存在的问题及改革思路

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体育学刊 2002年第4期9卷 95-96页

作者：向阳罗湖中学体育组广东深圳518038

课间 (操 )体育活动是学校体育的重要组成部分 ,但长期以来大多是流于形式、组织管理松散 ,实际效果不大。在分析的基础上提出课间 (操 )体育活动要加强管理、改变形式等建议。

关键词：学校体育课间(操)体育活动体育改革

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社会工作在医德医风建设领域的介入研究

社会工作 2008年第22期 60-62页

作者：陈碧瑶深圳市福田区人民医院广东深圳518033

在市场经济环境下,医院的医德医风建设对于缓解医患矛盾,建立良好的医患关系显得非常重要。以往的医德医风建设往往是靠传统的政治思想工作来实现的。本文通过对我国目前医院政治思想工作的分析,研究医院政治思想工作中存在的不足和缺陷... 详细信息

在市场经济环境下,医院的医德医风建设对于缓解医患矛盾,建立良好的医患关系显得非常重要。以往的医德医风建设往往是靠传统的政治思想工作来实现的。本文通过对我国目前医院政治思想工作的分析,研究医院政治思想工作中存在的不足和缺陷,提出以社会工作为抓手,通过党团的项目建设,以组织吸纳资源,为创新医德医风建设的新模式做思考。

关键词：医德医风建设社会工作组织资源

基于PIRD-CNN的航空发动机轴承故障诊断方法研究

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振动与冲击 2024年第18期43卷 201-207,231页

作者：张搏文庞新宇程宝安李峰宿绅正国营四达机械制造公司陕西咸阳610400 太原理工大学机械与运载工程学院太原030024 太原理工大学航空航天学院太原030024

航空发动机结构与系统的复杂性导致轴承的故障诊断方法通常面临特征提取与模式识别的困难。针对以上不足,考虑实际工程诊断的实时性与准确性,提出了一种新的基于转子位移概率密度信息(probability density information of rotor displac... 详细信息

航空发动机结构与系统的复杂性导致轴承的故障诊断方法通常面临特征提取与模式识别的困难。针对以上不足,考虑实际工程诊断的实时性与准确性,提出了一种新的基于转子位移概率密度信息(probability density information of rotor displacement,PIRD)的航空发动机轴承智能故障诊断方法。其主要对一维卷积神经网络(1-dimensional convolutional neural network,1DCNN)模型进行改进,在传统的卷积层前面增加了PIRD的提取层,可以提取转子振动位移信号的概率密度信息,有效地降低了数据的冗余度,同时保留了故障监测的重要指标。提出的PIRD-CNN诊断模型保留了1DCNN端到端的故障诊断优势,将该模型在航空发动机试验台产生的轴承故障数据进行测试,其对轴承故障诊断精度可达96.58%,与基准研究相对比表明,PIRD-CNN能够快速且更加精准地诊断航空发动机轴承的故障。

关键词：航空发动机轴承转子位移概率密度信息(PIRD) 卷积神经网络故障诊断

BIM技术和神经网络相融合的装配式建筑成本控制研究

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建筑经济 2021年第2期42卷 86-89页

作者：林申正罗恒勇重庆大学木工程学院重庆400044 宜宾职业技术学院建筑与环境学院四川宜宾644000

为了高效、准确地实现装配式建筑成本控制,提出BIM技术和神经网络相融合的装配式建筑成本控制方法。首先通过BIM技术对建筑实施建模,并导出各项几何造价信息,根据估价指标和造价软件得到初步测算结果,然后将所得结果输入BP神经网络进行... 详细信息

为了高效、准确地实现装配式建筑成本控制,提出BIM技术和神经网络相融合的装配式建筑成本控制方法。首先通过BIM技术对建筑实施建模,并导出各项几何造价信息,根据估价指标和造价软件得到初步测算结果,然后将所得结果输入BP神经网络进行学习,并引入遗传算法优化神经网络的权值、阈值,建立装配式建筑成本控制模型。根据模型的预测结果对装配式建筑成本进行优化,最后进行仿真对比实验,结果表明:相对于对比方法,所提出方法的建筑成本预测精度更高。

关键词： BIM技术神经网络装配式建筑成本控制遗传算法优化控制

Theoretical　Analysis　and　Experimental　Research　on　Recordable　Compact　Disc　with　Dye　Material

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Chinese Journal of Lasers 1996年第2期 173-177页

作者： WANG Shiyong WANG Shijie (SAST DOD Co. Ltd.,shenzheng 518029, China)ZHANG Huier(Shanghai Institute of Techics and Physics, Shanghai 200083, China)

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ＴｈｅｏｒｅｔｉｃａｌＡｎａｌｙｓｉｓａｎｄＥｘｐｅｒｉｍｅｎｔａｌＲｅｓｅａｒｃｈｏｎＲｅｃｏｒｄａｂｌｅＣｏｍｐａｃｔＤｉｓｃｗｉｔｈＤｙｅＭａｔｅｒｉａｌ￥ＷＡＮＧＳｈｉｙｏｎｇ；ＷＡＮＧＳｈｉｊｉｅ（ＳＡＳＴＤＯＤＣｏ．Ｌｔｄ．，Ｓｈｅｎｚｈ...

关键词： recordable compact disc organic dye spin-coating