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Comparative quantification of human intestinal bacteria based on cPCR and LDR/LCR

World Journal of Gastroenterology 2012年第3期18卷 268-274页

作者： Zhou-Rui Tang Kai Li Yu-Xun Zhou zhen-xian xiao Jun-Hua xiao Rui Huang Guo-Hao Gu College of Chemistry Chemical Engineering and Biotechnology Donghua University Shanghai 201620 China State Key Laboratory of Bioreactor Engineering East China University of Science and Technology Shang hai 200237 China Department of Pre-Clinical Medicine School Soochow University Suzhou 215123 Jiangsu Prov ince China

AIM: To establish a multiple detection method based on comparative polymerase chain reaction (cPCR) and ligase detection reaction (LDR)/ligase chain reaction (LCR) to quantify the intestinal bacterial components. METHODS: Comparative quantification of 16S rDNAs from different intestinal bacterial components was used to quantify multiple intestinal bacteria. The 16S rDNAs of different bacteria were amplified simultaneously by cPCR. The LDR/LCR was examined to actualize the genotyping and quantification. Two beneficial (Bifidobacterium , Lactobacillus ) and three conditionally pathogenic bacteria (Enterococcus , Enterobacterium and Eubacterium ) were used in this detection. With cloned standard bacterial 16S rDNAs, standard curves were prepared to validate the quantitative relations between the ratio of original concentrations of two templates and the ratio ofthe fluorescence signals of their final ligation products. The internal controls were added to monitor the whole detection flow. The quantity ratio between two bacteria was tested. RESULTS: cPCR and LDR revealed obvious linear correlations with standard DNAs, but cPCR and LCR did not. In the sample test, the distributions of the quantity ratio between each two bacterial species were obtained. There were significant differences among these distributions in the total samples. But these distributions of quantity ratio of each two bacteria remained stable among groups divided by age or sex. CONCLUSION: The detection method in this study can be used to conduct multiple intestinal bacteria genotyping and quantification, and to monitor the human intestinal health status as well.

关键词： 16s rDNA Comparative quantification Com- parative polymerase chain reaction Intestinal bacteria Ligase chain reaction Ligase detection reaction

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针叶树理论材积式的适用性研究

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华北农学报 2004年第F12期19卷 50-55页

作者：王铁牛郑小贤田格日勒内蒙古农业大学林学院内蒙古呼和浩特010019 北京林业大学资源环境学院北京100083

研究以河北塞罕坝人工落叶松795株、内蒙古的苏格河人工落叶松45株、红花尔基沙地天然次生樟子松49株、那日斯太山地人工樟子松20株为例,对日本井上昭夫、黑川泰亨推导出的针叶树理论材积式进行适用性验证。从理论材积式和经验材积式计... 详细信息

研究以河北塞罕坝人工落叶松795株、内蒙古的苏格河人工落叶松45株、红花尔基沙地天然次生樟子松49株、那日斯太山地人工樟子松20株为例,对日本井上昭夫、黑川泰亨推导出的针叶树理论材积式进行适用性验证。从理论材积式和经验材积式计算的材积与实际材积之间的误差和精确度来看,理论材积式优于经验材积式。从而,进一步证明了理论材积式的适用范围的广泛性。

关键词：理论材积式经验材积式落叶松柿子松

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A promising approach for quantifying focal stroke modeling and assessing stroke progression:optical resolution photoacoustic microscopy photothrombosis

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Neural Regeneration Research 2025年第7期20卷 2029-2037页

作者： xiao Liang Xingping Quan xiaorui Geng Yujing Huang Yonghua Zhao Lei Xi zhen Yuan Ping Wang Bin Liu Faculty of Health Sciences University of MacaoMacao Special Administrative RegionChina Center for Cognitive and Brain Sciences University of MacaoMacao Special Administrative RegionChina Department of Biomedical Engineering Southern University of Science and TechnologyShenzhenGuangdong ProvinceChina State Key Laboratory of Quality Research in Chinese Medicine Institute of Chinese Medical SciencesUniversity of MacaoTaipaMacao Special Administrative RegionChina Department of Emergency Zhujiang HospitalSouthern Medical UniversityGuangzhouGuangdong ProvinceChina

To investigate the mechanisms underlying the onset and progression of ischemic stroke,some methods have been proposed that can simultaneously monitor and create embolisms in the animal cerebral ***,these methods often require complex systems and the effect of age on cerebral embolism has not been adequately studied,although ischemic stroke is strongly *** this study,we propose an optical-resolution photoacoustic microscopy-based visualized photothrombosis methodology to create and monitor ischemic stroke in mice simultaneously using a 532 nm pulsed *** observed the molding process in mice of different ages and presented age-dependent vascular embolism ***,we integrated optical coherence tomography angiography to investigate age-associated trends in cerebrovascular variability following a *** imaging data and quantitative analyses underscore the differential cerebrovascular responses to stroke in mice of different ages,thereby highlighting the technique's potential for evaluating cerebrovascular health and unraveling age-related mechanisms involved in ischemic strokes.

关键词： age-dependent cerebral cortex ischemic stroke mouse model optical coherence tomography angiography photoacoustic microscopy photothrombosis vascular imaging

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呼伦贝尔生态环境遥感调查和驱动力分析

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遥感信息 2006年第3期28卷 36-39,i0004页

作者：宁镇亚刘东兰郑小贤张峰北京林业大学省部共建森林培育与保护教育部重点实验室北京100083 国家环保总局小卫星筹备办公室北京100029

针对典型区的生态遥感监测的需要,采用RS、GIS一体化信息提取技术和数理统计方法,对呼伦贝尔地区进行了森林-草原生态交错带多时相遥感数据分析研究,揭示了研究区土地覆盖和生态要素结构变化、生态脆弱特征及时空分布规律,并以量化和可... 详细信息

针对典型区的生态遥感监测的需要,采用RS、GIS一体化信息提取技术和数理统计方法,对呼伦贝尔地区进行了森林-草原生态交错带多时相遥感数据分析研究,揭示了研究区土地覆盖和生态要素结构变化、生态脆弱特征及时空分布规律,并以量化和可视化的形式反映了该地区生态环境现状及其变化。结果表明,近16年来该地区的生态质量在不断下降,草地退化和荒漠化的范围在扩大,生态环境形势严峻。人口增长和超载放牧是土地利用变化的主要原因。

关键词：遥感森林草原交错带生态环境呼伦贝尔

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船用微型锅炉非线性温度系统控制器仿真与研究

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船海工程 2009年第4期38卷 80-83页

作者：刘宪珍毛小兵青岛港湾职业技术学院商船系山东青岛266404

为了实现对船用微型锅炉高、低水温的控制,在Matlab环境下对实测和计算的数据进行曲线拟合,建立了船用微型锅炉水温系统的非线性数学模型。运用滑模变结构控制理论,选取线性切换面和比例型趋近率,设计了一种滑模控制器,实现了双输入双... 详细信息

为了实现对船用微型锅炉高、低水温的控制,在Matlab环境下对实测和计算的数据进行曲线拟合,建立了船用微型锅炉水温系统的非线性数学模型。运用滑模变结构控制理论,选取线性切换面和比例型趋近率,设计了一种滑模控制器,实现了双输入双输出非线性耦合温度系统的解耦和控制。通过Matlab/Simulink软件的仿真,结果显示滑模变结构控制算法对非线性系统的控制有响应快、超调小、调节时间短、无误差和抖动的特点。

关键词：曲线拟合非线性滑模变结构组态王原型代码

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胰胆合流异常胆汁和血清淀粉酶的二维电泳

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复旦学报（医学版） 2005年第1期32卷 79-82页

作者：龚振华肖现民徐绍英张祥民上海交通大学附属上海市儿童医院外科 200040 复旦大学附属儿科医院外科上海200032 复旦大学化学系上海200433

目的通过二维电泳分析胰胆合流异常(PBM)患者的胆汁和血清淀粉酶的等电点和相对分子质量 (Mr)。方法通过醋酸纤维素薄膜电泳,将正常人血清和PBM患者胆汁和血清中淀粉酶初步分离提纯,继经等电聚焦和SDS-PAGE二维电泳,测定淀粉酶同工酶... 详细信息

目的通过二维电泳分析胰胆合流异常(PBM)患者的胆汁和血清淀粉酶的等电点和相对分子质量 (Mr)。方法通过醋酸纤维素薄膜电泳,将正常人血清和PBM患者胆汁和血清中淀粉酶初步分离提纯,继经等电聚焦和SDS-PAGE二维电泳,测定淀粉酶同工酶的Mr和等电点。结果在醋酸纤维素薄膜电泳中,淀粉酶泳动在γ球蛋白负极侧,显示出2条谱带。在二维电泳中,正常人血清淀粉酶的2个同工酶分别是等电点 p16.4(Mr≈54×103)和等电点p16.7(Mr≈55×103)的两个点:PBM患者胆汁和血清中,存在6个淀粉酶同工酶点,除了上述正常人血清淀粉酶的两个主要点之外,在p16.8和p17.2分别出现Mr≈55×103两个新点,在p16. 0和p16.2分别出现Mr≈53×103-54×103的两个新点。结论在PBM患者胆汁和血清中,淀粉酶存在6种同工酶,这一系列同工酶的Mr都接近正常的55×103,而等电点分布在p16.0到p17.2之间的6个点上,而正常人血清淀粉酶只存在两种同工酶。

关键词：胆汁正常人患者人血清血清淀粉酶淀粉酶同工酶二维电泳等电点等电聚焦 SDS-PAGE

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大比例浅水矩形水箱振动台试验研究及TLD等效线性化分析

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工程力学 2025年第1期42卷 143-151页

作者：肖从真巫振弘陈凯唐意严亚林中国建筑科学研究院有限公司北京100013 国家建筑工程技术研究中心北京100013

调谐液体阻尼器(TLD)是高层建筑减振的有效措施。该文进行了大比例浅水矩形水箱振动台试验研究，分析了将调谐液体阻尼器按等效线性化等效为单自由度系统的可行性。采用振动台试验得到目标水箱在0.6倍~1.4倍水体自振频率简谐激励荷载下... 详细信息

调谐液体阻尼器(TLD)是高层建筑减振的有效措施。该文进行了大比例浅水矩形水箱振动台试验研究，分析了将调谐液体阻尼器按等效线性化等效为单自由度系统的可行性。采用振动台试验得到目标水箱在0.6倍~1.4倍水体自振频率简谐激励荷载下，水体稳态振动时的水箱反力和频响函数;测量不同振动幅度下，水体的自振频率偏差;由水体自由振动衰减，测得5种不同网栅条件下的附加阻尼比;将风和地震荷载下某249 m高楼顶加速度作为水箱激励进行振动台混合试验，实测水箱反力和滞回曲线，并与等效线性化模型计算结果进行对比。结果表明，以最大变形割线刚度作为等效刚度、按等能量方法确定阻尼比的等效线性化模型基本可行，在简谐波和风荷载作用下较符合试验结果，在地震荷载下存在一定偏差。试验结果可为类似调谐液体阻尼器设计提供依据。

关键词：高层结构调谐液体阻尼器振动台试验附加阻尼比浅水水箱等效线性化

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Time-Dependent Analysis of High-Gain Triggering in Semi-insulating GaAs Photoconductive Switches

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Chinese Physics Letters 2001年第11期18卷 1479-1480页

作者： SHI Wei ZHAO Wei LIANG zhen-xian SUN xiao-Wei Applied Physics Department Xi'an University of TechnologyXi'an 710048 State Key Laboratory of Transient Optics and Technology Xi'an 710068 School of Electrical Engineering Xi'an Jiaotong UniversityXi'an 710049 Division of Microelectronics Nanyang Technological UniversitySingapore 639798

The transient transport of photo-generated carriers and temporal variation of the built-in field, during triggering in semi-insulating GaAs photoconductive switches, have been investigated by using a special Monte Carlo particle simulator. It shows that the built-in field can exceed the intrinsic avalanche field of semi-insulating GaAs under certain optical and electrical conditions. In such a case, local breakdown ionization is considered to be responsible for the transition in GaAs high-gain switching. The optical and electrical triggering thresholds are calculated and the calculated values of optical and electrical thresholds and partial delay time are in agreement with the published experimental data.

关键词： breakdown optical electrical

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Effect of Aging on Hardening Behavior of 15-5 PH Stainless Steel

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Journal of Iron and Steel Research International 2015年第7期22卷 607-614页

作者： Xin-yuan PENG xian-liang ZHOU xiao-zhen HUA zhen-wei WEI Hua-ying LIU School of Materials Science and Technology Nanjing University of Aeronautics and Astronautics School of Materials Science and Engineering Nanchang Hangkong University Key Laboratory for Microstructural Control of Metallic Materials of Jiangxi Province

Microstructure transformation and aging hardening behavior of 15-5 PH stainless steel were studied by optical microscopy （OM）, X-ray diffraction （XRD） and transmission electron microscopy （TEM）. The results showed that the 15-5 PH stainless steel consists of NbC precipitates and lath matensite with a high dislocation density after solution treatment. With increasing aging temperature and aging time, the martensitic laths were resolved gradually. Meanwhile, the nanometric-sized Cu precipitates gradually coarsened and lost their coherency with＇the martensite matrix, which exhibited an elliptical shape finally. Fine Cu precipitates can lead to significant dispersion hardening effect, while the coarsened Cu precipitates have no contribution to strengthening. The reversed austenite was observed in the speci- mens aged at 550 ℃ and above; moreover, the amount of reversed austenite increased as aging temperature in- creased. The precipitation hardening behavior of 15-5 PH stainless steel may depend on the balance between the softening caused by the formation of reversed austenite and the hardening caused by the precipitation of copper.

关键词： 15-5 PH stainless steel Cu precipitate reversed austenite aging hardening behavior

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Regulation of anti-Mullerian hormone(AMH)in males and the associations of serum AMH with the disorders of male fertility

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Asian Journal of Andrology 2019年第2期21卷 109-114页

作者： Hui-Yu Xu Hong-xian Zhang zhen xiao Jie Qiao Rong Li Center for Reproductive Medicine Department of Obstetrics and GynecologyPeking University Third HospitalBeijing 100191China Key Laboratory of Assisted Reproduction Ministry of EducationBeijing 100191China National Clinical Research Center for Obstetrics and Gynecology Beijing 100191China Beijing Key Laboratory of Reproductive Endocrinology and Assisted Reproductive Technology Beijing 100191China Department of Urology Peking University Third HospitalBeijing 100191China Department of Reproductive Endocrinology Zhejiang Provincial People's HospitalHangzhou Medical CollegeHangzhou 310014China

Anti-Mullerian hormone(AMH)is a functional marker of fetal Sertoli *** germ cell number in adults depends on the number of Sertoli cells produced duri ng peri natal *** ntly,AMH has received increasi ng attenti on in research of disorders related to male *** paper reviews and summarizes the articles on the regulation of AMH in males and the serum levels of AMH in male fertility-related *** have determined that follicle-stimulating hormone(FSH)promotes AMH transcription in the absenee of androgen *** inhibits the transcriptional activation of *** undetectable levels of serum AMH and testosterone levels indicate a lack of functional testicular tissue,for example,that in patients with anorchia or severe Klinefelter syndrome suffering from impaired *** normal serum testosterone level and undetectable AMH are highly suggestive of persistent Mullerian duct syndrome(PMDS),combined with clinical *** levels of both AMH and testosterone are always subnormal in patients with mixed disorders of sex development(DSD).Mixed DSD is an early-onset complete type of disorder with fetal hypogonadism resulting from the dysfunction of both Leydig and Sertoli *** AMH levels are varying in patients with male fertility-related disorders,in cludi ng pubertal delay,severe con genital hypog on adotropic hypogonadism,nonobstructive azoospermia,Klinefelter syndrome,varicocele,McCune-Albright syndrome,and male senescence.

关键词： anti-Mullerian hormone disorders related to male fertility follicle-stimulating hormone testosterone

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