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支气管扩张剂治疗与哮喘死亡:病例对照研究

英国医学杂志中文版 2005年第4期8卷 220-222页

作者： H Ross Anderson jon g ayres Patricia M Sturdy J Martin Bland Barbara K Butland Clare Peckitt Jennifer C Taylor Christina R Victor 王同德（译）代华平（校） Department of Community Health Sciences St George＇s Hospital Medical School London SW17 ORE 不详

目的研究支气管扩张剂的应用与哮喘死亡的相关性。设计方法病例对照研究。研究设置英国33个卫生权威机构或卫生组织。研究对象532例年龄小于65岁而且死于哮喘的患者和532例对照病例,他们是与前者在住院日期、年龄和地区相匹配的哮喘住... 详细信息

目的研究支气管扩张剂的应用与哮喘死亡的相关性。设计方法病例对照研究。研究设置英国33个卫生权威机构或卫生组织。研究对象532例年龄小于65岁而且死于哮喘的患者和532例对照病例,他们是与前者在住院日期、年龄和地区相匹配的哮喘住院患者。主要结局指标应用比值比(OR)方法研究哮喘死亡与应用支气管扩张剂及其他治疗的相关性,同时对始发年龄、先前住院情况、相关的慢性阻塞性肺病(COPD)和其他种类药物进行校正,以分析这种相关性的敏感性。结果通过校正发现哮喘死亡与患者在过去4～12月内的用药无明显相关性,而与患者过去1～5年内吸入短效β2激动剂呈正相关(OR2.05,95%CI1.26～3.33),这种相关性主要表现在45～64岁年龄组,但与过去1～5年内使用抗生素呈负相关(0.59,0.39～0.89),这种负相关在45岁以下的患者表现更显著。年龄对各个时期的用药都有影响,在45岁以下年龄组口服类固醇激素与哮喘死亡呈负相关。哮喘死亡与患者过去1～5年内使用长效β2激动剂呈负相关,而与使用甲基黄嘌呤呈正相关,但它们无显著意义。结论没有证据显示中长期吸入长效β2激动剂有负面效应。短效β2激动剂与死亡呈正相关有多种解释,仅其中一项是它的直接负面效应。

关键词：支气管扩张剂药物治疗哮喘死亡甲基黄嘌呤短效β2激动剂

On the rate of convergence of the maximum likelihood estimator of a k-monotone density

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Science China Mathematics 2009年第7期52卷 1525-1538页

作者： WELLNER jon A Department of Statistics University of Washington

Bounds for the bracketing entropy of the classes of bounded k-monotone functions on [0,A] are obtained under both the Hellinger distance and the Lp(Q) distance,where 1 p < ∞ and Q is a probability measure on [0,A].Th... 详细信息

Bounds for the bracketing entropy of the classes of bounded k-monotone functions on [0,A] are obtained under both the Hellinger distance and the Lp(Q) distance,where 1 p gence of the maximum likelihood estimator of a k-monotone density.

关键词： bracketing metric entropy maximum likelihood estimator Hellinger distance 62g05 46B50

Varieties for Cohomology with Twisted Coefficients

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Acta Mathematica Sinica,English Series 1999年第1期15卷 81-92页

作者： jon F.Carlson Department of Mathemtics University of GeorgiaAthensGA 30602 USA

Let g be a finite group and k a field of characteristic p>*** this paper we consider the support variety for the cohomology module Extkg*（M,N） where M and N are *** is the subvariety of the maximal ideal spectrum of H*（g,k） of the annihilator of the cohomology module. For modules in the principal block we show that that the variety is contained in the intersections of the varieties of M and N and the difference between the that intersection and the support variety of the cohomology module is contained in the group theoretic *** other blocks a new nucleus is defined and a similar theorem is *** in the case of modules in a nonprincipal block several new difficulties are highlighted by some examples.

关键词： group Cohomology Support varieties Cohomological varieties Annihilators of cohomology

Functionalised Polymers by Surface Modification

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复旦学报（自然科学版） 2005年第5期44卷 772-773页

作者： jon-Paul griffiths M. g. Moloney Chemistry Research Laboratory Mansfield Rd University of OxfordOX 3TAUnited KingdomChemistry Research Laboratory Mansfield Rd University of OxfordOX 3TAUnited Kingdom

Surface-active polymers are of substantial importance in many diverse aspects of modern technology, with applications ranging from solid phase chemical synthesis related to drug discovery and chemical catalysis to biocompatible/bioactive medical implants and prostheses, and to surface-modified fabrics. Whilst there are a number of existing physical (e. g. corona or plasma discharge, ion beam irradiation[1] ) and chemical (e. ***, oxidation, chlorination, acylation and quaternisation[2-4]) methods for the surface modification of polymers, the frequent requirement for significant infrastructure, harsh reaction conditions, and limitation to specific polymer types (e. g. polybutadiene[5] ), which must possess suitable chemical functionality capable of direct modification, led us to consider alternative chemical methods. Desirable was an alternative that would be amenable to a large range of polymers, permitting direct chemical modification under mild conditions and using inexpensive reagents.

关键词：聚合体表面活性表面修复碳烯合成方法

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食品中农药残留的高通量分析之展望(英文)

色谱 2011年第7期29卷 587-593页

作者： jon W WONg Perry g WANg U.S. Food and Drug Administration Center for Food Safety and Applied NutritionOffice of Regulatory Science5100 Paint Branch ParkwayHFS-706College ParkMD 20740USA

The screening of pesticide residues plays a vital role in food *** of high throughput analytical procedures are desirable for screening a large number of pesticides and food samples in a time-efficient and cost-effective *** review discusses how sample throughput of pesticide analysis could be improved with an emphasis on sample preparation,instrumentation and data analysis.

关键词： pesticide analysis high throughput foods

Influence of in vitro capacitation time on structural and functional human sperm parameters

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Asian Journal of Andrology 2020年第5期22卷 447-453页

作者： Paula Saez-Espinosa Natalia Huerta-Retamal Laura Robles-gomez Manuel Aviles jon Aizpurua Irene Velasco Alejandro Romero Maria Jose gomez-Torres Department of Biotechnology Faculty of ScienceUniversity of AlicanteAlicante 03080Spain FISABI0-University Hospital of San Juan de Alicante Service of Gynecology and ObstetricsSan Juan de Alicante 03550Spain Departm ent of Cell Biology and Histology Faculty of MedicineUniversity of Murcia and IMIB-ArrixacaMurcia 30100Spain IVF Spain Reproductive MedicineAlicante 03540Spain University Hospital of San Juan de Alicante Service of Gynecology and ObstetricsSan Juan de Alicante 03550Spain Human Fertility Cathedra University of AlicanteAlicante 03080Spain.

A cascade of dramatic physiological events is linked to the sperm acrosome reaction and binding to the oocyte's zona pellucida during human sperm ***,structural and functional sperm changes during capacitation currently remain poorly ***,we performed a multibiomarker approach based on the utilization of sperm concentration,motility,viability,morphology,acrosome reaction,tyrosine phosphorylation,DNA fragmentation,and lectin-binding sites to analyze the impact caused by swim-up selection times(uncapacitated,1 h capacitated,and 4 h capacitated)on sperm function and structure in normozoospermic *** found that a 4 h swim-up capacitation increased sperm quality,because a large number of cells with normal morphology and lower DNA fragmentation rates were ***,the long-term capacitation induced a higher percentage of cells with tyrosine phosphorylation of the principal piece as well as a redistribution of lectin-binding ***,the multivariate biomarkers analyzed showed a less variable distribution on spermatozoa recovered after 4 h capacitation than that with the shorter capacitation *** findings stress the importance of capacitation time as a relevant factor in sperm quality with potential biological reproductive implications both for basic research and in assisted reproduction techniques.

关键词： acrosome reaction capacitation DNA fragmentation glycocalyx lectin-binding sites membrane integrity protein phosphorylation sperm selection

Combining in-situ water quality and remotely sensed data across spatial and temporal scales to measure variability in wet season chlorophyll-a:great Barrier Reef lagoon(Queensland,Australia)

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Ecological Processes 2013年第1期2卷 328-349页

作者： Michelle J Devlin Eduardo Teixeira da Silva Caroline Petus Amelia Wenger Daniel Zeh Dieter Tracey Jorge gÁlvarez-Romero jon Brodie Catchment to Reef Research group TropWaterJames Cook UniversityTownsvilleQLD4811Australia Australian Research Council Centre of Excellence for Coral Reef Studies James Cook UniversityTownsvilleQLDAustralia School of Marine and Tropical Biology James Cook UniversityTownsvilleQLDAustralia

Introduction:Combining in-situ data from single-point time series with remotely sensed spatial data allowed a greater elucidation of changes in chlorophyll-a concentrations through wet season conditions in the great Barrier Reef coastal ***:Single-point time-series data were collected from 2006 to 2012 during high river flow conditions to assess changes in phytoplankton biomass(measured as chlorophyll-a).Additionally,three flood plume water types,derived from classified true-colour Aqua moderate resolution imaging spectroradiometer(MODIS)images,were used to group single-point time-series data for the phytoplankton biomass ***:Survey data illustrate the heterogeneity of chlorophyll-a distribution over seasonal and inter-annual cycles and the difficulty in describing community responses through the wet *** spatial data demonstrate distinct regional differences throughout the great Barrier *** high chlorophyll-a concentrations measured in flood plume waters immediately adjacent to the inshore,highly turbid‘inner’flood plume are a product of sufficient light,given most of the suspended solids have settled from the plume,and the availability of sufficient nutrients,which drive higher phytoplankton production and characterise the formation of secondary stage flood *** formation and extent of these secondary flood plumes were mapped using MODIS true-colour satellite *** distance and the location of the secondary plume water are reliant on flow,coastal hydrodynamics,and biological ***:The combination of in-situ data and remotely sensed data provides information on the complexity of these coastal processes during the wet season and offers managers a more comprehensive understanding of the extent of nutrient enrichment in the great Barrier Reef coastal area and the potential influence of flood plumes on coastal marine ecosystems.

关键词： Chlorophyll-a great barrier reef Phytoplankton Monitoring Remote sensing MODIS

Digital zoology Version 2.0 CD-ROM and Student Workbook

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Batch Active Learning for Multispectral and Hyperspectral Image Segmentation Using Similarity graphs

2003年

作者： edit by jon g. Houseman

来源：畅想之星图书光盘版（南... 评论

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Communications on Applied Mathematics and Computation 2024年第2期6卷 1013-1033页

作者： Bohan Chen Kevin Miller Andrea L.Bertozzi jon Schwenk Department of Mathematics University of CaliforniaLos Angeles520 Portola PlazaLosAngeles90095CAUSA Oden Institute for Computational Engineering and Sciences University of Texas at Austin201 E 24th StAustin 78712TXUSA Los Alamos National Laboratory Los AlamosNM 87545USA

graph learning,when used as a semi-supervised learning(SSL)method,performs well for classification tasks with a low label *** provide a graph-based batch active learning pipeline for pixel/patch neighborhood multi-or hyperspectral image *** batch active learning approach selects a collection of unlabeled pixels that satisfy a graph local maximum constraint for the active learning acquisition function that determines the relative importance of each pixel to the *** work builds on recent advances in the design of novel active learning acquisition functions(e.g.,the Model Change approach in arXiv:2110.07739)while adding important further developments including patch-neighborhood image analysis and batch active learning methods to further increase the accuracy and greatly increase the computational efficiency of these *** addition to improvements in the accuracy,our approach can greatly reduce the number of labeled pixels needed to achieve the same level of the accuracy based on randomly selected labeled pixels.

关键词： Image segmentation graph learning Batch active learning Hyperspectral image