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Bone Research 2020年第1期8卷 14-25页

作者： j.son TWan douglas MSheeley Martha j.omerman j.nice SLee National Institute of Dental and Craniofacial Research National Institutes of HealthBethesdaMDUSA Laboratory for Oral Connective Tissue Biology National Institute of Arthritis and Musculoskeletal and Skin DiseasesNational Institutes of HealthBethesdaMDUSA

It is well established that alterations in phosphate metabolism have a profound effect on hard and soft tissues of the oral cavity. The present-day clinical form of osteonecrosis of the j.w(ONj. was preceded by phosphorus necrosis of the j.w, ca. 1860. The subsequent removal of yellow phosphorus from matches in the early 20 th century saw a parallel decline in "phossy j.w" until the early 2000 s, when similar reports of unusual j.w bone necrosis began to appear in the literature describing j.w necrosis in patients undergoing chemotherapy and concomitant steroid and bisphosphonate treatment. Today, the potential side effect of ONj.associated with medications that block osteoclast activity(antiresorptive) is well known, though the mechanism remains unclear and the management and outcomes are often unsatisfactory. Much of the existing literature has focused on the continuing concerns of appropriate use of bisphosphonates and other antiresorptive medications, the incomplete or underdeveloped research on ONj. and the use of drugs with anabolic potential for treatment of osteoporosis. While recognizing that ONj.is a rare occurrence and ONj.associated medications play an important role in fracture risk reduction in osteoporotic patients, evidence to date suggests that health care providers can lower the risk further by dental evaluations and care prior to initiating antiresorptive therapies and by monitoring dental health during and after treatment. This review describes the current clinical management guidelines for ONj. the critical role of dental-medical management in mitigating risks, and the current understanding of the effects of predominantly osteoclast-modulating drugs on bone homeostasis.

关键词： drugs metabolism alterations

Biodegradable stent or balloon dilatation for benign oesophageal stricture: Pilot randomised controlled trial

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World j.urnal of Gastroenterology 2014年第48期20卷 18199-18206页

作者： Anj.n Dhar Helen Close Yirupaiahgari K Viswanath Colin j.Rees Helen C Hancock A Deepak Dwarakanath Rebecca H Maier douglas Wilson j.mes M Mason Department of Gastroenterology County Durhamand Darlington NHS Foundation Trust Co. Durham DL14 6ADUnited Kingdom Durham Clinical Trials Unit School of Medicine Pharmacy and Health Durham University Queen’s Campus Wolfson Research Institute University Boulevard Stockton-on-Tees TS17 6BH United Kingdom Department of Surgery James Cook University Hospital Marton Road Middlesbrough TS4 3BW United Kingdom Department of Gastroenterology South Tyneside Hospitals NHS Foundation Trust Harton Lane South Shields NE34 0PL United Kingdom Department of Gastroenterology University Hospitals of North Tees Hardwick Stockton on Tees TS19 8PE United Kingdom

AIM: To undertake a randomised pilot study comparing biodegradable stents and endoscopic dilatation in patients with strictures.

关键词： Benign oesophageal stricture Biodegradable stent Endoscopic balloon dilatation Pilot study Randomised controlled trial Dysphagia

Ectomycorrhizal and Saprotrophic Fungal Communities Vary Across mm-Scale Soil Microsites Differing in Phosphatase Activity

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Pedosphere 2019年第3期29卷 344-359页

作者： Aaron GODIN Denise BROOKS Sue j. GRAYSTON Melanie D. j.NES Biology Department University of British Columbia Okanagan campus Kelowna V1V 1V7 (Canada) Department of Forest & Conservation Sciences Faculty of Forestry University of British Columbia Vancouver V6T 1Z4 (Canada)

To understand nutrient cycling in soils, soil processes and microorganisms need be better characterized. To determine whether specific trophic groups of fungi are associated with soil enzyme activity, we used soil imprinting to guide mm-scale sampling from microsites with high and low phosphatase activities in birch/douglas-fir stands. Study 1 involved sampling one root window per site at 12 sites of different ages(stands);study 2 was conducted at one of the stem-exclusion stands, at which 5 root windows had been installed. Total fungal and ectomycorrhizal(EM) fungal terminal-restriction fragment length polymorphism(TRFLP)fingerprints differed between high-and low-phosphatase activity microsites at 8 of 12 root windows across 12 sites. Where differences were detected, fewer EM fungi were detected in high-than low-phosphatase activity microsites. Using 5 root windows at one site,next-generation sequencing detected similar fungal communities across microsites, but the ratio of saprotrophic to EM fungal reads was higher in high-phosphatase activity microsites in the two windows that had low EM fungal richness. In windows with differences in fungal communities, both studies indicated that EM fungi were less successful than saprotrophic fungi in colonizing fine-scale,organic matter-rich microsites. Fine-scale sampling linked with in situ detection of enzyme activity revealed relationships between soil fungal communities and phosphatase activity that could not be observed at the scales employed by conventional approaches, thereby contributing to the understanding of fine-scale phosphorus cycling in forest soils.

关键词： ectomycorrhizae fine scale fungal communities phosphatase root windows saprotrophic fungi soil imprinting

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Status of IPC-4101F

Status of IPC-4101F

第十八届中国覆铜板技术·市场研讨会

作者： douglas j.Sober Microtek Changzhou Laboratories

The publication of IPC-4101E released in March 2017 has introduced a tightened definition of contamination that is allowed for copper-clad laminates and prepregs. Otherwise the changes in this revision are minimal. For IPC-4101 Revision F, there are a number of changes that will affect CCL makers world-wide including new specification sheets, introduction of FR-15.0 and FR-15.1, and the new IPC Validation Services certification program. As a primary contributor to IPC-4101 and the Base Materials General Chairman for IPC, Mr. Sober will provide details of these standards and how they will affect the electronics supply chain.

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GPS二次差数据分析

天文学报 1990年第1期31卷 15-26页

作者：庄奇祥 R.j.douglas 中国科学院上海天文台 Lab. for Basic Standaras Division of Physics National Research Council Canada

根据在加拿大国家研究院(NRC),美国国家标准局(NBS)和美国海军天文台(USNO)之间通过不同GPS卫星和不同跟踪时间的共视测量数据,计算和分析了"一般二次差"和"时刻间二次差"观测量.借助于一些有意义的结果,人们可以加深对GPS各项误差源的... 详细信息

根据在加拿大国家研究院(NRC),美国国家标准局(NBS)和美国海军天文台(USNO)之间通过不同GPS卫星和不同跟踪时间的共视测量数据,计算和分析了"一般二次差"和"时刻间二次差"观测量.借助于一些有意义的结果,人们可以加深对GPS各项误差源的认识.本文提出了利用单通道接收机得到"卫星间二次差"的"伪同步"方法,并建议了一种把两台站间所有时间比对共视测量数据结合在一起的无偏差权平均计算方法.

关键词： GPS共视法差分观测量 GPS测量测量误差二次差 “伪同步”法

Endocrine correlates of mate choice and promiscuity in females of a socially monogamous avian mating system with alternative male reproductive phenotypes

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Current Zoology 2014年第6期60卷 804-815页

作者： Hubert SCHWABL Willow R. LINDSAY douglas G. BARRON Michael S. WEBSTER School of Biological Sciences and Center for Reproductive Biology Washington State University Pullman WA 99164-4236 USA Department of Department of Biological and Environmental Sciences Goteborg University Box 463405 30 Goteborg Sweden Department of Psychology University of South Florida Tampa FL 33620-7200 USA Department of Neurobiology and Behavior and Comell Laboratory for Ornithology Comell University Ithaca NY 14850 USA

While our understanding of male reproductive strategies is informed by extensive investigations into endocrine mechanisms, the proximate mechanisms by which females compete for mates and adj.st reproduction to social environment remains enigmatic. We set out to uncover endocrine correlates of mate choice, social environment, and reproductive investment in female red-backed fairy-wrens Malurus melanocephalus. In this socially monogamous, yet highly sexually promiscuous species, females experience discrete variation in the phenotype of their mates, which vary in both plumage signals and level of paternal care, and in the composition of their breeding groups, which consist of either the pair alone or with an additional cooperative auxiliary; fe- male investment varies according to these social parameters. We found that androgen, estrogen, and glucorticoid levels varied with reproductive stage, with highest androgen and estrogen concentrations during nest construction and highest corticosterone concentrations during the pre-breeding stage. These stage-dependent patterns did not vary with male phenotype or auxiliary presence, though androgen levels during pre-breeding mate selection were lower in females obtaining red/black mates than those obtaining brown mates. We found no evidence that androgen, estrogen, or corticosterone levels during the fertile period were re- lated to extra-pair young （EPY） frequency. This study demonstrates clear changes in steroid levels with reproductive stage, though it found little support for variation with social environment. We suggest hormonal responsiveness to social factors may be physiologically constrained in ways that are bypassed through exogenous hormone manipulations.

关键词： Androgen Estrogen Glucocorticoid Mate choice Promiscuity Alternative phenotypes

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IC先导开发向批量生产的技术转移

微电子学 1988年第5期18卷 80-85页

作者： douglas j. Welter 成福康莫托洛拉双极工艺中心

硅片加工工艺从研究小组转移到批量生产阶段,必须按几条指导原则来计划进行。

关键词：批量生产加工工艺小组成批生产加工技术硅片技术转移 IC

Interfacial Charge Transfer in Nanoscale Polymer Transistors

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Nano Research 2008年第4期1卷 341-350页

作者： j.ffrey H.Worne Raj.v Giridharagopal Kevin F.Kelly douglas Natelson Department of Electrical and Computer Engineering Rice University6100 Main St.HoustonTX 77005USA Department of Physics and Astronomy Rice University6100 Main St.HoustonTX 77005USA

Interfacial charge transfer plays an essential role in establishing the relative alignment of the metal Fermi level and the energy bands of organic *** the details remain elusive in many systems,this charge transfer has been inferred in a number of photoemission *** present electronic transport measurements in very short channel(L<100 nm)transistors made from poly(3-hexylthiophene)(P3HT).As channel length is reduced,the evolution of the contact resistance and the zero gate voltage conductance are consistent with such charge *** channel conduction in devices with Pt contacts is greatly enhanced compared to analogous devices with Au contacts,consistent with charge transfer *** current scanning tunneling microscopy(ACSTM)provides further evidence that holes are transferred from Pt into P3HT,while much less charge transfer takes place at the Au/P3HT interface.

关键词： Organic semiconductors band alignment charge transfer organic field-effect transistor scanning tunneling microscopy

Atlas of procedures in gynecologic oncology

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