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Can DNA fragmentation of neat or swim-up spermatozoa be used to predict pregnancy following ICSI of fertile oocyte donors？

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Asian Journal of Andrology 2013年第6期15卷 812-818,I0010页

作者： Jaime Gosálvez Pedro Caballero carmen López-Fernández Leonor Ortega José Andrés Guijarro José Luís FernAndez Stephen D johnston Rocio Nufiez-Calonge Faculty of Biology Autonomous University of Madrid Cantoblanco Madrid 28049 Spain CIfnica Tambre Madrid 28002 Spain GINIBIC-Complejo Hospitalario Universitario A CoruRa A Corufna15006 Spain School of Agriculture and Food Science The University of Queensland Gatton 4343 Australia

This study compared the potential of assessing sperm DNA fragmentation （SDF） from neat semen and the subsequent swim-up （SU） procedure to predict pregnancy when conducting ICSI of fertile donor oocytes. Infertile females （n=81） were transferred embryos resulting from intracytoplasmic sperm injection （ICSI） of their partner＇s spermatozoa and proven donor oocytes. This model normalized the impact of female factor in putative sperm DNA repair. Semen was blindly assessed for SDF using Halosperm immediately following ejaculation （NS） and after swim-up at the time of ICSI fertilisation. There was a decrease in SDF values of the ejaculated semen sample following the swim-up protocol （P=0.000）. Interestingly, pregnancy could be equally predicted from SDF values derived from either neat or swim-up semen samples. Receiver operator curves and the derived Youden＇s indices determined SDF cutoff values for NS and SU of 24.8% and 17.5%, respectively. Prediction of pregnancy from NS SDF had a sensitivity of 75% and a specificity of 69%, whereas for SU SDF was 78% and 73%, respectively. While increased levels of SDF negatively impact reproductive outcome, we have shown that a reduction in SDF following sperm selection using ICSI with proven donor oocytes is not mandatory for achieving pregnancy. This suggests that a certain level of DNA damage that is not detectable using current technologies could be impacting on the relative success of assisted reproductive technology （ART） procedures. Consequently, we propose a modification of the so called ＇iceberg model＇ as a possible rationale for understanding the role of SDF in reproductive outcome.

关键词： assisted reproductive technology egg donation male factor sperm DNA fragmentation

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开发地球物理学的最新进展

地球物理学进展 1990年第2期5卷 22-29页

作者： DavidH.johnston 石洁

当今在石油价格下跌、国内储量减小的情况下,很多公司把注意力都集中在通过精确确定壮年油区、并更详细地描述其特征来提高储量的问题上.经济地质局的分析表明,除了阿拉斯加以外,通过加密钻探、扩展钻探和二次完孔,可使美国大陆的油储... 详细信息

当今在石油价格下跌、国内储量减小的情况下,很多公司把注意力都集中在通过精确确定壮年油区、并更详细地描述其特征来提高储量的问题上.经济地质局的分析表明,除了阿拉斯加以外,通过加密钻探、扩展钻探和二次完孔,可使美国大陆的油储量增加800亿桶,汽储量增加180万亿立方英尺.然而这只能在以详细的地质估评为基础时才能实现.

关键词：三维地震数据储层性质精确确定立方英尺地震测量孔隙度不整合面石油价格三维地震勘探岩心分析

Gas Tungsten Arc/Tungsten Inert Gas Welding of Laminations

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Gas Tungsten Arc/Tungsten Inert Gas Welding of Laminations

Development of Instrumentation for the Measurement of the Performance of Acoustic Absorbers

第十届中国钢铁年会暨第六届宝钢学术年会

作者： Gwynne johnston Erik Hilinski Tempel Steel Company

Process conditions and equipment required for GTAW/TIG welding are described in terms of fundamental theory. This covers the basics of the electrode, shielding gas, the effects of gaps and clamping pressure, and combines this theory with practical experience. Quantitative data is presented to describe the effects of weld current, weld speed, electrode diameter, electrode stand-off distance, and different grades of materials on the width and the depth of welds on laminations using electrical steel.

关键词： GTAW TIG welding steel laminations

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Open Journal of Acoustics 2015年第4期5卷 172-192页

作者： James Christopher johnston Maria A. Kuczmarski Garth Olszko NASA Glenn Research Center Cleveland OH USA Cleveland State University Cleveland OH USA

In both fixed and rotary wing aircraft, the move toward lighter structures has resulted in an increase in structural vibration and interior noise. Porous materials have been proposed as acoustic absorbers to reduce this noise. This paper discusses the development of equipment at the NASA Glenn Research Center for characterizing the acoustic performance of porous materials: a flow resistance apparatus to measure the pressure drop across a specimen of porous material, and a standing wave tube that uses a pair of stationary microphones to measure the normal incidence acoustic impedance of a porous material specimen. Specific attention is paid to making this equipment as flexible as possible in terms of specimen sizes need for testing to accommodate the small or irregular sizes often produced during the development phase of a new material. In addition, due to the unknown performance of newly developed material, safety features are included on the flow resistance apparatus to contain test specimens that shed particles or catastrophically fail during testing. Results of measurements on aircraft fiberglass are presented to verify the correct performance of the equipment.

关键词： Acoustic Impedance Acoustic Measurement Acoustic Attenuation

Clopidogrel with aspirin in High- risk patients with Acute Non- disabling Cerebrovascular Events II (CHANCE-2): rationale and design of a multicentre randomised trial

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Stroke & Vascular Neurology 2021年第2期6卷 280-285页

作者： Yongjun Wang Claiborne johnston Philip M Bath Xia Meng Jing Jing Xuewei Xie Anxin Wang Yuesong Pan Anding Xu Qiang Dong Yilong Wang Xingquan Zhao Zixiao Li Hao Li Department of Neurology Beijing Tiantan HospitalCapital Medical UniversityBeijingChina China National Clinical Research Center for Neurological Diseases BeijingChina The University of Texas at Austin Dell Medical School AustinTexasUSA Stroke Trials Unit Division of Clinical NeuroscienceUniversity of NottinghamNottinghamUK Department of Neurology The First Affiliated HospitalJinan University GuangzhouGuangzhouGuangdongChina Department of Neurology Huashan HospitalState Key Laboratory of Medical NeurobiologyFudan UniversityShanghaiChina

Background In patients with a minor ischaemic stroke or transient ischaemic attack(TIA),separate trials have shown that dual antiplatelet therapy with clopidogrel plus aspirin(clopidogrel-aspirin)or ticagrelor plus aspirin(ticagrelor-aspirin)are more effective than aspirin alone in stroke secondary ***,these two sets of combination have not been directly *** clopidogrel was less effective in stroke patients who were CYP2C19 loss-of function(LOF)allele carriers,whether ticagrelor-aspirin is clinically superior to clopidogrel-aspirin in this subgroup of patients with stroke is *** To describe the rationale and design considerations of the Clopidogrel in High-risk patients with Acute Non-disabling Cerebrovascular Events(CHANCE-2)*** CHANCE-2 is a randomised,double-blind,double-dummy,placebo-controlled,multicentre trial that compares two dual antiplatelet strategies for minor stroke or TIA patients who are CYP2C19 LOF allele carriers:ticagrelor(180 mg loading dose on day 1 followed by 90 mg twice daily on days 2-90)or clopidogrel(300 mg loading dose on day 1 followed by 75 mg daily on days 2-90),plus open-label aspirin with a dose of 75-300 mg on day 1 followed by 75 mg daily on day *** will be followed for 1 *** outcomes The primary efficacy outcome is any stroke(ischaemic or haemorrhagic)within 3 months and the primary safety outcome is any severe or moderate bleeding event within 3 *** The CHANCE-2 trial will evaluate whether ticagrelor-aspirin is superior to clopidogrel-aspirin for minor stroke or TIA patients who are CYP2C19 LOF allele carriers.

关键词： CYP2C19 aspirin patients

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对选择性迷走神经切除术的新看法

国外医学（外科学分册） 1989年第3期16卷 143-145页

作者： johnston D 张延龄

自八十年代迷走神经切除术成为十二指肠溃疡的主要手术治疗以来,仍有不少问题有待解决,诸如迷走神经干切除(TV)、选择性迷走神经切除(SV)以及高选择性迷走神经切除(HSV)的适应证,加倣胃窦切除术或引流术的指征,幽门应否保持完整,术中或... 详细信息

自八十年代迷走神经切除术成为十二指肠溃疡的主要手术治疗以来,仍有不少问题有待解决,诸如迷走神经干切除(TV)、选择性迷走神经切除(SV)以及高选择性迷走神经切除(HSV)的适应证,加倣胃窦切除术或引流术的指征,幽门应否保持完整,术中或术后各种测定神经切除完整性等试验的价值,胃壁浆肌层切开术能否替代胃壁外的迷走神经切除术等等,作者对此进行了复习和讨论。

关键词：迷走神经切除选择性改良溃疡