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Study clarifies associations between hypogonadism and health in aging men

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Asian Journal of Andrology 2012年第6期14卷 809-810页

作者： john amory Department of Medicine University of Washington Seattle WA 98195 USA

Tajar and colleagues present the associations between moderate and severe hypogonadism, symptoms of androgen deficiency and the prevelence of end-organ evidence of androgen deficency in 2966 older men in the European ...

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Isotretinoin for the treatment of nonobstructive azoospermia: a pilot study

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Asian Journal of Andrology 2021年第5期23卷 537-540页

作者： john k.amory Charles H Muller Thomas J Walsh Department of Medicine University of WashingtonSeattleWA 98195USA Department of Urology University of WashingtonSeattleWA 98195USA

The treatment of men with infertility from azoospermia is *** some men with severe oligozoospermia improve sperm output during treatment with isotretinoin,we treated nine men with azoospermia with isotretinoin to determine if azoospermic men would also respond to isotretinoin *** of these men who had a previous negative testicular sperm extraction(TESE)was found to have an area of sperm production on a postisotretinoin testicular *** man achieved a pregnancy and a live birth of a healthy,term daughter after in vitro fertilization coupled with intracytoplasmic sperm injection(IVF/ICSI).A second subject had a positive TESE after treatment as *** study of isotretinoin therapy in men with azoospermia undergoing testicular sperm harvesting procedures is warranted.

关键词： treatment injection pregnancy

Androgens exert sexually dimorphic effects on angiogenesis： novel insight into the relationship between androgens and cardiovascular disease

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Asian Journal of Andrology 2011年第4期13卷 626-627页

作者： k.tya B Rubinow john k.amory Stephanie T Page Division of Metabolism Endocrinology and Nutrition University of Washington Seattle WA 98195 USA General internal Med c ne Un versity of Washington Seattle WA 98195 USA

The effects of androgen exposure on cardiovascular disease （CVD） risk.in men remain poorly understood. Given the earlier incidence of CVD among men relative to women, androgens historically have been assumed to pote... 详细信息

关键词： Androgens sexually

Precipitation variation in the northeastern Tibetan Plateau recorded by the tree rings since 850 AD and its relevance to the Northern Hemisphere temperature

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Science China Earth Sciences 2006年第4期49卷 408-420页

作者： john k. k.tzbach Center for Climatic Research University of Wisconsin-Madison Madison 53706 USA

Three well-dated Sabina Przewalsk.i ring-width chronologies from Dulan, China, have been used to reconstruct annual precipitation (from prior July to current June) variations on the northeast Tibetan Plateau since 850 AD. The reconstructions account of the instrumentally recorded precipitation variance are: 54.7% for the period of 1385-2000AD; 50.5% for 1099-1384AD and 45.7% for 850-1098AD. On the millenary scale, the precipitation variation over this region displays “W” shape, which has three peak. and two valleys. The precipitation is low during 1571-1879 AD, and high during 1880-2000 AD. 1900-2000 AD is the century with the highest precipitation over the northeast Tibetan Plateau in the last 1000 years, and 1962-2000 is the period with the highest pre- cipitation, and the highest variability of precipitation as well in the last 1000 years. The reconstructed series also reveals that the variability of annual precipitation is large when the precipitation is more, and contrarily, variability is small when the precipitation is low. With the temperature increasing obvi- ously in the 20th century, the precipitation in the study region significantly increased too, the variability of precipitation became larger, and drought and flooding occurred more frequently. The yearly tree-ring width (high frequency signal) series in this region reflects the local annually precipitation variation. However, the series with 40-year moving average (low frequency signal) cor- responds to the Northern Hemisphere temperature variations on the decadal to centurial scale. It correlates significantly with seven temperature curves of the Northern Hemisphere in the different time spans. For example, the correlation coefficients with the most temperature curves are around 0.9 during the period of 1852-1982 AD. In general, the temperature and the precipitation change syn- chronously in the Dulan region. It means that low temperature corresponds to low precipitation, andvice versa. This relations

关键词： Dulan China, Sabina Przewalsk.i, annual precipitation, the Northern Hemisphere temperature.

Hydrogenic Donor in a Spherical Quantum Dot with Different Confinements

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Chinese Physics Letters 2009年第8期26卷 309-312页

作者： A. john Peter k. Navaneethak.ishnan Govt. Arts College Melur-625 106 Madurad India Madurai k.maraj-University Madurai-625 021 India

Binding energies of a hydrogenic donor in a spherical GaAs quantum dot surrounded by Ga1-xA4xAs matrix are calculated. The results are presented for realistie barrier heights corresponding to different values of x （x 〈 0.4）. The calculations are performed under two different conditions：（i） a spherical dot with square well confinement and （ii） a dot with parabolic potential well confinement. The results show that （i） the donor ionization energies are always higher under parabolic confinement as compared to a dot of the same radius under square well confinement and （ii） the oscillator strengths coupling ground state with excited states are two orders larger under parabolic confinement. Our results are in agreement with the results of other researchers.

关键词： ELECTRON donor-acceptor complexes QUANTUM dots BINDING energy OSCILLATOR strengths PLASMA confinement QUANTUM wells GALLIUM arsenide semiconductors

Phyllofenone A, a New Scalarane Sesterterpene from the Sponge Phyllospongia Foliascens(Pallas)

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Chemical Research in Chinese Universities 1991年第2期7卷 100-106页

作者： john k. Snyder Department of Chemistry Boston University Boston USAhe present paper covers the structure of a new sesterterpene phyllofenone A(1) isolated from the South China Sea sponge Phyllospongia foliascens. Phyllofenone A is a member of the scalarane class of sesterterpenes with a (C-20 C-24)-bishomo-(C-25)-nortetra-cyclic skeleton. The structure charcterization was based on one- and two-dimensional NMR and mass spectroscopy with the assistance of molecular modeling. Phyllofenone A shows weak antifungal activity against Candida pseudotropicalis.

The present paper covers the structure of a new sesterterpene, phyllofenone A(1) , isolated from the South China Sea sponge Phyllospongia foliascens. Phyllofenone A is a member of the scalarane class of sesterterpenes with a (C-20, C-24)-bishomo-(C-25)-nortetra-cyclic sk.leton. The structure charcterization was based on one- and two-dimensional NMR and mass spectroscopy with the assistance of molecular modeling. Phyllofenone A shows weak.antifungal activity against Candida pseudotropicalis.

关键词： Sponge Sesterterpene Selective INEPT 2D NMR

Analyzing biases of nitrogen contents and δ^(15)N values arising from acidified marine sediments with different CaCO_3 concentrations

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Acta Oceanologica Sinica 2018年第8期37卷 1-5页

作者： PENG Yajun LIU Dongyan WANG Yujue RICHARD Pierre k.ESING john k. k.y Laboratory of Coastal Zone Environmental Processes and Ecological Remediation Yantai Institute of Coastal Zone Research Chinese Academy of Sciences School of Management Science Guizhou University of Finance and Economics State k.y Laboratory of Estuarine and Coastal Research East China Normal University Littoral Environment et Sociétés UMR 7266 CNRS-Université de La Rochelle CSIRO Oceans and Atmosphere and University of Western Australia Oceans Institute Indian Ocean Marine Research Centre

In some studies, the researchers pretreated and measured organic carbon, nitrogen and their isotopes（δ^（13）C and δ^（15）N） of marine sediment together, to save costs and resources of analysis. However, the procedure of acidification to remove inorganic carbon for analysing δ^（13）C can affect the values of nitrogen and δ^（15）N, and the biases vary a lot depending on the CaCO_3 contents of sediments. In this study, the biases of total nitrogen（TN）and δ^（15）N values arising from acidified sediments were compared between the CaCO_3-poor（1%–16%） and CaCO_3-rich（20%–40%） samples. TN and δ^（15）N values were altered during acid treatment（without centrifugation） that possibly led to N-containing compounds volatilization. For CaCO_3-poor samples, acidification led to a range of 0%–40% TN losses and 0‰–2‰ shift in δ^（15）N values; and 10%–60% TN losses and 1‰–14‰ shift in δ^（15）N values for CaCO_3-rich samples. The biases from most samples exceeded the precision of the instrument（0.002% for TN and 0.08‰ for δ^（15）N）, and high biases could mislead our judgment for the environmental implication of the data. Thus,avoiding co-analysis of organic carbon, nitrogen and their isotopes（δ^（13）C and δ^（15）N） in sediments, even for CaCO_3-poor marine sediments, is necessary.

关键词： stable isotope nitrogen nitrogen CaCO3 acidification marine sediment

Testicular fine-needle aspiration for the assessmen＇ of intratesticular hormone concentrations

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Asian Journal of Andrology 2016年第1期18卷 21-24页

作者： Ada P Lee Mara Y Roth Jean-Jacques Nya-Ngatchou k.t Lin Thomas J Walsh Stephanie T Page Alvin M Matsumoto William J Bremner john k.amory Bradley D Anawalt Department of Medicine University of California San Francisco San Francisco CA USA Department of Medicine and Center for Research in Reproduction and Contraception University of Washington Seattle WA USA Department of Obstetrics and Gynecology University of Washington Seattle WA USA Department of Urology University of Washington Seattle WA USA Department of Medicine Geriatric Research Education and Clinical Center VA Puget Sound Health Care System Seattle WA USA.

Measurement of intratesticular sex steroid concentrations in men informs both the development of male hormonal contraceptives and the understanding of male infertility. Given the challenges of using invasive techniques to measure testicular hormone physiology, our group has used a minimally-invasive fine-needle aspiration technique to measure intratesticular hormones in normal healthy men. Herein, we present a post-hoc analysis of the safety and efficacy of testicular fine-needle aspiration （FNA） completed as part of six clinical trials. From 2001 through 2011, a total of 404 procedures were conducted among 163 research volunteers, 85.9% of which were successful in obtaining sufficient fluid for the measurement of intratesticular steroid concentrations. Pain was the most common side effect, with 36.8% of procedures associated with moderate procedural pain and 4.7% with severe procedural pain. Postprocedural pain was uncommon and abated within a few days. Mild local bruising occurred with 14.9% of procedures. Two serious adverse events （0.5%） required surgical intervention. The risk.of an adverse event was not associated with age, body mass index, testicular size, or the volume of fluid aspirated. Testicular FNA to obtain fluid for measurement of intratesticular steroid concentrations frequently causes mild to moderate procedural pain, but serious adverse events occur rarely. Testicular FNA has been instrumental for defining human intratesticular hormone physiology and is a minimally-invasive, safe, effective method for obtaining fluid for research on testicular physiology and pathology.

关键词： male contraception physiology reproductive and urinary testis

Integrative behavioral ecotoxicology： bringing together fields to establish new insight to behavioral ecology, toxicology, and conservation

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Current Zoology 2017年第2期63卷 185-194页

作者： Elizabeth k. PETERSON David B. BUCHWALTER Jacob L. k.RBY Matthew k. LEFAUVE Claire W. VARIAN-RAMOS john R SWADDLE Department of Biological Sciences State University of New York-Albany Albany NY 12222 USA Department of Biological Sciences North Carolina State University Raleigh NC 27695 USA Department of Biology University of South Dakota Vermillion SD 57069 USA Department of Biological Sciences George Washington University Washington DC 20052 USA Department of Biology Colorado State University-Pueblo Pueblo CO 81001 USA Biology Department Institute for Integrative Bird Behavior Studies College of William & Mary Williamsburg VA 23187-8795 USA

The fields of behavioral ecology, conservation science, and environmental toxicology individually aim to protect and manage the conservation of wildlife in response to anthropogenic stressors, including widespread anthropogenic pollution. Although great emphasis in the field of toxicology has been placed on understanding how single pollutants affect survival, a comprehensive, interdis- ciplinary approach that includes behavioral ecology is essential to address how anthropogenic compounds are a risk.for the survival of species and populations in an increasingly polluted world. We provide an integrative framework.for behavioral ecotoxicology using Tinbergen＇s four postu- lates （causation and mechanism, development and ontogeny, function and fitness, and evolution- ary history and phylogenetic patterns）. The aims of this review are： 1） to promote an integrative view and re-define the field of integrative behavioral ecotoxicology; 2） to demonstrate how study- ing ecotoxicology can promote behavior research; and 3） to identify areas of behavioral ecotoxicol- ogy that require further attention to promote the integration and growth of the field.

关键词： animal behavior behavioral ecology conservation phylogenetic pollution toxicology.