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Effects of phosphodiesterase 5 inhibitors on sperm parameters and fertilizing capacity

Asian Journal of Andrology 2008年第1期10卷 115-133页

作者： F. Dimitriadis D. Giannakis N. Pardalidis K. Zikopoulos E. Paraskevaidis N. Giotitsas V. Kalaboki P.Tsounapi D. Baltogiannis Georgiou m.saito T.Watanabe I. miyagawa N.Sofildtis Laboratory of molecular Urology and Genetics of Human Reproduction Department of Urology Ioannina University School of Medicine Ioannina 45110 Greece Department of Urology Tottori University School of medicine Yonago 683 Japan

The aim of this review study is to elucidate the effects that phosphodiesterase 5 （PDE5） inhibitors exert on spermatozoa motility, capacitation process and on their ability to fertilize the oocyte. Second messenger systems such as the cAmP/adenylate cyclase （AC） system and the cGmP/guanylate cyclase （GC） system appear to regulate sperm functions. Increased levels of intracytosolic cAmP result in an enhancement of sperm motility and viability. The stimulation of GC by low doses of nitric oxide （NO） leads to an improvement or maintenance of sperm motility, whereas higher concentrations have an adverse effect on sperm parameters. Several in vivo and in vitro studies have been carried out in order to examine whether PDE5 inhibitors affect positively or negatively sperm parameters and sperm fertilizing capacity. The results of these studies are controversial. Some of these studies demonstrate no significant effects of PDE5 inhibitors on the motility, viability, and morphology of spermatozoa collected from men that have been treated with PDE5 inhibitors. On the other hand, several studies demonstrate a positive effect of PDE5 inhibitors on sperm motility both in vivo and in vitro. In vitro studies of sildenafil citrate demonstrate a stimulatory effect on sperm motility with an increase in intracellular cAmP suggesting an inhibitory action of sildenafil citrate on a PDE isoform other than the PDE5. On the other hand, tadalafil＇s actions appear to be associated with the inhibitory effect of this compound on PDE11. In vivo studies in men treated with vardenafil in a daily basis demonstrated a significantly larger total number of spermatozoa per ejaculate, quantitative sperm motility, and qualitative sperm motility; it has been suggested that vardenafil administration enhances the secretory function of the prostate and subsequently increases the qualitative and quantitative motility of spermatozoa. The effect that PDE5 inhibitors exert on sperm parameters may lead to the impr

关键词： sperm fertilizing capacity phosphodiesterase 5 inhibitors spermatozoa testis male infertility

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m(o|¨)ssbauer Spectroscopic Study of Fe-Oxipnictide Superconductors

M(o|¨)ssbauer Spectroscopic Study of Fe-Oxipnictide Superco...

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作者： S.Kitao Y.Kobayashi m.Kurokuzu m.saito Y.Kamihara m.Hirano T.mitsui H.Hosono m.Seto Research Reactor Institute Kyoto University CREST Japan Science and Technology Agency ERA TO-SORST Japan Science and Technology Agency Tokyo Institute of Technology Japan Atomic Energy Agency ERATO-SORST Japan Science and Technology Agency

INTRODUCTION:Recently,Kamihara et *** a new series of superconductors in Fe-oxipnictides LaFePO and,successively,F-doped LaFeAsOF with the transition temperature(To) of 26 *** magnetic elements,such as Fe,had been thought to be incompatible with the emergence of superconductivity, these reports surprised many researchers and have brought extensive following ***, first-principles calculations for the Fe-oxipnictides showed that the 3d-bands of Fe are primary components

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极低温处理提高γ射线照射水稻种子的诱变效率

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原子能农业译丛 1981年第1期 18-22页

作者： H.Nakai m.saito 田禾李淑娴日本静冈大学农学系日本京都大学原子反应堆实验所

在极低温（-196℃）下,用（60）Co γ射线照射了含水量约为13％的水稻干种子。发现冷冻处理时m-植株成活率、幼苗高度和结实方面的损伤,均明显地小于未处理的对照。m2代叶绿素及抽穗期的突变频率并未因此受到影响,采用较高剂量结合冷冻... 详细信息

在极低温（-196℃）下,用（60）Co γ射线照射了含水量约为13％的水稻干种子。发现冷冻处理时m-植株成活率、幼苗高度和结实方面的损伤,均明显地小于未处理的对照。m2代叶绿素及抽穗期的突变频率并未因此受到影响,采用较高剂量结合冷冻处理,可以显著地提高突变频率。还发现,m2代不育或半不育突变体的频率,在冷冻处理中显著地低于未冷冻的对照。

关键词：突变率抽穗期诱变效率冷冻处理突变频率突变体突变型水稻种子自由基游离基结实率叶绿素射线剂量染色体畸变辐射损伤生物辐射效应极低温

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应用宽带P波波形进行实时地震警报

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世界地震译丛 2004年第1期35卷 14-17页

作者： S.Tsuboi m.saito m.Kikuchi 王志敏刘丽君管志光河南省地震局

我们研制出一种在大地震发生之前数秒钟能够对地震发生做出早期警报的系统。我们假定宽带P波波形的垂直位移是地震的远场震源时间函数。基于地震矩与震源持续时间的关系,当初始P波震相持续时间超过3 s时,我们就可以发布发生了一次震级大... 详细信息

我们研制出一种在大地震发生之前数秒钟能够对地震发生做出早期警报的系统。我们假定宽带P波波形的垂直位移是地震的远场震源时间函数。基于地震矩与震源持续时间的关系,当初始P波震相持续时间超过3 s时,我们就可以发布发生了一次震级大于6级地震的早期警报。我们已把这种算法应用于日本宽带观测台站记录到日本近期发生的大地震的宽带地震图。我们发现,真的可能在P波到达后3 s内判断震级超过6级的地震的发生。

关键词：地震横滨震源时间函数日本地质图地震图震级宽带连续时间持续时间地震警报震源矩震源参数地震矩日本气象厅地震基本参数震中距波初动警报系统波形

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POWER DOPPLER ULTRASONOGRAPHY OF CERVICAL LYmPHADENOPATHY IN HEAD AND NECK CANCER

POWER DOPPLER ULTRASONOGRAPHY OF CERVICAL LYMPHADENOPATHY IN...

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第二届中国国际暨第五届全国口腔颌面外科学术会议

作者： K.YUASA T.NAKANO W．KAGE T.KAWAZU m.saito E.NAKAYAmA K.mIWA S.KANDA S.OZEKI T.NAGATA m.SHINOHARA T.IKEBE DEPT.OF ORAL AND mAXILLOFACIAL RADIOLOGY FACULTY OF DENTISTRY KYUSHU UNIVERSITY FUKUOKA JAPAN DEPT.OF ORAL AND mAXILLOFACIAL RADIOLOGY FACULTY OF DENTISTRY KYUSHU UNIVERSITY FUKUOKA JAPAN FIRST DEPT.OF ORAL AND mAXILLOFACIAL SURGERY FACULTY OF DENTISTRY KYUSHU UNIVERSITY FUKUOKA JAPAN IDEPT.OF ORAL AND mAXILLOFACIAL RADIOLOGY FACULTY OF DENTISTRY KYUSHU UNIVERSITY FUKUOKA JAPAN IDEPT.OF ORAL AND mAXILLOFACIAL RADIOLOGY FACULTY OF DENTISTRY KYUSHU UNIVERSITY FUKUOKA JAPAN IDEPT.OF ORAL AND mAXILLOFACIAL RADIOLOGY FACULTY OF DENTISTRY KYUSHU UNIVERSITY FUKUOKA JAPAN IDEPT.OF ORAL AND mAXILLOFACIAL RADIOLOGY FACULTY OF DENTISTRY KYUSHU UNIVERSITY FUKUOKA JAPAN IDEPT.OF ORAL AND mAXILLOFACIAL RADIOLOGY FACULTY OF DENTISTRY KYUSHU UNIVERSITY FUKUOKA JAPAN FIRST DEPT.OF ORAL AND mAXILLOFACIAL SURGERY FACULTY OF DENTISTRY KYUSHU UNIVERSITY FUKUOKA JAPAN FIRST DEPT.OF ORAL AND mAXILLOFACIAL SURGERY FACULTY OF DENTISTRY KYUSHU UNIVERSITY FUKUOKA JAPAN SECOND DEPT.OF ORAL AND mAXILLOFACIAL SURGERY FACULTY OF DENTISTRY KYUSHU UNIVERSITY FUKUOKA JAPAN SECOND DEPT.OF ORAL AND mAXILLOFACIAL SURGERY FACULTY OF DENTISTRY KYUSHU UNIVERSITY FUKUOKA JAPAN

OBJECTIVE:The aims of this study were to evaluate the usefulness of power Doppler ultrasonography for diagnosing cervical lymphadenopathy and to determine the criteria for differentiating cervical lymph node metastasis from non- *** AND mETHODS:During April 1997 and April 1998,187 lymph nodes in 36 patients with head and neck cancer were retrospectively evaluated with power Doppler *** patients were pathologically

关键词： Doppler POWER DOPPLER ULTRASONOGRAPHY OF CERVICAL LYmPHADENOPATHY IN HEAD AND NECK CANCER

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Rendering Grass Blowing in the Wind with Global Illumination

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Tsinghua Science and Technology 2010年第2期15卷 133-137页

作者： N max S saito K Watanabe m Nakajima Computer Science Department University of California Department of Computer Science Tokyo Institute of Technology

We have simulated a time varying wind field using the lattice Boltzmann model, and its effect on blades of grass with a simple mass-spring model. We present a global illumination model for multiple scattering of incident sun and sky illumination within the field of grass. We model the grass as a continuous distribution of infinitesimal colored scattering flakes and solve a system of differential equations for the radiance transport. We repeat this for a collection of grass bending directions and amounts, and then interpolate the solutions when rendering animations of blowing grass.

关键词： global illumination lattice Boltzmann method plane parallel radiation transport

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Evolving roles of magnifying endoscopy and endoscopic resection for neoplasia in inflammatory bowel diseases

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World Journal of Gastrointestinal Oncology 2022年第3期14卷 646-653页

作者： Shintaro Akiyama Taku Sakamoto Joshua m Steinberg Yutaka saito Kiichiro Tsuchiya Department of Gastroenterology University of TsukubaIbaraki 305-8575Japan Endoscopy Division National Cancer Center HospitalTokyo 104-0045Japan Department of Inflammatory Bowel Disease Gastroenterology of the RockiesDenverCO 80218United States

magnifying endoscopy is a useful technique to differentiate neoplasia from non-neoplastic lesions. Data regarding the clinical utility of magnifying endoscopy for neoplasia in patients with inflammatory bowel disease(IBD) has been *** Kudo’s pit pattern types Ⅲ-Ⅴ are findings suggestive of neoplasia in non-IBD patients, these pit patterns are predictive of IBD-associated neoplasia as ***, active chronic inflammatory processes, particularly regenerative changes, can mimic neoplastic pit patterns and may affect a meticulous evaluation of pit pattern diagnosis in patients with IBD. The clinical evidence regarding the utility of magnifying endoscopy with narrow band imaging or endocytoscopy has also been evolving in regard to the diagnosis of IBD-associated neoplasia. These advanced endoscopic techniques are promising for multiple reasons;not only for making an accurate diagnosis of neoplasia, but also in determining if endoscopic resection is appropriate for such lesions in patients with IBD. In this review, we discuss the diagnostic accuracy and limitations of magnifying endoscopy in assessing IBD-associated neoplasia and examine the feasibility and outcomes of endoscopic resection for these lesions.

关键词： magnifying endoscopy Neoplasia Ulcerative colitis Inflammatory bowel disease Endoscopic resection

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Effects of aggregating forests, establishing forest road networks, and mechanization on operational efficiency and costs in a mountainous region in Japan

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Journal of Forestry Research 2013年第4期24卷 747-754页

作者： Kazuhiro Aruga Gyo Hiyamizu Chikara Nakahata masashi saito Department of Forest Science Faculty of AgricultureUtsunomiya University Frontier Agriscience and Technology Center Faculty of AgricultureShinshu University

We investigated forest road networks and forestry operations before and after mechanization on aggregated forestry operation sites. We developed equations to estimate densities of road networks with average slope angles, operational efficiency of bunching operations with road network density, and average forwarding distances with operation site areas. Subsequently, we analyzed the effects of aggregating forests, establishing forest road networks, and mechanization on operational efficiency and costs. Six ha proved to be an appropriate operation site area with minimum operation expenses. The operation site areas of the forest owners＇ cooperative in this region aggregated approximately 6 ha and the cooperative conducted forestry operations on aggregated sites. Therefore, 6 ha would be an appropriate operation site area in this region. Regarding road network density, higher-density road networks increased operational expenses due to the higher direct operational expenses of strip road establishment. Therefore, road network density should be reduced to approximately 200 m.

关键词： aggregating forests establishing forest road networks mechanization operational efficiency costs

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mesomorphic behavior of new azomethine liquid crystals having terminal iodo group

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Chinese Chemical Letters 2011年第3期22卷 260-263页

作者： Sie-Tiong Ha Teck-Leong Lee Guan-Yeow Yeap masato m.Ito Ayumu saito masaaki Watanabe Department of Chemical Science Faculty of ScienceUniversiti Tunku Abdul RahmanJln UniversitiBandar Barat31900 KamparPerakMalaysia Liquid Crystal Research Laboratory School of Chemical SciencesUniversiti Sains Malaysia11800 MindenPenangMalaysia Faculty of Engineering Soka University1-236 Tangi-choHachiojiTokyo 192-8577Japan

A series of azomethine esters,3-hydroxy-4-{[（4-iodophenyl）imino]methyl}phenyl alkanoates possessing even number of carbon atoms at the terminal alkanoyloxy chain（C_（n-1）H_（2n-1）COO-,n = 4,6,8,10,12,14） was synthesized.n-Butanoyloxy was found non-mesogenic,whilst n-hexanoyloxy to n-tetradecanoyloxy exhibited enantiotropic smectic A phase with fan-shaped *** was found that the length of terminal alkanoyloxy chain influenced the mesomorphic properties.

关键词： Liquid crystals Azomethine ester Enantiotropic Smectic A

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Estimating harvest costs and projecting quantities of logging residues for small-scale forestry in Nasushiobara, Tochigi Prefecture, Japan

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Journal of Forestry Research 2014年第4期25卷 965-974页

作者： Chikara Nakahata Ryo Uemura masashi saito Kanae Kanetsuki Kazuhiro Aruga Department of Forest Science Faculty of Agriculture Utsunomiya University 350 Mine Utsunomiya 321-8505 Japan Frontier Agriscience and Technology Center Faculty of Agriculture Shinshu University Nagano 399-4598 Japan Nasunogahara Land Improvement Districts Tochigi 329-2807 Japan

We used GIS on a regional scale to estimate and compare supply potentials and costs of small-scale logging systems, a mini-forwarder and a 4-ton truck operated by private logging contractors, and manual logging and a light truck operated by individual forest own- ers, with the mechanized operational system of the Forest Owners＇ Asso- ciation. Total potential yields of timber and logging residues were esti- mated as 418,895 m3 and 254,962 m3, respectively. The economic bal- ances were estimated and available amounts were projected as supply potentials from profitable sub-compartments. As a result, available amounts of timber and logging residues were estimated at 375,466 m3 （89.9%） and 203,850 m3 （80.0%）, respectively. Because their transport expenses were lower than for other systems the most profitable sub-compartments were operated by private logging contractors who sold logging residues at a plant. The profitable sub-compartments operated by individual forest owners were few because the extracting distances were usually greater than 20 m. Raising logging residue prices from 3,000 yen·m-3 to 4,080 yen·m-3 or 6,800 yen·m-3, and establishing forest roads, which reduced some extracting distances to less than 20 m, increased the number and area of profitable sub＊compartments, and increased available amounts of logging residues.

关键词： GIS supply potentials private logging contractor individual

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