Distribution patterns of leptocephali in the Kuroshio–Oyashio transitional region of the western North Pacific     

MASANORI TAKAHASHI  NORITAKA MOCHIOKA  SEKIO SHINAGAWA  AKIHIKO YATSU  AKINOBU NAKAZONO 《Fisheries Oceanography》2008,17(3):165-177

Leptocephalus assemblages and distribution patterns were studied in the Kuroshio–Oyashio transitional region of the western North Pacific. A total of 479 leptocephali, representing at least 21 species (types) including eight undescribed types, were collected during a cruise of the T/V Hokuho Maru from 8 to 30 May 2002. The most abundant leptocephali were the congrids Gnathophis nystromi nystromi and Gnathophis nystromi ginanago. The assemblages at each station were clustered into four groups (one group in the Kuroshio region and three in the transition zone) using the ordination and the fuzzy c‐means method based on species composition similarities between stations. Each leptocephalus species was also clustered by the same method into one of three groups. The first group had the greatest numbers of species and mainly occurred at the station group in the Kuroshio region, sharing a similar distribution to G. n. nystromi. The second group had the greatest abundance, especially in the transition zone, but contained only one species, G. n. ginanago, which also occurred at all stations. Moreover discrimination of station groups in the transition zone corresponded well with the assemblage pattern of this species group. The last species group comprised rare and low abundance species. Most leptocephali in the study area were reported from the Kuroshio upstream region, so the discrimination of leptocephali assemblages in the study area may reflect their different ecology. Furthermore, the analytical methods used in this study yielded more meaningful and clearer groups than the other usual methods, validating application of this analysis to complex areas such as the transition zone.  相似文献   

Epidemiology of jockey falls and injuries in flat and jump races in Japan (2003–2017)     

Fumiaki MIZOBE  Yuji TAKAHASHI  Kanichi KUSANO 《Journal of Equine Science》2020,31(4):101

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Carbon stock in litter, deadwood and soil in Japan's forest sector and its comparison with carbon stock in agricultural soils   总被引：1，自引：0，他引：1  

Masamichi TAKAHASHI  Shigehiro ISHIZUKA  Shin UGAWA  Yoshimi SAKAI  Hisao SAKAI  Kenji ONO  Shoji HASHIMOTO  Yojiro MATSUURA  Kazuhito MORISADA 《Soil Science and Plant Nutrition》2010,56(1):19-30

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Effect of summer heat environment on body temperature,estrous cycles and blood antioxidant levels in Japanese Black cow     

Miki SAKATANI  Ahmed Z. BALBOULA  Kenichi YAMANAKA  Masashi TAKAHASHI 《Animal Science Journal》2012,83(5):394-402

This study investigated the effect of summer heat environment on estrous cycles and blood antioxidant levels in Japanese Black cows. A total of 13 non‐lactating Japanese Black cows (summer: 9, winter: 4) were examined. Body temperature was measured rectally and intravaginally using a thermometer and data logger, respectively. Estrous behavior was monitored using a radiotelemetric pedometer that recorded walking activity. Rectal temperatures were higher during summer than winter (P < 0.001). There was an acute increase in vaginal temperature at the onset of estrus during winter but such an increase was not observed during summer. Walking activity during estrus decreased dramatically in the summer compared to the winter. Duration of estrous cycle was longer in summer (23.4 days, P < 0.05) than winter (21.5 days), and the subsequent rise in progesterone concentrations following estrus tended to be delayed in summer. The level of thiobarbituric acid reactive substances (TBARS) in peripheral blood cells was higher during summer (P < 0.05), while the levels of superoixde dismutase (SOD), glutathione peroxidase (GPx) and glutathione were lower (P < 0.05). These results indicate that high ambient temperature during summer increases both body temperature and oxidative stress, and also reduces signs of estrus in Japanese Black cows.  相似文献   

Addition of D-penicillamine,hypotaurine, and epinephrine (PHE) mixture to IVF medium maintains motility and longevity of bovine sperm and enhances stable production of blastocysts in vitro     

Sung-Sik KANG  Keisuke KOYAMA  Weiping HUANG  Yinghua YANG  Yojiro YANAGAWA  Yoshiyuki TAKAHASHI  Masashi NAGANO 《The Journal of reproduction and development》2015,61(2):99-105

The present study aimed to establish an efficient system for bovine embryo production by in vitro fertilization (IVF) that can achieve stable normal fertilization and blastocyst developmental rates in any bull without optimization of the sperm concentration in IVF medium. We examined the effects of a PHE mixture (20 μM D-penicillamine, 10 μM hypotaurine and 1 μM epinephrine), theophylline (2.5 mM), and sperm concentration (1, 2 or 5 × 10⁶ cells/ml) on fertilization and blastocyst developmental rates. High cleavage rates (78.3 to 92.4%) and blastocyst developmental rates (31.9 to 62.0%) at day 7 were obtained in the presence of PHE and theophylline in IVF medium with a sperm concentration of 2 × 10⁶ cells/ml using sperm from 9 bulls. In addition, the synergistic effect of PHE and theophylline on normal fertilization (2 pronuclei) was clarified at 12 h after IVF with a sperm concentration of 1 × 10⁶ cells/ml. Moreover, high linearity, high flagellar beat cross frequency, and low amplitude of lateral head of motile sperm were found by computer-assisted sperm analysis. In conclusion, the combination of the PHE mixture and theophylline synergistically accelerates sperm motility and sperm penetration of bovine oocytes. Theophylline activates sperm motility with increasing intracellular cAMP. However, PHE prevents an excessive increase of cAMP and maintains sperm motility without hyperactivation. When the combination of PHE and theophylline is added to IVF medium at a sperm concentration of 2 × 10⁶ cells/ml, we can achieve stable normal fertilization and blastocyst development in any bull.  相似文献   

Lymphangiosarcoma with systemic metastases in a Japanese domestic cat     

Atigan THONGTHARB  James K. CHAMBERS  Kazuyuki UCHIDA  Ken-ichi WATANABE  Ayaka TAKAHASHI  Manabu MOCHIZUKI  Ryohei NISHIMURA  Hiroyuki NAKAYAMA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(3):371-374

A 4-year-2-month-old female Japanese domestic cat was diagnosed with lymphangiosarcoma through tissue biopsy of an amputated leg. Two months later, the cat was euthanized, and postmortem findings revealed edema, and bruising at the caudal region of the trunk, pulmonary hemorrhage, pulmonary nodules and mediastinal lymphadenopathy. Microscopically, neoplastic tissues were observed in the dermis and subcutis of the trunk, lung, mediastinal lymph nodes, diaphragm, omentum and mesentery. The tumor cells were spindle to polygonal-shaped with nuclear pleomorphism aligning along pre-existing collagen bundles and forming irregular vascular channels in which the erythrocytes were rarely observed. These cells were immunopositive for vimentin, von Willebrand factor and CD31. Based on the histopathological and immunohistochemical features, the neoplasia was diagnosed as lymphangiosarcoma with systemic metastases.  相似文献   

Development of a programmable piggyback syringe pump and four-times-a-day injection regimen for superovulation in non-lactating Holstein cows     

Abdul Razaq IRSHAD  Taihei SASAKI  Tomoaki KUBO  Naoyuki ODASHIMA  Keiji KATANO  Takeshi OSAWA  Toru TAKAHASHI  Yoshiaki IZAIKE 《The Journal of reproduction and development》2015,61(5):485-488

The objectives of the present study were to develop a programmable piggyback syringe pump for bovine superovulation and to evaluate the effects of a four-times-a-day injection regimen using the pump. Non-lactating Holstein cows were treated with a total of 30 armour units of porcine FSH by injection four times a day with the pump (study, n = 9) or injection twice a day manually (control, n = 9) for four consecutive days from D10 of the estrous cycle. The pump-driven program successfully induced superovulation in all cows tested. The numbers of small (3– < 5 mm in diameter) and large (≥ 10 mm in diameter) follicles were greater in the study group on D11-13 and D14, respectively. There were fewer unovulated follicles detected on D21 (7 days after estrus) in the study group than in the control group (1.2 ± 0.4 and 3.2 ± 0.6, respectively).  相似文献   

Persistence of CaCl₂ washing effect for amelioration of a Cd-contaminated paddy field soil     

Takeshi HAYASHI  Toshikatsu KIDA  Masami NANZYO  Tadashi TAKAHASHI  Mitsuo HONNA  Yoshio AIKAWA  Koichi YOSHIHARA 《Soil Science and Plant Nutrition》2007,53(6):720-728

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CONTOUR INTERACTION AND VISUAL RESOLUTION: CONTRALATERAL EFFECTS     

FLOM MC  HEATH GG  TAKAHASHI E 《Science (New York, N.Y.)》1963,142(3594):979-980

Detection of the gap in a four-position Landolt C presented to one eye is impaired by critically spaced surrounding bars seen only by the other eye. The intensity and spatial extent of this contralateral contour interaction match those obtained ipsilaterally. These results indicate that the neural site for this loss of visual information is supraretinal.  相似文献   

Synthesis of 5-hydroxykynurenine     

MAKINO K  TAKAHASHI H 《Science (New York, N.Y.)》1953,118(3075):699

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