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91.
92.
Masafumi AMANO Takeshi YAMANOME Hideaki YAMADA Koichi OKUZAWA Kunio YAMAMORI 《Fisheries Science》2004,70(5):812-818
ABSTRACT: A pleuronectiform fish, the barfin flounder Verasper moseri , expresses three gonadotropin-releasing hormone (GnRH) forms in the brain: salmon GnRH (sGnRH), chicken GnRH-II (cGnRH-II) and seabream GnRH (sbGnRH). To clarify the effects of photoperiod on GnRH systems, changes in brain and pituitary GnRH peptide levels were examined using time-resolved fluoroimmunoassays. In experiment 1, 5-month-old male barfin flounder (mean total length 9.0 cm, body weight 11.0 g) were divided into short (8:16 h light : dark [L:D] cycle; lights on 08.00–16.00 hours) and long photoperiod (16:8 h L:D cycle; lights on 04.00–20.00 hours) groups in mid September and maintained until November under natural water temperature (19.3–15.2°C). Brain sGnRH concentrations were significantly higher in the 16:8 h L:D group than in the 8:16 h L:D group, whereas no significant differences were observed in total length, body weight, plasma testosterone concentration, brain cGnRH-II concentration and pituitary sbGnRH content. In experiment 2, 7-month-old male barfin flounder (mean total length 16.5 cm, body weight 76.8 g) were divided into short and long photoperiod groups in mid December and maintained until February under natural water temperature (12.5–6.6°C). Total length, body weight and condition factor were significantly greater in the 16:8 h L:D group than in the 8:16 h L:D group, whereas no significant differences were observed in plasma testosterone concentration and GnRH levels in the brain and pituitary. These results indicate that levels of sGnRH in barfin flounder are influenced by photoperiodic treatment dependent on water temperature and/or body size. 相似文献
93.
T Taira T Fujinaga K Tamura M Izumi H Itoh N Tsunoda K Yamashita M Okumura S Mizuno 《American journal of veterinary research》1992,53(6):961-965
Equine alpha 1-acid glycoprotein (alpha 1AG) was isolated from equine serum by successive ammonium precipitation, anion- and cation-exchange chromatographies, and gel filtration. Purified equine alpha 1AG had a molecular weight of 46,000 +/- 1,000, and contained 31.4% carbohydrate. Gel isoelectric focusing revealed an isoelectric point range of 2.8 to 3.7. With immunoelectrophoresis, it was found that alpha 1AG migrated to the alpha 1-globulin region. Single radial immunodiffusion was used for quantitative measurement of alpha 1AG in equine serum. In clinically normal foals, serum alpha 1AG was undetectable (less than or equal to 20 micrograms/ml) in less than or equal to 7-day-old foals, but was detected by 14 days. The alpha 1AG concentration (mean +/- SD) increased to reach mean adult values of 99.23 +/- 26.90 micrograms/ml by 1 year of age. The alpha 1AG concentration in pregnant mares decreased at 2 to 3 months before parturition, then gradually increased until 1 day after parturition, when a brief decrease was observed. The concentration increased again at 2 weeks after foaling, then a decrease was observed, after which the alpha 1AG concentration increased again by 2 to 4 months after parturition. The concentration of serum alpha 1AG quickly rose to peak values 2 to 3 days after castration and jejunojejunostomy in adult horses, returning to baseline values by 14 to 28 days after surgery. The alpha 1AG was concluded to be an acute-phase reactive protein in horses. 相似文献
94.
Subyakto Toshimitsu?Hata Isamu?Ide Takeshi?Yamane Shuichi?KawaiEmail author 《Journal of Wood Science》2004,50(2):157-161
Laminated veneer lumber joints made with metal plate connectors were protected with wood carbon phenolic spheres (CPS) sheeting and tested for creep under fire. The effects of the carbonizing temperature of charcoal, used as raw material for the CPS sheets, the thickness, and the location of the sheet on the joint regarding the fire-resistance performance of the joint were studied. The time to rupture of the joints covered with CPS sheets made from charcoal carbonized at 800°C (CPS800) was slightly prolonged compared with that of uncovered joints. On the other hand, the time to rupture of CPS sheets made from charcoal carbonized at 1600°C (CPS1600) was markedly extended. The changes in the charcoal properties due to increasing the carbonizing temperature might be the main reason the CPS1600 sheets had higher fire-resistance performance. The thickness and location of CPS1600 sheets have significant effects on the fire resistance of the joint. A highly fire-resistant laminated veneer lumber joint was obtained using a CPS1600 sheet. The CPS1600 sheet with a thickness of 3mm covering three sides of the joint prolonged the time to rupture 16-fold compared with that of unprotected joints.Part of this paper was presented at the 4th International Wood Science Symposium, Serpong, Indonesia, September 2002 相似文献
95.
Akinori Takasuka Kirara Nishikawa Hiroshi Kuroda Takeshi Okunishi Yugo Shimizu Hideo Sakaji Shin‐Ichi Ito Tadashi Tokai Yoshioki Oozeki 《Fisheries Oceanography》2016,25(4):390-406
Growth variability was examined for Pacific saury Cololabis saira larvae under contrasting environments across the Kuroshio axis, based on samples collected during the winter spawning season in 2013 and 2014. The growth rate index (residual of the otolith marginal 3‐day mean increment width from the linear regression on knob length) of larvae was compared among three areas: the inshore side of the Kuroshio axis, the Kuroshio axis, and the offshore side of the Kuroshio axis in relation to sea surface temperature (SST), salinity (SSS) and chlorophyll‐a (CHL) concentration. The larvae were more densely distributed in the Kuroshio axis and offshore areas of higher temperature and salinity and lower chlorophyll‐a concentration than in the inshore areas of lower temperature and salinity and higher chlorophyll‐a concentration. No marked differences in the growth rate index were found among the three areas, even though the larvae in the inshore areas showed slightly higher growth rates in 2013. Despite the broad ranges of environmental factors, no clear relationship between the growth rate index and any environmental factor was detected. The survival potential of Pacific saury larvae was considered to be at least comparable under contrasting environments across the Kuroshio axis. Such a geographical homogeneity is concluded to be attributable to compensable effects of physical and biological factors. We hypothesize that the minority under physically‐unfavorable but biologically‐favorable conditions on the inshore side of the Kuroshio axis could survive equally well as the majority under physically‐favorable but biologically‐unfavorable conditions around the Kuroshio axis and on the offshore side of the Kuroshio axis. 相似文献
96.
Chahan B Jian Z Jilintai Miyahara K Tanabe S Xuan X Sato Y Moritomo T Nogami S Mikami T Maruyama S Inokuma H 《Veterinary parasitology》2007,144(1-2):184-187
Tick DNA samples from cattle in Xinjiang Uygur Autonomous Region Area, China, were examined for Rickettsia infection by citrate synthase gene-based PCR and sequencing. Four positive samples were detected from Haemaphysalis danieli and high levels of similarity were found with recently detected 'Candidatus Rickettsia principis.' 相似文献
97.
Masayuki Itoh Takashi Matsubara Satomi Shiodera Kotaro Iizuka Ken Sakurai Yoko Nakajima Hiroki Ohashi Ivan Manalu 《Land Degradation u0026amp; Development》2020,31(10):1217-1224
In many parts of Southeast Asia, opencast hydraulic tin mining has been carried out since the colonial era. Regardless of its scale, this mining method has significantly affected microtopography and left extremely degraded soil surfaces, where vegetation can hardly grow. Therefore, the identification of a feasible method for the rehabilitation and reforesting of these areas is a long‐term issue. In this study, we aimed to clarify the subsurface geological (soil properties and distribution) and hydrological conditions at a post‐tin mining site on an Indonesian island using an electrical resistivity survey combined with microtopographic information. The electrical resistivity survey of the study site provided information about the distribution of bedrock and sandy and clayey soils, reflecting mining activities. Furthermore, direct and continuous groundwater level monitoring showed the ranges of groundwater fluctuation depending on the soil and climate conditions. Our study demonstrates that subsurface assessment by electrical resistivity survey can provide essential information, contributing to the development of feasible plans for reforestation or transformation to agricultural land at post‐tin mining sites through the improvement of physical conditions and soil fertility. 相似文献
98.
Hisako KYAN Taketoshi TAKARA Katsuya TAIRA Takeshi OBI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(8):1303
Cats are an important host of Toxoplasma gondii from an epidemiological perspective because they are the only definitive hosts that excrete oocysts in their feces. In this study, 201 free-ranging cats in Okinawa were examined for T. gondii infection. Using the latex agglutination test, we detected antibodies against T. gondii in 26.9% (54/201) of the cats. Oocysts of T. gondii were not detected upon microscopic examination of the feces of 128 cats. T. gondii was isolated from the tissues of 9 out of 24 seropositive or pseudo-seropositive cats with a bioassay using laboratory mice. Genotyping for the GRA6 gene revealed that five and four of the isolates were type I and II, respectively. 相似文献
99.
Hiroyuki Imai;Naoki Iwamori;Tokuko Iwamori;Sumito Matsuya;Kiyoshi Kano;Ken Takeshi Kusakabe; 《Anatomia, histologia, embryologia》2024,53(1):e12976
Mouse embryos in the early-implantation stage require manipulation under a microscope. While the extraction of DNA, RNA and proteins from a single sample allows for both determination of genetic type and analysis of gene expression, whole mount analysis is not possible. In this study, we explored the applicability of PCR using extraembryonic tissues, especially the decidual side tissue after isolating the embryos from implantation sites to establish a method for determining the genetic type of embryos. The implantation site was resected at each day from the date of vaginal plug confirmation, separated into embryos and deciduae. Genomic DNA were isolated separately from the embryos and the deciduae. PCR was performed using these genomic DNA, and the band patterns were compared after electrophoresis. As a result, we demonstrated that detecting embryo-derived cells in the decidua allows determination of the sex and presence of transgenes without harming the mouse embryos themselves, from 8.5 days of age. This method enables the determination of the genetic type of mouse embryos without damaging. This technique would expand the adaptations for analysis of mouse implanted embryos. 相似文献
100.
Masaya Tanaka;Junya Yase;Takeshi Kanto;Masahiro Osakabe; 《Pest management science》2024,80(2):698-707
Tetranychus urticae is a hard-to-control pest of greenhouse strawberry production. Nighttime ultraviolet B (UV-B) radiation using light reflection sheets (LRS) has been applied as a physical method to control T. urticae through direct ovicidal effects (the UV method). However, because strawberry leaves grow more densely, UV-B radiation fails to reach the lower leaf surfaces inhabited by spider mites; therefore, a complementary method is required. We propose the supplemental application of phytoseiid mites in greenhouse strawberry production. We evaluated the control effects of UV-B irradiation, phytoseiid mite application and their combined use. The effects of UV-B irradiation on the degree of overlap relative to the independent distributions (ω) between predators and prey were also analyzed. 相似文献