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71.
72.
Yamamoto Y Yamamoto T Yuto N Hildebrandt TB Lueders I Wibbelt G Shiina O Mouri Y Sugimura K Sakamoto S Kaewmanee S Nagaoka K Watanabe G Taya K 《The Journal of reproduction and development》2012,58(1):105-111
The objective of the present study was to define the secretion of prolactin (PRL) in pregnant African and Asian elephants. Levels of immunoreactive (ir-) PRL in serum and placental homogenates were measured by a heterologous radioimmunoassay (RIA) based on an ovine and human RIA system, and the localization of ir-PRL in the placenta was detected by immunohistochemistry using anti-human PRL. Circulating ir-PRL clearly showed a biphasic pattern during pregnancy in African and Asian elephants. Serum levels of ir-PRL started to increase from the 4 - 6th month of gestation and reached the first peak level around the 11-14th month. A second peak of circulating ir-PRL levels was observed around the 18-20th month of gestation followed by an abrupt decline after parturition. In contrast, in a case of abortion of an African elephant, the second peak of ir-PRL was not observed, and the levels remained low for about four months until parturition. The weight of the fetus delivered at the 17th month of gestation was 23.5 kg, which was quite small compared with normal fetuses in previous reports. Ir-PRL was detected in placental homogenates, and immunolocalization was observed in trophoblasts in both the African and Asian elephants, indicating that the placenta is the source of ir-PRL during pregnancy in elephants. The present results clearly demonstrated that circulating ir-PRL shows a biphasic pattern during normal pregnancy and that the placenta appears to be an important source of circulating ir-PRL during pregnancy in both African and Asian elephants. 相似文献
73.
Conclusions When the hydroxyl values of materials containing phenolic 3 or sterically hindered hydroxyl groups were determined by the esterification method, the values were considerably smaller than the theoretical values. In contrast, the NCO method provided hydroxyl values much closer to the theoretical values for such materials, though the values varied depending on the kinds and amounts of catalysts.The quantity of hydroxyl groups reacting with the NCO group could be directly determined by the NCO method using a catalyst mixture consisting of DABCO and DBTDL in a molar ratio of 21. Therefore, this method can be considered useful for determining the hydroxyl value before preparing polyurethane from liquefied wood or bark.Part of this paper was presented at the 51st Annual Meeting of the Japan Wood Research Society, Tokyo, April 1988 相似文献
74.
Tanaka J Horiike Y Matsuzaki M Miyazaki T Ellis-Davies GC Kasai H 《Science (New York, N.Y.)》2008,319(5870):1683-1687
Long-term potentiation (LTP) at glutamatergic synapses is considered to underlie learning and memory and is associated with the enlargement of dendritic spines. Because the consolidation of memory and LTP require protein synthesis, it is important to clarify how protein synthesis affects spine enlargement. In rat brain slices, the repetitive pairing of postsynaptic spikes and two-photon uncaging of glutamate at single spines (a spike-timing protocol) produced both immediate and gradual phases of spine enlargement in CA1 pyramidal neurons. The gradual enlargement was strongly dependent on protein synthesis and brain-derived neurotrophic factor (BDNF) action, often associated with spine twitching, and was induced specifically at the spines that were immediately enlarged by the synaptic stimulation. Thus, this spike-timing protocol is an efficient trigger for BDNF secretion and induces protein synthesis-dependent long-term enlargement at the level of single spines. 相似文献
75.
Murakami Hiroaki Yoon Seokjin Kasai Akihide Minamoto Toshifumi Yamamoto Satoshi Sakata Masayuki K. Horiuchi Tomoya Sawada Hideki Kondoh Michio Yamashita Yoh Masuda Reiji 《Fisheries Science》2019,85(6):1109-1109
Fisheries Science - In the original publication the text in right column of page 330, the sequences of primers were incorrectly published as. 相似文献
76.
77.
Masanori KOBAYASHI Chie TSUZUKI Marika KOBAYASHI Hinano TSUCHIYA Yume YAMASHITA Kanako UENO Moe ONOZAWA Masato KOBAYASHI Eiichi KAWAKAMI Tatsuya HORI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(7):1044
Oxidative stress owing to an imbalance between reactive oxygen species and antioxidants, such as coenzyme Q10 (CoQ10), is a major contributor to male infertility. We investigated the effects of the reduced form of CoQ10 (ubiquinol) supplementation on semen quality in dogs with poor semen quality. Three dogs received 100 mg of ubiquinol orally once daily for 12 weeks. Semen quality, serum testosterone, and seminal plasma superoxide dismutase (SOD) activity were examined at 2-week intervals from 2 weeks before ubiquinol supplementation to 4 weeks after the treatment. Ubiquinol improved sperm motility, reduced morphologically abnormal sperm, and increased seminal plasma SOD activity; however, it had no effect on testosterone level, semen volume, and sperm number. Ubiquinol supplementation could be used as a non-endocrine therapy for infertile dogs. 相似文献
78.
Hori T Kaseki H Fukuhara Y Oba H Mizutani T Kawakami E Tsutsui T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2006,68(10):1125-1128
The addition of Orvus ES paste (OEP) to extender may be essential for preparing frozen dog semen. The major ingredient of OEP is sodium lauryl sulfate (SLS). In this study, we compared the effect of SLS on frozen dog semen with that of OEP. There were no significant differences between the 2-mg/ml SLS group and OEP group concerning sperm motility, viability and the percentage of viable sperm with intact acrosomes after freeze-thawing. These results suggest that the effectiveness of frozen dog semen extender containing 2 mg/ml of SLS is similar effective to that demonstrated for OEP. 相似文献
79.
Hori T Odaka S Oba H Mizutani T Kawakami E Tsutsui T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2006,68(10):1055-1061
The freezing conditions for preparation of frozen canine semen by the plunging method were investigated with regard to the period of sensitization in liquid nitrogen (LN2) vapor and the height from LN2, and the semen qualities after thawing were compared with those of canine semen prepared by the simple freezer method previously reported by us. In the plunging method, 9 semen straws were prepared under the same conditions, horizontally kept at 5, 7, and 10 cm above the LN2 surface in a styrene foam box for 5, 10, and 15 min, and then plunged into LN2. The semen qualities immediately after thawing were high in the 7 cm/10 min (cooling rate: -4 to -22 degrees C/min) and 10 cm/15 min groups (cooling rate: -6 to -10 degrees C/min). On comparison of frozen semen prepared by the plunging method (7 cm/10 min) with frozen semen prepared by the simple freezer method, sperm motility and viability were significantly higher for the frozen semen prepared by the plunging method. The cooling rate in freezing was higher for the simple freezer method (cooling rate: -6 to -50.9 degrees C/min) than the plunging method. Based on these findings, horizontal placement of canine semen straws above LN2 to reduce the temperature at a slow cooling rate of about -10 degrees C/min, followed by plunging into LN2 after sensitization for 10-15 min, provides good semen qualities after thawing. 相似文献
80.
Takuya Morikawa Tatsuya Ashitani Nobuhiro Sekine Norihisa Kusumoto Koetsu Takahashi 《Journal of Wood Science》2012,58(6):544-549
In order to find new utilization method of woody wastes, we examined the bioactivities of extracts from branch heartwood of Chamaecyparis obtusa (hinoki) and compared to extracts from trunk heartwood. The bioactivities examined were antifungal activities against four fungi (Trametes versicolor, Fomitopsis palustris, Trichoderma virens, Rhizopus oryzae), and bioassay with brine shrimp (Artemia salina) which shows any allelopathic activities not measurable with fungi. Antifungal activities were observed in the hexane and ethyl acetate extracts of branch and trunk heartwood. The hexane and ethyl acetate extracts of branch and hexane extract of trunk showed strong lethality against brine shrimp. The yields of the active extracts of branch were much more than that of trunk. The identified compounds in the active extracts of branch were germacra-1-(10),5-dien-4??-ol, t-cadinol, t-muurolol, hinokiresinol, and hinokinin. Hinokiresinol and t-muurolol showed strong antifungal activities. Hinokiresinol showed bioactivities against T. virens, R. oryzae and brine shrimp. Germacra-1-(10),5-dien-4??-ol was lethal to brine shrimp. Germacra-1-(10),5-dien-4??-ol and hinokiresinol were minor components in trunk heartwood, but major components in branch. These qualitative and quantitative results suggest that the branch heartwood could be a valuable chemical resource because it contains large amounts of antifungal and allelopathic compounds. 相似文献