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261.
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263.
Naohiro Takahashi Nobuyoshi Mikami Hirohiko Yamada Junshi Miyamoto 《Pest management science》1985,16(2):113-118
The hydrolysis of [14C] fenpropathrin ( I ) [(RS)-α-cyano-3-phenoxybenzyl 2,2,3,3-tetramethylcyclopropanecarboxylate] was studied in buffer solutions at pH 1.9–10.4, and in natural river and sea water at 25, 40, 55 and 65°C under laboratory conditions. The hydrolysis of I proceeded predominantly through neutral (pH independent) and base-catalysed processes in the regions below pH 3.9 and above pH 7.0, respectively, whereas both reactions occurred between pH 3.9 and 7.0. The rates of hydrolysis of I in buffer solutions were similar to those in one sample of river and one sample of sea water. If this obtains generally, it may be expected that the half-life of I in natural waters, normally within the range pH 5–9, will range from 1.54 to 1080 days at 40°C, 11.3 to 8520 days at 25°C and, by extrapolation of the data obtained in buffer solutions, 106 to 83 000 days at 10°C. The rate constants for hydrolysis of I in aqueous media can be expressed by: Where log kN = 9.60–(5.56 × 103 T?1) and log kB = 7.32–(2.56 × 103 T?1). The calculated rate constants were in good accord with the observed values in buffer solutions. Cleavage of the ester linkage was more rapid than hydration of the cyano group at any pH and temperature tested. 相似文献
264.
Katsuhiko Tsuruoka Takami Kurahara Hidenobu Kanamaru Hideyuki Takahashi Takafumi Gotoh 《Animal Science Journal》2019,90(5):637-648
This study evaluated the effects of condensed barley distillers soluble (CBDS) on growth rate, rumen fermentation, plasma metabolite, and myofiber properties, and gene expression related to metabolism in the skeletal muscles of Japanese Black calves, compared with soybean meal and corn. Twenty‐four calves were divided into four groups: fed 5% CBDS based on the hay dry matter weight (low CBDS) and fed soybean meal and corn at the same nutrition level (control); and fed 15% CBDS based on the hay dry matter weight (high CBDS) and fed soybean meal and corn at the same nutrition level (high soy). The daily gain was larger in the low (p = 0.08) and high (p < 0.05) CBDS groups compared with the control group. In the CBDS‐fed groups, plasma β‐hydroxybutyric acid concentrations were significantly higher at 6 months of age (p < 0.05), the percentage of type I myofibers was significantly lower and their diameters were significantly larger at 9 months of age (p < 0.05), and carnitine palmitoyltransferase 1b mRNA expression was significantly lower (p < 0.05) and citrate synthase mRNA expression tended to be lower (low; p = 0.06, high; p = 0.05) compared with control group. Thus, feeding CBDS promotes growth and leads to animals with more glycolytic and less oxidative muscle metabolism. 相似文献
265.
Tomoya Tamura Yuki Okubo Yoshitaka Deguchi Shizu Koshikawa Masahiro Takahashi Yasushi Chida Keiji Okada 《Animal Science Journal》2019,90(4):589-596
Demand has been increasing recently for an automated monitoring system of animal behavior as a tool for the management of livestock animals. This study investigated the association between the behavior of dairy cattle and the acceleration data collected using three‐axis neck‐mounted accelerometers, as well as the feasibility of improving the precision of behavior classifications through machine learning. In total 38 Holstein dairy cows were used, and kept in four different farms. A logger was mounted to each collar to obtain acceleration data for calculating the activity level and variations. At the same time the behavior of the cattle was observed visually. Characteristic acceleration waves were recorded for eating, rumination, and lying, respectively; and the activity level and variations were significantly different among these behaviors (p < 0.01). Decision tree learning was performed on the data set from Farm A and validated its precision; which proved to be 99.2% in cross‐validation, and 100% in test data sets from Farms B to D. This study showed that highly precise classifications for eating, rumination, and lying is possible by using decision tree learning to calculate the activity level and variations of cattle based on the data obtained by three‐axis accelerometers mounted to a collar. 相似文献
266.
Tsuyoshi Ito Yoshitaka Katoh Yuko Shimada Aya Ohnuma-Koyama Naofumi Takahashi Maki Kuwahara Takanori Harada 《Journal of toxicologic pathology》2016,29(1):39-43
Extraskeletal osteosarcoma is extremely rare in mice. This case report demonstrates a spontaneous murine extraskeletal osteosarcoma that exhibited various histological growth patterns in an ICR mouse. At necropsy, the tumor mass was located in the abdominal wall and was 45 × 30 × 25 mm in size. Histopathologically, the tumor showed the following four growth patterns: a solid pattern of polygonal cells embedded in an osteoid eosinophilic matrix with calcification, an irregular sheet pattern of short spindle cells accompanying some eosinophilic multinucleated cells, a fascicular pattern of spindle cells and a cystic pattern lined by short spindle cells. Immunohistochemically, most of the tumor cells were positive for vimentin, proliferating cell nuclear antigen and osterix. The multinucleated cells mentioned above were desmin positive and were regarded as regenerative striated muscles but not tumor cells. Since no clear continuity with normal bone tissues was observed, the tumor was diagnosed as an “extraskeletal osteosarcoma.” 相似文献
267.
Software development for estimating the concentration of radioactive cesium in the skeletal muscles of cattle from blood samples
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Tomokazu Fukuda Masahiro Hiji Yasushi Kino Yasuyuki Abe Hideaki Yamashiro Jin Kobayashi Yoshinaka Shimizu Atsushi Takahashi Toshihiko Suzuki Mirei Chiba Kazuya Inoue Yoshikazu Kuwahara Motoko Morimoto Masafumi Katayama Kenichiro Donai Hisashi Shinoda Tsutomu Sekine Manabu Fukumoto Emiko Isogai 《Animal Science Journal》2016,87(6):842-847
The 2011 earthquake severely damaged the Fukushima Daiichi Nuclear Power Plant (FNPP), resulting in the release of large quantities of radioactive material into the environment. The deposition of these radionuclides in rice straw as livestock feed led to the circulation of contaminated beef in the market. Based on the safety concern of the consumers, a reliable method for estimating concentrations of radioactive cesium in muscle tissue is needed. In this study, we analyzed the concentrations of radioactive cesium in the blood and skeletal muscle of 88 cattle, and detected a linear correlation between them. We then developed software that can be used to estimate radioactive cesium concentrations in muscle tissue from blood samples. Distribution of this software to the livestock production field would allow us to easily identify high‐risk cattle, which would be beyond the safety regulation, before shipping out to the market. This software is planned to be released as freeware. This software would contribute to food safety, and aid the recovery of the livestock industry from the damage creacted by the 2011 Tohoku earthquake and tsunami. 相似文献
268.
H. Takahashi K. Fujita C. Yoshida M. Nishihara 《The Journal of Horticultural Science and Biotechnology》2016,91(2):148-155
Gentians are alpine plants and two endemic species, Gentiana triflora and G. scabra, are cultivated as ornamentals in Japan. Because most of the Japanese cultivars are F1 hybrids, seed germination rate is an important factor for maintaining these cultivars. However, germination rates frequently differ among cultivars. Poor germination is a severe problem for gentian production, although there is almost no difference in their germination period and growth rate. In this study, we compared seed germination rates among three cultivars of G. triflora. A high rate of seed germination was observed in ‘Majel’ (MJ) and ‘Iwate’ (IW), but a low rate was recorded in ‘Iwate-Yumeminori’ (YM). We conducted a targeted metabolome analysis using these cultivars to elucidate the potential cause of inhibited seed germination. Multivariate analysis revealed that the aberrant accumulation of specific amino acids and a decrease in energy metabolites were observed in YM seed. Furthermore, protein concentrations and proteolytic activities in YM seed were lower than in MJ seed. These results imply that energy depletion was the main reason for the decreased rate of germination and that this depletion inhibited processes involved in seed germination, including de novo synthesis of the proteins necessary for germination. 相似文献
269.
Treatment with the MAPK kinase inhibitor U0126 during the first two hours of in vitro maturation improves bovine oocyte developmental competence
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T Shinohara Y Ohta N Kawate M Takahashi N Sakagami T Inaba H Tamada 《Reproduction in domestic animals》2018,53(1):270-273
This study examined the effects of treatment with U0126, which inhibits MAPK by inhibiting MAPK kinase, during the first 2 hr of in vitro maturation on bovine developmental competence and on gap junction (GAPJ) communication between the oocyte and cumulus cells. The percentage of oocytes developing to the blastocyst stage in the group treated with 5 μM U0126 (28%) was significantly higher than that in controls (15%, p < .05), while that in the group treated with 10 μM U0126 (18%) was not. Breakdown of the GAPJs was delayed in the group treated with 5 μM U0126 when compared to controls, as estimated by immunohistochemical examination of connexin 43, which is a primary constituent of the GAPJs. These results indicate that treatment with 5 μM U0126 during in vitro maturation delays GAPJ breakdown and improves bovine oocyte developmental competence. 相似文献
270.