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21.
Akutsu H Kikusui T Takeuchi Y Mori Y 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2003,65(9):1023-1025
Stress-induced hyperthermia is observed in animals exposed to stressful conditions. In our previous study, plant-derived fragrances such as green odor and alpha-pinene were shown to suppress this stress response in rats. In the present study, we examined the concentration-dependence of the alpha-pinene effects on stress-induced hyperthermia. Male rats carrying telemetry transmitters were transferred individually to a new cage containing bedding that had been sprayed with 0.3, 0.03, and 0.003% concentrations of alpha-pinene or control solvent. Following transfer to the novel environment, the body temperature increased significantly, and this response was clearly suppressed when the cage was scattered with 0.03% alpha-pinene only. These results suggest that the effect of alpha-pinene on stress-induced hyperthermia can be observed only at a certain concentration. 相似文献
22.
Sawada Y Yanai T Nakagawa H Tsukamoto Y Tamagawa Y Yokoi S Yanagi M Toya T Sugizaki H Kato Y Shirakura H Watanabe T Yajima Y Kodama S Masui A 《Pest management science》2003,59(1):49-57
Nineteen analogues were synthesized by modifying the tert-butylhydrazine moieties of N'-tert-butyl-N'-(3,5-dimethylbenzoyl)-5-methyl-2,3-dihydro-1,4-benzodioxine-6-carbohydrazide and N'-tert-butyl-N'-(3,5-dimethylbenzoyl)-5-methylchromane-6-carbohydrazide (chromafenozide), and the synthesized analogues were evaluated for their insecticidal activity against Spodoptera litura F. While all of the synthesized analogues had insecticidal activity inferior to those of the lead compounds, several of the analogues nonetheless showed high insecticidal activity. Chromafenozide has shown very high selectivity toward lepidopteran species. 相似文献
23.
K. Takeuchi H. Toyohara M. Kinoshita M. Sakaguchi 《Fish physiology and biochemistry》2000,23(2):173-182
We have isolated a cDNA encoding the taurine transporter from a tilapia (Oreochromis mossambicus) gill cDNA library. Transient expression of the cDNA in COS-7 cell indicates that the clone encodes a Na+- and Cl–-dependent and -amino acid-specific taurine transporter. By the transfer of tilapia cultured in freshwater to 70% artificial seawater, plasma osmolality increased by up to 100–135 mOsm/kgH2O along with the marked increase in the taurine transporter mRNA level in all the tissues examined i.e., kidney, stomach, intestine, gill, eye, liver, fin, muscle and brain. In most tissues, time-dependent change in the taurine transporter mRNA level corresponds to that in plasma osmolality. However, fin showed an acute and muscle showed a delayed increase in taurine transporter mRNA compared to changes in plasma osmolality. The taurine transporter mRNA level in tilapia embryos also increased after transfer from freshwater to 100% artificial seawater. Increase in taurine transporter expression leads to the activation of cellular uptake of taurine from plasma and the accumulation of taurine in the cell. Thus the results in the present study suggest that taurine plays an important role as an osmolyte in the ubiquitous tissues of tilapia during high-salinity adaptation. 相似文献
24.
Ogata N Hashizume C Momozawa Y Masuda K Kikusui T Takeuchi Y Mori Y 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2006,68(2):157-159
Excitatory amino acid transporters (EAATs) are important for terminating glutamatergic neurotransmission and protect central nervous system (CNS) neurons from glutamatergic excitotoxicity. We selected these genes as targets that may relate to canine behavioral traits. After screening four EAAT genes (glutamate transporter-1; GLT-1, excitatory amino acid transporter 4; EAAT4, excitatory amino acid carrier; EAAC1, glutamate/aspartate transporter; GLAST) for single nucleotide polymorphisms (SNPs), we identified two silent SNPs (C129T and T471C) in the GLT-1 gene. We genotyped 193 dogs of 5 breeds and found significant variation among breeds in these two SNPs in GLT-1. The C129T polymorphism was not observed in Malteses and Miniature Schnauzers. These results suggest that polymorphisms in the GLT-1 gene may be useful markers for examining how the genetic background relates to the behavioral traits of dogs. 相似文献
25.
Mora JR Iwata M Eksteen B Song SY Junt T Senman B Otipoby KL Yokota A Takeuchi H Ricciardi-Castagnoli P Rajewsky K Adams DH von Andrian UH 《Science (New York, N.Y.)》2006,314(5802):1157-1160
Normal intestinal mucosa contains abundant immunoglobulin A (IgA)-secreting cells, which are generated from B cells in gut-associated lymphoid tissues (GALT). We show that dendritic cells (DC) from GALT induce T cell-independent expression of IgA and gut-homing receptors on B cells. GALT-DC-derived retinoic acid (RA) alone conferred gut tropism but could not promote IgA secretion. However, RA potently synergized with GALT-DC-derived interleukin-6 (IL-6) or IL-5 to induce IgA secretion. Consequently, mice deficient in the RA precursor vitamin A lacked IgA-secreting cells in the small intestine. Thus, GALT-DC shape mucosal immunity by modulating B cell migration and effector activity through synergistically acting mediators. 相似文献
26.
Antagonism of medetomidine sedation by atipamezole in pigs. 总被引:1,自引:0,他引:1
R Nishimura H Kim S Matsunaga M Sakaguchi N Sasaki H Tamura A Takeuchi 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》1992,54(6):1237-1240
The efficacy of atipamezole as a medetomidine antagonist was evaluated in pigs. The atipamezole doses (intramuscularly) were 80, 160, 320 and 480 micrograms/kg of body weight, which were one, two, four and six times higher than the preceding medetomidine dose (80 micrograms/kg, intramuscularly). Atipamezole effectively reversed medetomidine-induced sedation, and the optimal action was seen at doses of 160 and 320 micrograms/kg. Recovery from sedation was quick and smooth, and adverse effects such as hyperactivity or tachycardia were minimal with either dose. 相似文献
27.
Komatsu Y Itoh N Taniyama H Kitazawa T Yokota H Koiwa M Ohtsuka H Terasaki N Maeno K Mizoguchi M Takeuchi Y Tanigawa M Nakamura T Watanabe H Matsuguchi Y Kukino T Honma A 《Journal of veterinary medicine. A, Physiology, pathology, clinical medicine》2002,49(9):482-486
Histopathological features of livers and blood chemical values in cows with abomasal displacement were investigated. Liver biopsy samples were collected during redressment operations in 92 cows with abomasal displacement, and the samples were stained with haematoxylin and eosin or periodic acid Schiff (PAS). Blood was collected for chemical tests. Livers were histopathologically divided into the following four types: normal histology cases (21%), fatty degeneration cases (36%), cloudy swelling cases (19%) and fatty degeneration cases with cloudy swelling (24%). The number of PAS-positive samples was significantly higher in the normal histology group and significantly lower in the severe fatty degeneration group and severe cloudy swelling group. Cows with fatty degeneration had significantly higher levels of serum 3-hydroxybutyric acid, non-esterified fatty acid and aspartate aminotransferase than did those with cloudy swelling or normal histology. The results indicate that the morbid conditions of cows with abomasal displacement can be classified into four types. 相似文献
28.
Inhibitory and promotive allelopathy in rice (Oryza sativa L.) 总被引:2,自引:1,他引:2
Studies on allelopathic rice, which inhibits the germination and development of weeds such as barnyardgrass ( Echinochloa spp.) and ducksalad [ Heteranthera limosa (Sw.) Wild.], have been strongly conducted in the USA, the Philippines, Japan, Korea, and other countries since the 1980s. Weed-suppressing rice plants can compete with weeds for light and mineral nutrients by their rapid and thick growth characteristics, and probably also by their allelopathic effects. It was suggested that allelopathic properties were inherited from parents. Different screening methods for finding allelopathic rice simply and rapidly have been proposed. In contrast, stimulative allelopathy in rice, which promotes germination of the dormant and dormancy-awakened seeds of Monochoria vaginalis (Burm. f.) Kunth var. vaginalis , has been investigated by the authors since the 1990s. Rice seeds promoted the germination in the dark and in light under submerged conditions. Our experiments suggested that rice seeds, hulls, plants and straw contain stimulative substance(s) that promote seed germination of M. vaginalis . 相似文献
29.
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