A Mutant of Hog Cholera Virus in the Virus-Carrier Cell Cultivated at a Lower Temperature     

Hisao Izawa  Toshihiko Nagabayashi  Masao Soekawa 《Zoonoses and public health》1971,18(3):197-204

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Temperature dependence of the dynamic viscoelasticity of bases of Japanese cypress branches and the trunk close to the branches saturated with water     

Yuzo Furuta  Toshihiko Okuyama  Keisuke Kojiro  Yuka Miyoshi  Tomoaki Kiryu 《Journal of Wood Science》2014,60(4):249-254

With the aim of obtaining findings on the dynamic properties of branches and their bases, as well as their support mechanisms, the present study examined the temperature dependence of the dynamic viscoelasticity of Japanese cypress samples saturated with water to clarify the responses in different regions, and identified factors influencing the characteristics. In the bases of the branches: E′ sharply decreased at approximately room temperature and significantly decreased at around 20 and 60 °C; a peak and shoulder peak of E″ or tan δ were noted at around 20 °C, and there was another peak of tan δ at around 60–80 °C; and mechanical relaxation was noted at around 20 °C and 60–80 °C. On the other hand, in some regions, including the trunks, branches, and their bases, mechanical relaxation was only noted on the high-temperature side. However, boiling treatment with about 12 % weight loss inhibited mechanical relaxation, and there were decreases in E′, E″, and tan δ at approximately room temperature. The bases of the branches of Japanese cypress are considered to develop its elasticity and viscosity to tolerate external stress by accumulating an extract, which enhances the strength of lignin.  相似文献   

Effects of thyroid hormone on gonadotropin-induced steroid production in medaka,Oryzias latipes,ovarian follicles     

Kiyoshi Soyano  Toshihiko Saito  Masaki Nagae  Kohei Yamauchi 《Fish physiology and biochemistry》1993,11(1-6):265-272

Blood and ovarian samples were collected at intervals of 4h prior to spawning time from medaka (Oryzias latipes) that were maturationally synchronized with artificial photoperiod (14h light: 10h dark). Plasma estradiol-17β (E₂) levels increased rapidly from 16h before spawning and peaked at 8h before spawning. Follicle-enclosed oocytes (ovarian follicles) at different stages of development were isolated from the ovaries and used to study the in vitro effects of thyroid hormone (triiodothyronine; T₃) on pregnant mare serum gonadotropin (GTH)-induced E₂ production. GTH at a concentration of 100 IU/ml stimulated E₂ production by ovarian follicles collected between 32 and 16h before spawning. At 32h before spawning, T₃ (5 ng/ml) administered along with GTH (100 IU/ml) resulted in a 3.5 fold increase in E₂ production, compared with GTH administered alone. These results suggest that T₃ can act on ovarian follicles directly to modulate GTH-stimulated E₂ production in the medaka.  相似文献   

Larvicidal and adulticidal activity of alkylphthalide derivatives from rhizome of Cnidium officinale against Drosophila melanogaster   总被引：1，自引：0，他引：1  

Tsukamoto T  Ishikawa Y  Miyazawa M 《Journal of agricultural and food chemistry》2005,53(14):5549-5553

The insecticidal activity of the chloroform extract of Cnidium officinale rhizomes and its constituents was investigated against larvae and adults of Drosophila melanogaster and compared with that of rotenone. Bioassay-guided isolation of the chloroform extract of C. officinale resulted in the isolation and characterization of four alkylphthalides, cnidilide (1), (Z)-ligustilide (2), (3S)-butylphthalide (3), and neocnidilide (4). The structures of these compounds were established by spectroscopic analysis. The isolated compounds 2, 3, and 4 exhibited LC50 values of 2.54, 4.99, and 9.90 micromol/mL of diet concentration against larvae of D. melanogaster, respectively. Against both sexes (males/females, 1:1) of adults (5-7 days old), compound 3 showed the most potent activity of the compounds isolated with the LD50 value of 5.93 microg/adult, comparable to that of rotenone (LD50 = 3.68 microg/adult). Structure-activity relationships of phthalides isolated suggest that the presence of conjugation with the carbonyl group in the lactone ring appeared to play an important role in the larvicidal activity. Acetylcholinesterase (prepared from the adult heads of D. melanogaster) inhibitory activity was also investigated in vitro to determine the insecticide mode of action for the acute adulticidal activity.  相似文献   

Weak interplate coupling by seamounts and repeating M approximately 7 earthquakes     

Mochizuki K  Yamada T  Shinohara M  Yamanaka Y  Kanazawa T 《Science (New York, N.Y.)》2008,321(5893):1194-1197

Subducting seamounts are thought to increase the normal stress between subducting and overriding plates. However, recent seismic surveys and laboratory experiments suggest that interplate coupling is weak. A seismic survey in the Japan Trench shows that a large seamount is being subducted near a region of repeating earthquakes of magnitude M approximately 7. Both observed seismicity and the pattern of rupture propagation during the 1982 M 7.0 event imply that interplate coupling was weak over the seamount. A large rupture area with small slip occurred in front of the seamount. Its northern bound could be determined by a trace of multiple subducted seamounts. Whereas a subducted seamount itself may not define the rupture area, its width may be influenced by that of the seamount.  相似文献   

Integrated field- and model-based study of hydro-environmental aspects of a small, endangered wetland in eastern Hokkaido, Japan     

Takeo Tsuchihara  Satoshi Ishida  Masayuki Imaizumi  Toshihiko Kawachi 《Paddy and Water Environment》2006,4(3):125-137

The hydro-environmental aspects of a small, endangered wetland (Totsuru wetland), located in eastern Hokkaido, Japan, are investigated, and the efficacy of a proposed engineering strategy for restoring the wetland is examined. Taking ²²²Rn as a target tracer and building a static ²²²Rn mass balance equation, the share of groundwater-genetic surface water in yielding the entire surface water in the wetland is appraised. The share is also appraised by using a different approach based on a non-static, site-specific water balance model. Both approaches yielded nearly the same percentage share, and therefore, it is concluded that 70% or more of the surface water entering the Totsuru swamp through the natural rivers is groundwater genetic. Using the water balance model, it is deduced that the reverse flow from the Uenbetsu drainage river is not less than 30% of the entire surface water flow entering the swamp, and therefore contributes considerably to mitigating the shrinkage of the swamp. Finally, through numerical experiments, it is shown that raising the water level of the Uenbetsu drainage river with a constructed weir to enhance the reverse flow is efficacious for restoring the wetland.  相似文献   

Natural and experimental evidence of melt lubrication of faults during earthquakes     

Di Toro G  Hirose T  Nielsen S  Pennacchioni G  Shimamoto T 《Science (New York, N.Y.)》2006,311(5761):647-649

Melt produced by friction during earthquakes may act either as a coseismic fault lubricant or as a viscous brake. Here we estimate the dynamic shear resistance (tau(f)) in the presence of friction-induced melts from both exhumed faults and high-velocity (1.28 meters per second) frictional experiments. Exhumed faults within granitoids (tonalites) indicate low tau(f) at 10 kilometers in depth. Friction experiments on tonalite samples show that tau(f) depends weakly on normal stress. Extrapolation of experimental data yields tau(f) values consistent with the field estimates and well below the Byerlee strength. We conclude that friction-induced melts can lubricate faults at intermediate crustal depths.  相似文献   

A case of spontaneous autoimmune skin disease in a cynomolgus monkey (Macaca fascicularis)     

Shinichi Onishi  Minto Nakagawa  Saori Matsuo  Junko Shinozuka  Mio Hiramatsu  Takehito Isobe  Toshihiko Watanabe  Atsuhiko Kato 《Journal of toxicologic pathology》2022,35(1):103

Pemphigus is an autoimmune blistering disease characterized by lesions on the skin and mucous membranes. To date, no spontaneous cases of this disease have been reported in cynomolgus monkeys. This report describes the histopathological characteristics of spontaneous pemphigus in a cynomolgus monkey. Macroscopically, redness and scaling with pruritus were observed on the skin of the entire body. Histopathologically, the epidermis showed intercellular edema, and eosinophils and mononuclear cells infiltrated the epidermis. There was no obvious acantholysis in the epidermis. The perivascular area showed edema, and eosinophils and mononuclear cells infiltrated the vessels in the dermis. Immunohistochemically, the intercellular area in the epidermis was positive for Immunoglobulin G and Complement component 3. Serologically, anti-desmoglein 1 and desmoglein 3 antibodies in the serum were negative. From these findings, this case was diagnosed as an autoimmune skin disease, suspected to be pemphigus, and concluded as lesions being similar to those in human “pemphigus herpetiformis”.  相似文献   

Can research on the early marine life stage of juvenile chum salmon <Emphasis Type="Italic">Oncorhynchus keta</Emphasis> forecast returns of adult salmon? A case study from eastern Hokkaido,Japan     

Toshihiko Saito  Ikutaro Shimizu  Jiro Seki  Toshiki Kaga  Eiichi Hasegawa  Hiromi Saito  Kazuya Nagasawa 《Fisheries Science》2010,76(6):909-920

To examine the efficacy of juvenile salmon research as a tool for forecasting adult returns, the results from a study on the early marine life stage of juvenile chum salmon, conducted in the Nemuro Strait during 1999–2002 (i.e., 1998–2001 brood years), were compared with the return rates of adult salmon. Among the four brood years, the 2000 brood year (i.e., salmon migrating to the sea in 2001) was previously reported as showing higher abundance, higher growth rate and better somatic condition during the coastal residency period. Consequently, we expected it to have the highest return rate, under a hypothesis that juvenile survival in coastal residency regulates brood-year strength. Contrary to this expectation, the 2000 brood year had almost the lowest return rate. Alternatively, a statistical model in which sea surface temperature during the first year of marine life and size at release were utilized as explanatory variables reconstructed the actual variability in return rates more accurately than that based on the early marine life stage. Possible reasons for the discrepancy between the results of the juvenile salmon research and adult returns are discussed, and we suggest improvements for future research on juvenile salmon.  相似文献   

Prebiotic effect of glycerol galactoside isolated from color-faded nori in rats     

Kenji Ishihara  Chiaki Oyamada  Yoko Sato  Toshiyuki Suzuki  Masaki Kaneniwa  Hiromi Kunitake  Toshihiko Muraoka 《Fisheries Science》2010,76(6):1015-1021

Glycerol galactoside (GG; floridoside: 2-O-glycerol-α-d-galactopyranoside, and isofloridoside: 1-O-glycerol-α-d-galactopyranoside) is known to be a component of edible red seaweed nori. Recently, we have found that low-quality nori (color-faded nori), which has a low protein content, contains a large quantity of GG. From further studies, we have also found that GG has prebiotic characteristics in vitro. In this study, we evaluated the in vivo prebiotic activity of GG in rats. Dietary GG selectively increased the cecal Bifidobacterium count in rats. Other indices of prebiotics, such as pH of cecal content, organic acid concentrations, and fecal weight, also supported the existence of prebiotic activity of GG. The present data will also contribute to the development of a new method of utilizing color-faded nori as a health-promoting foodstuff.  相似文献