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排序方式: 共有460条查询结果,搜索用时 15 毫秒
81.
Toshiharu MITA Kazuhiko KONISHI Mamoru TERAYAMA Seiki YAMANE 《Entomological Science》2007,10(2):201-208
The family Megalyridae is recorded from Japan for the first time on the basis of two new species, Carminator helios and C. japonicus. This is the northernmost record of living Megalyridae, although fossil species are known from regions of the Baltic Sea. Carminator helios can be distinguished from congeners of the Asian and Australian regions by the combination of a long head, deeply excavated frons with convex inner margins, entirely striated postgena, the number of fore tibial spines (more than 16), and a long R1 vein. Carminator japonicus is distinguishable from other species by the combination of an orange‐colored metasoma, a weakly excavated frons, and an elongate vertex. This species was collected from the canopy of Acer pictum. Additional characters that distinguish species of the genus Carminator are discussed. 相似文献
82.
Shigeyuki Aoki Utako Kurosu Harunobu Shibao Seiki Yamane Takema Fukatsu 《Journal of Ethology》1998,16(2):91-96
The defensive behavior of the aphidDinipponaphis autumna, which forms small, completely closed galls on leaves ofDistylium racemosum, was observed. In mature galls, in addition to tens of mature or nearly mature aphids of the 3rd generation, there remained
3 – 17 1st-instar nymphs of the same generation, which had well-sclerotized legs and the antennae with developed setae. Despite
their minority, these 1st-instar nymphs clung to experimentally introduced insect larvae and stung them with their stylets.
Fourth-instar wingpadded nymphs, the majority of the 3rd generation at the experiment, also attacked the introduced larvae,
but they were readily spilt from the larvae. Four out of 205 1st-instar nymphs remaining in mature galls had the next instar
cuticle developing inside, indicating that they are not destined to be sterile. 相似文献
83.
Geotropic response of cucumber hypocotyls 总被引:5,自引:0,他引:5
Exogenous auxin applied to the apical bud of intact cucumberseedlings promoted elongation of the hypocotyl, mostly of theapical zone (zone I) and to a lesser extent, the middle andbasal zones (zones II and III). Geotropic curvature was clearlyobserved 30 min after geostimulation. The curvature began atzone I and moved toward the basal zones with prolonged geostimulation.Decapitation (removal of apex and cotyledons) did not produceany appreciable effect on the geotropic response, but the curvaturewas reduced with the removal of zone I. Auxin application toseedlings without zone I restored their ability to respond togravity. The lower epidermis of horizontally oriented hypocotylsplayed a more important role than the upper in the geotropicresponse. The extensibility of the lower epidermal cell wallwas increased significantly by the geostimulus before the onsetof the curvature response. (Received August 24, 1973; ) 相似文献
84.
Homma Kosuke Akashi Nobuhiro Abe Tomoyuki Hasegawa Mikio Harada Kenichi Hirabuki Yoshihiko Irie Kiyoshi Kaji Mikio Miguchi Hideo Mizoguchi Noriyasu Mizunaga Hiromi Nakashizuka Tohru Natume Syunji Niiyama Kaoru Ohkubo Tatsuhiro Sawada Shin-ichi Sugita Hisashi Takatsuki Seiki Yamanaka Norikazu 《Plant Ecology》1999,140(2):129-138
The causes and timing of seed death in early regeneration process of Siebold's beech (Fagus crenata Blume) was studied at 15 sites along a snowfall gradient in Japan, in order to clarify why the seedling density of the species has geographic difference remarkably. Seed production did not significantly differ along the snowfall gradient. Pre-dispersal seed mortality by insect damage was higher at sites with light snowfall than at sites with heavy snowfall, but this only seemed to be a minor factor influencing the population. A large proportion of the viable nuts that fall in autumn ware killed in winter before germination. Winter mortality was much higher at sites with thin snow cover than that at sites with thick snow cover, and this factor was strongly correlated with the geographic variation of seedling regeneration probability. There was little seed mortality by winter desiccation. The main factor contributing to the geographic difference seemed to be a seed predation by rodents in winter. Deep snow cover may reduce the success of rodents finding seeds in winter. Thus the observed relationship between snowpack depth and early mortality may be due to an indirect effect through the process of seed predation.p> 相似文献
85.
Tensho Ten Satoru Nagatoishi Ryo Maeda Masaru Hoshino Yoshiaki Nakayama Motoharu Seiki Takeharu Sakamoto Kouhei Tsumoto 《The Journal of biological chemistry》2021,297(5)
Mint3 is known to enhance aerobic ATP production, known as the Warburg effect, by binding to FIH-1. Since this effect is considered to be beneficial for cancer cells, the interaction is a promising target for cancer therapy. However, previous research has suggested that the interacting region of Mint3 with FIH-1 is intrinsically disordered, which makes investigation of this interaction challenging. Therefore, we adopted thermodynamic and structural studies in solution to clarify the structural and thermodynamical changes of Mint3 binding to FIH-1. First, using a combination of circular dichroism, nuclear magnetic resonance, and hydrogen/deuterium exchange–mass spectrometry (HDX-MS), we confirmed that the N-terminal half, which is the interacting part of Mint3, is mostly disordered. Next, we revealed a large enthalpy and entropy change in the interaction of Mint3 using isothermal titration calorimetry (ITC). The profile is consistent with the model that the flexibility of disordered Mint3 is drastically reduced upon binding to FIH-1. Moreover, we performed a series of ITC experiments with several types of truncated Mint3s, an effective approach since the interacting part of Mint3 is disordered, and identified amino acids 78 to 88 as a novel core site for binding to FIH-1. The truncation study of Mint3 also revealed the thermodynamic contribution of each part of Mint3 to the interaction with FIH-1, where the core sites contribute to the affinity (ΔG), while other sites only affect enthalpy (ΔH), by forming noncovalent bonds. This insight can serve as a foothold for further investigation of intrinsically disordered regions (IDRs) and drug development for cancer therapy. 相似文献
86.
87.
Temporal changes in food availability affect foraging success and ultimately reproductive success of animals. They include
both seasonal and annual changes. Although many researchers have investigated food availability and the corresponding ranging
behavior of primates, studies of yearly changes have been limited. We studied the effects of the fruiting of nuts of Fagus crenata, Zelkova serrata, and Torreya nucifera on the ranging behavior of Japanese macaques (Macaca fuscata) in autumn on Kinkazan Island, northern Japan, for 5 yr between 2000 and 2005 (excluding 2003). We divided the study area
(3.3 km2) into 100 × 100-m quadrats to assess the distribution of nut-rich quadrats that contained high densities of nut-producing
species. The home ranges of the monkeys contained more nut-rich quadrats than expected, and the difference was significant
for 3 of 5 yr. Autumn home-range use was also affected by the distribution of nut production, although the effect differed
by year: monkeys frequently used nut-rich quadrats in a Zelkova-year (2000) and in 1 Torreya-year (2001), whereas they nonselectively used nut-rich quadrats in 2 Fagus-years (2002 and 2005) and in another Torreya-year (2004). Thus, Japanese macaques flexibly change their autumn ranging behavior according to yearly changes in distribution
of nut production. 相似文献
88.
89.
Onozuka I Kakinuma S Kamiya A Miyoshi M Sakamoto N Kiyohashi K Watanabe T Funaoka Y Ueyama M Nakagawa M Koshikawa N Seiki M Nakauchi H Watanabe M 《Biochemical and biophysical research communications》2011,406(1):134-140
Matrix metalloproteinase (MMP) plays an important role in homeostatic regulation of the extracellular environment and degradation of matrix. During liver fibrosis, several MMPs, including MMP-2, are up-regulated in activated hepatic stellate cells, which are responsible for exacerbation of liver cirrhosis. However, it remains unclear how loss of MMP-2 influences molecular dynamics associated with fibrogenesis in the liver. To explore the role of MMP-2 in hepatic fibrogenesis, we employed two fibrosis models in mice; toxin (carbon tetrachloride, CCl4)-induced and cholestasis-induced fibrosis. In the chronic CCl4 administration model, MMP-2 deficient mice exhibited extensive liver fibrosis as compared with wild-type mice. Several molecules related to activation of hepatic stellate cells were up-regulated in MMP-2 deficient liver, suggesting that myofibroblastic change of hepatic stellate cells was promoted in MMP-2 deficient liver. In the cholestasis model, fibrosis in MMP-2 deficient liver was also accelerated as compared with wild type liver. Production of tissue inhibitor of metalloproteinase 1 increased in MMP-2 deficient liver in both models, while transforming growth factor β, platelet-derived growth factor receptor and MMP-14 were up-regulated only in the CCl4 model. Our study demonstrated, using 2 experimental murine models, that loss of MMP-2 exacerbates liver fibrosis, and suggested that MMP-2 suppresses tissue inhibitor of metalloproteinase 1 up-regulation during liver fibrosis. 相似文献
90.
Sumida M Satou N Yoshikawa N Kurabayashi A Islam MM Igawa T Oumi S Katsuren S Ota H Shintani N Fukuniwa H Sano N Fujii T 《Zoological science》2011,28(11):834-839
Odorrana ishikawae is listed as a class IB endangered species in the IUCN Red List and is protected by law in both Okinawa and Kagoshima Prefectures, Japan. Here, in an effort to help effectively preserve the genetic diversity of this endangered species in the laboratory, we tested a farming technique involving the artificial breeding of frogs, and also promoted natural breeding in the laboratory. Field-caught male/female pairs of the Amami and Okinawa Island populations were artificially bred using an artificial insemination method in the 2004, 2006, and 2008 breeding seasons (March to April). Although fewer than 50% of the inseminated eggs achieved metamorphosis, approximately 500, 300, and 250 offspring from the three respective trials are currently being raised in the laboratory. During the 2009 and 2010 breeding seasons, second-generation offspring were produced by the natural mating activities of the first offspring derived from the two artificial matings in 2004. The findings and the methods presented here appear to be applicable to the temporary protection of genetic diversity of local populations in which the number of individuals has decreased or the environmental conditions have worsened to levels that frogs are unable to survive by themselves. 相似文献