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931.
Gibberellin A3 (GA3) treatment enhances the in vitro templateactivity of chromatin in peas (Pisum sativum, var. Alaska) (Tomiet al. 1983a). Effects of GA3 on the chromatin template weresurveyed for the chromatin components, DNA-tightly bound proteins(TBPs) and loosely bound proteins (LBPs). An addition of LBPsfrom GA3-treated chromatin enhanced the template activity ofLBP-depleted chromatin. In addition, both components of theLBPs, high mobility group proteins (HMGs) and low mobility groupproteins (LMGs) were required for this enhancement. The LBPsconverted LBP-depleted chromatin into a form susceptible toDNase I. LBPs probably are at least partly responsible for GA3-enhancedtemplate activity due to their relaxing the interaction of corehistones and DNA. (Received March 12, 1983; Accepted June 16, 1983) 相似文献
932.
During the period fromlate May through December 1981, tree-dwelling beetles were regularly surveyed at three deciduous oak
and two evergreen forests in the vicinity of Gifu City. Chrysomelidae and Curculionidae were abundant in these forests. The
species diversity and the seasonal succession of species were most apparent in May and June. The three deciduous oak forests,
with many species and high equitability, showed more diverse community structure, but fewer individuals, when compared with
the two evergreen forests. Furthermore, the species compositions of the deciduous oak forests were seasonally and spatially
more heterogeneous than those of the evergreen forests. A few dominant species, however, had a strong influence on the community
structure. The relationship between the diversity index and sample size was examined. The diversity index changed with the
sample size, and the range of the variation diminished as the sample size increased. However, equilibrium was not reached
even in the largest sample size used in this study (20 samples). There was a significantly high correlation (P<0.001) in diversity index between the smaller sample sizes (5, 10, 15) and the largest. It was, therefore, shown that community
structures can be compared on the basis of the diversity indices from samples of constant size, even when the samples are
small.
Contribution No. 108 from Lab. Ent., Fac. Agr., Gifu Univ. 相似文献
933.
Synovial Mononuclear Cells Consist with T Cells Which Produce High Levels of Tumor Necrosis Factor α
Hidenobu Akatsuka Mitsuo Okubo Hironori Ishida Katsumi Chiba Kenichi Imanishi Takehiko Uchiyama Kazuhiko Yamamoto Reiji Kasukawa Tomoe Nishimaki 《Microbiology and immunology》1997,41(4):367-370
To determine whether synovial mononuclear cells include a population of tumor necrosis factor α-produeing T cells, we measured tumor necrosis α levels in culture supernatants of synovial mononuclear cells by ELISA and analyzed tumor necrosis α mRNA-positive cell frequencies. There were no significant differences in the spontaneous levels of TNF α between synovial mononuclear cells and peripheral mononuclear cells. The frequency of tumor necrosis factor α mRNA-positive cells in synovial mononuclear cells was higher than that of peripheral mononuclear cells. When stimulated with a superantigen, mononuclear cells from the synovial fluid of rheumatoid arthritis patients showed higher levels of tumor necrosis factor α production (1,035 ± 817 pg/ml) than did mononuclear cells from their peripheral blood (236 ± 180 pg/ml). In addition, we observed that a few T cell clones were resistant to superantigenic restimulation in vitro. We conclude that when these types of T cells persist in the synovium, they play a role in the development of rheumatoid arthritis via a mechanism involving tumor necrosis factor α production. 相似文献
934.
935.
Hironori Toyama Kazuhiro Bessho Liangliang Huang Shun K. Hirota Yuichi Kano Keiko Mase Tatsuro Sato Akiyo Naiki Jianhua Li Yukihiro Shimatani Tetsukazu Yahara 《Freshwater Biology》2020,65(4):632-645
- Water pollution is one of the most serious aquatic environmental problems worldwide. In China, recent agricultural and industrial development has resulted in rapid changes in aquatic ecosystems. Here, we reveal the effects of water pollution on the phylogenetic community structure of aquatic macrophytes in the Tiaoxi River, China.
- We placed a rectangular plot at 47 sites within the Tiaoxi River from the mouth of the river to 88.5 km upstream, in which we recorded species abundance and measured 22 physico-chemical variables. Bayesian phylogeny using the rbcL and matK gene sequences was employed to quantify phylogenetic α- and β-diversity, and test the phylogenetic signal in four growth forms: emergent, floating-leaved, free-floating, and submerged.
- Within communities, water contamination and phytoplankton abundance decreased species richness and phylogenetic diversity, which resulted in phylogenetic clustering; species within communities were more closely related to each other than expected. Between communities, differences in geographical distance and phytoplankton abundance resulted in phylogenetic dissimilarity among plots. Aquatic macrophytes showed phylogenetic signals in which related species responded more similarly to disturbance.
- Thus, the observed patterns could be explained by environmental filtering and suggested that water pollution by human activity has added more filters to the existing environmental filters that drive the species assembly of macrophyte communities.
936.
Noboru Tanabe Junji Yamamoto Hiroaki Nishi Tomohiro Kudoh Yoshihiro Hamada Hironori Nakajo Hideharu Amano 《Cluster computing》2002,5(1):7-17
The communication architecture of the DIMMnet-1 network interface based on MEMOnet is described. MEMOnet is a class of a network interface plugged into a memory slot. This paper proposes three message transfer mechanisms named atomic on-the-fly sending (AOTF), block on-the-fly sending (BOTF) and OTF receiving with selective address translation. The DIMMnet-1 prototype will have an ASIC named Martini, two banks of PC133 based SO-DIMM slots and an 8 Gbps full duplex optical link. The software overhead incurred to generate a message is only 1 CPU cycle and the estimated hardware delay is 105 ns using AOTF. The estimated hardware delay for receiving to on chip memory using OTF receiver is 90 ns. The estimated achievable sending bandwidth of DIMMnet-1 using BOTF is 984 MB/s which was observed in our experiments. This bandwidth is 7.4 times higher than the maximum bandwidth of PCI. This high performance is available even when simultaneous sending and receiving are executed on a cheap personal computer with DIMM slots. This paper also discribes the effects of BOTF for a PCI-based NIC. 相似文献