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171.
Capsule Divorce in Barn Swallows could be explained by the mechanism of asynchronous arrival of mates. 相似文献
172.
Masamitsu Konno Atsushi Hamabe Shinichiro Hasegawa Hisataka Ogawa Takahito Fukusumi Shimpei Nishikawa Katsuya Ohta Yoshihiro Kano Miyuki Ozaki Yuko Noguchi Daisuke Sakai Toshihiro Kudoh Koichi Kawamoto Hidetoshi Eguchi Taroh Satoh Masahiro Tanemura Hiroaki Nagano Yuichiro Doki Masaki Mori Hideshi Ishii 《Development, growth & differentiation》2013,55(3):309-318
Adipose tissue‐derived mesenchymal stem cells (ADSCs) are multipotent and can differentiate into various cell types, including osteocytes, adipocytes, neural cells, vascular endothelial cells, cardiomyocytes, pancreatic β‐cells, and hepatocytes. Compared with the extraction of other stem cells such as bone marrow‐derived mesenchymal stem cells (BMSCs), that of ADSCs requires minimally invasive techniques. In the field of regenerative medicine, the use of autologous cells is preferable to embryonic stem cells or induced pluripotent stem cells. Therefore, ADSCs are a useful resource for drug screening and regenerative medicine. Here we present the methods and mechanisms underlying the induction of multilineage cells from ADSCs. 相似文献
173.
174.
Hiroto Tamura Maiko Yoshioka Momoko Hasegawa Akifumi Hosoda Masato Matsugi Miki Akamatsu 《Bioorganic & medicinal chemistry》2013,21(11):2968-2974
Although flavones act as potent androgen receptor (AR) antagonists, it remains unclear how flavones interact with AR. The aim of this in silico study was to investigate the molecular recognition processes of newly synthesized 5,4′-difluoroflavone with the highest activity (IC50 value = 0.19 μM) in the AR-ligand binding domain (AR-LBD). The results demonstrated that at its 4′-position of 5,4′-difluoroflavone the substituents may face Arg752 and that in AR-LBD, the submolecular bulk of substituents is unfavorable for AR antagonists and the negative electrostatic interaction site prefers the stronger hydrogen bond capability of substituents of AR antagonists. The prediction model is a valuable tool for designing a novel AR antagonist. 相似文献
175.
Kenji Seiwa Yoshiko Miwa Shigetoshi Akasaka Hiroshi Kanno Mizuki Tomita Tomoyuki Saitoh Naoto Ueno Megumi Kimura Yoichi Hasegawa Miki Konno Kazuhiko Masaka 《Ecological Research》2013,28(1):29-41
To evaluate the extent to which landslides affect community dynamics and consequent species diversity in a beech-dominated forest, differences in the composition and size structure of tree species were compared between landslide and adjacent stable (control) stands. Demography and changes in size were compared between the two stands over a 5-year period about 60 years after a landslide. In the control stand, replacement occurred even amongst late-successional species, with beech (Fagus crenata)—the most dominant species—increasing in relative abundance. In the landslide stand, very few large individuals of late-successional species occurred, whereas large individuals of early-successional species occurred only in the landslide stand. The traits indicate that the landslide strongly facilitated species diversity, not only by reducing the dominance of late-successional species, but also by promoting recruitment of early-successional species. However, new recruitment of early-successional species was inhibited in the landslide stand, although we observed succeeding regeneration and subsequent population growth of late-successional species there. As a result, the relative dominance of late-successional species increased with succession after the landslide, thus decreasing future species diversity. In beech-dominant forest landscapes in Japan that include communities with different developmental stages, the mosaic of serial stages may facilitate species diversity after a landslide. 相似文献
176.
Hiroyuki Nishimura Hiromasa Hasegawa Akira Seo Hidenori Nakano Junya Mizutani 《Bioscience, biotechnology, and biochemistry》2013,77(11):2397-2398
A monohalomethane-producing enzyme, S-adenosyl-L-methionine-dependent halide ion methyltransferase (EC 2.1.1.-) was purified from the marine microalga Pavlova pinguis by two anion exchange, hydroxyapatite and gel filtration chromatographies. The methyltransferase was a monomeric molecule having a molecular weight of 29,000. The enzyme had an isoelectric point at 5.3, and was optimally active at pH 8.0. The Km for iodide and SAM were 12 mM and 12 μM, respectively, which were measured using a partially purified enzyme. Various metal ions had no significant effect on methyl iodide production, suggesting that the enzyme does not require metal ions. The enzyme reaction strictly depended on SAM as a methyl donor, and the enzyme catalyzed methylation of the I-,Br-, and Cl- to corresponding monohalomethanes and of bisulfide to methyl mercaptan. 相似文献
177.
Yoshinobu Katoh Tadao Hasegawa Takao Suzuki Taro Fujii 《Bioscience, biotechnology, and biochemistry》2013,77(8):2185-2190
During differentiation after auxin withdrawal, the change in the ethylene production of Hiproly barley callus paralleled the change in 1-aminocyclopropane-1-carboxylic acid (ACC) content. The levels of ACC and ethylene production decreased rapidly, and then increased in Hiproly barley callus.Aminooxyacetic acid (AOA) prevented the ACC and ethylene production of the callus. Moreover, aminoisobutyric acid (AIB) also inhibited the ethylene production, but did not prevent the ACC synthesis of the callus. On the other hand, methylglyoxal-bis(guanylhydrazone) (MGBG) greatly enhanced the ACC and ethylene production. Formation of adventitious roots in Hiproly barley callus was enhanced by the cultivation in the medium containing AIB or AOA. However, differentiation of the callus was strongly inhibited by MGBG.Thus, prevention of ethylene production may be significant for differentiation of Hiproly barley callus. 相似文献
178.
Akira Hasegawa Daikichi Nishimura Takashi Kurokawa Minoru Nakajima 《Bioscience, biotechnology, and biochemistry》2013,77(10):1773-1776
Paromamine and its related compounds were synthesized by a modified Königs-Knorr reaction of 3,4,6-tri-O-acetyl-2-(2′,4′-dinitroanilno)-α-d-glucopyranosyl bromide with isopropylidene derivatives of 2-deoxystreptamine, streptamine and dihydroconduramine F–4. The condensed products were isolated as their poly N-acetyl derivatives and proved to have α-configuration by PMR spectroscopy in D2O. 相似文献
179.
180.
Kohei Oda Takanori Nakazima Takao Terashita Ken-ichiro Suzuki Sawao Murao 《Bioscience, biotechnology, and biochemistry》2013,77(11):3073-3080
A S-PI(Pepstatin Ac)-insensitive carboxyl proteinase was found in culture filtrate of a Xanthomonas sp. bacterium. The carboxyl proteinase was highly purified and about 100 mg of the enzyme was obtained from 601 of culture filtrate, with a recovery of 25%. The optimum condition for the action of the purified enzyme toward casein was approx. pH 2.7 and its activity was not inhibited by any of such carboxyl proteinase inhibitors as Pepstatin, S-PI, and DAN but EPNP inhibited it. Such behavior of the enzyme against inhibitors resembles that of Pseudomonas sp. carboxyl proteinase, the first found from a bacterium. Some differences were observed, however, in their properties such as optimum pH, isoelectric point, and amino acid composition. 相似文献