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991.
Male songbirds approach females by using their songs. Knowing what females perceive and prefer in male songs is an important
aspect of understanding courtship behavior. Male Bengalese finches (Lonchura striata var. domestica) sing complex sequence patterns with their own variety of elements. We tested female preference with phonologically different
songs and sequentially different songs using an operant selection task. In the first experiment we presented the father’s
song and an unfamiliar song that were phonologically different. Females clearly preferred the father’s song over a novel song.
In the second experiment, we used the father’s song and its element order reversed song to test female preference for the
difference in element sequence. In the third experiment, we presented different sequence complexity songs edited from the
same unfamiliar song elements to test female preference for complex sequence. Females did not show a significant preference
in either the second or third experiment. Results show that female Bengalese finches discriminated the difference in song
elements, preferred familiar songs, and did not show preference for difference of sequence. This study did not support evidence
that female Bengalese finches prefer a complex sequence. However, in future research, we should carefully investigate female
preference for choosing mates in a natural context. 相似文献
992.
Hiroyuki Tobita Shigeaki F. Hasegawa Xingjun Tian Satoshi Nanami Hiroshi Takeda 《Symbiosis (Philadelphia, Pa.)》2010,50(1-2):77-86
To estimate nodule biomass of Alnus hirsuta var. sibirica, an N2-fixing tree species, we examined the distribution pattern and size structure of nodules in a 17 to 18 year old stand naturally regenerated after disturbance by road construction in Japan. Nodules were harvested within 1 m from the outer edge of stems of plants with different sizes on four occasions from June to October. The diameter of the subtending root at the base of each nodule and nodule dry weight were measured in 20 cm increments outwards from the base of each stem. Horizontal distribution of nodules around each tree varied greatly among tree diameters at 1.3 m (dbh) within the even-aged stand. In particular, smaller individuals had a concentrated distribution of nodules close to the stem. Nodule abundance occurred further from the stems with increasing tree size. Nodule biomass within 1 m from the outer edge of individual stems increased with tree size ([nodule biomass] = 0.442 [dbh]2.01, R 2?=?0.747, P?<?0.05). By using the relationship, nodule biomasses were estimated to be 84.1 kg ha?1. These results suggest that it is necessary to take into account tree size and patterns of tree distribution in nodule biomass estimates. 相似文献
993.
Masaaki Minami Yukio Wakimoto Masakado Matsumoto Hideyuki Matsui Yasue Kubota Atsushi Okada Masanori Isaka Ichiro Tatsuno Yasuhito Tanaka Tadao Hasegawa 《Current microbiology》2010,61(2):101-105
Streptococcus pyogenes is indigenous to the human pharynx and causes acute pharyngitis. Balanoposthitis is an inflammatory disease of the glans
and the foreskin. However, balanoposthitis caused by S. pyogenes is not widely recognized as a sexually transmitted disease. In addition, bacteriological features of the isolates causing
balanoposthitis are unclear. The four S. pyogenes strains isolated from adult balanoposthitis were examined. We performed emm typing, T antigen typing, RAPD assay, PCR assay for the streptococcal pyrogenic exotoxin-related genes and antibiotic-resistant
genes, and antibiotic susceptibility assay. All four strains were suspected to be transmitted by penile-oral sexual intercourse,
were found to be different by genetic analysis, and also harbored some antibiotic-resistant factors. We propose that S. pyogenes should be considered as a causative agent of sexually transmitted disease. The drug resistant S. pyogenes must be taken into account when balanoposthitis patients are treated with antibiotic. 相似文献
994.
995.
Tomoharu Iino Noriaki Hashimoto Takuro Hasegawa Masato Chiba Jun-ichi Eiki Teruyuki Nishimura 《Bioorganic & medicinal chemistry letters》2010,20(5):1619-1622
Glucokinase activators (GKAs) are currently under investigation as potential antidiabetic agents by many pharmaceutical companies. Most of GKAs reported previously possess N-aminothiazol-2-yl amide moiety in their structures because the aminothiazole moiety interacts with glucokinase (GK) and shows strong GK activation. During the development of N-aminothiazol-2-yl amide derivatives, we identified a bioactivation and metabolic liability of 2-aminothizole substructure of GKA 3 by assessing covalent binding, metabolites in liver microsomes and glutathione (GSH) trap assay. 相似文献
996.
Two LysM receptor molecules, CEBiP and OsCERK1, cooperatively regulate chitin elicitor signaling in rice 总被引:6,自引:0,他引:6
Shimizu T Nakano T Takamizawa D Desaki Y Ishii-Minami N Nishizawa Y Minami E Okada K Yamane H Kaku H Shibuya N 《The Plant journal : for cell and molecular biology》2010,64(2):204-214
Chitin is a major molecular pattern for various fungi, and its fragments, chitin oligosaccharides, are known to induce various defense responses in plant cells. A plasma membrane glycoprotein, CEBiP (chitin elicitor binding protein) and a receptor kinase, CERK1 (chitin elicitor receptor kinase) (also known as LysM-RLK1), were identified as critical components for chitin signaling in rice and Arabidopsis, respectively. However, it is not known whether each plant species requires both of these two types of molecules for chitin signaling, nor the relationships between these molecules in membrane signaling. We report here that rice cells require a LysM receptor-like kinase, OsCERK1, in addition to CEBiP, for chitin signaling. Knockdown of OsCERK1 resulted in marked suppression of the defense responses induced by chitin oligosaccharides, indicating that OsCERK1 is essential for chitin signaling in rice. The results of a yeast two-hybrid assay indicated that both CEBiP and OsCERK1 have the potential to form hetero- or homo-oligomers. Immunoprecipitation using a membrane preparation from rice cells treated with chitin oligosaccharides suggested the ligand-induced formation of a receptor complex containing both CEBiP and OsCERK1. Blue native PAGE and chemical cross-linking experiments also suggested that a major portion of CEBiP exists as homo-oligomers even in the absence of chitin oligosaccharides. 相似文献
997.
Shigehiko Uni Tomoyuki Boda Koichi Daisaku Yoshihiro Ikura Haruhiko Maruyama Hideo Hasegawa Masako Fukuda Hiroyuki Takaoka Odile Bain 《Parasitology international》2010,59(3):477-480
A female of Onchocerca sp. was found to be the probable causative agent of a subcutaneous nodule in the left knee of a 70-year-old man in a rural area of Hiroshima Prefecture, Honshu, the main island of Japan. We compared the characteristics of the agent with the features of the four previously suspected species found in cattle and horses in various parts of the world, as well as O. lupi and O. jakutensis that were suspected or proved, respectively, in zoonotic cases in Europe. In addition, the morphologic characteristics of this parasite were compared with those of the four Onchocerca species found in wild animals in Japan. Based on such characteristics as the large triangle ridges, the considerable distance between any two adjacent ridges, and the absence of inner cuticular striae in the longitudinal sections, we found the causative agent in the present case to be identical to the female of Onchocerca dewittei japonica. All five previous cases of zoonotic onchocerciasis in Japan had been found in Oita, Kyushu, the main southern island. This human case caused by O. dewittei japonica suggests that zoonotic onchocerciasis is liable to occur in rural areas in Japan where wild boar, Simulium vectors, and humans overlap. 相似文献
998.
Sources of organic carbon and depositional environment in the Bengal delta plain sediments during the Holocene period 总被引:1,自引:0,他引:1
Hossain M. Anawar Takahito Yoshioka Eiichi Konohira Junji Akai M. C. Freitas Shafi M Tareq 《Limnology》2010,11(2):133-142
This study investigated the sources of organic matter and sediment depositional environment within fluviatile sediments of
the Ganges–Meghna (GM) delta plains. The very low contents of trace metals e.g., chromium (Cr), cobalt (Co), scandium (Sc),
and vanadium (V), organic carbon content, and cerium (Ce)-anomaly data of sediments indicate the redox conditions that fall
within the boundary of oxic–anoxic condition, with dominantly oxic conditions in the sediment deposition environment. The
higher atomic carbon nitrogen (C/N)a ratios and depleted stable carbon isotope ratio (δ13C) values for sediments from three study areas indicated the terrestrial sources of organic matter derived from C3 plant materials, whereas the contribution of organic materials from C4 vegetation and riverine productivity is low. Some silty sand samples exhibited lower (C/N)a ratios and enriched δ13C values in Sonargaon and Faridpur areas that are attributed to the adsorption of ammonium ions on clay minerals and the contribution
of organic matter from C4 plants. Total sulfur over total organic carbon (TS/TOC) ratios in sediments of the Ganges delta reflect the nonmarine environments
of sediment deposition. The lower ratios of syringyl to vanillyl phenols (S/V), cinnamyl to vanillyl phenols (C/V), and acid
to aldehyde in vanillyl phenols (Ad/Al)v observed in Daudkandi indicate that the lignin in sediments derived from dominant
woody gymnosperm sources and is very highly degraded. By contrast, the S/V ratio, C/V ratios, and [Ad/Al]v ratios in Faridpur
suggest that the lignin in sediments derived from a mixture of woody and nonwoody angiosperm plant tissue contribution that
underwent high degradation as well. 相似文献
999.
Moehninsi Kenji Miura Haruyuki Nakajyo Kosumi Yamada Koji Hasegawa Hideyuki Shigemori 《BMC plant biology》2010,10(1):111
Background
Raphanusanin (Ra) is a light-induced growth inhibitor involved in the inhibition of hypocotyl growth in response to unilateral blue-light illumination in radish seedlings. Knowledge of the roles of Ra still remains elusive. To understand the roles of Ra and its functional coupling to light signalling, we constructed the Ra-induced gene library using the Suppression Subtractive Hybridisation (SSH) technique and present a comparative investigation of gene regulation in radish seedlings in response to short-term Ra and blue-light exposure. 相似文献1000.