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排序方式: 共有1891条查询结果,搜索用时 93 毫秒
191.
Takayuki Tomaru Shinji Miyoki Masatake Ohashi Kazuaki Kuroda Takashi Uchiyama Toshikazu Suzuki Akira Yamamoto Takakazu Shintomi Akitoshi Ueda Daisuke Tatsumi Shuichi Sato Koji Arai Masaki Ando Koji Watanabe Kenji Nakamura Masahiko Watanabe Kazuhiko Ito Izumi Kataoka Hiroaki Yamamoto Brett Bochner Yaron Hefetz 《Applied optics》2003,42(7):1306-1307
192.
Kazuma Nishimura Sayaka Hirai Hiroaki Kodama 《Journal of Bioscience and Bioengineering》2009,108(5):435-437
Small interfering RNAs (siRNAs) generated from the spacer region of hairpin RNAs were not detected in the RNA interference (RNAi) plants targeting the fatty acid desaturase gene. The expression of the desaturase gene was stably suppressed even when siRNAs targeting the spacer sequences were introduced into this plant. 相似文献
193.
Kanae Teramoto Wataru Kitagawa Hiroaki Sato Masaki Torimura Tomohiro Tamura Hiroaki Tao 《Journal of Bioscience and Bioengineering》2009,108(4):348-353
Rhodococcus erythropolis strains characterized as antibiotic producers can be classified into three groups according to their antibiotic spectrum and growth compatibility. Due to their high genotypic similarity, the taxonomic relationship of these strains has not been elucidated. In this study, ribosomal protein profiling using matrix-assisted laser desorption ionization-mass spectrometry (MALDI-MS) was employed to classify twenty-one strains of R. erythropolis (15 antibiotic producers and 6 non-antibiotic producers). In the first step in this method, a total of 30 intense peaks observed for purified ribosomal subunit proteins of the type strain (R. erythropolis JCM 3201T) were selected as the reference peaks. The mass spectra observed for the cell lysates of each sample strain were then checked as to whether peaks were observed at the same masses of the reference peaks. The results of peak matching were processed by cluster analysis, generating a dendrogram. Four major clusters of the R. erythropolis strains corresponded to three antibiotic groups and the non-antibiotic group. Furthermore, the topology of the dendrogram was highly comparable with the phylogenetic tree based on DNA gyrase subunit B gene (gyrB) sequencing. These results indicate that our proposed ribosomal protein profiling method using MALDI-MS is a potentially reliable and sufficiently high-throughput technique for the taxonomic analysis of closely related bacterial strains without using DNA sequence information. 相似文献
194.
195.
Plasma-deposited polycrystalline Si films [or microcrystalline Si (μc-Si) films] produced by plasma enhanced chemical vapor deposition (PECVD) have attracted considerable attention as novel, low-cost and stable materials for the photovoltaic i-layer in p–i–n junction thin-film solar cells. The μc-Si films prepared under various deposition conditions show widely various microstructures, from a crystalline–amorphous mixed state to an almost perfect crystalline state, with different crystallographic orientations. These structural changes directly influence the carrier transport properties that play a dominant role in determining photovoltaic performance. Furthermore, obtaining a uniform built-in electric field throughout the i-layer is a crucial issue for achieving excellent photovoltaic performance. To obtain a uniform electric field, the following terms should be required for the i-layer: ‘truly’ intrinsic characteristic (or not n-type characteristics) as well as structural uniformity in the growth direction without an incubation layer. Here, structural properties of μc-Si for achieving truly intrinsic characteristics are reviewed with an emphasis on collations with the crystalline volume function and the degree of (2 2 0) crystallographic preferential orientation in the crystalline phase. In addition, we reviewed a growth mechanism for the μc-Si film that is actually used in the photovoltaic i-layer in highly efficient solar cells: hybrid-phase growth consisting of conventional vapor-phase growth at the surface and the solid-phase crystallization that simultaneously occurs in the film. That growth is very effective in producing structural uniformity along the growth direction and for formation of crystallites directly on the underlying doped layer. 相似文献
196.
197.
198.
To improve the sensitivity or dynamic range of fibre-optic interferometer systems a new scheme utilising two optical loops is presented. The validity of the scheme is also experimentally confirmed by a tentative bulk-optic configuration 相似文献
199.
S Rondot KG Anthony S Dübel N Ida S Wiemann K Beyreuther LS Frost M Little F Breitling 《Canadian Metallurgical Quarterly》1998,279(3):589-603
Blue crabs mate immediately after the female's final moult. We tested the influence of female moult stage, sex ratio and male size on the pre-mating behaviour of both sexes, and the ability of males to pair with females and aggressively compete for access to females. We observed crabs in field enclosures and surveyed pre-copulatory mate-guarding patterns in the field. Female behaviour changed as they progressed through the final moult cycle, such that early moult-stage females avoided males, but late moult-stage females initiated pair formation. The changes in female behaviour influenced both the behaviour and pairing capability of males. Males courted and paired with late moult-stage females on their first attempt, but pursued early moult-stage females because their first attempts to pair often failed. In the field, early moult-stage females were paired less often than late moult-stage females. The pre-mating behaviour of both sexes also varied with sex ratio; when males were abundant, males traded courtship for forced capture and females courted less. Large males were more successful at take-overs, but did not pair more often with late moult-stage females, suggesting that large males do not consistently guard for less time than small males. The changes in female behaviour are consistent with the female's need to avoid the costs of guarding and suggest that females influence how pre-copulatory mate guarding occurs in this species.Copyright 1998 The Association for the Study of Animal Behaviour Copyright 1998 The Association for the Study of Animal Behaviour. 相似文献
200.
Masaki Okazaki Tosihiro Hamada Hiroaki Fujii Osamu Kusudo Akio Mizobe Shuji Matsuzawa 《应用聚合物科学杂志》1995,58(12):2243-2249
The activated sludge that had been sufficiently cultivated with DMF-containing waste water was entrapped and immobilized in spherical poly(vinyl alcohol) (PVA) hydrogel particles. Features of numbers and distribution of bacteria in the resultant PVA gel were estimated. The DMF-decomposing bacteria named Bacillus cereus D-1 was isolated. Several morphological and physiological responses of the bacteria were revealed. Spherical PVA gel with the DMF-decomposing bacteria prepared through of freezing and thawing was tested for treatment of DMF-containing effluent. Test results have shown the ability of stable operation and maintenance at the same capacity of 1 kg/m3/day by both a basic study and a bench plant test. © 1995 John Wiley & Sons, Inc. 相似文献