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排序方式: 共有827条查询结果,搜索用时 0 毫秒
821.
822.
The growth of Pseudomonas denitrificans ATCC 13867 under denitrifying conditions was significantly stimulated by adding an appropriate amount of formate (2.5 mM or above) to the growth medium. The accumulation of nitrite in the culture was markedly depressed so long as formate remained in the culture above a certain level. Cellular activities of enzymes participating in denitrification also changed. The cells grown in the presence of formate exhibited a lower nitrate reductase activity and, in contrast, a higher nitrite reductase activity than the cells grown without added formate. 相似文献
823.
Tetraneura nigriabdominalis (Sasaki, 1899) is a galling aphid that is distributed widely in Eurasia. In the present study, a diagnostic multiplex polymerase chain reaction (PCR) protocol was developed to discriminate two types of the cytochrome oxidase subunit I (COI) sequences in this species, and its usefulness was examined from 25 samples of T. nigriabdominalis. Multiplex PCR and electrophoresis revealed that 10 and 15 samples had one band of 133 bp (type A) and 426 bp (type B), respectively. This discrimination was identical to the division of the 25 samples based on the alignments of COI sequences (511 bp), indicating high accuracy of this protocol in distinguishing the two types. This protocol is useful for studying microgeographic distributions of the two types and genetic diversities in T. nigriabdominalis. 相似文献
824.
Hiroki Takakuwa Tetsu Yamashiro Mai Q. Le Lien S. Phuong Hiroichi Ozaki Ryota Tsunekuni Tatsufumi Usui Hiroshi Ito Tsuyoshi Yamaguchi Toshihiro Ito Toshiyuki Murase Etsuro Ono Koichi Otsuki 《Microbiology and immunology》2010,54(1):58-62
To estimate the prevalence of influenza A subtype H5N1 viruses among domestic ducks in the period between October and November 2006 when H5N1 outbreaks had been absent, 1106 healthy ducks raised in northern Vietnam were collected. Inoculation of all throat and cloacae samples into embryonated eggs resulted in the isolation of subtype H3N8 in 13 ducks, but not H5N1 viruses. Serological analyses demonstrated that five ducks (0.45%) solely developed H5N1 subtype-specific hemagglutinin-inhibiting and neuraminidase-inhibiting antibodies together with anti-non-structural protein 1 antibodies. The results suggested that the ducks were naturally infected with H5N1 viruses when obvious H5N1 outbreaks were absent. 相似文献
825.
Yukitaka Murakami Satoshi Shizukuishi Akira Tsunemitsu Kazuhisa Nakashima Yukio Kato Saburo Aimoto 《FEMS microbiology letters》1991,82(3):253-256
Porphyromonas gingivalis 381 cells were incubated with 125I-histidine-rich polypeptide (histatin) 5 in the presence or absence of unlabeled histatin 5, to evaluate the histatin-binding capacity of the cells. The binding of histatin 5 was rapid, reversible, saturable and specific. The number of histatin 5-binding sites per cell was 3,600, and the dissociation constant (Kd) was in the order of 10(-6) M. These findings suggest that histatin interacts with certain bacterial cells through specific binding sites on their surface, and will allow the development of a histatin radioreceptor assay. 相似文献
826.
Yuko Miyanaga Robert Shiurba Saburo Nagata Carl J. Pfeiffer Makoto Asashima 《Development genes and evolution》1998,207(7):417-426
A Xenopus-specific anti-leukocyte monoclonal antibody designated XL-2 was isolated and used to identify leukocytes in tailbud embryos
and activin A-treated explants of blastula animal cap. XL-2 bound to a 135-kDa polypeptide in western blots of protein extracts
from adult thymocytes, tailbud embryos, tadpoles, and explants. In cell suspensions, it immunostained the cell surface of
all types of adult leukocytes including lymphocytes, monocyte/macrophages, thrombocytes, and granulocytes. At embryonic stage
24, immunocytochemistry revealed XL-2-positive leukocytes, the earliest time at which such cells have been recognized. Whole-mount
staining of tailbud embryos and tadpoles showed a widely dispersed population of XL-2-reactive leukocytes, many of which had
elongated shapes and ameboid pseudopodia. In activin A-treated animal caps, XL-2 recognized a subpopulation of cells within
the lumen of the central fluid-filled cavity as well as cells in the interstitium of mesenchymal and mesothelial components
of the explant. Together, activin A and human interleukin-11 induced 100% of explants to form lumenal blood cells. Compared
to activin A alone, murine stem cell factor plus activin A significantly increased the numbers of XL-2-reactive leukocytes
and erythrocytes. These results support the view that activin A induces leukocyte and erythrocyte progenitors during Xenopus embryogenesis.
Received: 29 August 1997 / Accepted: 28 October 1997 相似文献
827.
Synthesis of a membrane protein with two transmembrane regions. 总被引:1,自引:0,他引:1
Takeshi Sato Toru Kawakami Kenichi Akaji Hiroki Konishi Koji Mochizuki Toshimichi Fujiwara Hideo Akutsu Saburo Aimoto 《Journal of peptide science》2002,8(4):172-180
A membrane protein with two transmembrane domains was synthesized by means of the thioester method. The F1F0 ATP synthase subunit c (Sub.c), which consists of 79 amino acid residues (MW 8257), was chosen as a target. For synthetic purposes, two building blocks, Boc-[Lys34(Boc)]-Sub.c(1-38)-SCH2CH2CO-Ala and Sub.c(39-79), were synthesized via solid-phase methods using Boc chemistry. RP-HPLC purification conditions for the transmembrane peptide were examined. As a result, a combination of a mixture of formic acid, 1-propanol and water with a phenyl column was found to be useful for separating the transmembrane peptide. The purified building blocks were condensed in DMSO in the presence of silver chloride, 3,4-dihydro-3-hydroxy-4-oxo-1,2,3-benzotriazine (HOOBt), N,N-diisopropylethylamine to give the product, Sub.c, after removal of Boc groups (yield 16%). The yield of the condensation reaction could be improved to 23% by raising the reaction temperature to 50 degrees C, and to 26% when a mixture of chloroform and methanol was used as a solvent. 相似文献