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991.
Involvement of Two Plasmids in Fenitrothion Degradation by Burkholderia sp. Strain NF100 总被引:4,自引:0,他引:4 下载免费PDF全文
A bacterium capable of utilizing fenitrothion (O,O-dimethyl O-4-nitro-m-tolyl phosphorothioate) as a sole carbon source was isolated from fenitrothion-treated soil. This bacterium was characterized taxonomically as being a member of the genus Burkholderia and was designated strain NF100. NF100 first hydrolyzed an organophosphate bond of fenitrothion, forming 3-methyl-4-nitrophenol, which was further metabolized to methylhydroquinone. The ability to degrade fenitrothion was found to be encoded on two plasmids, pNF1 and pNF2. 相似文献
992.
The small spotted dogfish Scyliorhinus canicula and the blackmouth dogfish Galeus melastomus, whose depth distributions overlap in the upper part of the slope (c. 500 m depth), where they have access to the same prey community, have well‐developed eyes and a pure‐rod retina with a single layer of photoreceptors. Interspecific differences in rod outer segment length (LROS) within retinal regions were found. In the periphery and the retinal centre G. melastomus showed a LROS 24 and 30% longer, respectively, than S. canicula and, therefore, a potential for increased sensitivity. In both species longer LROS were always found in correspondence with the retinal centre where the ganglion cell topography formed a horizontal meridian that allowed for better discrimination of the horizon in the visual field. In this area LROS reached 53·4±4·1μm in S. canicula and 77·1±10·5μm in G. melastomus against 46·3±4·2μm and 61·1±10·1μm in the retinal periphery. No significant differences were recorded in LROS and rod density during growth. In both species, a rapid increase of theoretical visual acuity was found to be related to an increase in fish LT and lens size. Visual acuity ranged between 1·7 and 3 cycles degree‐1 in S. canicula and 2·4 and 4·2 in G. melastomus. The G. melastomus rod visual pigment showed the characteristic spectral adaptation to vision in deep‐water (λmax of 481 nm), but was also well placed to detect the bioluminescence of some of its main prey species. In S. canicula the visual pigment absorption (λmax of 496 nm) was more typical of shallow water living fishes. The opsin sequences of the two visual pigments are discussed and key amino acid sites were identified where sequence changes could be responsible for the spectral absorption differences between the two species. The possible relationship between LROS, visual acuity, visual pigment absorption, depth distribution and feeding behaviour are discussed. 相似文献
993.
Human recombinant IL-6/B cell stimulatory factor 2 augments murine antigen-specific antibody responses in vitro and in vivo 总被引:4,自引:0,他引:4
F Takatsuki A Okano C Suzuki R Chieda Y Takahara T Hirano T Kishimoto J Hamuro Y Akiyama 《Journal of immunology (Baltimore, Md. : 1950)》1988,141(9):3072-3077
The effects of human rIL-6/B cell stimulatory factor 2 (hrIL-6/BSF-2) from Escherichia coli on murine Ag, SRBC-specific antibody responses were examined in vitro and in vivo. HrBSF-2 was effective in augmenting the primary and the anamnestic plaque-forming cells response to SRBC in vitro. The augmentation of the primary response was apparent when B cell-enriched spleen cells (B cells) were cultured with BSF-2 in the presence of IL-2. On the other hand, hrBSF-2 alone strongly enhanced the anamnestic response in a dose-dependent manner when spleen cells from SRBC-immunized mice were used. These effects of BSF-2 were abolished completely by anti-BSF-2 antibody, but not by normal rabbit Ig. Cell depletion experiments indicated that L3T4 (CD4)+ T cells, but not Lyt-2(CD8)+ T cells, and adherent cells (macrophages) have an important role in this BSF-2-induced augmentation of the response. In addition, kinetic studies showed that hrBSF-2 acts on B cells in the anamnestic response even when added relatively late in the culture. Finally, it was determined whether BSF-2 also could be active in modulating antibody responses in vivo. BSF-2 was shown to enhance the primary and secondary antibody responses in mice. The most apparent effect of BSF-2 was observed in the secondary response. 相似文献
994.
In an attempt to determine whether mouse cytomegalovirus (MCMV) requires thymidine kinase (TK) for replication and whether it induces TK, TK-deficient mouse cells were isolated and used as host cells for MCMV. Mutant cells resistant to 200 μg/ml of 5-Bromodeoxyuridine (BUdR) were selected from SV40-transformed mouse cells, mks-A TU-7, by propagating the cells in the presence of varying concentrations of BUdR graded by serial 2-fold increments. The mutant cells, designated as TU-7 BU, showed a very low TK activity (less than 1/20 that of mks-A TU-7). Herpes simplex virus type 1 (HSV-1) replicated in starved as well as in unstarved TU-7 BU, whereas MCMV could replicate only in growing TU-7 BU and could not form plaques in monolayers of mks-A TU-7 or TU-7 BU. HSV-1 infection enhanced TK activity equally in both mks-A TU-7 and TU-7 BU. In contrast, TK activity of MCMV-infected mks-A TU-7 was lower than that of uninfected cells or cells inoculated with UV-inactivated virus. In addition, TK activity of the MCMV-infected TU-7 BU remained minimal without showing any increase. The replication of HSV-1 was completely inhibited in the presence of BUdR (10 μg/ml), whereas MCMV could replicate even in the presence of 50 μg/ml of BUdR. The results indicate that MCMV neither requires TK nor induces TK activity in the infected cells. 相似文献
995.
Summary The ultrastructural distribution of cholinesterase (ChE) activity was examined in the atrium of the guinea-pig heart using Karnovsky's method.The reaction products showing the ChE activity were found mainly in the neural elements in the atrium. There were axons showing no reaction products intermingled with axons showing the positive enzymatic activity. In the enzymatically positive axons, the reaction products were observed in the axon-Schwann interspace, the interspace between neighboring axons and the corresponding plasma membranes in nerve fiber bundles as well as preterminal axons. It was of interest to find that not only axons containing ordinary agranular vesicles, but also axons with larger granular vesicles showed the ChE activity.In terminals the enzymatic activity was found also in the axon-Schwann interspace, the interspace between the axolemma and the sarcolemma and the corresponding plasma membranes of the enzymatically positive areas. In the neuron the enzymatic activity was positive in the endoplasmic reticulum and the interspace between the neuronal plasma membrane and the corresponding plasma membrane of the satellite cell. Plasma membranes facing to these enzymatically positive spaces were also positive for the enzymatic activity.This investigation has been supported by a research fund from Takeda Chemical Industries, Ltd., Osaka, Japan.A part of this work has been presented at the 8th Annual Meeting of the Japan Society of Histochemistry and Cytochemistry held in Kyoto on Nov. 30–Dec. 1, 1967, and also at the 24th Annual Scientific Meeting of the Japanese Society of Electron Microscopy held in Kofu on May 11–12, 1968. 相似文献
996.
997.
Ken-ichi Hirano Tatsuya Tanaka Yoshihiko Ikeda Satoshi Yamaguchi Nobuhiro Zaima Kazuhiro Kobayashi Akira Suzuki Yasuhiko Sakata Yasushi Sakata Kunihisa Kobayashi Tatsushi Toda Norihide Fukushima Hatsue Ishibashi-Ueda Daniela Tavian Hironori Nagasaka Shu-Ping Hui Hitoshi Chiba Yoshiki Sawa Masatsugu Hori 《Biochemical and biophysical research communications》2014
998.
Kiyoshi Takahara Masaaki Ii Teruo Inamoto Kazumasa Komura Naokazu Ibuki Koichiro Minami Hirofumi Uehara Hajime Hirano Hayahito Nomi Satoshi Kiyama Michio Asahi Haruhito Azuma 《Biochemical and biophysical research communications》2014
Mesenchymal stem cells (MSCs) have generated a great deal of interest in the field of regenerative medicine. Adipose-derived stromal cells (AdSCs) are known to exhibit extensive proliferation potential and can undergo multilineage differentiation, sharing similar characteristics to bone marrow-derived MSCs. However, as the effect of AdSCs on tumor growth has not been studied sufficiently, we assessed the degree to which AdSCs affect the proliferation of prostate cancer (PCa) cell. Human AdSCs exerted an inhibitory effect on the proliferation of androgen-responsive (LNCaP) and androgen-nonresponsive (PC3) human PCa cells, while normal human dermal fibroblasts (NHDFs) did not, and in fact promoted PCa cell proliferation to a degree. Moreover, AdSCs induced apoptosis of LNCaP cells and PC3 cells, activating the caspase3/7 signaling pathway. cDNA microarray analysis suggested that AdSC-induced apoptosis in both LNCaP and PC3 cells was related to the TGF-β signaling pathway. Consistent with our in vitro observations, local transplantation of AdSCs delayed the growth of tumors derived from both LNCaP- and PC3-xenografts in immunodeficient mice. This is the first preclinical study to have directly demonstrated that AdSC-induced PCa cell apoptosis may occur via the TGF-β signaling pathway, irrespective of androgen-responsiveness. Since autologous AdSCs can be easily isolated from adipose tissue without any ethical concerns, we suggest that therapy with these cells could be a novel approach for patients with PCa. 相似文献
999.
选取广西、湖南等地野生葡萄,与经典酿酒葡萄比较,研究抗氧化活性和活性物质,同时监测葡萄酒发酵过程中各指标的动态变化,并对不同品种葡萄酒的抗菌性进行研究。结果表明:赤霞珠的酚类含量和抗氧化活性高于野生葡萄和玫瑰香葡萄,但野生葡萄酒的抗菌性能显著优于赤霞珠和玫瑰香葡萄酒。葡萄酒在发酵过程中其抗氧化活性和酚类物质含量均随发酵过程的进行而升高;总抗氧化活性与总酚含量、氧自由基清除能力与原花青素含量成显著正相关,相关系数均大于0.989;总花色苷含量在发酵初期上升,后期下降,葡萄酒颜色变浅。 相似文献
1000.
利用SSR分子标记技术,对中国不同生态棉区曾经或正在种植的主要来源于岱字棉、斯字棉、福字棉、乌干达棉的30个陆地棉主栽品种进行了DNA指纹分析。从1 803对SSR引物中筛选到重复性好、多态性丰富的20对核心引物。这些引物分属棉花15条染色体,共检测到116个等位基因,平均每对引物5.8个;PIC值范围为0.384~0.900,平均为0.716;MI值范围为1.152~9.000,平均为4.374。30个品种中有4个品种具有各自的特异引物,可将其与其它26个品种区分开,其它26个品种可利用至少2对引物组合进行区分。为更方便、准确地鉴定各品种,构建了30个品种20对核心引物的十进制数字指纹代码。该研究为陆地棉的品种鉴定和纯度检测、新品种权益保护以及标准DNA指纹库构建提供了重要依据。 相似文献