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111.
Ishikawa  Junko  Fujimura  Shigeto  Kondo  Motohiko  Murai-Hatano  Mari  Goto  Akitoshi  Shinano  Takuro 《Plant and Soil》2018,424(1-2):503-524
Plant and Soil - In the Mediterranean basin, reduction in cloudiness owing to climate change is expected to enhance solar ultraviolet (UV) levels and to decrease rainfall over the coming years,...  相似文献   
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Vibrio cholerae O1 El Tor, the pathogen responsible for the current cholera pandemic, became pathogenic by acquiring virulent factors including Vibrio seventh pandemic islands (VSP)‐I and ?II. Diversity of VSP‐II is well recognized; however, studies addressing attachment sequence left (attL) sequences of VSP‐II are few. In this report, a wide variety of V. cholerae strains were analyzed for the structure and distribution of VSP‐II in relation to their attachment sequences. Of 188 V. cholerae strains analyzed, 81% (153/188) strains carried VSP‐II; of these, typical VSP‐II, and a short variant was found in 36% (55/153), and 63% (96/153), respectively. A novel VSP‐II was found in two V. cholerae non‐O1/non‐O139 strains. In addition to the typical 14‐bp attL, six new attL‐like sequences were identified. The 14‐bp attL was associated with VSP‐II in 91% (139/153), whereas the remaining six types were found in 9.2% (14/153) of V. cholerae strains. Of note, six distinct types of the attL‐like sequence were found in the seventh pandemic wave 1 strains; however, only one or two types were found in the wave 2 or 3 strains. Interestingly, 86% (24/28) of V. cholerae seventh pandemic strains harboring a 13‐bp attL‐like sequence were devoid of VSP‐II. Six novel genomic islands using two unique insertion sites to those of VSP‐II were identified in 11 V. cholerae strains in this study. Four of those shared similar gene clusters with VSP‐II, except integrase gene.
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MITOCHONDRIA IN LIVING CELLS: AN ANALYSIS OF MOVEMENTS   总被引:7,自引:4,他引:3       下载免费PDF全文
Time-lapse cinephotomicrography of mouse embryonic fibroblasts before and shortly after perfusion of tissue cultures reveals that the elongation of mitochondria caused by coenzyme A results from the terminal association of many shorter rods into a smaller number of long filaments. These are not permanent associations, but they reflect an exaggeration of the cohesive tendency of mitochondria, which in untreated cells is counterbalanced by frequent disjoinings and breakings of the anastomotic network. Our own observations and a survey of the literature suggest that elongate mitochondria with rapid movement and high metabolic activity tend to accompany proliferation in tissue cultures, and that mitotic inhibition of cultured cells may go together with short, slow mitochondria of low metabolic activity. The movement of mitochondria may be both active, reflecting metabolic exchanges with the cytoplasm, and passive, the result of hyaloplasmic currents.  相似文献   
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H Takemura  H Ohshika 《Life sciences》1999,64(17):1493-1500
Capacitative Ca2+ entry exists in rat glioma C6 cells; however, how the information of depletion of Ca2+ in intracellular stores transmits to the plasma membrane is unknown. In the present study, we examined whether Ca2+ influx factor (CIF) causes capacitative Ca2+ entry in C6 cells. CIF was extracted from non-treated (Non-CIF), bombesin-treated (BBS-CIF) and thapsigargin-treated (TG-CIF) C6 cells by a reverse-phase silica cartridge. The addition of BBS-CIF and TG-CIF gradually increased cytoplasmic Ca2+ concentration ([Ca2+]i) but Non-CIF did not increase [Ca2+]i. Neither BBS-CIF nor TG-CIF elevated [Ca2+]i in the absence of extracellular Ca2+. Gd3+ inhibited the increase in [Ca2+]i induced by BBS-CIF and TG-CIF. Genistein abolished an elevation of [Ca2+]i induced by BBS-CIF and TG-CIF. BBS-CIF and TG-CIF did not increase inositol 1,4,5-trisphosphate accumulation. The results suggest that capacitative Ca2+ entry is caused by CIF in rat glioma C6 cells.  相似文献   
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A series of novel 6-desfluoro [des-F(6)] and 6-fluoro-1-[(1R,2S)-2-fluorocyclopropan-1-yl]-8-methoxyquinolones bearing 3-(1-aminocycloalkyl)pyrrolidin-1-yl substituents at the C-7 position (1–6) was synthesized to obtain potent drugs for nosocomial infections caused by Gram-positive pathogens. The des-F(6) compounds 4–6 exhibited at least four times more potent activity against representative Gram-positive bacteria than ciprofloxacin or moxifloxacin. Among the derivatives, 7-[(3R)-3-(1-aminocyclopropan-1-yl)pyrrolidin-1-yl] derivative 4, which showed favorable profiles in preliminary toxicological and non-clinical pharmacokinetic studies, exhibited potent antibacterial activity against clinically isolated Gram-positive pathogens that had become resistant to one or more antibiotics.  相似文献   
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