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71.
The activity of Ca2+-dependent ATP pyrophosphohydrolase was found to fluctuate during spherule formation of the acellular slime mold Physarum polycephalum under starving incubation. The enzyme activity increased up to 16-fold at the 3rd day of the starvation, then decreased drastically to less than its original level. Column chromatography of the enzyme preparation suggested that the increase in the activity was due to de novo synthesis of a new isozyme. Cycloheximide inhibited the synthesis. The two isozymes were different in their Ca2+ sensitivity, the new one being less sensitive. 相似文献
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AMP deaminase [EC 3.5.6.4] purified from chicken erythrocytes was inhibited by phytic acid (inositol hexaphosphate), which is the principal organic phosphate in chicken red cells. Kinetic analysis has indicated that this inhibition is of an allosteric type. The estimated Ki value was within the normal range of phytic acid concentration, suggesting that this compound acts as a physiological effector. Divalent cations such as Ca2+ and Mg2+ were shown to affect AMP deaminase by potentiating inhibition by lower concentrations of phytic acid, and by relieving the inhibition at higher concentrations of phytic acid. These results suggests that Ca2+ and Mg2+ can modify the inhibition of AMP deaminase by phytic acid in chicken red cells. 相似文献
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Ohara Chisato Sekiguchi Atsushi Takakura Shu Endo Yuka Tamura Naho Kikuchi Hiroe Maruo Kazushi Sugawara Norio Hatano Kenji Kawanishi Hitomi Funaba Misako Sugawara Ayako Nohara Nobuhiro Kawai Keisuke Fukudo Shin Sudo Nobuyuki Cooper Zafra Yoshiuchi Kazuhiro Ando Tetsuya 《BioPsychoSocial medicine》2020,14(1):1-3
Although fatigue is a common and distressing symptom in cancer survivors, the mechanism of fatigue is not fully understood. Therefore, this study aims to investigate the relation between the fatigue and mindfulness of breast cancer survivors using anxiety, depression, pain, loneliness, and sleep disturbance as mediators. Path analysis was performed to examine direct and indirect associations between mindfulness and fatigue. Participants were breast cancer survivors who visited a breast surgery department at a university hospital in Japan for hormonal therapy or regular check-ups after treatment. The questionnaire measured cancer-related-fatigue, mindfulness, anxiety, depression, pain, loneliness, and sleep disturbance. Demographic and clinical characteristics were collected from medical records. Two-hundred and seventy-nine breast cancer survivors were registered, of which 259 answered the questionnaire. Ten respondents with incomplete questionnaire data were excluded, resulting in 249 participants for the analyses. Our final model fit the data well (goodness of fit index = .993; adjusted goodness of fit index = .966; comparative fit index = .999; root mean square error of approximation = .016). Mindfulness, anxiety, depression, pain, loneliness, and sleep disturbance were related to fatigue, and mindfulness had the most influence on fatigue (β = − .52). Mindfulness affected fatigue not only directly but also indirectly through anxiety, depression, pain, loneliness, and sleep disturbance. The study model helps to explain the process by which mindfulness affects fatigue. Our results suggest that mindfulness has both direct and indirect effects on the fatigue of breast cancer survivors and that mindfulness can be used to more effectively reduce their fatigue. It also suggests that health care professionals should be aware of factors such as anxiety, depression, pain, loneliness, and sleep disturbance in their care for fatigue of breast cancer survivors. This study was registered in the University Hospital Medical Information Network Clinical Trials Registry (UMIN number. 000027720) on June 12, 2017. 相似文献
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Qinlong Hao Mingjie Zheng Kechao Weng Yumei Hao Yao Zhou Yuchen Lin Feng Gao Ziqi Kou Shoji Kawamura Ke Yao Pinglong Xu Jinghai Chen Jian Zou 《遗传学报》2021,48(1):52-62
Although the unique organization of vertebrate cone mosaics was first described long ago,both their underlying molecular basis and physiological significance are largely unknown.Here,we demonstrate that Crumbs proteins,the key regulators of epithelial apical polarity,establish the planar cellular polarity of photoreceptors in zebrafish.Via heterophilic Crb2a-Crb2b interactions,the apicobasal polarity protein Crb2b restricts the asymmetric planar distribution of Crb2a in photoreceptors.The planar polarized Crumbs proteins thus balance intercellular adhesions and tension between photoreceptors,thereby stabilizing the geometric organization of cone mosaics.Notably,loss of Crb2b in zebrafish induces a nearsightedness-like phenotype in zebrafish accompanied by an elongated eye axis and impairs zebrafish visual perception for predation.These data reveal a detailed mechanism for cone mosaic homeostasis via previously undiscovered apical-planar polarity coordination and propose a pathogenic mechanism for nearsightedness. 相似文献
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Motosugi Nanane Nakamura Futoshi Nakajima Souta Takahata Chihiro Kawamura Kazuhiro Morimoto Junko 《Landscape and Ecological Engineering》2021,17(2):95-106
Landscape and Ecological Engineering - There have been many earlier studies of the biodiversity and ecosystem services of abandoned farmlands, but studies of abandoned villages are limited,... 相似文献
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