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101.
Nitric oxide synthase [EC 1.14.23] from the particulate fraction of rat cerebella was purified and characterized. The homogenate of rat cerebella was centrifuged to obtain a pellet, which was washed and incubated with Triton X-100 containing buffer. The enzyme activity appeared in the 100,000 x g supernatant after incubation with the detergent. The solubilized enzyme was then purified by sequential affinity chromatography using adenosine 2',5'-diphosphate agarose and calmodulin Sepharose 4B, which gave a product that migrated as a single protein band on SDS/PAGE with a molecular mass of about 150 kDa. The purified enzyme exhibited an absolute requirement for FAD, in addition to NADPH and Ca2+/calmodulin. Thus, there is an insoluble nitric oxide synthase in rat cerebellum that has similar characteristics to the soluble type.  相似文献   
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T Koyama  F Harada    S Kawai 《Journal of virology》1984,51(1):154-162
The accompanying paper (S. Kawai and T. Koyama , J. Virol. 51:147-153, 1984) describes the isolation and biological properties of a mutant, TK15 , derived from a Rous sarcoma virus mutant, tsNY68 . The cis-acting defect of the mutant is analyzed biochemically in this paper. TK15 virions released from virus-producing 15c (+) cells were deficient in viral genomic 39S RNA, although comparable amounts of viral RNAs were transcribed in 15c (+) and tsNY68 -infected cells. Analysis of provirus DNA occurring in 15c (+) cells suggested that the mutant genome had a deletion of ca. 250 bases near the 5' end of the genome somewhere between the primer binding site and the 5' end of the gag-coding region. These findings indicate that at least part of the sequence lost in the TK15 genome is indispensable for packaging viral genomic RNA into virions. TK15 induces nonvirus -producing 15c (-) transformants at high frequency. Southern blot analysis of DNAs from those 15c (-) clone cells revealed that TK15 -derived proviruses contained various extents of internal deletions. Many 15c (-) clones had a provirus carrying only the src gene with long terminal repeat sequences at both ends. The mechanism for the segregation of 15c (-) cells is discussed.  相似文献   
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We attempted to optimize sulfonamide-based non-alkyne LpxC inhibitors by focusing on improvements in enzyme inhibitory and antibacterial activity. It was discovered that inhibitors possessing 2-aryl benzofuran as a hydrophobe exhibited good activity. In particular, compound 21 displayed impressive antibacterial activity (E. coli MIC = 0.063 μg/mL, K. pneumoniae MIC = 0.5 μg/mL, and P. aeruginosa MIC = 0.5 μg/mL), and is a promising lead for further exploration as an antibacterial agent.  相似文献   
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Three kinds of nuclease preparations, each of which having both endonuclease activity that formed 5′-mononucleotides and 3′-nucleotidase activity, were separated and partially purified from Shii-take, Lentinus edodes. Both enzyme activities of each preparation showed a similar thermostability and electrophoretic mobility on Polyacrylamide gel, and a competitive relationship was observed between RNA and 3′-AMP in their enzyme reactions. From these results, it is concluded that both enzyme activities of these three preparations reside in a single protein, respectively. They resemble one another in substrate specificity, cleavage pattern of RNA and thermostability, but are distinguishable from one another by molecular weight, electrophoretic mobility and optimum pH for degradation of RNA.  相似文献   
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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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Limnology - The purpose of this study was to estimate the genetic distance, diversity and relationship of two large groups of Malawian cichlid, ‘mbuna’ living in rocky area and feeding...  相似文献   
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