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561.
MYC is a major oncogene that plays an important role in cell proliferation in human cancers. Therefore, the mechanism behind MYC regulation is a viable therapeutic target for the treatment of cancer. Comprehensive and efficient screening of MYC regulators is needed, and we had previously established a promoter screening system using fluorescent proteins and the CRISPR library. For the efficient identification of candidate genes, a database was used, for which mRNA expression was correlated with MYC using datasets featuring “Similar” and “Not exactly similar” contexts. INTS14 and ERI2 were identified using datasets featuring the “Similar” context group, and INTS14 and ERI2 were capable of enhancing MYC promoter activity. In further database analysis of human cancers, a higher expression of MYC mRNA was observed in the INTS14 mRNA high-expressing prostate and liver cancers. The knockdown of INTS14 in prostate cell lines resulted in decreased MYC mRNA and protein expression and also induced G0/1 arrest. This study confirmed that CRISPR screening combined with context-matched database screening is effective in identifying genes that regulate the MYC promoter. This method can be applied to other genes and is expected to be useful in identifying the regulators of other proto-oncogenes.  相似文献   
562.
A series of uniaxially drawn films of isotactic polypropene and ethene-propene random copolymer was prepared. The differences in the crystal orientation between the bulk and the surface layer were examined using wide-angle X-ray diffraction and grazing incidence X-ray diffraction techniques. It was found that the c-axis orientation of the surface layer is almost identical with that of the bulk. The magnitude in the b-axis of the polypropene films decreased with increasing draw ratio. The changes in the b-axis at the bulk were found to be greater than those at the surface layer.  相似文献   
563.
Tumour metastasis in BCG-pretreated mice was studied using a methylcholanthrene-induced fibrosarcoma in C3H/He mice. When tumour cells were injected into the BCG-primed site, distant metastasis occurred in the lungs and the popliteal lymph node, through this tumour did not metastasize in normal mice. Such metastases were increased in proportion to the number of tumour cells injected into the BCG-primed site, and developed soon after tumour challenge. Concomitant immunity developed well in the mice bearing such metastases, but did not inhibit metastatic growth. Experiments using 125I-labelled SRBC or tumour cells revealed that such cells egressed rapidly from the BCG-primed site. When the tumour was inoculated into the contralateral foot to the BCG-primed site, the incidence and the number of metastases was reduced. Furthermore, BCG infection induced an increase of platelet count. I.v. injection of this tumour induced marked thrombocytopenia in normal mice. Administration of pentoxifylline, a methylxanthine derivative before tumour challenge reduced such metastases. These findings suggest that the changes in peripheral blood, such as increased platelet count and increased release of tumour cells from the injection site, facilitated distant metastasis in BCG-pretreated mice.  相似文献   
564.
565.
To reduce energy consumption, it is important to increase the efficiency of gears used for power transmission. In the present work, the efficiencies of gear drives with standard and profile shifted involute gears are measured by changing the type of lubricating oil. A new equation for calculating efficiency is derived by taking into account the additional friction torque that depends on the shape of the teeth. The efficiencies calculated with the new equation agree well with those obtained by experiments conducted using two planetary gear drives with different tooth shapes and with different reduction ratios (u = 4. 89 and 151). The new equation is applicable to the design of gear drives with higher efficiency.  相似文献   
566.
In this letter, the customer profit‐maximization‐model is expanded to incorporate the probabilistic profit of reserve supply. This extended model will change the customer behavior and therefore will affect the system performance. The analysis of the extended model is carried out to show how this model, considering energy and reserve market parameters, affects the customer decision. © 2012 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.  相似文献   
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