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排序方式: 共有91条查询结果,搜索用时 15 毫秒
1.
Sachi Oshima Shunichi Asai Naohiko Seki Chikashi Minemura Takashi Kinoshita Yusuke Goto Naoko Kikkawa Shogo Moriya Atsushi Kasamatsu Toyoyuki Hanazawa Katsuhiro Uzawa 《International journal of molecular sciences》2021,22(12)
We identified the microRNA (miRNA) expression signature of head and neck squamous cell carcinoma (HNSCC) tissues by RNA sequencing, in which 168 miRNAs were significantly upregulated, including both strands of the miR-31 duplex (miR-31-5p and miR-31-3p). The aims of this study were to identify networks of tumor suppressor genes regulated by miR-31-5p and miR-31-3p in HNSCC cells. Our functional assays showed that inhibition of miR-31-5p and miR-31-3p attenuated cancer cell malignant phenotypes (cell proliferation, migration, and invasion), suggesting that they had oncogenic potential in HNSCC cells. Our in silico analysis revealed 146 genes regulated by miR-31 in HNSCC cells. Among these targets, the low expression of seven genes (miR-31-5p targets: CACNB2 and IL34; miR-31-3p targets: CGNL1, CNTN3, GAS7, HOPX, and PBX1) was closely associated with poor prognosis in HNSCC. According to multivariate Cox regression analyses, the expression levels of five of those genes (CACNB2: p = 0.0189; IL34: p = 0.0425; CGNL1: p = 0.0014; CNTN3: p = 0.0304; and GAS7: p = 0.0412) were independent prognostic factors in patients with HNSCC. Our miRNA signature and miRNA-based approach will provide new insights into the molecular pathogenesis of HNSCC. 相似文献
2.
Deoxyribozymes (DNAzymes) having RNA-cleaving activity have widely been explored as tools for therapeutic and diagnostic purposes. Both the chemical cleaving step and the turnover step should be improved for enhancing overall activity of DNAzymes. We have shown that cationic copolymer enhanced DNAzyme activity by increasing turnover efficacy. In this paper, effects of the copolymer on DNAzymes modified with locked nucleic acids (LNA) or 2′-O-methylated (2′-OMe) nucleic acids were studied. The copolymer increased activity of these chemically modified DNAzymes. More than 30-fold enhancement in multiple-turnover catalytic activity was observed with 2′-OMe-modified DNAzyme in the presence of the copolymer. DNAzyme catalytic activity was successfully enhanced by cooperation of the added copolymer and chemical modification of DNAzyme. 相似文献
3.
采用非线性有限元方法,对循环荷载下圆柱和Ⅰ型钢筋混凝土剪力墙进行试验,通过能量消耗分析评估其损伤。首先,通过对荷载-位移关系、裂缝情况的研究以及经过分析所得的总应变能与试验加载能量的比较,验证分析方法的有效性。其次,对能量消耗分布以及钢筋和混凝土的配置进行研究。研究表明:能量消耗是评估剪力墙损伤的有效方法。 相似文献
4.
K. Sasajima K. Naoi T. Tsukada 《International Journal of Machine Tools and Manufacture》2001,41(13-14)
The truncation process as running-in wear was applied to evaluate surface asperity changes as removal at the top of its asperity profile. The measurement was done using an optical interferometric microscope. Whole surface profile was measured by the microscope supported by the stitching technique. The specimen was relocated on the microscope utilizing Hirth coupling as a hardware technique. Data obtained from a truncated specimen were precisely relocated to the original untruncated specimen by computer software in three dimensions. Then the profile change was obtained by deducting truncated data from the original data. The profile change was calculated as removed volume. The volume changes are plotted against a sliding length. As the software relocation technique needs the unchanged profile of a valley part, the evaluation is limited to where the truncation height is higher than −1.28 sigma (the standard deviation of untruncated original profile height). The present research can detect very little volume change that cannot be measured by other conventional methods, such as the gravimetric method. The advantages of the present method are as follows. It is possible to compare the truncated surface profile with the original untruncated surface profile in three dimensions. Thus, the inclination of the truncation surface can be evaluated and any other local changes can also be assessed. From this information the profiles of truncated surfaces will be linked to functions, and new parameters for truncation profile will be presented. 相似文献
5.
Marie-Paule Bassez Yoshinori Takano Naohiko Ohkouchi 《International journal of molecular sciences》2009,10(7):2986-2998
This article presents an experimental analysis of the organic content of two serpentinized peridotite rocks of the terrestrial upper mantle. The samples have been dredged on the floor of the Ashadze and Logatchev hydrothermal sites on the Mid-Atlantic Ridge. In this preliminary analysis, amino acids and long chain n-alkanes are identified. They are most probably of biological/microbial origin. Some peaks remain unidentified. 相似文献
6.
The relationships between morphology and proton conduction for Nafion membranes and hydrocarbon-type proton exchange membranes, namely, sulfonated poly(arylene ether ether ketone) (S-PEEK) and sulfonated poly(arylene ether sulfone) (S-PES), were investigated by small-angle X-ray scattering (SAXS) and atomic force microscopy (AFM). The direct simultaneous observation of surface morphology and active regions of proton conduction on membranes by combined high-resolution AFM phase imaging and an electrochemical technique at controlled humidity provided significant morphological information, particularly for the hydrocarbon-type membranes that exhibit few or no features on SAXS profiles. For the Nafion membranes, the active proton paths became denser and congregated with each other at over 60% RH, resulting in the formation of well-connected networks. For the hydrocarbon-type membranes, however, only the relatively small and dispersed proton paths were observed, which showed no significant change even as water content increased. We have demonstrated that the differences in microscopic morphology between the Nafion and hydrocarbon-type membranes are associated with the differences between their macroscopic proton conductivities. 相似文献
7.
N. Sasajima D. Lowe C. Bai Y. Yamada C. Ara 《International Journal of Thermophysics》2011,32(11-12):2696-2707
The Cr3C2?C peritectic fixed point was investigated to test its capability to serve as a practical high-temperature fixed point. An improved filling technique where C/C sheet works as a wick and graphite paper as a hopper was applied successfully, and the long-term stability of the peritectic cell was evaluated by means of radiation thermometry. The repeatability of the melting point in one day was 7 mK with a melting range of approximately 100 mK. The cell was aged for 7 days, and the evaluated 56 melting temperatures during this period all fall within 90 mK, with a standard deviation of 19 mK. X-ray transmission photos showed that the ingot was filled uniformly in the crucible. After the evaluation of long-term stability, no clear degradation of the ingot shape and no leakage of molten metal were observed. From these results, it can be concluded that the Cr3C2?C peritectic cell has good stability and robustness, and the new filling technique was established. The impurity effect on the Cr3C2?C peritectic cell was also investigated by adding tungsten powder to another cell as the impurity component. After the observation of melting and freezing plateaux, the cell was cut in half to analyze the microstructure by means of electron probe microanalysis (EPMA) and laser ablation inductively coupled plasma mass spectrometer (LA-ICP-MS). The high concentration of impurity was observed in the area of the chromium-rich domain (eutectic mixture of Cr7C3 and Cr3C2), which suggests that impurities were rejected from the Cr3C2 peritectic phase during the peritectic freezing and were accumulated in the Cr7C3?Cr3C2 eutectic phase. This explains why the impurity effect is more severe for the Cr7C3?Cr3C2 eutectic point than for the Cr3C2?C peritectic point. 相似文献
8.
Masahiro Ohshima Hiromu Ohno Iori Hashimoto Mikiro Sasajima Masayuki Maejima Keiichi Tsuto Tadaharu Ogawa 《Journal of Process Control》1995,5(1)
This paper describes the results of a joint university-industry study to control a fatty acid distillation sequence, which is plagued with severe disturbance problems. In order to solve the disturbance problem, a model predictive control algorithm is modified in terms of disturbance prediction. Assuming that the dynamics of the unmeasured disturbances is generated by an auto-regressive form, the dynamics of the disturbance can be adaptively identified by using time series data of prediction errors and inputs. Using an identified disturbance model with a process model, future outputs are predicted. Control actions are determined so that the predicted output is as close to the target value as possible. This modified model predictive control aglorithm is applied to a ratio control scheme for three distillation columns. The control system developed has been in use sucessfully for more than six years to produce commercial products. 相似文献
9.
K Mineura H Sasajima Y Itoh M Kowada N Tomura K Goto 《Canadian Metallurgical Quarterly》1998,39(2):189-192
A case is presented of a patient with bilateral retinoblastoma, treated at infancy with surgery, chemotherapy and radiotherapy, who subsequently developed at least four additional histologically distinct malignancies: a Ewing sarcoma of the left fibula, two extraskeletal osteosarcomas of the left lower extremity, a mucoepidermoid carcinoma of the right parotid gland and a squamous cell carcinoma of the left paranasal cavity. In addition to retinoblastoma, patients with a germline RB-1 mutation are at high risk of second primary malignancies. An additive carcinogenic effect of cytotoxic therapy in these patients has been assumed. Patients with hereditary retinoblastoma should be under life-long follow-up programmes including a regular head and neck examination for detection of new primaries, especially in the radiation field of the presenting retinoblastoma. 相似文献
10.
Shoichi Nasu Takaaki Tanifuji Katsuya Uchida Kenji Noda Toshimasa Kurasawa Tadashi Takahashi Masahiko Isshiki Takejiro Miyauchi Kohji Tanuma Fumio Sasajima 《Journal of Nuclear Materials》1980,91(1):121-126
The center temperature of Li2O pellets under neutron irradiation was measured using an encapsuled pin. The surface temperatures of the pellets and the pellet/cladding heat transfer coefficients were estimated on the basis of the well-known conductivity integral. 相似文献