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51.
Takubo K Hirao A Ohmura M Azuma M Arai F Nagamatsu G Suda T 《Biochemical and biophysical research communications》2006,351(4):993-998
Lifelong spermatogenesis is maintained by coordinated sequential processes including self-renewal of stem cells, proliferation of spermatogonial cells, meiotic division, and spermiogenesis. It has been shown that ataxia telangiectasia-mutated (ATM) is required for meiotic division of the seminiferous tubules. Here, we show that, in addition to its role in meiosis, ATM has a pivotal role in premeiotic germ cell maintenance. ATM is activated in premeiotic spermatogonial cells and the Atm-null testis shows progressive degeneration. In Atm-null testicular cells, differing from bone marrow cells of Atm-null mice, reactive oxygen species-mediated p16(Ink4a) activation does not occur in Atm-null premeiotic germ cells, which suggests the involvement of different signaling pathways from bone marrow defects. Although Atm-null bone marrow undergoes p16(Ink4a)-mediated cellular senescence program, Atm-null premeiotic germ cells exhibited cell cycle arrest and apoptotic elimination of premeiotic germ cells, which is different from p16(Ink4a)-mediated senescence. 相似文献
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Ichiro Azuma Mikio Yamawaki Kosei Yasumoto Yuichi Yamamura 《Cancer immunology, immunotherapy : CII》1978,4(2):95-100
Summary The antitumor activity of the cell wall skeleton preparations of four species of Nocardia, N. brasiliensis strain 146, N. coeliaca strain 122, N. polychromogenes strain 6, and N. rubra, which showed potent adjuvant activity on the induction of cell-mediated cytotoxicity in allogeneic mice, was examined with the aid of EL-4 leukemia, melanoma B16, and MH-134 hepatoma in syngeneic mice. Preliminary clinical trials were performed and the results suggest that the cell wall skeleton of N. rubra, upon intrapleural injection, may be useful as an immunotherapeutic agent for patients with malignant pleurisy. The chemical properties of these cell wall skeleton preparations are described. 相似文献
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So Kato Yasushi Oshima Hiroyuki Oka Hirotaka Chikuda Yujiro Takeshita Kota Miyoshi Naohiro Kawamura Kazuhiro Masuda Junichi Kunogi Rentaro Okazaki Seiichi Azuma Nobuhiro Hara Sakae Tanaka Katsushi Takeshita 《PloS one》2015,10(4)
Objectives
The Japanese Orthopaedic Association (JOA) score is widely used to assess the severity of clinical symptoms in patients with cervical compressive myelopathy, particularly in East Asian countries. In contrast, modified versions of the JOA score are currently accepted as the standard tool for assessment in Western countries. The objective of the present study is to compare these scales and clarify their differences and interchangeability and verify their validity by comparing them to other outcome measures.Materials and Methods
Five institutions participated in this prospective multicenter observational study. The JOA and modified JOA (mJOA) proposed by Benzel were recorded preoperatively and at three months postoperatively in patients with cervical compressive myelopathy who underwent decompression surgery. Patient reported outcome (PRO) measures, including Japanese Orthopaedic Association Cervical Myelopathy Evaluation Questionnaire (JOACMEQ), the Short Form-12 (SF-12) and the Neck Disability Index (NDI), were also recorded. The preoperative JOA score and mJOA score were compared to each other and the PRO values. A Bland-Altman analysis was performed to investigate their limits of agreement.Results
A total of ninety-two patients were included. The correlation coefficient (Spearman’s rho) between the JOA and mJOA was 0.87. In contrast, the correlations between JOA/mJOA and the other PRO values were moderate (|rho| = 0.03 – 0.51). The correlation coefficient of the recovery rate between the JOA and mJOA was 0.75. The Bland-Altman analyses showed that limits of agreement were 3.6 to -1.2 for the total score, and 55.1% to -68.8% for the recovery rates.Conclusions
In the present study, the JOA score and the mJOA score showed good correlation with each other in terms of their total scores and recovery rates. Previous studies using the JOA can be interpreted based on the mJOA; however it is not ideal to use them interchangeably. The validity of both scores was demonstrated by comparing these values to the PRO values. 相似文献56.
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The stomach contents were analyzed monthly for each year-class to elucidate the foraging pattern of bluegills in a small vegetated lake by the frequency occurrence and the points methods. Seasonal dietary changes of the year-classes were considered comparing the monthly fluctuations in abundance of major prey organisms. Though these bluegills are dietary generalists and opportunists like those in North America, their foraging pattern was characterized by a relatively clearer dietary shift during ontogeny and a wider food niche including piscivorous than those of bluegills with congeners in their home land. Therefore this finding provides evidence of the ecological release caused by the absence of congeners. 相似文献
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Saito M Kato Y Ito E Fujimoto J Ishikawa K Doi A Kumazawa K Matsui A Takebe S Ishida T Azuma S Mochizuki H Kawamura Y Yanagisawa Y Honma R Imai J Ohbayashi H Goshima N Semba K Watanabe S 《FEBS letters》2012,586(12):1708-1714
Gene amplification is a major genetic alteration in human cancers. Amplicons, amplified genomic regions, are believed to contain "driver" genes responsible for tumorigenesis. However, the significance of co-amplified genes has not been extensively studied. We have established an integrated analysis system of amplicons using retrovirus-mediated gene transfer coupled with a human full-length cDNA set. Applying this system to 17q12-21 amplicon observed in breast cancer, we identified GRB7 as a context-dependent oncogene, which modulates the ERBB2 signaling pathway through enhanced phosphorylation of ERBB2 and Akt. Our work provides an insight into the biological significance of gene amplification in human cancers. 相似文献
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