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81.
We evaluated the utility of a hybrid car in which both power sources of an electric motor and a gasoline engine are used and solar cells are settled on the roof and the bonnet. An array of 1.6 kW solar cells was installed on the top of a building to charge the batteries by solar energy. Though the capacities of the electric motor and batteries are half compared with conventional electric vehicles, we confirmed that this hybrid car has sufficient utility for practical use. The whole electric energy consumed in a day can be supplied by 1.6 kW solar cell system. 相似文献
82.
T. Yoshimitsu T. Kubota I. Nakatani T. Adachi H. Saito 《Microgravity science and technology》2002,13(4):3-13
For future exploration missions to small planetary bodies, in-situ surface observation by robots would be a promising method
to investigate the target body whose surface gravity is very small. The authors have researched the mobility system under
the microgravity environment and proposed a new mobile system which drives a robot by hopping. Due to the uncertainty of the
escape velocity from the target small body, the hop velocity of the robot has to be controlled on-board. This paper proposes
a velocity control method of the hopping mechanism, which was evaluated by microgravity experiments and compared with numerical
simulation analyses. 相似文献
83.
J Takita Y Hayashi T Nakajima J Adachi T Tanaka N Yamaguchi Y Ogawa R Hanada K Yamamoto J Yokota 《Canadian Metallurgical Quarterly》1998,17(24):3137-3143
We previously reported that loss of heterozygosity (LOH) on chromosome 9p21 correlates with poor prognosis of neuroblastoma and the p16 gene is not expressed in approximately two thirds of neuroblastoma cell lines. Here we demonstrated that p16 expression was induced by 5-aza-2-deoxycytidine treatment in cell lines with 5' CpG island methylation but not in cell lines without methylation. Furthermore, the cell cycle of neuroblastoma cell lines significantly delayed with accumulation of cells in G1 phase by transfection of a wild-type p16 expression vector. These results indicate that p16 is inactivated in part by DNA methylation and its expression is involved in the growth of neuroblastoma cells in vitro. To assess the biological and clinical significance of p16 expression in primary tumors, we undertook immunohistochemical analysis in 74 paraffin sections of neuroblastomas. p16 protein was undetectable in 45 of 74 cases (61%) and lack of p16 expression significantly correlated with poor prognosis of patients and advanced stage of the disease. There was no correlation between loss of p16 expression and N-myc amplification in these tumors. These results indicate that inactivation of the p16 gene is involved in the progression of neuroblastoma independently of N-myc amplification. 相似文献
84.
K Takei T Kohno K Hamada J Takita M Noguchi Y Matsuno S Hirohashi H Uezato J Yokota 《Canadian Metallurgical Quarterly》1998,58(16):3700-3705
The high incidence of loss of heterozygosity (LOH) on chromosome 18q in advanced non-small cell lung carcinomas indicates the presence of tumor suppressor gene(s) on this chromosome arm, which plays an important role in the acquisition of malignant phenotypes in lung cancers. In the present study, we examined 62 lung cancer specimens and 54 lung cancer cell lines for allelic imbalance at 11 microsatellite loci to define common regions of 18q deletions. Allelic imbalance of 18q was detected in 24 (55.8%) non-small cell lung carcinoma specimens and in 6 (31.6%) small cell lung carcinoma specimens, whereas a similar frequency of LOH was statistically inferred to occur in cell lines by analyzing marker homozygosity as an indirect measure of LOH. Five specimens and 11 cell lines showed partial or interstitial deletions of chromosome 18q, and 2 of them had homozygous deletions at the 18q21.1 region. A commonly deleted region was assigned between the D18S46 and y953G12R loci. The size of this region is less than 1 Mb, and the coding exons of three candidate tumor suppressor genes, Smad2, Smad4, and DCC, were mapped outside the region. This result suggests that the common region harbors a novel tumor suppressor gene involved in the progression of lung cancer. 相似文献
85.
A backfire mode zigzag antenna is analysed using the method of moments. The effects of the filament length of the zigzag on the -10 dB beam width is calculated. The zigzag antenna is applied to a symmetrical paraboloidal reflector antenna as a primary feed. The reflector antenna shows a relatively constant gain in the communication satellite frequency band 12.25-2.75 GHz.<> 相似文献
86.
An epidermoid tumor inside the Meckel's cave is rare. The symptoms caused by this tumor include trigeminal neuralgia, facial hypesthesia and paresis of the 3rd, 4th and 6th nerves. A case of epidermoid tumor inside Meckel's cave was presented. A 54-year-old female who had complained of 3rd nerve palsy with right facial hypesthesia since 3 years before was referred to our clinic. Magnetic resonance imaging (MRI) showed the tumor at Meckel's cave. The tumor removal was performed using the orbito-zygomatic approach. To avoid injury of the internal carotid artery and nerves inside the cavernous sinus, removal of the tumor inside the capsule was carried out leaving the capsule. Postoperatively, the tumor removal was confirmed by MRI and improvement of the 3rd and the 5th nerve palsy was obtained three months after surgery. This case suggests that the capsule of the tumor inside the Meckel's cave should be allowed to remain to avoid injury of the adjacent 4th, 5th and 6th nerves and of the internal carotid artery. 相似文献
87.
S Yokota H Kiyoi M Nakao T Iwai S Misawa T Okuda Y Sonoda T Abe K Kahsima Y Matsuo T Naoe 《Canadian Metallurgical Quarterly》1997,11(10):1605-1609
In this study, we examined a large number of patients to clarify the distribution and frequency of a recently described FLT3 tandem duplication among hematopoietic malignancies, including 112 acute myelocytic leukemia (AML), 55 acute lymphoblastic leukemia (ALL), 37 myelodysplastic syndrome (MDS), 20 chronic myelogenous leukemia (CML), 30 non-Hodgkin's lymphoma (NHL), 14 adult T cell leukemia, 15 chronic lymphocytic leukemia (CLL) and 38 multiple myeloma (MM). We also evaluated 71 cell lines derived from 11 AML, 31 ALL, two hairy cell leukemia, three acute unclassified leukemia, 10 CML, 12 NHL including six Burkitt's lymphoma, and two MM. Using genomic PCR of exon 11 coding for the juxtamembrane (JM) domain and first amino acids of the 5'-tyrosine kinase (TK) domain, this length mutation was found only in AML (22/112, 20%) and MDS (1/37). According to the FAB subclassification, they were 5/18 (28%) of M1, 4/29 (14%) of M2, 3/17 (18%) of M3, 6/24 (25%) of M4, 4/20 (20%) of M5 and 1/9 of refractory anemia with excess of blast in transformation. In the various cell lines examined, this abnormality was determined in only one derived from AML and never found in other hematological malignancies. The sequence analysis of the abnormal PCR products revealed that 23 of 24 showed internal tandem duplication with or without insertion of nucleotides. In one AML, insertion and deletion without duplication was determined. All 24 lengthened sequences were in-frame. Duplication takes place in the sequence coding for the JM domain and leaves the TK domain intact. In conclusion, we emphasize that the length mutation of FLT3 at JM/TK-I domains were restricted to AML and MDS. Since all these mutations resulted in in-frame, this abnormality might function for the proliferation of leukemic cells. 相似文献
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