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91.
Effect of ascorbic acid on fibrinolysis 总被引:1,自引:0,他引:1
M Shimizu Y Hatta H Hayashi M Itokawa Y Yanagisawa 《Journal of Japan Haematological Society》1970,33(1):137-148
92.
Relationship between production of epidermal growth factor receptors, gene amplification, and chromosome 7 translocation in variant A431 cells 总被引:1,自引:0,他引:1
G N Gill W Weber D M Thompson C Lin R M Evans M G Rosenfeld S Gamou N Shimizu 《Somatic Cell and Molecular Genetics》1985,11(4):309-318
Synthesis of the epidermal growth factor (EGF) receptor has been analyzed in a series of variant A431 human epidermoid carcinoma cell clones reported to contain different amounts of EGF binding sites. The amount of EGF receptor protein, quantitated by immunoaffinity chromatography, and EGF receptor mRNA, quantitated by cDNA hybridization, were closely correlated to the extent of EGF receptor gene amplification. This correlation existed in variants selected for reduced EGF receptors and in revertants from those variants with increased EGF receptors. There was also a correlation between the frequency of translocation of chromosome 7, containing the EGF receptor gene, and EGF receptor protein. These results support gene amplification as the mechanism enhancing A431 cell EGF receptor protein and determining growth responses. 相似文献
93.
94.
Yoshida C Suzukawa K Katsura Y Shimizu S Mukai HY Hasegawa Y Imagawa S Kojima H Nagasawa T 《Cancer Genetics and Cytogenetics》2004,150(1):62-65
We describe the case of a 40-year-old man whose disease was initially diagnosed as acute myelocytic leukemia. The patient achieved remission with chemotherapy, but relapsed shortly afterwards with an acute T-cell lymphoblastic leukemia. He died of intracranial bleeding. Karyotyping analysis showed a del(9p?) as a common abnormality in the leukemic cells at onset and relapse. Fluorescence in situ hybridization analysis demonstrated allelic loss of the CDKN2A gene in cells from both stages of the disease. At relapse the leukemia cells had additional abnormalities such as add(1)(p36) and del(12)(p11). We postulate that the loss of CDKN2A is involved in leukemogenesis but does not determine the lineage of the leukemic cells. Instead, abnormalities of genes at 1p36, 12p11, or both may be involved in driving a lymphoid phenotype. 相似文献
95.
Kurata H Shimizu N Misumi K 《Genome informatics. International Conference on Genome Informatics》2004,15(2):161-170
A goal of systems biology is to build a concrete biochemical network map, which provides an important instruction to trace the pathways of interest or to understand the mechanism of a biological system. In the postgenomic era, not only the concrete biochemical maps, but also postgenomic maps (mRNA coexpression and protein-protein interaction networks) have been extensively produced. In the biochemical map, the individual reactions are reliable, but the number of the reactions is limited, because molecular biology requires extensive experiments to verify them. By contrast, postgenomic data provide much information regarding interactions, but are coarse-grained. To expand the biochemical network, an intuitional approach, which superposes postgenomic data on the map one by one, has been carried out, but it is not effective when a large amount of the coarse-grained data is handled. In order to effectively integrate such postgenomic interactions into a biochemical map, a statistical approach would be suitable rather than intuition. In this article, we proposed a novel statistical approach that integrates postgenomic interaction networks into the biochemical network, predicting novel pathways. A statistical correlation for such different types of networks identifies functional modules; subsequently the superposition of the different networks on the functional modules predicts inter-modular relations, which are the key pathways to construct a large-scale biochemical network. 相似文献
96.
Kanamycin ototoxicity in glutamate transporter knockout mice 总被引:2,自引:0,他引:2
Glutamate-aspartate transporter (GLAST), a powerful glutamate uptake system, removes released glutamate from the synaptic cleft and facilitates the re-use of glutamate as a neurotransmitter recycling system. Aminoglycoside-induced hearing loss is mediated via a glutamate excitotoxic process. We investigated the effect of aminoglycoside ototoxicity in GLAST knockout mice using the recorded auditory brainstem response (ABR) and number of hair cells in the cochlea. Kanamycin (100 mg/mL) was injected directly into the posterior semicircular canal of mice. Before the kanamycin treatment, there was no difference in the ABR threshold average between the wild-type and knockout mice. Kanamycin injection aggravated the ABR threshold in the GLAST knockout mice compared with the wild-type mice, and the IHC degeneration was more severe in the GLAST knockout mice. These findings suggest that GLAST plays an important role in preventing the degeneration of inner hair cells in aminoglycoside ototoxicity. 相似文献
97.
A novel STK11 germline mutation in two siblings with Peutz-Jeghers syndrome complicated by primary gastric cancer 总被引:1,自引:0,他引:1
Shinmura K Goto M Tao H Shimizu S Otsuki Y Kobayashi H Ushida S Suzuki K Tsuneyoshi T Sugimura H 《Clinical genetics》2005,67(1):81-86
Patients with Peutz-Jeghers syndrome (PJS) are known to be at risk of gastric cancer (GC), and the STK11 gene is a susceptibility gene for PJS. However, as no cases of PJS with GC in which a STK11 germline mutation has been identified have ever been reported and other susceptibility genes have also been suggested to be involved in PJS, the relation between STK11 germline mutations and GC in PJS is still unknown. In this study, we used sequencing analysis to investigate the STK11, CDH1, and TP53 loci for a germline mutation in two siblings with PJS with primary GC. A novel type of the STK11 germline mutation, c.890delG, encoding a truncated protein (p.Arg297fsX38) was identified, but no germline mutations of the CDH1 and TP53 genes were detected. No inactivation of the wild-type allele by somatic mutation or chromosomal deletion or hypermethylation at the 5'-CpG site of STK11 was detected in the GC. This is the first report of a STK11 germline mutation in a PJS patient with GC and should contribute to establishing correlations between the STK11 germline mutations and GC in PJS patients. 相似文献
98.
Possible contribution of follicular interleukin-1beta to nitric oxide generation in human pre-ovulatory follicles 总被引:2,自引:0,他引:2
Tao M; Kodama H; Kagabu S; Fukuda J; Murata M; Shimizu Y; Hirano H; Tanaka T 《Human reproduction (Oxford, England)》1997,12(10):2220-2225
The aim of this study was to investigate the relationships between
follicular nitric oxide (NO) metabolite concentrations and several related
variables, with special reference to follicular interleukin- 1beta
(IL-1beta). The follicular fluid from the leading and secondary follicles
was collected individually from 20 women undergoing in-vitro fertilization
(IVF) treatment, and the concentrations of nitrite (NO2-) and nitrate
(NO3-) were determined fluorometrically using 2,3- diaminonaphthalene. Both
follicular nitrite (r = 0.42, P < 0.01) and nitrate (r = 0.49, P <
0.001) were found to be significantly correlated with follicular IL-1beta
concentrations. There were also significant positive correlations between
follicular nitrate and the number of oocytes retrieved (P < 0.01) and
serum oestradiol concentration on the day of human chorionic gonadotrophin
(HCG) administration (P < 0.05). When follicular cells were incubated in
vitro with 10 ng/ml of IL-1beta for 24 h, nitrate generation was
significantly (P < 0.01) elevated compared with the control. In
conclusion, our study demonstrates that follicular IL-1beta and the number
of developing follicles are significant variables that affect follicular NO
concentrations, and points to the possible contribution of IL-1beta to NO
generation in human preovulatory follicles.
相似文献
99.
This theoretical study explored whether the directions of loads to which modern human molars are commonly subjected to are reflected in the biomechanical behavior of the tissue itself. A detailed finite element model of a piece of decussating enamel (M3 paracone) was created, taking into account differences in crystal orientation between the prism head and the interprismatic matrix, and was tested under differently angled mediolateral loads (i.e., mimicking various stages of the chewing cycle). Second, although teeth are highly mineralized, they also contain organic material and water, while in modern humans, there are systematic differences in chemical composition from the outer enamel surface to the dentinoenamel junction. To test the biomechanical effects of this gradient in mineralization a second set of models with gradually changing properties was created and subjected to the same loads. Chemically heterogeneous enamel yielded overall lower stress levels than homogenous enamel, especially at extreme loading angles. However, the general trends regarding the increase in tensile stresses at more oblique angles, and the number of nodes exhibiting tension, were comparable between the different set‐ups. The findings support suggestions that (a) the biomechanical behavior of dental tissue is the combined result of micromorphology and chemical composition and (b) that the range of loading directions, to which teeth are normally subjected to, can be inferred from dental microanatomy. For (palaeo)biological applications, the findings suggest that the absolute strength of teeth (e.g., bite force) cannot be predicted with certainty, whereas kinematic parameters of the masticatory apparatus can. Anat Rec, 2007. © 2008 Wiley‐Liss, Inc. 相似文献
100.
Toshio Takeuchi Hiroshi Iwasaki Yuko Ohjimi Yasuhiko Kaneko Masako Ishiguro Chikako Fujita Yasusi Mlura Yoshiharu Hiratsuka Kimitaka Sakamoto Masahiro Kikuchi 《Pathology international》1996,46(4):292-297
The cytogenetic and morphologic characteristics of a case with a primitive neuroectodermal tumor (PNET) arising from the left kidney in a 22 year old man are presented. The patient was detected as having a left renal mass with a tumor embolus In the inferior vena cava and multiple pulmonary metastases. A radical nephrectomy with tumor embolectomy of the Inferior vena cava, along with a resection of the pulmonary nodules were performed. Histologic examination revealed a dense proliferation of small round cells with many Homer-Wright type rosettes and perlvascular pseudo-rosettes. Immunohlstochemically, the tumor cells stained strongly positive for HBA71(p30/32M IC2 ), a surface glycopro-teln specific to PNET and Ewlng's sarcoma. In addition, the tumor cells expressed several neural markers (neuron specific enolase, neurofilament, synaptophysin, and Leu-7) and vimentin, while the epithelial, muscular, and lymphocytlc markers were negative in the tumor cells. Cytogenetic analysis of cultured tumor cells showed a reciprocal translocation t(11; 22)(q24; q12) that is considered to be specific to PNET and Ewing's sarcoma. In conclusion, this case suggested that a karyotyping analysis is a useful diagnostic tool for renal PNET, and it may therefore be utilized to help distinguish between difficult cases of small round cell tumors and Wilms' tumor of the kidney. 相似文献