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K Kajihara

Publications and source records attributed to K Kajihara.

12 recordsLinked to original sources
PubMed2001

Physical disorder and optical properties in the vacuum ultraviolet region of amorphous SiO(2).

The optical absorption of point-defect-free SiO(2) glass in the vacuum ultraviolet region is primarily controlled by the concentrations of three- and four-membered ring structures composed of heavily strained Si-O-Si bonds. The main channel of color center formation by F(2) excimer laser (7.9 eV) irradiation is not Frenkel-defect generation of oxygen via two-photon absorption processes but a pair generation of E' and nonbridging oxygen hole centers by the one-photon excitation of these strained bonds with 7.9 eV photons.

Journal Article↗
PubMed2000

NTAKalpha and beta isoforms stimulate breast tumor cell growth by means of different receptor combinations.

Neural- and thymus-derived activator for ErbB kinases (NTAK) is a recently described member of the neuregulin family that binds directly to ErbB3 and ErbB4 and transactivates ErbB2. Rat NTAK has at least five alternative-spliced isoforms: alpha1, alpha2a, alpha2b, beta, and gamma. In order to understand their biological properties, this study focused on the NTAK alpha2a and beta isoforms, which have different EGF-like domains. The effect of these isoforms on cell growth and tyrosine phosphorylation in human breast cancer cells, MDA-MB-453 and T47D, was examined using the recombinant proteins. In terms of cell growth, NTAKalpha2a and NTAKbeta preferentially stimulate T47D cells and MDA-MB-453 cells, respectively, in a dose-dependent manner. Although both NTAKs induce the highest level of tyrosine phosphorylation of ErbB2, NTAKalpha2a and NTAKbeta preferentially induce ErbB3 and ErbB4 phosphorylation, respectively. Thus, NTAKalpha2a and NTAKbeta stimulate cell growth in different ways, by means of different combinations of receptors.

Alternative Splicing↗
PubMed1998

[A case of advanced gastric cancer with virchow's metastasis responding remarkably to combination chemotherapy of low-dose CDDP and 5-FU].

The patient was a 72-year-old female who had Stage IVb advanced gastric cancer with Virchow's and paraaortic lymph node metastases. She was considered nonresectable and placed on neoadjuvant chemotherapy consisting of low-dose CDDP and 5-FU. After 1 course of administration, Virchow's metastasis disappeared, and the tumor was remarkably reduced in size. However, this chemotherapy was interrupted by toxicity of grade 3 appetite loss, nausea and vomiting, so that total gastrectomy and splenectomy were performed, which were non-curative operation because of paraaortic lymph node metastases. Histopathological examination of the section of the primary tumor revealed that cancer cells had almost disappeared, and only a few atypical cells remained in the granulation tissue. Eleven months after the surgery, there has been no progression of Virchow's and paraaortic lymph node metastases. Combination chemotherapy of low-dose CDDP and 5-FU appears useful as an inductive approach to advanced gastric cancer.

Adenocarcinoma↗
PubMed1992

[Interhemispheric arachnoid cyst; report of three cases].

Three operated cases of the interhemispheric arachnoid cyst were reported. Case 1: a 58-year-old female suffering from progressive right hemi-rigidity and gait disturbance for the past two years. Case 2: a 66-year-old female was admitted with chronic headache. MRI demonstrated a large interhemispheric cyst in these two patients. Case 3: a 6-month-old male had frequent episodes of tonic seizure. MRI demonstrated interhemispheric cyst and agenesis of the anterior part of corpus callosum. The resection of the cystic wall via the interhemispheric approach was performed for all cases. General convulsive seizure developed in the early stage following operation in case 1 and case 2, in spite of routine administration of prophylactic anticonvulsant. The seizures were well controlled thereafter. In all cases, the cyst disappeared on the follow up CT. Simple resection of cyst wall is effective in the surgical treatment of interhemispheric arachnoid cysts.

Aged↗
PubMed1975

Dimethyl sulfoxide in central nervous system trauma.

Dimethyl sulfoxide has been tested in various experimental injuries of the central nervous system in relation to other therapies. It appears to be a useful drug in acute extradural mass-forming lesions, middle cerebral artery occlusion, respiratory anoxia, and spinal cord injuries, in rhesus and squirrel monkeys, dogs, and rats. The data from these studies suggest that in the experimental models used, DMSO is clearly superior to no treatment, and appears to be more generally effective than other comparable treatments. No satisfactory answer has yet been found to explain the beneficial effects of DMSO, but several hypothetical suggestions are offered; their validation hinges primarily on further confirmatory evidence. Further experiments with our present models and alternative research lines are discussed.

Animals↗