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T Shimano

Publications and source records attributed to T Shimano.

At least 73 records · Page 4Linked to original sources
PubMed1990

Relation between the weight of human tooth enamel and the CO3(3-) signal intensity on the ESR dosimetry.

Experiments were made to determine the dependence of CO3(3-) signal intensity on enamel weight in the ESR dosimetry utilizing teeth. After all human tooth enamel samples were crushed into 500-840 micrometers particles, they were irradiated with various doses of 60Co gamma rays at the same dose rate. Irradiated samples were distributed into 10-500 milli-grams weights and were measured with ESR instrument. The relation between CO3(3-) signal intensity and enamel weight have linearity up to 300 mg weight under the same dose as shown by measurements.

Cobalt Radioisotopes↗
PubMed1990

[A problem with ESR dosimetry utilizing human tooth enamel in low dose region].

Experiments were made to determine the dependence of CO3(3-) signal intensity on radiation dose in the low dose region from 3.1 x 10(-4) C/kg to 865.6 x 10(-4) C/kg. After all human tooth enamel samples were crushed into 350-500 micrometers particles, they were irradiated with 60Co gamma rays. Irradiated samples were measured with the ESR instrument, and the CO3(3-) signal appearance and the true signal have been determined. It is confirmed that the relation between the true intensity of the CO3(3-) signal and the exposure have linearity from 25.0 x 10(-4) C/kg to 865.6 x 10(-4) C/kg. It is difficult to confirm this in the case of less than 25.0 x 10(-4) C/kg due to the effect of organic signal and noise.

Cobalt Isotopes↗
PubMed1990

[Eccentric projection for the observation of the root canals of the upper premolars].

Information on the length and the shape of the root canals is necessary in dental care. They are obtained from X-ray examination of teeth. However, it is useful to apply eccentric projection for optimization in dental radiography. We observed 135 teeth and 355 films of extracted upper premolars, and tried to establish the standard of eccentric projection for the observation of root canals of the upper premolars, on the basis of the calculations and the experiments. 1. Shapes of root canals in the upper premolars are classified into 3 types with 3 subtypes. The rate of teeth with one root was 69.6%, but the rate of teeth with two root canals was 43%. These indicate the necessity of the eccentric projection in dental radiography, although there is a limit to the ability of X-ray film for confirmation of real condition of the root canals. 2. Optimal eccentric projection angle was 20 degrees-25 degrees. There is no significant difference between the paralleling technique and bisecting technique. There is no significant difference between the mesial and distal eccentric projection. But, the mesial eccentric projection is more effective for the observation of whole root and the ease of radiographic technique than the distal eccentric projection.

Bicuspid↗
PubMed1990

Malignant lymphoma of the rectum.

Eleven patients with primary lymphoma of the rectum were reviewed on a mainly histological basis, especially in association with reactive lymphoid hyperplasia (RLH). They included three males and eight females with an age range of 21-71 (median 59) years. Common symptoms were anal bleeding, melena, difficulty with defecation and constipation. A physical examination echogram and computed tomographic scans showed the tumor to be restricted to the rectum. The tumors were classified microscopically as six intermediate lymphocytic lymphomas (ILL) and five others. Histologic findings compatible with RLH were found in all five ILL cases and three of the others. Immunohistochemistry on paraffin-embedded sections revealed eight cases to be of B-cell type and one with a pleomorphic histology, to be of T-cell type; one case did not react with any of the antibodies tested, but were regarded as being of B-cell type purely on morphological grounds. A gene rearrangement study carried out in one ILL case showed a monoclonal rearrangement of the Jh chain. The findings showed rectal lymphoma to be characterized by a high frequency of ILL cases and an association with RLH. These are also common findings among patients with thyroid, salivary and gastric lymphoma, suggesting a common etiologic role in these diseases of long-standing inflammation.

Adult↗
PubMed1990

[The relation between serum carcinoembryonic antigen (CEA) and response to chemotherapy in patients with advanced colorectal cancer].

Prognostic factors from 22 cases of advanced colorectal carcinoma were examined with respect to age, the degree of cellular differentiation, pretreatment serum CEA and doubling time of circulating CEA. The prognoses were very poor for patients of younger age and poorly differentiated tumor. No correlations were observed between survival time and pretreatment serum CEA. A significant correlation of survival time and CEA doubling time was observed. The serial serum CEA levels were examined in the 11 colorectal cancer patients with unresectable multiple liver metastasis, who were treated with intraarterial selective chemotherapy. There were no significant differences between pretreatment serum CEA and survival time on response to chemotherapy. In 9 cases showing over 40 ng/ml of CEA before treatment, however, the serial change in CEA levels correlated well with response to chemotherapy. In four cases with recurrent liver metastasis, prolongation time could be predicted from the CEA induces with respect to the forward time earning and the alternation of the CEA doubling time. Furthermore, the two cases without any measurable lesions also showed the same trend. These results suggested that serial measurement of serum CEA were useful for monitoring the response to chemotherapy against advanced colorectal cancer when the pretreatment serum CEA was high (over 40 ng/ml).

Adenocarcinoma↗
PubMed1989

Human tooth dosimetry for gamma-rays and dental x-rays using ESR.

The effect of secondary electron equilibrium on the ESR dosimetry of x- and gamma-ray irradiation has been studied by using acrylic plates to simulate the soft tissue of the human mouth. Dental x-rays create a different ESR signal pattern at the front surface of the tooth vs the back surface. The effect on radiation build-up of the acrylic plate on gamma-irradiation is dominant at the front but is not appreciable at the back side of the tooth.

Cobalt Radioisotopes↗
PubMed1989

A human monoclonal antibody derived from axillary lymph nodes of a breast cancer patient.

A human hybridoma clone (A4-33) was established by fusion of human lymphoblastoid cells, HO-323, with lymphocytes of axillary lymph nodes obtained from a breast cancer patient. This clone has been stable, producing IgM for over 24 months. Enzyme-linked immunosorbent assay (ELISA) showed that monoclonal antibody A4-33 reacted strongly to MCF-7, and weakly to PANC-1 and HT-29, but not to other human malignant cell lines. The reactivity of A4-33 to MCF-7 was markedly reduced by treatment with periodate, but not affected or enhanced by neuraminidase or trypsin. Immunoperoxidase staining of normal human tissue sections showed that A4-33 reacted to acinar and ductal cells of the mammary gland and to ductal epithelial cells of the salivary gland, sweat gland, pancreas and bile duct. With malignant tumor sections, A4-33 reacted to breast cancer, pancreatic cancer and parotid cancer. These results suggested that A4-33 recognized the antigen which commonly exists on ductal epithelial cells of the exocrine gland.

Antibodies, Monoclonal↗
PubMed1988

Production of tumor necrosis factor (TNF) by monocytes from cancer patients and healthy subjects induced by OK-432 in vitro, and its augmentation by human interferon gamma.

A cytostatic factor was induced in the supernatants of human blood monocytes cultured in vitro with OK-432 at 0.01 KE/ml or more. This cytostatic activity was almost completely abolished by anti-human TNF antibody, and so was thought to be that of TNF. Recombinant human gamma interferon (IFN-gamma) alone did not induce TNF as described in other reports, but enhanced the induction of TNF by OK-432 when added to monocytes before or with OK-432. Monocytes of 20 patients with cancer of the digestive tract and 10 healthy donors were tested for ability to produce cytostatic activity. The frequencies of positive responses to OK-432 and the mean cytostatic activities of the two groups were similar. Moreover both groups included high responders whose monocytes produced potent cytostatic activity with OK-432 alone, and also low responders. Interestingly, marked synergistic effects of IFN-gamma and OK-432 were observed with monocytes that did not produce potent cytostatic activity with OK-432 alone. These results suggested that OK-432 may have a stronger immunomodulatory effect clinically when used in combination with IFN-gamma.

Biological Products↗
PubMed1987

Purification and characterization of a pancreas cancer-related antigen.

A pancreatic cancer-related antigen (PCRA) has been identified, isolated and characterized from liver metastases of pancreatic carcinoma. The purified PCRA was homogeneous by polyacrylamide disc gel electrophoresis, had an Mr of about 500,000, consisted of 30% carbohydrate and 70% protein, and migrated in the alpha 2-beta region in electrophoresis. In gel immunoprecipitation the antiserum against PCRA reacted with extracts of pancreatic cancer and spleen, but neither with normal human serum nor with normal pancreas, liver, lung, large and small intestine extracts. It clearly differed from other known pancreatic tumor-associated antigens.

Antigens, Neoplasm↗
PubMed1987

Tumor imaging with anti-CEA antibody labeled 19F emulsion.

The possibility of using 19F MRI for detection of tumors using a 2-T NMR system was examined in animals. Anticarcino-embryonic antigen (CEA) antibody conjugated with perfluorochemical (perfluorotributylamine, FTBA) was administered to nude mouse inoculated with LOVO, a CEA-producing human cancer cell line. Tumor imaging based on the 19F NMR was examined after excision of the tumors from nude mice (ex vivo). The imaging pattern of the tumor coincided with the antibody distribution determined immunohistologically.

Animals↗