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The malignant schwannoma cell line (HKMS) was established from the subcutaneous tumor of Axilla region of a 48-year-old Japanese woman. The HKMS line has the following biological properties. 1. The HKMS cells were spindle in shape and showed neoplastic and pleomorphic features. The monolayer sheet of HKMS cells showed the resemble cell-arrangement with that of the original tumor tissue. 2. The cells showed a stable growth and the serial passages were successively carried out 150 times within 3 years. Their population doubling time is about 40 hours. 3. The chromosome number varied widely, and the modal number was stable at the 78-80. The marker chromosomes were present. 4. The cells were transplanted into the subcutis of nude mice and produced the malignant schwannoma.  相似文献   
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We cultured an aspiration fluid of the sternal bone marrow of the patient having adrenal neuroblastoma and established a neuroblastoma cell line (HSNB). The HSNB line has the following biological properties. 1. They are small round in shape and proliferate in flotation while forming cell aggregate, and often they attach the bottom of plastic dish and process the nerve-like fibers. A rough-endoplasmic reticulum are poorly developed, however, a lot of free ribosomes are scattered in the cytoplasm. In the peripheral area of the cells, small spherical secretory granules (60-140 nm in diameter) are existed. One characteristic of this cell is existence of microtubules in the cell-projections. 2. They show a stable growth and the doubling time is about 50 hours. 3. Their chromosome number varied widely and the mode is 46. The double minute chromosomes were present in 50% of cells. 4. When they are transplanted in the cheek pouch of hamster, they produced the neuroblastoma. 5. They produce neuron specific enolase. 6. N-myc gene was amplified ca 250 folds.  相似文献   
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The reaction to C-banding was investigated throughout the mitotic cycle ofCrepis capillaris (2n=6): (1) 18–22 C-bodies or C-bands were found during mid telophase and interphase to prophase and metaphase, and also 12–14 at late anaphase to early telophase in the mitotic cycle. Fewer C-bands in late anaphase to early telophase were due to the absence of minute bands; (2) large and medium sized C-bands were strongly stained by Giemsa, while small and minute bands stained palely. It is suggested that inCrepis capillaris the difference of color in C-banded segments following Giemsa staining is referable to the amount of constitutive heterochromatin rather than to the difference in the condensation and decondensation; (3) the size of C-bodies changed during telophase to interphase and prophase. It is inferred that the extent of C-bodies is regulated by both the length of DNA sequences of constitutive heterochromatin and the amount of proteins combined with C-banded DNA. It was shown that the reaction to C-banding is neither due to the differential condensation of chromatin nor to a higher concentration of DNA in the C-banded regions, in the C-banding mechanism as has been suggested so far at least.  相似文献   
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A low-molecular-mass protein, tentatively named meleagrin, was isolated from a commercial preparation of turkey (Meleagris gallopavo) ovomucoid. This 40-amino acid protein contains 3 disulfide bonds and high concentrations of aromatic residues (2 tryptophans and 3 tyrosines). It lacks threonine, methionine, phenylalanine, and arginine residues. The complete amino acid sequence was determined to be the following: less than Glu-Val-Leu-Lys-Tyr-Cys-Pro-Lys-Ile-Gly-Tyr-Cys-Ser-Ser-Lys-Cys-Ser-Lys- Ala- Glu-Val-Trp-Ala-Tyr-Ser-Pro-Asp-Cys-Lys-Val-His-Cys-Cys-Val-Pro-Ala-Asn- Gln-Lys - Trp. One of the three disulfide bonds exists between Cys12 and Cys28, and the two others links Cys32-Cys33 with Cys6 and Cys16. The amino acid sequence of meleagrin shows a strong homology to a similar basic protein, cygnin (Simpson, G.R. & Morgan, F.J. [1983] Int. J. Pep. Protein Res. 22, 476-481), of a rather distantly related aves, black swan (Cygnus atratus), suggesting some vital role of this protein in avian eggs. Similarity to a part (exon 9) of transferrins was also recognized.  相似文献   
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The mAb R18-9 recognizes a cross-reacting idiotope outside the Ag-combining site of the syngeneic anti HLA-DQw3 mAb KS13, whereas the mAb R1-38, KO3-34, KO3-256, and KO3-335 recognize spatially close private idiotopes within the Ag-combining site of mAb KS13. All the analyzed Id require the association of the H and L chain of mAb KS13 for their expression. The mAb R1-38 and R18-9 were shown to markedly differ in their ability to modulate immune lysis of target cells mediated by mAb KS13. mAb R18-9 did not affect C-dependent lysis of cultured B lymphoid cells WALK mediated by mAb KS13, but enhanced cell-dependent mAb KS13-mediated lysis. mAb R1-38 inhibited both C and cell-dependent lysis mediated by mAb KS13. The effect was influenced by the incubation conditions. mAb R1-38 completely inhibited lysis when it was preincubated with mAb KS13 before being added to target cells, inhibited it partially when it was added simultaneously with mAb KS13 to target cells and did not affect it when added to target cells which had been preincubated with mAb KS13. Neither mAb R1-38 nor R18-9 in combination with mAb KS13 modulated T cell proliferation induced by allogeneic HLA mismatched lymphocytes. The system we have described may represent a useful in vitro model to investigate the mechanism(s) by which antiidiotypic antibodies may influence the outcome of organs transplanted in recipients with a history of humoral presensitization to donor's HLA Ag.  相似文献   
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