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Kiyoshi Takahashi Katsuya Miyatani Hiroyuki Yanai Ho Jong Jeon Kotaro Fujiwara Tadashi Yoshino Kazuhiko Hayashi Tadaatsu Akagi Ken Tsutsui Koichi Mizobuchi 《Virchows Archiv. B, Cell pathology including molecular pathology》1992,62(1):105-113
Monocytic leukemia (MoL) cells were obtained from the peripheral blood of a patient in whom the leukemic cells infiltrating
various lymphoreticular organs exhibited features intermediate between interdigitating reticulum cells (IDC) and ordinary
phagocytic macrophages, whereas the leukemic cells in the peripheral blood were essentially monocytic and lacked such features.
Peripheral blood CD4+ T-cells were established as an interleukin-2-dependent T-cell line. When the MoL cells were exposed
for a few days to conditioned medium from the T-cell line, they extended several dendritic cytoplasmic projections and became
intensely positive for HLA-DR antigen, cytoplasmic S-100β protein, and CD1 antigen. Functionally, the conditioned medium significantly
down-regulated Fc-mediated and Fc-independent phagocytic activities, and the levels of lysosomal enzymes such as lysozyme
and nonspecific esterase in the MoL cells. Moreover, the conditioned medium significantly up-regulated the accessory cell
function of the MoL cells as measured by the primary allogenic mixed leukocyte reaction (MLR). Furthermore, the conditioned
medium significantly down-regulated the expression of CD14 antigen.
Biochemical analysis indicated that the factor responsible for these changes is a protein which is distinct from known human
cytokines and whose molecular weight is approximately 31 kDa. These findings suggest that IDC are closely related the monocytic
lineage and that helper T-cells play an important role in constructing the microenvironment of T-lymphoid tissues which is
necessary for the differentiation and maturation of IDC. 相似文献
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A minority of 46,XX true hermaphrodites are positive for the Y-DNA sequence including SRY 总被引:4,自引:0,他引:4
Ken McElreavey Raphaël Rappaport Eric Vilain Nacer Abbas François Richaud Stéphen Lortat-Jacob Roland Berger Maryvonne LeConiat Chafika Boucekkine Kiran Kucheria Samia Temtamy Claire Nihoul-Fekete Raja Brauner Marc Fellous 《Human genetics》1992,90(1-2):121-125
Summary A total of 30 cases of 46,XX true hermaphroditism was analysed for Y-DNA sequences including the recently cloned gene for male testis-determination SRY. In 3 cases, a portion of the Y chromosome including SRY was present and, in 2 cases, was localised, to Xp22 by in situ hybridisation. Since previous studies have shown that the majority of XX males are generated by an X-Y chromosomal interchange, the Xp22 position of the Yp material suggests that certain cases of hermaphroditism can arise by the same meiotic event. The phenotype in the 3 SRY-positive cases may be caused by X-inactivation resulting in somatic mosaicism of testis-determining factor expression giving rise to both testicular and ovarian tissues. Autosomal or X-linked mutation(s) elsewhere in the sex-determining pathway may explain the phenotype observed in the remaining 27 SRY-negative cases. 相似文献
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Immunocytochemical observation of paraquat-induced alveolitis with special reference to class II MHC antigens. 总被引:1,自引:0,他引:1
A Nakayama H Nagura T Yokoi M Ito J Asai 《Virchows Archiv. B, Cell pathology including molecular pathology》1992,61(6):389-396
The expression of class II major histocompatibility complex (MHC) antigens on alveolar epithelial cells and macrophages was investigated immunocytochemically in paraquat-induced alveolitis in the rat lung. Until 2 days after paraquat injection, class II MHC antigens were expressed on the type II alveolar epithelium without any inflammatory cellular infiltration. From the 4th to the 7th day after paraquat injection, class II MHC antigen-positive macrophages increased in the alveolar spaces, whereas the expression on the type II alveolar epithelium became obscure. Over 10 days after the injection, interstitial fibrosis progressed and the intra-alveolar inflammatory infiltrates decreased. Epithelial cells lining the thickened fibrous septa no longer expressed class II MHC antigens. These results suggest that chemical stimuli can induce class II MHC antigen expression on the type II alveolar epithelium in the early stage of cellular injury, followed by inflammatory infiltration and interstitial fibrosis. 相似文献
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Augmentation rhinoplasty: observations on 1200 cases 总被引:1,自引:0,他引:1
Over the past 14 years, from January of 1975 to December of 1988, we have done 1263 aesthetic rhinoplasties using ear cartilage. In the field of augmentation rhinoplasty, many kinds of materials, such as bone, septal cartilage, ear cartilage, and prostheses, were used. In this paper, we limit discussion to our experience with the technique for the augmentation of the nasal dorsum using the ear cartilage and compare this with other materials. Patient ages ranged from 15 to 72 years, with an average of 24 years. Some 95 percent of patients (1199) were female, and only 5 percent (64) were male. Patients were followed for a minimum of 6 months and a maximum of 20 months, with average follow-up only 8 months. Of course, we know that this is a very short follow-up period, but we could not follow patients longer because if they had no complaint about the results at the 6-month visit, they never returned, despite our efforts. Five-hundred and ten of the 1263 patients (40 percent) had been augmented elsewhere, and the silicone prosthesis was already in place. However, 753 patients (60 percent) had no previous operation. For the 510 patients (secondary rhinoplasty patients), too-high or too-large a prosthesis was the largest complaint in number, totaling 378 cases (74 percent), and psychological dissatisfaction, such as pain or an uncomfortable sensation, was the second largest in number, totaling 104 cases (20 percent). For the 753 patients (primary rhinoplasty patients), the main complaint was too-short or too-flat a nose (100 percent).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Mammalian cell expression cloning has become a standard technique for the isolation of mammalian genes or cDNAs. Its advantage is that the biological functions of the gene of interest are used for cloning. Therefore, the identified cDNAs or genes should be functional in vivo, and there is no need for physical or chemical information about the gene products, so that protein purification in sufficient quantity to raise antibodies or to obtain amino acid sequences is not necessary. Here, we summarize recent progress in mammalian cell cloning systems, and discuss the possible directions in which this technique will lead. 相似文献
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