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排序方式: 共有1814条查询结果,搜索用时 31 毫秒
1.
Toshiyuki Hamaoka Yasuyuki Takai Atsushi Kosugi Yumiko Mizushima Junko Shima Tsuneo Kusama Hiromi Fujiwara 《Cancer immunology, immunotherapy : CII》1985,20(3):183-188
Summary A new haptenic compound, a muramyl dipeptide (MDP) derivative (designated as L4-MDP-ONB) cross-reactive with Bacillus Calmette Guerin (BCG) was synthesized. The cross-reactivity of L4-MDP hapten to BCG was demonstrated from the following evidence; (a) lymph node cells from BCG-primed C3H/HeN mice exhibited appreciable L4-MDP-specific proliferative responses to the in vitro stimulation of L4-MDP-modified syngeneic cells (L4-MDP-self); (b) inoculation of L4-MDP-self into footpads of BCG-primed C3H/HeN mice elicited ample delayed type-hypersensitivity (DTH) responses in vivo as measured by footpad swelling; and (c) BCG-primed mice contained L4-MDP-reactive helper T cell activity which functions to augment the generation of effector T cell responses to cell surface antigens. This crossreactivity between L4-MDP hapten and BCG as measured by the helper T cell activity was applied to enhanced induction of tumor-specific immunity. When BCG-primed C3H/HeN mice were immunized with L4-MDP-modified syngeneic X5563 tumor cells, these mice could generate augmented tumor-specific in vivo protective (tumor neutralizing) immunity as well as in vitro cytotoxic T cell responses. These results indicate the effectiveness of L4-MDP hapten in augmenting tumor-specific immunity. The present approach is discussed in the context of potential advantages of this new hapten for its future application to clinical tumor systems. 相似文献
2.
Michael F. Seldin Lawrence A. D'Hoostelaere Alfred D. Steinberg Yumiko Saga Herbert C. Morse III 《Immunogenetics》1987,26(1-2):74-78
Allelic variants of Ly-5 in inbred commensal and other natural populations of mice were analyzed by patterns of restriction fragment length polymorphisms (RFLP) and Southern hybridization using an Ly-5 cDNA probe and by cell-surface staining with a panel of antibodies directed against polymorphic and nonpolymorphic Ly-5 determinants. New Ly-5 alleles were defined by RFLPs generated by both Eco RI and Bam HI restriction enzyme digests. The Mus musculus subspecies and other species within the genus Mus showed a strong correlation between allelic variants defined by restriction enzymes and serologic specificities. The data also suggest the conservation of the Ly-5 gene throughout the genus Mus. 相似文献
3.
The low molecular weight carbohydrate compositions of the seeds of 29 species ofVicia, namelyV. amoena, V. amurensis, V. bifolia, V. dumetorum, V. fauriei, V. japonica, V. nipponica, V. pisiformis, V. pseudo-orobus,
V. sylvatica, V. unijuga, V. venosa, V. cassubica, V. orobus, V. cracca agg.,V. hirsuta, V. villosa agg.,V. tetrasperma,V. oroboides, V. sepium, V. cuspidata, V. grandiflora, V. lathyloides, V. sativa agg.,V. bithynica, V. faba, V. narbonensis, V. hybrida andV. lutea were determined by gas liquid chromatography. The carbohydrate compositions were found to be species-specific. Principal
component analysis of the carbohydrate composition data showed that these species can be divided into three groups. Although,
as far as the examined species were concerned, these groups were not correlated with the known subgenera, significant correlation
between the groups and the known sections was detected in the subgenusVicia. The carbohydrate composition character would be important to clarify the relationships among closely related taxa of the
genusVicia. 相似文献
4.
DNA ploidy pattern and amplification of ERBB and ERBB2 genes in human gastric carcinomas 总被引:1,自引:0,他引:1
N Oda T Tsujino T Tsuda K Yoshida H Nakayama W Yasui E Tahara 《Virchows Archiv. B, Cell pathology including molecular pathology》1990,58(4):273-277
The DNA ploidy pattern and amplification of ERBB and ERBB2 genes were examined in paraffin-embedded tissue from gastric carcinomas using flow cytometry and a slot-blot hybridization technique. The incidence of aneuploidy in well differentiated adenocarcinomas (56%) was significantly higher (p less than 0.05) than that in poorly differentiated adenocarcinomas (21%). The DNA ploidy pattern was not remarkably different between the primary tumors and metastatic deposits in lymph nodes. Of the nine specimens having an aneuploid stem cell line in the primary tumor and/or in metastases, three showed ERBB2 gene amplification and one showed ERBB gene amplification. The incidence of epidermal growth factor (EGF) immunoreactivity in tumor cells showed no difference between diploid and aneuploid tumors. These findings indicate that aneuploidy is frequently associated with amplification of ERBB and ERBB2 genes. 相似文献
5.
Masanori Ito Kazuhiro Yoshida Eikai Kyo Ayse Ayhan Hirofumi Nakayama Wataru Yasui Hisao Ito Eiichi Tahara 《Virchows Archiv. B, Cell pathology including molecular pathology》1990,59(1):173-178
We have examined the expression of mRNAs for epidermal growth factor (EGF), transforming growth factor-alpha (TGF-α), EGF
receptor (EGFR), PDGF-A chain (PDGFA), PDGF-B chain (PDGFB) and PDGF receptor (PDGFR) genes in seven human colorectal carcinoma
cell lines and 18 human colorectal carcinomas.
In surgically resected specimens of the 18 colorectal tumors, TGF-α, EGFR, PDGFA, PDGFB and PDGFR mRNAs were detected at various
levels in 15 (83%), 9 (50%), 18 (100%), 8 (44%) and 12 (67%), respectively. They were also detected in normal tissues. Interestingly,
EGF mRNA was detected in only five (28%) of the tumors, but not in normal mucosa. Expression of EGF was also confirmed immunohistochemically
in tumor cells. Of the five tumors expressing EGF, four expressed EGFR mRNA and showed a tendency to invade veins and lymphatics.
All the colorectal carcinoma cell lines expressed TGF-α mRNA, and five cell lines expressed EGFR mRNA simultaneously. Production
of TGF-α protein by DLD-1 and CoLo320DM cells was confirmed by TGF-α specific monoclonal antibody binding assay. The spontaneous3H-thymidine uptake by DLD-1 was suppressed by an anti-TGF-α monoclonal antibody. PDGFA and PDGFB mRNA were also expressed
in four cell lines, but PDGFR and EGF mRNA was not detected. These results suggest that human colorectal carcinomas express
multi-loops of growth factors and that TGF-α produced by tumor cells functions as an autocrine growth factor in human colonic
carcinoma. 相似文献
6.
The structural organization of the cell nucleus was investigated by transmission electron microscopy in the radiosensitive Chinese hamster ovary (CHO) cell mutant, xrs-5 (D0 = 45 cGy), relative to parental K1 cells (D0 = 200 cGy). In 99% of all xrs-5 cells, the outer layer of the nuclear envelope was separated from the inner layer, while 96% of K1 cells had closely apposed layers. This separation of the inner and outer layers of the nuclear envelope in xrs-5 cells was not explained by an increased susceptibility of xrs-5 cells to osmotically induced changes because (1) xrs-5 cells retained the altered nuclear periphery even when several different fixation protocols were used and (2) xrs-5 cells were not more susceptible to cell lysis as measured by trypan blue dye exclusion or by the extracellular presence of lactate dehydrogenase. The difference in the morphological organization in the nuclear periphery of xrs-5 cells correlated with the radiation sensitivity of the cells; xrs-5 cells which spontaneously reverted to a radiation sensitivity similar to that of K1 cells also reverted to a nuclear morphology similar to that of K1 cells. The inner and outer layers of the nuclear envelope were retained in nuclear scaffolds isolated from K1 and xrs-5 cells, indicating that components of the nuclear periphery are part of the nuclear scaffold. These data show that xrs-5 cells have an altered nuclear periphery which correlates with the radiation sensitivity of the cells. The separation of the layers of the nuclear envelope may represent an altered template for repair of DNA damage at the nuclear scaffold and thus may play a role in the defective repair of X-ray-induced DNA double-strand breaks in xrs-5 cells. 相似文献
7.
Hiroyuki Uno Yumiko Ohno Tsuneo Yamada Kensaku Miyamoto 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1991,169(2):231-239
Summary The responses of neurons in field L in the auditory neostriatum of the mynah bird, Gracula religiosa, were recorded during presentation of intact or manipulated mimic voices. A typical mimic voice konnichiwa elicited responses in most of the neurons. Neurons in the input layer (L2) of field L showed many peaks on peristimulus time histograms while those in other layers (L1 and L3) exhibited only one or two peaks. Several neurons in L1 and L3 responded only to the affricative consonant /t/ in the intact mimic voices. They did not respond to the affricative consonant in the isolated segment or to the one in the playbacked voice in reverse. Forty-five percent of the neurons (33/ 73) decreased in firing rates at the affricative consonant in the isolated segment compared with in the intact voice. Some of these neurons, in which neither the affricative consonant in the isolated segment nor bursts of noise alone elicited responses, exhibited clear phasic responses to /t/ in the case when bursts of noise with particular central frequencies preceded the affricative consonant. The responsiveness of these neurons appears to receive temporal facilitation. These results suggest that these neurons code the temporal relationship of speech sound.Abbreviations
HVc
hyperstriatum ventrale, pars caudale
-
TFN
temporally facilitated neuron
-
TSN
temporally suppressed neuron 相似文献
8.
Recessive Nonsense Suppressors in SACCHAROMYCES CEREVISIAE : Action Spectra, Complementation Groups and Map Positions 总被引:4,自引:3,他引:1 下载免费PDF全文
Bun-Ichiro Ono Yumiko Ishino-Arao Masahiro Tanaka Ikuko Awano Sumio Shinoda 《Genetics》1986,114(2):363-374
Three genes SUP111, SUP112 and SUP113 of Saccharomyces cerevisiae have been identified that can mutate to give recessive omnipotent nonsense suppressors. Alleles of these loci can also act as allosuppressors; that is, different phenotypes, due apparently to different efficiencies of suppression, can result from different alleles at a given locus. The SUP111, SUP112 and SUP113 loci map to the right arms of chromosomes VIII, VII and XIII, respectively. 相似文献
9.
K Yasui 《American journal of physical anthropology》1986,71(1):39-49
If the visual image and quantitative treatment of a form could be merged, the combination could become a powerful analytical method in morphology. A method is presented for creating an averaged outline. In this method, since the averaged outline is produced statistically, hypothesis testing can be performed on the visual image of the outlines. Intra- and intergroup variation of the outlines can then be assessed by taking allometry into account. This method is applied to the analysis of sexual differences in the midsagittal outline of recent (1880s-1920s) Japanese crania. The averaged outlines of both sexes showed subtle features that could not be detected by traditional measuring techniques. Because the roundness, flatness, or protrusion of specific aspects of the morphology are clearly apparent, sexual differences in this sample could be identified. Changes resulting from allometry did not seem to be present in either sex. The shape distance (DIR) introduced here matched well the visual impression derived from comparisons of the Japanese sample with a Jomon (Neolithic) male and the Broken Hill specimen. 相似文献
10.
Identification of a large interrupted helical domain of disulfide-bonded cartilage collagen 总被引:3,自引:0,他引:3
In order to characterize a larger form of disulfide-bonded cartilage collagen, explants of 17-day embryonic chick sterna were cultured in the presence of [3H] proline. Radioactive collagen chains and fragments that were synthesized and secreted into the culture medium were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and fluorography. After limited pepsin digestion of the medium, two discrete disulfide-bonded collagen fragments were detected with Mr = 210,000 and 153,000. These fragments contained 28 and 17.5%, respectively, of the radioactivity in the alpha 1(II)-chains. The smaller fragment (called M) produced three components upon reduction (Mr = 104,000, 51,000, and 31,000) and seemed to represent the previously reported collagens, HMW and M1. The larger fragment (called N) has not been previously described and gave rise to three components upon reduction (Mr = 140,000, 69,000, and 49,000). Prolonged pepsin treatment resulted in the gradual decrease of N with a corresponding increase of M, suggesting the conversion of N to M. CNBr peptide mapping demonstrated that all M-derived peptides were present in N and that N contained extra peptides that account for its larger size. These observations suggest that N represents a larger more intact form of cartilage-derived disulfide-bonded collagen. 相似文献