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排序方式: 共有109条查询结果,搜索用时 31 毫秒
61.
62.
Horse spleen apoferritin: N-terminal and C-terminal residues 总被引:2,自引:0,他引:2
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64.
The Notch pathway contributes to self-renewal of tumor-initiating cell and inhibition of normal colonic epithelial cell differentiation. Deregulated expression of Notch1 and Jagged1 is observed in colorectal cancer. Hairy/enhancer of split (HES) family, the most characterized targets of Notch, involved in the development of many cancers. In this study, we explored the role of Hes1 in the tumorigenesis of colorectal cancer. Knocking down Hes1 induced CRC cell senescence and decreased the invasion ability, whereas over-expression of Hes1 increased STAT3 phosphorylation activity and up-regulated MMP14 protein level. We further explored the expression of Hes1 in human colorectal cancer and found high Hes1 mRNA expression is associated with poor prognosis in CRC patients. These findings suggest that Hes1 regulates the invasion ability through the STAT3-MMP14 pathway in CRC cells and high Hes1 expression is a predictor of poor prognosis of CRC. 相似文献
65.
The structure of curved interfacial films formed by the adsorption of the simple T and S-LJ fluid between two structureless planar surfaces was investigated by the means of Grand Canonical Ensemble Monte Carlo (GCEMC) simulation. Our specific aim was to study the formation of a semi-spherical droplet on the planer surface. The surfaces were simulated using Steele's U 10-4-3 ( z ) potential. The droplet was created by truncating the surface potential with a sharp circular cut-off. The remainder of the surface consists of an infinitely hard reflective wall, with rectangular periodic boundary conditions (PBCs) in the xy -plain. This system produced three distinct stages in the structure adsorbed curved films, over an increasing range of relative pressure, p ': at low p ' the film consists of circular monolayers with decreasing radii the farther from the surface; at mid range p ', the film closes to semi-spherical interface with a cap of liquid-like fluid at the pole, at p ' low p ' the film consists of circular monolayers with decreasing radii the farther from the surface; at mid range p ', the film closes to semi-spherical interface with a cap of liquid-like fluid at the pole, at p ' above the saturated vapour pressure of the bulk fluid, a liquid-gas (LG) film of cylindrical symmetry forms an "hour-glass" interface bridging the droplets on opposite surfaces. 相似文献
66.
M. Theuer I. Pilz E. Schwarz P. Wilhelm M.G. Mainwaring S.N. Vinogradov 《International journal of biological macromolecules》1985,7(1):25-29
The extracellular haemoglobin of Tubifex tubifex and the product of its reassociation at neutral pH subsequent to dissociation at alkaline pH, were examined by small-angle X-ray scattering. The following molecular parameters were determined for the native and reassociated molecules, respectively: maximum diameter 30.0±1.0 and 32.0±1.0nm; radius of gyration 10.66±0.15 and 11.07±0.15 nm; molecular weight (3.09±0.15) × 106 and (2.99±0.15) × 106 dalton. Although the scattering curves of the native and reassociated haemoglobin possess similar shapes the distance distribution functions exhibit slight differences in their shape as well as in the position of their maximum. The best fit with the experimental distribution functions was obtained with models consisting of 12 spheres arranged in two hexagonal layers. In the case of the native haemoglobin each of the 12 spheres has a diameter of 9.3 nm while for the reassociated haemoglobin each of the 12 spheres has a diameter of 11.5 nm. The results suggest that although their molecular weights are the same, the reassociated molecule is slightly larger than the native molecule 相似文献
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68.
The long-held belief that breast cancer is a weakly immunogenic tumor and a poor candidate for immunotherapy should be reappraised. There is ample evidence for the existence of an immune response, which is, however, attenuated by multiple inhibitory factors. Many tumor-associated antigens (TAA) have been identified in breast cancer, some of which appear to play a critical role in tumorigenesis and may be attractive targets for immunotherapy. There is evidence for DC recruitment and activation within breast cancers, and the presence of intratumoral activated DCs impacts favorably upon survival. Furthermore, there is a striking paucity of activated DCs within the primary draining or sentinel lymph nodes of breast cancers. Tumor infiltrating lymphocytes (TIL) are often documented, however, their function is impaired by inhibitory cytokines, increased regulatory T lymphocyte activity, tumor cell MHC molecule alterations, and aberrant Fas ligand expression, amongst others. DCs are recognized as one of the critical interfaces between a cancer and the immune system, and have emerged as a promising platform for cancer vaccination via ex vivo immunomodulation. Clinical evaluation of DC vaccination in breast cancer is still relatively limited, although evolving. This article details evidence for the immune response in breast cancer and its many failings, and reviews the clinical trials and significant preclinical data which, taken together, validate the concept of DC vaccination in breast cancer. 相似文献
69.
J J Lightbody E L Ziaja S D Lugo M G Mainwaring S N Vinogradov F Shishikura D A Walz T Suzuki T Gotoh 《Biochimica et biophysica acta》1986,873(3):340-349
Murine monoclonal antibodies to the extracellular hemoglobin of Lumbricus terrestris were prepared by a modification of the method of Kohler and Milstein. 224 hybridomas were found to produce antibodies which bound to the hemoglobin; they were tested for binding to the four subunits of the hemoglobin: M (chain I, 16 kDa), D1 (chain V, 31 kDa), D2 (chain VI, 37 kDa) and T (50 kDa), a disulfide-bonded trimer of chains II, III and IV, each of about 17 kDa. 150 hybridomas bound to all four subunits and 40 hybridomas bound to various combinations of subunits. The remaining 34 hybridomas combined only with the hemoglobin. The twelve hybridomas obtained after subculturing and cloning were tested for their binding to the two fractions II and III, consisting of subunits D1 + D2 + T and M, respectively, obtained by dissociation at pH 9.5 and at pH 4.0 and to the reassociated whole molecules, obtained subsequent to return to neutral pH. Eight hybridomas which combined only with the hemoglobin also combined with all the reassociated molecules but not with any of the fractions: these monoclonal antibodies probably recognize conformation-dependent antigenic sites that are present only in the hexagonal bilayer structure characteristic of the native and reassociated hemoglobin molecules. Of the remaining four hybridomas, two bound to subunit T and two combined with subunits T and D2; they also combined with the reassociated molecules and with the fractions II. In addition, the hybridomas did not bind to the hemoglobins of Tubifex, Limnodrilus, Arenicola, Tylorrhynchus and Macrobdella or to the chlorocruorins of Myxicola and Eudistylia. 相似文献
70.
The extracellular haemoglobins of Lumbricus and Tylorrhynchus contain 50 and 61 tightly bound calcium atoms per molecule, respectively. In addition, they contain one to four tightly bound copper and zinc atoms. Although the role of the latter is unknown, that of calcium is probably structural, assisting in the maintenance of the native hexagonal bilayer structure. 相似文献