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41.
小剂量辐射对肿瘤细胞K_(562)及肿瘤病人天然杀伤细胞(NK)活性的影响 总被引:2,自引:0,他引:2
已知小剂量辐射可增强机体免疫功能。从对高本底地区的调查发现,该地区居民肿瘤死亡率及某些肿瘤发病率有所降低(1)。NK细胞能直接杀伤肿瘤细胞,在肿瘤免疫中起着重要的作用。本文观察小剂量辐射对肿瘤病人和正常人外周血淋巴细胞NK活性的相对效应以及对人红白血病细胞(K(562)细胞)的影响,以期从体外买验来探索较小剂量辐射对肿瘤治疗的影响 相似文献
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Following up on recent studies of the Zn-rich corners of the Zn-Fe-Ni and Zn-Fe-Si ternary systems, a 450 °C isothermal section
of the Zn-Fe-Ni-Si quaternary phase diagram with the Zn composition being fixed at 93 at.% was determined experimentally using
optical microscopy, scanning electron microscopy (SEM) coupled with energy dispersive x-ray spectroscopy (EDS), and x-ray
diffractometry (XRD). FeSi was found to be in equilibrium with almost all phases in the section, including the T, ζ, Ni-δ,
NiSi2, and FeSi2 phases, as well as the liquid phase (L). Silicon solubilities in the T, ζ, and Ni-δ phases were rather limited. However,
the solubilities of Fe and Zn in the NiSi2 phase, at 4.5 at.% and 7.2 at.%, respectively, were appreciable. The existence of the (L+NiSi2+Ni-δ) three-phase equilibrium state apparently prevents other Ni-Si compounds from entering equilibrium with the liquid at
450 °C. No true quaternary compound was found in the study. 相似文献
44.
ABSTRACT: :
Soybeans ( Glycine max ) were soaked and ground to obtain soymilk. The soymilk was cooked in an open tank and held at 85 to 90 deg;C. Yuba films were picked up in 20 min intervals and dried for 20 min. Yuba films were soaked in chicken-flavor solutions (25% and 35%), and baking soda (BS) solutions (0%, 1%, 2%, and 3% BS), and cooked at 100 °C for 30 min, 60 min, and 90 min. TIA decreased (p < 0.05) with the increase of heating time and BS concentration. In vitro protein digestibility (IVPD) decreased with heating time and BS concentration (p < 0.05). Sensory characteristics were affected by flavor concentration. By using 0% BS, 25% of the chicken flavor concentration, and a short heating time method, meat-like products with low TIA, high IVPD, and good sensory characteristics were obtained. 相似文献
Soybeans ( Glycine max ) were soaked and ground to obtain soymilk. The soymilk was cooked in an open tank and held at 85 to 90 deg;C. Yuba films were picked up in 20 min intervals and dried for 20 min. Yuba films were soaked in chicken-flavor solutions (25% and 35%), and baking soda (BS) solutions (0%, 1%, 2%, and 3% BS), and cooked at 100 °C for 30 min, 60 min, and 90 min. TIA decreased (p < 0.05) with the increase of heating time and BS concentration. In vitro protein digestibility (IVPD) decreased with heating time and BS concentration (p < 0.05). Sensory characteristics were affected by flavor concentration. By using 0% BS, 25% of the chicken flavor concentration, and a short heating time method, meat-like products with low TIA, high IVPD, and good sensory characteristics were obtained. 相似文献
45.
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This paper proposes a robust pilot-assisted channel estimation method for orthogonal frequency division multiplexing (OFDM) signals in Rayleigh fading. Our estimation method is based on nonlinear regression channel models. Unlike the linear minimum mean-squared error (LMMSE) channel estimate, the method proposed does not have to know or estimate channel statistics like the channel correlation matrix and the average signal-to-noise ratio (SNR) per bit. Numerical results indicate that the performance of the proposed channel estimator is very close to the theoretical bit error propagation lower bound that is obtained by a receiver with perfect channel response information 相似文献
48.
Su M.F. Reda Taha M.M. Christodoulou C.G. El Kady I. 《Photonics Technology Letters, IEEE》2008,20(10):761-763
Processing methods used in photonics and nanotechnology possess many limitations restricting their application areas such as high cost, inability to produce fine details, problems with scalability, and long processing time. Proximity field nanopatterning is a lithography method which surpasses these limitations. By using interference patterns produced by a two-dimensional phase mask, the technique is able to generate a submicron detailed exposure on a millimeter-size slab of light sensitive photopolymer, which is then developed like a photographic plate to reveal three-dimensional interference patterns from the phase mask. While it is possible to use simulations to obtain the interference patterns produced by a phase mask, realizing the mask dimensions necessary for producing a desired interference pattern is analytically challenging due to the intricacies of light interactions involved in producing the final interference pattern. An alternative method is to iteratively optimize the phase mask until the interference patterns obtained converge to the desired pattern. However, depending on the optimization technique used, one either risks a significant probability of failure or requires a prohibitive number of iterations. We argue that an optimization technique that is to take advantage of the physics of the problem using machine learning methods (here fuzzy learning) can lead to competent mask design. This technique is described in this letter. 相似文献
49.
Yewang Su Baohua Ji Yonggang Huang Kehchih Hwang 《Journal of Materials Science》2007,42(21):8885-8893
Wet adhesion is widely adopted in biological adhesion systems in nature. Wet adhesion is studied in this paper with the focus
on the effect of different contact shapes (flat, concave, convex, and ring-like) on the adhesion force. The evolution of the
liquid bridge between a fiber tip and substrate during the detaching process shows two transition points. The first transition
from the radius-controlled to the contact-angle controlled process is critical to influence the strength and robustness of
adhesion. We show that a concave shape is more effective than a flat one, while a convex shape has no advantage. A ring-like
contact shape has advantages in a hydrophobic environment and on a rough surface. 相似文献
50.
面向企业信息化实现管理现代化 总被引:1,自引:0,他引:1
为适应社会信息化技术的发展,必须积极推行企业信息化,企业信息化引发管理革命,从而丰富了企业管理现代化的内容。本文论述了上述三方面的内部及演化关系,指出只有面向企业信息化,才能充分实现企业管理现代化。 相似文献