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排序方式: 共有421条查询结果,搜索用时 31 毫秒
31.
Lahann J Mitragotri S Tran TN Kaido H Sundaram J Choi IS Hoffer S Somorjai GA Langer R 《Science (New York, N.Y.)》2003,299(5605):371-374
We report the design of surfaces that exhibit dynamic changes in interfacial properties, such as wettability, in response to an electrical potential. The change in wetting behavior was caused by surface-confined, single-layered molecules undergoing conformational transitions between a hydrophilic and a moderately hydrophobic state. Reversible conformational transitions were confirmed at a molecular level with the use of sum-frequency generation spectroscopy and at a macroscopic level with the use of contact angle measurements. This type of surface design enables amplification of molecular-level conformational transitions to macroscopic changes in surface properties without altering the chemical identity of the surface. Such reversibly switching surfaces may open previously unknown opportunities in interfacial engineering. 相似文献
32.
33.
Growth characteristics of canine distemper virus in a new cell line CCT cells originated from canine malignant histiocytosis 总被引:1,自引:0,他引:1
Yamaguchi R Kojimoto A Sakai H Uchida K Sugano S Tateyama S 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2005,67(2):203-206
Canine distemper virus (CDV) growth and the morphological characterization were examined in a cell line established from a canine malignant histiocytosis (CCT cell line). The susceptibility of the CCT cells to 3 CDV strains, FXNO, YSA-TC and MD-77 was shown by detection of the antigen in the indirect fluorescent assay. After passaging 4 and 9 times through the CCT cells, only FXNO strain could produce the syncytia where demonstrated the antigens. Titers of 9 passaged viruses through the CCT cells showed slightly higher in the CCT cells than those in Vero cells. Morphological characterization of karyorrhexis and specific DNA ladder by extracted DNA electrophoresis indicated apoptosis in the CDV infected CCT cells. 相似文献
34.
Sato H Miura R Kai C 《Comparative immunology, microbiology and infectious diseases》2005,28(4):311-320
Measles virus (MV) infection primarily targets epithelial cells of the respiratory tract, which have the potential to synthesize a variety of cytokines. In this report, we studied the effect of MV infection on the production of interleukin (IL)-8 by the pulmonary epithelial cells. A549 cells, a lower airway epithelial cell line, produced IL-8 after MV inoculation in a dose- and time-dependent manner. The IL-8 production was little affected by UV-inactivation of MV and scarcely suppressed by cycloheximide treatment. These results indicated that MV particle binding to and/or incorporation into cells stimulated IL-8 expression in A549 cells. 相似文献
35.
Nagaya H Kanaya T Kaki H Tobita Y Takahashi M Takahashi H Yokomizo Y Inumaru S 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2004,66(11):1395-1401
We developed a procedure for the large-scale purification of bovine interferon-tau (boIFN-tau) by means of a silkworm-baculovirus gene expression system. Recombinant boIFN-tau (rboIFN-tau) was efficiently produced in the silkworm infected with boIFN-tau cDNA recombinant baculovirus and accumulated in the haemolymph. To establish a purification method suitable for mass production, we tried three crude purification methods, namely, an acidification and neutralization treatment (ANT), silica gel column chromatography (SGCC), and Blue sepharose column chromatography (BSCC) with a combination of Q-sepharose (QSC) and chelating sepharose column chromatographies (CSCC). As a result, the acidification and neutralization treatment was found to be the most efficient and cost effective. With this combination, we obtained 91% pure products. To confirm the applicability of the procedure for mass production, we inoculated 100 silkworms with the recombinant virus, and recovered about 4.55 mg (1.26 x 10(8)U/mg) of 91% pure rboIFN-tau by means of a combination of the ANT, followed by QSC and CSCC. 相似文献
36.
Ushijima H Yoshioka H Esaki R Takahashi K Kuwayama M Nakane T Nagashima H 《The Journal of reproduction and development》2004,50(4):481-486
An efficient cryopreservation protocol for porcine morulae was investigated with three types of vitrification having different cooling rates (Exp. 1). Survival of embryos vitrified after removal of cytoplasmic lipid droplets was also examined by means of the minimum volume cooling (MVC) method (Exp. 2). In Exp. 1, the morula stage embryos were vitrified with a 0.25 ml plastic straw (ST-method), gel loading tip (GLT-method) and the MVC-method, respectively, and stored in liquid nitrogen after which they were warmed in sucrose solutions with cryoprotectants being subsequently removed in a stepwise manner. In Exp. 2, morulae were centrifuged with 7.5 microg/ml cytocharasin B at 12000 x g for 20 min to polarize the cytoplasmic lipid droplets that were then removed from the embryos by micromanipulation (delipation). Both those delipated at the morula stage and the intact embryos at the morula to blastocyst stages were vitrified by the MVC-method. In vitro survival of the vitrified embryos was assessed in both experiments by culturing in NCSU-23 + 10% FCS for 48 h. In vitro developments of vitrified embryos after warming to blastocysts were 20% (6/30) for the ST-method, 39% (18/46) for the GLT-method, and 60% (26/43) for the MVC-method. Embryo survival was further improved by vitrification after delipation (95%, 35/37) compared to intact vitrified morulae (24/42, 57%, P<0.001) and blastocysts (23/31, 74%, P<0.05). Moreover, the number of cells in blastocysts (92 +/- 25) derived from the delipated-vitrified morulae was comparable to those derived from intact control non-vitrified embryos (103 +/- 31). Our results demonstrate that vitrified porcine morulae have the highest survival when using the MVC-method in conjunction with delipation. 相似文献
37.
Nakamura A Sasaki F Watanabe K Ojima T Ahn DH Saeki H 《Journal of agricultural and food chemistry》2006,54(25):9529-9534
The effect of the Maillard reaction on the allergenicity of squid tropomyosin (TM) was investigated. When TM was reacted with ribose (TM-ribose), its human-specific IgE-binding ability decreased markedly and alpha-chymotryptic digestibility of TM was also altered at the early stage of the Maillard reaction. On the other hand, the modification of the lysine residues in TM using 2,4,6-trinitrobenzenesulfonic acid had no effect on the allergenicity and alpha-chymotryptic digestibility of TM. Therefore, the structural change in TM induced by the Maillard reaction would cause the reduction of the allergenicity, rather than the block of lysine residues. Although peptic digestion diminished the specific IgE-binding ability of TM, the reduction of the allergenicity by the Maillard reaction remained after peptic digestion. These results suggest that hypersensitive reaction of TM-ribose in the human body might be lower than that of native TM. 相似文献
38.
Ushiro Y Hashimoto O Seki M Hachiya A Shoji H Hasegawa Y 《The Journal of reproduction and development》2006,52(4):487-495
Activins, TGF-beta superfamily members, have multiple functions in a variety of cells and tissues. Additional activin beta subunit genes, betaC and betaE, have been identified in humans and rodents. To explore the role of activin betaC subunit, we generated recombinant human activin C using Chinese hamster ovary cells. Recombinant activin C from the conditioned medium was purified by consecutive hydrophobic, size-exclusion, and high performance liquid chromatography. SDS-PAGE and Western blot analysis of the purified protein revealed that activin C formed disulfide bridges. However, activin C had no effect on the proliferation of cultured liver cells. Furthermore, there were no significant differences in erythroid differentiation and follicle stimulating hormone secretion in vitro. It was also shown that immunoreactive bands indicated the hetrodimer of activin betaC, and inhibin alpha subunits were detected in the conditioned medium from the activin C-producing cells, which were stably transfected with inhibin alpha subunit cDNA. This suggests that activin betaC subunit may have been present and that it may exert its effect as inhibin C. 相似文献
39.
Simon B Sano H 《Journal of the American Veterinary Medical Association》2012,240(3):261; author reply 261-261; author reply 262
40.
Minamoto T Honjo MN Yamanaka H Uchii K Kawabata Z 《Research in veterinary science》2012,93(1):508-514
Cyprinid herpesvirus 3 (CyHV-3) disease is a significant threat for common and koi carp cultivators and for freshwater ecosystems. To determine the prevalence of CyHV-3 in Japanese rivers, a nationwide survey of all national class-A rivers was undertaken in the Summer of 2008. The virus was concentrated from river water samples using the cation-coated filter method. CyHV-3 DNA was detected in 90 rivers, representing 90% of 103 successfully analysed rivers. More than 100,000 copies of CyHV-3 DNA per litre of sample were detected in four rivers, higher than that reported during the Yura River outbreak in 2007. For CyHV-3-positive rivers, the log CyHV-3 density was negatively correlated with the water temperature on the sampling date and positively correlated with the suspended solids and dissolved oxygen, which are annually averaged for each river. Our results demonstrate that virus detection using molecular biology techniques is a powerful tool for monitoring the presence of CyHV-3 in natural environments. 相似文献