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1.
Application of the polymerase chain reaction (PCR) method for detection of subgenus B adenoviruses (types 3, 7 and 11) was investigated. It is based on a simple (nonnested) PCR using primer pairs specific for the hexon-coding region. The PCR allowed amplification of DNA from subgenus B adenovirus prototype strains (types 3, 7 and 11) and adenovirus isolates (types 3 and 7), whereas it did not amplify DNA from subgenus A (type 31), C (types 1, 2, 5 and 6), D (types 8, 19 and 37), E (type 4) and adenovirus isolates (types 1, 2, 5 and 6). These results suggest that subgenus B adenoviruses (types 3, 7 and 11) are detectable selectively by means of PCR with primer pairs developed in this study. Amplified fragments from adenovirus types 3, 7 and 11 could be differentiated with restriction endonuclease analysis with Rsa I.  相似文献   
2.
HuIL-6 cDNA, cloned into a neomycin resistant conferring expression vector, BMGNeo, was transfected into Lewis Lung Carcinoma (LLC) cells. LLC cells (5 x 10(6) ml-1) transfected with IL-6 cDNA (LLC-IL6) secreted IL-6 into the culture supernatant at a concentration of 9.9 ng ml-1 within 48 h. When 1,000,000 of untransfected LLC, BMGNeo vector transfected LLC (LLC-Neo) or LLC-IL6 cells were transplanted into C57BL/6 mice subcutaneously, the mean +/- s.d. of survival times of these mice were 33.3 +/- 9.7, 34.3 +/- 7.1 and 17.0 +/- 3.1 days, respectively. The survival time of LLC-IL6 cells transplanted mice was significantly shorter than that of LLC (P < 0.01) or LLC-Neo (P < 0.01) cells transplanted mice without a measurable difference of tumour size. Plasma concentration of IL-6 steadily increased in LLC-IL6 transplanted mice. Body weight and serum albumin were significantly lower in LLC-IL6 transplanted mice than in LLC transplanted mice. Mouse IL-1 alpha and mouse TNF-alpha were not detected in the plasma of LLC-IL6 transplanted mice. These data suggested that secretion of IL-6 from LLC cells was unable to alter net tumour growth rate but rather caused a state similar to cachexia without detectable increase of IL-1 alpha and TNF-alpha in the plasma. This state may be responsible for the shortened survival of LLC-IL6 tumour-bearing mice.  相似文献   
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4.
We investigated hepatitis C virus (HCV) infection in 35 patients with hypertrophic cardiomyopathy and 40 patients with ischemic heart disease who were consecutively admitted to our hospital. Frequency of positive anti-HCV antibody was significantly higher in patients with hypertrophic cardiomyopathy (6 of 35 patients, 17.1%) than that in patients with ischemic heart disease (1 of 40 patients, 2.5%, p = 0.036). In three of these six patients with hypertrophic cardiomyopathy, HCV RNA was detected in myocardial tissue. In two of these three patients, HCV RNA was detected from biopsy and autopsy specimens of the ventricles, but not in the serum, suggesting that HCV may replicate in myocardial tissue and may be relevant to ventricular hypertrophy. Thus, HCV infection may play a role in the development of hypertrophic cardiomyopathy.  相似文献   
5.
The Phased-Array L-Band SAR (PALSAR) aboard the Advanced Land Observing Satellite (ALOS) is capable of globally acquiring fully polarimetric data. In order to confirm the ability of L-band polarimetric synthetic aperture radar (SAR) to investigate sea ice before the ALOS launch, we conducted a field experiment using an airborne Polarimetric and Interferometric SAR (Pi-SAR) in the Sea of Okhotsk in 1999. This paper presents the analyzed results of data acquired in that experiment. The extracted polarimetric parameters of several ice types suggested that polarimetric coherences and phase differences between right-right (RR) and left-left (LL) are good candidates for discriminating ice types. The polarimetric anisotropy as well as the beta angle of the first eigenvector calculated in the polarimetric decomposition procedure are alternative parameters that are sensitive to ice type differences. Due to the low depolarization characteristics of open water, it could be discriminated from sea ice by scattering entropy in all incidence angle ranges. From the relation between ice thickness and the polarimetric parameters, we found that backscattering coefficients and vertical (VV) to horizontal (HH) backscattering ratio are highly correlated with ice thickness. Since the ratio is sensitive to ice surface dielectric constants, a simple simulation using the integral equation method surface model was conducted by using the physical parameters of typical sea ice. A two-dimensional ice thickness map was derived from an empirical relation between the VV-to-HH backscattering ratio and ice thickness.  相似文献   
6.
In an assembly line of a just-in-time (JIT) production system, workers have the power and the responsibility to stop the line when they fail to complete their operations within their work zones. This paper deals with a sequencing problem for the mixed-model assembly conveyor line in the JIT production system. In some environment, the most important criterion is the line stoppage rather than the variation of production rates. The problem is to find an optimal sequence of units that minimizes the total line stoppage time. Lower and upper bounds of the total line stoppage time are derived and the branch-and-bound method is applied to the problem. A numerical example is given.  相似文献   
7.
Multiple oxide BaTiO3 gel fibres were prepared by the sol-gel method from Ba(OC2H5)2-Ti(O-isoC3H7)4-H2O-C2H5OH-CH3COOH and Ba(CH3COO)2-Ti(O-isoC3H7)4-H2O-CH3COOH solutions. Relatively long gel fibres of 10cm length were obtained from both solutions in the limited composition region. The latter solution in particular showed a spinnability even when it contained no water. Therefore, the occurrence of spinnability of the solution was considered to be due to the formation of linear polymers composed of bridging acetate groups such as TiO-C(CH3)-O-Ti rather than metalloxane bonding as Ti-O-Ti. Addition of water to the solutions seems to break the bridging acetate bonds and replace some of them by bridging oxygen bonds. The as-drawn gel fibres which were X-ray amorphous crystallized into BaTiO3 ceramic fibres of 5mm average length upon heating above 600 ° C. However, the gel fibres drawn from the sols without water became powdery on heating because of the lack of Ti-O-Ti metalloxane bonds. The crystallization behaviour of the BaTiO3 gel fibres is discussed based on the infrared spectroscopy, X-ray diffraction analysis and thermogravimetric-differential thermal analysis.  相似文献   
8.
The feasibility of a solid polymer electrolyte (SPE) method for Kolbe type reactions was investigated by using Pt-SPE composed with Nafion 415 and platinum. The Kolbe reaction of acetic acid proceeded effectively on one side and both sides Pt-SPE composites. The lower current efficiency was observed on the latter than on the former. Neat acetic acid could also be electrolysed on both sides SPE though the cell voltage was fairly high.A methanolic solution of monomethyl adipate was electrolysed to give dimethyl sebacate on both sides Pt-SPE according to the Brown-Walker reaction. The current efficiency and the terminal voltage increased with the concentration of monomethyl adipate. Pt-SPE behaved as an active electrode of a high roughness factor, eg about 6, for the Kolbe reaction of acetate.  相似文献   
9.
Polypyrrole was chemically synthesized using various oxidizing reagents and examined as a positive electrode material. Physical properties, morphologies and electrochemical characteristics of polypyrrole were greatly influenced by the oxidizing reagent used for polymerization. In general, polypyrrole with a smaller particle size and a larger specific surface area showed better discharge performance than that with a larger particle size and a smaller specific surface area. Polypyrrole was also synthesized on various conducting and nonconducting substrates using Fe(C104)3 as an oxidizing reagent. By using PP nonwoven fabric as a substrate material, a high discharge capacity of 72 mA h g–1 was obtained. Polypyrrole synthesized on only one side of PP nonwoven fabric was able to be used as an electrode.  相似文献   
10.
The electrochemical behavior of B1.0C2.4N1.0 thin film was investigated in acidic, neutral and alkaline solutions. The anodic polarization curve of the film in 1 M NaOH showed the anodic dissolution of the film. The curve of the film in 1 M HCl showed no anodic dissolution. The cathodic polarization curve in 1 M NaCl showed shift to a negative potential side, but the anodic polarization curve was the same as that of Pt. The anodic dissolution in 1 M NaOH depended on potentials, that is, no anodic dissolution was recognized in a potential range of −0.2 to 0.1 V but the dissolution rate increased with increasing potential in a range of 0.1-0.6 V. The anodic current density of the film is directly proportional to the dissolution rate at potentials higher than 0.1 V. The dissolution rate of the film was increased with increasing solution pH.  相似文献   
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