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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   
3.
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   
4.
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   
5.
Summary Spontaneous copolymerizations of cyclic acyl phosphonite (SPO) and phosphite (SPI) with an electron-deficient vinyl monomer such as methyl acrylate (MA), methyl vinyl ketone (MVK), and acrolein (AL), gave the corresponding alternating copolymers. These copolymerizations took place without added initiator and proceeded through zwitterion intermediates. Copolymer structures 1a, 1b, 2 and 3 have been established, all of which were derived in a regiospecific manner of ambident anions. The scheme of the copolymerizations is presented.  相似文献   
6.
Calcium is the most important in-situ catalyst for gasification of US coal chars in O2, CO2 and H2O. It is a poor catalyst for gasification of chars by H2. Potassium and sodium added to low-rank coals by ion exchange and high-rank coals by impregnation are excellent catalysts for char gasification in O2, CO2 and H2O. Carbon monoxide inhibits catalysis of the CH2O reaction by calcium, potassium and sodium; H2 inhibits catalysis by calcium. Thus injection of synthesis gas into the gasifier will inhibit the CH2O reaction. Iron is not an important catalyst for the gasification of chars in O2, CO2 and H2O, because it is invariably in the oxidized state. Carbon monoxide disproportionates to deposit carbon from a dry synthesis gas mixture (3 vol H2 + 1 vol CO) over potassium-, sodium- and iron-loaded lignite char and a raw bituminous coal char, high in pyrite, at 1123 K and 0.1 MPa pressure. The carbon is highly reactive, with the injection of 2.7 kPa H2O to the synthesis gas resulting in net carbon gasification. The effect of traces of sulphur in the gas stream on catalysis of gasification or carbon-forming reactions by calcium, potassium, or sodium is not well understood at present. Traces of sulphur do, however, inhibit catalysis by iron.  相似文献   
7.
This paper describes a self-aligned fabrication process for diamond gated field emitter array (FEA). Utilizing the non-conformal coverage sputtering conditions of silicon oxide, an interesting “sphere on cone” structure is formed on diamond nano tip array, which is the key point of gate hole opening process. This structure causes shadowing at certain regions of side-wall during Ti / Au gate metal deposition. Removal of “sphere” by wet etching leads to the successful fabrication of a single crystalline diamond gated FEA. Scanning electron microscope observations reveal the fabrication of a uniform emitter array with tip radius of curvature (20 nm) and gate hole (1.4 μm). We also confirmed that no noticeable physical damage exists on tip. In field emission characteristics of the fabricated single crystal diamond gated FEA, gate voltage control of field emission current is realized.  相似文献   
8.
To come out with a successful organic light‐emitting diode (OLED) lighting business, it is very important to have clear differentiation of OLED from LEDs. Flexible OLED has merits, such as capability to be mounted on the curved wall, which is not easy for LEDs to achieve the feature. There are several approaches to make flexible OLEDs especially among those plastic barrier films that can bring high level of flexibility, which could not be achieved by any conventional lighting method. In this paper, barrier films with various water vapor transmission rate values, including 10? 6 order, are applied, and the conditions to have almost no dark spot growth under 85 °C and 85% high temperature/humidity test are shown. Flexible OLED panels are manufactured with the world's first roll‐to‐roll equipment using plastic barrier film.  相似文献   
9.
For the effective use of short-lived radioactive beams, soon to be available at the Tokai Radioactive Ion Accelerator Complex, the authors have developed a radiotracer method for diffusion studies in solids. The experimental test was performed by the measurement of the diffusion coefficients of Li in a sample of the compound βLiAl using an α-emitting radiotracer of 8Li (T1/2=0.84 s). It was found that the time-dependent yields of the α particles from the diffusing 8Li that was initially implanted in the sample could be used as a measure of the diffusivity of the tracer in a nondestructive way. The method was applied to measure the self-diffusion coefficients of Li in βLiGa, and for investigating how the Li diffusion in the Li ionic conductors is affected by the concentration of atomic defects (i.e., the existence of the atomic vacancies of Li and the defects in Ga sites that are replaced by Li).  相似文献   
10.
People routinely carry mobile devices in their daily lives and obtain a variety of information from the Internet in many different situations. In searching for information (content) with a mobile device, a user’s activity (e.g., moving or stationary) and context (e.g., commuting in the morning or going downtown in the evening) often change, and such changes can affect the user’s degree of concentration on his or her mobile device’s display and information needs. Therefore, a search system should provide the user with an amount of information suitable for the current activity and a type of information suitable for the current context. In this study, we present the design and implementation of a content search system that considers a mobile user’s activity and context, with the goal of reducing the user’s operation load for content search. The proposed system switches between two kinds of content search systems according to the user’s activity: the location-based content search system is activated when the user is stationary (e.g., standing and sitting), while a menu-based content search system is activated when the user is moving (e.g., walking). Both systems present information according to user context. The location-based system presents detailed information via menus and a map according to location-based categories. The menu-based system presents only a few options to enable users to get content easily. Through user experiments, we confirmed that participants could get desired information more easily with this system than with a commercial search system.  相似文献   
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