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1.
The levels of mRNA expression of three UDP-N-acetyl-alpha-D-galactosamine:polypeptide GalNAc N-acetylgalactosaminyltransferases (GalNAc-transferases) were quantified for human adenocarcinoma cell lines from pancreas, colon, stomach, and breast. Two of the GalNAc-transferases, GalNAc-T1 and GalNAc-T2, were expressed constitutively and at low levels in most or all cell lines examined. A third GalNAc-transferase, GalNAc-T3, was differentially expressed. Well-differentiated adenocarcinoma cell lines expressed high levels and moderately differentiated cell lines expressed lower levels of GalNAc-T3. Cell lines classified as poorly differentiated failed to express GalNAc-T3 mRNA at levels that could be detected by Northern blot analysis. Differential expression of the GalNAc-T3 protein was confirmed in these cell lines by Western blotting. We propose that glycosylation in tumor cell lines may be regulated in part by differential expression of GalNAc-transferases, and we suggest that GalNAc-T3 gene expression may be a molecular indicator of differentiated adenocarcinoma.  相似文献   
2.
A case of BK virus cystitis in a 5 year old boy is reported. This patient, who was not immunocompromised, had had acute cystitis for two weeks. Many intracytoplasmic inclusions were observed in urinary sediment smears stained by the Papanicolaou method. Electron microscopic examination showed virus particles, presumed to be human polyomavirus, in the nuclei of the degenerated urothelial cells. A DNA sequence of the BK virus was detected in 200-300 urothelial cells in Papanicolaou stained smears by the polymerase chain reaction. BK virus is an unusual cause of symptomatic cystitis in a healthy child.  相似文献   
3.
The authors reports the fabrication of a flip-chip InGaAsP-InAlAs superlattice avalanche photodiode using gas source molecular beam epitaxy. The incident light reaches the InGaAs photoabsorption layer through the InP substrate and an InGaAsP-InAlAs superlattice multiplication region which are transparent for wavelengths of 1.55 and 1.3 μm. The light reflection by the electrode enables the absorption layer to be as thin as 0.8 μm without significantly reducing the quantum efficiency. A maximum bandwidth of 17 GHz was obtained at a low multiplication factor because the transit time through the absorption layer is reduced  相似文献   
4.
By combining the modified Stokes-Einstein formula with the authors’ model for the melting-point viscosity, the authors present a model for accurate predictions of self-diffusivity of liquid metallic elements. The model is expressed in terms of well-known physical quantities and has been applied to various liquid metallic elements for which experimental data are available. The results of calculations show that agreement with experimental data is excellent; the uncertainties in the calculations of the self-diffusivities in various liquid metallic elements are equal to the uncertainties associated with experimental measurements. Also, the authors propose an expression for the temperature dependence of self-diffusivity in liquid metallic elements in terms of melting-point temperature. Using the model, self-diffusivity data are predicted for liquid iron, cobalt, nickel, titanium, aluminum, magnesium, silicon, and so forth.  相似文献   
5.
An odor sensing system using a quartz crystal microbalance (QCM) sensor array and pattern recognition technique has been for years a main research topic in our group. For the general field of artificial olfaction using acoustic-wave based sensors such as QCMs it is vital to search for novel sensing materials. Here we present recent results of our ongoing study on application of pegylated lipids as coatings for QCM odor-sensors. The method presented herein is based on self-assembling of lipids and lipid-derivatives on the QCM surfaces. The disulphide-terminated lipids and lipopolymers are co-chemisorbed onto gold electrodes of QCM sensors by simple immersion in ethanolic solutions. This creates porous supports onto which additional layers of lipopolymers are physisorbed. The method allows for fabrication of lipopolymeric QCM odor-sensors with enhanced sensitivity to odorants, capable of very good discrimination among odorant samples—according to the functional group of an odorant.  相似文献   
6.
Temperature dependence of water vapor sorption and electro-active polymer actuating behavior of free-standing films made of poly(3,4-ethylenedioxythiophene) doped with poly(4-styrenesulfonate) (PEDOT/PSS) was investigated by means of sorption isotherm and electromechanical analyses. The non-porous PEDOT/PSS film, having a specific surface area of 0.13 m2 g?1, sorbed water vapor of 1080 cm3(STP) g?1, corresponding to 87 wt%, at relative water vapor pressure of 0.95. A temperature rise from 25 °C to 40 °C lowered sorption degree, indicative of an exothermic process, where isosteric heat of sorption decreased with increasing water vapor sorption and the value reached 43.9 kJ mol?1, being consistent with the heat of water condensation (44 kJ mol?1). Upon application of 10 V, the film underwent contraction of 2.46% at 5 °C caused by desorption of water vapor due to Joule heating, which slightly decreased to 2.10% at 45 °C. The speed of contraction was one order of magnitude faster than that of expansion and less dependent on the temperature since water vapor sorbed in the film were forced to desorb by Joule heating. In contrast, the higher the temperature the faster the film expansion because diffusion coefficient increased as the temperature became higher.  相似文献   
7.
Due to rapid changes of markets and pressures of competitions, industries are adopting their production ways to support diversity of customer’s needs and increase of new product developments. This paper deals with development of an agent-based architecture of dynamic systems for process planning in the manufacturing systems. In consideration of alternative manufacturing processes and machine tools, the process plans and the schedules of the manufacturing resources are generated incrementally and dynamically. A previously proposed negotiation protocol is customized and improved to generate suitable process plans for the target products real-timely and dynamically, based on the alternative manufacturing processes. The alternative manufacturing processes are presented by the process plan networks and the suitable process plans are searched and generated to cope with both the dynamic status and disturbances of the manufacturing systems. We initiatively combine the heuristic search algorithms of the process plan networks with the negotiation protocols, in order to generate suitable process plans.  相似文献   
8.
In this article, the isothermal flow stress in supercooled austenite was measured for a high hardenability steel. Supercooled austenite forms at the nonequilibrium phase and changes into other phases within a short time. It was confirmed that conventional tensile tests, which require maintaining a constant temperature before stretching, cannot accurately measure the flow stress in supercooled austenite. Therefore, a new tensile test named “the continuous cooling tensile test” was developed. In this test, stretching is conducted during continuous cooling. In the continuous cooling tensile test, the flow stress between 673 K and 973 K (400 °C and 700 °C) was measured. Microscopic observations of the continuous cooling test results verified that the microstructures were supercooled austenite.  相似文献   
9.
We demonstrate the novel dispersion compensation for time-spread/wavelength-hop (TS-WH) optical code-division multiplexing (OCDM). The single-mode-fiber transmission, up to 80 km long, on TS-WH OCDM was achieved by a combination of the dispersion-compensated decoder and the multichannel-type dispersion-slope compensator.  相似文献   
10.
Recently, linear oscillatory actuators have been used in a wide range of applications. In particular, small linear oscillatory actuators are expected to be used in haptic devices by being extended to provide multi‐degree‐of‐freedom motion with arbitrary acceleration. In this paper, we propose a compact two‐DOF oscillatory actuator that can move in various directions on a plane. The static and dynamic characteristics of the actuator are determined by the 3D finite element method. The effectiveness of this method is shown through a comparison of the measured results with the experimental results from a prototype. © 2013 Wiley Periodicals, Inc. Electr Eng Jpn, 186(1): 58–65, 2014; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.22312  相似文献   
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