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Systemic chemotherapy with 5-fluorouracil (5-FU) has been the mainstay of treatment for patients with metastatic colorectal carcinoma. Administering the drug in a continuous low-dose schedule has produced better result than bolus therapy. Resistance to short-pulse treatment can also be overcome by prolonged exposure. Recent studies suggest the feasibility of biomodulation of 5-FU with recombinant interferon (rIFN alpha-2a) with improved response. Sixteen patients were treated with continuous 5-FU 250 mg/m2 and rIFN alpha-2a 10 x 10(6) u thrice weekly for a maximum of 24 weeks. Five of them had received bolus 5-FU previously. Nine (82%) of the chemonaive group and 1 (20%) previously treated patient had partial response. The median duration of response was 7 months. Grade II to III mucositis were seen in 44% of the patients and 2 patients developed neurological complications. Although the overall response appeared encouraging, the incidence of toxicity was high. In the absence of further phase III studies, rIFN alpha-2a biomodulation of 5-FU cannot be regarded as standard treatment for patients with metastatic colorectal carcinoma.  相似文献   
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Infrared photoluminescence (PL) measurements were performed on (2ID-oriented superlattices with energy gaps in the range 110–495 meV. Most of the samples with thinner HgTe quantum wells displayed two PL peaks separated by Δhω ≈ 30–65 meV (which generally increased with decreasing well thickness). Both peak energies (Ep) sometimes varied gradually with location on the surface, and in one case three peaks of approximately equal spacing were observed in some locations. The data are consistent with a model which assumes the presence of randomly distributed islands having well thicknesses varying by approximately one monolayer. We find that Ahco and the variations of the spectra with temperature agree well with calculations based on this simple model.  相似文献   
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A.J. Gokhale  R. Mahalingam 《Fuel》1985,64(3):419-421
A fixed-bed coal gasification reactor was set up which specifically simulated the devolatilization zone in a gasifier. Samples (100 g) of lignite coal in three size ranges; ?2+1 mm, ?3+2 mm and ?4+3 mm, were devolatilized in the temperature range 350–550 °C with a steam-oxygen mixture, at 1 atm. The effect of these operating variables on tar yield and composition, melting point, viscosity, specific gravity, and molecular weight distribution was determined. A first-order reaction model was fitted to the experimentally observed total loss in weight of the lignite.  相似文献   
26.
The effects of deposition potentials on the electrochemical, structural, morphological and optical properties of the CdSnSe films are studied. X-ray diffraction patterns revealed a mix of cubic and orthogonal phases for the grown CdSnSe thin films. The refractive index, extinction coefficient, dielectric constant and thereby the optical band gap of the films are calculated from transmittance spectral data recorded in the range 400–1,200 nm by UV–Vis–NIR Spectrometer. The optical band gap energy of CdSnSe thin films is found to be in the range of 1.23–1.25 eV. Morphological studies revealed nano-rod shaped grains occupied over the entire surface of the film with average grain size of 150 nm. The influence of deposition potential on the microstructural properties of CdSnSe is also explained in the paper.  相似文献   
27.
Three-dimensional models with irregular grain geometries and appropriate physical properties are needed to investigate fracture in polycrystalline metals and alloys. Creating such models is challenging but achievable using a two-stage process, suitable for any polycrystal. The processes described in this paper are illustrated by examples of brittle fracture in ferritic steel, zinc and nickel. The predicted crack path in a model is compared with the grain boundary fracture seen in three point bend specimens of nickel embrittled by sulphur.  相似文献   
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In this paper, coupled higher order nonlinear Schrödinger–Maxwell–Bloch equations are studied for the ultrashort pulse propagation in erbium-doped birefringent fiber system. Lax pair is constructed for the CHNLS–MB system. Through the Darboux method and symbolic computation, analytic two-soliton solution is obtained. To analyze the specific problem, we design an optimal system by properly choosing the special form of variable coefficients. Here, using obtained two-soliton solution, tunneling of femtosecond soliton through barrier and well is investigated. While solitons are passing through barrier and well, some unexpected behavior is observed and hidden possibilities in switching action through tunneling is investigated.  相似文献   
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ABSTRACT

A set of runs were performed on the catalytic and thermal cracking of the tars present fn the gasifier off-gas stream; the cracking referred to here Js essentially hydrocracking, in view of the considerable amount of hydrogen being present in the gas stream. The catalyst evaluated for tar cracking was a commercial cobalt-molybdenum catalyst, suppported on γ-Al2O3(Katalco-477). It was observed that there was a decrease in the amount of tar obtained with the cracking unit on-line with the gasifier; the tars were cracked to gaseous products in the presence of catalyst. Furthermore, it appeared that higher ring structures were transformed to less heavier components; thus cracking could become beneficial in downstream processing of the gas stream coming out of a gasifier.  相似文献   
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