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Typical and atypical carcinoids (TC, ATC) and small (SCLC) and large cell neuroendocrine carcinomas (LCNEC) constitute the spectrum of neuroendocrine lung tumors. Chromosomal aberrations have not been studied in LCNEC and only rarely in carcinoids. Only SCLCs have been investigated frequently for chromosomal aberrations. We compared three typical and four atypical carcinoids, one atypical carcinoid/SCLC mixed type, three SCLC, and three LCNEC for chromosomal gains and losses using comparative genomic hybridization. Typical carcinoids showed either no changes or only few chromosomal gains. Atypical carcinoids appeared genetically heterogeneous: One case had no aberrations, and three cases had few aberrations; two of them showed a deletion of 11q. SCLC and LCNEC were characterized by many gains and losses, especially similar changes of 3p, 5q, 5p, and 13q. Although ATC resemble LCNEC morphologically, there were no similarities at the genetic level. We have found a reciprocal relationship of prognosis and the amount of aberrations. TCs and ATCs with few chromosomal changes have the best prognosis, whereas SCLCs and LCNECs were generally characterized by a great amount of aberrations and worst prognosis. There was no unbalanced aberration common in all types of neuroendocrine tumors of the lung.  相似文献   
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Zusammenfassung Ätherextrakte von erhitzten wäßrigen Glucose-Glykokoll-Lösungen wurden auf papierchromatographischem Wege untersucht und in einfachen, eindimensionalen Chromatogrammen eine Auftrennung vorgenommen. Mit einer einzigen Ausnahme konnte jedoch — insbesondere auf Grund der ermitteltenR F-Werte — keine Übereinstimmung mit den vonChichester, Stadtman undMackinney angegebenen Verbindungen festgestellt werden. Die von verschiedenen Autoren beschriebene Bildung von Hydroxymethylfurfurol im Verlauf der Maillard-Reaktion konnte bestätigt werden.Eine Verbindung von reduktonähnlichem Verhalten konnte nachgewiesen werden. Ihr könnte die Struktur eines Kondensationsproduktes von Hydroxymethylfurfurol mit Glykokoll zugeschrieben werden. Ein solches wurde vonGottschalk undPartridge papierchromatographisch bei der Maillard-Reaktion in alkalischem Medium nachgewiesen. Der Beweis für seine Bildung in schwach saurem Bereich kann durch vorliegende Untersuchungen als erbracht gelten. Ob diese Verbindung sekundär durch Umlagerung von vorhandenem Glucosid oder jedoch bevorzugt durch Kondensation aus primär entstandenem Hydroxymethylfurfurol mit Glykokoll gebildet wird, wurde im Rahmen vorliegender Untersuchung noch nicht geklärt.Herrn Professor Dr.A. Janke, dem Vorstand des Instituts für Biochemische Technologie und Mikrobiologie, zur Vollendung des 70. Lebensjahres in Verehrung gewidmet.  相似文献   
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Replicated distributed object systems are deployed to provide timely and reliable services to actors at distributed locations. This paper treats applications in which data updates are dependent on satisfaction of integrity constraints over multiple objects. Network partitions, caused by occasional link failures, overload or attacks create problems in keeping both consistency and availability in such networks. We propose a means of achieving higher availability by providing partition‐awareness in middleware. The general approach has been illustrated by implementing a number of CORBA extensions that trade consistency for availability during network partitions. This paper contains a thorough experimental evaluation that presents the gains and costs of our approach. The experiments clearly illustrate the benefit of our protocols in terms of significantly higher availability and the number of performed operations. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
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The objective of this research was to investigate the effect of temperature, pressure, initiator concentration and agitation rate, in ethylene-vinyl acetate emulsion copolymerization, on copolymer composition. The inline React-IR ATR system was used to monitor the reaction as well as to determine residual free vinyl acetate. Pressure, temperature and agitation rate have great influence on mass transfer of ethylene monomer to the reaction sites. The vinyl acetate was introduced in semi-batch mode as well as ethylene since the copolymerization was carried out under a constant pressure of ethylene. The higher temperature results in lower content of ethylene incorporated in copolymer. Increase of pressure has a direct effect on the ethylene content in the copolymers through increasing solubilization of ethylene monomer which in turn increases ethylene content in the copolymers. Copolymers of up to 15 wt.% of ethylene content have been synthesized at an ethylene pressure of 30 bar and a temperature of 75 °C. Analytical methods, such as differential scanning calorimetry, nuclear magnetic resonance, thermogravimetric analysis, and infrared spectroscopy were used for characterization of copolymers.  相似文献   
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The lyophilization of lactose and mannitol aqueous solutions was investigated with an emphasis on analyzing the effects of controlled nucleation, temperature of nucleation, and pore size distribution on the freeze-drying process. The experimental procedure involved the depressurization technique of controlled nucleation, in-vial temperature measurements as well as measurements of the chamber pressure, which allowed the analysis of the product batch, loaded in the laboratory lyophilizator. The average pore enlargement was 93 and 58% with the incorporation of the controlled nucleation step in the lyophilization of 6?wt% lactose and 6?wt% mannitol solutions, respectively. Consequently, the primary drying times were lowered from 450 to 500?min in both cases. The pore sizes were determined to be as important as the solid material itself in the scope of the sublimation rates. Namely, the average equivalent diameter of the pores was larger in the dried mannitol cake compared to the lactose cake. However, despite the higher porosity of the dried mannitol cake, the end of the sublimation in the primary drying step was observed approximately 500?min earlier during the lyophilization of the lactose solution with the same initial concentration as the mannitol solution in a comparable freeze-drying protocol. In addition, an increase in mannitol concentration from 3 to 12?wt% was found to substantially extend the time required for the sublimation phase of the lyophilization.  相似文献   
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Diffusion coefficient measurements have been shown to be strongly influenced by boundary layer resistance and concentration dependence. When half-times for desorption or absorption are used to find diffusion coefficients from the equation for a constant coefficient (T½ = Dt/L2 = 0.049), the values so obtained require correction. Diffusion coefficients found by the “time-lag” method are also influenced strongly by surface resistance and concentration dependence. The usual equation for a constant diffusion coefficient gives a break-through curve with an extrapolation to the time-lag, TL = Dt/L2 = 1/6. This factor can rise to ½ for concentration dependence. Where boundary layer resistance is encountered, (a situation which appears to be quite common), TL is significantly increased and the slope at steady state is decreased.  相似文献   
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