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51.
Edith Jünger Branka Bajer-Rapi und Erich Richard Schmid 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1975,157(5):281-285
Zusammenfassung Ein Nachweis für Carbamat-Pesticide mittels Enzym-Inhibition auf imprägnierten Cellulose-Schichten wurde ausgearbeitet. Bei Celluloseschichten, die mit Äthylglykol, Triäthylglykol und,-Ogydipropionitril imprägniert waren, erwies sich die Kombination Schweineleberesterase/Indophenylacetat (als chromogenes Substrat) als besonders empfindlicher Nachweis. Die Nachweisempfindlichkeit wurde in Abhängigkeit von der Art des Enzympräparates, des Substrates, des pH, der Inhibitionszeit und -temperatur, der Schichtdicke und des Impriignierungsmittels untersucht.
Herrn o.Univ.-Prof. Dr. O. Hoffmann-Ostenhof, Vorstand des Instituts für Allgemeine Biochemie, Universität Wien, zum 60. Geburtstag gewidmet.
Wir danken dem Fonds zur Förderung der wissenschaftlichen Forschung, der uns die Durchführung dieser Arbeit (Projekt Nr. 2161) ermöglichte.
Ing. B. Rapié dankt der SEA-Stiftung (Scientific Exchange Agreement) für die Gewährung eines Stipendiums. 相似文献
Enzymatic detection of carbamate pesticides on impregnated cellulose plates
Summary The detection of carbamate pesticides by an enzyme-inhibition method on impregnated (ethylene glycol, triethylene glycol,,-ogydipropionitrile) cellulose thin layer plates is described. The enzyme-substrate combination: pig liver esterase-indophenylacetate (chromogenic substrate) was the most sensitive. The following parameters concerning the sensitivity of the method were investigated: enzyme source, substrate, pH, inhibition time, inhibition temperature, thickness of the cellulose layer, stationary phase.
Herrn o.Univ.-Prof. Dr. O. Hoffmann-Ostenhof, Vorstand des Instituts für Allgemeine Biochemie, Universität Wien, zum 60. Geburtstag gewidmet.
Wir danken dem Fonds zur Förderung der wissenschaftlichen Forschung, der uns die Durchführung dieser Arbeit (Projekt Nr. 2161) ermöglichte.
Ing. B. Rapié dankt der SEA-Stiftung (Scientific Exchange Agreement) für die Gewährung eines Stipendiums. 相似文献
52.
We investigated which structural components are responsible for maintaining interstitial fluid equilibrium in the pulpal tissue, for which the existence of an effective lymph drainage is postulated. There have been only a small number of investigations on pulpal lymph tissue. Therefore, we decided to perform a detailed structural analysis. Twenty vital, healthy teeth that had to be extracted for orthodontic reasons were immersed in Patent Blue for 10 to 15 minutes after opening the pulpal cavity. They were then extracted and the dental pulps were opened by cleavage of the surrounding hard tooth structure. Subsequently, the specimens were prepared for light and electron microscopic investigation. A clear blue ring of stain was detected by light microscopy in Weil's zone in the coronal region of the pulp, the cell-rarefied layer surrounded by the odontoblasts. No dye deposition was observed in the apical part. However, using transmission electron microscopy, capillary structures with typical morphological characteristics of lymphatic vessels were found apically. The coronal part of the pulp did not reveal any such vascular structures. It may be concluded from these findings that the lymph in the coronal region is collected in interstitial tissue clefts and drained towards the apex, whence it is further transported via lymph capillaries. 相似文献
53.
54.
Erich Ulrich 《Forschung im Ingenieurwesen》1973,39(2):62-65
Ohne Zusammenfassung
Zuschriften und Entgegnungen erscheinen ohne Verantwortung der Schriftleitung. 相似文献
55.
Langenbucher James; Martin Christopher S.; Labouvie Erich; Sanjuan Pilar M.; Bavly Lawrence; Pollock Nancy K. 《Canadian Metallurgical Quarterly》2000,68(5):799
The Diagnostic and Statistical Manual of Mental Disorders-IV (DSM-IV) classifies as dependent many cases of mild alcohol problems. DSM-IV diagnoses have modest relationships with predictive and some concurrent validators and often improperly sequence the onset of abuse vs dependence, perhaps due to insufficient emphasis on physiological features. Testing reliability, syndrome prevalence, syndrome sequencing, and concurrent and predictive validity, this study contrasted the DSM-IV with the Withdrawal-Gate Model (WGM), in which alcohol withdrawal is necessary and sufficient for the dependence diagnosis. Clinical samples of adults (baseline n?=?318) and adolescents (baselinen?=?214) meeting abuse or dependence were assessed for DSM-IV alcohol symptoms and external measures of problem severity and reinterviewed at 6 (adults) and 12 mo (adults and adolescents). Among DSM-IV dependent cases, the WGM shifted 32% of adults and 80% of adolescents to the abuse category, making both categories more symptomatically severe, but had a negligible effect on prevalence of total alcohol diagnoses. The WGM was more reliable than the DSM-IV and temporally sequenced abuse before dependence in a greater number of cases. The WGM was superior to the DSM-IV in concurrent and predictive validity on most measures. Future diagnostic systems may be more reliable and valid if they require evidence of withdrawal for substance dependence. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
56.
Hamid Ahmadi Wolfgang E. Denzel Charles A. Murphy Erich Port 《International Journal of Communication Systems》1989,2(4):277-287
This paper describes an architecture for a high-performance switching fabric that can accommodate circuit-switched and packet-switched traffic in a unified manner. The switch fabric is self-routeing and uses fixed-length minipackets within the switching fabric for all types of connections. Its kernel architecture is based on a routeing topology with individual connection paths from all inputs to all outputs and with FIFO queuing at each output. Owing to the disjoint connection paths, there is no internal blocking, and because of output queueing, output port blocking is prevented to a great extent. The uniformity in architecture allows construction of any size fabric from a single basic module which could be realized on a single chip. Larger-size configurations can be realized either as single-stage or multistage configuration. The second part of this paper discusses performance aspects and gives results and dimensioning guidelines for both circuit-switched and packet-switched traffic. 相似文献
57.
Michael Hofstätter Andreas Nevosad Christian Teichert Peter Supancic Robert Danzer 《Journal of the European Ceramic Society》2013,33(15-16):3473-3476
Due to the scatter of properties of individual grain boundaries, a scatter of the behavior of low-voltage varistor components and asymmetric current–voltage characteristics with respect to the electrical field direction is observed. Using complementary methods (thermography, scanning surface probe microscopy, electron back-scattered diffraction), we investigated the grain boundary behavior of Praseodymium type varistors. Measurements on the relevant grain boundaries revealed a newly observed effect: dependent on the field direction, the main current flows via different spatial paths. 相似文献
58.
Dilute THF-solutions of different fractions of polymers of methyl, ethyl, n-propyl, n-, i- and t-butyl, n-hexyl, 2-ethylhexyl, and lauryl acrylate, prepared by solution polymerization in benzene, were studied by light scattering and viscosity methods. Poly(acrylic acid) was examined in dioxane. For the different polyacrylic esters the [η]-Mw-relations were established and the dependence of the radius of gyration <r2w> on the molecular weight was determined. 相似文献
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