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101.
Polyclonal immunoglobulin M antibodies to the monosialoganglioside GM2, sulfoglucuronyl glycolipids, and sulfatide were detected by thin-layer chromatography and enzyme-linked immunosorbent assay in the serum of a patient with melanoma and chronic inflammatory demyelinating polyneuropathy. Both the patient's serum and polyclonal antibodies against GM2 reacted strongly with a biopsy of melanomatous tissue from the patient, suggesting a process of molecular mimicry.  相似文献   
102.
The activity of IAA-oxidising enzymes from Lens roots is enhanced in vitro by dalapon (2,2-dichloropropionic acid) and perfluidone (1,1,1 -trifluoro-N-[2-methyl-4-(phenylsulphonyl)phenyl]methanesulphonamide). When concentrations are greater than 10?8 M, both these herbicides act as activators. In vivo higher levels of the enzymatic activity are obtained when seed germination is carried out in the presence of 10?5 M perfluidone or 10?3 M dalapon. Gas-liquid chromatography is used for IAA determination.  相似文献   
103.
Questions the conclusions of A. J. Ward (see pa, vol. 44:12960) concerning the environmental etiology of early infantile autism on the basis of an incomplete and selected coverage of the literature. More recent evidence and different viewpoints suggest a different, or at least transactional, etiology. Different treatment approaches, also not covered in ward's review, may lead toward a more clear-cut differentiation of this syndrome. (21 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
104.
A marina was constructed in the Great Barrier Reef World Heritage Area in close proximity to coral reefs that could be damaged by excess turbidity generated during construction. Since there was uncertainty about both the fate of suspended sediments and their effect on corals, initial water quality constraints were set very conservatively. In order to better understand the movement of suspended sediment during construction, a numerical model study was commissioned using three-dimensional, numerical, hydrodynamic, and Lagrangian particle tracking models. The study was successful in: (1) increasing the understanding of and reducing the uncertainty of sediment dispersal patterns under a range of common forcing conditions; (2) testing the variation in suspended sediment concentrations over sensitive areas for two different outfall locations; (3) offering evidence that a good choice in outfall locations will reduce the threat to corals; and importantly (4) presenting the results in a way that enhanced understanding by nontechnical reef managers. This final result was achieved by creating movies of sediment movement that clearly demonstrated the complex hydrodynamic processes involved with near-coastal water currents. Specific model results showed: (1) that a more seaward outfall increases effluent dispersal away from sensitive areas; (2) the highest concentrations of effluent over sensitive sites occur during no wind and neap tide conditions; and (3) prevailing southeast winds advect effluent offshore, away from sensitive sites.  相似文献   
105.
Linear polyurethanes (PUs) were prepared in solution in two steps. In the first step, toluene‐diisocyanate (TDI) 80:20 (T) was reacted with a short‐chain poly(oxypropylene) diol (V) to obtain prepolymers characterized by various ratios of R = [T]°/[V]°. In the second step, the prepolymers were reacted with the extender 1,4‐cyclohexanedimethanol (E) with various extension ratios RE = (R ? 1)[V]°/[E]°. The PU properties were analyzed by various techniques. In particular, the molecular weights determined by gel permeation chromatography (GPC), the thermal properties such as glass transition temperature Tg and specific heat variation ΔCp measured by differential scanning calorimetry (DSC), the chemical composition of the PUs and the various types of hydrogen bonds present in the polymers evidenced by Fourier‐transform infrared (FTIR) spectroscopy, the monophasic structure evidenced by small‐angle X‐ray scattering (SAXS), and the existence of only one Tg confirmed that these PUs were linear, amorphous and monophasic. Positron annihilation lifetime spectroscopy (PALS) analysis showed that the mean volume of the nanoholes increased with increasing temperature, but was not dependent on the composition, as expected for a monophasic system. A stoichiometric semi‐empirical model was proposed that relates the PU blocks' micro‐composition to the R and RE macro‐parameters, chosen for the synthesis. The polymer assumes various expressions of the general formula X? [(TV)k? (TE)n]m? X for different values of the R and RE ratios. The micro‐parameters k and m have a direct connection with the experimental mean molecular weights of the prepolymer and the polymer, respectively: n depends only on R. The model could foresee the density of hydrogen bonds and distinguished the bonds connected to either V or E, which could be shown by FTIR analysis. This paper shows that, when using stereo‐irregular diols and blends of 2,4‐ and 2,6‐TDI, non‐stereoregular PUs are obtained. If low‐molecular‐weight diols are used and R < 3.3, it is quite improbable that the PU blocks separate into macrophases and therefore monophasic amorphous PUs are obtained. Monophasic PUs can be useful for applications such as in the field of membrane gas and vapour separation. Copyright © 2005 Society of Chemical Industry  相似文献   
106.
Summary The concentration of Cd, Hg and Pb in the soft part of mussels has been studied by means of bi-and multi-variate statistical approaches. In particular, the principal component analysis has been applied to study the association among these toxic metals in mussels sampled from the gulf of Trieste, which is a critical area as far as mercury pollution is concerned.
Mehrdimensionale Analyse der Daten einiger xenobiotischer Spurenmetalle in Miesmuscheln aus dem Golf von Triest
Zusammenfassung Der Gehalt von Cd, Hg und Pb in Miesmuschelfleisch wurde nach einer statistischen mehrdimensionalen Analyse untersucht. Besonders wurde die Hauptkomponentenanalyse zum Studium der Assoziationen dieser toxischen Metalle in Miesmuscheln angewandt. Die Miesmuschelproben stammten aus dem Golf von Triest, ein kritisches Gebiet für Quecksilberverunreinigungen.
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107.
108.
Describes the Family Studies Program, which has a 2-phased clinical practica format that combines theory and practice. The format is not fixed but will change as knowledge in the field increases. (3 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
109.
In this work, the Hertz vector potential method was used to obtain the dyadic Green’s function components for frequency selective surfaces (FSS) on an anisotropic layer. The considered structures are composed by periodic arrays of conducting crossed dipole and rectangular patch elements. Results of reflected power were obtained by using the moment method. Curves for the reflected power versus frequency are presented as function of the structural parameters, assuming x, y, and z orientation for the optical axis in the anisotropic substrate.  相似文献   
110.
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