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Each of 571 smokers selected one of three methods of smoking cessation: group therapy, individual counseling, and hypnosis. One-year results suggest little difference between the three methods in producing ex-smokers. All methods produced an average success rate of approximately 20%. It should be noted, however, that with all types of verbal or verbally related therapy it is not known precisely how these techniques work or whether the outcomes are really a function of what is put into the therapy by the treatment agent and/or the recipient. It was generally found that younger, more educated smokers chose hypnosis; older, more educated smokers chose group therapy; and older, less-formally educated smokers chose individual counseling while the youngest and generally less educated smokers chose to become nonattenders and not take part in therapy. These results have important implications for designing optimal treatment programs which will be acceptable and effective for the greatest number of smokers.  相似文献   
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A gas-liquid chromatographic (GLC) method has been developed for monitoring the metabolic reduction of acetophenone oxime or oxidative metabolism of the corresponding amine, alpha-methylbenzylamine in liver homogenates. The oxime, amine, n-hydroxy-alpha-methylbenzylamine and acetophenone are quantitatively determined after GLC separation of components with temperature programming on an SP-2401-DB-coated column. The first three compounds were silylated with N,O-bis(trimethylsilyl)-acetamide prior to chromatographic analysis to enhance the stability and improve the chromatographic properties of these components. The effluent gas was monitored with flame ionization detection, and permitted quantitation of components at sub-microgram/ml levels with reproducibility between injections of +/-2%. The optimal composition of enantiomeric mixtures of (R,S)-alpha-methylbenzylamines formed during metabolic reduction of acetophenone oximes were determined by conversion to diastereomeric amides and subsequent GLC analysis.  相似文献   
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The stability of soluble immune complexes was investigated after isolation by gel filtration and sucrose gradient ultracentrifugation. Soluble immune complexes were formed between specific goat anti-dinitrophenol (DNP) antibodies and DNP conjugated to a large (19 S) carrier, namely bovine thyroglobulin. The composition and molecular weight of these complexes were determined by ultracentrifugation on calibrated sucrose density gradients and the use of different isotopic markers for antigen and antibody. A good separation of immune complexes containing one, two, or three antigen molecules per complex was obtained by ultracentrifugation while gel filtration was less effective. Ultracentrifugational analysis of fractions isolated by these two procedures showed that large immune complexes containing more than one antigen were relatively labile, whereas small immune complexes containing one antigen were stable. The stability of large immune complexes was dependent on dilution. Because dilution affects the size and composition of soluble immune complexes, it is important to emphasize that for the investigation of a causal relationship between the biological properties and the size and composition of immune complexes, analysis of the immune complexes should be performed in the same dilutions in which they will be used experimentally.  相似文献   
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Rat adrenal cortex contains a protein(s) that binds pregnenolone with high affinity. This binding, demonstrated by gel filtration and by a dextran-coated charcoal method, was associated with the cytosol and with fractions solubilized by sonication from the mitochondria and microsomes. The binding of pregnenolone was saturable and was inhibited by mercurials and proteolytic enzymes. Pregnenolone-binding was not influenced by the presence of progesterone, deoxycorticosterone, corticosterone or aldosterone, but was inhibited by steroids with a 3beta-hydroxy-5-ene structure similar to pregnenolone, and by hydroxymethylene steroid and cyanoketone. We suggest that this protein is involved in the intracellular transport and retention of pregnenolone within adrenal cortical cells.  相似文献   
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