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101.
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Summary We report the synthesis, stereochemistry and preliminary pharmacological evaluation of DCN 203-922, a novel ergot alkaloid of the cyclol type, which contains in its peptide moiety the uncommon amino acid L-allo-isoleucine.Part of this paper was reported by this author at the Herbstversammlung der Schweizerischen Chemischen Gesellschaft, Bern, in October 1986.  相似文献   
103.
Summary Substitution of arginine for glutamine in the 4-position of a vasopressin V1 antagonist has been reported to turn it into an agonist. We resynthesized this 4-arginine analog and synthesized additional cyclic and linear vasopressin antagonists containing a 4-arginine. The presence of a 4-arginine in the resynthesized and new analogs had relatively minor effects on their antivasopressin V1 and V2 antagonistic potencies.  相似文献   
104.
In order to obtain a radioimmunoassay (RIA) technique for the measurement of human plasma myeloperoxidase (MPO), we purified the enzyme from polymorphonuclear granulocytes (neutrophils), and compared three methods of labeling it with125Iodine: chloramine T, lactoperoxidase, and an original technique of self labeling based on the ability of the enzyme to oxidize and bind125I in the presence of H2O2. The chloramine T technique produced a degraded protein, as well shown by a high non-specific binding of tracer to antibody. The lactoperoxidase technique did not succeed in labeling MPO with an adequate specific activity. In contrast, the self-labeling method gave a stable tracer with a specific activity of 23 Ci/gmg MPO (85 MBq), a satisfactory level of immunoreactivity, and a low-specific binding (3%). After labeling, purification of tracer was achieved by gel filtration chromatography in phosphate buffer (0.05 M; pH7) to which 0.1% poly-L-lysine was added. The labeled molecule remained stable for 40 days and could be used for RIA with a polyclonal antibody raised in rabbits.  相似文献   
105.
The histamine content of rat peritoneal fluid cells is doubled within 20 min by 0.5 microgram/ml of compound 48/80. Histamine catabolism inhibitors do not reproduce this effect; cells pre-incubated with alpha-fluoromethylhistidine are unresponsive to compound 48/80 which therefore activates pre-formed histidine decarboxylase rather than 'inducing' it. Non-mast cells showed no change after treatment with compound 48/80.  相似文献   
106.
Summary Plasma membrane sheets prepared by zonal centrifugation of a premicrosomal pellet obtained from a rat liver homogenate are devoid of HCO 3 -ATPase activity. Since the microsomal fraction is also lacking in this ATPase activity, it can be concluded that the HCO 3 -ATPase is not involved in the secretion of HCO 3 into bile. Acknowledgments. This investigation was supported in part by grants No. DE-02600 and AM 80686 from the United States Public Health Service. The A-XII zonal rotor is used under subcontract No. 3796 with the Union Carbide Corporation.  相似文献   
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We look into the interaction of Google's search queries and several aspects of international equity markets. Using a novel methodology for selecting words and a vector autoregressive modeling approach, we study whether the search queries of finance‐related words can have an impact on returns, volatility of returns and traded volume in four different English‐speaking countries. We identify several words whose search frequency is associated with changes in the dependent variables. In particular, we find that increases in search queries including the word stock predict increased volatility and decreased index returns over the next week. On top of that, we investigate the performance of a market‐timing strategy based on the search frequency of this word and benchmark it against random words from the Word‐Net database and a naive buy‐and‐hold strategy. The results of this empirical application are positive and particularly stronger during the global crisis of 2009. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
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