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31.
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   
32.
B Clarke 《Nature》1970,228(5267):159-160
  相似文献   
33.
Hominoid tali from East Africa   总被引:1,自引:0,他引:1  
M H Day  B A Wood 《Nature》1969,222(5193):591-592
  相似文献   
34.
Permeability of premature eggs from Drosophila collected with the 'ovitron'   总被引:3,自引:0,他引:3  
S B Yoon  A S Fox 《Nature》1965,206(987):910-913
  相似文献   
35.
Genetics of the alkaline phosphatase polymorphism of the human placenta   总被引:27,自引:0,他引:27  
E B Robson  H Harris 《Nature》1965,207(5003):1257-1259
  相似文献   
36.
Summary The tricyclic anti-calmodulin drug trifluoperazine (TFP) inhibited growth and motility of epimastigotes ofTrypanosoma cruzi, at concentrations lower than 100 M, and motility and infectivity of the bloodstream trypomastigote form at 200 M. Electron microscopy of TFP-treated epimastigotes showed that the major effect was at the mitochondrial level, with gross swelling and disorganization. The oligomycin-sensitive, mitochondrial ATPase was completely inhibited by 20 M TFP, and the same drug concentration caused a 60% decrease in intracellular ATP content. The results suggest that the trypanocidal effect of TFP may be related more to mitochondrial damage than to the well-known anticalmodulin effect of the drug.  相似文献   
37.
38.
Summary The in vitro absorption of calcium from the duodenum was significantly less in a group of rats fed on a wheat diet than in a group fed a wheat and Bengal gram (7030) diet.  相似文献   
39.
Summary Metabolism of 26-hydroxycholesterol to 3-hydroxychol-5-en-24-oic acid and other C24-bile acids has been expected to occur by way of 3-hydroxycholest-5-en-26-oic acid in studies in vitro. 3-Hydroxycholest-5-en-26-oic acid was infused intravenously into bile fistula hamsters and the following C24-bile acids were identified: 3-hydroxychol-5-en-24-oic acid, lithocholic acid, chenodeoxycholic acid, and a small amount of cholic acid.  相似文献   
40.
Bryozoans are common, often abundant, sessile, colonial invertebrates of freshwaters. By reviewing what is known of their general ecology and considering in further detail the population biology of specific groups, we provide evidence that 1) populations are locally ephemeral and regional persistence is attained via a dynamic equilibrium between dispersal and colonization, and 2) sex may often be infrequent and a high degree of clonality obtains at both local and regional scales. On the basis of these characteristics we discuss how the group offers exceptional opportunities for investigating a number of fundamentally important ecological and evolutionary questions.The highly curious modification of the Molluscan type which the Polyzoa [=Bryozoa] present... the great beauty of their forms, and the facility with which they can in general be observed in a living state, cannot but render them special favorites for every lover of Nature; and for the more profound student must confer on them a peculiar significance, and invest their study with a scientific interest which is scarcely surpassed by that of any other group of animals.... (Allman 1856)  相似文献   
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