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11.
The 13C NMR spectra of geosmin, selina-4(14),7(11)-diene-99-ol and two dihydroeudesmol isomers have been obtained and the individual resonances assigned. Several different empirical correlations developed by others have been combined in simple calculations to predict chemical shift values for sesquiterpenols of the eudesmane group. 相似文献
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Gametic chromosome numbers are reported for 27 collections representing the four species of the Lobelia tupa complex (Campanulaceae, Lobelioideae) in Chile; all are n = 21. This represents the first report of chromosome numbers for L. bridgesii Hook. & Arn., L. excelsa Bonpl., and L. polyphylla Hook. & Arn., and confirms previous reports of this number in L. tupa L. As the basic chromosome number of Lobelioideae is x = 7, these species are interpreted as hexaploids. Higher polyploids are extremely rare among Lobelioideae; most of those previously reported have been either sporadic individuals or populations within an otherwise diploid or tetraploid species, or occasional species within an otherwise diploid and tetraploid lineage. This is the first report of an entire complex of lobelioid species that is uniformly hexaploid. This suggests that the Chilean endemics are relatively derived within Lobelia, and offers some support for the monophyly of the complex. 相似文献
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Nancy Scheper-Hughes 《Culture, medicine and psychiatry》1987,11(1):53-78
The deinstitutionalization of psychiatric patients is a deeply cultural as well as political task. It entails the sharing of responsibility for human distress with family and community. Consequently, the locus of social control has also shifted from psychiatric and medical expertise to community and legal institutions. Diagnosis and treatment models must be more compatible with lay explanatory models. This paper explores the various meanings of going mental and being mental in the white, working class, ethnic neighborhood of South Boston. The data are extracted from a study of the impact of deinstitutionalization on a cohort of middle-aged, psychiatric patients discharged from Boston State Hospital in the attempt to return them to community living. Individual, family, and community responses to, and interpretations of, the symptoms of mental distress are discussed. The study indicates that even seriously disturbed individuals are sensitive to cultural meanings and social cues regarding the perception, expression, and content of psychiatric episodes. While madness invariably disenfranchises, it does not necessarily deculturate the individual. 相似文献
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Characterization and in Vivo Cloning of prlC, a Suppressor of Signal Sequence Mutations in Escherichia coli K12 总被引:19,自引:1,他引:18 下载免费PDF全文
The prlC gene of E. coli was originally identified as an allele, prlC1, which suppresses certain signal sequence mutations in the genes for several exported proteins. We have isolated six new alleles of prlC that also confer this phenotype. These mutations can be placed into three classes based on the degree to which they suppress the lamB signal sequence deletion, lamBs78. Genetic mapping reveals that the physical location of the mutations in prlC correlates with the strength of the suppression, suggesting that different regions of the gene can be altered to yield a suppressor phenotype. We also describe an in vivo cloning procedure using lambda placMu9H. The procedure relies on transposition and illegitimate recombination to generate a specialized transducing phage that carries prlC1. This method should be applicable to any gene for which there is a mutant phenotype. 相似文献
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Zenon Steplewski K. Ann Jeglum Carlos Rosales Nancy Weintraub 《Cancer immunology, immunotherapy : CII》1987,24(3):197-201
Summary Lymphoma in dogs resembles human non-Hodgkin's lymphoma in pathological presentation, immunophenotype, and response to therapy, thus representing a good model for comparative studies with human disease. Monoclonal antibodies (MAbs) were derived from mice immunized with a dog lymphoma cell line. Three MAbs were selected for further application in immunophenotyping and immunotherapy. The binding specificities, antigen characterization, and isotypes for these MAbs are described.Supported by NCI grant CA-10815 相似文献
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Evangelia G. Kranias Ramesh C. Gupta Gyorgyi Jakab Hae Won Kim Nancy A. E. Steenaart Stephen T. Rapundalo 《Molecular and cellular biochemistry》1988,82(1-2):37-44
Summary Canine cardiac sarcoplasmic reticulum is phosphorylated by adenosine 3,5-monophosphate (cAMP)-dependent and by calcium · calmodulin-dependent protein kinases on a 27 000 proteolipid, called phospholamban. Both types of phosphorylation are associated with an increase in the initial rates of Ca2+ transport by SR vesicles which reflects an increased turnover of elementary steps of the calcium ATPase reaction sequence. The stimulatory effects of the protein kinases on the calcium pump may be reversed by an endogenous protein phosphatase, which can dephosphorylate both the CAMP-dependent and the calcium · calmodulin-dependent sites on phospholamban. Thus, the calcium pump in cardiac sarcoplasmic reticulum appears to be under reversible regulation mediated by protein kinases and protein phosphatases. 相似文献