摘要:

AbstractInconceivable as it is, it has been proved that animals can survive after having had their blood massively or even totally replaced by emulsions of perfluorinated compounds in salines. “Bloodles” rats charged with an emulsion of perfluorotri‐n‐butylamine survived a five hour period in an atmosphere containing 50% oxygen and 50% carbon monoxide,i.e.in conditions where the transport of oxygen by the red cells is entirely blocked. This review discusses: (1) the experiments which have demonstrated the capability of blood substitutes based on perfluorinated compounds to sustain life; (2) the characteristics and preparation of the relevant perfluoro compounds and the production and handling of their emulsions; (3) their “physiology”,i.e.toxicity, life‐span in the blood‐stream, effect on the organs and their functions, and excretion properties. Obstacles remaining to be overcome in order to provide a safe blood substitute for medical practice include the availability of numerous series of well‐defined pure and inert perfluorinated chemicals, the production of stable emulsions, the optimization of fluid balance, and the attainment of reasonable excretion rates. The accent is placed upon the role of the chemist in the progress

ISSN:0570-0833    

DOI:10.1002/anie.197806213

出版商:Hüthig&Wepf Verlag    

年代:1978

数据来源: WILEY

摘要:

AbstractPhytoalexins are defense substances with antimicrobial properties which are produced by plants after infection. They include various groups of natural substances (e.g.isoflavonoids, terpenoids, polyacetylenes and dihydrophenanthrenes). Induction of phytoalexin formation can be caused not only by living microorganisms but also by products of microbial origin (elicitors) or by stress treatment (cold, UV light). The elicitor from the mycelial walls of the fungusPhytophthora megaspermavar.sojae(Pms) is a β‐1,3‐glucan with branches at C‐6. In some cases the basic features of the biosynthesis of the phytoalexins are known. The activity of the enzymes involved in phytoalexin biosynthesis is increased by the action of the elicitor on plant tissues. The ability of some microorganisms to chemically modify the phytoalexins may be related to their pathogenicity. The role of phytoalexins as defense substances is not yet fully

ISSN:0570-0833    

DOI:10.1002/anie.197806351

出版商:Hüthig&Wepf Verlag    

年代:1978

数据来源: WILEY

摘要:

AbstractAt the start of protein biosynthesis the amino acids are chemically activated by esterification with transfer ribonucleic acids bearing the appropriate anticodons. The esterification is catalyzed with an exceptionally high specificity by aminoacyl‐tRNA synthetases. Current knowledge of the structural properties of the reactants, the course of the reaction, and the reasons for its specificity are summarize

ISSN:0570-0833    

DOI:10.1002/anie.197806481

出版商:Hüthig&Wepf Verlag    

年代:1978

数据来源: WILEY

摘要:

AbstractThe present‐day position in the field of polymeric catalysts is outlined. The following selected groups of polymeric catalysts are discussed: synthetic hydrolases, immobilized enzymes, phase‐transfer catalysts, nucleophilically active bases, polymers with conjugated π‐systems, photosensitizers, polymers as carriers for catalytically active metals or ions, and immobilized homogeneous catalysts. Polymeric catalysts have the following valuable properties: insoluble polymeric catalysts are readily separable from reaction solutions and can often be re‐used without loss of activity; a hydrophobic matrix protects the organometallic active center from deactivation by oxygen and water; by fixation of finely divided metals on an ion exchanger, multistage reactions may be effected successively in one reactor. Polymeric carriers may influence the catalytic properties; for example, in the case of immobilized enzymes on polyionic carriers the pH of the activity maximum may be

ISSN:0570-0833    

DOI:10.1002/anie.197806571

出版商:Hüthig&Wepf Verlag    

年代:1978

数据来源: WILEY

摘要:

AbstractThe tradition of mutual trust between science and the public appears to have been broken in recent years. It is necessary to define the boundaries of science and to reflect upon the responsibility of the scientist.

ISSN:0570-0833    

DOI:10.1002/anie.197806701

出版商:Hüthig&Wepf Verlag    

年代:1978

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.197806731

出版商:Hüthig&Wepf Verlag    

年代:1978

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.197806742

出版商:Hüthig&Wepf Verlag    

年代:1978

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.197806751

出版商:Hüthig&Wepf Verlag    

年代:1978

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.197806762

出版商:Hüthig&Wepf Verlag    

年代:1978

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.197806771

出版商:Hüthig&Wepf Verlag    

年代:1978

数据来源: WILEY