摘要:

SummaryLipid particles of soya bean oil emulsions prepared with various emulsifying agents (egg yolk phosphatides, acetylated monoglycerides and poly‐oxypropylene‐polyoxyethylene polymers) were examined in sections of osmium‐fixed pellets. The mean particle size fell within the range of 0·3 to 0·8 μm for all but one emulsion and did not appear to be related to the emulsifying system used.Morphologically, particles of emulsions containing phosphatides were coated by an electron dense granular surface layer which was absent with the other emulsifiers. The presence of drugs in the oil phase did not alter the appearance of the lipid particles.

ISSN:0004-945X    

DOI:10.1038/icb.1974.68

出版商:Nature Publishing Group    

年代:1974

数据来源: WILEY

摘要:

SummaryBarbiturates dissolved in lipid emulsions are more effective than aqueous preparations of the drugs for intravenous use. To test whether this effect might be related to adhesion of lipid particles to cerebral endothelium, various emulsions containing secobarbital or thiopental were injected intravenously into mice. Blood vessels of the brain and of the lung of animals killed at 5 minutes, 20 minutes and 24 hours were examined by electron microscopy. Though lipid particles were sometimes in contact with the vessel wall, preferential localization or sticking to the endothelium was not observed. Side effects which related to emulsifying agents were platelet aggregation and fat emboli in the lungs.

ISSN:0004-945X    

DOI:10.1038/icb.1974.69

出版商:Nature Publishing Group    

年代:1974

数据来源: WILEY

摘要:

SummaryStudies were made on the origin and mechanism of transfer of IgG1, IgG2, IgA and IgM into the secretion of isolated loops of jejunum of unanaesthetized sheep. IgA was the major immunoglobulin in intestinal secretion, although considerable quantities of IgG1and IgG2were also present. Secretion: serum radioactivity ratios for IgG1and IgG2were similar, indicating that they were transferred into intestinal secretion with equal facility. Specific radioactivities of the various immunoglobulins in serum and secretion were compared and the results suggested that all the IgG2and most of the IgG1were derived from blood plasma, whereas only a trivial amount of the IgA was plasma‐derived. The slow equilibration of IgM, together with its relatively short biological ‘half‐life', prevented accurate assessment of plasma contribution of this immunoglobulin.

ISSN:0004-945X    

DOI:10.1038/icb.1974.70

出版商:Nature Publishing Group    

年代:1974

数据来源: WILEY

摘要:

SummaryIn non‐pregnant adult sheep biological ‘half‐lives’ of IgG1and IgG2were approximately 8 days with those for lambs slightly less than 7 days. In contrast, in late pregnant ewes forming colostrum the ‘half‐life’ of IgG1was only 3·7 days. This value was significantly less (P<0·01) than for IgG2and less (P<0·001) than the value for IgG1in non‐pregnant animals.

ISSN:0004-945X    

DOI:10.1038/icb.1974.71

出版商:Nature Publishing Group    

年代:1974

数据来源: WILEY