摘要:

The acid glycosaminoglycans of human mitral valves are differentiated histochemically by the critical electrolyte concentrations of alcian blue. Age- dependent changes in the composition of acid mucopolysaccharides in the ground substances of valves are investigated by histophotometric measurements between the free valve edge and the line of closure. With respect to these values, the concentration of the total acid mucopolysaccharides in mitral valves grows with aging. The first increase is seen until to the 4th decade, a second one with the 5th decade reaching its maximum in old age. Sulfomucopolysaccharides show similar variations; increasing until the 4th decade, they are followed by a slight decrease and new increasing until old age. The concentration of more alcianophilic chondroitin sulfates, however, reaches a maximum in the 4th decade, falling off in later life. No acid mucopolysaccharides of higher sulfation grade are detected in mitral valve ground substances. Hyaluronic acid represents the main part of acid mucopolysaccharides in mitral valves. With advancing age the content of hyaluronic acid grows at a rate equal to that of the total acid mucopolysaccharides and reaches its maximum concentration in the 8th and 9th decade. The chondroitin sulfates represents 20–22% of the total acid mucopolysaccharides. This ratio does not change substantially during the aging proces

ISSN:0304-324X    

DOI:10.1159/000212002

出版商:S. Karger AG    

年代:1974

数据来源: Karger

摘要:

Statistical analysis of rubella titers (values partly from the literature) reveals that about 4% of those between 16 and 30 years of age are without antibodies. Older age groups show complete immunization of all individuals. Mean rubella titers in subjects between 16 and 40 years of age are identical. A group of elderly subjects (60 years) shows decreased titers that could be statistically verified. IgG serum concentrations in individuals over 60 years are significantly elevated if compared with normal medium values. The results are discussed in view of previous studies about antibodies and IgG concentration in the aged.

ISSN:0304-324X    

DOI:10.1159/000212003

出版商:S. Karger AG    

年代:1974

数据来源: Karger

摘要:

The effects of age on the immune response were studied in highly responding and poorly responding strains of inbred rats. Changes in the immune response associated with age were found only in the highly responding strain: the antibody response fluctuated up to 10–12 weeks of age, showed no significant change up to 60 weeks of age and decreased thereafter. In addition, immunization increased the weight and the number of germinal centers in the spleen and stimulated cortical nuclear phagocytosis in the thymus. The factors influencing antibody formation at different ages appear to modulate the genetically set capability of the immune system, and they are most conspicious early and late in lif

ISSN:0304-324X    

DOI:10.1159/000212004

出版商:S. Karger AG    

年代:1974

数据来源: Karger

摘要:

The action of pyridinol carbamate (PDC) was studied in rats during chronic intoxication with β-aminopropio-nate (BAPN), and also during chronic lathyrism associated with a atherogenic diet; (1) a protective effect of PDC on the aortic wall with regard to the toxic effects of BAPN was noted; (2) PDC retards the development of elastic tissue lesions and reduces their intensity and frequency; (3) with regard to the role of PDC in the prevention of experimental atheroma, this compound has no lipid reducing action but preserves the integrity of the aortic wall and hinders the penetration of fat depots into the media which is the initial site of experimentally induced atherogenic lesions, and (4) PDC can be considered as an anti-atherogenic agent. Because of its protective action, it inhibits one of the most important factors in atherogenesis – the parietal factor. It might be active in the prevention of vascular arteriosclerosis and also aortic atheroscleros

ISSN:0304-324X    

DOI:10.1159/000212005

出版商:S. Karger AG    

年代:1974

数据来源: Karger

ISSN:0304-324X    

DOI:10.1159/000212006

出版商:S. Karger AG    

年代:1974

数据来源: Karger