摘要:

Rod-like inclusions made up of bundles of parallel fibrils (approximately 7 nm thick) are found with greater frequency in the neurone nuclei of aged than in young mice. Sometimes the fibrils are arranged in lattice formation. Circular membrane inclusions are also found within the nuclei of aged neurones. Cross-banded intranuclear inclusions are occasionally present in nuclei of old neurones.

ISSN:0304-324X    

DOI:10.1159/000211816

出版商:S. Karger AG    

年代:1971

数据来源: Karger

摘要:

The physical-chemical characteristics of intramuscular connective tissues (IMCT) collagen were studied in relation to in vitro aging.No change in the quantity of either salt- or acid-soluble tropocollagen was evident in samples stored at 4°C for 100 h. The β-subunit composition of the extracts from the 100-hour samples was, however, significantly greater, indicating that intramolecular cross-links had formed in vitro. The amino acid composition and hydrothermal shrinkage temperatures were similar in both the 0- and 100-hour samples. No change in solubility or subunit composition was evident in samples stored for 6 months at –

ISSN:0304-324X    

DOI:10.1159/000211817

出版商:S. Karger AG    

年代:1971

数据来源: Karger

摘要:

A thermal analytical method was applied to study the effect of experimental lathyrism on the composition and structural stability of aorta, tendon and hyaline cartilages of rabbits.A defect in collagen and elastin synthesis, resulting in the production of labile cross-linkages within the fibrillar protein moiety of the connective and vascular tissues of growing animals could be demonstrated. In the aorta and tendon of young rabbits glycosa4minoglycan concentration increased in the first 20 days of treatment. In the investigated tissues of adult animals β-amino-propionitrile-feeding caused no alterations

ISSN:0304-324X    

DOI:10.1159/000211818

出版商:S. Karger AG    

年代:1971

数据来源: Karger

摘要:

The authors simultaneously studied the physico-chemical properties of rat tail tendon (amount of labile hydroxyproline, changes of thermo-isometric tension) and uterine collagen (collagen content, total hydroxyproline, labile hydroxyproline ratio) during the biological ageing of control animals and experimental animals of identical age, exposed to long-lasting stressful stimulation. Similar changes to the tail tendon were found in the uterine collagen. The localisation of increased uterine collagen production under the given experimental conditions, besides the fibroblasts, was partly found in the smooth muscle cells transformed to fibroblastic direction as revealed by electron microscopic investigation of the myometrium.

ISSN:0304-324X    

DOI:10.1159/000211819

出版商:S. Karger AG    

年代:1971

数据来源: Karger

摘要:

Since improved methods make it possible to determine both elastoproteinase and elastomucase activity in crude pancreatic extracts, the effect of age on enzyme titer in the pancreas was studied in virgin Wistar rats of both sexes. In males, the elastoproteinase concentration (in elastoproteinase unit [EU] per gram acetone-dried pancreas) decreased with age over the whole period of 0–24 months; the elastomucase Em-I and Em-S concentrations (in elastomucase unit [Em-U] per gram acetone-dried pancreas) rapidly decreased with age up to 12 months (Em-S) and 18 months (Em-I), remaining nearly constant after that age period. In female rats, the elastoproteinase concentration remained constant during the 1st year of life, increased rapidly between 15 and 18 months, then decreasing to the 15-month level at an age of 27 months. The titer of both elastomucases fell during the growth of the females, remaining constant between 6 and 15 months of age and showed a rapid increase in enzyme level between 15 and 18 months. Although there was a tendency for the enzyme concentration to decrease after 18 months, the fall was not statistically significant. The data obtained with rat pancreas were compared with those for human pancreatic enzymes and for human serum ‘elastoproteinase’ reported previously. Similar age-relationships were

ISSN:0304-324X    

DOI:10.1159/000211820

出版商:S. Karger AG    

年代:1971

数据来源: Karger

摘要:

The aim of this study is to check the following 2 hypotheses: (1).Has the age factor a different influence on learning abilities and retention in normal individuals? (2). Has the age factor the same qualitative effects on learning abilities and retention as brain damage? In order to check the 1st hypothesis, the scores recorded when 2 groups of normal individuals underwent a verbal learning test were compared. Both groups were matched as far as social and cultural level was concerned; age varied from 55 to 69 within the 1st group and from 70 to 84 within the 2nd one. In order to check the 2nd hypothesis, the scores recorded when 46 brain damaged subjects underwent the same test were compared with those obtained for 46 subjects randomized in the healthy sample. Both groups were matched as far as age, sex as well as social and cultural level were concerned. In order to assess learning abilities, the subjects were asked to recall the material they had just learnt. In order to assess retention, they were asked to recall the material they had learnt 2 h beforehand. As the delayed recall is evidently dependent upon the learning process, the scores obtained after a delay were dealt with through a covariance analysis. From the results, it is possible to draw the following conclusions: (1). In normal individuals, aging involves a loss of learning abilities, but does not disturb retention. (2). In brain damaged subjects, not only learning abilities, but also retention appear to be seriously disturbed, hence the effects of age and those of brain damage are not qualitatively identical.

ISSN:0304-324X    

DOI:10.1159/000211821

出版商:S. Karger AG    

年代:1971

数据来源: Karger

ISSN:0304-324X    

DOI:10.1159/000211822

出版商:S. Karger AG    

年代:1971

数据来源: Karger

ISSN:0304-324X    

DOI:10.1159/000211823

出版商:S. Karger AG    

年代:1971

数据来源: Karger