摘要:

The specific activity of each of the two enzymes primarily concerned with the energy metabolism of flight muscle contraction was determined in male Drosophila melanogaster, from emergence through 5 weeks postemergence. Ca++-activated actomyosin ATPase activity rose rapidly from a minimum at emergence to a peak level at 4–5 days, falling gradually thereafter to a minimum level at 10–11 days postemergence, with no change thereafter. Arginine phosphokinase activity rose more gradually to a maximum at 11–12 days postemergence and then fell slowly to a minimum at 18–19 days. These data represent a sequential pattern of biochemical changes similar to those previously observed in other dipteran species, confirming the primary role of a genetic program for maturation and senescence of flight ability in holometabolous adult insects at the functional and underlying cellular, biochemical

ISSN:0304-324X    

DOI:10.1159/000212489

出版商:S. Karger AG    

年代:1981

数据来源: Karger

摘要:

The role of DNA repair in the aging process was studied using fibroblast cultures derived from rats at the beginning (3 weeks) and at the end (2 years) of their potential lifespan. The effect of treatment of the cultures with the DNA-damaging agent, ethylnitrosourea, on the integrity of the pre-existing, parental DNA and on de novo DNA synthesis was determined using the alkaline elution method. It was found that drug treatment resulted in lower levels of fragmentation of parental DNA and in decreased fractions of short daughter strands in cells derived from old relative to young animals. These results indicate an alteration of the processing of DNA damage in cells derived from aged rats.

ISSN:0304-324X    

DOI:10.1159/000212490

出版商:S. Karger AG    

年代:1981

数据来源: Karger

摘要:

The experiments were done to investigate modifications with aging in reactivity and speed of recovery of the sympathetic adrenomedullary system during psychosocial stress. Normal male volunteers were studied. Urinary adrenaline and noradrenaline, diuresis, pH and specific gravity were measured. Adrenaline and noradrenaline baseline levels were lower in the older age group. Adrenaline levels increased by the same percent during stress in the two age groups, but came back to pre-stress values more slowly in older subjects, as did blood pressure.

ISSN:0304-324X    

DOI:10.1159/000212491

出版商:S. Karger AG    

年代:1981

数据来源: Karger

摘要:

Serum chromium levels were measured in 81 subjects (56 males and 25 females) with a mean age of 54 years (range 22–91 years). The mean serum chromium level in those under the age of 60 years was 1.6 ± (SE) 0.125 ppb (30.7 ± 2.4 nmol/l) whereas in those over the age 60 years it was 1.9 ± 0.195 ppb (36.5 ± 3.7 nmol/l). There was no evidence of any change in serum chromium levels with increasing age (r = 0.0096; p > 0.1) when all the subjects were considered. However, amongst the males a small but definite increase in serum chromium from 1.5 ± 0.135 ppb (28.8 ± 2.6 nmol/l to 2.1 ± 0.25 ppb (40.6 ± 4.8 nmol/l was dem

ISSN:0304-324X    

DOI:10.1159/000212492

出版商:S. Karger AG    

年代:1981

数据来源: Karger

摘要:

A high pressure liquid chromatographic method was used to measure the serum concentrations of salicylic, salicyluric and gentisic acids in patients receiving chronic acetylsalicylic acid therapy. There was good correlation between this method and the established colorimetric assay for salicylic acid. The concentration of gentisic and salicyluric acids were increased in patients older than 60 years. No correlation was found with sex, concomitant ingestion of other drugs, serum creatinine or serum albumin.

ISSN:0304-324X    

DOI:10.1159/000212493

出版商:S. Karger AG    

年代:1981

数据来源: Karger

摘要:

3 cases of transient global amnesia (TGA) are reported. Transient ischaemia is probably the cause of the condition in the majority of cases although other mechanisms, particularly epilepsy, may be responsible in some. TGA may not be reported by the patient and may be misdiagnosed as a psychiatric disturbance. An acute confusional or delirious state can also produce an episode of amnesia with inability to remember events which occurred during the period of cerebral dysfunction. In TGA, however, there is an acute and temporary failure to record events without the evidence of more generalised dysfunction which occurs in delirium. During the 3 episodes reported here the patients were able to carry on with their everyday activities and to complete structured tasks, such as the preparation of a meal. TGA appears, at least in some individuals, to carry the prognosis of transient cerebral ischaemia.

ISSN:0304-324X    

DOI:10.1159/000212494

出版商:S. Karger AG    

年代:1981

数据来源: Karger

摘要:

Measurements of total exchangeable potassium and total exchangeable sodium, total body water and extracellular fluid volumes were made in 69 patients aged 30–90+ years, using multiple isotope techniques. The patients were not suffering from any chronic disorder or having potassium or diuretic therapy and were considered to be having a normal hospital diet. The study showed a direct correlation between potassium and age, in that total exchangeable potassium decreased as age increased. The same relation was obtained when total exchangeable potassium was related to dry body weight and fat-free body water to age. Although total exchangeable sodium diminished with increasing age, the ratio of total exchangeable potassium was approximately 1 at 30 years of age rising to approximately 2 at 90+ years of ag

ISSN:0304-324X    

DOI:10.1159/000212495

出版商:S. Karger AG    

年代:1981

数据来源: Karger

ISSN:0304-324X    

DOI:10.1159/000212496

出版商:S. Karger AG    

年代:1981

数据来源: Karger

ISSN:0304-324X    

DOI:10.1159/000212497

出版商:S. Karger AG    

年代:1981

数据来源: Karger

ISSN:0304-324X    

DOI:10.1159/000212498

出版商:S. Karger AG    

年代:1981

数据来源: Karger