摘要:

AbstractThe mean life span has plateaued in the developed countries at around 70 years. Future substantial increases in the mean life span are apt to be due to inhibition of the process(es) involved in aging. One potentially practical means of inhibiting the rate of human aging is based on the hypothesis that free radical reactions play a significant role in the degradation of biological systems. Experiments based on this hypothesis have been encouraging. For example, several inhibitors of free radical reactions have been found to increase the mean life span of mice when added to the daily diet; 2‐mercaptoethylamine and butylated hydroxytoluene were the most effective. Likewise, decreasing the amount and degree of unsaturation of the dietary fat of female C3H mice resulted in a decrease in the mortality rate. The probable role of free radical reactions in the pathogenesis of four age‐associated diseases—cancer, atherosclerosis, hypertension and amyloidosis—is discussed.It is suggested that the addition of one or more inhibitors of free radical reactions to nutritionally adequate and acceptable natural diets selected to minimize the intake of substances that might participate in random endogenous free radical reactions, may increase the average life span of man by five or more years, with accompanying increases in the years of useful, healt

ISSN:0002-8614    

DOI:10.1111/j.1532-5415.1969.tb02286.x

年代:1969

数据来源: WILEY

摘要:

AbstractThe individual begins with an event having the characteristics of a launching. An analysis of the decline in basal metabolic rate and percentage of total body water, as examples of the continuous processes of senescence, upholds this concept. The highest functional values are present at or shortly after conception, but they decline continuously throughout life.

ISSN:0002-8614    

DOI:10.1111/j.1532-5415.1969.tb02287.x

年代:1969

数据来源: WILEY

摘要:

AbstractA study was made of the effects of testosterone, estradiol, ACTH, insulin, epinephrine andl‐thyroxine on a microsomal preparation of female rat liver esterifying enzyme and cholesterol plus palmitic, oleic and linoleic acids. In the doses used, these hormones modified the rate of ester synthesis. Further experiments showed that low doses of androgen or estrogen had a stimulating effect whereas high doses had an inhibitory effect.On the basis of our findings and a review of the literature, it is concluded that the concentration of cholesterol or its esters in the plasma at any given time is determined by the net rate: 1) of absorption, 2) synthesis, 3) transport and lipoprotein binding, and 4) fecal excretion and partial re‐absorption following oxidative degradation of cholesterol to bile acids.The turnover rate of free cholesterol is far more rapid than that of the ester. Also, the degree of unsaturation of the ester influences the rate of turnover. Mono‐unsaturated esters have the highest turnover rate. Lipoprotein binding in the very‐low‐density fraction is dependent upon diet; the more dense lipoproteins (>1.061–1.21) are thought to be partially under genetic control.Hormones act at three levels: 1) biosynthesis, 2) compartmentalization and transport (binding), and 3) excretion. The first two mechanisms may be involved with androgens, estrogens and insulin.The atherosclerotic process involves many physicochemical factors. Diet and hormones modify the ester fraction. They also change the endogenous synthesis of cholesterol from acetate or mevalonate. Apparently the composition of the ester plays an important role in the deposition of cholesterol and its esters in sites of p

ISSN:0002-8614    

DOI:10.1111/j.1532-5415.1969.tb02288.x

年代:1969

数据来源: WILEY

摘要:

AbstractA reliable test for the early detection of cancer is much to be desired and has long been sought. The Intradermal Cancer Test (ICT) is based upon immunological principles, and according to the author's findings, is not influenced by certain non‐neoplastic diseases or physiological changes. The author first reported his work in 1955, and in the ensuing years has accumulated data on 995 subjects. He concludes that the test can detect early cancer, and that it is specific, reproducible and practical. The data are presented here with the hope that other research workers in this field will be encouraged to inquire further into the methods outlined in this articl

ISSN:0002-8614    

DOI:10.1111/j.1532-5415.1969.tb02289.x

年代:1969

数据来源: WILEY

摘要:

AbstractThe subject of nutrition in the aged is reviewed under the headings of requirements for calories, protein, carbohydrates, fats, minerals (calcium, phosphorus, iron and iodine), and vitamins (water‐soluble and fat‐soluble).Our knowledge of the process of aging is distinctly limited. Although many changes in body composition and functioning occur during senescence, the exact mechanisms are still unknown. Thus the matter of possible changes in the requirements for various nutrients during aging needs much more investigation. At present many of the reported findings are conflicting and controvers

ISSN:0002-8614    

DOI:10.1111/j.1532-5415.1969.tb02290.x

年代:1969

数据来源: WILEY

摘要:

AbstractData are presented on 10 cases of carcinoid tumor; 8 of the tumors were in the gastrointestinal tract and 2 in the lung. Two cases were associated with carcinoid syndrome (flushing attacks, diarrhea, bronchospasm); in one of these with marked symptoms, the 24‐hour excretion of 5 hydroxy indole acetic acid reached 107 mg.On the basis of these findings and those reported in some pertinent literature, it would seem that the carcinoid syndrome does not develop unless carcinoid products (including excessive amounts of serotonin) are discharged into the systemic circulation. These products are secreted in abnormally high proportions over normal pathways, and thus reduce the normal formation of other substances necessary for health. The question of whether all carcinoid tumors originate in the gut is still unresolve

ISSN:0002-8614    

DOI:10.1111/j.1532-5415.1969.tb02291.x

年代:1969

数据来源: WILEY