ISSN:0250-6807    

DOI:10.1159/000175749

出版商:S. Karger AG    

年代:1977

数据来源: Karger

摘要:

Cholesterol is distributed in different body pools. Input in these pools takes place through absorption of dietary cholesterol and endogenous synthesis. Absorption is limited in man. Endogenous synthesis is under negative feedback control, but its physiological relevance in man is less well established. Recent studies in familial hypercholesterolemia have shown a slower catabolism of low density hpoproteins (LDL) and an overproduction of apoprotein B. It seems that also the synthesis of the apoprotein B is controlled by a feedback mechanism. Overall concentration of lipids and hpoproteins in plasma is determined by the interaction between several genetic and dietary feedback mechanisms.

ISSN:0250-6807    

DOI:10.1159/000175750

出版商:S. Karger AG    

年代:1977

数据来源: Karger

摘要:

Allopurinol-induced orotaciduria is reduced by dietary ribonucleic acid (RNA), RNA hydrolysate and different nucleotides. These findings are compatible with feedback regulation of pyrimidine biosynthesis by dietary nucleotides. Serum uric acid and urinary uric acid excretion on a purine-free isoenergetic diet reach a minimum after about 10 days and remain constant thereafter. When purines from different biochemical sources are added to such a diet there is always a linear relationship between dietary purines and serum uric acid level and urinary uric acid excretion. The findings suggest that dietary purines play a minor role if any in the regulation of purine biosynthesis in man.

ISSN:0250-6807    

DOI:10.1159/000175751

出版商:S. Karger AG    

年代:1977

数据来源: Karger

摘要:

Inborn errors of metabolism affect the metabolism of 7 out of 8 essential amino acids and a number of non-essential ones. Dietary treatment has been applied with varying success. The wide variations in the severity of symptoms in this group of diseases are discussed. Dietary treatment opens the possibility to collect information about the minimal requirements of most essential amino acids. These requirements are likely to be still lower than those mentioned in the WHO Report No. 522, 1973. Children who for years have lived on one of these restricted diets, provide the possibility to compare the effect of such a diet on their nutritional status with that of children living on a normal diet.

ISSN:0250-6807    

DOI:10.1159/000175752

出版商:S. Karger AG    

年代:1977

数据来源: Karger

摘要:

Several primarily inherited disturbances of minerals and trace elements have been discovered within the last 20 years. Secondary disturbances of selenium and zinc induced by dietetic treatment of inborn errors of metabolism and by parenteral nutrition also came to our knowledge recently. Two main types of chronic or primary hypomagnesaemia are known which are caused either by impaired intestinal absorption or by false magnesium handling by the kidneys. In acrodermatitis enteropathica, an autosomal-recessive inherited disease leading to characteristic skin lesions, alopecia and dystrophy, low zinc concentrations of serum, urine and hair are measured. The intestinal absorption of zinc is reduced. In copper metabolism two inherited diseases are known with low serum and usually caerulosplasmin concentrations. In Menkes’ steely hair syndrome (trichopoliodystrophy) an intestinal net malabsorption of copper exists, whereas in Wilson’s disease the copper contents of several organs are increa

ISSN:0250-6807    

DOI:10.1159/000175753

出版商:S. Karger AG    

年代:1977

数据来源: Karger

摘要:

In coeliac disease there is an abnormality of the intestinal mucosa which is caused by ingesting gluten. The intestinal lesion affects predominantly the proximal small intestine and the ileum is either normal or less severely involved than the jejunum. In some cases adaptive changes occur in the ileum, producing enhanced absorption in that region when there is malabsorption in the jejunum. The characteristic absorptive abnormality in coeliac disease is therefore jejunal malabsorption and Heal hyperabsorption. When such a situation develops it is possible that an individual with a flat jejunal mucosa may develop no symptoms of the disease, since the adaptive changes in the ileum compensate for the jejunal lesion. This may explain why in Western society there are probably more cases of coeliac disease undiagnosed in the community than have been treated by their doctors. The basic lesion in coeliac disease appears to be genetically determined and it is likely to be a failure to clear antigen which normally enters the lamina propria of the gut resulting in the formation of immune complexes with complement fixation at gut level.

ISSN:0250-6807    

DOI:10.1159/000175754

出版商:S. Karger AG    

年代:1977

数据来源: Karger

摘要:

Animals undernourished before birth and therefore born small are not particularly hungry and do not take enough food to enable them to catch up their larger fellows after birth even when there is a plentiful supply of milk. Animals and children undernourished after birth are very hungry and they eat far more per unit body weight than well-nourished individuals as soon as food is available. They gain weight rapidly for a time, and the ‘catch-up’ may or may not be complete depending on the severity and duration of the undernutrition. This difference in response to rehabilitation after undernutrition at different ages is attributed to the stage of development the appetite centres in the hypothalamus have reached when the undernutrition was imposed. Whether the animals undernourished after birth catch up in weight or not, they deposit more fat than normal, suggesting that appetite has outrun the ability to lay down lean tis

ISSN:0250-6807    

DOI:10.1159/000175755

出版商:S. Karger AG    

年代:1977

数据来源: Karger

摘要:

Attention was paid to the levels of importance of maintenance, protein and fat deposition in growing monogastrics. Some information was presented on the composition of their daily gain. Theoretical efficiency values of fat synthesis were derived from biochemical information and compared with those found in balance trials. Factors determining maintenance needs including thermoregulation and physical activity were discussed. Some aspects of energy metabolism and regulation of body fat deposition and mobilization were described including the processes of hyperplasia and hypertrophy. Finally, the role of fat as a well-regulated, rapidly adaptable buffer within the mono-gastric’s total metabolism was emphasize

ISSN:0250-6807    

DOI:10.1159/000175756

出版商:S. Karger AG    

年代:1977

数据来源: Karger

摘要:

Methods of determining protein and energy metabolism in farm animals and man are discussed. From experiments with growing pigs a curve for maximum nitrogen retention has been established and expressed as a quadratic function of metabolic live weight (kg0.75). From experiments with growing pigs kept on protein with low biological value and from experiments with low energy level the nitrogen retention is compared with the maximum nitrogen curve and the results are discussed in relation to human nutrition. The comparatively high cost of protein deposition found in experiments with growing farm animals is discussed.

ISSN:0250-6807    

DOI:10.1159/000175757

出版商:S. Karger AG    

年代:1977

数据来源: Karger

摘要:

The term ‘essentiality’ of trace elements is interpreted. The major human diseases due to trace element deficiency (Fe, Cu, Zn, Cr) are briefly considered. In growing animals the first clinical deficiency symptom most often is a growth retardation. In order to diagnose a deficient situation before the manifestation of clinical symptoms, model studies with growing animals are presented to show criteria that respond sensitively even to suboptimum intake of trace elements (Zn, Cu, Fe, Ni). Activity measurements of enzymes and hormones are found suitable. During the phase of reproduction, which is closely associated with growth, the trace element concentration in milk may provide an additional diagnostic means. In conclusion, the problems of diagnosing the supply status are discussed. A possibility for determination of the trace element requirement is indica

ISSN:0250-6807    

DOI:10.1159/000175758

出版商:S. Karger AG    

年代:1977

数据来源: Karger