摘要:

Purine ribonucleotides are degraded to uric acid by a complexly regulated metabolic pathway. Abrupt lowering of intracellular ATP, a physiological inhibitor of this pathway at normal concentrations, precipitates a cascade of nucleotide catabolism. The clinical syndrome of accelerated purine ribonucleotides catabolism, as defined by hyperuricemia, hyperuricosuria and elevated urinary oxypurines, has primary and secondary causes. Treatment of these disorders is in general directed toward reversal of the precipitating factors, inhibition of further nucleotide degradation, and stimulation of purine nucleotide and ATP formation. Careful clinical application of these principles seems indicated.

ISSN:0250-6807    

DOI:10.1159/000175474

出版商:S. Karger AG    

年代:1974

数据来源: Karger

摘要:

In 15 subjects, secretin administered intravenously increased the insulin secretion significantly as well as volume and bicarbonate content of the duodenal juice. The inhibition of the exocrine pancreas by acetazolamide did not influence the β-cytotropic effect of secretin. The loss of this effect in patients suffering from chronic pancreatic insufficiency seems, therefore, to be caused, not by the decreased volume and bicarbonate secretion, butby other unknown factors

ISSN:0250-6807    

DOI:10.1159/000175475

出版商:S. Karger AG    

年代:1974

数据来源: Karger

摘要:

Addition of oxidized linoleate to the diet of rats resulted in a decreased rate of weight gain, an increased calorie requirement for each gram of weight gained, an impairment of fat absorption and an increase in the weight and length of the small intestine. The white cell count, blood haemoglobin levels and the concentration of folic acid in serum and urine were found to be reduced. Of the two metabolically active derivatives of folic acid examined in urine specimens, folinic acid levels showed a significant reduction but not those of N-10-formyltetrahydrofolic acid. Administration of folic acid to these animals resulted in a reticulocyte response and return of the white cell count to normal values.

ISSN:0250-6807    

DOI:10.1159/000175476

出版商:S. Karger AG    

年代:1974

数据来源: Karger

摘要:

The present study was performed to measure the effect of increasing amounts of ascorbic acid on the absorption of 5 mg iron in a maize meal. 30 normal subjects were served two maize meals, one of them with ascorbic acid at different dose levels. At the dose level of 200 mg ascorbic acid there was a sixfold increase in iron absorption. Still at the dose level of 25 mg, the iron absorption was significantly increased. The results of the study thus indicates that supplementation with ascorbic acid might be an alternative to iron fortification to increas dietary iron absorption.

ISSN:0250-6807    

DOI:10.1159/000175477

出版商:S. Karger AG    

年代:1974

数据来源: Karger

摘要:

Bran is known to reduce iron absorption. There is, however, no information on the relationship between the amount of bran added and the decrease in iron absorption. In the present study a comparison was made of the iron absorption from a white wheat bread and a bread baked with different amounts of bran added (from 10 to 0.3%). There was a decrease in iron absorption from rolls baked with added bran in amounts equal to and greater than 3.3 %. A significant linear relationship was found between the ratio of absorption with/without added bran and the log amount of bran added. From the relationship observed it is concluded that addition of approximately 7% of bran to wheat bread decreases ironabsorption by a factor of two. It is considered reasonable to ascribe the marked reductionin iron absorption to the content of phytate in bran.

ISSN:0250-6807    

DOI:10.1159/000175478

出版商:S. Karger AG    

年代:1974

数据来源: Karger

摘要:

Galactose utilization was studied in 25 riboflavin-deficient patients, before and after administration of 10 mg of ribo flavin orally, for 10–15 days and 18 apparently healthy persons. Erythrocyte glutathione reductase activity was also studied in these subjects. In riboflavin-deficient patients, the tolerance to galactose loading was normal, whereas the activity of glutathione reductase in erythrocytes was lowered significantly compared to those observed in controls. Assay of galactokinase in erythrocytes and galactose-1-phosphate uridyl transferase in whole blood from riboflavin-deficient subjects revealed no significant change compared to normals. Following riboflavin administration, glutathione reductase levels were raised significantly in riboflavin-deficient subjects, but apparently the galactose tolerance and the activities of galactose-metabolising enzymes were not influenced. The possible role of riboflavin in the metabolism of galactose is discusse

ISSN:0250-6807    

DOI:10.1159/000175479

出版商:S. Karger AG    

年代:1974

数据来源: Karger

摘要:

During the manned lunar mission of Apollo 16, a study was undertaken to obtain more definitive information on human caloric requirements of prolonged exposure to weightless flight. Observations were made of immediate pre- and postflight body mass, total body water and exchangeable potassium. Continuous inflight recording of nutrient intake was achieved and partial metabolic excretory data were obtained. During weightlessness, the three crew members lost body water and adipose tissue. Caloric requirements calculated from these deficits proved to be different from those estimated prior to flight on the basis of body weight and age. The problem of predicting the metabolic cost of spaceflight is discussed.

ISSN:0250-6807    

DOI:10.1159/000175480

出版商:S. Karger AG    

年代:1974

数据来源: Karger

ISSN:0250-6807    

DOI:10.1159/000175481

出版商:S. Karger AG    

年代:1974

数据来源: Karger