The relative impermeability of the surfaces of leaves to water and mineral ions in solution is a condition upon which the life of terrestrial higher plants depends. However, for the investigator this feature imposes difficulties on attempts to make quantitative studies of the process of ion absorption by leaf tissue. The importance of this absorption process in the physiology of leaf cells has ...

\Vitli the technical assistance of Arthur L. Foy T lIE STIMULUS to gastrointestinal absorption of iron remains unknown. Previous work seems to indicate that hepatic iron and total body iron stores are not as important as the rate of iron utilization in regulating iron absorption.’ Stimulation of erythropoiesis by blood letting increases iron utilization. However, following acute phlebotomy ther...

'Klemp P, Staberg B, Madsbad S, Kolcndorf K. Smoking reduces insulin absorption from subcutaneous tissue. Br MedJ' 1982;284:237. 2 Binder C. Absorption of injected insulin. Acta Pharmacol Toxicol (Copenh) 1969 ;27(suppl 2): 1-84. 3Berger M, Cuppers HJ, Hegner H, Jorgens V, Berchtold P. Absorption kinetics and biologic effects of subcutaneously injected insulin preparations. Diabetes Care 1982;5...

Absorption of L-methionine was measured in all parts of the human small intestine using transintestinal intubation and perfusion. In four normal subjects, adsorption was higher in the proximal than in the distal intestine. In two patients with nontropical sprue in relapse, there was a proximal zone of low absorption with higher absorption distally. In all parts of the small intestine, absorptio...

the reaction kinetics of the isomerization 3,4-dichlorobutene-1 to 1,4-dichlorobutene-2 was investigated by using gas-liquid chromatography method in the presence of fe2o3/mgo as solid catalyst in the temperature range 25-55°c. fe2o3/mgo has been prepared by the support saturation method, tested in the isomerization of 3, 4-dichlorobutene-1 into 1, 4-dichlorobutene-2. this catalyst shows a high...

the kinetics and mechanism of the reaction of 5-nitro-1h-benzo[d] imidazole to produce 6-nitro-1h-benzo[d] imidazole was studied by employing hybrid meta-density functional theory. mpwblk/6-31+g** level calculations were carried out to obtain energies and optimize the geometries of all stationary points along the pes, and determine the harmonic vibrational frequencies. two transition states (ts...

Quantum dots of CdS with hexagonal phase were prepared at relatively low temperature (60 oC) and short time by micro-emulsion (O/W) under ultrasound. This study was focused on the particle size distribution and the growth kinetics. The particle size distribution obtained from the optical absorption edge. It was relatively symmetrical with sonication time. In addition, an agreement was observed ...

Acetate absorption was studied in rat jejunum using steady state perfusion in vivo. Absorption conformed to apparent saturation kinetics and was similar in magnitude to glucose absorption. When compared with normal saline, acetate perfusion was associated with luminal alkalinisation. There was no difference in total CO2 secretion when similar rates of acetate and glucose absorption were compare...