soil enzyme activities can be used as indicators of soil quality for assessing the sustainability of agricultural ecosystems. the objective of this study was to determine the effects of barley residue input rate, burning, urea fertilizer and tillage management on activities of alkaline phosphatase and urease under field conditions, after a period of 90 days. the experiment was carried out based...

OBJECTIVES a) To determine the rate of H. pylori reinfection after successful eradication in a 4-year follow-up study; and b) To evaluate the contribution of different factors in the infection relapse. PATIENTS AND METHODS A total of 208 patients (age range 18-81 years; average 50 years; 87 women) who had been successfully treated for H. pylori infection were included. Annually, urea breath t...

Shangraw, Robert E., and Farook Jahoor. Effect of liver disease and transplantation on urea synthesis in humans: relationship to acid-base status. Am. J. Physiol. 276 (Gastrointest. Liver Physiol. 39): G1145–G1152, 1999.—It has been suggested that hepatic urea synthesis, which consumes HCO3 , plays an important role in acid-base homeostasis. This study measured urea synthesis rate (Ra urea) dir...

The objective of the present study was to delineate how interactions between feeding sunflower oil (SFO) to partially defaunate the rumen and altering dietary ruminally fermentable carbohydrate may alter urea-N kinetics and N metabolism in lambs. In a 4 × 4 Latin square with a 2 × 2 factorial arrangement of treatments, four Suffolk ram lambs (61·5 (se 4·0) kg) were used. Treatments were 0 ( - S...

Five Angus x Hereford steers with ruminal and duodenal fistulas were used in a 5 x 5 Latin square to determine effects of increasing the proportion of urea in supplemental degradable intake protein (DIP) on intake, fermentation, and digestion. Steers had ad libitum access to low-quality, tallgrass-prairie forage (2.4% CP, 76% NDF). Supplemental DIP (380 g/d) was from sodium caseinate and(or) ur...

1. Prochymosin in solution in the presence of 8 M-urea is fully unfolded, as indicated by its fluorescence spectrum, fluorescence quenching behaviour and far-u.v.c.d. spectrum. 2. Equilibrium studies on the unfolding of prochymosin and pepsinogen by urea were carried out at pH 7.5 and pH 9.0. The results indicate that the stabilization energies of the two proteins are identical at pH 7.5, but t...

Increased environmental pH decreases ammonia transport through the gills, impairing nitrogenous waste. The consequent toxicity is usually drastic to most fishes. A few species are able to synthesize urea as a way to detoxify plasma ammonia. We studied three teleosts of the family Erythrinidae living in distinct environments, and assumed the biochemical behaviors would be different in spite of t...

Intensively managed forest plantations often require fertilization to maintain site fertility and improve growth yield over successive rotations. We applied urea-based “enhanced-efficiency fertilizers” (EEF) containing 0.5 atom% 15N at a rate of 224 kg N ha−1 soils under mid-rotation black walnut (Juglans nigra L.) track the fate within aboveground ecosystem components during 12-month period af...