Five ruminally cannulated steers (initial BW = 375 ± 34 kg; ADG = 1.16 ± 0.13 kg) were used in a 5 x 5 Latin square design experiment to determine the effects of increasing urea level on intake, nutrient digestion, nitrogen balance and ruminal kinetics. Isocaloric (NEm = 2.11 Mcal/kg; NEg = 1.35 Mcal/kg) and isonitrogenous (2.24% N) steam-flaked corn-based diets with urea concentrations of 0.0,...

The branchial mechanism of urea retention in elasmobranchs was investigated using an in vitro isolated-perfused head preparation, as well as in vivo samples, in the spiny dogfish shark. Both in vivo and in control saline perfusions containing 350 mmol L(-1) urea, calculated intracellular urea concentrations in gill epithelial cells were close to extracellular concentrations. Urea efflux to the ...

previous work by other investigators indicates a direct relation between the amount of protein in the diet and the level of urea in the blood . however, the present report shows that the type of protein , apart from its level in the ration , also has an effect on blood urea concentrations. when adult male or female rats of two strains were fed a ration in which the only source of protein was wh...

The urea tests of renal efficiency commonly mentioned in the literature include (a) simple estimation of blood urea concentration, (b) determination of urine urea concentration following ingestion of urea, and (c) observations on the relationship between blood and urine urea concentrations. From a comparative study of these three methods, the general conclusion reached in this hospital (1) was ...

Additive engineering in perovskites precursor solution is one of the most effective methods to fabricate high-quality perovskite films. Finding proper additives for morphology improvement and passivation defects critical highly efficient stable solar cells (PSCs). In this work, 1,3-disubstituted urea are employed study effect different substituents at −NH moiety on quality layer device performa...

In plants, urea derives either from root uptake or protein degradation. Although large quantities of urea are released during senescence, urea is mainly seen as a short-lived nitrogen (N) catabolite serving urease-mediated hydrolysis to ammonium. Here, we investigated the roles of DUR3 and of urea in N remobilization. During natural leaf senescence urea concentrations and DUR3 transcript levels...

HOUPT, T. RICHARD, AND KATHERINE A. HOUPT. Transfer of urea nitro,gen across the rumen wall. Am. J. Physiol. 2 1 /t(6) : 1296-1303. 1968.-Net movement of urea N across the wall of Pavlov-type rumen pouches was measured in three goats and one sheep as urea concentration difference between pouch and blood was varied. When urease activity of the rumen epitheliurn was depressed by vigorous rinsing ...

Saccharomyces cerevisiae can utilize arginine or urea as sole nitrogen source. Arginase degrades arginine to ornithine and urea; urea is catabolized to CO2 and NH3 by the urea degradation system which is composed of a urea carboxylase and an allophanate hydrolase. The arginine analogue, homoarginine, was shown to function as a nonmetabolizable inducer of arginase; it is also a competitive inhib...

ABSTRAKPanel kayu merupakan produk yang terbuat dari bahan direkatkan dengan menggunakan resin, perekat digunakan dalam produksi lapis resin urea-formaldehid (UF). Resin UF adalah thermosetting urea dan formaldehid akan mengeras jika dipanaskan dapat dicetak ulang. Pada penelitian ini, pembuatan baku Urea Formaldehyde Concentrate (UFC). Tujuan ini mempelajari pengaruh perubahan sifat kinerja UF...