Animal utility

Quantitation of the oral bronehodilator 2,5-diethyl-7-(tetrahydro-l,4-thiazin-4-yl)-l,2,4-triazolo[l,5-c]pyrimidine (R-836) (195) in plasma and urine of humans and experimental animals utilized reversed-phase HPLC and UV deteetion (88MI1). 

Another route to the formation of piperidine heterocycles is cyclization via reductive animation utilizing various hydride sources. The scheme below depicts a bis reductive animation, using sodium triacetoxyborohydride as the hydride source, to generate exo-178 and endo-179 azabicyclo[3.2.1]octane amino acids in moderate yields <06JOC8467>. 

Positive results in the mammalian in vivo bone marrow chromosome aberration test indicate that a substance induces stmctural chromosome aberrations in the bone marrow of the species tested. An increase in polyploidy (a multiple of the haploid chromosome number (n) other than the diploid number, i.e., 3n, 4n and so on) may indicate that a substance has the potential to induce numerical aberrations (change in the number of chromosomes from the normal number characteristic of the animals utilized). 

Chromosomal aberrations include both numerical and structural aberrations. Numerical aberrations are changes in the number of chromosomes of the normal number characteristic of the animals utilized (aneugenicity). Structural aberrations are classified into two types, chromosome or chromatid aberrations (clastogenicity). Chromosomal mutations and related events are the cause of many human genetic diseases and there is evidence that chromosomal mutations and related events are involved in cancer development. 

A major consideration is whether humans can utilize the D-enanticmers of essential amino acids. Berg (67) has reviewed human and animal utilization of free D-amino acids. L-Amino acids are invariably taken up faster than the D-enanticmers in the intestine (68, 69) and kidney (70). 

Animations utilizing the Bohr model may be found at the following two URLs http //artsci-ccwin.concordia.ca/facstaff/a-c/bird/c241/D1.html and http //www.mhhe.com/phvssci/chemistrv/essentialchemistrv/flash/linesp16.swf... 

We must consider Marco Polo (Sept. 15, 1254-Jan. 8, 1324 ce), a Venetian merchant, the first botanical exploret of the modern era. For 17 years, Kublai Khan employed him. Although Polo was a keen observer of Chinese traditions and described many plants and animals utilized in China, he made obvious omissions such as tea, fishing with cormorants, footbinding, chop sticks, and soy. Polo probably ate soy products but was unable to associate the food products made from soy with the crop growing in the fields (Penzer, 1929 Olschki, I960 Rugoff, 1961). 

Experiments using a habituation technique have shown that the tamarins are able to discriminate between the scent marks of two unknown individuals of the same sex (Epple et al., 1979). An additional experiment strongly suggested that the animals utilize scent to identify known individuals. 

With respect to racemization, a major consideration is whether humans can utilize the D-enantiomers of essential amino acids (Stegink, 1977 Masters and Friedman, 1980). Berg (1959) reviewed human and animal utilization of free D-amino acids. Uptake of L-amino acids is invariably faster than that of the D-enantiomers in the intestine (Gibson and Wiseman, 1951 Finch and Hird, 1960) and kidney (Rosenhagen and Segal, 1974). Once absorbed, D-amino acids can be utilized by two pathways (1) racemases (or epimerases) may convert D-isomers to DL-forms or (2) D-amino acid oxidases may catalyze oxidative deamination to a-keto acids, which can be specifically reaminated to the natural L-forms (Meister, 1965). Only the latter activity has been demonstrated in mammals. However, when mixtures of D-amino acids are fed to rats, the oxidase system can be overloaded so that the D-enantiomers of essential amino acids cannot be transaminated in sufficient quantity to support growth (Wretlind, 1952). 

Livestock supplementation. Cobalt-deficient fodder such as grasses (contain less than 0.08 ppm) may cause serious losses of livestock and lead to vitamin Bn deficiency in humans consuming animal products. Farm animals utilize relatively small amounts of vitamin Bn, ranging from 0.05 to 0.5 mg per kg of their weight, but its content in animal feed is also very low. An effective utilization of the vitamin is due to the high affinity binding proteins. Low yields of cobalamins in the rumen of animals result from a relatively short period of bacterial transit and anaerobic conditions, unfavorable for the synthesis of the cobalamin precursor DMB. When DMB... 

Animals utilize roughage materials by bacterial action. The bacterial digestion allows the cellulose and pentosans in feed materials to be converted to usable organic acids. The chief acid metabolites include acetic, propionic, and butyric. The volatile fatty acids are absorbed through the ruminal... 

The second section in this chapter briefly reviews biomimetic robots using IPMC actuators. Fishlike robots are reviewed firstly. In the experiment of a snake robot, the wave motion grows from the head to the tail even without feedback control. This interesting phenomenon may support a hypothesis that living animals utilize the... 

Food producing animals utilize a sniffing behavior often associated with the apprehension, selection and prehension of feeds. The Inportance of odor in food selection by sheep was Investigated by offering control and bulbectomized sheep food from control containers versus containers that had been adulterated with acetic acid, camphor or iodobenzene (Table IV). Bulbectomized sheep selected approximately equal quantities of food from each container whereas control sheep only consumed about 25% of their 60-minute Intake from adulterated containers (31). 

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