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161.
Preincubation of resting cells of Saccharomyces cerevisiae double mutant can1 gap1 (with a single transport system for L-lysine) with metabolic substrates stimulated subsequent uptake of lysine. While in the wild type the stimulation is connected primarily with carrier protein synthesis (delayed, cycloheximide-inhibitable effect) in the mutant an immediate tapping of an energy source (antimycin-inhibited) is practically solely involved.  相似文献   
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Frequency of infection by Cryptosporidium sp. in 1,039 faecal smears stained by Ziehl-Neelsen, obtained from undernourished patients of a Nutritional Recovery Center and an ambulatory undernourished center from the Fifth Region, Chile, were studied. All underwent a coproparasitological examination by the modified Telemann method. Thirty eight (3.7%) patients infected by the parasite were detected, with an overall frequency of 8.5% among patients of the Nutritional Recovery Center and 1.9% among the ambulatory patients; this difference was statistically significant. The highest percentage of positive results were detected among the younger milk feeding infants. Also the percentage of difference among these and the older milk feeding infants (3.7%) was statistically significant. Association of Cryptosporidium sp. and Giardia lamblia was observed in 6 ambulatory patients (2.3%).  相似文献   
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In order to recognize the realizability of inputs with different physical natures through a component, Yoneda's Lemma is applied. The major utility of this Lemma is when the components produce only energy. From this, it is assumed that a new material input must exist which was not recognized in the original developments in biological systems representation. Moreover, simple transfers of energy, between objects, components, and among both objects and components are developed under the generic name; energetical evolution. Thus, energetical evolution appears as anew element in the abstract representation of biological systems. These new concepts are incorporated into a new abstract diagram and a newM β category. This paper was made possible by a Fellowship from the Consejo Nacional de Investigaciones Científicas y Técnicas of the República Argentina.  相似文献   
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The pmr spectra of fully acetylated 2S: 3R-2 amino-trans-4 octadecene-1, 3 diol (sphingosine) (lb), 2S : 3R-2 aminooctadecane-1, 3 diol (dihydrosphingosine) (2b), 1-O-β-D-galactopyranosyl-2S : 3R-2 tetracosanoylamido-trans-4 octadecene-1, 3 diol (cerasine) (3b), and 1-O-β-D-galactopyranosyl-2S : 3R-2 (2′ hydroxy) tetracosanoylamido-trans-4 octadecene-1, 3 diol (phrenosine) (4b), were determined in chloroform-d, acetone-d6, and benzene-d6 at 220 MHz. The relative chemical shifts of the various protons in the three solvents were different enough as to permit configurational and conformational information to be derived by partial first order analysis.  相似文献   
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