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71.
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Four patterns of inositol fermentation by different isolates of Klebsiellae are described. Inositol fermentation by some isolates may be modified by medium incorporation of acetoin and diacetyl. An inositol--hydrogen sulphide--motility medium, modified by reducing the pH value, increasing the inositol concentration, and the incorporation of acetoin, is described and evaluated as a means of detecting acid production by isolates showing different inositol fermentation patterns. 相似文献
73.
RJ Harris 《Canadian Metallurgical Quarterly》1976,62(2):287-298
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Examined discrepancy scores (Verbal IQ minus Performance IQ) for the WISC-R, using the standardization sample--100 boys and 100 girls at each of 11 age levels between 61/2 and 161/2 yrs (2,200 Ss). The occurrence of significant discrepancy scores (Verbal > Performance and Performance > Verbal) was not significantly related to age, sex, or race, although significant relationships were obtained with both parental occupation and intelligence level. The mean absolute discrepancy score (regardless of sign) was about 10 IQ points for each age group, for boys and girls, for Blacks and Whites, and for the different occupational groups. Discrepancy score norms (cumulative distributions) are presented by intelligence level and are interpreted in terms of their clinical significance. Several of these findings closely parallel results of a study of the 1949 WISC by H. G. Seashore (see record 1952-06292-001). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
77.
The effectiveness in the year of application of three phosphorus fertilizers, superphosphate, Christmas Island C-grade ore, and 500°C calcined Christmas Island C-grade ore (Calciphos), was measured for 5 consecutive years in a field experiment on a lateritic soil. The residual value of the phosphorus fertilizers was also measured for 6 years. Dry matter production of subterranean clover-based pasture and bicarbonate extractable soil phosphorus were used as indicators of fertilizer effectiveness.Despite the use of very large amounts of C-grade ore and Calciphos, the plateau of the pasture yield versus fertilizer applied curve for these fertilizers did not reach the yield plateau achieved with superphosphate in either the short or long term.C-grade ore and Calciphos were 3% and 8% as effective as superphosphate for dry matter production in the year of application. Relative to superphosphate applied in the current year the effectiveness of superphosphate decreased by about 70% between the first and second year after application and decreased by a further 14% from year 3 to year 6. C-grade ore and Calciphos remained about 2% and 9% as effective as currently applied superphosphate each year.The residual value of superphosphate as measured by bicarbonate-extracted soil phosphorus decreased by about 60% from year 2 to year 7. The residual value of Calciphos was very low for year 2, doubled from year 2–4 and thereafter decreased gradually to its original value by year 7. The residual value of C-grade ore was extremely low throughout the experiment. Thus after year 2, compared to pasture yield, bicarbonate extracted soil phosphorus overestimated the residual value of superphosphate and calciphos.It follows that neither C-grade ore or Calciphos are suitable replacement fertilizers for superphosphate for use on pastures growing on lateritic soils in south-western Australia. 相似文献
78.
A Saunders S Hoibr?ten JJ Kraushaar BJ Kriss RJ Peterson RA Ristinen JT Brack G Hofman EF Gibson CL Morris 《Canadian Metallurgical Quarterly》1996,53(4):1745-1752
We calculated the electrostatic force between a planar interface, such as a planar-supported lipid bilayer membrane, and the tip of a stylus on which another lipid bilayer or some other biomacromolecular system might be deposited. We considered styli with rounded tips as well as conical tips. To take into account the effect of dynamical hydrogen-bonded structures in the aqueous phase, we used a theory of nonlocal electrostatics. We used the Derjaguin approximation and identified the systems for which its use is valid. We pointed out where our approach differs from previous calculations and to what extent the latter are inadequate. We found that 1) the nonlocal interactions have significant effects over distances of 10-15 A from the polar zone and that, at the surface of this zone, the effect on the calculated force can be some orders of magnitude; 2) the lipid dipoles and charges are located a distance L from the hydrophobic layer in the aqueous medium and this can have consequences that may not be appreciated if it is ignored; 3) dipoles, located in the aqueous region, can give rise to forces even though the polar layer is unchanged, and if this is ignored the interpretation of force data can be erroneous if an attempt is made to rationalize an observed force with a knowledge of an uncharged surface; 4) the shape of the stylus tip can be very important, and a failure to take this into account can result in incorrect conclusions, a point made by other workers; and 5) when L is nonzero, the presence of charges and dipoles can yield a force that can be nonmonotonic as a function of ionic concentration. 相似文献
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80.
Lack of sensitization to the effects of d-amphetamine and apomorphine on sensorimotor gating in rats
Haemolytic-uremic syndrome (HUS) is the leading cause of acute renal failure in the childhood. It is characterised by microangiopathic hemolytic anemia, thrombocytopenia, acute renal failure and injury of the renal microvascular endothelium. In HUS the condition of proteolytic kallikrein-kinin system is unknown. The renal KKS seems to participate in the regulation of blood pressure, control of sodium and water excretion, renal vascular resistance and renin release. In this study the role kallikrein in the developing HUS was studied. The general activity of kallikrein in plasma and urine was determined by trypsin-like peptidohydrolase activity (TP), which was measured using substrate Z-D-Ala-Leu-Arg-pNa. Chymotrypsin-like protease activity (ChP) was measured using substrate Glp-Ala-Ala-Leu-pNa. Clinical data were analysed on 60 pediatric patients with HUS, 29 girls and 31 boys, ranging in the age from 3 months to 11 years. TP and ChP levels were determined in different periods of HUS (anuria, diuresis beginning, polyuria, recovery) in serum and urine. In acute phase TP and ChP activities increased significantly. In diuresis recovery serum TP activity was higher, but urine TP level became normal. In dynamic serum and urine ChP levels had tendency to decrease. The present work showed that TP and ChP levels demonstrated activity of pathological renal process and condition of glomerules. 相似文献