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41.
A neonatal calf developed nervous symptoms followed by diarrhea. The principal pathological changes were fibrinopurulent meningitis with necrosis of the cerebral parenchyma, and attaching and effacing lesions in the intestine. Cerebral necrosis was frequently associated with vascular changes. Enterobacter cloacae was isolated from the brain and Escherichia coli (O128) from the intestinal content. These suggest that cerebral and intestinal lesions were caused by the isolated organisms, and that most necrosis of the cerebral parenchyma might be infarctive.  相似文献   
42.
Abstrac

The effects of 3 oxides (Fe, Al, and Mn oxides) and 3 clay minerals (kaolin, montmorillonite, and allophane) on the adsorption and subsequent kinetic properties of acid phosphatase were compared. The amount of enzyme adsorbed by the oxides and clay minerals followed the order: montmorillonite ? kaolin > Mn oxide > Fe oxide > Al oxide ? allophane. The adsorption isotherms of the enzyme on the oxides and clay minerals, except for montmorillonite and allophane, fitted the Langmuir equation. The activity of the enzyme immobilized by the inorganic components studied was in the order of allophane > kaolin > Fe oxide > montmorillonite > Al oxide ≒ Mn oxide. Compared to the free enzyme, the V max, Km, and V max / K m values of the immobilized enzyme decreased, increased, and decreased, respectively. Among the oxides or clay minerals, the higher the ability of the inorganic components to adsorb the enzyme, the lower the value of the V max / K m ratio of the immobilized enzyme. These findings suggest that the catalytic efficiency of the enzyme complexes formed is determined by the adsorbability of the inorganic components for the enzyme.  相似文献   
43.
The early stage of weathering / soil formation processes from new volcanic mudflow (new lahar materials) brought from Mt. Pinatubo was examined. For this purpose, comparative studies on the physical / chemical characteristics of the new lahar materials and soils formed by the deposition of old lahar materials were conducted. Original soils contained less coarse sand, more silt, and clay than the new lahar materials. Increase in the clay content of the original soils reflected the progression of weathering. The occurrence of a higher leaching process of Fe, Ca, and Mg and of a moderate accumulation of organic matter in the original soils was suggested, based on the differences in the soil elemental composition and chemical properties. Values of base saturation and phosphate absorption coefficient (PAC) of the new lahar materials were 388% and 44, while those of all the original soils ranged 15–160% and 55–894, respectively. With the progression of weathering, the PAC value tended to increase gradually while the base saturation value decreased abruptly under the environmental conditions prevailing in the Philippines.  相似文献   
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46.
Chloroform-extractable green fraction (CEGF) was detected in the supernatant obtained by alkali precipitation from the HCI-dimethylsulfoxide (DMSO) extract of Pg-rich soil. In the alkaline solution, the color of CEGF was green and CEGF showed strong Pg-like absorption bands. Ultraviolet and visible (UV-VIS) spectral analysis and gel chromatography on Sephadex G-50 were performed to compare several properties between CEGF and Pg. CEGF, which was purified by gel chromatography on Bio-Beads SX-1, displayed strong absorption bands at 609, 562, 445 and 280 inn in the alkaline solution. These absorption bands were almost similar to those of Pg. Furthermore, the UV-VIS spectrum of CEGF in the organic solvents showed a similar characteristic pattern of 4,9-dihydroxyperylene-3,10-quinone (DHPQ), which was considered to be a chromophore of Pg. Based on the results of gel chromatography on Sephadex G-50, CEGF mainly consisted of two fractions, corresponding to the G2 and G3 fractions of Pg. These results indicated that the method for extracting CEGF from Pg-rich soil in the present study was easy and selective and that CEGF was one of the components of, or a closely related substance to Pg. A colorimetric method for the estimation of the CEGF content in soils was developed. The calibration curve of CEGF was linear over a wide range of contents from 2.75 to 220 mg L−1. The CEGF content in twelve samples of various soils was examined. CEGF was detected in all the soil sampled (5 orders) including three samples (3 orders) where Pg was not detected, and the content ranged from 0.07 to 1.66 g kg−1 (dry soil). Therefore, the method for estimating the CEGF content in soils developed in the present study was found to be suitable for various soil orders and it was assumed that CEGF occurred in various soil orders.  相似文献   
47.
A novel stable precursor of ascorbic acid (vitamin C), 2-O-(beta-D-glucopyranosyl)ascorbic acid, was isolated from both the ripe fresh fruit and dried fruit of Lycium barbarum L., a plant of the Solanaceae family. The chemical structure was inferred by instrumental analyses and confirmed by chemical synthesis. The dried fruit of Lycium barbarum L. contained ca. 0.5% of it, which is comparable to the ascorbic acid content of fresh lemons. It increased the blood ascorbic acid by oral administration to rats, and it was also detected in blood from the portal vein.  相似文献   
48.
Earth's energy imbalance: confirmation and implications   总被引:2,自引:0,他引:2  
Our climate model, driven mainly by increasing human-made greenhouse gases and aerosols, among other forcings, calculates that Earth is now absorbing 0.85 +/- 0.15 watts per square meter more energy from the Sun than it is emitting to space. This imbalance is confirmed by precise measurements of increasing ocean heat content over the past 10 years. Implications include (i) the expectation of additional global warming of about 0.6 degrees C without further change of atmospheric composition; (ii) the confirmation of the climate system's lag in responding to forcings, implying the need for anticipatory actions to avoid any specified level of climate change; and (iii) the likelihood of acceleration of ice sheet disintegration and sea level rise.  相似文献   
49.
The morphology and chemical composition of fungal sclerotium-like grains collected from the buried humic horizon of volcanic ash soil in Mt. Myoko were examined using a scanning electron microscope (SEM), energy dispersion xray micro-analyzer (EDX), and electron probe micro-analyzer (EPMA). A high C content, low level of Si and high concentration of Al characterized the grains considered to correspond to the sclerotia of Cenoccocum graniforme. The 27Al MAS NMR spectrum of the sclerotia showed the existence of 6- and 4-coordinated Al. X-ray diffraction analyses supported the presence of amorphous Al (ex. Al-humus complex) in the sclerotia.  相似文献   
50.
Granulometric and clay mineralogical analyses were performed on soil types differing in their genesis which had been formed on the raised coral limestone terraces and plateaux under the perhumid subtropical maritime climate of the Ryukyu Islands. The amount of clay fraction in Rendzina-like soil on the lower terrace was relatively small (8-34%) and decreased with depth, while those in Terra fusca-like soils on the middle terraces and in Terra rossa-like soil on the plateau were very large (45–78%) suggesting the occurrence of clay migration.

Rendzina-like soil mainly contained illite and metahalloysite with a moderate amount of mixed layered mineral consisting of illite and vermiculite, and a small amount of vermiculite, Al-vermiculite, goethite, and quartz. Clay mineral composition of Terra fusca-like and Mottled Terra fusca-like soils was similar to that of Rendzina-like soil except that the content of illite was lower in these soils. Terra rossa-like soil, on the other hand, mainly contained Al-vermiculite, metahalloysite, and gibbsite, indicating a highly advanced stage of hydroxyaluminium interlayering. Differences in clay mineral composition from that of Rendzina, Terra fusca, and Terra rossa soils in the European countries were recognized, in that mont-morillonite was absent and hydroxyaluminium interlayering actively proceeded in the soils studied here. This finding is considered to reflect the rapid alteration and intense hydroxyaluminium interlayering of clay minerals under the perhumid subtropical conditions.  相似文献   
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