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991.
E L Biberstein C E Franti S S Jang A Ruby 《Journal of the American Veterinary Medical Association》1974,164(12):1183-1186
992.
Zimmerman KL Wilcke JR Robertson JL Feldman BF Kaur T Rees LR Spackman KA 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2005,34(1):7-16
BACKGROUND: The Systematized Nomenclature of Medicine (SNOMED) is an established standard nomenclature for the expression of human and veterinary medical concepts. Nomenclature standards ease sharing of medical information, create common points of understanding, and improve data aggregation and analysis. OBJECTIVES: The objective of this study was to determine whether SNOMED adequately represented concepts relevant to veterinary clinical pathology. METHODS: Concepts were isolated from 3 different types of clinical pathology documents: 1) a textbook (Textbook), 2) the Results sections of industry pathology reports (Findings), and Discussion sections from industry pathology reports (Discussion). Concepts were matched (mapped) by 2 reviewers to semantically-equivalent SNOMED concepts. A quality score of 3 (good match), 2 (problem match), or 1 (no match) was recorded along with the SNOMED hierarchical location of each mapped concept. Results were analyzed using Cohen's Kappa statistic to assess reviewer agreement and chi-square tests to evaluate association between document type and quality score. RESULTS: The percentage of good matches was 48.3% for the Textbook, 45.4% for Findings, and 47.5% for Discussion documents, with no significant difference among documents. Of remaining concepts, 40% were partially expressed by SNOMED and 14% did not match. Mean reviewer agreement on quality score assignments was 76.8%. CONCLUSIONS: Although SNOMED representation of veterinary clinical pathology content was limited, missing and problem concepts were confined to a relatively small area of terminology. This limitation should be addressed in revisions of SNOMED to optimize SNOMED for veterinary clinical pathology applications. 相似文献
993.
994.
Two experiments were conducted to investigate effects of processing on apparent digestibility coefficients (ADCs) of legumes and oilseeds for juvenile silver perch, Bidyanus bidyanus (~49 g). The first experiment evaluated interactive effects of ingredients (lupins or field peas), processing (whole seed; hulls on or hulls off) and extrusion cooking (raw or extruded) on ADCs for juvenile silver perch (~4 g fish?1). The second experiment was a three‐fixed‐factor anova designed to evaluate interactive effects of ingredients (soybean meal or canola meal), extrusion cooking (raw or extruded) and inclusion content (30% or 50% of the diet) on ADCs for juvenile silver perch (~4 g fish?1). Lupin protein was more digestible than that of peas (ADC for crude protein 91% vs. 85% for peas) but the organic matter was less digestible (ADC for organic matter 50% vs. 67% for peas). Dehulling lupins significantly improved ADCs for all indices (dry matter, organic matter, energy and crude protein), but extrusion had no effect because lupins do not contain starch or heat‐labile anti‐nutrients. Conversely, for starch‐rich peas that contain heat‐labile trypsin inhibitors, both dehulling and extrusion significantly improved ADCs. Digestibility of soybean meal was much higher than that of canola meal. For soybean meal, neither processing, content nor their interaction affected digestibility but extrusion improved ADCs for dry matter, organic matter and energy but there was an interaction with content. Although higher overall, digestibility for these indices declined with increasing content for extruded product while there were only minor effects of inclusion for raw product. Benefits of extrusion were attributed to reductions in anti‐nutrients, including phytic acid. For canola, there were no interactions between extrusion and content for any ADC. Increasing content reduced ADCs for crude protein, dry matter and organic matter but did not effect energy. Surprisingly, extrusion of canola also reduced digestibility for all ADCs. Dehulling improved both lupins and peas. Crude protein for all ingredients was well digested with ingredients ranked: lupins>soybean meal>peas>canola meal. Energy digestibility was best for soybean meal and worst for lupins. Extrusion greatly improved digestibility of peas and to a lesser extent soybean meal, gave no benefits to lupins and was detrimental for canola. 相似文献
995.
Gas exchange, tissue water relations, and leaf/root dry weight ratios were compared among young, container-grown plants of five temperate-zone, deciduous tree species (Acer negundo L., Betula papyrifera Marsh, Malus baccata Borkh, Robinia pseudoacacia L., and Ulmus parvifolia Jacq.) under well-watered and water-stressed conditions. There was a small decrease (mean reduction of 0.22 MPa across species) in the water potential at which turgor was lost (Psi(tlp)) in response to water stress. The Psi(tlp) for water-stressed plants was -1.18, -1.34, -1.61, -1.70, and -2.12 MPa for B. papyrifera, A. negundo, U. parvifolia, R. pseudoacacia, and M. baccata, respectively. Variation in Psi(tlp) resulted primarily from differences in tissue osmotic potential and not tissue elasticity. Rates of net photosynthesis declined in response to water stress. However, despite differences in Psi(tlp), there were no differences in net photosynthesis among water-stressed plants under the conditions of water stress imposed. In A. negundo and M. baccata, water use efficiency (net photosynthesis/transpiration) increased significantly in response to water stress. Comparisons among water-stressed plants showed that water use efficiency for M. baccata was greater than for B. papyrifera or U. parvifolia. There were no significant differences in water use efficiency among B. papyrifera, U. parvifolia, A. negundo, and R. pseudoacacia. Under water-stressed conditions, leaf/root dry weight ratios (an index of transpiration to absorptive capacity) ranged from 0.77 in R. pseudoacacia to 1.05 in B. papyrifera. 相似文献
996.
997.
Female adult American cockroaches, Periplaneta americana L., showed definite age-dependent changes in levels of activity of the microsomal mixed-function oxidases. Cytochrome P-450 levels, EPN-detoxication, and p-nitroanisole O-demethylation activities were very low in young adult insects but increased steadily reaching a natural peak at about 100 days in fat body and at about 90 days in midgut and hindgut. The activities then declined rapidly reaching levels of young insects at about 130 to 140 days of age. NADPH-neotetrazolium-reductase activity was high in young insects, declined later in adult life, and returned to a peak at about 100 days.Injections of chlorcyclizine, a known microsomal enzyme inducer, significantly increased levels of cytochrome P-450, EPN-detoxication, p-nitroanisole O-demethylation, and NADPH-NT-reductase activities in young cockroaches. The drug injections were effective, however, only before the natural activity peak was reached. Beyond this point the injections had no inductive effect indicating that the microsomal oxidases in this insect are uninducible when normal enzyme levels are falling.NADPH-NT-reductase activity in male cockroaches, while being somewhat higher than in females, showed a similar age-dependent curve with the peak occurring at about 120 days.Age-dependent carbaryl resistance in male and female insects tended to follow levels of the microsomal oxidase activities. Fifty to 60-day-old insects, however, tended to be more resistant to the insecticide than microsomal enzyme levels would indicate.RNA levels of normal female insects showed age-dependent curves similar to those of the microsomal enzyme activities, being low in young adults and reaching a peak at about 100 days. Chlorcyclizine injections had little or no effect on total microsomal RNA levels. 相似文献
998.
999.
L. Leita M. De Nobili C. Mondini G. Muhlbachova L. Marchiol G. Bragato M. Contin 《Biology and Fertility of Soils》1999,28(4):371-376
We studied the long-term effects (12 years) of municipal refuse compost addition on the total organic carbon (TOC), the amount
and activity of the microbial biomass (soil microbial biomass C, BC and metabolic quotient qCO2) and heavy metal bioavaiability in soils as compared to manuring with mineral fertilizers (NPK) and farmyard manure (FYM).
In addition, we studied the relationships between among the available fraction [Diethylenetriaminopentacetic acid (DTPA) extractable]
of heavy metals and their total content, TOC and BC. After 12 years of repeated treatments, the TOC and BC of control and mineral fertilized plots did not differ. Soils treated with FYM and composts showed a significant increase
in TOC and BC in response to the increasing amounts of organic C added. Values of the BC/TOC ratio ranged from 1.4 to 2, without any significative differences among soil treatments. The qCO2 increased in the organic-amended soil and may have indicated microbial stress. The total amounts of metals in treated soils
were lower than the levels permitted by the European Union in agricultural soils. DTPA-extractable metals increased in amended
soils in response to organic C. A multiple regression analysis with stepwise selection of variables was carried out in order
to discriminate between the influence exerted on DTPA-extractable metals by their total content, TOC and BC. Results showed that each metal behaved quite differently, suggesting that different mechanisms might be involved in metal
bioavailability
Received: 31 October 1997 相似文献
1000.
Effects of different arginine/lysine level on growth performance,body composition and digestive enzyme activity of Macrobrachium rosenbergii 下载免费PDF全文
X. J. Dong J. Wu Y. Shen J. Y. Chen S. Y. Miao X. J. Zhang L. S. Sun 《Aquaculture Nutrition》2018,24(3):1101-1111
Given the universal presence of antagonism between arginine and lysine, determining the optimal dietary arginine/lysine level is of great importance. In this study, eight diets were formulated to contain different arginine/lysine level, followed by a 9‐week feeding trial with shrimps of 2.10 ± 0.01 cm in length and 0.38 ± 0.02 g in weight to determine the effect of dietary arginine/lysine level on growth performance, body composition and enzyme activity. The results showed that the Diet 6 (arginine/lysine level of 29.4/21.0 g/kg) group had significantly higher weight gain rate, and specific growth rate than the control group and most of the other groups (p < .05) did. Similarly, the retention efficiency of arginine and lysine in the Diet 6 group was significantly higher than the control group and most of the other groups (p < .05). Moreover, most digestive enzymes had higher activity levels in the Diet 6 group, and evident antagonism between dietary arginine and lysine was detected. In summary, dietary arginine/lysine level of 29.4/21.0 g/kg produced the best growth performance, suggesting that a better growth performance in Macrobrachium rosenbergii culture can be obtained by adjusting the dietary arginine/lysine level. 相似文献