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391.
392.
Rona Miethling-Graff Susanne Dockhorn Christoph C. Tebbe 《European Journal of Soil Biology》2010,46(1):41-48
A three-year experimental field study with a genetically engineered Bt maize (event MON88017) and three conventionally bred cultivars was conducted to quantify the recombinant Cry3Bb1 protein released into soil and detect effects on the diversity of soil bacteria. Protein extraction and an enzyme-linked immunosorbent assay (ELISA) allowed a threshold detection of 0.01 ng Cry3Bb1 g?1 soil. The maximum amount found in field plots with Bt maize was 1.0 ng Cry3Bb1 g?1 rhizosphere soil. Average concentrations during the growing seasons varied between years from 0.07 to 0.29 ng g?1. No accumulation of Cry3Bb1 in soil occurred over the three growing seasons. Four weeks after harvest, the major Cry3Bb1 reservoirs on the field were the remaining root stubbles, but their Cry3Bb1 concentration declined by 98.30–99.99% in the following seven months. During the three consecutive years of study there were never significant differences between the rhizosphere bacterial community structure of the Bt maize and the other cultivars, as detected by cultivation independent profiling of PCR-amplified 16S rRNA genes. The low concentrations of soil extractable Cry3Bb1, its degradation in decaying roots, and the lack of effects on rhizosphere bacteria give no indications of adverse effects of MON88017 cultivation on soil ecology. 相似文献
393.
Nicolas P Mäder U Dervyn E Rochat T Leduc A Pigeonneau N Bidnenko E Marchadier E Hoebeke M Aymerich S Becher D Bisicchia P Botella E Delumeau O Doherty G Denham EL Fogg MJ Fromion V Goelzer A Hansen A Härtig E Harwood CR Homuth G Jarmer H Jules M Klipp E Le Chat L Lecointe F Lewis P Liebermeister W March A Mars RA Nannapaneni P Noone D Pohl S Rinn B Rügheimer F Sappa PK Samson F Schaffer M Schwikowski B Steil L Stülke J Wiegert T Devine KM Wilkinson AJ van Dijl JM Hecker M Völker U Bessières P 《Science (New York, N.Y.)》2012,335(6072):1103-1106
394.
Di Concetto S Mandsager RE Riebold TW Stieger-Vanegas SM Killos M 《Veterinary anaesthesia and analgesia》2012,39(1):99-105
Objective To investigate whether rostral extension of the hind limbs increases the cranio‐caudal dorsal interlaminar distance between the seventh lumbar vertebra and the sacral bone (LS distance) in sternally recumbent anesthetized dogs. Study design Prospective clinical study. Animals Eighteen dogs (eight neutered males, three intact males, six spayed females, one intact female) of various breeds, weighing 4–34 kg and ranging in age from 1 to 13 years. Methods Each dog was grouped by size: small (≤10 kg), medium (15–20 kg) or large (≥25 kg). Each dog was anesthetized and positioned in sternal recumbency. Computed tomography (CT) of the lumbosacral area was performed with the hind limbs resting on the stifle and the feet extended posteriorly, and then with the hind limbs extended rostrally. LS distance, craniocaudal dorsal interlaminar distance between sixth and seventh lumbar vertebra (L6–L7 distance), length of L7 vertebral body and lumbosacral angle (LS angle) were measured on a reconstructed mid‐sagittal CT image from the two hind limb positions. The measurements from the two hind limb positions for the whole dog population and by size were compared using Student’s T tests. Diagnostic interpretation of the CT images was performed. Results The length of L7 was taken as the reference value as it was not affected by hind limb position. LS distance, L6–L7 distance and LS angle were significantly higher when the hind limbs were extended rostrally in all three size groups. The CT images of ten dogs showed clinically undetected osteoarthrosis of the ileo‐ and lumbosacral area. Conclusions and clinical relevance Rostral extension of the hind limbs significantly increases LS and L6–L7 distance and LS angle even in dogs with clinically undetected osteoarthrosis of the ileo‐ and lumbosacral area, and may enhance the ease of lumbosacral epidural injection in sternally recumbent anesthetized dogs. 相似文献
395.
lvaro Gmez Gutirrez Susanne Schnabel Francisco Lavado Contador 《Land Degradation \u0026amp; Development》2009,20(5):535-550
Gully erosion plays an important role in degradation processes of Mediterranean environments. In this paper aerial orthophotographs were used for (i) analysing the evolution of a valley bottom gully and its relation with land use and vegetation cover, (ii) exploring the role of land use and vegetation cover on the coefficients of the equation S = aA −b (where S is slope at the headcut and A is drainage area), which is based on the topographical threshold concept and is commonly used to predict gully initiation. The study was carried out in a small catchment (99·5 ha) located in the southwest of the Iberian Peninsula. Gullies and headcuts were mapped together with land use and vegetation cover using aerial photographs for the years 1945, 1956, 1989, 1998, 2002 and 2006, which had to be digitized and orthorectified in advance. The results showed an increase of the area affected by gullying from 695 m2 in 1945–1009 m2 in 2006, reaching a maximum of 1560 m2 in 1956. Gullying was closely related with land use, especially with the amount of cultivated areas within the catchment and also with grazing intensity. No clear relationship was found between the evolution of the gullied area and rainfall amounts. Finally, the values of the exponent b obtained for different headcuts and different dates (close to 0·4) were similar to those proposed by other authors for gully erosion caused by Hortonian overland flow in semiarid environments. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
396.
Phytochemical profile of main antioxidants in different fractions of purple and blue wheat, and black barley 总被引:1,自引:0,他引:1
Siebenhandl S Grausgruber H Pellegrini N Del Rio D Fogliano V Pernice R Berghofer E 《Journal of agricultural and food chemistry》2007,55(21):8541-8547
Two pigmented wheat genotypes (blue and purple) and two black barley genotypes were fractionated in bran and flour fractions, examined, and compared for their free radical scavenging properties against 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt radical cation (Trolox equivalent antioxidant capacity, TEAC), ferric reducing antioxidant power (FRAP), total phenolic content (TPC), phenolic acid composition, carotenoid composition, and total anthocyanin content. The results showed that fractionation has a significant influence on the antioxidant properties, TPC, anthocyanin and carotenoid contents, and phenolic acid composition. Bran fractions had the greatest antioxidant activities (1.9-2.3 mmol TEAC/100 g) in all four grain genotypes and were 3-5-fold higher than the respective flour fractions (0.4-0.7 mmol TEAC/100 g). Ferulic acid was the predominant phenolic acid in wheat genotypes (bran fractions) while p-coumaric acid was the predominant phenolic acid in the bran fractions of barley genotypes. High-performance liquid chromatography analysis detected the presence of lutein and zeaxanthin in all fractions with different distribution patterns within the genotypes. The highest contents of anthocyanins were found in the middlings of black barley genotypes or in the shorts of blue and purple wheat. These data suggest the possibility to improve the antioxidant release from cereal-based food through selection of postharvest treatments. 相似文献
397.
Theory predicts that linkage between genetic loci reduces the efficiency of purifying selection. Because of the permanent linkage of all heritable genetic material, asexual lineages may be exceptionally prone to deleterious-mutation accumulation in both nuclear and organelle genes. Here, we show that the ratio of the rate of amino acid to silent substitution (Ka/Ks) in mitochondrial protein-coding genes is higher in obligately asexual lineages than in sexual lineages of the microcrustacean Daphnia pulex. Using a phylogeny-based approach to quantify the frequency of mutational-effect classes, we estimate that mitochondrial protein-coding genes in asexual lineages accumulate deleterious amino acid substitutions at four times the rate in sexual lineages. These results support the hypothesis that sexual reproduction plays a prominent role in reducing the mutational burden in populations. 相似文献
398.
Dykgraaf S Pusterla N Van Hoogmoed LM 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2006,20(4):998-1002
BACKGROUND: Rattlesnake envenomation of New World camelids is a seasonal problem with often dramatic clinical signs. HYPOTHESIS: The purpose of this study was to identify the clinical signs, laboratory results, treatment methods, and outcome for rattlesnake envenomation in New World camelids. ANIMALS: Medical records from 1988 to 2004 were searched for New World camelids presented for rattlesnake bite or clinical signs suspected to be related to recent envenomation. Twelve records were identified. METHODS: From these records a retrospective study was performed. RESULTS: Nine camelids presented for acute disease (2/9 arrived dead), whereas 3 presented for subacute onset of disease. Swelling of the lips, head and neck, tachypnea, dyspnea, tachycardia, and lethargy were the most common presenting signs. Snake bites were most commonly located to the muzzle (10/12). Common complete blood count (CBC) and serum biochemical abnormalities were neutrophilia, lymphopenia, increased muscle enzyme activity, hypoalbuminemia, hyperglycemia, hypokalemia, and thrombocytopenia. Treatment included combinations of intravenous fluid therapy, antimicrobials, anti-inflammatory drugs, tetanus prophylaxis, tracheostomy, supplemental oxygen, antivenom, total parenteral nutrition, and nursing care. Five of the 10 animals with acute onset of clinical signs survived, and all animals with subacute presentation died. The mortality rate for New World camelids with severe local tissue reaction and systemic signs of envenomation was 58%. CLINICAL IMPORTANCE: New World camelids that sustain rattlesnake envenomation and severe facial swelling precluding prehension and mastication have a guarded prognosis for survival. Aggressive treatment is recommended to optimize the chances of survival. Animals with less severe local tissue reaction and absence of systemic signs have a better prognosis. 相似文献
399.
A method based on a derivatization with dansyl chloride and LC-MS-MS determination was developed for the quantitation of 2-methylbutyl-, 3-methylbutyl-, 2-phenylethyl-, 3-(methylthio)propyl-, and 2-methylpropylamine. Its application on unfermented, fermented, and roasted cocoas from Ghana and Sulawesi revealed an increase of all amines, except the 3-(methylthio)propylamine, during cocoa fermentation, suggesting an enzymic formation from the parent amino acids isoleucine, leucine, phenylalanine, and valine. However, a much more pronounced formation of most of the amines was measured after roasting of the cocoa, leading to concentrations in the milligrams per kilogram range. This result suggested a new "thermogenic" formation pathway of "biogenic amines". A comparison of the amounts of the amines and the aldehydes in roasted cocoa revealed similar concentrations, for example, for 2- and 3-methylbutanal and the respective amines, whereas the amounts of 2-phenylethylamine were much higher as compared to the amounts of phenylacetaldehyde. Strecker-type model systems, in which each parent amino acid was reacted with 2-oxopropanal, revealed the formation of both the amine and the aldehyde; however, in contrast to cocoa, the concentrations of the aldehydes were always much higher as compared to the amines. The results showed for the first time the thermally induced generation of "biogenic amines" from amino acids. Possible reasons for the different ratios of amines versus aldehydes formed during the roasting of cocoa or the model systems, respectively, are discussed. 相似文献
400.
Siener R Hönow R Voss S Seidler A Hesse A 《Journal of agricultural and food chemistry》2006,54(8):3008-3011
Detailed knowledge of food oxalate content is of essential importance for dietary treatment of recurrent calcium oxalate urolithiasis. Dietary oxalate can contribute considerably to the amount of urinary oxalate excretion. Because cereal foods play an important role in daily nutrition, the soluble and total oxalate contents of various types of cereal grains, milling products, bread, pastries, and pasta were analyzed using an HPLC-enzyme-reactor method. A high total oxalate content (>50 mg/100 g) was found in whole grain wheat species Triticum durum (76.6 mg/100 g), Triticum sativum (71.2 mg/100 g), and Triticum aestivum (53.3 mg/100 g). Total oxalate content was comparably high in whole grain products of T. aestivum, that is, wheat flakes and flour, as well as in whole grain products of T. durum, that is, couscous, bulgur, and pasta. The highest oxalate content was demonstrated for wheat bran (457.4 mg/100 g). The higher oxalate content in whole grain than in refined grain cereals suggests that oxalic acid is primarily located in the outer layers of cereal grains. Cereals and cereal products contribute to the daily oxalate intake to a considerable extent. Vegetarian diets may contain high amounts of oxalate when whole grain wheat and wheat products are ingested. Recommendations for prevention of recurrence of calcium oxalate stone disease have to take into account the oxalate content of these foodstuffs. 相似文献