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51.
52.
Roleff S Arndt G Bottema B Junker L Grabner A Kohn B 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2007,36(2):155-166
BACKGROUND: The CA530-VET is a completely automated impedance cell hematology analyzer, which yields a 16-parameter blood count including a 3-part leukocyte differential. OBJECTIVES: The aim of this study was to examine the operational potential of the CA530-VET and its value for use in veterinary practice. METHODS: The analyzer was tested for blood carry-over, precision, and accuracy. Comparison methods included the CELL-DYN 3500, microhematocrit centrifugation, manual platelet (PLT) counting for feline and equine species, and a 100-cell manual WBC differential. Blood samples for comparison of the methods were obtained from 242 dogs, 166 cats, and 144 horses. RESULTS: The carry-over ratio (K) was 0.28% for RBC, 0.59% for PLT, 0.32% for WBC, and 0.18% for hemoglobin (HGB) concentration. Coefficients of variation (CVs) for within-batch precision and duplicate measurement of blood samples were clearly within the required limits, except for duplicate platelet counts in cats (8.7%) and horses (9.5%). The WBC count was in excellent agreement for dogs and horses and RBC count was in excellent agreement for horses. The accuracy of feline WBC counts was not acceptable, with the exception of values at the high end of the range. RBC counts in dogs and cats, and HGB concentration and MCV in all 3 species were sufficiently accurate. The CA530-VET HCT results were in excellent agreement with microhematocrit results in horses but exceeded the maximum allowed inaccuracy for cats and dogs. In all species, PLT counts established mechanically and manually were not in adequate agreement. Large differences were found between the CA530-VET and the manual differential percentage for lymphocytes and "mid-sized cells" (monocytes and basophilic granulocytes). CONCLUSIONS: The CA530-VET can be considered useful for routine canine, feline, and equine blood cell analyses. It should not be considered accurate, however, for PLT counts, feline total WBC counts in the subnormal and normal range, and leukocyte differentials, except for granulocytes. 相似文献
53.
Noel M. Lacerna II Cydee Marie V. Ramones Jose Miguel D. Robes Myra Ruth D. Picart Jortan O. Tun Bailey W. Miller Margo G. Haygood Eric W. Schmidt Lilibeth A. Salvador-Reyes Gisela P. Concepcion 《Marine drugs》2020,18(12)
The bioactivity-guided purification of the culture broth of the shipworm endosymbiont Teredinibacter turnerae strain 991H.S.0a.06 yielded a new fatty acid, turneroic acid (1), and two previously described oxylipins (2–3). Turneroic acid (1) is an 18-carbon fatty acid decorated by a hydroxy group and an epoxide ring. Compounds 1–3 inhibited bacterial biofilm formation in Staphylococcus epidermidis, while only 3 showed antimicrobial activity against planktonic S. epidermidis. Comparison of the bioactivity of 1–3 with structurally related compounds indicated the importance of the epoxide moiety for selective and potent biofilm inhibition. 相似文献
54.
Selection for improved nitrogen-utilization in Lolium
In a 3-year study the responses of 14 Lolium perenne-varieties and 14 of Lolium multiflorum to different nitrogen fertilization (75, 150, 300 kg N/ha) were investigated. The varieties were classificated into four types of nitrogen utilization. "Low input varieties" can be found in type III. The varieties of this type produced always the highest yield at all levels of nitrogen fertilization. The yield of type I was always smaller than the average of all varieties. The varieties of type II gave significant better responses than the trial average up to 150 kg N/ha. Under low and high N-fertilization the type III can be separate of type I and II because it is always the outstanding variety. The dry matter production of the roots did not show varieties differences under the increasing N-fertilization. The soil nitrate contents were with 20 kg nitrate nitrogen per ha very small. 相似文献
In a 3-year study the responses of 14 Lolium perenne-varieties and 14 of Lolium multiflorum to different nitrogen fertilization (75, 150, 300 kg N/ha) were investigated. The varieties were classificated into four types of nitrogen utilization. "Low input varieties" can be found in type III. The varieties of this type produced always the highest yield at all levels of nitrogen fertilization. The yield of type I was always smaller than the average of all varieties. The varieties of type II gave significant better responses than the trial average up to 150 kg N/ha. Under low and high N-fertilization the type III can be separate of type I and II because it is always the outstanding variety. The dry matter production of the roots did not show varieties differences under the increasing N-fertilization. The soil nitrate contents were with 20 kg nitrate nitrogen per ha very small. 相似文献
55.
Promotion of plant growth and nutrient uptake of cruciferous oil- and intercrops by inoculated rhizosphere microorganisms The vegetative growth of rape, oil radish and mustard was repeatedly stimulated by isolates of Pseudomonas fluorescens (PsIA12), P. putida (A1 A2), Stenotrophomonas maltophilia (PsIB2, Psl2), Agrobacterium rhizogenes (A1A4) and Rhizobium trifolii (R39) by improved root development and nutrient uptake (N. P. K. Mg) in pot and field experiments on loamy sand and sandy loam at different yield levels. The seed yield of rape could be increased only by 2 isolates (PsIA12, PsIB2). The growth stimulating bacteria produced phytohormones (auxins and partly cytokinins). No direct relations between plant growth stimulation and the potential microbial metabolic activities nitrogenase, nitrate reductase, P-mobilization, pectinase, cellulase could be found. Effective bacteria are in close association with the plants and can survive in the rhizosphere. 相似文献
56.
Gisela Höflich Undine Behrendt Wolfgang Seyfarth 《Archives of Agronomy and Soil Science》2013,59(5-6):339-358
Phyllosphären‐ und Rhizosphärenbakterien (Pseudomonas spp., Pantoea spp., Agrobacterium spp., Rhizobium spp. bzw. Stenotrophomonas spp.) stimulierten unabhängig von der Herkunft (Getreide, Mais, Gräser, Raps, Rotklee, Kiefern) das Wachstum von W.‐Weizen, Mais und Erbsen in gemäßigten Klimaten. Sie überlebten nach Sproß‐ und Wurzelinokulation bevorzugt im Rhizosphärenraum. Auch Phyllosphärenbakterien wanderten nach Sproßinokulation in die Rhizosphäre ab. In gemäßigten Klimaten sind Wachstumsstimulierungen nicht an eine Nitrogenaseaktivität der Bakterien gebunden. Phytoeffektive Bakterien bildeten meist Phytohormone, Auxine und z.T. Cytokinine, die in den bevorzugt besiedelten Seitenwurzelzonen und Wurzelspitzen das Wurzelwachstum und die Nährstoffaufnahme aus dem Boden förderten. Das wirkte sich auch positiv auf den Chlorophyllgehalt in Maisblättern aus. Mögliche Unterschiede zur Bedeutung des Besiedlungsverhaltens und mikrobieller Stoffwechselleistungen in tropischen Klimaten werden diskutiert. 相似文献
57.
Polar ice provides an archive for the influx of cosmic dust. Here, we present a high-resolution, glacial-to-interglacial record of cosmic dust using helium isotope analysis of the European Project for Ice Coring in Antarctica (EPICA) ice core drilled in Dronning Maud Land. We obtained a relatively constant 3He flux over the past 30,000 years. This finding excludes 3He as a pacemaker of late Pleistocene glacial cycles. Rather, it supports 3He as a constant flux parameter in paleoclimatic studies. A last glacial-to-Holocene shift of the 4He/non-sea salt Ca2+ ratio appears to indicate a glacial-to-interglacial change in the terrestrial dust source. 相似文献
58.
59.
Taupp M Harmsen D Heckel F Schreier P 《Journal of agricultural and food chemistry》2005,53(24):9586-9589
Bacillus megaterium, isolated in a screening process from topsoil, was used for N-demethylation of natural N-methyl methyl anthranilate to produce natural methyl anthranilate. Maximal productivity of 70 mg/L/day was achieved under laboratory-scale conditions without further optimization. No byproducts were observed. Thus, production of "natural" methyl anthranilate using B. megaterium is a significant improvement over comparable already existing procedures. 相似文献
60.
Dongowski G Jacobasch G Schmiedl D 《Journal of agricultural and food chemistry》2005,53(23):9257-9267
Microbial metabolism is essential in maintaining a healthy mucosa in the large bowel, preferentially through butyrate specific mechanisms. This system depends on starch supply. Two structurally different resistant starches type 3 (RS3) have been investigated with respect to their resistance to digestion, fermentability, and their effects on the composition and turnover of bile acids in rats. RSA (a mixture of retrograded maltodextrins and branched high molecular weight polymers), which is more resistant than RSB (a retrograded potato starch), increased the rate of fermentation accompanied by a decrease of pH in cecum, colon, and feces. Because they were bound to RS3, less bile acids were reabsorbed, resulting in a higher turnover through the large bowel. Because of the rise of volume, the bile acid level was unchanged and the formation of secondary bile acids was partly suppressed. The results proved a strong relation between RS3, short chain fatty acid production, and microflora. However, butyrate specific benefits are only achieved by an intake of RS3 that result in good fermentation properties, which depend on the kind of the resistant starch structures. 相似文献