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91.
Jedelská J Vogt A Reinscheid UM Keusgen M 《Journal of agricultural and food chemistry》2008,56(4):1465-1470
Three new sulfur-containing compounds were identified in Allium L. species belonging to the subgenus Melanocrommyum as the first examples of sulfur-containing pyrrole derivatives in nature. Some of these species are traditionally used in Southwest and Central Asia as vegetables and herbal drugs. A hypothetical biogenetic scheme is proposed in which L-(+)- S-(3-pyrrolyl)cysteine sulfoxide is enzymically degraded. The resulting 2-lactyl-3'-pyrrolyl sulfoxide is condensed readily to the red pigment 3,3'-dithio-2,2'-dipyrrole. All compounds are chemically unstable, rendering the analysis extremely difficult. Correlation NMR in combination with diffusion NMR allowed the identification of these low molecular weight compounds. For the first time, the compounds involved in the coloring process of Allium plant material have been identified from native plant material. 相似文献
92.
H A Swartz D W Vogt K A Michalski J E Warren D Kiesling 《American journal of veterinary research》1985,46(10):2145-2146
Chromosomes of a ewe lamb born with atresia ani vaginalis were examined after a 72-hour culture of peripheral whole blood. The 2n number of chromosomes was 54,XX, with no apparent deviation from normality. Pedigree analysis of the ewe lamb indicated that her sire and dam were only slightly related (Rsd = 0.59%); therefore, the amount of inbreeding of the lamb was small (Fx = 0.30%). 相似文献
93.
Schaller P Vogt HR Strasser M Nettleton PF Peterhans E Zanoni R 《Schweizer Archiv für Tierheilkunde》2000,142(4):145-153
3866 sheep from 226 flocks of breeding associations and 1218 sheep from 15 independent sheep owners were tested for the presence of serum antibodies against Maedi-Visna and Border Disease viruses. The flocks were randomly selected based on the relative proportion and the geographical distribution of the 4 predominant Swiss sheep breeds (Braunk?pfiges Fleischschaf, Schwarzbraunes Berg- und Juraschaf, Walliser Schwarznasenschaf, Weisses Alpenschaf). Additionally two smaller breeds were included in the study (Charollais Suisse, Milchschafe). Sera of all sheep older than 1 year were collected together with data characterizing host and management factors. The sera were tested using established ELISAs for detection of antibodies to Maedi-Visna and Bovine Virus Diarrhea/Border Disease viruses. ELISA results of Maedi-Visna serology were confirmed by immunoblotting. 9% of the sheep of breeding associations were antibody-positive for Maedi-Visna virus. The results of the different breeds varied between 0.4% and 36%. A multiple logistic regression procedure identified breed, age, airing in barns, herd size, pasturing on alps and way of keeping the animals during winter as associated factors with individual serostatus. The prevalence of antibodies to Border Disease was 20% in sheep of breeding associations and 65% in those of independent sheep owners. 相似文献
94.
Kurt H. Riitters Peter Vogt Pierre Soille Jacek Kozak Christine Estreguil 《Landscape Ecology》2007,22(7):1033-1043
Mathematical morphology encompasses methods for characterizing land-cover patterns in ecological research and biodiversity
assessments. This paper reports a neutral model analysis of patterns in the absence of a structuring ecological process, to
help set standards for comparing and interpreting patterns identified by mathematical morphology on real land-cover maps.
We considered six structural classes (core, perforated, edge, connector, branch, and patch) on randomly generated binary (forest,
non-forest) maps in which the percent occupancy (P) of forest varied from 1% to 99%. The maps were dominated by the patch
class for low P, by the branch and connector classes for intermediate P, and by the edge, perforated, and core classes for
high P. Two types of pattern phase changes were signaled by abrupt transitions among the six structural classes, at critical
P thresholds that were indicated by increased variance among maps for the same P. A phase change from maps dominated by the
patch class to maps dominated by the branch and connector classes was related to the existence of a percolating cluster of
forest, and the P threshold varied depending on the co-existence of the core class. A second phase change from the edge class
to the perforated class was related to the existence of a percolating cluster of non-core (including non-forest) and represents
a change of context from exterior to interior. Our results appear to be the first demonstration of multiple phase changes
controlling different aspects of landscape pattern on random neutral maps. Potential applications of the results are illustrated
by an analysis of ten real forest maps.
The U.S. Government's right to retain a non-exclusive, royalty-free license in and to any copyright is acknowledged. 相似文献
95.
David M.B. Cupples A.M. Lawrence G.B. Shi G. Vogt K. Wargo P.M. 《Water, air, and soil pollution》1998,105(1-2):183-192
The responses of temperate and boreal forest ecosystems to increased nitrogen (N) inputs have been varied, and the responses of soil N pools have been difficult to measure. In this study, fractions and pool sizes of N were determined in the forest floor of red spruce stands at four sites in the northeastern U.S. to evaluate the effect of increased N inputs on forest floor N. Two of the stands received 100 kg N ha-1 yr-1 for three years, one stand received 34 kg N ha-1 yr-1 for six years, and the remaining stand received only ambient N inputs. No differences in total N content or N fractions were measured in samples of the Oie and Oa horizons between treated and control plots in the three sites that received N amendments. The predominant N fraction in these samples was amino acid N (31-45% of total N), followed by hydrolyzable unidentified N (16-31% of total N), acid-soluble N (18-22% of total N), and NH4 + (9-13% of total N). Rates of atmospheric deposition varied greatly among the four stands. Ammonium N and amino acid N concentrations in the Oie horizon were positively related to wet N deposition, with respective r2 values of 0.92 and 0.94 (n = 4, p < 0.05). These relationships were somewhat stronger than that observed between atmospheric wet N deposition and total N content of the forest floor, suggesting that these pools retain atmospherically deposited N. The NH4 + pool may represent atmospherically deposited N that is incorporated into organic matter, whereas the amino acid N pool could result from microbial immobilization of atmospheric N inputs. The response of forest floor N pools to applications of N may be masked, possibly by the large soil N pool, which has been increased by the long-term input of N from atmospheric deposition, thereby overwhelming the short-term treatments. 相似文献
96.
Claudia Cruz Villagrn Debora Vogt Ashish Gupta Enrique Aburto Fernndez 《The Canadian veterinary journal. La revue veterinaire canadienne》2021,62(11):1190
A 3-year-old Quarter Horse gelding was evaluated for chronic weight loss, diarrhea, and pruritus. Physical examination revealed several ulcerative lesions on the skin and mucosal membranes. Diagnostic imaging findings were consistent with enteritis, typhlitis, and colitis. Multisystemic eosinophilic epitheliotropic disease (MEED) was diagnosed upon necropsy. This disease may be considered a form of equine inflammatory bowel disease complex which can be challenging to diagnose, requiring histological assessment, and in some cases, the use of immunohistochemical markers.Key clinical message:Multisystemic eosinophilic epitheliotropic disease is challenging to diagnose but should be considered in horses with chronic weight loss that fail to respond to conventional treatment for concurrent diarrhea and skin lesions. 相似文献
97.
98.
Lorenz I Vogt S 《Journal of veterinary medicine. A, Physiology, pathology, clinical medicine》2006,53(9):490-494
The objective of this prospective study was to elucidate whether amounts of bicarbonate needed for correction of acidosis and normalization of clinical signs are influenced by blood D-lactate concentrations in calves with diarrhoea. In 73 calves up to 3 weeks old with acute diarrhoea and base excess values below -10 mmol/l correction of acidosis was carried out within 3.5-h by intravenous administration of an amount of sodium bicarbonate which was calculated using the formula: HCO (mmol) = body mass (kg) x base deficit (mmol/l) x 0.6 (l/kg). Clinical signs, venous base excess, and plasma D-lactate concentrations were monitored immediately following admission, following correction of acidosis at 4 h and 24 h after admission. The base excess and plasma D-lactate concentrations throughout the study were -17.8 +/- 4.0, -0.4 +/- 0.4, -3.0 +/- 5.5 mmol/l (base excess), and 10.0 +/- 4.9, 9.8 +/- 4.8, 5.4 +/- 3.4 mmol/l (D-lactate) for the three times of examination. Metabolic acidosis was not corrected in more than half of the calves (n = 43) by the calculated amount of bicarbonate, whereas the risk of failure to correct acidosis increases with D-lactate concentrations. The study shows that calves with elevated D-lactate concentrations do not need additional specific therapy, as D-lactate concentrations regularly fall following correction of acidosis and restitution of body fluid volume, for reasons that remain unclear. However, calves with distinct changes in posture and demeanour need higher doses of bicarbonate than calculated with the factor of 0.6 in the formula mentioned above probably because of D-hyperlactataemia. 相似文献
99.
Bartges J Boynton B Vogt AH Krauter E Lambrecht K Svec R Thompson S 《Journal of the American Animal Hospital Association》2012,48(1):1-11
Guidelines are offered to guide the veterinary practitioner in designing a comprehensive, individualized wellness plan for each stage of a dog's life. Life stages are defined by both age and breed characteristics for practical purposes. Each patient visit should use an individualized approach to patient handling, preventive care, and early disease detection. Environment, behavior, nutrition, parasite control, vaccinations, dental care, zoonotic disease control, safety, and reproductive health should be addressed. 相似文献
100.