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21.
OBJECTIVE: To evaluate characteristics of a large epidemic of sporotrichosis in cats. DESIGN: Retrospective study. ANIMALS: 347 cats with naturally acquired infection with Sporothrix schenckii. PROCEDURE: Medical records were reviewed for data regarding clinical, mycologic, histopathologic, and routine hematologic and serum biochemical findings; assays for FIV-specific antibodies and FeLV antigen; antifungal treatment; and follow-up. RESULTS: Lesions varied from small papules to extensive zones of necrosis.Ten cats had no skin lesions, 114 had skin lesions at a single site, 86 had skin lesions in 2 sites, and 137 had skin lesions in 3 or more sites. Respiratory tract signs were observed in 154 cats and were the most frequent extracutaneous sign. Anemia, leukocytosis with neutrophilia, hypoalbuminemia, and hyperglobulinemia were the main blood abnormalities. Antibodies against FIV were detected in 28 cats, FeLV antigen was detected in 2 cats, and both were detected in 1 cat among 142 cats tested. During the study, 118 cats were lost to follow-up and 124 died. Of 266 cats that were treated, 68 were cured. Complete healing of the lesions was observed regardless of the presence of extracutaneous signs, general condition, treatment schedule, or coinfection with FIV. CONCLUSIONS AND CLINICAL RELEVANCE: Feline sporotrichosis was evident in subclinical to severe forms; however, cats can respond well to regular and prolonged antifungal treatment.  相似文献   
22.
Acid hydrolysis, acid methanolysis, and enzymatic hydrolysis were compared for depolymerization of five different plant materials containing uronic acids. The analyzed plant materials were oat spelt, wheat straw, spruce thermomechanical pulp, aspen stemwood, and totally chlorine-free (TCF) bleached hardwood kraft pulp. Furthermore, GC (using both HP-1 and HP-5 capillary columns and FID and MSD detectors), HPAEC-PAD, and HPAEC-Borate techniques were compared for subsequent analysis of the released monosaccharides. It was shown that acid methanolysis combined with GC analysis is a convenient method for obtaining the sugar unit composition and amount of non-crystalline polysaccharides in different plant materials. The methanolysis method was generally superior to the hydrolysis method for xylan- and uronic acid-containing samples. However, acid and enzymatic hydrolysis showed the highest recoveries for bleached chemical pulp samples. Acid hydrolysis is also required for crystalline polysaccharides, but the strong acid conditions evidently lead to degradation of labile sugars. The plant methanolysates were not suitable as such for analysis on an HPAEC-PAD system. For analysis of the total amount of sugar units, hence including cellulose, other non-crystalline hemicelluloses, and pectins, a combination of the methanolysis and hydrolysis methods is recommended.  相似文献   
23.
Forest fires in mountainous areas can cause severe deforestation which can potentially trigger secondary natural hazards like debris falls and avalanches.We documented an extreme case study for the range of possible post-fire land cover(LC)dynamics.We investigated a 15-ha,steep(10°-65°)burnt slope in Styria(Austria)at elevation of 760-1130m,which burned in 1946 and has not fully recovered to date.Seven8-class legend LC maps were produced(1954,1966,1973,1982,1998,2004,2009)and integrated in a vector-based GIS,mainly by on-screen interpretation of aerial photos.Our aim was to clarify how post-wildfire LC dynamics take place on a severely damaged,steep slope and to give a basic projection of the future vegetation recovery process.The pre-fire Pinus sylvestris stands have been mainly replaced by Picea abies and Larix decidua.Regeneration proceeded mainly from the base of the slope upwards.All tree species together still cover no more than 40%of the slope after more than 60 years of recovery,while grassland communities and rock/debris areas have expanded.Multitemporal analysis showed a slow but steady increase in woodland cover.Degraded rock/debris areas,however,expanded as well because soil erosion and related debris flows remained active.Slope angle(with a threshold value of approx.35-40°)seemed to control whether erosion or regeneration prevailed.According to a simple extrapolation,the slope will not reach its former condition before 2070.This extreme disturbance window of more than 120 years is owed to the steepness of the slope and to the shallow soils on dolomitic bedrock that were severely damaged by the fire.The neglect of any game fencing is a further factor slowing regeneration.  相似文献   
24.
25.
The spindle assembly checkpoint guards the fidelity of chromosome segregation. It requires the close cooperation of cell cycle regulatory proteins and cytoskeletal elements to sense spindle integrity. The role of the centrosome, the organizing center of the microtubule cytoskeleton, in the spindle checkpoint is unclear. We found that the molecular requirements for a functional spindle checkpoint included components of the large gamma-tubulin ring complex (gamma-TuRC). However, their localization at the centrosome and centrosome integrity were not essential for this function. Thus, the spindle checkpoint can be activated at the level of microtubule nucleation.  相似文献   
26.
Two new fatty acid glucosides, (3E,8Z)-8-carboxy-1-(O-beta-D-glucopyranosyl)-2,6-dihydroxytritriaconta-3,8-diene (1) and (8Z)-8-carboxy-1-(O-beta-D-glucopyranosyl)-3,4-epoxy-2,6-dihydroxytritriacont-8-ene (2), have been isolated from the root bark of Ochna calodendron and their structures elucidated by extensive two-dimensional NMR methods including HMQC, HMBC and NOESY experiments.  相似文献   
27.
Summary

High yield and quality are important factors for growers of carrots (Daucus carota L.). The objective of this study was to determine optimum soil moisture and N-fertilization to maximize carrot yield and external quality (i.e. the quantity of split and forked roots). The experiment was carried out in a microplot field installation with three levels of soil moisture (75, 50 and 25 vol% available field capacity (AFC)) on a sandy and a loamy soil over the last 16 and 11 weeks of the cropping period, respectively. Two movable roofs covered with polyethylene foil were used to maintain the three soil moisture levels, which were measured in all combinations with two levels of nitrogen fertilization (0 and 150 kg N ha-1). The highest total yields were reached at both soil types at 75 vol% AFC and 150 kg N ha-1. The quantity of forked carrots was more affected by reduced soil moisture on the sandy soil than on the loamy soil. The mass fraction of split roots increased with increasing soil moisture on both soil types and a significant interaction was calculated between soil type and fertilization. The mass of split roots on the sandy soil was significantly increased by fertilization.  相似文献   
28.
Common bean (Phaseolus vulgaris L.) is an important legume crop worldwide. The International Centre for Tropical Agriculture (CIAT) and its national partners in Africa aim to overcome production constraints of common bean and address the food, nutrition needs and market demands through development of multitrait bean varieties. Breeding is guided by principles of market‐driven approaches to develop client‐demanded varieties. Germplasm accessions from especially two sister species, P. coccineus and P. acutifolius, have been utilized as sources of resistance to major production constraints and interspecific lines deployed. Elucidation of plant mechanisms governing pest and disease resistance, abiotic stress tolerance and grain nutritional quality guides the selection methods used by the breeders. Molecular markers are used to select for resistance to key diseases and insect pests. Efforts have been made to utilize modern genomic tools to increase scale, efficiency, accuracy and speed of breeding. Through gender‐responsive participatory variety selection, market‐demanded varieties have been released in several African countries. These new bean varieties are a key component of sustainable food systems in the tropics.  相似文献   
29.
Niobium-92 (92Nb) decays to zirconium-92 (92Zr) with a half-life of 36 million years and can be used to place constraints on the site of p-process nucleosynthesis and the timing of early solar system processes. Recent results have suggested that the initial 92Nb/93Nb of the solar system was high (>10(-3)). We report Nb-Zr internal isochrons for the ordinary chondrite Estacado (H6) and a clast of the mesosiderite Vaca Muerta, both of which define an initial 92Nb/93Nb ratio of approximately 10(-5). Therefore, the solar system appears to have started with a ratio of <3 x 10(-5), which implies that Earth's initial differentiation need not have been as protracted as recently suggested.  相似文献   
30.
Für Brokkoli wird zum Kulturbeginn ein Nmin‐Angebot von mehr als 100 kg N/ha empfohlen, obwohl die N‐Aufnahme bis zum 20. Kulturtag nur etwa 20 kg N/ha beträgt. Mit Hilfe der Gamma‐Scanning‐Technik wurde die Wirkung eines variierten Nmin‐Ange‐bots auf das Wachstum zerstörungsfrei gemessen.

Zur Pflanzung wurde eine N‐Düngung von 50, 100 bzw. 150 kg N/ha und zum Zeitpunkt beginnender Wachstumsminderung Kopfdüngungen von 250, 200 bzw. 150 kg N/ha (bei einheitlichem Gesamt‐Nmin‐Angebot von 300 kg N/ha) gegeben. Zur Ernte führte nur das niedrigste Nmin‐Angebot zur Pflanzung zu einer signifikant geringeren Gesamtmasse—nicht jedoch beim Marktertrag.

Wurden zur Pflanzung unterschiedliche Nmin‐Angebote durch Düngung von 5, 55 bzw. 105 kg N/ha eingestellt und während des Wachstums die Pflanzen einheitlich mit 5 Kopfdüngungen in Höhe von 15, 50, 60, 90 und 80 kg N/ha in 10 Tage‐Intervallen versorgt, so bildeten nur die Pflanzen zur Ernte, die mit 5 kg N/ha zur Pflanzung gedüngt wurden, eine signifikant niedrigere Gesamtmasse aus. Die Behandlungen hatten wiederum keinen signifikanten Einfluß auf die Höhe der Markterträge.

Danach könnte mit einem Nmin‐Angebot von unter 100 kg N/ha zur Pflanzung und mehreren Kopfdüngungen entsprechend der N‐Aufnahme durch die Pflanzen hohe Erträge erzielt und gleichzeitig das Risiko für die N‐Auswaschung auf Sandboden reduziert werden.  相似文献   
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