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61.
Jonathan F. Bach Seth A. Glasser 《The Canadian veterinary journal. La revue veterinaire canadienne》2013,54(9):873-875
A 9-year-old castrated male Shetland sheepdog was diagnosed with necrolytic migratory erythema and hepatocutaneous syndrome. Necrolytic migratory erythema was treated with intermittent intravenous amino acids as needed to control cutaneous lesions. The addition of lipid infusions extended the treatment interval. The patient had a favorable response for 24 months. 相似文献
62.
Matthew R. Dzialak Dean J. Houchen Seth M. Harju James P. Mudd John J. Wondzell Stephen L. Webb Nicholas P. Gould Jennifer E. Hess Jeffrey B. Winstead 《Landscape Ecology》2013,28(7):1371-1385
Narrow endemism presents challenges to species occurrence modeling particularly when the distribution of key local habitat features changes across space and time as a function of processes operating at larger scales. One need facing conservation in such settings is a better understanding of the biogeographic dynamics of the larger features that govern occurrence of critical local habitat. The Mescalero–Monahans shinnery sands region of western North America is a dynamic landscape where sand shinnery oak interacts with wind-driven sand to establish dune habitat. This ecosystem supports several narrowly endemic dune-dwelling species including the dunes sagebrush lizard. Using near-anniversary satellite and aerial imagery from 1986, 1998, and 2011, we integrated object-based image classification and statistical analysis to develop and validate a spatially explicit estimate of the sand shinnery oak ecosystem, including dynamics associated with its attrition and emergence, at high resolution throughout an 89,849-km2 study area encompassing the range of the dunes sagebrush lizard. The spatial estimate of the distribution and extent of the sand shinnery oak soil-vegetation association validated reasonably well (overall accuracy = 0.79; sensitivity = 0.49; specificity = 0.91) and showed that the association declined 10.3 % in extent during the 25-year assessment window. The presence of sand shinnery oak, patch size, and patch isolation were dynamic across space and time; a regression model showed that smaller, isolated patches on the periphery of the system were more likely to be lost over time whereas larger, less isolated, and centrally distributed patches were more likely to persist or expand. This study details broadly applicable methods to accurately delineate landforms throughout large extents, and offers mapping tools specific to issues surrounding Mescalero–Monahans shinnery sands endemics that are readily amenable to testing, refinement, and application in efforts to focus sustainable landscape management including conservation of endemic species. 相似文献
63.
Seth Nii-Annang Holger Grünewald Dirk Freese Reinhard F. Hüttl Oliver Dilly 《Biology and Fertility of Soils》2009,45(5):531-538
The impact of alley cropping on post-lignite mine soils developing from quaternary deposits after 9 years of recultivation
was evaluated on the basis of microbial indicators, organic C and total N contents, and the isotope characteristics of soil
C. Soils were sampled at the 0 to 3, 3 to 10, and 10 to 30 cm depths under black locust (Robinia pseudoacacia L.), poplar (Populus spp.), the transition zone and in the middle of alley under rye (Secale cereale). There was no significant effect of vegetation on microbial properties presumably, due to the high variability, whereas organic
C and total N contents at the 0- to 3-cm layer were significantly higher under black locust and poplar than in the transition
zone and rye field. Organic C total N contents, and basal respiration, microbial biomass, and microbial quotient decreased
with soil depth. Soil organic C and total N contents were more than doubled after 9 years of recultivation, with annual C
and N accretion rate of 162 g C
org m−2 year−1 and 6 g N
t m−2 year−1. Microbial properties indicated that the soils are in early stages of development; the C isotope characteristics confirmed
that the sequestered C was predominantly from C3 plants of the alley cropping. 相似文献
64.
Extracts of roots of Rumex nepalensis, Berberis aristata, Arnebia benthamii, bark of Taxus wallichiana, Juglans regia and petals of Jacquinia ruscifolia were tested for their antifungal activity against twelve different fungal pathogens. Ethanolic extracts of R. nepalensis and J. ruscifolia extracts showed a broad spectrum of activity. 相似文献
65.
The effect of polydioxanone hemicerclage suture on the occurrence of fracture during tibial tuberosity advancement with an elongated bi‐directional hinged osteotomy
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69.
Malin Strand Martin Hedstr?m Henrik Seth Eric G. McEvoy Erik Jacobsson Ulf G?ransson H?kan S. Andersson Per Sundberg 《Marine drugs》2016,14(4)
We test previous claims that the bacteria Vibrio alginolyticus produces tetrodotoxin (TTX) when living in symbiosis with the nemertean Lineus longissimus by a setup with bacteria cultivation for TTX production. Toxicity experiments on the shore crab, Carcinus maenas, demonstrated the presence of a paralytic toxin, but evidence from LC-MS and electrophysiological measurements of voltage-gated sodium channel–dependent nerve conductance in male Wistar rat tissue showed conclusively that this effect did not originate from TTX. However, a compound of similar molecular weight was found, albeit apparently non-toxic, and with different LC retention time and MS/MS fragmentation pattern than those of TTX. We conclude that C. maenas paralysis and death likely emanate from a compound <5 kDa, and via a different mechanism of action than that of TTX. The similarity in mass between TTX and the Vibrio-produced low-molecular-weight, non-toxic compound invokes that thorough analysis is required when assessing TTX production. Based on our findings, we suggest that re-examination of some published claims of TTX production may be warranted. 相似文献
70.
Fiorenza Micheli Andrew O. Shelton Seth M. Bushinsky Alice L. Chiu Alison J. Haupt Kimberly W. Heiman Carrie V. Kappel Margaret C. Lynch Rebecca G. Martone Robert B. Dunbar James Watanabe 《Biological conservation》2008,141(4):1078-1090
We evaluated the persistence and possible recovery of two depleted marine mollusks, the red (Haliotis rufescens) and black abalone (H. cracherodii), in central California, USA. Monitoring over 32-years did not reveal increasing or decreasing trends in red abalone abundances and sizes over the past three decades, in the absence of harvesting. Comparisons between marine reserves protected for at least 25 years and sites with open public access showed significant difference in size structure for black abalone, with individuals greater than 8 cm in shell length comprising 14–37% of animals in reserves and 2–11% at open-access sites, and a trend for greater abundances of red abalone within reserves. Despite no increasing trends, protection in one of the no-take reserves, the Hopkins marine life refuge (HMLR), has led to persistence of red abalone populations over multiple generations, at average densities of 0.2 individuals/m2. At other locations, both within the HMLR and elsewhere, red abalone densities are lower than at the location where long-term studies were conducted (av. 0.03 animals/m2), and an order of magnitude lower than for black abalone (av. 0.4 animals/m2). These results suggest that continued fishery closure and protection in no-take reserves are effective tools for allowing persistence of abalone populations, though there are no signs of recovery to levels comparable to those preceding fisheries collapse. Such failure to recover is most likely associated with high natural mortality and possibly continued illegal take, but not with processes underlying low abalone population levels elsewhere, including food or habitat limitation, recruitment failure, or disease. Linking current structure and trends to specific processes is a crucial first step towards devising focused strategies for conserving and re-building depleted marine populations. 相似文献