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Human papillomavirus type 27: detection of a novel human papillomavirus in common warts of a renal transplant recipient. 总被引:2,自引:1,他引:1 下载免费PDF全文
The cloning and partial characterization of the genome of human papillomavirus type 27 (HPV-27) is described. Hybridization analyses reveal that this is a new HPV type, with the strongest homology to HPV-2. 相似文献
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Crystallia ribonuclease has no marked proteolytic activity, since digestion of sections with this enzyme produces no appreciable decrease in the intensity of the cytochemical tests for arginine and tyrosine. Cytoplasmic basophilia is unaffected by treatment with cold trichloracetic acid or with boiling alcohol-ether mixture. Mononucleotides and fatty acids thus have nothing to do with basophilia. Digestion of sections with desoryribonuclease has no effect on the alkaline phosphatase or arginine tests, while it supresses the Feulgen reaction and the affinity of the chromatin for basic and for some acid dyes. 相似文献
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Luning Wang Mikko J. Nissi Ferenc Tóth Jonah Shaver Casey P. Johnson Jinjin Zhang Michael Garwood Cathy S. Carlson Jutta M. Ellermann 《PloS one》2015,10(10)
Purpose
To evaluate multiple MRI parameters in a surgical model of osteochondrosis (OC) in goats.Methods
Focal ischemic lesions of two different sizes were induced in the epiphyseal cartilage of the medial femoral condyles of goats at 4 days of age by surgical transection of cartilage canal blood vessels. Goats were euthanized and specimens harvested 3, 4, 5, 6, 9 and 10 weeks post-op. Ex vivo MRI scans were conducted at 9.4 Tesla for mapping the T1, T2, T1ρ, adiabatic T1ρ and TRAFF relaxation times of articular cartilage, unaffected epiphyseal cartilage, and epiphyseal cartilage within the area of the induced lesion. After MRI scans, safranin O staining was conducted to validate areas of ischemic necrosis induced in the medial femoral condyles of six goats, and to allow comparison of MRI findings with the semi-quantitative proteoglycan assessment in corresponding safranin O-stained histological sections.Results
All relaxation time constants differentiated normal epiphyseal cartilage from lesions of ischemic cartilage necrosis, and the histological staining results confirmed the proteoglycan (PG) loss in the areas of ischemia. In the scanned specimens, all of the measured relaxation time constants were higher in the articular than in the normal epiphyseal cartilage, consistently allowing differentiation between these two tissues.Conclusions
Multiparametric MRI provided a sensitive approach to discriminate between necrotic and viable epiphyseal cartilage and between articular and epiphyseal cartilage, which may be useful for diagnosing and monitoring OC lesions and, potentially, for assessing effectiveness of treatment interventions. 相似文献8.
CRAIG R. WHITE DAVID BOERTMANN DAVID GRÉMILLET PATRICK J. BUTLER JONATHAN A. GREEN GRAHAM R. MARTIN 《Ibis》2011,153(1):170-174
Arctic seas have warmed and sea ice has retreated. This has resulted in range contraction and population declines in some species, but it could potentially be a boon for others. Great Cormorants Phalacrocorax carbo have a partially wettable plumage and seem poorly suited to foraging in Arctic waters. We show that rates of population change of Cormorant colonies around Disko Bay, Greenland, are positively correlated with sea surface temperature, suggesting that they may benefit from a warming Arctic. However, although Cormorant populations may increase in response to Arctic warming, the extent of expansion of their winter range may ultimately be limited by other factors, such as sensory constraints on foraging behaviour during long Arctic nights. 相似文献
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Calanus finmarchicus is a key‐structural species of the North Atlantic polar biome. The species plays an important trophic role in subpolar and polar ecosystems as a grazer of phytoplankton and as a prey for higher trophic levels such as the larval stages of many fish species. Here, we used a recently developed ecological niche model to assess the ecological niche (sensu Hutchinson) of C. finmarchicus and characterize its spatial distribution. This model explained about 65% of the total variance of the observed spatial distribution inferred from an independent dataset (data of the continuous plankton recorder survey). Comparisons with other types of models (structured population and ecophysiological models) revealed a clear similarity between modeled spatial distributions at the scale of the North Atlantic. Contemporary models coupled with future projections indicated a progressive reduction of the spatial habitat of the species at the southern edge and a more pronounced one in the Georges Bank, the Scotian Shelf and the North Sea and a potential increase in abundance at the northern edge of its spatial distribution, especially in the Barents Sea. These major changes will probably lead to a major alteration of the trophodynamics of North Atlantic ecosystems affecting the trophodynamics and the biological carbon pump. 相似文献
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Our objective was to determine how varied is the response of C cycling to temperature and irradiance in tundra vegetation. We used a large chamber to measure C exchange
at 23 locations within a small arctic catchment in Alaska during summer 2003 and 2004. At each location, we determined light
response curves of C exchange using shade cloths, twice during a growing season. We used data to fit a simple photosynthesis-irradiance,
respiration-temperature model, with four parameters. We used a maximum likelihood technique to determine the acceptable parameter
space for each light curve, given measurement uncertainty. We then explored which sites and time periods had parameter sets
in common—an indication of functional similarity. We found that seven distinct parameter sets were required to explain observed
C flux responses to temperature and light variation at all sites and time periods. The variation in estimated maximum photosynthetic
rate (Pmax) was strongly correlated with measurements of site leaf area index (LAI). The behavior of tussock tundra sites, the dominant
vegetation of arctic tundra, could largely be described with a single parameter set, with a Pmax of 9.7 μmol m−2 s−1. Tussock tundra sites had, correspondingly, similar LAI (mean = 0.66). Non-tussock sites (for example, sedge and shrub tundras)
had larger spatial and temporal variations in both C dynamic parameters (Pmax varying from 9.7–25.7 μmol m−2 s−1) and LAI (0.6–2.0). There were no clear relationships between dominant non-tussock vegetation types and a particular parameter
set. Our results suggest that C dynamics of the acidic tussock tundra slopes and hilltops in northern Alaska are relatively
simply described during the peak growing season. However, the foot-slopes and water tracks have more variable patterns of
LAI and C exchange, not simply related to the dominant vegetation type. 相似文献