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51.
John S. Munday Kristen A. Willis Matti Kiupel Fraser I. Hill Magdalena Dunowska 《Veterinary dermatology》2008,19(6):400-404
A 3‐year‐old cat from New Zealand developed three small raised non‐ulcerated plaques on the face. Serology detected antibodies against feline immunodeficiency virus (FIV). Histology of the plaque revealed epidermal hyperplasia with keratinocytes either distended with large blue‐grey cytoplasmic bodies or with shrunken nuclei surrounded by a clear halo. Papillomavirus (PV) antigen was detected immunohistochemically and feline viral plaque was diagnosed. Swabs were taken of both lesional and non‐lesional skin, and polymerase chain reactions were used to detect PV DNA. Three different PV DNA sequences were amplified, one from a Felis domesticus PV type 1 (FdPV‐1) previously amplified from a feline viral plaque, a second (FdPV‐JM) previously amplified from feline cutaneous squamous cell carcinomas, and a third FdPV‐MY that was not reported previously. All three sequences were amplified from swabs of both lesional and non‐lesional skin. These results extend the geographical range of FdPV‐1 outside North America and also demonstrate the ability of FdPV‐1 to asymptomatically infect feline skin. However, the detection of multiple PV sequences within both lesional and non‐lesional samples makes it difficult to determine whether or not any of the PVs caused feline viral plaque development in this cat. This is the first time PV DNA has been detected in a feline skin swab sample. Additionally, it is the first report of multiple PVs being detected in a single sample from a cat. This may suggest that FIV infection predisposes cats to cutaneous PV infection. 相似文献
52.
Advances in topical glaucoma therapy 总被引:1,自引:0,他引:1
Significant advances have recently been achieved in the development of topical glaucoma medications. The primary advantage of a topical preparation is the reduced incidence of adverse systemic effects attributable to a given drug compared to its systemically administered counterpart. However, the strong protective barrier of the eye forces topical ophthalmic preparations to be highly concentrated and in some cases, they have the potential to produce unwanted systemic effects, particularly in smaller animals. Oral carbonic anhydrase inhibitors are commonly associated with adverse effects in both humans and animals. Two recently developed topical carbonic anhydrase inhibitors, dorzolamide and brinzolamide, have shown promise in reducing intraocular pressure in animals and systemic side effects are apparently limited with their use. The topical alpha2-agonist apraclonidine, on the other hand, effectively reduces intraocular pressure in cats and dogs, but in its currently available form is likely to induce unwanted systemic effects. Latanoprost is a topical prostaglandin F2alpha analog that has proven effective in reducing intraocular pressure in dogs and horses, but while systemic side effects have not yet been reported, this topical preparation may exacerbate pre-existing or concurrent ocular inflammatory disease. 相似文献
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Expansion of flood irrigation in the Lower Macquarie Valley of New South Wales, Australia, has been suggested as a major
cause of increased groundwater recharge. The aim of this study was to estimate deep percolation under irrigation on two soils
in the valley, in order to infer groundwater recharge. Three methods were used; water balance, Darcian flux calculations and
chloride mass balance modelling. Chloride mass balance modelling and the water balance method gave comparable estimates of
deep percolation for each soil. Chloride mass balance modelling was identified as the most reliable method for estimating
deep percolation, but only gave an estimate for the entire growing season. These estimates were 214 and 104 mm for a cracking
clay and red brown earth, respectively. While there is potentially greater error associated with estimates obtained using
the water balance, this technique provided estimates of deep percolation for each individual irrigation. Results of the water
balance indicated that deep percolation was greatest early in the growing season, following initial wetting of the soil, when
the crop had a low leaf area index. Results calculated using Darcian flux equations were highly variable, and were therefore
unreliable estimates of deep percolation. Groundwater recharge, inferred from estimates of deep percolation determined with
the chloride mass balance model, was used to estimate the magnitude of potential annual groundwater rise. The potential groundwater
rise during the 1992/1993 cotton growing season ranged from 465 mm beneath the cracking clay to 267 mm under the red brown
earth. It is suggested that groundwater recharge and rise were highly dependent on the weather conditions prevailing during
this period.
Received: 24 January 1997 相似文献
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57.
A linear photodiode array has been used as the photodetector element in a new ultraviolet-visible detection system for high-performance liquid chromatography. This array allows simultaneous acquisition of light intensity data at all wavelengths between 190 and 600 nanometers. By use of a computer network concept in the electronics, this detection system can process eight different chromatographic signals simultaneously in real time and acquire spectra manually or automatically. Detector response times are variable and can be as low as 0.040 second, and bandwidth selection is variable from 4 to 400 nanometers. These characteristics permit fast chromatographic techniques and user-selectable signal-to-noise ratio enhancement. Spectra can be acquired in 10 milliseconds, permitting qualitative characterization at several different points on a single peak without destroying chromatographic signal integrity. Examples illustrate applications in fast high-performance liquid chromatography peak purity determination, and postanalysis data reduction. 相似文献
58.
Estimating the mass of asteroid 253 mathilde from tracking data during the NEAR flyby 总被引:1,自引:0,他引:1
DK Yeomans J Barriot DW Dunham RW Farquhar JD Giorgini CE Helfrich AS Konopliv JV McAdams JK Miller WM Owen DJ Scheeres SP Synnott BG Williams 《Science (New York, N.Y.)》1997,278(5346):2106-2109
The terminal navigation of the Near Earth Asteroid Rendezvous (NEAR) spacecraft during its close flyby of asteroid 253 Mathilde involved coordinated efforts to determine the heliocentric orbits of the spacecraft and Mathilde and then to determine the relative trajectory of the spacecraft with respect to Mathilde. The gravitational perturbation of Mathilde on the passing spacecraft was apparent in the spacecraft tracking data. As a result of the accurate targeting achieved, these data could be used to determine Mathilde's mass as 1.033 (+/- 0.044) x 10(20) grams. Coupled with a volume estimate provided by the NEAR imaging team, this mass suggests a low bulk density for Mathilde of 1.3 grams per cubic centimeter. 相似文献
59.
JK Harmon SJ Ostro LAM Benner KD Rosema RF Jurgens R Winkler DK Yeomans D Choate R Cormier JD Giorgini DL Mitchell PW Chodas R Rose D Kelley MA Slade ML Thomas 《Science (New York, N.Y.)》1997,278(5345):1921-1924
Radar observations of comet Hyakutake (C/1996 B2) made at the Goldstone Deep Space Communications Complex in California have detected echoes from the nucleus and from large grains in the inner coma. The nucleus of this bright comet was estimated to be only 2 to 3 kilometers in diameter. Models of the coma echo indicate backscatter from porous, centimeter-size grains ejected anisotropically at velocities of tens of meters per second. The radar observations suggest that a comet's activity may be a poor indicator of its size and provide evidence that large grains constitute an important component of the mass loss from a typical active comet. 相似文献
60.
Mass spawning in tropical reef corals 总被引:1,自引:0,他引:1
Harrison PL Babcock RC Bull GD Oliver JK Wallace CC Willis BL 《Science (New York, N.Y.)》1984,223(4641):1186-1189
Synchronous multispecific spawning by a total of 32 coral species occurred a few nights after late spring full moons in 1981 and 1982 at three locations on the Great Barrier Reef, Australia. The data invalidate the generalization that most corals have internally fertilized, brooded planula larvae. In every species observed, gametes were released; external fertilization and development then followed. The developmental rates of externally fertilized eggs and longevities of planulae indicate that planulae may be dispersed between reefs. 相似文献