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排序方式: 共有255条查询结果,搜索用时 15 毫秒
81.
S Withrow M DeAngelis S Arnoczky H Rosen 《Journal of the American Veterinary Medical Association》1976,168(2):122-124
Of 27 dogs with fractures of the tibial tuberosity, 24 were treated by various methods of open reduction. Follow-up examination was obtained in 21 cases, and it was found that all but one fracture healed in 8 weeks. Tension band wiring and single interfragmentary screws were most commonly used; healing was similar in both groups. 相似文献
82.
Westmoreland SV Rosen J MacKey J Romsey C Xia DL Visvesvera GS Mansfield KG 《Veterinary pathology》2004,41(4):398-404
Free-living amoebae of the genus Acanthamoeba can cause a fatal disease of the brain in humans called granulomatous amoebic encephalitis. We present a case of meningoencephalitis and pneumonitis in a simian immunodeficiency virus (SIV)-infected rhesus macaque caused by Acanthamoeba sp. The animal became ill 176 days after intravenous inoculation with SIVmac251 after a short history of weight loss and a sudden onset of hind limb paresis and abnormal head movements. Histopathologic examination of hematoxylin and eosin-stained tissues revealed multifocal to coalescing necrotizing neutrophilic meningoencephalitis and pneumonitis. Immunofluorescence and polymerase chain reaction were used to identify the genus of amoeba as Acanthamoeba. Immunohistochemistry of immune cell markers was used to characterize the animal's immune response to the opportunistic amoebic infection with features of both innate and adaptive cell-mediated immunity. Although not previously reported, the potential transmission to humans, either through environmental contamination or contact with an infected animal, makes this disease a threat to laboratory animal care staff and pathologists. 相似文献
83.
Rosen SD 《The Veterinary record》2004,154(24):759-765
The Government recently announced that it intends to reject a recommendation by the Farm Animal Welfare Council that all animals should be stunned before slaughter (see VR, April 10, p 446). In this Viewpoint article, Dr Stuart Rosen discusses physiological aspects of Shechita, the Jewish method of religious animal slaughter. He outlines the religious context and describes the act of Shechita. He discusses the scientific literature on the behavioural responses to Shechita as well as neurophysiological studies relevant to the assessment of pain, and concludes that Shechita is a painless and humane method of animal slaughter. 相似文献
84.
85.
Tyler GL Sweetnam DN Anderson JD Borutzki SE Campbell JK Eshleman VR Gresh DL Gurrola EM Hinson DP Kawashima N Kursinski ER Levy GS Lindal GF Lyons JR Marouf EA Rosen PA Simpson RA Wood GE 《Science (New York, N.Y.)》1989,246(4936):1466-1473
The Voyager 2 encounter with the Neptune system included radio science investigations of the masses and densities of Neptune and Triton, the low-order gravitational harmonics of Neptune, the vertical structures of the atmospheres and ionospheres of Neptune and Triton, the composition of the atmosphere of Neptune, and characteristics of ring material. Demanding experimental requirements were met successfully, and study of the large store of collected data has begun. The initial search of the data revealed no detectable effects of ring material with optical depth tau [unknown] 0.01. Preliminary representative results include the following: 1.0243 x 10(26) and 2.141 x 10(22) kilograms for the masses of Neptune and Triton; 1640 and 2054 kilograms per cubic meter for their respective densities; 1355 +/- 7 kilometers, provisionally, for the radius of Triton; and J(2) = 3411 +/- 10(x 10(-6)) and J(4) = -26(+12)(-20)(x10(-6)) for Neptune's gravity field (J>(2) and J(4) are harmonic coefficients of the gravity field). The equatorial and polar radii of Neptune are 24,764 +/- 20 and 24,340 +/- 30 kllometers, respectively, at the 10(5)-pascal (1 bar) pressure level. Neptune's atmosphere was probed to a pressure level of about 5 x 10(5) pascals, and effects of a methane cloud region and probable ammonia absorption below the cloud are evident in the data. Results for the mixing ratios of helium and ammonia are still being investigated; the methane abundance below the clouds is at least 1 percent by volume. Derived temperature-pressure profiles to 1.2 x 10(5) pascals and 78 kelvins (K) show a lapse rate corresponding to "frozen" equilibrium of the para- and ortho-hydrogen states. Neptune's ionosphere exhibits an extended topside at a temperature of 950 +/- 160 K if H(+) is the dominant ion, and narrow ionization layers of the type previously seen at the other three giant planets. Triton has a dense ionosphere with a peak electron concentration of 46 x 10(9) per cubic meter at an altitude of 340 kilometers measured during occultation egress. Its topside plasma temperature is about 80 +/- 16 K if N(2)(+) is the principal ion. The tenuous neutral atmosphere of Triton produced distinct signatures in the occultation data; however, the accuracy of the measurements is limited by uncertainties in the frequency of the spacecraft reference oscillator. Preliminary values for the surface pressure of 1.6 +/- 0.3 pascals and an equivalent isothermal temperature of 48 +/- 5 K are suggested, on the assumption that molecular nitrogen dominates the atmosphere. The radio data may be showing the effects of a thermal inversion near the surface; this and other evidence imply that the Triton atmosphere is controlled by vapor-pressure equilibrium with surface ices, at a temperature of 38 K and a methane mixing ratio of about 10(-4). 相似文献
86.
Climate Change During the Last Deglaciation in Antarctica 总被引:1,自引:0,他引:1
PA Mayewski MS Twickler SI Whitlow LD Meeker Q Yang J Thomas K Kreutz PM Grootes DL Morse EJ Steig ED Waddington ES Saltzman P Whung KC Taylor 《Science (New York, N.Y.)》1996,272(5268):1636-1638
Greenland ice core records provide clear evidence of rapid changes in climate in a variety of climate indicators. In this work, rapid climate change events in the Northern and Southern hemispheres are compared on the basis of an examination of changes in atmospheric circulation developed from two ice cores. High-resolution glaciochemical series, covering the period 10,000 to 16,000 years ago, from a central Greenland ice core and a new site in east Antarctica display similar variability. These findings suggest that rapid climate change events occur more frequently in Antarctica than previously demonstrated. 相似文献
87.
The most prominent oscillatory feature observed in the Voyager 1 radio occultation of Saturn's rings is identified as a one-armed spiral bending wave excited by Titan's -1:0 nodal inner vertical resonance. Ring partides in a bending wave move in coherently inclined orbits, warping the local mean plane of the rings. The Titan -1:0 wave is the only known bending wave that propagates outward, away from Saturn, and the only spiral wave yet observed in which the wave pattern rotates opposite to the orbital direction of the ring particles. It is also the first bending wave identified in ring C. Modeling the observed feature with existing bending wave theory gives a surface mass density of approximately 0.4 g/cm(2) outside the wave region and a local ring thickness of [unknown]5 meters, and suggests that surface mass density is not constant in the wave region. 相似文献
88.
Rosen BA Salehi-Khojin A Thorson MR Zhu W Whipple DT Kenis PJ Masel RI 《Science (New York, N.Y.)》2011,334(6056):643-644
Electroreduction of carbon dioxide (CO(2))--a key component of artificial photosynthesis--has largely been stymied by the impractically high overpotentials necessary to drive the process. We report an electrocatalytic system that reduces CO(2) to carbon monoxide (CO) at overpotentials below 0.2 volt. The system relies on an ionic liquid electrolyte to lower the energy of the (CO(2))(-) intermediate, most likely by complexation, and thereby lower the initial reduction barrier. The silver cathode then catalyzes formation of the final products. Formation of gaseous CO is first observed at an applied voltage of 1.5 volts, just slightly above the minimum (i.e., equilibrium) voltage of 1.33 volts. The system continued producing CO for at least 7 hours at Faradaic efficiencies greater than 96%. 相似文献
89.
90.
Beta-1C-globulin: metabolism in glomerulonephritis 总被引:9,自引:0,他引:9
The metabolism of beta(1C)-globulin labeled with iodine-131 was studied in six normal individuals and in three individuals with glomerulonephritis who exhibited markedly reduced serum concentrations of this protein. Fractional of serum beta(1C)-globulin in glomerulonephritis appears to be chiefly secondary to decreased synthesis. 相似文献