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71.
LC Hudson D Weinstock T Jordan NO Bold-Fletcher 《Canadian Metallurgical Quarterly》1996,43(5):277-285
Twelve naive and nine test-vaccinated horses which developed clinical signs of rabies as a result of the required protocol of a vaccine trial were prospectively observed. Nineteen of the 21 cases were confirmed positive for rabies infection of the brain by fluorescent antibody test. The two horses with negative results had ganglioneuritis of the trigeminal ganglion or lymphocytic perivascular cuffing in the brain stem in addition to clinical signs. Average incubation period was 12.3 days and average morbidity was 5.5 days. Naive animals had significantly shorter incubation and morbidity periods (P < 0.05). Muzzle tremors were the most frequently observed (81%) and most common initial sign. Other common signs were pharyngeal spasm or pharyngeal paresis (71%), ataxia or paresis (71%), lethargy or somnolence (71%). The furious form was manifested in 43% of rabid horses and some of these furious animals initially manifested the dumb form. The paralytic form was not observed. Histopathology was characteristics for rabies. The results of this trial do not reflect on the efficacy of commercially licensed equine rabies vaccines. 相似文献
72.
BL King G Sirugo JH Nadeau TJ Hudson KK Kidd BM Kacinski M Schalling 《Canadian Metallurgical Quarterly》1998,9(5):392-393
BACKGROUND: Accommodation-convergence spasm (spasm of the near reflex) is usually bilateral, resulting in increased myopia, convergence, and miosis. Unilateral spasm of accommodation has rarely been reported. PATIENTS: We investigated three females (age range 10-19 years) referred for investigations of retrobulbar optic neuritis (2 cases) and decompensated esophoria (1 case). RESULTS: They all presented unilateral spasm of accommodation with visual loss due to increased myopia (-3.5 to -11.75 diopters). Apart from that, results of neuro-ophthalmological examination were normal. CONCLUSIONS: Unilateral accommodation spasm is rare and can mimic retrobulbar optic neuritis and convergent strabismus. The three components of the accommodation-convergence spasm may not always be present simultaneously. Recognizing such an entity is important to prevent the patient from useless, costful and potentially harmful investigations. 相似文献
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Quinlan P. Crowley P. Chanca M. Hudson S. Hunt B. Mulvaney K. Retz G. O'Sullivan C.E. Walsh P. 《Solid-State Circuits, IEEE Journal of》2004,39(12):2297-2310
A fully integrated transceiver suitable for low-data-rate wireless telemetry and sensor networks operating in the license-free ISM frequency bands at 433, 868, or 915 MHz implemented in 0.25-/spl mu/m CMOS is presented. G/FSK, ASK, and OOK modulation formats are supported at data rates from 0.3 to 200 kb/s. The transceiver's analog building blocks include a low-noise amplifier, mixer, channel filter, received signal-strength indication, frequency synthesizer, voltage-controlled oscillator, and power amplifier. FSK demodulation is implemented using a novel digital complex-frequency correlator that operates over a wide modulation-index range and approximates matched filter detection performance. Automatic gain control, automatic frequency control, and symbol timing recovery loops are included on chip. Operating in the 915-MHz band in FSK mode at 9.6 kb/s, the receiver consumes 19.7 mA from a 3-V supply and achieves a sensitivity of -112.8dBm at 0.1% BER. The transmitter consumes 28.5 mA for an output power of 10 dBm and delivers up to 14 dBm. 相似文献
75.
Ward C. Smith M. Jeffries A. Adams D. Hudson J. 《Electronics & Communication Engineering Journal》1996,8(4):191-200
Cellular communications have become the success story of the late 20th century. In just 15 years the global cellular subscriber base has grown to 60 million and it is forecast to exceed 350 million by early next century. This rapid growth has created the dichotomy for cellular operators of increasing pressure from customers to improve coverage, capacity and quality within their networks whilst the ever growing competition in the cellular marketplace demands that operational costs be reduced to the lowest possible level. One development which can assist network operators in reconciling these conflicting demands is the smart antenna. However, the successful deployment of smart antennas will require a much greater understanding of the characteristics of signals within the mobile/base-station transmission path. The measurement equipment described in this paper has enabled the acquisition of data which contributes significantly towards the understanding of these propagation path characteristics 相似文献
76.
While it is known that mice with genetic immune defects are useful for establishing durable engraftment of human tumor xenografts, the relative role of components of host innate and adoptive immunity in engraftment has not been determined. We directly compared the ability of four strains of genetically immunodeficient mice (NOD/SCID, SCID, Nude and Rag-1-deficient) to successfully engraft and support the human cell lines Daudi, Raji, Namalwa and Molt-4 as subcutaneous tumors. We additionally examined the effect of further immunosuppression of the mice by whole body irradiation at a dose of 600 cGy for Nude and Rag-1 and 300 cGy for SCID mice and by administration of anti-natural killer (asialo-GM1) antibody on tumor growth. Mice with each of the defects supported xenografts to varying degrees. We found differences in growth characteristics in the cell lines tested, with Namalwa consistently producing the largest tumors. With all cell lines studied, optimal growth was achieved using NOD/SCID mice. Overall, tumor growth was somewhat enhanced by pretreatment with radiation with little additional benefit from the addition of anti-asialo-GM1 antibody. The importance of multiple components of the innate and adoptive immune system in xenotransplantation were best demonstrated when results in untreated NOD/SCID mice were compared to SCID, nude and RAG-1-deficient mice. The NOD/SCID mouse with or without additional immunosuppression provides the optimal model for the study of the biology and treatment of human leukemias and lymphomas. 相似文献
77.
T Hudson 《Canadian Metallurgical Quarterly》1997,71(19):62-4, 66
Wall street's starry-eyed infatuation with practice management companies is gone, causing a market correction that's deflated stock multiples and slowed acquisitions. But don't write off the romance yet. 相似文献
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The popularity of the finite-difference time-domain (FDTD) method stems from the fact that it is not limited to a specific geometry and it does not restrict the constitutive parameters of a scatterer. Furthermore, it provides a direct solution to problems with transient illumination, but can also be used for harmonic analysis. However, researchers have limited their investigation to materials that are either isotropic or that have diagonal permittivity, conductivity, and permeability tensors. The authors derive the necessary extension to the FDTD equations to accommodate nondiagonal tensors. Excellent agreement between FDTD and exact analytic results is obtained for a one-dimensional anisotropic scatterer 相似文献