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排序方式: 共有392条查询结果,搜索用时 31 毫秒
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Dueger EL George LW Angelos JA Tankersley NS Luiz KM Meyer JA Portis ES Lucas MJ 《American journal of veterinary research》2004,65(9):1185-1188
OBJECTIVE: To evaluate the efficacy of ceftiofur crystalline-free acid (CCFA) administered into the posterior aspect of an ear for treatment of corneal ulceration associated with naturally occurring infectious bovine keratoconjunctivitis (IBK). ANIMALS: 78 beef calves located at Sierra Foothills Field Station (SFS) and 52 calves located at a commercial dairy (CD). All calves were from 3 to 9 months old. PROCEDURE: At each site, calves were randomly allocated to 1 of 2 treatment groups by use of a block design determined by corneal ulcer size. A single dose of CCFA (6.6 mg of ceftiofur equivalents/kg, s.c.) was administered into the posterior aspect of a pinna. A second group of calves received a single dose of vehicle (0.03 mL/kg, s.c.; controls). Corneal ulcers were photographed, and clinical signs were assessed in calves every 3 to 4 days for 21 days. RESULTS: A positive treatment effect was detected at SFS. Results at the CD were inconclusive because ulcer healing occurred rapidly in control and CCFA-treated calves. At SFS, treatment with CCFA resulted in shorter mean healing times, smaller corneal ulcer surface area measurements, amelioration of ocular discharge and photophobia, and a 50% increase in the percentage of calves healed by day 14. After adjustment for initial corneal ulcer size, treatment with CCFA resulted in a 4-fold increase in the odds of corneal ulcer healing by day 14, compared with controls. CONCLUSIONS AND CLINICAL RELEVANCE: A single dose of CCFA administered into the posterior aspect of a pinna had a positive treatment effect against naturally occurring IBK in calves with corneal ulcerations. 相似文献
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Quantum computation as geometry 总被引:1,自引:0,他引:1
Quantum computers hold great promise for solving interesting computational problems, but it remains a challenge to find efficient quantum circuits that can perform these complicated tasks. Here we show that finding optimal quantum circuits is essentially equivalent to finding the shortest path between two points in a certain curved geometry. By recasting the problem of finding quantum circuits as a geometric problem, we open up the possibility of using the mathematical techniques of Riemannian geometry to suggest new quantum algorithms or to prove limitations on the power of quantum computers. 相似文献
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Naylor JM Poirier KL Hamilton DL Dowling PM 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2006,20(6):1408-1413
The effect of changes in feed intake on auscultatable gastrointestinal sounds has not been systematically studied. Disagreement also is present in the literature about variation in sounds according to the quadrant of auscultation. Gastrointestinal sounds were recorded over the center of the left dorsal, left ventral, right ventral, and right dorsal quadrants and over the middle of the right abdominal flank. During 24 hours (n = 4) or 48 hours (n = 5) of fasting, there was a reduction in the intensity of gastrointestinal sounds as assessed by analysis of sound recordings. There was also a reduction in the number of mixing-like and propulsive-like sounds heard by 2 blinded observers. After refeeding, there was a marked increase in sound. Sound intensity varied among abdominal quadrants, but blinded observers did not notice significant differences in the number of mixing-like sounds. The left dorsal quadrant was quieter than others during fasting and refeeding. The right ventral quadrant appeared to be least affected by fasting, and sounds were louder over the right ventral and right middle quadrants than over the others. The blinded observers' perceptions of sound correlated poorly with one another and with objective measures of sound intensity. This experiment demonstrates the effectiveness of computerized analysis of abdominal sound in detecting a reduction in the intensity of gastrointestinal sounds during fasting and their return during refeeding. The left dorsal quadrant was quieter than other quadrants, likely because of its position over the small colon. There was considerable observer variation in the number of intestinal sounds heard. 相似文献
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Sjöblom T Jones S Wood LD Parsons DW Lin J Barber TD Mandelker D Leary RJ Ptak J Silliman N Szabo S Buckhaults P Farrell C Meeh P Markowitz SD Willis J Dawson D Willson JK Gazdar AF Hartigan J Wu L Liu C Parmigiani G Park BH Bachman KE Papadopoulos N Vogelstein B Kinzler KW Velculescu VE 《Science (New York, N.Y.)》2006,314(5797):268-274
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BACKGROUND: Standard procedures for evaluation of pesticide performance do not take into account pest behavioral response or incomplete spray coverage. In this study, a series of laboratory experiments was conducted with two non‐systemic miticides (propargite and hexythiazox) applied to cotyledon cotton plants, which were subsequently infested with spider mites. The results of these laboratory experiments are discussed through a comprehensive pest population dynamics model. RESULTS: When cotton leaves were submerged in miticide solutions, both miticides provided effective control of spider mites. In a two‐choice test it was demonstrated that propargite was repellent to spider mites, but not hexythiazox. Finally, the spray coverage on cotton plants was varied, and, for both miticides, significantly positive relationships between spray coverage and spider mite mortality were shown. However, propargite required higher spray coverage (20%) than hexythiazox (10%) to control spider mites. A theoretical model showed that, without repellency, the pesticide performance is positively correlated with target pest mobility. If the pesticide is repellent, the probability of exposure decreases, especially for a less mobile pest. CONCLUSION: With an experimental and theoretical modeling approach, it was demonstrated how the combination of behavioral avoidance and low spray coverage can markedly reduce pesticide performance. Copyright © 2012 Society of Chemical Industry 相似文献
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Sonnenberg GF Monticelli LA Alenghat T Fung TC Hutnick NA Kunisawa J Shibata N Grunberg S Sinha R Zahm AM Tardif MR Sathaliyawala T Kubota M Farber DL Collman RG Shaked A Fouser LA Weiner DB Tessier PA Friedman JR Kiyono H Bushman FD Chang KM Artis D 《Science (New York, N.Y.)》2012,336(6086):1321-1325
The mammalian intestinal tract is colonized by trillions of beneficial commensal bacteria that are anatomically restricted to specific niches. However, the mechanisms that regulate anatomical containment remain unclear. Here, we show that interleukin-22 (IL-22)-producing innate lymphoid cells (ILCs) are present in intestinal tissues of healthy mammals. Depletion of ILCs resulted in peripheral dissemination of commensal bacteria and systemic inflammation, which was prevented by administration of IL-22. Disseminating bacteria were identified as Alcaligenes species originating from host lymphoid tissues. Alcaligenes was sufficient to promote systemic inflammation after ILC depletion in mice, and Alcaligenes-specific systemic immune responses were associated with Crohn's disease and progressive hepatitis C virus infection in patients. Collectively, these data indicate that ILCs regulate selective containment of lymphoid-resident bacteria to prevent systemic inflammation associated with chronic diseases. 相似文献