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101.
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F.J. TENDILLO DVM PhD Diplomate ECVA A. MASCÍAS DVM M. SANTOS DVM J. LÓPEZ-SANROMÁN DVM PhD R. De ROSSI DVM F. SAN ROMÁN DVM PhD LA. GÓMEZ de SEGURA DVM PhD 《Veterinary surgery : VS》1997,26(4):354-357
Objective — To determine the minimum alveolar concentration (MAC) of desflurane (DES) in the horse.
Study Design — Prospective study.
Animals — Six healthy adult horses (three males and three females) weighing 370 ±16 kg and aged 9 ±2 years old.
Methods — Anesthesia was induced with DES vaporized in oxygen via a face mask connected to a large-animal, semiclosed anesthetic circle system. The horses were endotracheally intubated and positioned in right lateral recumbency. Inspired and end-tidal DES were monitored using a calibrated Ohmeda RGM 5250 multigas analyzer (Ohmeda-BOC, Spain). The MAC of desflurane that prevented gross purposeful movement in response to 60 seconds of noxious electrical stimulation of oral mucous membranes was determined.
Results — The time from the start of DES administration to lateral recumbency was 6.1 ±0.9 min. The MAC of DES in these horses was 7.6 ±0.4%. Time required for the animal to regain sternal recumbency after 98 ±4 minutes of anesthesia was 6.6 ±0.5 minutes and the time to standing was 14.3 ±2.7 minutes.
Conclusions — The MAC of desflurane in these horses was 7.6 ±0.4%. DES provided a rapid induction to, and recovery from, anesthesia.
Clinical Relevance — Desflurane offers the potential for more precise control during anesthesia, and may allow a faster and uneventful recovery. It is important to know the MAC of an inhalant to use it clinically. 相似文献
Study Design — Prospective study.
Animals — Six healthy adult horses (three males and three females) weighing 370 ±16 kg and aged 9 ±2 years old.
Methods — Anesthesia was induced with DES vaporized in oxygen via a face mask connected to a large-animal, semiclosed anesthetic circle system. The horses were endotracheally intubated and positioned in right lateral recumbency. Inspired and end-tidal DES were monitored using a calibrated Ohmeda RGM 5250 multigas analyzer (Ohmeda-BOC, Spain). The MAC of desflurane that prevented gross purposeful movement in response to 60 seconds of noxious electrical stimulation of oral mucous membranes was determined.
Results — The time from the start of DES administration to lateral recumbency was 6.1 ±0.9 min. The MAC of DES in these horses was 7.6 ±0.4%. Time required for the animal to regain sternal recumbency after 98 ±4 minutes of anesthesia was 6.6 ±0.5 minutes and the time to standing was 14.3 ±2.7 minutes.
Conclusions — The MAC of desflurane in these horses was 7.6 ±0.4%. DES provided a rapid induction to, and recovery from, anesthesia.
Clinical Relevance — Desflurane offers the potential for more precise control during anesthesia, and may allow a faster and uneventful recovery. It is important to know the MAC of an inhalant to use it clinically. 相似文献
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R. ROMERO-PEREZGROVAS N. VERHULST D. DE LA ROSA V. HERNÁNDEZ M. MAERTENS J. DECKERS B. GOVAERTS 《土壤圈》2014,24(4):476-486
In the subtropical highlands of Central Mexico, where the main crop is maize (Zea mays), the conventional practice (CP) involves tillage, monoculture and residue removal, leading to soil degradation and unsustainable use of natural resources and agricultural inputs. Conservation agriculture (CA) has been proposed as a viable alternative in the region, based on reduction in tillage, retention of adequate levels of crop residues and soil surface cover and use of crop rotation. This study began in 2009 when the highlands of Central Mexico suffered from a prolonged drought during vegetative maize growth in July-August, providing an opportunity for the on-farm comparison of CA with CP under severe drought conditions which 21 climate change models projected to become more frequent. Under dry conditions, CA resulted in higher yields and net returns per hectare as early as the first and second years after adoption by farmers. As an average of 27 plots under farmers' management in 2009, the maize yields were 26% higher under CA (6.3 t ha-1) than under CP (5.0 t ha-l). 2010 was close to a normal year in terms of rainfall so yields were higher than in 2009 for both practices; in addition, the yield difference between the practices was reduced to 19% (6.8 t ha-1 for CA vs. 5.7 t ha-1 for CP). When all the 2009 and 2010 observations were analyzed in a modified stability analysis, CA had an overall positive effect of 3 838 Mexican Pesos ha-1 (320 $US ha-1) on net return and 1.3 t ha-1 on yield. After only one to two years of adoption by farmers on their fields, CA had higher yields and net returns under dry conditions that were even drier than those predicted by the analyzed 21 climate change models under a climate change scenario, emission scenario A2. 相似文献
107.
McCorkle R Angilello J Coleman G Feder R LA Placa SJ 《Science (New York, N.Y.)》1979,205(4404):401-402
Soft x-ray contact microscopy, utilizing single-shot exposures of approximately 60 nanoseconds duration in polymethyl methacrylate, has been realized with a resolution of 300 angstroms. The radiation spectrum is intense in the "window" between 23 and 44 angstroms where water is transparent compared to biological materials, and therefore permits viewing of wet samples. 相似文献
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D Aberdein JS Munday KE Dittmer RW Heathcott LA Lyons 《New Zealand veterinary journal》2013,61(6):327-331
Abstract
AIMS
To determine the frequency of the FAS-ligand gene (FASLG) variant associated with feline autoimmune lymphoproliferative syndrome (FALPS) and the proportion of carriers of the variant in three British shorthair (BSH) breeding catteries in New Zealand. 相似文献110.
羌塘自然保护区湖泊变化及其原因分析 总被引:2,自引:0,他引:2
选取西藏羌塘自然保护区MSS、TM、ETM+数据和1[JP18]∶[JP]100 000地形图,以85° E为中心线,将研究区划分为东西两部分,解译该区域面积大于1 km2的所有湖泊。结果表明:1975-1990年,羌塘自然保护区湖泊呈退缩状态,湖泊个数由388个减少为277个,面积由6 603.3 km2减少到5 539.7 km2,面积减少达16.1%;2005年,湖泊个数比1990年增加164个,达441个,湖泊总面积9 652.2 km2,比1990年增加4 112.5 km2,增幅74.2%。在区域上,表现为东部变化幅度大于西部。同时,重点分析了研究区附近的狮泉河、改则、班戈、申扎、那曲、安多6个气象站1978-2007年的数据。结果显示:6个代表气象站年平均气温、年平均最高气温、年降水量均呈上升趋势,其中东部上升幅度较大,西部变化不明显;年蒸发量呈减少趋势。降水是影响湖泊变化最主要的因素。 相似文献