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61.
An evaluation of fresh gas flow rates for spontaneously breathing cats and small dogs on the Humphrey ADE semi‐closed breathing system 下载免费PDF全文
ObjectiveTo evaluate the fresh gas flow (FGF) rate requirements for the Humphrey ADE semi-closed breathing system in the Mapleson A mode; to determine the FGF at which rebreathing occurs, and compare the efficiency of this system to the Bain (Mapleson D) system in spontaneously breathing cats and small dogs.Study DesignProspective clinical study.AnimalsTwenty-five healthy (ASA score I or II) client-owned cats and dogs (mean ± SD age 4.7 ± 5.0 years, and body weight 5.64 ± 3.26 kg) undergoing elective surgery or minor procedures.MethodsAnaesthesia was maintained with isoflurane delivered via the Humphrey ADE system in the A mode using an oxygen FGF of 100 mL kg−1 minute−1. The FGF was then reduced incrementally by 5–10 mL kg−1minute−1 at approximately five-minute intervals, until rebreathing (inspired CO2 >5 mmHg (0.7 kPa)) was observed, after which flow rates were increased. In six animals, once the minimum FGF at which rebreathing occurred was found, the breathing system was changed to the Bain, and the effects of this FGF delivery examined, before FGF was increased.ResultsRebreathing did not occur at the FGF recommended by the manufacturer for the ADE. The mean ± SD FGF that resulted in rebreathing was 60 ± 20 mL kg−1minute−1. The mean minimum FGF at which rebreathing did not occur with the ADE was 87 ± 39 mL kg−1minute−1. This FGF resulted in significant rebreathing (inspired CO2 8.8 ± 2.6 mmHg (1.2 ± 0.3 kPa)) on the Bain system.ConclusionsThe FGF rates recommended for the Humphrey ADE are adequate to prevent rebreathing in spontaneously breathing cats and dogs <15 kg.Clinical relevanceThe Humphrey ADE system used in the A mode is a more efficient alternative to the Bain system, for maintenance of gaseous anaesthesia in spontaneously breathing cats and small dogs. 相似文献
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BMGK-1型微计算机木材干燥监控系统的研制 总被引:1,自引:1,他引:1
本文就微计算机技术在木材干燥生产过程控制中的应用,作了理论和技术方面的分析。同时对研制成功的BMGK-1型微计算机木材于燥监控系统的软硬件结构、原理及技术经济性能进行了全面的论述。 本系统能与我国现有各类木材干燥设备配套使用,并可以提高生产效率、保证干燥质量、减轻工人劳动强度,节约能源效果显著。工业试验表明:与人工控制相比,平均节约工时10%以上。 相似文献
63.
Effects of dissolved carbon dioxide on the integrity of the rumen epithelium: An agent in the development of ruminal acidosis 下载免费PDF全文
The carbon dioxide released and dissolved in rumen fluid may easily permeate across the epithelial cell membrane. Thus, we hypothesized that CO2 may act as proton carrier and induce epithelial damage under acidotic conditions. Ovine ruminal epithelia were mounted in Ussing chambers under short‐circuit conditions. The serosal buffer solution had a constant pH of 7.4 and was gassed either with 100% oxygen or with carbogen (95% O2/5% CO2). The mucosal solution was gassed with either 100% oxygen or 100% carbon dioxide. The mucosal pH was lowered stepwise from 6.6 to 5.0 in the presence or absence of short‐chain fatty acids (SCFA). The transepithelial conductance (Gt) as an indicator of epithelial integrity and the short‐circuit current (Isc) as an indicator of active electrogenic ion transfer were continuously monitored. At an initial mucosal pH of 6.6, there was no significant difference in Gt between the treatment groups. In the absence of both SCFA and CO2, Gt remained constant when the mucosal solution was acidified to pH 5.0. In the presence of SCFA, mucosal acidification induced a significant rise in Gt when the solutions were gassed with oxygen. A small increase in Gt was observed in the mucosal presence of CO2. However, no difference in final Gt was observed between SCFA‐containing and SCFA‐free conditions under carbon dioxide gassing during stepwise mucosal acidification. The SCFA+proton‐induced increase in Gt could also be minimized by serosal gassing with carbogen. Because of the SCFA+proton‐induced changes in Gt and their attenuation by CO2, a protective role for mucosally available carbon dioxide may be assumed. We suggest that this effect may be due to the intraepithelial conversion of carbon dioxide to bicarbonate. However, the serosal presence of CO2 at a physiological concentration may be sufficient to protect the epithelia from SCFA+proton‐induced damage for a certain period of time. 相似文献
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通过对喷油驱动电路的波形测试来介绍波形分析的一般方法,并通过故障诊断实例来反映波形分析法诊断汽车故障的优越性。 相似文献
67.
针对高职院校在汽车专业、汽车电器课程教学过程中,对电器系统部件工作原理与电路检修实践技能的掌握理解困难等诸多因素不能较好地解决教、学与研究的矛盾,本文以汽车启动系电路为例,就汽车电器仿真教学软硬件进行了开发研究与探讨。 相似文献
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介绍了液力缓速器的结构和工作原理,以某款商用车匹配采埃孚液力缓速器为例,详细阐述了商用车匹配缓速器时的空间布置、控制策略、冷却回路等设计内容.通过实车转鼓试验研究缓速器的制动性能.结果表明:整车匹配液力缓速器时,适当增大整车散热功率,能保证液力缓速器稳定的持续制动性能. 相似文献