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991.
OBJECTIVE: To evaluate the suitability of a 'mini parallel Lack' (MPL) breathing system for use in spontaneously breathing cats and to compare the fresh gas flow requirement with that of a modified Ayre's T-piece (MATP). ANIMALS: Twenty client-owned cats, ASA I and II, presented for elective procedures requiring anaesthesia. MATERIALS AND METHODS: Pre-anaesthetic medication and induction of anaesthesia were carried out using several techniques commonly used in our teaching hospital. Anaesthesia was maintained with halothane or isoflurane vaporized in either oxygen or with a mixture of oxygen and nitrous oxide. Both breathing systems were evaluated in each cat, with the order of use randomized. Initial fresh gas flows were 300 mL kg(-1) minute(-1) for the MPL and 500 mL kg(- 1) minute(-1) for the MATP. After a 20-minute stabilization period, fresh gas flow was reduced by 200 mL minute(-1) every 5 minutes until re-breathing--defined as an increase in the inspired partial pressure of carbon dioxide to 0.3 kPa (2 mm Hg)--was detected. The fresh gas flow was then increased in 100 mL minute(-1) increments until re-breathing was no longer detectable, and this value was recorded as the minimum fresh gas flow requirement for the breathing system in use. The procedure was then repeated for the second breathing system. Minimum fresh gas flow requirements were compared using a paired Students t-test. Cardiopulmonary variables were compared using anova. Valve opening pressure was measured in the MPL using a manometer. RESULTS: The mean (+/-SD) fresh gas flow that prevented re-breathing with the MPL (510 +/- 170 mL minute(-1); equivalent to 142 +/- 47 mL kg(-1) minute(-1)) was significantly lower than that required for the MATP (1430 +/- 560 mL minute(-1); equivalent to 397 +/-155 mL kg(-1) minute(-1)). There were no significant differences in cardiopulmonary variables attributable to the use of the two breathing systems. The MPL valve opening pressure was 1.1 cm H2O. CONCLUSIONS: The MPL breathing system used lower gas flows than the MATP without affecting cardiovascular or respiratory function. Clinical relevance In spontaneously breathing cats, the MPL offers the advantages of a reduction in cost and atmospheric pollution because less volatile agent is vaporized. 相似文献
992.
In a 4 x 4 Latin square design study, four rumen-cannulated local yellow cattle, average weight 330 kg, were fed urea-treated fresh rice straw (UFRS) ad libitum and given 1 kg cassava root meal daily as basal diet in each 30-day trial period. Four treatment levels of crude protein of fresh cassava tops (FCT) were supplied: 0 (FCT0), 50 (FCT50), 100 (FCT100) and 150 g (FCT150) crude protein per 100 kg body weight. The results showed a continuous decrease in dry matter intake (DMI) of UFRS with increasing level of FCT supplementation (p<0.001). Total DMI for treatments FCT150, FCT100, FCT50 and FCT0 were 2.66, 2.42, 2.23 and 2.05 kg dry matter per 100 kg live weight per day, respectively. Increasing levels of FCT supplementation increased the concentration of total volatile fatty acids (p<0.05) and ammonia (p<0.001) and resulted in a decrease in pH (p<0.05). Rumen protozoa population varied widely but was significantly lower with increasing FCT supplementation (p<0.001), while rumen bacteria population was higher (p<0.05). Overall, average plasma triiodothyronine and thyroxine concentrations in the four groups were respectively 1.36, 0.94, 0.91, 0.80 ng/ml (p<0.01) and 60.9, 48.7, 45.2, 42.5 ng/ml (p<0.001). There were non-significant differences in alanine aminotransferase and aspartate aminotransferase concentrations among the treatments. 相似文献
993.
为探明海南南繁生态区玉米自交系雄穗发育动态,以6个不同类型玉米自交系KWS2-4321、13H6、10H9、KWS2-2220、11H37、PHHJC为试验材料,研究了玉米自交系雄穗鲜重、雄穗体积发育动态,雄穗逐日开花与逐时开花规律及雄穗逐日散粉特点。结果表明:雄穗鲜重发育呈现先上升后下降趋势,雄穗发育第1~4 d鲜重变化不大,第7~10天鲜重迅速增加,第13~16天稍有下降,玉米自交系雄穗鲜重与发育日数间经拟合附合二次多项式数量关系;雄穗体积与雄穗鲜重变化趋势不同,随雄穗发育进程的推进呈先升高后下降,最后又升高的变化趋势;雄穗开花可持续6~8 d,第2~4 d为盛花期,超过开花总量50%,第1 d开花较少,第2~4天开花数急剧增加,第7~8天开花数显著降低;07∶00、08∶00雄穗开花数量较少,09∶00、10∶00雄穗开花数量迅速增加,其开花数超过当日总开花数40%,11∶00开花数有所下降,12∶00之后开花数显著减少;逐日散粉量随散粉日数的推进呈现先升高后下降趋势,散粉后2~4 d达最大峰值,散粉持续5~8 d,与逐日开花规律基本一致。雄穗鲜重第7~10天增加快,雄穗体积与雄... 相似文献
994.
In order to improve somatic embryogenesis production in date palm Phoenix dactilyfera L. cv. Deglet Nour (DN), a comparative study between somatic (SE) and zygotic (ZE) embryos developments was carried out. The data showed that ZE maturation occurred from 10 to 19 weeks after pollination (WAP). During this period, the fresh weight (FW) and the dry weight (DW) of ZE increased progressively to reach a maximum level at 19 WAP. SE development occurred in three distinct stages. The DW remained constant during the two first stages, and declined slightly during the third and final stage. Embryo protein analysis revealed significant differences between ZE and SE. The ZE total protein level was initially low and increased to the maximum at mature stage. However, no significant change in total protein was detected during SE development. SDS-PAGE analysis showed a poor protein profile for SE, compared to that of ZE. In the latter, a 22 kDa protein was identified by N-terminal sequencing as a glutelin. This protein was accumulated rapidly during early development and remained at a relatively constant level during ZE development, and then declined progressively 12 days after embryo germination (DG). This protein seems to be absent in SE. 相似文献
995.
996.
997.
Husni H. Mohd Rafdi Daryl C. Joyce Donald E. Irving Subhendu S. Gantait 《The Journal of Horticultural Science and Biotechnology》2018,93(1):73-80
The short vase life of Acacia holosericea cut stems needs to be improved before they are marketable as cut foliage for floral arrangement. The effects of citric acid, Cu2+ and sucrose were investigated for their efficacy in postharvest treatments to extend vase life of the cut stems. Five experiments were conducted involved combinations of citric acid either with Cu2+ or sucrose. Vase life, relative fresh weight (RFW), and vase solution uptake were measured as indicators of cut stem quality. The effect of Cu2+ alone was shown to be consistently superior in improving vase life by up to 1.9-fold as compared with deionised water control. Citric acid had a smaller effect than Cu2+ and did not act synergistically with Cu2+. Sucrose on its own or in combination with citric acid did not improve vase life significantly; instead sucrose promoted early wilting or desiccation of the cut foliage. 相似文献
998.
999.
[目的]解决卷烟生产过程中制丝线损耗高、出丝率低的问题.[方法]对大理卷烟厂新投产的制丝线进行损耗测试,找到损耗高的工序并探寻原因,同时对损耗高的工序进行改进,以提高烟丝出丝率.[结果]针对加湿滚筒易粘附烟丝的问题,将滚筒自动水洗方式改为在滚筒内安装喷吹装置进行清洗,滚筒清洗废料由90 kg减少为50 kg;对夜班清扫废料进行分类整理回收,每天可回收15 kg的烟叶;将切丝前分料器下料口角度由30°扩宽为60°,使切丝除尘的造碎率由0.51%降低至0.29%.改进后,该制丝线出丝率由97.65%提高至98.17%.[结论]经改进后的新制丝线节约了烟叶原料,有效降低了烟叶消耗,提高了资源利用率和企业经济效益. 相似文献
1000.