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冬季日光温室的保温措施及对天气性灾害的预防对策 总被引:1,自引:0,他引:1
高效节能日光温室以太阳能为主要能源 ,不加温或临时加温就能进行果菜类生产 ,但近几年发展的温室偏高偏宽 ,保温措施又跟不上 ,结果在1 999年冬至 2 0 0 0年春雪多、严寒的条件下 ,不少温室出现了 2℃以下低温 ,甚至冻害 ,使果菜类生产受到很大影响 ,造成了很大的损失。对此 ,我站经过试验和调研 ,提出如下的保温措施及对天气灾害性的对策 ,使果菜类冬季能在日光温室得以正常生长 ,进一步提高冬季蔬菜生产的经济效益和社会效益 ,保证我市保护地蔬菜生产持续发展。1 温室结构与保温的关系沈阳市地处北纬 41°以北 ,冬至太阳高度角低 ,中午 … 相似文献
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自1960年来,已建造了数千幢部分或全部漏缝地板的肥育猪舍,但每头肥育猪的空间有限,通常为O.54~O.64平方米.在西欧进行的比较试验证明,当采用部分漏缝地板,且每头猪有o.70平方米空间时,技术效益较好.而如果猪能在箱型矮栏里休息,效果就更佳好动的肥育猪一般不怕贼风或低温的影响.试验表明,把饲喂和排粪区与躺卧区分开,是很有利的.躺卧区三面能够关闭,并可用顶盖覆盖,以创造 相似文献
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Jason B. King Jeryl C. Jones John H. Rossmeisl Jr Tisha A. Harper Otto I Lanz Stephen R. Werre 《Journal of veterinary science (Suw?n-si, Korea)》2009,10(3):225-232
Accurate pre-operative localization and removal of disc material are important for minimizing morbidity in dogs with thoracolumbar disc extrusions. Computed tomography (CT) is an established technique for localizing disc extrusions in dogs, however the effect of multi-planar reformatting (MPR) on surgeon diagnostic performance has not been previously described. The purpose of this study was to test the effect of MPR CT on surgeon diagnostic accuracy, certainty and agreement for localizing thoracolumbar disc extrusions in dogs. Two veterinary surgeons and one veterinary neurologist who were unaware of surgical findings independently reviewed randomized sets of two-dimensional (2D) and MPR CT images from 111 dogs with confirmed thoracolumbar disc extrusions. For each set of images, readers recorded their localizations for extruded disc material and their diagnostic certainty. For MPR images, readers also recorded views they considered most helpful. Diagnostic accuracy estimates, mean diagnostic certainty scores and inter-observer agreement were compared using surgery as the gold standard. Frequencies were compared for MPR views rated most helpful. Diagnostic accuracy estimates were significantly greater for MPR vs. 2D CT images in one reader. Mean diagnostic certainty scores were significantly greater for MPR images in two readers. The change in agreement between 2D and MPR images differed from zero for all analyses (site, side, number affected) among all three readers. Multi-planar views rated most helpful with the highest frequency were oblique transverse and curved dorsal planar MPR views. Findings from this study indicate that multi-planar CT can improve surgeon diagnostic performance for localizing canine thoracolumbar disc extrusions. 相似文献
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J. H. Rossmeisl Jr J. L. Robertson K. L. Zimmerman M. A. Higgins D. A. Geiger 《Veterinary and comparative oncology》2009,7(3):173-180
Meningiomas are the most common canine intracranial tumour. Neurologic disability and death from treatment failure remain problematic despite current surgical and radiotheraputic treatments for canine intracranial meningiomas. Cyclooxygenase-2 (COX-2) over-expression has been demonstrated in multiple canine malignancies, and COX-2 inhibitory treatment strategies have been shown to have both preventative and therapeutic effects in spontaneous and experimental models of cancer. The purpose of this study was to evaluate COX-2 expression in canine intracranial meningiomas. Immunohistochemical and Western blot (WB) analyses showed COX-2 expression in multiple tissues of the normal canine brain, and 87% (21/24) of intracranial meningiomas studied were immunoreactive to COX-2. No significant associations between COX-2 immunoreactivity and tumour grade were identified. Further studies are required to elucidate the physiologic roles of constitutive COX-2 expression in the central nervous system as well as its participation in meningioma tumourigenesis. 相似文献
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