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排序方式: 共有260条查询结果,搜索用时 156 毫秒
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Comparison of diagnostic accuracy of laparoscopic 3 mm and 5 mm cup biopsies to wedge biopsies of canine livers 下载免费PDF全文
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农业网站评价方法与评价指标体系研究 总被引:2,自引:0,他引:2
互联网技术的迅速发展推动了科技的进步与信息的迅速传播,农业网站利用现代技术服务"三农"、推动产业升级,是现代农业发展的重要体现和重要标志。通过对当前农业网站建设情况的分析,结合农业行业特点,总结了开展农业网站评价的方法与原则,提出了一套适合农业网站的评价指标体系,为农业网站建设提供参考。 相似文献
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Robert C Cole Federica Morandi James Avenell Gregory B Daniel 《Veterinary radiology & ultrasound》2005,46(2):146-152
The purpose of this study was to (1) establish a technique for ultrasound-guided trans-splenic portal scintigraphy (TSPS) using 99mTcO4(-), (2) evaluate portal vein morphology, (3) compare the radiation exposures for TSPS vs. per-rectal portal scintigraphy (PRPS), and (4) compare the quality of numerical data from the TSPS vs. PRPS. Eight juvenile dogs underwent PRPS and TSPS (minimum of 48h between studies) after initial screening tests. PRPS was done according to established protocol using 425 +/- 36MBq (mean +/- SD) of 99mTcO4(-). TSPS was done with the dogs in right lateral recumbency over the gamma camera. 99mTcO4(-) (57 +/- 13.9 MBq) was injected into the spleen 1-2s following initiation of the dynamic acquisition. The frame rate was 4 frames/s for 5 min. There was significantly lower radioactivity of 99mTcO4(-) given and significantly higher total counts recorded in the liver and heart during the TSPS compared with PRPS. The total counts for the TSPS and PRPS were 7120 +/- 4386 and 830 +/- 523, respectively. Percent absorption from the spleen was 52.5 +/- 19.1% compared with 9.2 +/- 5.7% for the colon. Calculated transit time for the TSPS studies was 7 +/- 2.3s. In TSPS studies, the splenic and portal veins were clearly identified. Radiation exposure levels of the dogs were significantly lower following TSPS than after PRPS. TSPS appears superior to PRPS as a method to image the portal venous system representing a valid alternative diagnostic test for animals with suspected portosystemic shunts. 相似文献
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ROBERT H. WRIGLEY BVSc MS DVR MRCVS RICHARD D. PARK DVM PHD LINDA J. KONDE DVM JACK L. LEBEL DVM PHD 《Veterinary radiology & ultrasound》1987,28(6):208-212
Photographic subtraction was made of 38 canine portal venograms to remove the images of the overlying abdominal structures and enhance the radiographic contrast of portal veins. The improved visual quality of the subtracted portogram aided in the detection of portosystemic shunts and intrahepatic portal veins. The subtraction studies revealed portosystemic shunts not detected on the initial portal venogram. 相似文献
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AIM:This study was conducted to evaluate the effects of postoperative immune-enhancing parenteral nutrition on the nutritional statue,immune function,and inflammatory responses in patients undergoing portal hypertension surgery. METHODS: This study was designed as a prospective,randomized and controlled clinical trial. Forty-two patients undergoing portal hypertension surgery were randomly assigned to receive either an immune-enhancing parenteral nutrition(adding glutamine and recombinant human growth hormone,n=22) or an isocaloric and isonitrogenous control standard parenteral nutrition(n=20) for seven days. Parenteral nutrition was initiated 3 days after surgery. Blood samples were obtained on day 0,3,and 10. Host nutritional statue was evaluated by measuring levels of prealbumin and transferrin,immunity was observed by measuring levels of CD4+ cells,CD8+ cells,CD4+/CD8+,IgG,IgM and IgA,and the inflammatory responses was determined by assessing IL-2,TNF-α and C-reactive protein(CRP) levels. RESULTS:On postoperative day 10,among patients receiving an immune-enhancing parenteral nutrition,prealbumin,transferrin,CD4+ cells,CD4+/CD8+,IgG and IL-2 levels were significantly higher than those in control group,and TNF-α and CRP concentrations were significantly decreased(P<0.05). CONCLUSION:Postoperative administration of immune-enhancing parenteral nutrition in patients undergoing portal hypertension surgery can improve postoperative nutritional statue and immune function,and relieve inflammatory response. 相似文献
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Fintan J. McEvoy MVB PhD Myra A. Forster-van Hijfte DVM Robert N. White BSc BVetMed 《Veterinary radiology & ultrasound》1998,39(3):234-237
This study reports data obtained from per-rectal 99m Tc-pertechnetate portal scintigraphy in normal cats. It examines the effects of chemical restraint and the methods employed in defining regions of interest (ROIs) on the shunt index derived from this data. Six normal cats were used for the study; all six were chemically restrained for imaging using propofol and later four of them were manually restrained for comparison. Portal blood flow was studied and the mean shunt index was found to be 5.9%± 3.9 when ROIs were operator defined and 9.2%± 4.4 when ROIs were defined using an isocontour program. In cats that were restrained using propofol and operator defined ROIs, the mean value for the time between detection of radioactivity in the liver and in the heart was 14 ± 1 seconds. 相似文献
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以改进的D&M信息系统成功模型为理论支撑,提出了建立公众对政府门户网站持续信任的机制模型。以北京政府门户网站———首都之窗为研究对象,实证分析的结果表明公众对政府的信任和信息质量显著影响公众对政府门户网站的持续信任。系统质量和服务质量对公众对政府门户网站的满意具有积极作用。公众对政府门户网站的满意和信任显著影响公众使用政府门户网站的意愿。 相似文献
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网站建设与公共图书馆的延伸服务 总被引:1,自引:0,他引:1
对公共图书馆网站建设进行了简要论述,阐明加强网站建设可以使公共图书馆延伸服务。 相似文献
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随着高校教育信息化步伐的逐步推进,专题学习网站的建设成为广大教育工作者探究的新热点,本文基于分析专题学习网站特性上.结合网站开发的实用技术,探讨如何开发高质量的专题学习网站. 相似文献