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831.
李翔 《农业图书情报学刊》2012,(3):192-195
阐述了地方文献服务的内涵,并从服务对象、服务内容、服务模式、服务馆员、服务承诺、服务评估6个方面探讨了图书馆地方文献服务的具体细节和管理责任。 相似文献
832.
对新引进IR不育系的观察与评价 总被引:8,自引:1,他引:7
从印度引进15个IRRI育成的不育系和相应的保持系,在中国水稻研究所试验基地(富阳)观测其育性及主要农艺性状,并初步配组测产。结果表明,10个不育系育性稳定,符合标准;IR58025A与明恢63、T9010配组,其杂种产量与汕优63相仿,但生育期较短、米质较优。 相似文献
833.
通过对检疫性有害生物的发生危害情况进行综合分析研究,揭示了一套检疫性病、虫、杂草的发生面积统计标准以及发生程度4级评估方法,并利用该方法制作了2000~2002年广西23种检疫性有害生物疫情发生情况图. 相似文献
834.
Toshihiro NADE Kazuhisa FUJITA Masashi FUJII Masaya YOSHIDA Teikichi HARYU Satsuki MISUMI Toshiaki OKUMURA 《Animal Science Journal》2005,76(5):513-517
An X‐ray computed tomography (CT) system for live standing cattle was developed for studying the meat yield, carcass composition and so on. The gantry contained three X‐ray tubes and detectors that corresponded to each X‐ray tube. The system was able to operate while the animal remained standing. The scan area had a diameter of 900 mm. The Musculus longissimus and Musculus trapezius areas, and the back fat thickness in the CT image were evaluated and compared to the actual cross‐section of the carcass using eight cattle. The differences among the muscles, and the subcutaneous and intermuscular fat were easily recognized. The correlation coefficient between the CT image and the actual carcass photograph of the M. longissimus area and the back fat thickness was high (r = 0.84, r = 0.93, P < 0.01). The present study demonstrated that muscle, fat and bone can be clearly imaged from a live standing animal using X‐ray equipment. 相似文献
835.
干旱区土地退化生态系统的评价方法 总被引:12,自引:2,他引:12
本文简要介绍了我国干旱区的二种分类方法、分布面积和自然特点。干旱区土地生态系统退化的主要类型有草场退化,而养耕地退化和灌溉地退化,国内外各种退化类型的分布面积。提出退化土地生态系统评价原则,主要退化土地的评价指标体系,评价因子权重的确定方法,综合评价方法及地理信息系统的应用。 相似文献
836.
837.
C.K.K. Gachene 《Soil Use and Management》1995,11(1):1-4
Abstract. The erosion susceptibility of the Erosion Research Farm at Kabete Campus was mapped using a qualitative parametric method. A grid soil survey of the 4 ha farm was combined with a map of slope gradients, slope segments being delineated by breaks in slope. Rainfall erosivity and soil erodibility were also measured. Areas with the greatest erosion susceptibility according to this method were those occupying convex slope positions and slopes of more than 30%. Field observations and soil loss measurements generally supported the erosion susceptibility rating map produced by this method. The soil and erosion susceptibility maps were useful for planning erosion control measures and for selecting suitable sites for runoff plot experiments. 相似文献
838.
农村产业结构的评价与分析 总被引:2,自引:0,他引:2
根据农村产业结构调整的目标和评价指标,对河南省农村产业结构进行了评价和分析。结果表明,农村产业结构经过10a的调整,发生了质的变化,但是,农村劳力转移速度和农民收入增长速度远滞后于农村产业结构调整的速度。作者针对存在问题,提出了进一步调整的建议。 相似文献
839.
DENG Hua LI Hui YANG Hong ZHOU Zhaohai LIANG Haozhao XU Zhigao WU Fuda LI Qiaofeng HUANG Luqi 《畜牧兽医学报》1956,51(11):2836-2848
To study the clinicopathology and histopathology of African swine fever (ASF), and to explore the internal relationship between pathological changes and disease occurrence and development and its pathological mechanism, 13 Landrace pigs with bodyweight about 20 kg were intramuscular injected with African swine fever virus (ASFV), strain Pig/HLJ/18 at a dose of 102HAD50·mL-1. During the experiment, all the dead pigs were systematically dissected and sampled, paraffin sections were produced, and haematoxylin-eosin staining was performed. Clinicopathological evaluation standards for acute ASF were established, then pathological lesions (classification variables) were expressed by counting frequency and percentage, and the lesion degree (continuous variables) was graded and scored according to different pathological changes of various tissues and organs. The results showed that all infected pigs were in line with the clinical characteristics of ASF, including acute, febrile and highly infectious, with a 100% incidence rate and 100% mortality. The dead pigs showed typical characteristics of septicemia, cadavers prone to corruption, blood clotting adverse or hemolysis, rigor mortis incomplete. The main pathological lesions were hemorrhagic necrotizing lymphadenitis, acute inflammatory splenomegaly (septic spleen), cerebral edema, pulmonary edema and lung consolidation et al. The spleen and lymphonodus are the target organs attacked by ASFV, with the most significant lesions, the earliest occurrence time, the longest duration and the highest frequency. The most prominent pathological changes are blood circulation disorders, including multiple pathological manifestations such as edema, hyperemia, congestion, hemorrhage, infarction, disseminated intravascular coagulation (DIC), and the most important characteristics are hemorrhagic lesions. The inflammatory reaction of lymphocytic exudation caused by ASFV runs through the whole process, especially in the middle and later stages of the course. The results suggest that the main pathological process of acute African swine fever is a typical immune/inflammatory cascade reaction and severe systemic blood circulation disorder, which resulted in the high incidence rate and high mortality rate of acute ASF. 相似文献
840.
提高农业科技查新工作质量的探讨 总被引:2,自引:2,他引:0
李国成 《农业图书情报学刊》2003,(5):117-121
本文针对当前农业科研查新检索的现状,结合自身的工作实际,阐述了农业科技查新工作的重要作用。论述了农业科研成果的特点,着重对农业查新的业务受理、文献资源建设、检索策略制定、“零”结果的判断、文献相关性分析、查新报告结论和工作人员素质等环节,探讨如何提高农业科技查新工作质量的措施。 相似文献