全文获取类型
收费全文 | 299篇 |
免费 | 17篇 |
专业分类
林业 | 30篇 |
农学 | 54篇 |
基础科学 | 2篇 |
38篇 | |
综合类 | 15篇 |
农作物 | 31篇 |
水产渔业 | 4篇 |
畜牧兽医 | 110篇 |
园艺 | 6篇 |
植物保护 | 26篇 |
出版年
2021年 | 6篇 |
2020年 | 4篇 |
2018年 | 6篇 |
2017年 | 13篇 |
2016年 | 9篇 |
2015年 | 6篇 |
2014年 | 2篇 |
2013年 | 16篇 |
2012年 | 14篇 |
2011年 | 15篇 |
2010年 | 10篇 |
2009年 | 7篇 |
2008年 | 5篇 |
2007年 | 25篇 |
2006年 | 8篇 |
2005年 | 11篇 |
2004年 | 7篇 |
2003年 | 8篇 |
2002年 | 10篇 |
2001年 | 3篇 |
2000年 | 3篇 |
1999年 | 5篇 |
1998年 | 4篇 |
1997年 | 7篇 |
1996年 | 4篇 |
1995年 | 3篇 |
1994年 | 4篇 |
1993年 | 2篇 |
1992年 | 2篇 |
1991年 | 5篇 |
1990年 | 3篇 |
1989年 | 3篇 |
1988年 | 7篇 |
1987年 | 4篇 |
1986年 | 6篇 |
1985年 | 2篇 |
1984年 | 5篇 |
1981年 | 3篇 |
1980年 | 5篇 |
1979年 | 5篇 |
1978年 | 4篇 |
1977年 | 3篇 |
1976年 | 2篇 |
1975年 | 5篇 |
1973年 | 2篇 |
1971年 | 5篇 |
1970年 | 4篇 |
1969年 | 2篇 |
1967年 | 5篇 |
1966年 | 2篇 |
排序方式: 共有316条查询结果,搜索用时 15 毫秒
31.
32.
33.
Sharma R. N. Bhosale A. S. Joshi V. N. Hebbalkar D. S. Tungikar V. B. Gupta A. S. Patwardhan S. A. 《Phytoparasitica》1981,9(2):101-109
Phytoparasitica - The plantLavandula gibsonii (fam. Lamiaceae) has been found to possess various insectistatic activities against several insect pests. Acetone extracts of the whole plant exhibit... 相似文献
34.
R. P. Bansal R. C. Joshi B. Sharma U. Chandra 《Tropical animal health and production》1987,19(1):53-55
Reverse phase passive haemagglutination [RPHA] test was applied for the detection of rinderpest antigen in various organs of rinderpest infected cattle. The results of RPHA were compared with counter immunoelectrophoresis [CIE] and single radial haemolysis [SRH] test. RPHA was as sensitive as CIE and SRH in detecting rinderpest antigen. 相似文献
35.
S. V. Chanda A. K. Joshi P. P. Vaishnav Y. D. Singh 《Journal of Agronomy and Crop Science》1988,160(4):217-223
Fully expanded leaf occupying topmost position in a field grown pearl millet hybrid (BJ-104) and its parents (J-104 and 5141-A) were analysed at weekly intervals for chlorophylls, Hill activity and phosphoenolpyruvate carboxylase activity. Large ontogenic drifts in these parameters, made the actual comparison between hybrid and parents, difficult. However, up to 52 d the hybrid leaf possessed considerably higher chlorophyll pigments than its parents. Amongst the inbreds, the male parent was initially better than the female parent while at later stages, the trend was reversed. Hill activity and PEPcase were more in the male than in the female parent and the hybrid followed the better parent. Rate limiting steps for productivity, measured as NAR (g dry weight)−1 , were worked out in the female parent, using multiple regression and correlation analysis, and the significance of such an analysis is discussed in relation to plant productivity. 相似文献
36.
37.
The aim of the present study was to evaluate the merits of a coloured paste applied to cows as an aid to heat detection in a dairy herd. It was performed on 110 French Friesian cows under a loose housing system over one year. For comparison, the results of the previous year, with no paste application, were also computed. Results of heat detection by the herdsman and by paste removal were compared to expected ovulations assessed by regular rectal palpation and, or, plasma or milk progesterone patterns. The paste system improved the percentages of oestrus detection of post partum and post inseminated cyclic cows by 26 and 22 per cent respectively, compared to the previous year. Overall missed heat incidence was 15 per cent and over estimation was negligible (less than 5 per cent). The mean durability period of the paste in the absence of mounting was 13 days. This suggests that to achieve the above mentioned results, application of paste should be performed at least every two weeks when no previous heat has been recorded, or only once, two weeks after service to check for non-pregnancy. 相似文献
38.
39.
S. V. Chanda A. K. Joshi P. P. Vaishnav Y. D. Singh 《Journal of Agronomy and Crop Science》1988,160(2):125-131
Changes in the activities of enzymes of ammonia assimilation viz., glutamate dehydrogenase (GDH), glutamine synthetase (GS) and glutamate synthase (GOGAT), together with the activities of glutamate oxaloacetate transaminase (GOT) and glutamate pyruvate transaminase (GPT) were analysed in the topmost fully expanded leaf of pearl millet (Pennisetum americanum L. Leeke) hybrid BJ-104 , and its parents, J-104 and 5141-A , during the entire period of growth in field. Ammonia assimilation enzymes showed strong ontogenic trends and the hybrid attained activities either equal to the better (male) parent or showed better parental heterosis. In contrast to this both GOT and GPT activities were slightly higher than the poor (female) parent. The role of these enzymes in relation to chlorophyll synthesis and transport of metabolites from cellular compartments of C4 plants, are discussed. Surveying the literature on attempts to propose biochemical criteria for hybrid vigour, it is proposed that there cannot be a universal criterion, rather rate limiting steps in different cultivars should be searched. 相似文献
40.