全文获取类型
收费全文 | 321篇 |
免费 | 11篇 |
专业分类
林业 | 50篇 |
农学 | 6篇 |
34篇 | |
综合类 | 11篇 |
农作物 | 10篇 |
水产渔业 | 46篇 |
畜牧兽医 | 158篇 |
园艺 | 2篇 |
植物保护 | 15篇 |
出版年
2023年 | 1篇 |
2022年 | 6篇 |
2021年 | 16篇 |
2020年 | 6篇 |
2019年 | 2篇 |
2018年 | 4篇 |
2017年 | 10篇 |
2016年 | 8篇 |
2015年 | 14篇 |
2014年 | 10篇 |
2013年 | 22篇 |
2012年 | 24篇 |
2011年 | 26篇 |
2010年 | 7篇 |
2009年 | 6篇 |
2008年 | 29篇 |
2007年 | 32篇 |
2006年 | 15篇 |
2005年 | 25篇 |
2004年 | 17篇 |
2003年 | 12篇 |
2002年 | 8篇 |
2001年 | 10篇 |
2000年 | 5篇 |
1999年 | 1篇 |
1998年 | 2篇 |
1996年 | 3篇 |
1995年 | 2篇 |
1994年 | 1篇 |
1991年 | 2篇 |
1989年 | 2篇 |
1982年 | 1篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1978年 | 1篇 |
排序方式: 共有332条查询结果,搜索用时 48 毫秒
331.
The production of transparent exopolymer particles (TEP) by four diatoms, Coscinodiscus granii, Eucampia zodiacus, Rhizosolenia setigera, and Skeletonema sp., was examined. Most of the TEP in C. granii (74% of the maximum) were produced during the growth phase. In contrast, most of the TEP in E. zodiacus (73%), R. setigera (74%), and Skeletonema sp. (70%) were produced during the stationary and declining phases. The C. granii TEP production rate was highest in the growth phase, whereas those in E. zodiacus, R. setigera, and Skeletonema sp. were highest in the stationary–decline phase. The TEP concentrations per cell and the cell volume of C. granii were 34.97 ± 4.114 (mean ± SD) ng Xeq./cell (xanthan gum equivalents per cell) and 341.6 ± 56.33 fg Xeq./μm3, and were 23.01 and 4.32 times higher than the values obtained from the other three diatoms, respectively. The results suggest
that the mechanisms of TEP production differ with growth stage and diatom species. Therefore, it is likely that the differences
in TEP production among the diatom species influence the complexity of TEP dynamics in aquatic environments. 相似文献
332.
Kosuke SODA Hiroichi OZAKI Hiroshi ITO Tatsufumi USUI Masatoshi OKAMATSU Keita MATSUNO Yoshihiro SAKODA Tsuyoshi YAMAGUCHI Toshihiro ITO 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(12):1891
Large highly pathogenic avian influenza (HPAI) outbreaks caused by clade 2.3.4.4e H5N6 viruses occurred in Japan during the 2016–2017 winter. To date, several reports regarding these outbreaks have been published, however a comprehensive study including geographical and time course validations has not been performed. Herein, 58 Japanese HPAI virus (HPAIV) isolates from the 2016–2017 season were added for phylogenetic analyses and the antigenic relationships among the causal viruses were elucidated. The locations where HPAIVs were found in the early phase of the outbreaks were clustered into three regions. Genotypes C1, C5, and C6–8 HPAIVs were found in specific areas. Two strains had phylogenetically distinct hemagglutinin (HA) and non-structural (NS) genes from other previously identified strains, respectively. The estimated latest divergence date between the viral genotypes suggests that genetic reassortment occurred in bird populations before their winter migration to Japan. Antigenic differences in 2016–2017 HPAIVs were not observed, suggesting that antibody pressure in the birds did not contribute to the selection of HPAIV genotypes. In the late phase, the majority of HPAI cases in wild birds occurred south of the lake freezing line. At the end of the outbreak, HPAI re-occurred in East coast region, which may be due to the spring migration route of Anas bird species. These trends were similar to those observed in the 2010–2011 outbreaks, suggesting there is a typical pattern of seeding and dissemination of HPAIV in Japan. 相似文献