全文获取类型
收费全文 | 559篇 |
免费 | 14篇 |
国内免费 | 2篇 |
专业分类
林业 | 49篇 |
农学 | 14篇 |
42篇 | |
综合类 | 36篇 |
农作物 | 21篇 |
水产渔业 | 57篇 |
畜牧兽医 | 319篇 |
园艺 | 4篇 |
植物保护 | 33篇 |
出版年
2022年 | 6篇 |
2021年 | 6篇 |
2020年 | 6篇 |
2019年 | 8篇 |
2018年 | 6篇 |
2017年 | 10篇 |
2016年 | 10篇 |
2015年 | 12篇 |
2014年 | 11篇 |
2013年 | 21篇 |
2012年 | 28篇 |
2011年 | 26篇 |
2010年 | 22篇 |
2009年 | 17篇 |
2008年 | 35篇 |
2007年 | 43篇 |
2006年 | 29篇 |
2005年 | 30篇 |
2004年 | 20篇 |
2003年 | 21篇 |
2002年 | 18篇 |
2001年 | 11篇 |
2000年 | 16篇 |
1999年 | 5篇 |
1998年 | 11篇 |
1997年 | 3篇 |
1992年 | 12篇 |
1991年 | 9篇 |
1990年 | 10篇 |
1989年 | 14篇 |
1988年 | 7篇 |
1987年 | 13篇 |
1986年 | 9篇 |
1985年 | 7篇 |
1984年 | 6篇 |
1983年 | 2篇 |
1982年 | 3篇 |
1981年 | 4篇 |
1980年 | 4篇 |
1979年 | 8篇 |
1978年 | 5篇 |
1977年 | 3篇 |
1976年 | 3篇 |
1975年 | 2篇 |
1973年 | 4篇 |
1972年 | 2篇 |
1971年 | 3篇 |
1970年 | 2篇 |
1967年 | 2篇 |
1963年 | 1篇 |
排序方式: 共有575条查询结果,搜索用时 0 毫秒
571.
S Katayama M Yamanaka S Ota Y Shimizu 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》1999,61(4):411-416
We have developed a new quantitative method for rabies virus (RV) detection using enzyme-linked immunosorbent assay (ELISA). The method named N-ELISA was based on the quantitation of nucleoprotein (N) in RV virions captured by RV-specific polyclonal antibodies on an ELISA plate. Both infective and defective interfering (DI) particles of RV could be detected by this method. When viruses were propagated in a medium of pH 7.4 adjusted with 7% NaHCO3, N-ELISA could detect them with titers of more than 10(6) pfu/ml, though the result did not correlate highly with that of the infectivity assay. The reason for this was considered to be that RVs included spikeless and damaged particles which were produced under conditions of low or high pH. However, in the time course of virus yield, titers of N-ELISA correlated well with those of the infectivity assay. 相似文献
572.
Wide hybridization that cannot be attained through conventional sexual crosses, can now be approached by somatic hybridization.
Protoplasts of I. ensata and I. germanica were fused by electrofusion. For the selection of somatic hybrids, protoplasts of
I. ensata which did not form colonies in protoplast culture and protoplasts of I. germanica which had regeneration ability
for only albino shoot were used in symmetric fusion. On the other hand, the protoplasts of I. ensata and I. germanica protoplasts
which were inactivated by iodoacetamide (IOA) treatment were used in asymmetric fusion. Five-six months after cell fusion,
green plants were obtained in the symmetric and asymmetric fusion. In the random amplified polymorphic DNA (RAPD) analysis,
the green plants had bands specific to both parental species. Therefore, these plants were somatic hybrids between I. ensata
and I. germanica.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
573.
Previous studies have suggested that melting processes are responsible for the trace element variability observed in olivine-hosted basaltic melt inclusions. Melt inclusions from three individual lava samples (two from Mangaia, Cook Islands, and one from Tahaa, Society Islands) have heterogeneous Pb isotopic compositions, even though the erupted lavas are isotopically homogeneous. The range of Pb isotopic compositions from individual melt inclusions spans 50 percent of the worldwide range observed for ocean island basalts. The melt inclusion data can be explained by two-component mixing for each island. Our data imply that magmas with different isotopic compositions existed in the volcanic plumbing system before or during melt aggregation. 相似文献
574.
Sayaka Sogawa Kiyotaka Hidaka Yasuhiro Kamimura Masanori Takahashi Hiroaki Saito Yuji Okazaki Yugo Shimizu Takashi Setou 《Fisheries Oceanography》2019,28(4):454-467
The sustainable use of marine resources requires understanding the surrounding ecosystem and elucidating mechanisms of variation. However, we still lack a comprehensive understanding of environmental variation in the spawning and nursery grounds of important fisheries species Japanese sardine (Sardinops melanostictus) and mackerels (Scomber japonicus and Scomber australasicus) in the northwest Pacific. Here, we investigate detailed physical, chemical, and biological environment variations in the spawning and nursery grounds along the Kuroshio and Kuroshio Extension area from intensive investigation in spawning season (April) of 2013. We found similar water mass property and copepod community in the egg‐rich Kuroshio area and the larvae‐rich downstream Kuroshio Extension area, indicating environmental variability is small during transportation and development processes. The egg‐rich northern Izu Islands region showed high copepod abundance, although low nutrient and chlorophyll concentrations were observed. Eggs were scarce or absent in the second survey 10 days after abundant eggs were observed in the region, along with differences in water property and copepod community. This indicates that not only the location but also the specific water characteristic and copepod community are a determining factor for spawning. Indicator communities of copepod found in our study (indicator community of transportation process from spawning ground, of non‐spawning ground, and of reproductive area in the Kuroshio Extension area) would be a key factor for recruitment prediction. 相似文献
575.
Toshihiko Saito Ikutaro Shimizu Jiro Seki Toshiki Kaga Eiichi Hasegawa Hiromi Saito Kazuya Nagasawa 《Fisheries Science》2010,76(6):909-920
To examine the efficacy of juvenile salmon research as a tool for forecasting adult returns, the results from a study on the
early marine life stage of juvenile chum salmon, conducted in the Nemuro Strait during 1999–2002 (i.e., 1998–2001 brood years),
were compared with the return rates of adult salmon. Among the four brood years, the 2000 brood year (i.e., salmon migrating
to the sea in 2001) was previously reported as showing higher abundance, higher growth rate and better somatic condition during
the coastal residency period. Consequently, we expected it to have the highest return rate, under a hypothesis that juvenile
survival in coastal residency regulates brood-year strength. Contrary to this expectation, the 2000 brood year had almost
the lowest return rate. Alternatively, a statistical model in which sea surface temperature during the first year of marine
life and size at release were utilized as explanatory variables reconstructed the actual variability in return rates more
accurately than that based on the early marine life stage. Possible reasons for the discrepancy between the results of the
juvenile salmon research and adult returns are discussed, and we suggest improvements for future research on juvenile salmon. 相似文献