全文获取类型
收费全文 | 63篇 |
免费 | 0篇 |
专业分类
林业 | 22篇 |
农学 | 8篇 |
5篇 | |
综合类 | 10篇 |
农作物 | 1篇 |
畜牧兽医 | 8篇 |
园艺 | 2篇 |
植物保护 | 7篇 |
出版年
2021年 | 3篇 |
2018年 | 1篇 |
2017年 | 1篇 |
2016年 | 1篇 |
2015年 | 4篇 |
2014年 | 3篇 |
2013年 | 3篇 |
2012年 | 2篇 |
2011年 | 10篇 |
2010年 | 1篇 |
2009年 | 3篇 |
2008年 | 1篇 |
2007年 | 6篇 |
2006年 | 3篇 |
2005年 | 6篇 |
2004年 | 3篇 |
2002年 | 1篇 |
2001年 | 2篇 |
2000年 | 1篇 |
1997年 | 4篇 |
1996年 | 1篇 |
1989年 | 1篇 |
1985年 | 1篇 |
1979年 | 1篇 |
排序方式: 共有63条查询结果,搜索用时 171 毫秒
1.
Yunting?FangEmail author Per?Gundersen Rolf?D.?Vogt Keisuke?Koba Fusheng?Chen Xi?Yun?Chen Muneoki?Yoh 《Journal of Forest Research》2011,16(5):341-350
Data have been compiled from published sources on nitrogen (N) fluxes in precipitation, throughfall, and leaching from 69
forest ecosystems at 50 sites throughout China, to examine at a national level: (1) N input in precipitation and throughfall,
(2) how precipitation N changes after the interaction with canopy, and (3) whether N leaching increases with increasing N
deposition and, if so, to what extent. The deposition of dissolved inorganic N (DIN) in precipitation ranged from 2.6 to 48.2 kg N ha−1 year−1, with an average of 16.6 kg N ha−1 year−1. Ammonium was the dominant form of N at most sites, accounting for, on average, 63% of total inorganic N deposition. Nitrate
accounted for the remaining 37%. On average, DIN fluxes increased through forest canopies, by 40% and 34% in broad-leaved
and coniferous forests, respectively. No significant difference in throughfall DIN inputs was found between the two forest
types. Overall, 22% of the throughfall DIN input was leached from forest ecosystems in China, which is lower than the 50–59%
observed for European forests. Simple calculations indicate that Chinese forests have great potential to absorb carbon dioxide
from the atmosphere, because of the large forest area and high N deposition. 相似文献
2.
3.
4.
Two disomic barley chromosome addition lines and five translocated chromosome addition lines of common wheat cultivar Shinchunaga
were isolated. They were derived from a hybrid plant between Shinchunaga and cultivated barley Nyugoruden (New Golden) by
backcrossing with wheat and self pollination. Barley chromosomes added to chromosome arms involved in the translocated chromosomes
were identified by C-banding method and by crossing these lines with Chinese Spring/Betzes addition lines. Two disomic addition
lines were identified to have chromosome 6 and 7 of barley, respectively. Two of the five translocated chromosome addition
lines were clarified to have same chromosome constitution, 42 wheat chromosomes and a pair of translocated chromosomes constituted
with a long arm of chromosome 5B of wheat and a short arm of chromosome 7 of barley. The other three lines could not be identified
due to chromosome rearrangement. Performances of these seven lines on agronomic characters were examined. Addition of barley
chromosome 7 induced early heading, and chromosome 6 showed lated heading. Almost all of the lines except that of chromosome
6 showed short culm length and all showed reduced number of tillers, spikelets and grains per ear, and low seed fertility.
These lines would be useful for genetic analyses in wheat and barley and for induction of useful genes of barley into wheat.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
5.
The effectiveness of Denapon and Ethrel as a thinning chemical for ‘Muscat of Alexandria’ grape was examined from 1980 to 1982 with various timings and concentrations of application. Ethrel applied at 50 mg l?1 by cluster-dipping or shoot-spraying at full bloom, or 6 days after full bloom, resulted in over-thinning and chemical injury, and no thinning effect was found when Ethrel was applied at 10 or 5 mg l?1 on the same dates. The only treatment which exhibited a desirable thinning effect was shoot-spraying at 50 mg l?1 12 days after full bloom, but this markedly inhibited berry growth. Denapon applied at 1667 mg l?1 by shoot-spraying at full bloom, or 6 days after full bloom, reduced the number of berries per cluster almost adequately and consistently without any unfavorable side effects. This chemical applied at 834 mg l?1 was nearly as effective as when applied at 1667 mg l?1, but the effectiveness of the former was less consistent than that of the latter. From these results, Denapon is thought to be a promising thinning chemical for ‘Muscat of Alexandria’. 相似文献
6.
Russell CA Jones TC Barr IG Cox NJ Garten RJ Gregory V Gust ID Hampson AW Hay AJ Hurt AC de Jong JC Kelso A Klimov AI Kageyama T Komadina N Lapedes AS Lin YP Mosterin A Obuchi M Odagiri T Osterhaus AD Rimmelzwaan GF Shaw MW Skepner E Stohr K Tashiro M Fouchier RA Smith DJ 《Science (New York, N.Y.)》2008,320(5874):340-346
Antigenic and genetic analysis of the hemagglutinin of approximately 13,000 human influenza A (H3N2) viruses from six continents during 2002-2007 revealed that there was continuous circulation in east and Southeast Asia (E-SE Asia) via a region-wide network of temporally overlapping epidemics and that epidemics in the temperate regions were seeded from this network each year. Seed strains generally first reached Oceania, North America, and Europe, and later South America. This evidence suggests that once A (H3N2) viruses leave E-SE Asia, they are unlikely to contribute to long-term viral evolution. If the trends observed during this period are an accurate representation of overall patterns of spread, then the antigenic characteristics of A (H3N2) viruses outside E-SE Asia may be forecast each year based on surveillance within E-SE Asia, with consequent improvements to vaccine strain selection. 相似文献
7.
Circadian rhythms. Daily watch on metabolism 总被引:1,自引:0,他引:1
8.
Sugita S Ootsubo T Kadono T Honda M Sako S Miyata T Sakon I Yamashita T Kawakita H Fujiwara H Fujiyoshi T Takato N Fuse T Watanabe J Furusho R Hasegawa S Kasuga T Sekiguchi T Kinoshita D Meech KJ Wooden DH Ip WH A'Hearn MF 《Science (New York, N.Y.)》2005,310(5746):274-278
The impact cratering process on a comet is controversial but holds the key for interpreting observations of the Deep Impact collision with comet 9P/Tempel 1. Mid-infrared data from the Cooled Mid-Infrared Camera and Spectrometer (COMICS) of the Subaru Telescope indicate that the large-scale dust plume ejected by the impact contained a large mass (approximately 10(6) kilograms) of dust and formed two wings approximately +/-45 degrees from the symmetric center, both consistent with gravity as the primary control on the impact and its immediate aftermath. The dust distribution in the inner part of the plume, however, is inconsistent with a pure gravity control and implies that evaporation and expansion of volatiles accelerated dust. 相似文献
9.
Satoshi AKAGI Seiya TAKAHASHI Katsuhiro OHKOSHI Takato TAKENOUCHI Manabu SHIMIZU Masaya GESHI Noritaka ADACHI Dai‐ichiro FUCHIMOTO Yoshiaki IZAIKE Hisashi ASO 《Animal Science Journal》2002,73(6):465-469
The developmental potential of nuclei from a bovine mammary epithelial cell line (BMEC) in nuclear transfer was investigated. For nuclear transfer donors, BMEC cells (passage 15) were cultured for 4–5 days after seeding at cell densities of 1.0 × 105 cells/cm2 (high‐density group) or 0.8 × 104 cells/cm2 (low‐density group). First, the effective electric stimulation for fusion of enucleated oocytes with BMEC cells was examined. Fusion rates reached maximum with two DC pulses of 30 V/150 µm for 20 µs in the high‐density group and with two DC pulses of 25 V/150 µm for 10 µs in the low‐density group. The fusion rate (37.5%) in the high‐density group was significantly (P < 0.005) lower than in the low‐density group (71.4%). Second, the in vitro developmental potential of nuclear transfer embryos derived from BMEC cells was examined. In the high‐density and low‐density groups, 18.8% and 24.1% of fused oocytes, respectively, developed to blastocyst stage. The results of this study indicate that nuclei from BMEC cells support the development of nuclear transfer embryos to the blastocyst stage and that the efficiency of oocyte–cell fusion is affected by the culture conditions of the donor BEMC cells before nuclear transfer. 相似文献
10.
Kitani H Yoshioka M Takenouchi T Sato M Yamanaka N 《Veterinary immunology and immunopathology》2011,140(3-4):341-345
Previously, we developed a simple and efficient method to isolate liver macrophages from a mixed primary culture of adult rat liver cells. To extend the applicability of this method, we isolated macrophages from mixed primary cultures of bovine liver cells. Macrophage cells proliferated on the cell sheet of mixed bovine liver cells after 8-16d of culture. These cells were detached by shaking of the culture flasks. Subsequent transfer and brief incubation in plastic dishes resulted in selective adhesion of macrophages. After rinses with PBS, attached macrophages were harvested. More than 10(6) cells could be harvested from the culture flask at intervals of 2-3d for more than three weeks. The isolated cells were strongly positive for bovine macrophage markers, such as CD68, CD172a and Iba-1. These cells exhibited functional properties of macrophages, including active phagocytosis of polystyrene microbeads, proliferative response to recombinant bovine granulocyte-macrophage colony-stimulating factor, upregulation of specific inflammatory cytokine genes upon stimulation with lipopolysaccharide, and formation of multinucleated giant cells. The shaking and attachment method provides a simple and efficient alternative to obtain bovine liver macrophages without requiring complex equipment or specialized technical skills. 相似文献