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排序方式: 共有753条查询结果,搜索用时 15 毫秒
681.
Akira?KawakamiEmail author Naoki?Kato Takahide?Sasaya Keisuke?Tomioka Hiroyoshi?Inoue Atsushi?Miyasaka Kazuyuki?Hirayae 《Journal of General Plant Pathology》2015,81(4):324-327
Ear rot with white or pink mold was found on corn (Zea mays L.). A species of Fusarium, not registered previously as a pathogen causing Gibberella ear rot of corn in Japan, was isolated from the rotted ear. The isolates, identified as F. asiaticum based on morphological characteristics and nucleotide sequences, caused white or pink mold on corn ear after inoculation. Moreover, the 3-acetyl deoxynivalenol chemotype and the nivalenol chemotype were found in the isolates. We propose to include F. asiaticum as one of the pathogens causing Gibberella ear rot of corn in Japan. 相似文献
682.
Keitaro Kato Masato Yamamoto Khaoian Peerapon Haruhisa Fukada Amal Biswas Shinji Yamamoto Kenji Takii Shireru Miyashita 《Aquaculture Research》2014,45(11):1818-1824
Taurine is often added to artificial fish diets to compensate for a reduction in fish meal (FM). However, the taurine content of FM‐based diets is typically lower than in diets consisting of raw fish, even in diets where FM is the only protein source. We evaluated the effects of dietary taurine in FM‐based diets on epidermal thickness and scale detachability in red sea bream Pagrus major. We compared the effect of diets containing 0% (control), 0.3% (Tau‐0.3%), 0.6% (Tau‐0.6%) and 1.0% (Tau‐1.0%) taurine. Red sea bream (average body weight, 39 g) were fed these diets for 7 weeks. Taurine supplementation had no effect on growth, feed intake, feeding efficiency, or survival. However, the epidermal thickness was higher in fish in the Tau‐0.6% and Tau‐1.0% groups than in the control and Tau‐0.3% groups. Similarly, scale loss was significantly higher in the control group than in the Tau‐0.6% and Tau‐1.0% groups. Our results suggest that supplementation with >0.6% taurine (1.0% in diet) improves skin condition. 相似文献
683.
684.
Radiation use efficiency,N accumulation and biomass production of high-yielding rice in aerobic culture 总被引:1,自引:0,他引:1
The concept of aerobic culture is to save water resource while maintaining high productivity in irrigated rice ecosystem. This study compared nitrogen (N) accumulation and radiation use efficiency (RUE) in the biomass production of rice crops in aerobic and flooded cultures. The total water input was 800–1300 mm and 1500–3500 mm in aerobic culture and flooded culture, respectively, and four high-yielding rice cultivars were grown with a high rate of N application (180 kg N ha−1) at two sites (Tokyo and Osaka) in Japan in 2007 and 2008. The aboveground biomass and N accumulation at maturity were significantly higher in aerobic culture (17.2–18.5 t ha−1 and 194–233 kg N ha−1, respectively) than in flooded culture (14.7–15.8 t ha−1 and 142–173 kg N ha−1) except in Tokyo in 2007, where the surface soil moisture content frequently declined. The crop maintained higher N uptake in aerobic culture than in flooded culture, because in aerobic culture there was a higher N accumulation rate in the reproductive stage. RUE in aerobic culture was comparable to, or higher than, that in flooded culture (1.27–1.50 g MJ−1 vs. 1.20–1.37 g MJ−1), except in Tokyo in 2007 (1.30 g MJ−1 vs. 1.37 g MJ−1). These results suggest that higher biomass production in aerobic culture was attributable to greater N accumulation, leading to higher N concentration (N%) than in flooded culture. Cultivar differences in response to water regimes were thought to reflect differences in mainly (1) early vigor and RUE under temporary declines in soil moisture in aerobic culture and (2) the ability to maintain high N% in flooded culture. 相似文献
685.
Jiro Otsuka Shutaro Yamaguchi Osamu Chigira Kazutaka Kato 《Journal of Forest Research》2010,15(3):210-216
To determine the viability of hot water emasculation for Acacia auriculiformis, spikes composed of about 100 flowers were soaked in hot water at varying temperatures (45–60°C) and for varying lengths
of time (5 s to 7 min) prior to anthesis. The rate of squashed polyads, each of which consisted of 16 pollen grains, and the
germinating rate on media, decreased with temperature and time. A mating test suggested that the rates of adhering polyads
per stigma and germinating polyads per stigma were lower in the self-pollination of soaked spikes than in that of normal spikes.
On the other hand, the number of matured pods was not significantly different in the mating between the spikes receiving the
soaking treatment (♀) and the spikes receiving no treatment (♂) compared with the mating between normal spikes. Although further
research is needed to determine the optimal treatment conditions, these results suggest that soaking spikes into hot water,
especially at 50°C for 45 s, 54°C for 15 s, and 56°C for 10 s, is an effective emasculation technique. 相似文献
686.
A spectrophotometric assay based on the color reaction between didecyldimethylammonium chloride (DDAC) and 4-[4-(dipropylamino)phenylazo]-benzenesulfonic acid (propyl orange) was used for the determination of DDAC as a wood preservative. The assay was carried out using a propyl orange solution at pH 2.9. The visible absorbance spectrum of propyl orange showed an absorbance maximum at 510 nm, which decreased continuously with increasing DDAC concentration from 0 to 20 ppm. A linear correlation was observed at a DDAC concentration lower than 8 ppm. To apply this assay method to determine DDAC retention in treated wood, the influence of wood extractives on the assay was investigated. Wood extractives from sapwood and heartwood of Japanese cedar, Hinoki cypress, Japanese larch, and Western hemlock showed no influence on DDAC determination except in the case of heartwood from Japanese cedar and Hinoki cypress, which gave apparent DDAC concentrations higher than the actual values. However, it was also found that absorbance measurement at 477 nm solved this overestimation and gave precise values. It was concluded that this assay is a viable alternative to the current methods for DDAC determination. 相似文献
687.
A triploid hybrid, which was obtained from interspecific crosses between tetraploid Primula denticulata (2n = 4x = 44) and P. rosea (2n = 2x = 22), successfully produced 11 plants by backcrossing with pollen of tetraploid P. denticulata. Analysis of ploidy level using flow cytometry and chromosome counting in the 11 BC1 plants revealed that all progeny had much larger DNA contents and chromosome number than both parents. In this triploid-tetraploid
(3x–4x) crossing, progeny was predominantly true or near pentaploid presumably produced by the fertilization between true
or near triploid female gamete produced from triploid hybrid and diploid pollen of tetraploid P. denticulata. These results suggest that unreduced (3x) or near triploid female gametes were partially produced by single step meiosis,
either first-division restitution or second-division restitution process. The zygotes formed by the fertilization between
true or near triploid egg produced by single step meiosis in triploid hybrid and diploid pollen produced by normal meiosis
of tetraploid P. denticulata might be the only survivors in embryogenesis. 相似文献
688.
Haruyama J Ohtake M Matsunaga T Morota T Honda C Yokota Y Abe M Ogawa Y Miyamoto H Iwasaki A Pieters CM Asada N Demura H Hirata N Terazono J Sasaki S Saiki K Yamaji A Torii M Josset JL 《Science (New York, N.Y.)》2009,323(5916):905-908
We determined model ages of mare deposits on the farside of the Moon on the basis of the crater frequency distributions in 10-meter-resolution images obtained by the Terrain Camera on SELENE (Selenological and Engineering Explorer) (Kaguya). Most mare volcanism that formed mare deposits on the lunar farside ceased at approximately 3.0 billion years ago, suggesting that mare volcanism on the Moon was markedly reduced globally during this period. However, several mare deposits at various locations on the lunar farside also show a much younger age, clustering at approximately 2.5 billion years ago. These young ages indicate that mare volcanism on the lunar farside lasted longer than was previously considered and may have occurred episodically. 相似文献
689.
Identification and molecular mapping of Flowering Date1 (FD1), a major photoperiod insensitivity gene in the adzuki bean (Vigna angularis)
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Hiroki Yamamoto Yuki Horiuchi Reina Ogura Hiroaki Sakai Hitoshi Sato Kiyoaki Kato 《Plant Breeding》2016,135(6):714-720
The induction of flowering under long‐day conditions is an important adaptation by short‐day plants, such as adzuki beans (Vigna angularis), to high‐latitude environments. This study clarified the genetic control underlying the long‐day insensitivity of adzuki bean cultivar ‘Shumari’. ‘Shumari’ was found to be insensitive to a 16‐h day, whereas landrace Acc2265 was highly sensitive. When grown under natural long‐day conditions at Obihiro (42°9′N), Acc2265 initiated flowering at least 80 days after ‘Shumari’. When 86 recombinant inbred lines (RILs) derived from crosses between ‘Shumari’ and Acc2265 were grown under these conditions, their flowering dates ranged from the middle of July to the end of October. The distinct bimodal distribution in the RIL population was due to a single major gene, designated Flowering Date1 (FD1). Molecular mapping showed that FD1 was located between the SSR markers Az02‐37M3 and Az02‐40M9, at distances of 6 and 10.4 cM, respectively, on linkage group 2. RILs carrying FD1S lacked long‐day sensitivity, whereas RILs carrying FD1A were sensitive to long‐day conditions, confirming that FD1 controls long‐day sensitivity. 相似文献
690.