全文获取类型
收费全文 | 366篇 |
免费 | 16篇 |
专业分类
林业 | 46篇 |
农学 | 14篇 |
60篇 | |
综合类 | 15篇 |
农作物 | 12篇 |
水产渔业 | 20篇 |
畜牧兽医 | 179篇 |
园艺 | 9篇 |
植物保护 | 27篇 |
出版年
2023年 | 1篇 |
2022年 | 6篇 |
2021年 | 7篇 |
2020年 | 5篇 |
2019年 | 4篇 |
2018年 | 6篇 |
2017年 | 4篇 |
2016年 | 11篇 |
2015年 | 9篇 |
2014年 | 13篇 |
2013年 | 25篇 |
2012年 | 20篇 |
2011年 | 20篇 |
2010年 | 19篇 |
2009年 | 11篇 |
2008年 | 19篇 |
2007年 | 19篇 |
2006年 | 27篇 |
2005年 | 28篇 |
2004年 | 16篇 |
2003年 | 18篇 |
2002年 | 15篇 |
2001年 | 21篇 |
2000年 | 11篇 |
1999年 | 12篇 |
1998年 | 6篇 |
1997年 | 4篇 |
1996年 | 1篇 |
1995年 | 1篇 |
1992年 | 6篇 |
1991年 | 4篇 |
1990年 | 4篇 |
1989年 | 1篇 |
1987年 | 2篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1983年 | 3篇 |
1980年 | 1篇 |
排序方式: 共有382条查询结果,搜索用时 15 毫秒
221.
The aim of this study was to elucidate the mechanisms of deformation change of bamboo set during bending with repeated moisturizing and drying. Deformation was represented by the set ratio, defined as the camber height normalized by the initial value of the fixed set. Susceptibility to deformation from moisture changes was estimated by the slope of the plot of the set ratio versus the moisture content. The set ratio decreased gradually during the repetition of moisturizing and drying, a property consistent with general wood materials. When the specimens were previously extracted in hot water, the set ratio increased but the slope did not change. On the other hand, a previous thermal treatment at more than 230°C or a set at less than 60°C affected both the set ratio and the slope: The set ratio decreased, and the slope increased. It is known that at 60°C hemicellulose starts to soften and at 230° C thermal degradation occurs. Thus, hemicellulose may play a role in the deformation properties of bamboo set during bending.Part of this report was presented at the 50th annual meeting of the Japan Wood Research Society, April 2000, Kyoto 相似文献
222.
Takanori Imai Hideyuki Goto Hiroyuki Matsumura Seiichi Yasuda 《Journal of Wood Science》1999,45(2):164-169
To radiolabel xylan in mature cell walls selectively, magnolia (Magnolia kobus DC.) was administered withmyo-inositol-[2-3H] and allowed to metabolize for 1 month. The radiolabeled xylem tissue was then submitted to sulfuric acid hydrolysis and nitrobenzene oxidation. A large amount of radioactivity was found mainly in xylose, although slight activities were detected in glucose and in vanillin and syringaldehyde. The labeled tissue was submitted to a preparation of holocellulose followed by treatment with 24% potassium hydroxide (KOH). Radioactivity was distributed mainly in the KOH-soluble part of the holocellulose. These results indicate that most radioactivity was incorporated into xylan in the cell walls. The distribution of the incorporated radioactivity in the xylem tissue was visualized by microautoradiography. Radioactivities were distributed in the xylem more than 400 m from the cambium; and an inner layer of a secondary wall had formed at the labeled xylem. Consequently, selective radio-labeling of xylan was visualized in mature cell walls.Part of this report was presented at the 47th annual meeting of the Japan Wood Research Society, Kouchi, April 1997 相似文献
223.
Hirofumi?HiraiEmail author Takanori?Itoh Tomoaki?Nishida 《Journal of Wood Science》2003,49(6):538-542
Reduction of manganese dioxide is demonstrated for an in vitro ferrireductase system that includes NADPH-dependent ferrireductase and the iron-binding compound (IBC) isolated from the white-rot fungus Phanerochaete sordida YK-624. The Fe(II)–IBC complex was more effective in reducing manganese dioxide to Mn(II) than were complexes of Fe(II) and organic acids of low molecular weight such as nitrilotriacetate, although IBC also reduced manganese dioxide to Mn(II) in the absence of Fe(II). The generated Fe(III)–IBC complex was a better substrate for NADPH-dependent ferrireductase than were other ferric chelates, suggesting that the Fe(III)–IBC complex is reduced to an Fe(II) complex by NADPH-dependent ferrireductase. Moreover, production of the Fe(III)–IBC complex by the reduction of manganese dioxide in a reaction system containing Fe(II) and IBC was observed to be coupled to reduction of the Fe(III)–IBC complex by NADPH-dependent ferrireductase. These results indicate that the ferrireductase system of P. sordida YK-624 plays an important role in the reduction of manganese dioxide, which is necessary for the production and function of manganese peroxidase. 相似文献
224.
The fatigue life of structural plywood under two-stage panel shear load was experimentally examined. Two experimental conditions
were determined for two-stage fatigue of plywood specimen: one used variable applied stress and the other used variable stress,
loading waveform, and loading frequency, because fatigue life of wood composite under constant load depended on loading waveform
and loading frequency as well as stress level. The most famous cumulative fatigue damage theory is the Palmgren-Miner rule,
which is the summation of the ratio of the applied loading cycle to the fatigue life under each loading stage. However, the
applicability of this rule to the two-stage fatigue of wood composites has not been investigated. It was first demonstrated
in this study that the fatigue life of the plywood specimen reached in the two-stage fatigue test did not obey the Palmgren-Miner
rule. Here, we propose the new cumulative fatigue damage model by modification of the Palmgren-Miner rule on the basis of
the assumption that fatigue damage accumulates with loading cycle on a logarithmic scale. The newly proposed model was in
good agreement with the fatigue life reached in the two-stage fatigue test. 相似文献
225.
To establish an experimental approach for studying the biosynthetic pathway of agatharesinol, a norlignan, induction of the
formation of agatharesinol in Cryptomeria japonica (Japanese cedar, sugi) was attempted. Wood sticks were prepared from the sapwood immediately after cutting a sugi tree down,
and they were allowed to stand in desiccators in which the humidity was adjusted to 76% and 88%, and in a room. When the wood
sticks were allowed to stand in 76% humidity and in a room, they dried rapidly and no formation of agatharesinol was demonstrated
by gas chromatography-mass spectrometry. These results suggest that in the sapwood dried rapidly, the cells that were biologically
active in the sapwood, probably ray parenchyma cells, die rapidly and completely before the biosyntheses of secondary metabolites
including agatharesinol was wholly established. The wood sticks allowed to stand in 88% humidity, on the other hand, dried
gradually compared with the sticks placed in 76% humidity and in a room, and agatharesinol was formed as one of the predominant
ethyl acetate extractives. These results suggest that delaying the drying of the sapwood sticks can control the dying period
to an appropriate length for the ray parenchyma cells, during which the biosynthesis of agatharesinol is induced.
Part of this study was presented at the 54th Annual Meeting of the Japan Wood Research Society, Sapporo, August 2004 相似文献
226.
Takuma Aoki Hiroo Madarame Keisuke Sugimoto Hiroshi Sunahara Yoko Fujii Eiichi Kanai Tetsuro Ito 《The Canadian veterinary journal. La revue veterinaire canadienne》2015,56(7):745-748
We report the case of a 4-year-old, castrated 4.2-kg Scottish fold cat with recurrent epistaxis that was unresponsive to medical therapy. Diathermocoagulation of the nasal mucosa with a diode laser controlled the epistaxis and there was no significant recurrence of epistaxis during 1 year of follow-up. 相似文献
227.
A comparative study of zinc protoporphyrin IX‐forming properties of animal by‐products as sources for improving the color of meat products 下载免费PDF全文
The objective of this study was to obtain fundamental data for improving the color of meat products by using animal by‐products. We investigated zinc protoporphyrin IX (ZnPP)‐forming properties of various internal organs from pigs and chickens. ZnPP was formed in the liver, heart and kidney, whereas the porcine spleen and bile, which are involved in the metabolism of heme, did not have ZnPP‐forming properties. The optimum pH values were different among the internal organs and the ZnPP‐forming properties of porcine organs were better than those of chicken organs. The porcine liver showed the greatest ZnPP‐forming properties among all of the internal organs investigated in this study. The optimum pH value for ZnPP formation in the liver was lower than that of skeletal muscle. Oxygen did not inhibit the formation of ZnPP in the liver, unlike in skeletal muscle. Animal by‐products such as the liver have good ability for the formation of ZnPP and might be useful for improving the color of meat products. 相似文献
228.
The importance of subfragment 2 and C‐terminus of myosin heavy chain for thick filament assembly in skeletal muscle cells 下载免费PDF全文
Koichi Ojima Mika Oe Ikuyo Nakajima Masahiro Shibata Susumu Muroya Koichi Chikuni Akihito Hattori Takanori Nishimura 《Animal Science Journal》2015,86(4):459-467
In skeletal muscle cells, myofibrillar proteins are highly organized into sarcomeres in which thick filaments interdigitate with thin filaments to generate contractile force. The size of thick filaments, which consist mainly of myosin molecules, is strictly controlled. However, little is known about the mechanisms by which myosin molecules assemble into thick filaments. Here, we assessed the ability of each domain of myosin heavy chain (Myh) to form thick filaments. We showed that exogenously expressed subfragment 2 (S2) + light meromyosin (LMM) of Myh was efficiently incorporated into thick filaments in muscle cells, although neither solely expressed S2 nor LMM targeted to thick filaments properly. In nonmuscle COS7 cells, S2+LMM formed more enlarged filaments/speckles than LMM. These results suggest that Myh filament formation is induced by S2 accompanying LMM. We further examined the effects of Myh C‐terminus on thick filament assembly. C‐terminal deletion mutants were incorporated not into entire thick filaments but rather into restricted regions of thick filaments. Our findings suggest that the elongation of myosin filaments to form thick filaments is regulated by S2 as well as C‐terminus of LMM. 相似文献
229.
230.
Development of loop-mediated isothermal amplification (LAMP) method for diagnosis of equine piroplasmosis 总被引:1,自引:0,他引:1
Alhassan A Thekisoe OM Yokoyama N Inoue N Motloang MY Mbati PA Yin H Katayama Y Anzai T Sugimoto C Igarashi I 《Veterinary parasitology》2007,143(2):155-160
Loop-mediated isothermal amplification (LAMP) is a novel nucleic acid method whereby DNA is amplified with high specificity, efficiency, and rapidity under isothermal conditions using a set of four specifically designed primers and a DNA polymerase with strand displacement activity. In this study, we used LAMP primer sets designed from EMA-1 and Bc 48 genes for detection of Theileria equi and Babesia caballi infections, respectively. These primer sets specifically amplified DNA of the respective parasites. Both primer sets amplified T. equi and B. caballi up to 10(-6) dilution of 10-fold serially diluted samples. Furthermore, DNA extracted from blood collected from a horse experimentally infected with T. equi was amplified by a T. equi LAMP primer set from days 2 to 35 post-infection, demonstrating the high sensitivity of these primers. Of 55 samples collected from China, 81.8% and 56.3% were positively detected by LAMP for T. equi and B. caballi infections, respectively. In contrast, 91.8% and 45.9% of the 37 samples collected from South Africa were LAMP positive for T. equi and B. caballi, respectively. These results suggest that LAMP could be a potential diagnostic tool for epidemiological studies of equine piroplasmosis. 相似文献