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201.
Journal of Crop Science and Biotechnology - Flooding is one of the major abiotic stresses which accounts for considerable damage to plant growth and development and induces multiple...  相似文献   
202.
Phytoncide, a volatile essential oil produced by plants and trees, has not only anti-microbial activity, but also a stress relieving effect. We prepared a sheath/core type melt-spun fiber that releases phytoncide for a prolonged time. The fiber is comprised of a nylon sheath and a polypropylene (PP) core material. Phytoncide-containing microcapsules are embedded within the core part. The phytoncide microcapsule-containing nylon/PP sheath/core (M-Ny/PP) fiber has suitable mechanical properties for textile application. The phytoncide release from the microcapsule-containing the PP fiber (M-PP) reached a plateau level after 4 days and maintained that level for an additional 7 days, indicating a zero-order release after the initial burst. The M-Ny/PP fiber emitted the volatile phytoncide even though the fiber was spun at 250 °C. The release of phytoncide decreased in the M-Ny/PP fiber compared to the phytoncide microcapsule-containing PP (M-PP) fiber due to the dense sheath layer.  相似文献   
203.
The dyeing and color fastness properties of three reactive-disperse dyes containing a sulphatoethylsulphone group on Nylon, cotton and N/C mixture fabrics were examined. Reduction-clearing was more effective in removing the unfixed dyes than soaping since the reactive-disperse dye became hydrophobic during dyeing process. Nylon was dyed well with three reactive-disperse dyes at pH 5∼8 and difference in chemical structure between dyes did not affect the final color strength of the dyed Nylon fiber, but their build-up properties on Nylon were not so good. The color strength of the dyed cotton was not as high as that of Nylon. The color strength of cotton increased by lowering dyeing temperature when the reactive-disperse dyes having hydroxy group were used. Nylon absorbed more dye molecules than cotton in simultaneous dyeing, the color difference between Nylon and cotton could be reduced as the dyeing temperature decreased. N/C mixture fabric was dyed well at 60 °C with the reactive-disperse dyes having hydroxyl group when applied at pH 7 and 60 °C, and their build-up properties were good. It was also found that washing fastness and rubbing fastness of dyed Nylon, cotton and N/C fabrics with the reactive-disperse dyes were excellent, while light fastness was moderate.  相似文献   
204.
A comparison of poly(trimethylene terephthalate)(PTT) and poly(ethlene terephthalate)(PET) fibers spun at various take-up speeds was presented. Fiber characterization included tensile and thermal properties, optical birefringence, density, sonic modulus, boil-off shrinkage, and wide-angle X-ray diffraction. The phenomenon of stress-induced crystallization was inferred from the X-ray diffraction diagrams for fibers spun with take-up speeds over 4000 m/min. The tenacity and elongation of PTT and PET fiber showed typical results, but the initial modulus of PTT fiber was nearly unchanged over the entire take-up speed range (2000–7000 m/min), whereas that of PET, as expected, increased monotonically with increasing take-up speed. This divergent behavior could be explained by the different molecular deformations in the c-axis as determined from X-ray diffraction patterns. The fiber crystallinity, density, and heat of fusion of both polymers increased with take-up speed. The boil-off shrinkage decreased with increasing take-up speed. The optical birefringence of the two fiber types showed a maximum level at a take-up speed of ca. 5000 m/min. The melting temperature behavior of PTT fiber was different from that of PET fibers. It was found that PTT is less sensitive to stress induced changes at high spinning speeds than is PET.  相似文献   
205.
The effects of scoparone on dopamine release in PC12 cells were investigated. Scoparone at 50–200 µM increased dopamine release into the culture medium. However, the released levels of dopamine by scoparone were not altered in the absence of extracellular Ca2+ and by adenylyl cyclase inhibitor MDL-12,330A. Scoparone increased phosphorylation of PKA, CaMK II and synapsin I. Scoparone also enhanced K+-induced levels of dopamine release by CaMK II phosphorylation. These results suggest that scoparone increases dopamine release by synapsin I phosphorylation via activation of PKA and CaMK II, which are mediated by cyclic AMP levels and Ca2+ influx.  相似文献   
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207.
Five new scalarane sesterterpenoids, felixins A–E (1–5), were isolated from the Formosan sponge Ircinia felix. The structures of scalaranes 1–5 were elucidated on the basis of spectroscopic analysis. Cytotoxicity of scalaranes 1–5 against the proliferation of a limited panel of tumor cell lines was evaluated.  相似文献   
208.
In recent years, several marine-derived compounds have been clinically evaluated. Diterpenes are secondary metabolites from soft coral that exhibit anti-inflammatory, anti-tumor and cytotoxic activities. In the present study, we isolated a natural diterpene product, excavatolide B, from cultured Formosan gorgonian Briareum excavatum and investigated its anti-inflammatory activities. We found that excavatolide B significantly inhibited the mRNA expression of the proinflammatory mediators, inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), in lipopolysaccharide (LPS)-challenged murine macrophages (RAW 264.7). We also examined the anti-inflammatory and anti-nociceptive effects of excavatolide B on intraplantar carrageenan-induced inflammatory responses. Excavatolide B was found to significantly attenuate carrageenan-induced nociceptive behaviors, mechanical allodynia, thermal hyperalgesia, weight bearing deficits and paw edema. In addition, excavatolide B inhibited iNOS, as well as the infiltration of immune cells in carrageenan-induced inflammatory paw tissue.  相似文献   
209.
210.
Echinacea is an allogamous genus, thus its cultivars or populations are genetically heterogeneous. Using amplified fragment length polymorphism (AFLP) to estimate the genetic diversity of Echinacea is generally limited by the large number of individual plants and the higher cost that need to be processed. In the present study, effectiveness of several sizes of DNA bulking (10, 15, 20, 25 and 30 individuals) with 20, 36 and 55 primer pairs was compared using AFLP in determining the genetic diversity of Echinacea species. The results indicated that the use of bulked DNA-based AFLP analysis by using the selected eight primer pairs was capable of detecting genetic diversity between the tested Echinacea species, provided that the potential presence of low frequency variants was ignored and a possible bias in the estimates of genetic similarity was accepted. The assessments showed that a bulk of 15 individuals could detect sufficient AFLP variations at most genomic sites. Additionally, 20 primer pairs could generate sufficient polymorphic fragments to achieve high resolving power of AFLP for the tested Echinacea species.  相似文献   
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