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351.
352.
Transverse paraffin sections of mature greenwood stems of rose (Rosa x hybrida) and flowering dogwood (Cornus florida L.) were stained with Bismarck brown followed by azure B or tolnidine blue O. The Bismarck brown was replaced by thiazin dye metachromasia in all structures except the cuticle which remained brown or yellow. The interface between the cuticle and exterior cell walls of the epidermis was delineated clearly.  相似文献   
353.
 Vesicular-arbuscular mycorrhizal (VAM) colonization can alter transpiration of host leaves, but scientists remain unclear about the mechanisms involved. We tested whether intact root systems were required to observe effects of root colonization by Glomus intraradices on leaf transpiration, or whether some VAM influence resided in leaves even after they were detached from root systems. We measured the transpiration of detached leaves of VAM and nonmycorrhizal plants exposed to different levels of several substances known to influence stomata locally or act in whole-plant regulation of transpiration: abscisic acid, calcium, phosphorus, and hydrogen ions. In rose, some VAM influence on transpiration resided in leaves, even after they had been separated from their root systems. However, removing leaves from their root systems eliminated the VAM influence on stomatal behavior of cowpeas. Accepted: 22 June 1998  相似文献   
354.
Tracer 120SC is effective against several insect pests of different crops, but it may be phytotoxic. The objective of this study was to quantify the phytotoxic effect of Tracer 120SC on rose. Phtotoxicity of Tracer 120SC was tested at three rates. A single application of Tracer 120SC caused acute phytotoxic damage to leaves, shoots and flower stalks at all tested rates. Two to three days after spraying symptoms were observed on 32.2 to 52.0% of sprayed shoots, with severity of 26 to 38%. Damage on individual shoots without flower buds varied between 21.1 and 37.6%. Similarly, the proportion of damaged leaves per flower stalk ranged from 57.8 to 62.3%. Flower damage was highest of any tissue, with 79.5 to 90% of tissue exhibiting phytotoxic symptoms. Taken together all flower stalks exhibited damage and were not marketable.  相似文献   
355.
Under field conditions, plants are often simultaneously exposed to several abiotic and biotic stresses resulting in significant reductions in growth and yield; thus, developing a multi-stress tolerant variety is imperative. Previously, we reported the neofunctionalization of a novel PNP family protein, Putranjiva roxburghii purine nucleoside phosphorylase (PRpnp) to trypsin inhibitor to cater to the needs of plant defence. However, to date, no study has revealed the potential role and mechanism of either member of this protein group in plant defence. Here, we overexpressed PRpnp in Citrus aurantifolia which showed nuclear-cytoplasmic localization, where it functions in maintaining the intracellular purine reservoir. Overexpression of PRpnp significantly enhanced tolerance to salt, oxidative stress, alkaline pH, drought and two pests, Papilio demoleus and Scirtothrips citri in transgenic plants. Global gene expression studies revealed that PRpnp overexpression up-regulated differentially expressed genes (DEGs) related to ABA- and JA-biosynthesis and signalling, plant defence, growth and development. LC–MS/MS analysis validated higher endogenous ABA and JA accumulation in transgenic plants. Taken together, our results suggest that PRpnp functions by enhancing the endogenous ABA and JA, which interact synergistically and it also inhibits trypsin proteases in the insect gut. Also, like other purine salvage genes, PRpnp also regulates CK metabolism and increases the levels of CK-free bases in transgenic Mexican lime. We also suggest that PRpnp can be used as a potential candidate to develop new varieties with improved plant vigour and enhanced multiple stress resistance.  相似文献   
356.
Eight species of the genus Macrosiphum Passerini 1860 (Sternorrhyncha: Aphididae) are recognized from the Korean Peninsula. A new species, Macrosiphum ( Macrosiphum ) paektusani n. sp., is described herein for apterous and alate viviparous females on Rosa marretii Lev. (Rosaceae). The taxonomic position of Macrosiphum ( Macrosiphum ) cornifoliae Shinji 1924, com. rev., is transferred from the genus Sitobion Mordvilko 1914 to its original position. Host plants of the Korean Macrosiphum are reviewed and the identification key to subgenera and species is also presented.  相似文献   
357.
Transverse paraffin sections of mature greenwood stems of rose (Rosa x hybrida) and flowering dogwood (Cornus florida L.) were stained with Bismarck brown followed by azure B or tolnidine blue O. The Bismarck brown was replaced by thiazin dye metachromasia in all structures except the cuticle which remained brown or yellow. The interface between the cuticle and exterior cell walls of the epidermis was delineated clearly.  相似文献   
358.
Cyclophosphamide (CYP) is a widely used antineoplastic and immunosuppressive drug, however, despite its efficacy, it has shown extensive multiple organ toxicities, including peripheral neuropathy which significantly affects the quality of life of cancer patients. This study elucidated the protective properties of Shorea roxburghii polyphenol extract (SLPE) in CYP-induced peripheral neuropathy. Rats were treated with SLPE (100 and 400 mg/kg) for five weeks plus CYP once a week from the second week of SLPE treatment. Using UHPLC-QTOF-MS, 54 polyphenolic compounds were identified in SLPE extract. After the treatment period the antinociceptive, anti-hyperalgesia and antiallodynic effects was evaluated using formalin paw edema, acetic acid abdominal writhing, hot plate, tail immersion and von Frey filament tests. While the locomotive and motor coordination effects were evaluated by open field and rotarod tests. The administration of CYP led to significant increases in mechanical and thermal hyperalgesia, in addition to hyper-nociceptive responses in the formalin and acetic acid writhing tests. CYP also significantly reduced locomotive activity and motor coordination. SLPE significantly protected against CYP-induced mechanical and thermal hyperalgesia. Furthermore, SLPE displayed robust antinociceptive effect by counteracting formalin and acetic acid induced hyper-nociception. In addition, SLPE increased the locomotive activity as well as the grip and motor coordination of the CYP treated rats. In conclusion, these results revealed the protective effects of SLPE against CYP-induced peripheral neuropathy and could be an effective therapeutic remedy for chemotherapy induced peripheral neuropathy.  相似文献   
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