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81.
Choi IY Kim SJ Jeong HJ Park SH Song YS Lee JH Kang TH Park JH Hwang GS Lee EJ Hong SH Kim HM Um JY 《Molecular and cellular biochemistry》2007,305(1-2):153-161
The citrus unshiu peel has been used traditionally as a medicine to improve bronchial and asthmatic conditions or cardiac
and blood circulation in Korea, China, and Japan. Here, we report the effects of citrus unshiu peel water extract (CPWE) on
the phorbol myristate acetate (PMA) + calcium ionophore A23187-induced hypoxia-inducible factor-1α (HIF-1α) activation and
inflammatory cytokine production from the human mast cell line, HMC-1 cells. We compared CPWE with hesperidin, a common constituent
of citrus unshiu. CPWE and hesperidin inhibited the PMA + A23187-induced HIF-1α expression and the subsequent production of
vascular endothelial growth factor (VEGF). In addition, CPWE suppressed PMA + A23187-induced phosphorylation of the extracellular
signal-regulated kinase (ERK). We also show that the increased cytokines interleukin (IL)-1β, IL-8, and tumor necrosis factor
(TNF)-α level was significantly inhibited by treatment of CPWE or hesperidin. In the present study, we report that CPWE and
hesperidin are inhibitors of HIF-1α and cytokines on the mast cell-mediated inflammatory responses. 相似文献
82.
83.
Vincent J. Tepedino Diane Gail Alston Brosi A. Bradley Trent R. Toler Terry L. Griswold 《Biodiversity and Conservation》2007,16(11):3083-3094
Capitol Reef National Park in central Utah, USA surrounds 22 managed fruit orchards started over a century ago by Mormon pioneers.
Honey bees are imported for pollination, although the area in which the Park is embedded has over 700 species of native bees,
many of which are potential orchard pollinators. We studied the visitation of native bees to apple, pear, apricot, and sweet
cherry over 2 years. Thirty species of bees visited the flowers but, except for pear flowers, most were uncommon compared
to honey bees. Evidence that honey bees prevented native bees from foraging on orchard crop flowers was equivocal: generally,
honey bee and native bee visitation rates to the flowers were not negatively correlated, nor were native bee visitation rates
positively correlated with distance of orchards from honey bee hives. Conversely, competition was tentatively suggested by
much larger numbers of honey bees than natives on the flowers of apples, apricots and cherry; and by the large increase of
native bees on pears, where honey bee numbers were low. At least one-third of the native bee species visiting the flowers
are potential pollinators, including cavity-nesting species such as Osmia lignaria propinqua, currently managed for small orchard pollination in the US, plus several fossorial species, including one rosaceous flower
specialist (Andrena milwaukiensis). We suggest that gradual withdrawal of honey bees from the Park would help conserve native bee populations without decreasing
orchard crop productivity, and would serve as a demonstration of the commercial value of native pollinators. 相似文献
84.
The Basidiomycotine fungi Meira geulakonigii, Meira argovae and Acaromyces ingoldii were assayed in the laboratory against five species of herbivorous mites: Phyllocoptruta oleivora (Eriophyidae), Panonychus
citri, Eutetranychus
orientalis, Tetranychus
urticae and Tetranychus
cinnabarinus (all four Tetranychidae). All fungi caused significantly high mortality rates (as compared to controls) after 14 days, some
after 1 week. Phyllocoptruta oleivora was the most susceptible, showing >80% mortality even after 1 week. In a field trial, grapefruits sprayed either once a month
or once a season with M. geulakonigii had significantly fewer P. oleivora and less damage than unsprayed fruit. These results suggest that M. geulakonigii may protect grapefruits against the injurious P. oleivora. 相似文献
85.
Hirsutella thompsonii Fisher is a host-specific fungal pathogen of the diverse group of arthropods known as the Acari. It particularly affects
eriophyid mites, and the identification of its isolates is a difficult task due to its pleomorphic nature. Seven isolates
of H. thompsonii var. thompsonii and H. thompsonii var. synnematosa collected from various agro-climatic regions of India were subjected to PCR analysis using random decamer primers to differentiate
between them. Random amplified polymorphic DNA analysis revealed that all of the isolates from the citrus rust mite, Phyllocoptruta oleivora Ashmead (Acari: Eriophyidae), clustered together, with the exception of one, HtCRMB. The only isolate of H. thompsonii from Aceria guerreronis keifer (Acari: Eriophydae), HtPDBC, clustered separately. 相似文献
86.
Sex pheromone of the cloaked pug moth,Eupithecia abietaria (Lepidoptera: Geometridae), a pest of spruce cones
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H. L. Wang G. P. Svensson J. Jakobsson E. V. Jirle O. Rosenberg W. Francke O. Anderbrant J. G. Millar C. Löfstedt 《Journal of Applied Entomology》2015,139(5):352-360
The sex pheromone of the cloaked pug moth, Eupithecia abietaria Götze, an important cone‐feeding pest in spruce seed orchards in Europe, was investigated. Chemical and electrophysiological analyses of pheromone gland extracts of female moths and analogous analyses of synthetic hydrocarbons and epoxides of chain length C19 and C21 revealed (3Z,6Z,9Z)‐3,6,9‐nonadecatriene (3Z,6Z,9Z‐19:H) and 3Z,6Z‐cis‐9,10‐epoxynonadecadiene (3Z,6Z‐cis‐9,10‐epoxy‐19:H) as candidate pheromone components, which were found in a gland extract in a ratio of 95 : 5. In field trapping experiments, conspecific males were only attracted to a combination of 3Z,6Z,9Z‐19:H and the (9S,10R)‐enantiomer of 3Z,6Z‐cis‐9,10‐epoxy‐19:H. The (9R,10S)‐enantiomer was not attractive, which is in agreement with studies on other Eupithecia species, for which males have only been attracted by the (9S,10R)‐enantiomer of epoxides. Subsequent experiments showed that E. abietaria males were attracted to a wide range of ratios of the two active compounds and that trap catches increased with increasing dose of the binary blend. A two‐component bait containing 300 μg 3Z,6Z,9Z‐19:H and 33 μg of the (9S,10R)‐enantiomer of 3Z,6Z‐cis‐9,10‐epoxy‐19:H was efficient for monitoring E. abietaria in spruce seed orchards in southern Sweden, where this species has probably been overlooked as an important pest in the past. With sex pheromones recently identified for two other moths that are major pests on spruce cones, the spruce seed moth, Cydia strobilella L., and the spruce coneworm, Dioryctria abietella Denis & Schiffermüller, pheromone‐based monitoring can now be achieved for the whole guild of cone‐feeding moths in European spruce seed orchards. 相似文献
87.
渭北旱塬苹果园地产量和深层土壤水分效应模拟 总被引:8,自引:0,他引:8
为了研究实时气象条件下渭北旱塬不同生长年限苹果园地产量变化趋势和深层土壤水分变化规律,在模型适用性与模拟精度验证基础上,应用WinEPIC模型模拟研究了1962—2001年期间洛川旱塬苹果园地产量演变动态和深层土壤水分效应。结果表明:(1) 在模拟研究期间,洛川旱塬4—40年生苹果园产量整体上呈波动性下降趋势,初期产量逐渐增加,11—23年生达到最大值(平均为28.8 t/hm2),之后随降水量年际波动呈现出明显的波动性降低趋势。(2) 40年间苹果园地遭受的干旱胁迫日数呈波动性上升趋势,与年降水量波动趋势相反。(3) 1—15年生期间苹果园地平均年耗水量高于同期年降水量,导致苹果园地0—10 m土层土壤强烈干燥化,逐月土壤有效含水量波动性降低,1—10年生、11—20年生和21—40年生期间发生土壤干燥化并且程度逐渐加剧,但干燥化速率逐渐减缓,土壤干燥化速率分别为95.4 mm/a、12 mm/a和1.5 mm/a。(4) 随生长年限的延长,苹果园地0—10 m土层土壤湿度逐渐降低、土壤干层分布深度逐渐加大,在14年生时超过了10 m,20年生以后2—10 m 土层形成稳定的土壤干层。因此,基于土壤水分利用的苹果生长与果园利用的合理年限为20 a,最长不宜超过23 a。 相似文献
88.
89.
In-field production of parasitoids of Dysaphis plantaginea by using the rowan aphid Dysaphis sorbi as substitute host 总被引:1,自引:0,他引:1
Emmanuel?BribosiaEmail author Dany?Bylemans Marc?Migon Georges?Van?Impe 《BioControl》2005,50(4):601-610
A system was developed to provide the parasitic wasp Ephedrus persicae Froggatt (Hymenoptera: Braconidae: Aphidiinae), which attacks the rosy apple aphid Dysaphis plantaginea (Passerini) (Homoptera: Aphididae), with the alternative host Dysaphis sorbi Kaltenbach (Homoptera: Aphididae) in apple orchards. Rowan trees (Sorbus aucuparia L.) arranged along the side of an unsprayed orchard were artificially infested in late February 2002 with eggs of D. sorbi. Colonies of D. sorbi successfully developed from the introduced eggs and persisted on several trees until the end of June. The only primary parasitoid species emerging from a sample of mummified aphids collected in spring from the infested rowan trees was the braconid wasp species E. persicae. In a host-switching experiment, nymphs of D. plantaginea proved suitable for female parasitoids originating from mummified D. sorbi. A series of mummies collected from the rowan trees in early summer contained diapausing parasitoids and hyperparasitoids that only hatched in April of the following spring. These observations suggest the possibility of establishing a local population of E. persicae in apple orchards, so that D. plantaginea can be readily attacked by diapause-emerging parasitoids in early spring. 相似文献
90.
Neng-Guo Tao Juan Xu Yun-Jiang Cheng Xiu-Xin Deng 《植物学报(英文版)》2006,48(3):315-319
A cDNA library was constructed end characterized from the pulp of Cera Care navel orange (Citrus sinensis Osbeck) at different stages of ripening. Tittering results revealed that approximately 5.086×10^5 independent clones were included in this library. Electrophoresls gel results of 15 randomly selected clones revealed that the size of the insertion fragments ranged from 400 bp to 2 kb, with an average size of 900 bp. Sequencing results of 150 randomly picked clones showed that the recombination rate was 94%. During subsequent sequence analysis, 41 of 139 clones failed to be identified end the amino sequence of 71 clones shared less than 30% identity with related plants in GenBank. Of 27 clones whose amino sequences shared more than 60% identity with other related plants in GenBenk, 17 clones showed an 80% identity with the corresponding candidate genes of citrus. The clone recognized as the type Ⅲ metallothlonein-llke (MT) gene was observed to occur 13 tlmes, Indlcatlng that the protein may play an important role In frult development and rlpenlng. 相似文献