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321.
Two pea (Pisum sativum L.) cultivars were compared: cv Lincoln and cv Douce de Provence. Seedlings grown for 14 d on standard medium were challenged for 21 d with salt using a split-root system. This protocol allowed salt-treated plants to absorb nutrients through a part of their root system maintained in control medium (C), the other part of the root system being placed in medium added with 75 mM NaCl (S). Full salt treatment (S/S) resulted in severe but non-lethal growth inhibition, high concentration of Na+ and Cl− in leaves, and decrease in leaf K+ and chlorophyll contents. The two latter effects were more pronounced in Lincoln than in D. Provence. Growth inhibition was partially (Lincoln) or totally (D. Provence) alleviated in S/C configuration, and K+ content was less diminished than in full salt treatment. S/C treatment mitigated Na+ and Cl− accumulation in Lincoln, but not in D. Provence. Thus, in the latter cultivar, growth inhibition by salt in S/S condition likely did not result from excessive Na+ and Cl− accumulation in leaves. Increased electrolyte leakage from leaf tissues evidenced damages to leaf cell plasma membrane of both cultivars in S/S condition. However, damages to chloroplasts, as inferred from chlorophyll loss, were much pronounced in Lincoln than in D. Provence. Antioxidant enzymic activities in leaves were measured as proxies for oxidative stress. Catalase activity was stimulated by S/S treatment in both cultivars, but superoxide dismutase (Fe and Cu/Zn isoforms) and gaiacol peroxidase activities were augmented only in Lincoln. The absence of superoxide dismutase activity stimulation by salt in D. Provence could signify either that constitutive activity was sufficient to ensure protection against oxidative stress, or that intrinsic salt tolerance of this cultivar mitigated cellular oxidative stress. Thus, intraspecific variability for salt response exists between pea cultivars presenting similar growth sensitivity to salt. 相似文献
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Jrme Cortet Annette Gomot-De Vauflery Nicole Poinsot-Balaguer Lucien Gomot Christine Texier Daniel Cluzeau 《European Journal of Soil Biology》1999,35(3):115
A critical review of biological parameters used to indicate pollutant impact on soil quality was conducted. These parameters mention some soil invertebrates. The value of an indicative organism depends on its life expectancy, life style and specific importance. Nematodes, mites, collembolans, enchytraeids, earthworms, isopods and molluscs are good potential biological indicators. Biological indicators of bioaccumulation and biological indicators of effects (toxicological and ecological) can be distinguished. Bioaccumulation studies are difficult to interpret, as wide variations could be found, depending on taxonomic group, habitat, organ studied, soil type or even pollutant type. Some groups, such as Collembola, require in depth bioaccumulation studies. It is suggested to use a pool of macro-concentrators, including at least some earthworm, isopod and gastropod species. Toxicological indicators have been well studied and their lethal and sublethal pollutant effects are well known. However, studies have focused on only a few species, such as the earthworm Eisenia foetida or the collembolan Folsomia candida. These studies should be extended to other zoological groups, as well as to several species from the same group, to generate a representative test battery. Exposure biomarkers and physiological change studies should be emphasised, as they act as very early warning systems of contamination. Data are currently lacking on how soil biological processes malfunction due to pollution. We need to explore the links between pollutant effects on soil fauna and pollutant effects on soil functioning. Concerning ecological indicators, studies should develop sampling techniques and parameters, which are specific to ecotoxicological goals. Before-after impact control procedures should be carried out, to eliminate the background noise of the study site and only evaluate the influence of pollutants. On the other hand, ecological indices, such as taxonomic diversity or richness, should be used carefully especially concerning chronic pollution. Effects of pollutants on biological cycle studies seem very promising, but need further information on the life history strategies of many species. Furthermore, the pollutant tolerance of rare species should be considered. The different types of biological indicators yield complementary information on pollutant effects. They all need standard procedures. In this context, studies should be extended and diversified, and associate bioaccumulation, toxicological and ecological indicators to provide better information on soil quality.
Résumé
Une liste critique des paramètres biologiques utilisés dans certains travaux pour indiquer l'impact des polluants sur la qualité des sols a été établie. Ces paramètres font référence à un ou plusieurs invertébrés du sol. Le rôle d'organisme indicateur dépend de leurs caractéristiques biodémographiques, de leur mode de vie, de leur taille spécifique. Les nématodes, acariens, collemboles, enchytréides, vers de terre, isopodes et gastéropodes sont potentiellement des indicateurs biologiques. Indicateurs biologiques de bioaccumulation et indicateurs biologiques d'effets (toxicologiques et écologiques) peuvent être distingués. Les études de bioaccumulation sont difficiles à interpréter, car de fortes variations sont observées. Ces variations dépendent du groupe taxonomique étudié, de l'habitat, de l'organe étudié, du type de sol ou bien encore du type de pollution. Certains groupes, comme les collemboles demandent des études plus poussées à ce sujet. Il est suggéré d'utiliser un pool de macro-concentrateurs, avec au moins des espèces de vers de terres, isopodes et gastéropodes. Concernant les indicateurs toxicologiques d'effets, les études les plus nombreuses concernent les effets létaux et sublétaux. Toutefois ces études concernent peu de groupes taxonomiques (essentiellement le vers Eisenia foetida et le collembole Folsomia candida), et devraient être étendues à d'autres groupes zoologiques, ainsi qu'à différentes espèces du même groupe, afin de créer une batterie de tests représentatifs. Les travaux concernant les biomarqueurs et les changements physiologiques devraient être amplifiés, car ils permettent d'obtenir des systèmes d'alarme très précoces concernant l'impact des contaminants. Un manque persistant de données concerne les conséquences de pollutions sur le fonctionnement des écosystèmcs. Il est en effet important désormais d'explorer les liens entre les effets des polluants sur la faune du sol et les effets réels de ces mêmes polluants sur le fonctionnement des sols. Concernant les indicateurs écologiques, les travaux entrepris devraient développer des méthodes d'échantillonnage et des paramètres spécifiques au domaine écotoxicologique. Ainsi, il est préconisé d'entreprendre des études combinant les approches synchroniques et diachroniques. afin d'éliminer le bruit de fond induit par le site d'étude et évaluer uniquement l'influence du polluant. En outre, les indices écologiques, comme la diversité ou la richesse taxonomique, doivent être utilisés avec précautions, particulièrement lors des études de pollution chronique. Par ailleurs, les études concernant les effets de polluants sur les cycles biologiques semblent prometteuses, mais demandent de meilleures connaissances concernant les stratégies de vies des différentes espèces étudiées. De plus, la tolérance aux pollutions des espèces rares devrait être fortement prise en considération. Les différents types d'indicateurs biologiques fournissent des informations complémentaires. Ils demandent tous une standardisation des protocoles. Dans ce contexte, les études devraient être développées et diversifiées et associer les indicateurs de bioaccumulation avec les indicateurs biologiques d'effets pour améliorer l'information sur la qualité des sols. 相似文献324.
Kang Liu Beiping Tan Wei Zhang Hongyu Liu Xiaohui Dong Qihui Yang Shuyan Chi Shuang Zhang Haitao Zhang 《Aquaculture Research》2019,50(8):2155-2169
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利用2005年10月至2006年1月印度洋公海撒雅德玛哈浅滩(Saya de Malha Bank)丝尾红钻鱼(Etelis coruscans)延绳钓渔获物生物学测定数据,应用统计及回归方法分别对310尾丝尾红钻鱼的性腺成熟度、性别比例、叉长分布、叉长与体质量(GW)的关系等进行了研究.结果表明(1)雄性个体所占比例高于雌性个体,雌性与雄性个体的性别比例为12.39;(2)丝尾红钻鱼性腺成熟度以Ⅴ、Ⅵ级为主,Ⅴ级比例最高,占60.80%,其中分性别统计,雌性、雄性丝尾红钻鱼的性腺成熟度皆为Ⅴ级比例最高,分别为52.27%和65.24%,雌性丝尾红钻鱼中性腺成熟度Ⅵ级个体比例(30.68%)远高于雄性样本中性腺成熟度Ⅵ级个体比例(5.71%);(3)叉长分布基本上符合正态分布,优势叉长为683~803 mm,平均叉长为747 mm,在同一性腺成熟度时,雌性丝尾红钻鱼的平均叉长略大于雄性丝尾红钻鱼的平均叉长;(4)根据幂函数回归所得叉长(FL)与体质量(W)的关系式为W=9.439 0×10 6FL3 0817,其生长指数b值略大于太平洋海域丝尾红钻鱼种群的生长指数b值;(5)雌雄个体叉长与体质量关系式比较发现,在叉长小于897mm时,雄性个体的体质量大于雌性个体体质量.在叉长大于897mm时,则雌性个体体质量大于雄性个体体质量. 相似文献
327.
The aim of this research was to show the interest of an original technique of microanalysis : the laser probe mass spectrograph (L.P.M.S.), to study the variations of the mineral content in transverse sections of woody stems. In this technique a mass spectrometer analyses the ions liberated during the bombardment of the sample by a laser beam. It allows analysis in different points of the surface and in depth with a diameter of the beam of 50 to 100 μm. The detection limits may be increased by accumulation of spectra from repetitive shots at the same point. Samples (5 to 10 mm diameter, 1 to 2 mm thickness) cut on young stems of walnut tree (Juglans regia) were analysed after freeze drying, then observed in scanning electron microscopy to correlate the position of the laser craters with the analytical data. The preliminary results presented give a qualitative information about the variations of the relative content of the following elements : C, O, N, P, K, Ca, Mg, S simultaneously detected along diametral lines on the analysed sections. 相似文献
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329.
Objectives To document the clinical manifestations, development, progression, and mode of inheritance of the retinopathy of Coton de Tulear dogs.
Materials and methods Multiple Coton de Tulear dogs were examined with biomicroscopy, indirect ophthalmoscopy, photopic and scotopic electroretinography, fluorescein and indocyanine green angiography, optical coherence tomography, ultrasonography, and fundic photography for 3 years.
Results The retinopathy of Coton de Tulear dogs is inherited as an autosomal recessive condition and manifests as multifocal serous retinal detachments in homozygous puppies, between 3 and 4 months of age. Optic coherence tomography and ultrasonography confirm multiple focal serous retinal detachments. Serial fundic photographs confirmed minimal progression of lesions beyond 1 year of age. Electroretinography identified diminished scotopic and photopic amplitudes; however, the only significant differences between affected and age-matched control Coton de Tulear dogs were noted during photopic flicker electroretinograms. Leakage of fluorescein or indocyanine green through the blood ocular barriers was not detected during repeated angiograms prior to, during, and after development of the retinopathy. There was no focal pooling of fluorescein in any of the dogs examined. Focal retinal thinning was detected with optical coherence tomography over each detachment and the serous content of some of the bullae diminish after several years leaving focal areas of hyper-reflectivity.
Conclusions Multifocal retinopathy of Coton de Tulear dogs is inherited as an autosomal recessive condition. The retinopathy manifests early in life as nonprogressive multifocal bullous retinal detachments. The blood ocular barrier remains intact. Photopic and scotopic electroretinography are minimally diminished compared to age-matched dogs. 相似文献
Materials and methods Multiple Coton de Tulear dogs were examined with biomicroscopy, indirect ophthalmoscopy, photopic and scotopic electroretinography, fluorescein and indocyanine green angiography, optical coherence tomography, ultrasonography, and fundic photography for 3 years.
Results The retinopathy of Coton de Tulear dogs is inherited as an autosomal recessive condition and manifests as multifocal serous retinal detachments in homozygous puppies, between 3 and 4 months of age. Optic coherence tomography and ultrasonography confirm multiple focal serous retinal detachments. Serial fundic photographs confirmed minimal progression of lesions beyond 1 year of age. Electroretinography identified diminished scotopic and photopic amplitudes; however, the only significant differences between affected and age-matched control Coton de Tulear dogs were noted during photopic flicker electroretinograms. Leakage of fluorescein or indocyanine green through the blood ocular barriers was not detected during repeated angiograms prior to, during, and after development of the retinopathy. There was no focal pooling of fluorescein in any of the dogs examined. Focal retinal thinning was detected with optical coherence tomography over each detachment and the serous content of some of the bullae diminish after several years leaving focal areas of hyper-reflectivity.
Conclusions Multifocal retinopathy of Coton de Tulear dogs is inherited as an autosomal recessive condition. The retinopathy manifests early in life as nonprogressive multifocal bullous retinal detachments. The blood ocular barrier remains intact. Photopic and scotopic electroretinography are minimally diminished compared to age-matched dogs. 相似文献
330.