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31.
H. Ulrich 《Journal of pest science》1968,41(7):101-106
Zusammenfassung Die Wirkung von 12 im Obstbau gebräuchlichen Fungiziden in praxisüblichen Anwendungskonzentrationen aufTrichogramma-Imagines wurde in Laborversuchen geprüft.Alle berücksichtigten Mehltau-Bekämpfungsmittel, Binapacryl, Dinocap, Triamphos und Chinomethionat, erwiesen sich als mehr oder weniger toxisch, desgleichen die Schorf-Bekämpfungsmittel Mancozeb, Dichlofluanid, Metiram und TMTD. Für die Schorf-Bekämpfungsmittel Captan, Dithianon, Dodin und Zineb wurde unter den Versuchsbedingungen keine Giftwirkung nachgewiesen.Die Angaben der Literatur über die Wirkung der genannten Fungizide aufTrichogramma und andere Chalcidoidea werden diskutiert.
Durchgeführt mit Unterstützung der Deutschen Forschungsgemeinschaft.
Dem Direktor des Instituts, Herrn Professor Dr. J. M. Franz, danke ich für sein reges Interesse an den Versuchen und die mir jederzeit gewährte Unterstützung. 相似文献
Summary The effects uponTrichogramma adults of 12 fungicides which are commonly in use in orchards, in normal concentrations were examined by laboratory trials.The mildew fungicides, binapacryl, dinocap, triamphos, and oxythioquinox proved to be toxic as well as the apple scab fungicides mancozeb (= coordination product of zinc ion and [ethylenebis(dithiocarbamato)] manganese), dichlofluanid, metiram (= zinc-activated polyethylene thiuram disulfide), and thiram. Under the conditions of the experiments, there was no evidence of a toxic effect exerted by the apple scab fungicides captan, dithianon, dodine, and zineb.The available data from literature on the effects of the fungicides mentioned uponTrichogramma and other chalcidoids are discussed.
Durchgeführt mit Unterstützung der Deutschen Forschungsgemeinschaft.
Dem Direktor des Instituts, Herrn Professor Dr. J. M. Franz, danke ich für sein reges Interesse an den Versuchen und die mir jederzeit gewährte Unterstützung. 相似文献
32.
33.
B. Ulrich 《European Journal of Forest Research》1977,96(1):366-367
34.
35.
Müller Ulrich Ringhofer Andreas Brandner Reinhard Schickhofer Gerhard 《Wood Science and Technology》2015,49(6):1123-1136
Wood Science and Technology - Several studies have dealt with the problem of how to measure the shear modulus of small clear wood specimens, avoiding bias from normal compression, bending, tension... 相似文献
36.
ABSTRACT Three carboxylic acid amide (CAA) fungicides, mandipropamid (MPD), dimethomorph (DMM) and iprovalicarb (IPRO) were examined for their effects on various asexual developmental stages of Phytophthora infestans in vitro and in planta. Germination of cystospores and direct germination of sporangia were inhibited with nanomole concentrations of MPD (0.005 mug/ml) and micromole concentrations of DMM (0.05 mug/ml) or IPRO (0.5 mug/ml). A temporary exposure of 1 h to CAAs was not detrimental to germination and infectivity of sporangia or cystospores. CAAs applied to cystospores at 1 h after the onset of germination did not prevent the emergence of germ tubes, but inhibited their further growth and deformed their shape. None of the fungicides affected discharge of zoospores from sporangia or the encystment (cell wall formation/assembly) of the zoospores. Mycelium growth in solid or liquid media was inhibited with micromole concentrations. CAAs mixed with sporangia and drop inoculated onto detached leaves strongly suppressed infection. Curative application at 1 day postinoculation (dpi) required higher concentrations of CAAs than preventive application to inhibit infection and lost its effectiveness at 2 dpi. When sprayed on established late blight lesions 4 days after inoculation, CAAs reduced sporangial production in a dose-dependent manner. Trans-laminar protection of potato or tomato leaves, although achieved with higher doses, was more effective with MPD than with DMM or IPRO. Shade house studies demonstrated superior control of late blight epidemics by MPD compared with the other molecules. The data suggest that germ tube formation by cystospores or sporangia is the most sensitive stage in the life cycle of P. infestans to CAAs. Of the three CAAs, MPD had the highest intrinsic activity against spore germination. This property, together with its better trans-laminar activity, makes MPD more effective than DMM or IPRO in controlling epidemics caused by P. infestans. 相似文献
37.
Marcel Suchowski Michael Eschbaumer Jens P. Teifke Reiner Ulrich 《Journal of veterinary diagnostic investigation》2021,33(5):997
Foot-and-mouth disease (FMD) is a highly contagious aphthoviral infection of cloven-hoofed animals, inducing vesiculopustular stomatitis, pododermatitis, and thelitis. Vesicular fluid represents a major pathway of virus excretion, but bovine milk is another important source of virus shedding. We describe here the time course of FMD virus (FMDV) excretion in the milk and characterize associated lesions in the mammary gland. Three dairy cows were infected by nasopharyngeal instillation of FMDV and monitored over 12 d. Autopsy was performed at the end of the study, and specimens were collected for histopathology, IHC, and RT-qPCR. All 3 cows developed fever, drooling, vesiculopustular stomatitis, interdigital dermatitis, and thelitis. FMDV RNA was detectable in whole milk until the end of the trial, but only transiently in saliva, nasal secretions, and blood serum. Although histology confirmed vesiculopustular lesions in the oral and epidermal specimens, the mammary glands did not have unequivocal evidence of FMDV-induced inflammation. FMDV antigen was detectable in skin and oral mucosa, but not in the mammary gland, and FMDV RNA was detectable in 9 of 29 samples of squamous epithelia but only in 1 of 12 samples of mammary gland. 相似文献
38.
E. J. T. Finding T. Ciasca M. J. Pinilla C. J. Driver I. C. Johns R. Weller H. A. Volk 《Equine Veterinary Education》2014,26(6):303-305
This report describes the diagnostic approach to, and treatment of, a case of severe pelvic limb ataxia in a Miniature Shetland pony. Diagnosis of an intradural‐extramedullary lesion at the level of T11–12 was made using CT myelography. Dorsolateral hemilaminectomy allowed surgical debulking of an intradural mass, diagnosed histopathologically as T cell rich B cell lymphoma. Post operative treatment with prednisolone, cytarabine and cyclophosphamide was tolerated well and the degree of ataxia reduced markedly, allowing the pony to return to normal management. 相似文献
39.
I. C. Johns E. J. T. Finding T. Ciasca K. Erles K. Smith R. Weller 《Equine Veterinary Education》2014,26(6):294-298
This case report describes an unusual diagnosis of central nervous system botryomycosis in a horse. A 16‐year‐old Welsh Section D gelding was evaluated for acute onset of hypermetric ataxia, leaning to the left and head tilt to the right. Based on the neurological signs, a cerebellar lesion with accompanying vestibular disease was suspected and supportive therapy consisting of antimicrobial and glucocorticosteroid drugs and hypertonic saline was instituted. This resulted in marked clinical improvement over a 48 h period. Computed tomography performed in the standing, sedated horse following initial stabilisation identified extensive sclerosis and lysis of the right temporal and occipital bones, consistent with an infectious or neoplastic process. Based on the grave prognosis for survival despite the clinical improvement, euthanasia was undertaken. Post mortem magnetic resonance imaging identified a mass lesion impinging on the right cerebellar hemisphere, sclerosis of the temporal and occipital bones lateral and ventral to the mass, as well as destruction of the temporal bone between the inner ear and the cerebellum. These changes corresponded to the presence of a mass within the right dorsal temporal bone, extending into the right lateral temporal bone. The mass extended to compress and adhere to the right lateral hemisphere of the cerebellum. A histopathological diagnosis of botryomycosis was made, affecting the temporal and occipital bones and compressing the cerebellum. 相似文献
40.
The global spread of the Asian tiger mosquito Aedes albopictus, an urban pest as well as a vector for arboviruses, is a threat for public health. As control measures include the use of insecticides such as the pyrethroid λ-cyhalothrin, it is crucial to assess their efficiency and their potential impact on the biodiversity especially under climate change conditions. To evaluate the environmental risk, biotests are well established for non-target organisms but not yet for mosquitoes. We therefore developed a full-lifecycle biotest for mosquitoes kept under quarantine conditions based on the OECD guideline 219. Therewith we tested the effect of temperature and nutrition on the ecotoxicological response to λ-cyhalothrin on the mosquitoes Ae. albopictus and Culex pipiens by assessing sublethal and life history parameters. The efficiency of λ-cyhalothrin decreased in both mosquito species with increasing temperature and changed with feeding protocol. At effective concentrations for potential mosquito control in surface waters, λ-cyhalothrin poses a high risk for indigenous aquatic key role species inhabiting the same microhabitats. Those aspects should to be taken into account in vector control strategies. 相似文献