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Two isolates of Botrytis cinerea and one of Colletotrichum coccodes were used to test for synergistic or antagonistic interactions (a) between pairs of 11 common fungicides and (b) between mixtures of individual fungicides with components of foliar fertilisers. Two screening assays monitored the effects with time of inhibitor combinations on spore germination and subsequent mycelial growth. The combinations that gave positive results for interaction in the screening assays were further investigated by a third quantitative assay, which compared the observed inhibition of mycelial growth with the net inhibition predicted by a non-interaction model. This model assumed that the components of a combination of substances each inhibited the test fungus independently of one another. Only mixtures of anilazine with zinc or copper resulted in appreciable deviation from the predicted behaviour based on a non-interaction model. The inhibition of mycelial growth by combinations of anilazine with Zn2+ (inorganic salt or formulated with urea) was consistently greater than predicted for each of three fungi on either of the two test media. Similar effects were observed with Cu2+, although the synergism was less marked. 相似文献
63.
KM Morton SP de Graaf A Campbell LM Tomkins WM Chis Maxwell G Evans 《Reproduction in domestic animals》2005,40(5):422-428
Ovum pick-up (OPU) was performed three times on adult ewes after synchronization with (n = 4) or without (n = 4) FSH treatment to investigate the effects of FSH treatment on the number of ovarian follicles, oocytes recovered, oocyte quality and development in vitro. FSH treatment increased the number of ovarian follicles (85 vs 162) and oocytes recovered (33 vs 91), although recovery rate was similar for ewes with and without FSH (91/162, 56.2% and 33/85, 38.8% respectively). Of the oocytes recovered, those classified as grades I and II were similar between ewes with (78/91, 85.7%) and without FSH treatment (27/33, 81.8%). The number of ovarian follicles was similar after repeated OPU for ewes treated with FSH, but for ewes not treated with FSH the number of ovarian follicles decreased with repeated OPU. The number of oocytes recovered decreased for FSH-treated ewes only, while the oocyte recovery rate and proportion of oocytes classified as grades I and II were not affected by repeated OPU. Oocyte cleavage (46/78, 58.9% and 19/24, 79.2%) and blastocyst formation (35/46, 76.1% and 12/19, 63.2% respectively) were similar for ewes with and without FSH treatment. The number of ovarian follicles varied between ewes (p < 0.05) although the number of oocytes recovered and oocyte development in vitro were similar between ewes. 相似文献
64.
RADIOGRAPHIC AND COMPUTED TOMOGRAPHIC DETERMINATION OF FEMORAL VARUS AND TORSION IN THE DOG 总被引:1,自引:0,他引:1
ROBERT M. DUDLEY MICHAEL P. KOWALESKI WM TOD DROST JONATHAN DYCE 《Veterinary radiology & ultrasound》2006,47(6):546-552
Diagnosis and quantification of femoral varus and femoral torsion using radiographs is technically challenging due to the difficulty in determining proper positioning. The purpose of this study is to describe a computed tomographic technique for determination of femoral varus and femoral torsion and to compare this technique, and standard radiography, to anatomic preparation, for the measurement of femoral varus and femoral torsion in normal dogs. Nine canine cadavers, visually and radiographically free of orthopedic disease of the hip and stifle joints, were utilized for analysis. Femoral varus was determined using a craniocaudal radiograph, a craniocaudal radiograph obtained after confirming accurate positioning using horizontal beam fluoroscopy, and computed tomography (CT). Femoral torsion (expressed as angle of version) was determined using an axial radiographic projection obtained from distal to proximal and CT. Each femur was dissected free of soft tissues, and direct determination of femoral varus and femoral torsion was performed using digital photographic images. All radiologic and photographic images were digitally measured to quantify the magnitude of femoral varus and femoral torsion. For femoral varus, no difference ( P =0.149) between the three different imaging techniques and the anatomic preparation was identified. For femoral torsion, no difference ( P =0.059) between the two imaging techniques and the anatomic preparation was identified. Well positioned radiographs and the described computed tomographic method are both as accurate as anatomic preparation for the measurement of both femoral varus and femoral torsion in normal dogs. 相似文献
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The soil porespace was studied in two long-term tillage experiments on two clayey stagnogleys in Southern England. The soils differed in respect of mineral and organic composition and previous management history. In both soils the total volume of pores and the volume fraction of macropores in the topsoil horizon declined with direct drilling compared with annual ploughing. This difference between tillage treatments appeared to develop more slowly in the soil that was formerly under continuous arable cultivation than in the soil that was previously in long-term grassland. Fluid transport coefficients were greater in ploughed topsoil in both soils; however, at the boundaries between topsoil and subsoil, and in the upper subsoil, permeability and gaseous diffusivity were greater after direct drilling. At a long-term arable site, soil was more consolidated below the depth of ploughing or shallow tillage, whereas in a former grassland soil ploughing disrupted the continuity of channel-type macropores. 相似文献
67.
A study using Cs-134 tagged sediment suspended in infiltrating water has indicated that clay can move in calcareous materials. The study indicated that the time and conditions under which clay movement is initiated in calcareous materials are functions of the availability of clay for movement, channels or pores for the clay to move through, and the quantity of precipitation available to move the clay. 相似文献
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