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71.
This paper describes a Viticulture Service-Oriented Framework (VSOF) which turns around context elements or tags that are placed in the field and which can be decoded by mobile devices such as mobile phones or PDAs. The tags are used to automatically associate a field location to the relevant database tables or records and also to access contextual information or services. By pointing a mobile device to a tag, the viticulturalist may download data such as climatic data or upload information such as disease and pest incidence in a simple way, without having to provide coordinates or any other references, and without having to return to a central office. This work is part of an effort to implement a large-scale distributed cooperative network in the Douro Demarcated Region in Northeast Portugal, a region in which the effort makes particular sense due to the extremely variable topography and mesoclimates. The possibility of exchanging contextualized information and accessing contextualized services in the field, using well-known devices such as cell phones, may contribute to increase the rate of adoption of information technology in viticulture, and contribute to more efficient and closer-to-the-crops practices.  相似文献   
72.
The presence of the zona pellucida has been perceived as a requirement for the oviductal transfer of cloned embryos at early stages of development while protecting the embryo from an immune system response. We hypothesized that steroid hormone therapy could reduce a potential cellular immune response after the transfer of zona‐free cloned embryos into the oviduct of recipient female goats. In Experiment 1, seven does were used to study the systemic immunosuppressant effect of the methylprednisolone administration (for 3 days) on blood cell counts. Whole blood was collected prior to treatment with methyprednisolone and then on Days 1, 2, 3, 4, 7, 14, 21 and 28 after the first dose of methylprednisolone for the analysis of haematological parameters. Methylprednisolone treatment significantly reduced circulating white blood cells and neutrophils in comparison with pre‐treatment levels, demonstrating a systemic immunosuppressant effect. In Experiment 2, a group of 58 does were used as recipient females to study the effect of administration of methylprednisolone for 3 days on the establishment of pregnancies after the transfer of zona‐free cloned embryos into the oviducts. No effects on pregnancy rates on Day 30 were observed regarding the distinct treatment groups (control vs. methylprednisolone), the source of oocytes (in vivo‐ vs in vitro‐matured) or the presence or absence of the zona pellucida in embryos. In summary, methylprednisolone was effective at inducing a systemic immunosuppressed state in goats, but the treatment prior to embryo transfer did not affect pregnancy rates. Moreover, pregnancy rates were similar between zona‐free and zona‐intact goat cloned embryos.  相似文献   
73.
ABSTRACT

Humic (HA) and fulvic (FA) acids improve the nutrient availability and uptake by plants but some aspects of their agronomic use still need to be clarified. The effects of HA soil application and FA foliar application on the growth, Zn and B uptake by coffee seedlings were evaluated. HA was added to an Oxisol at concentrations 0, 10, 25, 50, 75 and 100 mg kg?1 (C-HA), in both limed (pH 6.2) and overlimed (pH 7.2) conditions. FA (0, 0.2, 0.5 and 1 g L?1 C-FA) was applied to coffee leaves in three different application modes (M): with 0.3% Zn and 0.6% B supplied via foliar (M1), 0.6% B and 1.2% Zn supplied via foliar (M2) and 1.2 mg kg?1 B and 6 mg kg?1 Zn supplied via soil (M3). HA addition in soil significantly (p < 0.05) reduced leaf B and Zn accumulation and coffee growth in both pH conditions. In the M1 and M2, FA application significantly (p < 0.05) increased the shoot growth at 0.59 and 0.45 g L?1 and B accumulation at 0.96 and 0.45 g L?1 C-FA. Foliar application of C-FA, instead soil application of C-HA, is a suitable practice to improve coffee seedlings growth and nutrition on Oxisol.  相似文献   
74.
Eddy  Behrens  MV  Jim  Schumacher  DVM  MS  Earl  Morris  DVM  MS  Mike  Shively  DVM  MS  PhD 《Veterinary radiology & ultrasound》1991,32(3):98-104
Contrast paranasal sinusography was a simple procedure that enhanced evaluation of the paranasal sinuses in the standing horse. Two techniques of positive-contrast paranasal sinusography were developed using cadavers and sedated horses. For both techniques, 37% organically bound iodine was used. For the first technique, the conchofrontal sinus was injected with 30 ml of contrast medium followed by an additional 100 ml and 70 ml. For the second technique, the rostral maxillary sinus was injected with 20 ml followed by an additional 50 ml. Each technique enhanced visualization of different paranasal sinuses, and each was necessary for complete positive-contrast radiographic evaluation of the paranasal sinuses. The techniques of positive-contrast radiographic evaluation of the paranasal sinuses are described.  相似文献   
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The aim of this study was to evaluate the histological alterations in the digestive and renal systems of 35 male ovines in Paraíba, Brazil, at around 16?± 1.87 kg submitted to the following treatments for 90 days (15 of adaptation +?75 of experimental period): 1- Tifton hay (TH); 2- Cassava foliage hay (CH); 3–35% TH and 35% CH; 4–35% TH and 35% forage palm (FP), and 5–35% CH and 35% FP, based on dry matter (DM). Samples of the liver, kidney, rumen, and small intestine were histomorphometrically evaluated and the data were submitted to ANOVA analysis and Tukey post test at p ≤?0.05. The use of alternative foods in the voluminous fraction (CH?+?FP) in the ovine diets did not compromise the performance of the animals; on the contrary, promoted better gain when compared with TH treatment (18.55 kg vs 9.42 kg). The CH?+?FP diet had a positive effect on papilla height. The papilla width decreased with the diets CH?+?FP and TH?+?FP. The thickness of the ruminal muscular layer were higher in the diets containing TH?+?CH and CH?+?FP. The keratinized layer of the ruminal epithelium was larger in the diet containing CH and FP. The villi of the intestinal crypts were deeper in the diets with FP and the villus/crypt ratio was the same in all diets. Goblet cells decreased with the CH or FP diet. Some renal changes were observed according to the diets, mainly when using FP. It is recommended to use CH and FP as a large fraction of the ovines diet, which will not alter animal performance.

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79.
The beneficial effect of corn seed treatment with zinc (Zn) is directly related to the source used. The excess of this micronutrient causes seedling stress and reduces growth. Thus, assuming that the use of exogenous phytohormones can minimize such effects, we evaluated different doses and sources of Zn for the treatment of maize seeds with or without salicylic acid. The experiment took place in the laboratory, and two factorial experiments, 2 × 4 + 1, were performed in a randomized design. The seeds were treated with either ZnO or ZnSO4 at doses of 0.5, 1, 2, and 3 g.kg?1 seed with four replications, differing only by the addition of 4.14 mg L?1 salicylic acid. Treating seeds with Zn and salicylic acid did not affect germination. ZnO led to a greater increase in dry mass in corn seedlings as compared with zinc sulfate, especially at higher doses (2 and 3 g kg?1 seed). Seed treatment with sulfate reduces root and shoot length, and salicylic acid did not attenuate this toxic effect. Dry mass is not affected when oxide is used. Salicylic acid reduces the accumulation of zinc in the treatment of corn seeds, regardless of the source used.  相似文献   
80.
The development of a DNA microarray method on a digital versatile disk (DVD) is described for the simultaneous detection of traces of hazelnut ( Corylus avellana L.), peanut ( Arachis hypogaea ), and soybean ( Glycine max ) in foods. After DNA extraction, multiplex PCR was set up using 5'-labeled specific primers for Cor a 1, Ar h 2, and Le genes, respectively. Digoxin-labeled PCR products were detected by hybridization with 5'-biotinylated probes immobilized on a streptavidin-modified DVD surface. The reaction product attenuates the signal intensity of the laser that reached the DVD drive used as detector, correlating well with the amount of amplified sequence. Analytical performances showed a detection limit of 1 μg/g and good assay reproducibility (RSD 8%), suitable for the simultaneous detection of the three targeted allergens. The developed methodology was tested with several commercially available foodstuffs, demonstrating its applicability. The results were in good agreement, in terms of sensitivity and reproducibility, with those obtained with ELISA, PCR-gel agarose electrophoresis, and RT-PCR.  相似文献   
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