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81.
This study compared endometrial cytology vis‐a‐vis uterine fluid cytology for assessment of uterine health in clinically normal and subclinical endometritis (SE)‐affected buffaloes. Uterine fluid samples and endometrial samples were collected from the buffaloes (n = 38) at oestrus using blue sheath and cytobrush, respectively. The smears were stained with Field stain for 3 minutes, and a minimum of 400 cells were counted in each smear for determination of the percentage of polymorphonuclear (PMN) leucocyte. The incidence of subclinical endometritis, based on the cytobrush cytology, was 23.08%. The correlation between cytobrush cytology with uterine fluid cytology was positive and significant (r = .37; p = .02). The ratio of PMN leucocyte in cytobrush cytology to uterine fluid cytology was 1:2.4. ROC analysis revealed that the threshold value of 6.16% PMN leucocyte in uterine fluid cytology showed a diagnostic sensitivity and specificity of 100% in differentiating normal from SE‐affected buffaloes. In conclusion, collection of uterine fluid was easier compared to collection of endometrial samples using cytobrush and the percentage of PMN leucocyte in uterine fluid cytology can be used as a tool for diagnosis of subclinical endometritis in buffaloes.  相似文献   
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An elongated sacral lamina has been described as one of the contributing factors for dogs with cauda equina syndrome due to degenerative lumbosacral stenosis (DLSS); however, published evidence is lacking on the accuracy of radiographic screening for the presence of this lesion. Objectives of this prospective, cross‐sectional cadaver study were to describe the accuracy and repeatability of detection of the cranial sacral lamina margin on plain lateral radiographs of the lumbosacral junction in dogs. Twenty‐five medium and large breed canine cadavers were radiographed before and after placement of a radiopaque hook in the cranial margin of the sacral lamina. Three independent evaluators placed digital markers at the perceived margin on preinterventional radiographs. The distance from perceived location to the true location on postinterventional radiographs was recorded for each dog and observer. A discordance threshold (distance between perceived and actual margin) of 1.5 mm was subjectively defined as clinically relevant. The three evaluators demonstrated good repeatability, although the accuracy for margin detection was only fair (mean discordance 1.7 mm). Evaluators demonstrated greater accuracy in identifying the landmark in juveniles (1.4 mm) vs. adults (1.8 mm; P < 0.01). Results of this study indicated that observer repeatability is good and accuracy is fair for correctly identifying the radiographic cranial margin of the sacral lamina in dogs. This should be taken into consideration when interpreting elongation of the sacral lamina in radiographs of dogs with suspected DLSS, especially adults.  相似文献   
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Oxisols are a product of long and intense weathering. Their actual characteristics can neither be traced back to a certain climatic period, nor do they reveal the present soil-forming factors. In this paper, therefore, a reconstruction of the soil genesis of a strongly weathered Oxisol is attempted by comparing the present mineralogical status and the recent dynamics of selected elements with a nearby Inceptisol from the same catena. The parent rock of both soils is serpentinized dunite with nepheline-syenitic veins; the soil moisture regime is udic. Chemical and mineralogical parameters, as well as the concentration of elements in the soil solution of a Typic Haploperox and an Oxic Dystrochrept from the same catena were analyzed for one year. The dynamics of Si and Mg strongly depended on the state of weathering. In the saprolite of the Dystrochrept, Si is partially removed and partially fixed by the formation of quartz and mixed layer minerals. Mg is first fixed in mixed layer minerals, but is during consecutive weathering leached from the transition zone from saprolite to the oxic horizon. Due to the high redox potential, Fe is not soluble, forming goethite in the upper part of the saprolite. Al is also not removed and is finally fixed in kaolinite. In the weathered upper part of both profiles the concentration of Al, Si, Mg and Fe in the soil solution is too low to perceive a further weathering. The present dynamics of Fe, Al, Mg and Si and the mineralogical status of the Dystrochrept indicate that these processes are similar to those that have led to the formation of the Haploperox. The soils, therefore, developed exclusively by the relative enrichment of Al and Fe, the partial loss of Si and the almost complete loss of Mg. Desilification and ‘laterisation’ are hence processes occurring also presently under a tropical rain forest climate.  相似文献   
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Soils are suggested to be an important factor influencing the vegetation pattern. In order to prove this hypothesis in an arid and sandy Negev ecosystem of longitudinal dunes and interdune corridors near Nizzana, Israel, the distribution of soil units and plant communities were compared on a very small-distance level. The Nizzana site has a size of nearly 100 ha. 250 soil pits with 3–5 horizons were mapped and sampled within the soil geographical monitoring. Soil water capacity and cation exchange capacity were estimated from the field data. In addition 176 plots of 100 m2 were established around the soil pits with emphasis on plants, coveting the environmental gradient across the dune ridges. Plant mapping plots were arranged into groups with the same dominating perennial species and a key for the vegetation mapping was developed. In the investigated desert site topography, soil surface crust, soil texture and salt content partly can explain the distribution of plant communities. A soil classification proposal is based on these parameters and is a useful tool to indicate correlations between soil units and the vegetation pattern. Nevertheless, dependent on topography and surface and/or subsurface water flow as well as the occurrence of “fertile islands” the moisture and nutrient regimes influence the vegetation pattern with respect to plant growth to a greater extent than the soils themselves.  相似文献   
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Salinity reduced (reduction below control = RBC) grain yield of rice by 80 and 98% at 8 and 16 mS/cm levels of saline irrigation, respectively, below tap water (0.6 mS/cm). The adverse effect of salinity was more pronounced on grain yield (98% RBC at 16 mS/cm) than on straw yield (84% RBC). The combined application of gypsum and Zn at the rates of 160 and 5 kg/ha produced 49, 45, and 41% more grain yield above controls at 0.6, 8, and 16 mS/cm levels of salinity, respectively. The length of panicles, percentage of filled grains, and 1000-grain weight, protein concentrations of the rice grains, sum of Ca, Mg and K concentrations were reduced due to imposition of saline irrigation, but gypsum and Zn treatments significantly improved these parameters even at the highest (16 mS/cm) salinity stress. The combined application of gypsum and Zn was found to be effective to increase the protein concentrations in rice grains by 2–4% and to increase total concentrations of Ca, Mg and K, but reduced the Na/K ratios in plant tissues by 29.13, and 12% at 0.6, 8, and 16 mS/cm salinity, respectively, suggesting that the application of gypsum and Zn in parallel with irrigation of saline soils, would be effective to reduce the adverse effects of high Na/K ratios as well as to improve growth, yield, and nutritional balance in rice.  相似文献   
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