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Efficacy of Gamithromycin for the Treatment of Foals with Mild to Moderate Bronchopneumonia 下载免费PDF全文
F. Hildebrand M. Venner S. Giguère 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2015,29(1):333-338
Background
Gamithromycin is active in vitro against the bacterial agents most commonly associated with bronchopneumonia in older foals. However, the clinical efficacy and safety of this drug have not been investigated.Hypothesis
Gamithromycin is effective for the treatment of bronchopneumonia in foals.Animals
One hundred and twenty‐one foals on a farm endemic for infections caused by Rhodococcus equi.Methods
In a controlled, randomized, and double blinded clinical trial, foals with ultrasonographic evidence of pulmonary abscesses (abscess score 8.0–20 cm) were randomly allocated in 3 treatment groups: (1) gamithromycin IM q7 days (n = 40); (2) azithromycin with rifampin, PO q24h (n = 40); or (3) no antimicrobial treatment (controls; n = 41). Physical examination and thoracic ultrasonography were performed by individuals unaware of treatment group assignment. Foals that worsened were removed from the study.Results
The proportion of foals that recovered without the need to be removed from the study was significantly higher for foals treated with gamithromycin (38 of 40) or azithromycin with rifampin (39 of 40) than for controls (32 of 41). Treatment with gamithromycin or with azithromycin‐rifampin resulted in a significantly faster decrease in the clinical score and abscess score compared to the controls. Adverse reactions characterized by colic (n = 18) and hind limb lameness (n = 14) were observed only in foals treated with gamithromycin.Conclusion and Clinical Importance
Gamithromycin was noninferior to azithromycin with rifampin for the treatment of bronchopneumonia in the study population but had a higher frequency of adverse reactions. 相似文献94.
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Paul E Verweij Gert HJ Kema Bas Zwaan Willem JG Melchers 《Pest management science》2013,69(2):165-170
Azole resistance is an emerging problem in the opportunistic mould Aspergillus fumigatus. The triazoles are the most important agents for the management of Aspergillus diseases in humans. Selection for acquired resistance may occur in the hospital setting through exposure to high doses of azoles during azole therapy, but evidence is accumulating that A. fumigatus may become resistant to medical triazoles through environmental exposure to fungicides. The recovery of A. fumigatus isolates resistant to the medical triazoles from azole‐naive patients as well as from the environment strongly indicates an environmental route of resistance selection. Molecule alignment studies have identified five fungicides that share a very similar molecule structure with the medical triazoles, and thus may have selected for mechanisms that confer resistance to both groups of compounds. It is important to explore further the presumed fungicide‐driven route of resistance selection in order to implement effective preventive measures as the prevalence of azole resistance in A. fumigatus continues to increase and causes major challenges in the management of azole‐resistant Aspergillus diseases. Copyright © 2012 Society of Chemical Industry 相似文献
96.
Evidence of anisotropy is reported for advective air and water permeabilities in soils. Thus, anisotropy is likely to exist also for diffusive gas fluxes. Information about direction‐dependent soil gas diffusivity is scarce and most modeling approaches assume isotropy. At hundreds of closely lying positions in a compacted and adjacent undisturbed forest soil, gas diffusivity (Ds/D0) was measured either in vertical or horizontal direction. The volume‐independent diffusion efficiency (i.e., diffusivity divided by air‐filled porosity) was fitted by a generalized additive model (GAM). Significant regressors were air‐filled porosity (?), soil depth, and the discrete diffusion direction. The model yields in all cases higher vertical diffusion efficiencies. The compaction factor did not yield a significant regressor of its own, i.e., the reduction of diffusivity in the compacted soil was the same as in low‐porosity samples of the undisturbed profile. To elucidate the role of sharing vertically and horizontally orientated pore space and a potential competition between diffusivity in different spatial directions, simple geometric models consisting of 3‐dimensionally crossed pores have been parameterized. These models provided a good explanation of the typical nonlinear Ds/D0(?) relationship. By simple one‐parameter correction (linear or power function), this mechanistic model could be fitted to the data. The one‐parameter correction of the geometric model could be a straightforward approach to consider direction dependence of measured diffusivities. However, by applying this approach to the observations the anisotropy effect was not clearly evident, which could be attributed to a changing Ds/D0(?) relationship with depth. As a reason for the preference of the vertical gas diffusion the dominance of vertical stresses and the activity of anecic earthworms are discussed. Direction dependency of gas diffusivity seems to be a basic feature of natural pore systems and has to be considered for modeling gas fluxes in soils. Generally, a preferential vertical diffusion direction reduces horizontal balancing and increases the heterogeneity of gas concentrations in the soil air. 相似文献
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M. Maier H. Schack‐Kirchner E. E. Hildebrand J. Holst 《European Journal of Soil Science》2010,61(6):877-887
Most studies implicitly consider soil carbon dioxide (CO2) efflux as the instantaneous soil respiration and thereby neglect possible changes in the amount of CO2 stored in the soil pore‐space. We measured the CO2 concentration profile of a well‐aerated soil continuously to evaluate the dynamics of the stored CO2 and to analyse the influence of environmental factors. For 25% of the observation period, changes in the amount of stored CO2 accounted for more than 15% of the soil‐CO2 efflux. The following factors were identified to interfere with steady‐state CO2 storage: (i) the fluctuating groundwater table altered the volume of the vadose zone, causing viscous airflow in air‐filled soil pores, (ii) atmospheric turbulence caused pressure‐pumping at the soil–atmosphere interface and (iii) intense rain greatly reduced the diffusivity of the uppermost soil layer. The friction velocity above the canopy was strongly correlated with fluctuations in the differential pressure between soil air and atmosphere, but no static pressure gradient could be detected because of the permeable nature of the soil. Unexpected short‐term declines in the soil CO2 concentration were observed during intense rainfall events. These declines were explained by the intensified CO2 saturation deficit of the infiltrating rainwater caused by the carbonate chemistry of the soil solution. 相似文献
99.
Sachs C Hildebrand M Volkening S Wintterlin J Ertl G 《Science (New York, N.Y.)》2001,293(5535):1635-1638
Scanning tunneling microscopy data revealed the atomic processes in propagating reaction fronts that occur in the catalytic oxidation of hydrogen on Pt(111). The fronts were also characterized on mesoscopic length scales with respect to their velocity and width. Simulations on the basis of a reaction-diffusion model reproduce the experimental findings qualitatively well. The quantitative comparison reveals the limitations of this traditional approach to modeling spatiotemporal pattern formation in nonlinear dynamics. 相似文献
100.