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391.
392.
Marioni-Henry K Schwarz T Weisse C Muravnick KB 《Journal of the American Animal Hospital Association》2007,43(6):347-351
A 13-year-old, castrated male Siamese cat was presented with a 4-month history of recurrent seizures and bilateral conjunctivitis and rhinitis. Computed tomography of the brain and nose revealed a cystic lesion in the cranial cavity that compressed the brain and invaded the nose. Nasal biopsy revealed a nasal adenocarcinoma. The cat was treated with intermittent antibiotics, phenobarbital, piroxicam, and chemoembolization; it survived for 2 years after diagnosis. 相似文献
393.
Manley PA Adams WM Danielson KC Dueland RT Linn KA 《Journal of the American Veterinary Medical Association》2007,230(2):206-210
OBJECTIVE: To compare long-term outcomes of juvenile pubic symphysiodesis (JPS) and triple pelvic osteotomy (TPO) in dogs with hip dysplasia. DESIGN: Prospective clinical trial. ANIMALS: 18 dogs with hip dysplasia (ie, distraction index > or = 0.5 in at least 1 hip joint and no, mild, or moderate radiographic evidence of degenerative joint disease [DJD]). PROCEDURES: Dogs between 4 and 5.5 months old at enrollment were assigned to undergo JPS, and dogs between 5 and 12 months old were assigned to undergo TPO. All dogs were reexamined at 2 years of age. RESULTS: At 2 years of age, there were no significant differences between groups in regard to lameness scores, angle of extension of the hip joints, distraction index, peak vertical force, acetabular angle, radiographic DJD score, or owner-assigned scores of clinical function. Dorsal acetabular rim angle was significantly higher in dogs that underwent JPS than in dogs that underwent TPO. For dogs that underwent TPO, dorsal acetabular rim angle was significantly decreased and acetabular angle was significantly increased at 2 years of age, compared with values obtained prior to surgery. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that JPS and TPO have similar effects on hip joint conformation in dogs with moderate to severe hip dysplasia but that neither procedure eliminates the hip joint laxity characteristic of hip dysplasia or the progression of degenerative changes. 相似文献
394.
Small-scale Forestry - Increased recognition of forest fragments as integral components of multi-functional landscape mosaics creates opportunity to broaden approaches to forest management in rural... 相似文献
395.
Gadgil P Hachmeister KA Smith JS Kropf DH 《Journal of agricultural and food chemistry》2002,50(20):5746-5750
Alkylcyclobutanones have been recognized as chemical markers of irradiated lipid-containing foods since 1970. They are important because they are produced solely as a result of irradiation and not any other processing method. This study investigated the formation of 2-dodecylcyclobutanone (2-DCB) and 2-tetradec-5'-enylcyclobutanone (2-TDCB) in irradiated ground beef patties from commercial and noncommercial sources. Patties were irradiated using a (60)C source (gamma-irradiation) and electron beam irradiation, at five targeted absorbed doses of 0.5, 1.0, 2.5, 5.0, and 7.0 kGy. Commercially available irradiated patties were also studied. A supercritical fluid extraction (SFE) procedure was optimized and used for the extraction and isolation of the alkylcyclobutanones. Samples can be used for extraction without a prior cleanup step, which makes this procedure rapid and convenient to use. Identification and quantitation of the cyclobutanones were done by gas chromatography-mass spectroscopy. 2-DCB was detected in all of the irradiated samples (including commercial patties), and its concentration increased linearly with the irradiation dose. Electron beam irradiation produced a greater amount of 2-DCB compared to gamma-irradiation at dose levels >2.5 kGy. 2-TDCB was detected only at the two higher irradiation doses, whereas both marker compounds were not detected in the non-irradiated samples. 相似文献
396.
Kathleen Neumann Berien S. Elbersen Peter H. Verburg Igor Staritsky Marta Pérez-Soba Wim de Vries Willem A. Rienks 《Landscape Ecology》2009,24(9):1207-1222
Livestock remains the world’s largest user of land and is strongly related to grassland and feed-crop production. Assessments
of environmental impacts of livestock farming require detailed knowledge of the presence of livestock, farming practices,
and environmental conditions. The present Europe-wide livestock distribution information is generally restricted to a spatial
resolution of NUTS 2 (province level). This paper presents a modelling approach to determine the spatial distribution of livestock
at the landscape level. Location factors for livestock occurrence were explored and applied to consistent and harmonized EU-wide
regional statistics to produce a detailed spatial distribution of livestock numbers. Both an expert-based and an empirical
approach were applied in order to disaggregate the data to grid level. The resulting livestock maps were validated. Results
differ between the two downscaling approaches but also between livestock types and countries. While both the expert-based
and empirical approach are equally suited to modelling herbivores, in general, the spatial distribution of monogastrics can
be better modelled by applying the empirical approach. 相似文献
397.
Fred E. Palmer Kathleen A. Ballard Frieda B. Taub 《Aquaculture (Amsterdam, Netherlands)》1975,6(4):319-331
A multi-stage, continuous culture apparatus has been designed and tested for the production of algae for larval molluscs and crustacea. A single-line system produced a maximum of 2.4 × 1011 cells/day, or 5 g ash-free dry weight of Monochrysis lutheri. Multiple-line systems are recommended for hatcheries. The flow rate affected algal cell density, yield, biomass, protein level, and residual nitrate.Maximal cell yield occurred at 10 I flow per day, a dilution rate of 63% of the volume of the first growth carboy, or 30% of the volume of the total system. The system is also adaptable to growth of larger planktonic algae or mixed cultures of algae and protozoa and/or rotifers. 相似文献
398.
We report here validation of the Immulite 2000 Xpi cortisol immunoassay (Siemens; with kit lot numbers <550) for measurement of urine cortisol in dogs, with characterization of the precision (CV), accuracy (spiking-recovery [SR] bias), and observed total error (TEo = bias + 2CV) across the reportable range. Linearity assessed by simple linear regression was excellent. Imprecision, SR bias, and TEo increased markedly with decreasing urine cortisol concentration. Interlaboratory comparison studies determined range-based (RB) bias and average bias (AB). The 3 biases (SR, RB, and AB) and resulting TEo differed markedly. At 38.6 and 552 nmol/L (1.4 and 20 μg/dL), between-run CVs were 10% and 4.5%, respectively, and TEoRB were ~30% and 20%, respectively, similar to observations in serum in another validation study. These analytical performance parameters should be considered for urine cortisol:creatinine ratio (UCCR) result interpretation, given that, for any hypothetical errorless urine creatinine measurement, the error % on UCCR mirrors the error % on urine cortisol. Importantly, there is no commonly used interpretation threshold for UCCR, given that UCCR varies greatly depending on measurement methods and threshold computation. To date, there is no manufacturer-provided quality control material (QCM) with target values for urine cortisol with an Immulite; for Liquicheck QCM (Bio-Rad), between-run imprecision was ~5% for both QCM levels. Acceptable QC rules are heavily dependent on the desired total allowable error (TEa) for the QCM system, itself limited by the desired clinical TEa. 相似文献
399.
The 10,700 km2 region of northwestern Oregon, USA, is dominated by mountainous forested landscapes fringed by agricultural lands and rapidly
expanding urban areas. The Douglas-fir/western-hemlock trees, admixed with other species, in the mild, moist regional climate
with rich soils are among the most highly productive of temperate forests. Timber harvest has been the dominant land use for
much of this century. Many current forest stands are planted, and have the potentials to be managed and shaped for a variety
of traditional and evolving forestry objectives. The ages, resilience and productivity of these forests and mosaics of land
ownerships permit a variety of future scenarios of forested landscapes, constrained largely by capacities of social organizations
to plan and execute management for desired future conditions.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
400.
The objectives of this study were to show that: (a) a herbicide, such as ametryn, which interferes with the photosynthetic electron transport system, causes nitrite to accumulate in illuminated leaves and (b) that nitrite is toxic and contributes to the herbicidal damage and death of the plant. Tests were conducted on wheat seedlings grown on 5 mM nitrate, 5 mM ammonia, and zero nitrogen. Ametryn treatment decreased in vivo and in vitro nitrate reductase activity (NRA) within a 26-hr period. In vivo NRA decreased more rapidly than in vitro NRA. Compared with control tissue, only 3% in vivo NRA remained at the end of 26 hr. The in vivo assay conducted in light confirmed the inhibition of photosynthetic electron flow by ametryn within the leaf tissue. Nitrate-grown, ametryn-treated plants accumulated nitrite and, after 10 days were the only plants that were completely desiccated and dead. Ammonia- and zero-nitrogen, ametryn-treated plants did not accumulate nitrite, were only partially chlorotic after the 10-day period, and were still living. Low levels of NO(X) (NO2 and/or NO) emissions were demonstrated by nitrate-grown ametryn-treated plants. 相似文献