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991.
An enzyme-linked immunosorbent assay (ELISA) was used to detect antibodies to Campylobacter fetus subspecies venerealis in bovine vaginal mucus. The results of testing 168 samples from experimentally infected, field cases and control cows showed that the ELISA was more sensitive than the vaginal mucus agglutination test and also detected antibodies in earlier stages of infection. 相似文献
992.
Schoenmakers I Hazewinkel HA Voorhout G Carlson CS Richardson D 《The Veterinary record》2000,147(23):652-660
The skeletal development of three groups of great dane dogs, fed a diet composed according to the published nutritional requirements for dogs (controls) or with increased calcium or calcium and phosphorus content, was examined radiographically, histologically and biochemically. The diets were fed from the time the dogs first began eating food in addition to their dam's milk, until they were 17 weeks old. Thereafter, the calcium and phosphorus intakes of the dogs in the high calcium groups were normalised for a further 10 weeks. The dogs fed the high calcium diet without a proportionally high phosphorus intake became hypercalcaemic and hypophosphataemic, and had severe disturbances in skeletal development, growth, and mineralisation which were typical for rickets. After their calcium intake was normalised the lesions of rickets resolved but osteochondrotic lesions became apparent. The dogs fed the high calcium and phosphorus diet became slightly hypophosphataemic, their growth was retarded, and they had disturbances in skeletal development resembling osteochondrosis, which had only partly resolved after 10 weeks on the normal calcium and phosphorus diet. 相似文献
993.
I Bartov 《British poultry science》1985,26(4):473-481
Corticosterone-injected chicks fed on a diet based on sorghum gained less weight and accumulated more hepatic fat than chicks treated similarly and fed on a diet based on maize. The retention of nitrogen and dry matter and the apparent metabolisable energy of these diets were not affected by type of grain, either in corticosterone-injected or in untreated birds. A slight methionine deficiency in the maize diet resulted in an additional increase in the concentration of hepatic lipids in corticosterone-injected chicks. However, hepatic lipid concentration was not affected by either a deficiency or an excess of methionine in the diet based on sorghum. The dietary fat concentration of isocaloric and isonitrogenous diets and the energy concentration of diets containing similar energy-to-protein ratios did not affect the response of the chicks to corticosterone. There was a negative correlation between the relative weight gain of corticosterone-treated chicks and the relative hepatic fat content. The latter was positively correlated with relative abdominal fat pad size. 相似文献
994.
B. Román C. I. González Verdejo Z. Satovic M. D. Madrid J. I. Cubero S. Nadal 《Phytoparasitica》2007,35(2):129-135
Some species of the genusOrobanche are among the most devastating parasitic weeds, causing extensive damage in agricultural fields. Considering the difficult
control due to seed longevity in the soil, small seed size, high fecundity and a subterranean phase that allows them to parasitize
the host before they emerge and become evident, the development of diagnostic markers is highly recommended. In our study
we identified potential molecular diagnostic markers from the plastid genome in order to distinguish among the most importantOrobanche species attacking crops in Andalusia, the southern region of the Iberian Peninsula. The study has consideredO. crenata, O ramosa andO. cumana causing serious losses in legumes, solanaceous crops and sunflower fields, respectively, andO. minor that, although abundant in Andalusia, has to our knowledge not yet been found parasitizing agricultural hosts. We amplified
a non-coding region from the plastid genome, studied sequence differences among the amplified fragments and digested those
of the same length with selected restriction enzymes. Here, we propose a molecular protocol to distinguish the main parasitic
plants in crop fields of southern Spain. Different applications such as identification ofOrobanche seeds in soil or crop seed lots are discussed in order to offer right crop recommendations or to prevent new infestation
of parasite-free fields. Recommendations for further development of these diagnostic markers are also considered.
http://www.phytoparasitica.org posting Jan. 15, 2007. 相似文献
995.
996.
CAROLINA I. URRACA DEL JUNCO DARREN J. SHAW MARTIN P. WEAVER TOBIAS SCHWARZ 《Veterinary radiology & ultrasound》2011,52(6):634-639
Magnetic susceptibility artifacts as a result of metal debris from shoeing are a common problem in magnetic resonance imaging of the equine foot. Our purpose was to determine the suitability of radiography as a screening tool for the presence and location of metallic particles in the equine foot and to predict the size of the resultant magnetic susceptibility artifact. Radiography had 100% sensitivity for detection of metal particles ≥1 mm diameter. Metal particles of known diameter were placed within the hoof wall of 22 cadaver feet and scanned with a low‐field strength MR imaging unit (0.21 T). Magnetic resonance images were characterized by a signal void with a hyperintense rim and adjacent image distortion at the level of the known metal location. T2* weighted sequences were the most and fast spin echo (FSE) sequences the least affected. For all four sequences (T1 gradient echo [GRE]; T2*W GRE; T2 FSE; and short tau inversion recovery FSE), linear relationships were observed between particle and resultant artifact size. Magnetic susceptibility artifact size, location and superimposition on clinically relevant anatomic structures can be predicted radiographically for particles larger than 1 mm. If metal debris cannot be removed, the least artifact‐prone FSE sequences should be selected. 相似文献
997.
998.
The extent to which degenerative hip disorders in adult male turkeys result in pain was investigated in a two-period crossover experiment. The birds in six pens received daily injections of an anti-inflammatory steroid (betamethasone) during week 1 and control injections of physiological saline in week 3. The turkeys in the other six pens received saline in week 1 and steroid in week 3. Behavioural observations of the birds during weeks 1 and 3 revealed that the steroid treatment resulted in more spontaneous activity. The steroid-treated birds also showed speedier movement in a sexual activity test in weeks 1 and 3. Post mortem examination revealed that all the turkeys were suffering from degenerative hip disorders. It is concluded that degenerative hip disorders in adult male turkeys result in a state of chronic pain which inhibits spontaneous activity and sexual activity. 相似文献
999.
M.L. Henery M. Henson I.R. Wallis C. Stone W.J. Foley 《Forest Ecology and Management》2008,255(10):3642-3651
A genetic basis for variation in resistance to defoliating insects within Eucalyptus species has been identified in many studies. This variation has frequently been ascribed to variation in secondary metabolites but studies investigating variation in resistance to defoliation by paropsine chrysomelids have failed to correlate foliar chemistry with resistance. We found that the extent of crown damage due to defoliation by Paropsis atomaria (Chrysomelidae: Colepoptera) in two matched progeny trials of Eucalyptus grandis was a heritable trait that exhibited a strong correlation with provenance latitude. Despite this, neither foliar nitrogen or concentrations of a recently discovered group of compounds, formylated phloroglucinol compounds, could account for significant variation in defoliation. We also investigated whether defoliation in the field could be predicted from foliar near-infrared reflectance spectra. Such an approach takes into account all compositional variation simultaneously rather than relying on a restricted number of measured traits. Modified partial least squares regression models performed poorly in predicting variation in crown defoliation between trees within a site primarily due to the high level of variability and coarseness of the calibration data. Discriminant analyses however demonstrated a consistent difference between spectra from trees in families suffering low level defoliation from families more susceptible to defoliation by P. atomaria suggesting chemical differences between the two groups are important in determining resistance to this insect. 相似文献
1000.
Soybean nodules subjected to water stress showed lowered C2H2 reducing activity and O2 uptake, but enhanced CO2 and ethanol evolution. Similar results were obtained with waterlogged nodules. The effects of stress could be partially or completely overcome by increaseing the O2 supply. It is concluded that both water deficiency and excess may depress nitrogenase activity (C2H2 reduction) by restricting supplies of intermediates from aerobic pathways. At the same time fermentative pathways are stimulated and could lead to inhibitory concentrations of ethanol being produced. Both symbionts possess systems for ethanol production. 相似文献