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991.
Costa CT Bevilaqua CM Maciel MV Camurça-Vasconcelos AL Morais SM Monteiro MV Farias VM da Silva MV Souza MM 《Veterinary parasitology》2006,137(3-4):306-310
Gastrointestinal nematode control has been performed through use of anthelmintics. However, the development of resistant populations has required research into new alternatives. There are popular reports about anti-parasitic activity of Azadirachta indica in animals and plants. The aim of this study was to evaluate the anthelmintic activity of A. indica after feeding sheep with the dried leaves. In this experiment, 40 sheep were allotted into four treatment groups. Group I received a treatment of A. indica dry leaves mixed in a concentrate at a rate of 0.1 g/kg dose for 3 months. Group II was treated with double the dose of Group I. Group III was treated with closantel (Diantel) at the manufacturer-recommended dose once at the beginning of the study and Group IV was not treated. To compare treatment effects, the following parameters were evaluated: egg count per gram of feces (EPG), worm burden, weight gain and haematocrit. EPG and worm burden results were statistically evaluated using the Kruskal-Wallis test. Haematocrit and live weight gain were submitted to analysis of variance (ANOVA) and the means evaluated by Tukey's test with 95% probability. None of the evaluated parameters of the treatment groups were statistically different when compared to the control group, demonstrating that, with the protocol used, A. indica has no anthelmintic effect. 相似文献
992.
Nematodes from the ventral colon of 31 adult horses, 24 males and 9 females, in the metropolitan region of the state of Rio de Janeiro were analysed. There were 53,444 (86.4%) adults of the total recovered strongylid nematodes. They belonged to 21 species of Cyathostominae and seven of Strongylinae. Larval forms made up 13.6% (8407) of the total recovered, and 49% of the strongylid nematodes were observed in ventral colon. The most prevalent and abundant species were Cyathostomum tetracanthum, Cylicocyclus nassatus, Cylicostephanus minutus, Cylicostephanus longibursatus, Cylicostephanus leptostomus, Cylicostephanus calicatus and Cylicostephanus goldi, corresponding to 93.2% of the total adult population; these species were classified as central species, except C. goldi; and other species were classified as secondary (n = 8) and satellite (n = 14). The low Green's aggregation index, presented to central species, indicated high dispersion because they were found in a greater number of infracommunities and were proven by the greater prevalence. Only 12.1% of the horses were uninfected or infected by a single species; the other infections were multiple, ranging from 3 to 23 species. 相似文献
993.
This review seeks to examine the extreme response of isolated somatic plant cells of apical meristematic tissues of mature conifer trees towards specific stress conditions in vitro resulting in somatic embryogenesis.Signal molecules regulating embryo development have been described in angiosperms,but very little is known about somatic rejuvenation in conifers.Recent studies on cloning of mature conifers provide new perspectives on signal molecules on cellular dedifferentiation into the embryogenic pathway.Our recent studies show that signal molecules such as butenolide,calcium ions,salicylic acid,antioxidants,amino acids,triacontanol and 24-epibrassinolide all play an important role in the conversion of somatic cells into an embryogenic pathway in many recalcitrant pines.This constitutes a major breakthrough in forest biotechnology with many practical applications in clonal forestry. 相似文献
994.
Carmen Sotelo Montes John C. Weber Dimas A. Silva Clarice Andrade Graciela I. B. Mu?iz Rosilei A. Garcia Antoine Kalinganire 《Annals of Forest Science》2012,69(6):747-756
? Context
There is little information about inter- and intra-specific variation in fuelwood properties of trees/shrubs in West Africa.? Aims
We studied variation in fuelwood properties of Balanites aegyptiaca, Combretum glutinosum, Guiera senegalensis, Piliostigma reticulatum, and Zizyphus mauritiana in the Sahelian and Sudanian ecozones of Mali.? Methods
Trees were sampled on different soil (sandy, sandy/loam, or rocky), land use (parkland agroforest or woodland), and terrain (flat, temporarily flooded, or hill slope) types in five regions extending from the drier eastern to the more humid western parts of Mali. Basic density, volatile matter, fixed carbon, ash content, moisture content, gross calorific value, and fuel value index were measured for each tree and adjusted for tree age.? Results
All fuelwood properties differed significantly among species, but there were significant species by region interactions. Most fuelwood properties of four species differed significantly among regions. Soil and/or land use type had significant effects on a few fuelwood properties of four species.? Conclusion
In general, fuelwood production is recommended in all regions for G. senegalensis, in drier regions for B. aegyptiaca and C. glutinosum, in more humid regions for Z. mauritiana, and on rocky soils for all species. Fuelwood production of P. reticulatum is not recommended. 相似文献995.
Francisco Rodríguez y Silva Juan Ramón Molina-Martínez 《European Journal of Forest Research》2012,131(3):571-582
Fire behavior modeling systems are important in predicting wildfire risk, fire growth, and fire effects. However, simulation
software requires a new fuel modeling to include fuel treatments, prescribed fire and the transition to crown fire. The thirteen
Rothermel models are insufficient in completely representing Mediterranean ecosystems. In this sense, the new American modeling
includes five fuel types, requiring the acquisition of hybrid models made up of the mixture of grass and shrub and the grass
or shrub mixed with litter from forest canopy. Respecting meteorological conditions and shrub characteristics, field studies
have shown significant differences between American and Mediterranean models. As a consequence, the definition of new Mediterranean
models requires the adjustment of specific parameters such as fuel load by category (live and dead) and particle size class
(1-, 10- and 100-h time-lag), fuelbed depth and surface area-to-volume ratio. These new parameters were obtained in situ of
sample itineraries, prescribed fires, and forest fires. The availability of this new modeling, validated on a field of regional
scale, will facilitate preventive planning and management as well as an efficient application of suppression techniques, both
ground and aerial operations, required in defending a territory against forest fires. 相似文献
996.
Alexandre Alonso Alves Carla Cristina Gonçalves Rosado Danielle Assis Faria Lúcio Mauro da Silva Guimarães Douglas Lau Sérgio Hermínio Brommonschenkel Dario Grattapaglia Acelino Couto Alfenas 《Euphytica》2012,183(1):27-38
Eucalypts are susceptible to a wide range of diseases. One of the most important diseases that affect Eucalyptus plantations worldwide is caused by the rust fungus Puccinia psidii. Here, we provide evidence on the complex genetic control of rust resistance in Eucalyptus inter-specific hybrids, by analyzing a number of full-sib families that display different patterns of segregation for rust
resistance. These families are totally unrelated to those previously used in other inheritance studies of rust resistance.
By using a full genome scan with 114 genetic markers (microsatellites and expressed sequence tag derived microsatellites)
we also corroborated the existence and segregation of a resistance locus, explaining 11.5% of the phenotypic variation, on
linkage group 3, corresponding to Ppr1. This find represents an additional validation of this locus in totally unrelated pedigree. We have also detected significant
additive × additive digenic interactions with LOD >10.0 on several linkage groups. The additive and epistatic QTLs identified
explain between 29.8 and 44.8% of the phenotypic variability for rust resistance. The recognition that both additive and non-additive
genetic variation (epistasis) are important contributors to rust resistance in eucalypts reveals the complexity of this host-pathogen
interaction and helps explain the success that breeding has achieved by selecting rust-resistant clones, where all the additive
and non-additive effects are readily captured. The positioning of epistatic QTLs also provides starting points to look for
the underlying genes or genomic regions controlling this phenotype on the upcoming E. grandis genome sequence. 相似文献
997.
998.
Pimenta J Dias FM Marques CC Baptista MC Vasques MI Horta AE Barbas JP Soares R Mesquita P Cabrita E Fontes CM Prates JA Pereira RM 《Reproduction in domestic animals》2012,47(2):196-202
The function of prion‐like protein Doppel was suggested to be related to male fertility. In this study, the importance of ovine Doppel polypeptide on spermatozoa capacitation and fertilization was evaluated. After refolding, recombinant Doppel (rDpl) was supplemented with different concentrations (40, 80 or 190 ng/ml) to ovine spermatozoa during the capacitation process. In experiment 1, post‐thawed ovine spermatozoa were incubated with different concentrations of rDpl during 1 h for swim‐up, and changes in sperm motility, concentration, vigour, viability and capacitation were monitored (10 replicates). In experiment 2, the fertilization ability of post‐swim‐up spermatozoa incubated as above was tested through heterologous fertilization of bovine in vitro matured oocytes (n = 423, three replicates). Regardless of dosage, rDpl improved (p ≤ 0.03) spermatozoa viability. Sperm individual motility and vigour were the highest (p ≤ 0.04) for the group receiving 190 ng/ml rDpl. Sperm supplemented with the highest doses of rDpl achieved higher (p = 0.02) fertilization rates (56.0 ± 3.0%) than control (39.1 ± 2.2%) and 40 ng/ml rDpl (39.8 ± 2.7%). Preliminary data suggest that Doppel protein may enhance in vitro spermatozoa fertilizing ability. 相似文献
999.
Gabrielle C. Freitas Marina G. Monteiro Carvalho Mori da Cunha Kleber Gomes Jo?o P. Monteiro Carvalho Mori da Cunha Monique Togni Ney L. Pippi Adriano B. Carregaro 《Canadian journal of veterinary research》2012,76(3):201-208
This study compared acid-base and biochemical changes and quality of recovery in male cats with experimentally induced urethral obstruction and anesthetized with either propofol or a combination of ketamine and diazepam for urethral catheterization. Ten male cats with urethral obstruction were enrolled for urethral catheterization and anesthetized with either ketamine-diazepam (KD) or propofol (P). Lactated Ringer’s solution was administered by intravenous (IV) beginning 15 min before and continuing for 48 h after relief of urethral obstruction. Quality of recovery and time to standing were evaluated. The urethral catheter was maintained to measure urinary output. Hematocrit (Hct), total plasma protein (TPP), albumin, total protein (TP), blood urea nitrogen (BUN), creatinine, pH, bicarbonate (HCO3−), chloride, base excess, anion gap, sodium, potassium, and partial pressure of carbon dioxide in mixed venous blood (pvCO2) were measured before urethral obstruction, at start of fluid therapy (0 h), and at subsequent intervals. The quality of recovery and time to standing were respectively 4 and 75 min in the KD group and 5 and 16 min in the P group. The blood urea nitrogen values were increased at 0, 2, and 8 h in both groups. Serum creatinine increased at 0 and 2 h in cats administered KD and at 0, 2, and 8 h in cats receiving P, although the values were above the reference range in both groups until 8 h. Acidosis occurred for up to 2 h in both groups. Acid-base and biochemical stabilization were similar in cats anesthetized with propofol or with ketamine-diazepam. Cats that received propofol recovered much faster, but the ketamine-diazepam combination was shown to be more advantageous when treating uncooperative cats as it can be administered by intramuscular (IM) injection. 相似文献
1000.
Solcà Mda S Guedes CE Nascimento EG Oliveira GG dos Santos WL Fraga DB Veras PS 《Veterinary parasitology》2012,184(2-4):133-140
Because infected dogs are widely considered to be the main domestic reservoir for Leishmania infantum (syn Leishmania chagasi) parasites in Brazil, the diagnosis of canine visceral leishmaniasis (CVL) must be made both accurately and promptly. The present study attempted to standardize a conventional polymerase chain reaction (cPCR) protocol for the detection of L. infantum DNA in canine spleen samples. Quantitative PCR (qPCR) technique was used to confirm the presence of Leishmania DNA in the canine spleen fragments. A comparison was made between the efficacies of these molecular diagnostic techniques and conventional parasitological and serological methods. cPCR protocols for spleen samples were standardized using primers that amplify a 145 bp fragment, located at the parasite kinetoplast minicircle. The genus specificity of the cPCR protocol was assessed by its inability to amplify the DNA of other common canine pathogens, such as Ehrlichia canis, Babesia canis, Toxoplasma gondii and Trypanosoma cruzi. cPCR protocol sensitivity was tested by assessing the reaction detection limit, determined to be 10 fg of L. infantum reference strain DNA, which corresponds to a range of 0.03-0.1 parasites per fragment. Standardized cPCR protocol was used to detect the presence of Leishmania in 45 dog spleen samples. Our results showed that 40% of the spleen fragment cultures were positive for Leishmania parasites, 58% of the dog serum samples tested positive using ELISA, and parasite DNA was detected in 44% using qPCR, while 47% of the spleen samples using cPCR. Diagnostic methods performance was assessed and revealed a better degree of ascertainment for cPCR when compared to other diagnostic methods. The sensitivity of ELISA was 83.3%, qPCR was 83.3%, and cPCR was 88.9%; PPV for ELISA was 57.7%, qPCR was 75% and cPCR was 76.2%; the Kappa coefficients were found to be 0.40 (fair) for ELISA, 0.64 (substantial) for qPCR and 0.68 (substantial) for cPCR. In both oligosymptomatic and polysymptomatic dogs, cPCR revealed the better performance analysis when compared to other diagnostic methods. The findings presented herein establish cPCR as the most indicated test to detect Leishmania when compared to the other two diagnostic methods evaluated. Despite the fact that the qPCR protocol provides a highly accurate quantification of parasites when targeting the SSU rRNA gene, this technique does not significantly improve the diagnosis of CVL when compared with the performance of the cPCR protocol, which focused on the kinetoplast minicircle. 相似文献