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171.
Samuel Vasconcelos Valadares Víctor Hugo Alvarez V. Jefferson Luiz de Aguiar Paes Caio Buainain Lins Roberto Ferreira Novais 《Communications in Soil Science and Plant Analysis》2017,48(15):1834-1842
We assessed the sensitivity of mixed exchange resin (MER) and Mehlich-3 (M3) to calcium-bound phosphate (Ca-P) in Oxisols. These methods were compared with Mehlich-1 (M1) and anion exchange resin (AER), which have high and low sensitivity, respectively, to this soil P form. We used maize (Zea mays L.) as a test plant. Three samples from two Oxisols were treated with five ratios of Triple Superphosphate—TS and Bayóvar Phosphate Rock—BPR (0 + 100; 25 + 75, 50 + 50, 75 + 25 and 100 + 0% TS + BPR). The MER extracted more P than AER and M3 at the highest BPR:TS ratios (high Ca-P) and similar quantities at the higher TS:BPR ratios (low Ca-P) for two soil samples. Unlike M1-extracted P, M3-P, AER-P, and MER-P positively correlated with maize dry matter production and P uptake. Mehlich-3 and MER were suitable to assess P availability in high Ca-P Oxisols. 相似文献
172.
M. Ângelo Rodrigues Sandra Afonso Isabel Q. Ferreira Margarida Arrobas 《Archives of Agronomy and Soil Science》2017,63(5):626-637
The adaptation of stevia to the growing conditions of NE Portugal is assessed, including the tolerance of this species to cold temperatures, and the potential to produce biomass when grown as an annual crop and when subjected to various nitrogen (N) rates and two harvesting regimes. Almost all the plants died during the winter of 2014 (minimum temperatures peaked at ?8.0°C), making it necessary to replant the crop the following spring. With the best cutting regime (double cut) and N rate (150 kg N ha?1), 1514.4 and 2390.0 kg ha?1 of dry leaves were produced, respectively, in 2014 and 2015. Leaf chlorophyll concentrations estimated by the SPAD (Soil and Plant Analysis Development)-502 chlorophyll meter and a NDVI (Normalized Difference Vegetation Index) carried out by the Field Scout CM 1000 spectroradiometer showed significant differences among N rates, proving to be good indicators of plant N nutritional status. Based on the leaf analysis, provisional sufficiency ranges for N are proposed, namely 25–35 g kg?1 for mid-summer and 15–25 g kg?1 for early autumn. The fluorescence of chlorophyll a and the transient fluorescence intensity performed by the OS-30p+ fluorometer failed to show any stress induced by no-N control treatments in comparison to N-treated plants. 相似文献
173.
Molecular and biological characterization of the begomovirus isolate BR:LNS2:Pas:01, obtained from yellow passionfruit plants in Livramento de Nossa Senhora, Bahia state, Brazil, was carried out. Sequence analysis demonstrated that the BR:LNS2:Pas:01 DNA‐A had highest nucleotide sequence identity with Tomato chlorotic mottle virus (77%) and had five ORFs corresponding to the genes cp, rep, trap, ren and ac4. The DNA‐B had highest nucleotide sequence identity with Tomato yellow spot virus (74%) and two ORFs corresponding to the genes mp and nsp. These identity values indicate that this isolate represents a new begomovirus species, for which the name Passionfruit severe leaf distortion virus (PSLDV), is proposed. Phylogenetic analysis clustered the PSLDV DNA‐A and ‐B in a monophyletic branch with Brazilian tomato‐infecting begomoviruses. The isolate’s host range was restricted to species from the Passifloraceae and Solanaceae. PSLDV‐[BR:LNS2:Pas:01] was capable of forming pseudorecombinants with tomato‐infecting begomoviruses, reinforcing its close relationship with these viruses and suggesting a possible common origin. However, the virus was not capable of infecting tomato. 相似文献
174.
Pythium ultimum is a soil pathogen that can cause seed decay and damage to roots in common bean. In this study, the response of a set of 40 common bean genotypes to P. ultimum and inheritance of the resistance in the 92 F? recombinant inbred lines (RIL) developed from a cross between Xana and Cornell 49242 was investigated by using emergence rate and seedling vigor. Emergence of the 40 genotypes showed a significant association between white seed coat and response to this pathogen. Among these, 11 common bean genotypes, all with colored seeds, exhibited a high percentage of emergence and seedling vigor not significantly different (P > 0.05) to noninoculated plants. Response of the RIL population revealed both qualitative and quantitative modes of inheritance. A major gene (Py-1) controlling the emergence rate was mapped in the region of the gene P, a basic color gene involved in control of seed coat color, located on LG 7. Using the RIL subpopulation with colored seeds, a significant quantitative trait loci (QTL) associated with the emergence rate (ER3(XC)) and another with seedling vigor (SV6(XC)) were identified on the LG 3 and 6, respectively. QTL SV6(XC) was mapped in the region of the gene V, another gene involved the genetic control of color. QTLs associated with seed traits were mapped in the same relative position as regions involved in responses to P. ultimum suggesting the possible implication of avoidance mechanisms in the response to this pathogen. 相似文献
175.
176.
M.H.C. Aquino A.L.L. Filgueiras K.R.N. Santos M.C.S. Ferreira A. Tibana 《Research in veterinary science》2010,88(2):214-217
To compare the genotypes of Campylobacter jejuni and Campylobacter coli isolates of human and animal origin collected in Rio de Janeiro City, 30 C. jejuni and 35 C. coli isolates from animal sources (n = 45) and human patients with gastroenteritis (n = 20) were genotyped by PCR-based techniques, namely random amplified polymorphic DNA (RAPD-PCR) and enterobacterial repetitive intergenic consensus sequence (ERIC-PCR). RAPD-PCR identified 50 types and ERIC-PCR identified 22 genotypes, among the 65 Campylobacter isolates. Both PCR methods discriminated the C. jejuni and C. coli groups of isolates. Combining the results of both methods, no single genotype was shared between isolates from human and animal sources. Two groups of two C. coli isolates each with identical genotypes were found among poultry and pig isolates. A high level of genetic diversity observed among the Campylobacter isolates suggests lack of overlap between isolates from different sources. 相似文献
177.
Raquel M. Marques António Costa-e-Silva Artur P. Águas Luzia Teixeira Paula G. Ferreira 《Veterinary research communications》2010,34(8):659-668
Rabbit Haemorrhagic Disease (RHD) is a lethal infection caused by calicivirus that kills 90% of the infected adult rabbits
within 3 days. The calicivirus replicates in the liver and causes a fulminant hepatitis. Most studies on the pathology of
RHD have been focused on the fulminant liver disease. This may not be the only mechanism in the pathogenesis of RHD: calicivirus
infection may also induce leukopenia in the infected adult rabbits. We show now by flow cytometry analysis that the calicivirus
induces an early decrease in B and T cells, in both spleen and liver. The depletion of B and T cells was associated with apoptosis
labelled by annexin V. These changes occurred in rabbits before they showed enzymatic evidence of liver damage and persisted
after liver transaminase values were very high. We conclude that depletion of lymphocytes caused by the calicivirus infection
precedes or attends liver damage. The relative contribution of this lymphocyte depletion for the pathogenesis of the fatal
calicivirus infection of rabbits remains to be investigated. 相似文献
178.
Buim MR Buzinhani M Yamaguti M Oliveira RC Mettifogo E Timenetsky J Ferreira AJ 《Comparative immunology, microbiology and infectious diseases》2010,33(1):15-23
Mycoplasma synoviae (MS) is an important avian pathogen may cause both respiratory disease and joint inflammation synovitis in poultry, causing economic losses to the Brazilian poultry industry. The genotypic variation in 16S rRNA gene is unknown. Partial sequences of 16S rRNA gene of 19 strains of M. synoviae were sequenced and analyzed in order to obtain molecular characterization and evaluation of the genetic variability of strains from distinct Brazilian areas of poultry production. Different polymorphic patterns were observed. The number of polymorphic alterations in the studied strains ranged from 0 to 6. The nucleotide variations, including deletion, insertion and substitutions, ranged from 3 to 5. The genotypic diversity observed in this study may be explained by spontaneous mutations that may occur when a lineage remains in the same flock for long periods. The culling and reposition in poultry flocks may be responsible for the entry of new strains in different areas. 相似文献
179.
180.
Renato G Credie Francisco J Teixeira Neto Tatiana H Ferreira Antônio JA Aguiar Fabio C Restitutti José E Corrente 《Veterinary anaesthesia and analgesia》2010,37(3):240-249
ObjectiveTo investigate the effects of methadone on the minimum alveolar concentration of isoflurane (ISOMAC) in dogs.Study designProspective, randomized cross-over experimental study.AnimalsSix adult mongrel dogs, four males and two females, weighing 22.8 ± 6.6 kg.MethodsAnimals were anesthetized with isoflurane and mechanically ventilated on three separate days, at least 1 week apart. Core temperature was maintained between 37.5 and 38.5 °C during ISOMAC determinations. On each study day, ISOMAC was determined using electrical stimulation of the antebrachium (50 V, 50 Hz, 10 mseconds) at 2.5 and 5 hours after intravenous injection of physiological saline (control) or one of two doses of methadone (0.5 or 1.0 mg kg?1).ResultsMean (±SD) ISOMAC in the control treatment was 1.19 ± 0.15% and 1.18 ± 0.15% at 2.5 and 5 hours, respectively. The 1.0 mg kg?1 dose of methadone reduced ISOMAC by 48% (2.5 hours) and by 30% (5 hours), whereas the 0.5 mg kg?1 dose caused smaller reductions in ISOMAC (35% and 15% reductions at 2.5 and 5 hours, respectively). Both doses of methadone decreased heart rate (HR), but the 1.0 mg kg?1 dose was associated with greater negative chronotropic actions (HR 37% lower than control) and mild metabolic acidosis at 2.5 hours. Mean arterial pressure increased in the MET1.0 treatment (13% higher than control) at 2.5 hours.Conclusions and clinical relevanceMethadone reduces ISOMAC in a dose-related fashion and this effect is lessened over time. Although the isoflurane sparing effect of the 0.5 mg kg?1 dose of methadone was smaller in comparison to the 1.0 mg kg?1 dose, the lower dose is recommended for clinical use because it results in less evidence of cardiovascular impairment. 相似文献