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941.
Some species of the genus Trifolium are well-known for their content of isoflavones, which are natural compounds showing health-promoting activities. Until recently, only a few species of this genus have been characterized with respect to their composition. In the present study, 57 Trifolium species have been analyzed for their contents of isoflavones, phenolic acids, flavonoids, and clovamides. The cluster analysis of experimental data allowed us to identify a number of species, which should be of interest as potential sources of these metabolites. The isoflavone contents of the three species ( T. heldreichianum, T. scabrum, and T. subterraneum) had extremely high amounts of these compounds, reaching 7-9% of dry matter, and the concentration in a number of other species was higher or at least comparable to the amounts occurring in T. pratense, one of the major isoflavone sources for the nutraceutical industry. Several species contained high amounts of all four analyzed groups of phenolics (isoflavones, phenolic acids, flavonoids, and clovamides). These species may also be of great interest as the association of several groups of active molecules is highly desired for effective disease prevention. 相似文献
942.
Folic acid (FA) is used, in many countries, in nutritional supplements or for the fortification of cereals and their products. It is also used in vitamin pills. Recently, it was reported that folates may act as antioxidants; therefore, in the present study, the effect of pH of the surrounding medium on the radical-scavenging activity of FA and its reduced forms [dihydrofolic acid (DHF), tetrahydrofolic acid (THF), 5-methyltetrahydrofolic acid (5-MTHF), and 5-formyltetrahydrofolic acid (5-FTHF)] was investigated. It was found that radical-scavenging activities of folates, measured in the trolox equivalent antioxidant capacity (TEAC) assay, are strongly pH-dependent. FA is a better radical scavenger at acid and basic pH than at neutral pH. Reduced forms of FA are better radical scavengers at acidic pH values than at neutral and basic pH values, with exception of 5-FTHF for which, at a pH higher than 5.0, an increase of the radical-scavenging activity with an increasing pH of the medium is observed. The results of the present study indicate that possible health effects of folates associated with their radical-scavenging activity will vary depending upon the pH of body fluid or tissue considered. 相似文献
943.
José F. Vouillamoz Anna Schneider M. Stella Grando 《Genetic Resources and Crop Evolution》2007,54(5):1095-1104
According to Pliny the Elder and other Greco-Roman geoponics, Raetica was a famous white grape as well as a white wine produced in Raetia, a Province of the Roman Empire. Does Raetica grape have modern descendants? Etymologically and geographically, the white ‘Rèze’ from Valais (Switzerland) would be the best candidate. Using available microsatellite data, we searched for relatives of ‘Rèze’ in our database containing over 1,700 genotypes of grape cultivars from all over the world. Twelve cultivars showing putative first-degree (parent–offspring or full-siblings) or second-degree (grandparent–grandoffspring, uncle–nephew or half-siblings) relationships with ‘Rèze’ were then analysed at 60 microsatellite markers. Calculation of allele sharing and likelihood ratios between competing relationship categories revealed that four cultivars had parent–offspring relationship with ‘Rèze’: ‘Cascarolo Bianco’ (Piedmont, Italy), ‘Arvine Grande’ (Valais, Switzerland), ‘Groppello di Revò’ and ‘Nosiola’ (Trentino, Italy). Given that some of these are also said to be Raetica descendants, we may well be on the tracks of Pliny the Elder’s Raetica grape. However, there is no evidence about the identity of Raetica. Analysis of ancient DNA of grape pips excavated from archaeological sites of the Roman times might provide key information. Our first attempts were unsuccessful, but analysis of additional samples and optimisation of the method could provide groundbreaking results about the identity of the grapes cultivated in classical antiquity. 相似文献
944.
945.
Groenewald M Barnes I Bradshaw RE Brown AV Dale A Groenewald JZ Lewis KJ Wingfield BD Wingfield MJ Crous PW 《Phytopathology》2007,97(7):825-834
ABSTRACT Dothistroma septosporum and D. pini are the two causal agents of Dothistroma needle blight of Pinus spp. in natural forests and plantations. Degenerate primers amplified portions of mating type genes (MAT1-1-1 and MAT1-2) and chromosome walking was applied to obtain the full-length genes in both species. The mating-type-specific primers designed in this study could distinguish between the morphologically similar D. pini and D. septosporum and between the different mating types of these species. Screening of isolates from global collections of D. septosporum showed that only MAT2 isolates are present in Australian and New Zealand collections, where only the asexual form of the fungus has been found. In contrast, both mating types of D. septosporum were present in collections from Canada and Europe, where the sexual state is known. Intriguingly, collections from South Africa and the United Kingdom, where the sexual state of the fungus is unknown, included both mating types. In D. pini, for which no teleomorph is known, both mating types were present in collections from the United States. These results provided new insights into the biology and global distribution of two of the world's most important pine pathogens and should facilitate management of the diseases caused by these fungi. 相似文献
946.
G?rel Nyman Stina Marntell Anna Edner Pia Funkquist Karin Morgan G?ran Hedenstierna 《Acta veterinaria Scandinavica》2009,51(1):22
Background
Sedation with α2-agonists in the horse is reported to be accompanied by impairment of arterial oxygenation. The present study was undertaken to investigate pulmonary gas exchange using the Multiple Inert Gas Elimination Technique (MIGET), during sedation with the α2-agonist detomidine alone and in combination with the opioid butorphanol.Methods
Seven Standardbred trotter horses aged 3–7 years and weighing 380–520 kg, were studied. The protocol consisted of three consecutive measurements; in the unsedated horse, after intravenous administration of detomidine (0.02 mg/kg) and after subsequent butorphanol administration (0.025 mg/kg). Pulmonary function and haemodynamic effects were investigated. The distribution of ventilation-perfusion ratios (VA/Q) was estimated with MIGET.Results
During detomidine sedation, arterial oxygen tension (PaO2) decreased (12.8 ± 0.7 to 10.8 ± 1.2 kPa) and arterial carbon dioxide tension (PaCO2) increased (5.9 ± 0.3 to 6.1 ± 0.2 kPa) compared to measurements in the unsedated horse. Mismatch between ventilation and perfusion in the lungs was evident, but no increase in intrapulmonary shunt could be detected. Respiratory rate and minute ventilation did not change. Heart rate and cardiac output decreased, while pulmonary and systemic blood pressure and vascular resistance increased. Addition of butorphanol resulted in a significant decrease in ventilation and increase in PaCO2. Alveolar-arterial oxygen content difference P(A-a)O2 remained impaired after butorphanol administration, the VA/Q distribution improved as the decreased ventilation and persistent low blood flow was well matched. Also after subsequent butorphanol no increase in intrapulmonary shunt was evident.Conclusion
The results of the present study suggest that both pulmonary and cardiovascular factors contribute to the impaired pulmonary gas exchange during detomidine and butorphanol sedation in the horse. 相似文献947.
Knuuttila A Uzcátegui N Kankkonen J Vapalahti O Kinnunen P 《Veterinary microbiology》2009,133(3):229-238
Aleutian mink disease virus (AMDV) is a parvovirus that causes an immune complex-mediated disease in minks. To gain a more detailed view of the molecular epidemiology of mink AMDV in Finland, we phylogenetically analysed 14 new Finnish strains from 5 farms and all 40 strains with corresponding sequences available in GenBank. A part of the major non-structural (NS1) protein gene was amplified and analysed phylogenetically. A rooted nucleotide tree was constructed using the maximum parsimony method. The strains described in this study showed 86-100% nucleotide identity and were nearly identical on each farm. The ratio of synonymous to non-synonymous substitutions was approximately 2.7, indicating a mild purifying selection. Phylogenetic analysis confirmed that AMDV strains form three groups (I-III), all of which contained Finnish strains. The tree inferred that the three lineages of AMDV have been introduced to Finland independently. The analysis suggested that AMDV strains do not cluster into genotypes based on geographical origin, year of isolation or pathogenicity. Based on these data, the molecular clock is not applicable to AMDV, and within this gene area no recombination was detected. 相似文献
948.
Andaluz A Moll X Abellán R Ventura R Carbó M Fresno L García F 《Veterinary journal (London, England : 1997)》2009,181(3):299-304
The purpose of this study was to evaluate plasma concentrations and pharmacokinetic parameters of buprenorphine in dogs following intravenous (IV) administration of clinical doses of the opioid. An IV bolus of 0.02 mg/kg buprenorphine was administered to six healthy Beagles and blood samples were collected through a jugular catheter before and at 1, 5, 10, 15, 20, 30 and 45 min, and 1, 2, 4, 6, 8 and 12 h after administration. Plasma buprenorphine concentrations, measured using a commercial radioimmunoassay (RIA), decreased following a three-exponential curve. The two distribution and the elimination half-lives were 2.9 ± 1.8 min, 16.5 ± 3.7 min, and 266.6 ± 82.0 min, respectively; the clearance was 329.6 ± 62.2 mL/min, and the steady state volume of distribution was 83.7 ± 26.5 L.The results demonstrated the feasibility of the RIA assay to analyse buprenorphine in dog plasma samples. Following IV administration buprenorphine showed a three-compartment kinetic profile, as has been described previously in humans, rabbits and cats. The relationship between plasma concentrations and dynamic effects in dogs remains to be established. 相似文献
949.
Costa C Tortosa R Vidal E Padilla D Torres JM Ferrer I Pumarola M Bassols A 《Veterinary journal (London, England : 1997)》2009,182(2):306-314
Bovine spongiform encephalopathy (BSE) is a transmissible spongiform encephalopathy characterised by accumulation of resistant prion protein (PrPBSE), neuronal loss, spongiosus and glial cell proliferation. In this study, properties of the extracellular matrix (ECM) were investigated in boTg110 transgenic mice over-expressing the bovine cellular prion protein (PrPc) and infected with BSE. Using immunohistochemistry with Wisteria floribunda agglutinin as a specific marker for perineuronal nets (PNNs) and antibodies against aggrecan and hyaluronic acid binding protein, loss of ECM was correlated with PrPBSE accumulation and activation of astrocytes and microglia. PrPBSE accumulation and glial cell activation were detected from the earliest stages of the disease and increased in the terminal stages. Decreases in PNNs, aggrecan and hyaluronic acid were observed only in the terminal stages and correlated with the distribution of PrPBSE and activated glial cells. This study suggests that the loss of PNNs, aggrecan and hyaluronic acid is a consequence of PrPBSE accumulation. Degradation of ECM in BSE may be due to secretion of degradative enzymes by activated glial cells. 相似文献
950.