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11.
12.
利用 Northern 杂交和核酸保护分析(RPA)检测了番茄ACC 合成酶(ACS)和 ACC氧化酶(ACO)基因家族在番茄突变体Epinastics (Epi)果实中的表达特性,同时测定了Epi果实自动催化乙烯合成系统的特性⒚EPI等位基因的突变诱导了LEACS2 和LEACO1 两个基因的过表达,这是Epi果实的乙烯过表达的主要成因⒚EPI突变同时显著抑制了LEACS4 和 LEACO3 的表达强度⒚这些结果初步鉴别了这两个基因家族在番茄果实上表达的各个成员的转录调节途径⒚同时表明,番茄单基因乙烯反应突变体是研究ACS和ACO基因家族各成员转录调节特性的一种有用工具⒚ 相似文献
13.
Nottingham RM Hosking BC Schmid HR Strehlau G Junquera P 《Australian veterinary journal》2001,79(1):51-57
OBJECTIVE: To assess a ready-to-use formulation of dicyclanil to prevent blowfly strike on coarse and fine woolled sheep under New Zealand conditions. DESIGN: Randomized clinical field trials. PROCEDURE: In a first field trial, coarse wooled sheep treated with a ready-to-use, 5% dicyclanil formulation were compared with untreated control sheep for up to 21 weeks. In a second field trial, fine woolled sheep, treated with the same dicyclanil formulation, were compared with untreated sheep for up to 19 weeks. Efficacy was assessed by calculating the aggregated cumulative strike rate. RESULTS: For trial 1 (coarse woolled sheep) the aggregated cumulative strike rate at the end of the trial at week 21 after treatment reached 3.9% and 19.1% for treated and untreated sheep, respectively. For the treated animals the aggregated cumulative strike rate reached the 1% and 2% benchmarks between weeks 11 and 12. For trial 2 (fine woolled sheep) the aggregated cumulative strike rate at the end of the trial at week 19 reached 0.6% and 7.5% for treated and untreated sheep, respectively. Wool length at the time of application did not substantially influence the efficacy of dicyclanil. CONCLUSION: Under New Zealand field conditions, a ready-to-use 5% spray-on formulation of dicyclanil protected coarse woolled sheep for at least 12 weeks and fine woolled sheep for at least 19 weeks. 相似文献
14.
James T Rothwell Thomas J Burnett Kristina Hacket Roderick Chevis L Barry Lowe 《Pest management science》2001,57(11):993-999
The depletion of zeta‐cypermethrin residues in bovine tissues and milk was studied. Beef cattle were treated three times at 3‐week intervals with 1 ml 10 kg?1 body weight of a 25 g litre?1 or 50 g litre?1 pour‐on formulation (2.5 and 5.0 mg zeta‐cypermethrin kg?1 body weight) or 100 mg kg?1 spray to simulate a likely worst‐case treatment regime. Friesian and Jersey dairy cows were treated once with 2.5 mg zeta‐cypermethrin kg?1 in a pour‐on formulation. Muscle, liver and kidney residue concentrations were generally less than the limit of detection (LOD = 0.01 mg kg?1). Residues in renal‐fat and back‐fat samples from animals treated with 2.5 mg kg?1 all exceeded the limit of quantitation (LOQ = 0.05 mg kg?1), peaking at 10 days after treatment. Only two of five kidney fat samples were above the LOQ after 34 days, but none of the back‐fat samples exceeded the LOQ at 28 days after treatment. Following spray treatments, fat residues were detectable in some animals but were below the LOQ at all sampling intervals. Zeta‐cypermethrin was quantifiable (LOQ = 0.01 mg kg?1) in only one whole‐milk sample from the Friesian cows (0.015 mg kg?1, 2 days after treatment). In whole milk from Jersey cows, the mean concentration of zeta‐cypermethrin peaked 1 day after treatment, at 0.015 mg kg?1, and the highest individual sample concentration was 0.025 mg kg?1 at 3 days after treatment. Residues in milk were not quantifiable beginning 4 days after treatment. The mean concentrations of zeta‐cypermethrin in milk fat from Friesian and Jersey cows peaked two days after treatment at 0.197 mg kg?1 and 0.377 mg kg?1, respectively, and the highest individual sample concentrations were 2 days after treatment at 0.47 mg kg?1 and 0.98 mg kg?1, respectively. © 2001 Society of Chemical Industry 相似文献
15.
The mode of action of a nitromethylene heterocycle (NMH) insecticide was studied by patch–clamp techniques using cockroach embryonic cultures as an experimental model. Under whole-cell recordings, this compound elicited inward currents resembling those induced by O-acetylcholine (ACh). The reversal potentials for both ACh and the NMH were similar, suggesting that the inward currents induced by both were carried by the same species of ion. Pharmacological investigations of NMH-induced responses revealed that the insecticidal action of this compound is exerted through agonistic action at the nicotinic acetylcholine receptor. Single-channel studies were also performed to study the interaction of NMH with the nicotinic-receptor-coupled ion channel. 相似文献
16.
Amounts of DDT and its breakdown products were determined in soil in an apple orchard in Herefordshire. Samples were taken for a number of years (1972–79) after use of the insecticide in the orchard had ceased in 1969. The results were compared with those obtained in an investigation of the same orchard in 1968. From 1968 to 1979, soil residues of pp′-DDT, p′--DDT and pp′--TDE decreased gradually whereas those of pp′--DDE increased, and there were linear relationships between log (concentration) and time. The calculated time for 50% decrease in concentration (Dt50) was 11.7 years for pp′--DDT, 3.3 years for pp′--TDE and 7.1 years for op′--DDT; the time for doubling the concentration for pp′--DDE was 9.1 years. Regression analysis on the two major components (pp′--DDT+pp′--DDE) indicated that the total amount (2.7 mg kg?1) was not decreasing with time. It was concluded that during a post-spray era, the breakdown of pp′--DDT to pp′--DDE was a significant feature of the persistence of DDT, and that, in contrast to the findings of other workers who sampled when DDT was being used, there were no losses by volatilisation. There was an exponential decrease in the amount of DDT residues with increasing soil depth and approximately 90% was found in the top 10 cm of the undisturbed soil profile. 相似文献
17.
Tick-infested adult cattle were hand sprayed with solutions containing 178 or 250 mg amitraz litre?1, prepared from a miscible oil concentrate formulation. Both concentrations achieved clearance of infestation within 7 h of spraying. All stages of tick, collected from both sprayings, subsequently died with the exception of two engorged nymphs, which moulted successfully, and six half-fully engorged females, which all laid small batches of eggs. The eggs from the ticks treated at the higher rate failed to hatch. Expulsion of adult Rhipicephalus appendiculatus, applied daily to a single bovine which had been sprayed once at the higher rate, ceased on the 11th day after spraying. All ticks expelled from the animal died within 24 h. First feeding on the animal was visible on day-13 and fully engorged females were first observed 18 days after spraying. 相似文献
18.
Brumbaugh GW Herman JD Clancy JS Burden KI Barry T Simpson RB López HS 《American journal of veterinary research》2002,63(1):36-41
OBJECTIVE: To evaluate chemotactic, phagocytic, and bactericidal activities of bovine and porcine alveolar macrophages (AM) exposed to tilmicosin. ANIMALS: 12 healthy calves and 12 healthy pigs. PROCEDURES: Lungs were obtained immediately after euthanasia; AM were collected by means of bronchoalveolar lavage and density gradient centrifugation. Chemotactic activity was evaluated by exposing AM to lipopolysaccharide or macrophage inhibitory peptide during incubation with tilmicosin. Phagocytic activity was evaluated by incubating AM with tilmicosin for 24 hours and then with tilmicosin-resistant Salmonella serotype Typhimurium. Bactericidal activity was evaluated by incubating AM with tilmicosin (0, 10, or 20 microg/ml for bovine AM; 0 or 10 microg/ml or 10 microg/ml but washed free of tilmicosin for porcine AM) and then with Mannheimia haemolytica (bovine AM) or with Actinobacillus pleuropneumoniae or Pasteurella multocida (porcine AM). RESULTS: Tilmicosin had no significant effects on chemotactic or phagocytic activities of bovine or porcine AM. The time-course of bactericidal activity was best described by polynomial equations. Time to cessation of bacterial growth and area under the time versus bacterial number curve were significantly affected by incubation of AM with tilmicosin. CONCLUSIONS AND CLINICAL RELEVANCE: Results show that bactericidal activity of bovine and porcine AM was enhanced by tilmicosin, but not in proportion to the reported ability of AM to concentrate tilmicosin intracellularly. With or without exposure to tilmicosin, the time-course of bactericidal activity of bovine AM against M haemolytica and of porcine AM against A pleuropneumoniae or P multocida was too complex to be reduced to a simple linear equation. 相似文献
19.
Barry M Taylor J Woods JP 《The Canadian veterinary journal. La revue veterinaire canadienne》2002,43(5):369-371
A domestic shorthair cat was presented for lethargy and ataxia. Clinical findings included an abdominal mass, lumbosacral pain, ataxia. Aspirates from the liver and lymph nodes revealed intracellular, negative-staining rods. Treatment for presumptive mycobacterium infection was unsuccessful and the cat was euthanized. Disseminated Mycobacterium avium was confirmed on culture. 相似文献
20.
Johnson B Gorman NT Hird JF Wadsworth DE Wells JA Dyson SJ Bleby J 《The Veterinary record》2002,151(8):247; author reply 247