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91.
REASONS FOR PERFORMING STUDY: Many racing jurisdictions monitor pre-race serum concentration of total carbon dioxide (TCO2) among racing horses. To our knowledge, factors influencing concentration of TCO2 among horses participating in racing have not been systematically evaluated and reported. OBJECTIVES: To determine if characteristics of horses and racing conditions routinely recorded were significantly associated with pre-race concentration of TCO2, while accounting for and estimating effects of trainer and horse. METHODS: Pre-race serum TCO2 concentrations from 5028 starts made by 2,349 horses trained by 287 trainers at 2 racetracks in California during 2005 were examined. Data regarding characteristics of starters and race conditions obtained from a commercial database were recorded for each start. Data were analysed using mixed-effects, with TCO2 concentration as the dependent variable, and trainer and horse nested within trainer as random effects. RESULTS: Sex, class and distance of race, frusemide administration and cloudy weather conditions were significantly (P<0.001) associated with pre-race TCO2 concentration. Horses that finished in the top 3 positions had values that were slightly (0.2 mmol/) but significantly (P<0.001) greater than horses not finishing in the top 3. There were significant effects of trainer on pre-race TCO2 concentration. CONCLUSIONS: A variety of factors may influence pre-race TCO2 concentration in horses. Horses with better performance tend to have higher pre-race TCO2 concentrations. POTENTIAL RELEVANCE: TCO2 concentration is associated with improved performance although the magnitude of effect was quite small. Regulatory programmes based on monitoring should consider the influence of other factors on TCO2 concentration. 相似文献
92.
Homoploid hybrid speciation in an extreme habitat 总被引:1,自引:0,他引:1
Gompert Z Fordyce JA Forister ML Shapiro AM Nice CC 《Science (New York, N.Y.)》2006,314(5807):1923-1925
According to theory, homoploid hybrid speciation, which is hybrid speciation without a change in chromosome number, is facilitated by adaptation to a novel or extreme habitat. Using molecular and ecological data, we found that the alpine-adapted butterflies in the genus Lycaeides are the product of hybrid speciation. The alpine populations possess a mosaic genome derived from both L. melissa and L. idas and are differentiated from and younger than their putative parental species. As predicted, adaptive traits may allow for persistence in the environmentally extreme alpine habitat and reproductively isolate these populations from their parental species. 相似文献
93.
Berge AC Sischo WM Craigmill AL 《Journal of the American Veterinary Medical Association》2006,229(8):1279-1281
OBJECTIVE: To determine the antimicrobial susceptibility of common respiratory tract pathogens from sheep and goats. DESIGN: Cross-sectional study. SAMPLE POPULATION: 41 respiratory tract isolates from sheep and 36 isolates from goats. PROCEDURES: Disk diffusion assay was used to determine antimicrobial susceptibility of isolates to amoxicillin-clavulanic acid, ceftiofur, ciprofloxacin, florfenicol, and tetracycline. Minimum inhibitory concentrations of florfenicol for these isolates were determined by use of the microbroth dilution technique. RESULTS: The most common isolates were Pasteurella multocida (n = 28) and Mannheimia haemolytica (39). All isolates were susceptible to amoxicillin-clavulanic acid, ceftiofur, ciprofloxacin, and florfenicol. Five percent (4/77) of isolates were resistant to tetracycline. CONCLUSIONS AND CLINICAL RELEVANCE: Susceptibility of respiratory tract pathogens isolated from sheep and goats to commonly used antimicrobial drugs in this study was high. Treatment of these species for bacterial respiratory tract disease is likely not complicated by antimicrobial resistance. 相似文献
94.
C Pöhlker KT Wiedemann B Sinha M Shiraiwa SS Gunthe M Smith H Su P Artaxo Q Chen Y Cheng W Elbert MK Gilles AL Kilcoyne RC Moffet M Weigand ST Martin U Pöschl MO Andreae 《Science (New York, N.Y.)》2012,337(6098):1075-1078
The fine particles serving as cloud condensation nuclei in pristine Amazonian rainforest air consist mostly of secondary organic aerosol. Their origin is enigmatic, however, because new particle formation in the atmosphere is not observed. Here, we show that the growth of organic aerosol particles can be initiated by potassium-salt-rich particles emitted by biota in the rainforest. These particles act as seeds for the condensation of low- or semi-volatile organic compounds from the atmospheric gas phase or multiphase oxidation of isoprene and terpenes. Our findings suggest that the primary emission of biogenic salt particles directly influences the number concentration of cloud condensation nuclei and affects the microphysics of cloud formation and precipitation over the rainforest. 相似文献
95.
BACKGROUND: Non-repellent insecticides, including fipronil and indoxacarb, are becoming increasingly important for soil treatments to manage the eastern subterranean termite, Reticulitermes flavipes (Kollar). The effects of these insecticides on termite walking and tunneling behavior could significantly reduce their efficacy against colonies. RESULTS: Groups of R. flavipes were exposed to several concentrations of commercial formulations of fipronil and indoxacarb, and the ability of treated termites to tunnel in soil and walk was assessed. Increasing insecticide concentration resulted in a reduction in the ability of R. flavipes to walk, tunnel and form tunnel branches; the importance of these effects on the use of non-repellent insecticides is discussed. CONCLUSION: Exposure of R. flavipes to 1, 10 or 50 mg L−1 of fipronil or 50, 100 or 200 mg L−1 of indoxacarb significantly reduced termite walking and tunneling and the number of tunnel branches. Distance walked (ca 73 mm) by untreated control termites did not change over time for at least 16 h after treatment; control termites formed ca 150 cm of tunnels with ca 40 branches. Copyright © 2012 Society of Chemical Industry 相似文献
96.
Frank H. Arthur 《Journal of pest science》2013,86(3):507-513
A series of experiments were conducted to evaluate residual efficacy of the insecticidal pyrrolle chlorfenapyr (Phantom®) on treated concrete for control of Tribolium castaneum (Herbst), assess development of progeny from exposed parental adults, and to determine if starvation before exposure with or without a flour food source increased susceptibility of adult T. castaneum and adult Tribolium confusum Jacqueline du Val to chlorfenapyr. No adults survived exposure on concrete treated with chlorfenapyr at the maximum label rate of 1.1 g active ingredient (AI)/m2, and no progeny were produced in bioassays conducted at 0–8 weeks posttreatment. In the second test, application rates were reduced, and bioassays were conducted at 27 and 32 °C. Adult survival and progeny production decreased as the application rate increased from 28 to 225 mg AI/m2, and survival and progeny production were generally lower at 32 °C than at 27 °C, but at higher rates survival was <1 %, and no progeny were produced. In the final test, adult T. castaneum and adult T. confusum were starved for 1–7 days and then exposed either with or without flour on concrete treated with 3.9 and 27.5 mg AI chlorfenapyr/m2. Mortality generally increased with starvation time, the presence of a food source led to decreased mortality at both application rates, and T. confusum was the more susceptible of the two species. Results show that chlorfenapyr could effectively control both species, but precise dosage levels need to be determined. Also, the presence of a food source greatly compromises adult control. 相似文献
97.
Wei Jiang Panpan Ye Chen-Tung Arthur Chen Kuiwu Wang Pengyuan Liu Shan He Xiaodan Wu Lishe Gan Ying Ye Bin Wu 《Marine drugs》2013,11(12):4761-4772
Two novel cyclodepsipeptides containing an unusual anthranilic acid dimer and a d-phenyllactic acid residues, clavatustides A (1) and B (2), were identified from cultured mycelia and broth of Aspergillus clavatus C2WU isolated from Xenograpsus testudinatus, which lives at extreme, toxic habitat around the sulphur-rich hydrothermal vents in Taiwan Kueishantao. This is the first example of cyclopeptides containing an anthranilic acid dimer in natural products, and the first report of microbial secondary metabolites from the hydrothermal vent crab. Clavatustides A (1) and B (2) suppressed the proliferation of hepatocellular carcinoma (HCC) cell lines (HepG2, SMMC-7721 and Bel-7402) in a dose-dependent manner, and induced an accumulation of HepG2 cells in G1 phase and reduction of cells in S phase. 相似文献
98.
Abstract Extract Recently, we reported on outbreaks of Leptospira interrogans serovar pomona infection in newly weaned lambs(1). It was suggested that wet environmental conditions played an important role in the pathogenesis of the disease in that class of sheep. This communication presents observations on another case of ovine leptospirosis, one that occurred under different circumstances, i.e. different season, age and environmental conditions. 相似文献
99.
Extract Several indicators of thrombosis and thrombolysis were measured in four groups of 16 pigs fed for 10 weeks on either a low fat basal ration or rations containing 10% anhydrous milkfat (AMF), 10% fish oil (MaxEPA), or 10% hydrogenated coconut oil (HCO). At the end of the feeding period, pigs on the three test fat/oil rations were subjected to balloon angioplasty of both femoral arteries. Thrombus size at the site of injury was measured both morphometrically and using autologous blood platelets labelled with 99Tc-HMPAO (technetium - “Deretec”). 相似文献
100.
Fiona Maunsell G Arthur Donovan 《Veterinary Clinics of North America: Food Animal Practice》2008,24(1):155-190
Biosecurity, biocontainment, and disease risk management on dairy replacement operations are time- and labor-intensive, planned programs. Oftentimes the value of these programs is realized only after disease is introduced to a facility or a disease outbreak occurs. There is no "one-plan-fits-all;" each plan must be tailored to meet the needs of management's goals and expectations and problems specific to a production enterprise or geographic region. A standard framework applicable to biosecurity programs includes: (1) hazard identification, (2) exposure assessment, (3) risk characterization, and (4) risk management. The discussion presented here helps lay the framework for development and implementation of biosecurity and risk-management programs within dairy replacement facilities. 相似文献