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991.
Peter A Robertson Tim Adriaens Xavier Lambin Aileen Mill Sugoto Roy Craig M Shuttleworth Mike Sutton‐Croft 《Pest management science》2017,73(2):273-279
Numerous examples exist of successful mammalian invasive alien species (IAS) eradications from small islands (<10 km2), but few from more extensive areas. We review 15 large‐scale removals (mean area 2627 km2) from Northern Europe since 1900, including edible dormouse, muskrat, coypu, Himalayan porcupine, Pallas' and grey squirrels and American mink, each primarily based on daily checking of static traps. Objectives included true eradication or complete removal to a buffer zone, as distinct from other programmes that involved local control to limit damage or spread. Twelve eradication/removal programmes (80%) were successful. Cost increased with and was best predicted by area, while the cost per unit area decreased; the number of individual animals removed did not add significantly to the model. Doubling the area controlled reduced cost per unit area by 10%, but there was no evidence that cost effectiveness had increased through time. Compared with small islands, larger‐scale programmes followed similar patterns of effort in relation to area. However, they brought challenges when defining boundaries and consequent uncertainties around costs, the definition of their objectives, confirmation of success and different considerations for managing recolonisation. Novel technologies or increased use of volunteers may reduce costs. Rapid response to new incursions is recommended as best practice rather than large‐scale control to reduce the environmental, financial and welfare costs. © 2016 Crown copyright. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. 相似文献
992.
993.
Coherent anti‐Stokes Raman scattering (CARS) spectroscopy in Caenorhabditis elegans and Globodera pallida: evidence for an ivermectin‐activated decrease in lipid stores 下载免费PDF全文
994.
Inge M Krijger Steven R Belmain Grant R Singleton Peter WG Groot Koerkamp Bastiaan G Meerburg 《Pest management science》2017,73(12):2397-2402
Current reactive pest management methods have serious drawbacks such as the heavy reliance on chemicals, emerging genetic rodenticide resistance and high secondary exposure risks. Rodent control needs to be based on pest species ecology and ethology to facilitate the development of ecologically based rodent management (EBRM). An important aspect of EBRM is a strong understanding of rodent pest species ecology, behaviour and spatiotemporal factors. Gaining insight into the behaviour of pest species is a key aspect of EBRM. The landscape of fear (LOF) is a mapping of the spatial variation in the foraging cost arising from the risk of predation, and reflects the levels of fear a prey species perceives at different locations within its home range. In practice, the LOF maps habitat use as a result of perceived fear, which shows where bait or traps are most likely to be encountered and used by rodents. Several studies have linked perceived predation risk of foraging animals with quitting‐harvest rates or giving‐up densities (GUDs). GUDs have been used to reflect foraging behaviour strategies of predator avoidance, but to our knowledge very few papers have directly used GUDs in relation to pest management strategies. An opportunity for rodent control strategies lies in the integration of the LOF of rodents in EBRM methodologies. Rodent management could be more efficient and effective by concentrating on those areas where rodents perceive the least levels of predation risk. © 2017 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. 相似文献
995.
996.
Suzanne Osorio Lujan Walid Habre Youssef Daali Zhaoxin Pan Peter W. Kronen 《Veterinary anaesthesia and analgesia》2017,44(3):665-675
Objective
To determine the absorption characteristics of fentanyl and buprenorphine administered transdermally in swine.Study design
A randomized comparative experimental trial.Animals
Twenty-four Yorkshire gilts weighing 27.8 ± 2.2 kg (mean ± standard deviation).Methods
Animals were randomly assigned to different doses of transdermal patches (TPs) of fentanyl (50 μg hour?1, 75 μg hour?1 and 100 μg hour?1) or buprenorphine (35 μg hour?1 and 70 μg hour?1), once or twice. Thirteen blood samples were obtained for each TP applied. Plasma concentrations were determined, and the area under the curve, peak serum concentration (Cmax) and time to Cmax were calculated.Results
Fentanyl: Cmax was observed at different time points: for the first TP application: 30 hours for 50 μg hour?1, 6 hours for 75 μg hour?1 and 100 μg hour?1 patches; and for the second TP application: 30 hours for 50 μg hour?1 and 36 hours for 75 μg hour?1 patches. Buprenorphine: serum concentrations were not detected for the 35 μg hour?1 patch; Cmax was observed at different times for the 70 μg hour?1 patch: 18 hours (n = 1), 24 hours (n = 3), 30 hours (n = 1) and 42 hours (n = 1) after application of the first patch and 12 hours after the second patch.Conclusions and clinical relevance
A relevant serum concentration obtained with fentanyl TP dosed at 75 μg hour?1 or 100 μg hour?1suggests that TPs could represent an analgesia option for laboratory pigs weighing 25–30 kg. As concentrations of buprenorphine were variable, this study does not support the use of buprenorphine TPs in pigs. Consecutive fentanyl or buprenorphine TPs did not provide reliable serum concentrations. Further pharmacokinetic studies and analgesiometric tests in swine are needed to confirm the clinical adequacy of TPs. 相似文献997.
Method comparison and generation of plasma biochemistry RIs for the White rhinoceros on a point‐of‐care and wet chemistry analyzer 下载免费PDF全文
998.
999.
Pedro Ah Shenga Peter Bomark Olof Broman Dick Sandberg 《Wood material science & engineering》2017,12(4):257-262
The sawmill industry is a very important link in the Mozambique forest products value chain, but the industry is characterized by undeveloped processing technology and high-volume export of almost unrefined logs. The low volume yield of sawn timber has been identified as a critical gap in the technological development of the industry. To improve the profitability of the industry, there is thus a need to develop methods and techniques that improve the yield. In this paper, different positioning of logs prior to sawing and the possibility of increasing the volume yield of crooked logs by bucking the logs before sawing have been studied. A computer simulation was used to study the cant-sawing and through-and-through sawing of the logs to determine the volume yield of sawn timber from the jambirre (Millettia stuhlmannii Taub.) and umbila (Pterocarpus angolensis DC.) species. The optimal position, i.e. the position of the log before sawing that gives the highest volume yield of sawn timber for a given sawing pattern when the positioning parameters, offset, skew and rotation, are considered gave a considerable higher volume yield than the horns-down position. By bucking very crooked logs and using the horns-down positioning before sawing, the volume yield can be of the same magnitude as that obtained by optimal positioning on full-length (un-bucked) logs. The bucking reduces the crook of the logs and hence increases the volume yield of sawn timber. 相似文献
1000.
Erik?V.?BachtiarEmail authorView authors OrcID profile Sergio?J.?Sanabria Johannes?P.?Mittig Peter?Niemz 《Wood Science and Technology》2017,51(1):47-67
Ultrasonic testing is a non-destructive testing method of choice for estimating the anisotropic elastic properties of wood materials. This method is reliable for estimating the Young’s and shear moduli. However, its applicability to Poisson’s ratios remains uncertain. On the other hand, despite their destructive nature, mechanical tests allow a direct measurement of all elastic properties including the Poisson’s ratios. In some cases (e.g. when assessing cultural heritage objects), destructive testing may not be an option. In this work, two types of hardwood walnut (Juglans regia L.) and cherry (Prunus avium L.), which often appear on cultural heritage objects, were tested using both ultrasonic and mechanical testing methods under four different moisture conditions below fibre saturation point. The results show that a higher moisture condition leads to a decrease in material elasticity. For walnut wood, their longitudinal Young’s modulus (\(E_{\rm L}\)) was reduced by 679 MPa under the compression load for a one per cent increase in moisture content. Moreover, three ultrasound data evaluation techniques, which differ in the way they incorporate the Poisson’s ratios (full stiffness inversion, simplified uncorrected, and simplified corrected), were used to estimate the Young’s moduli (E). The main goal is to obtain reliable material parameters using the ultrasound test. As a result, it is concluded that the chosen data evaluation method influences the accuracy of the calculated E. In a certain case, the simplified-corrected method, which requires only one specimen type, gave a closer agreement to mechanical tests (e.g. \(\Delta E_{\rm T}=6\,\%\) deviation on mechanical results). In another case, the full-stiffness-inversion method, which requires four specimen types, gave the best estimation (e.g. \(\Delta E_{\rm L}=2\,\%\)). In this corresponding direction, the simplified-corrected method can only partially reduce the overestimation of the simplified uncorrected from \(\Delta E_{\rm L}=47\) to 32 %. The variation of E produced by different evaluation procedures is due to the different correction factor values, which is a consequence of the variation in \(\nu\). 相似文献