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961.
962.
963.
Petra Sim
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Ron Lowe Valentina Granziera Alessio Pierini Filippo Torrigiani George Lubas 《Veterinary and comparative oncology》2020,18(3):428-432
Non‐tonsillar squamous cell carcinoma (ntSCC) is a common and locally aggressive oral tumour in dogs. The treatments of choice are currently surgery and radiotherapy. Electrochemotherapy (ECT) is a local ablative anti‐tumour technique using electric pulses to enhance the intracellular diffusion of cytotoxic drugs. The aim was to retrospectively evaluate the outcome of patients with oral ntSCC treated with ECT. Twelve dogs with ntSCC were retrospectively enrolled. ECT was combined with IV bleomycin (15 000 UI/m2) alone in 11 cases and post‐surgery in 1. Parameters considered were: tumour site and size, electroporation parameters, response rate (complete remission [CR], partial remission [PR]), median survival time (MST), recurrence rate (RR), median disease‐free interval (DFI) and treatment toxicity (6‐point scale). Median tumour size was 1.65 cm (range 0.3‐8.0 cm) and the response rate was 90.9% (10/11; 8 CR and 2 PR). Two dogs underwent a second ECT. MST for dogs dead with tumour (n = 2) was 110 days and for dogs dead without tumour (n = 3) was 831 days. Among five surviving dogs, one experienced tumour recurrence and four were in CR. Results from two dogs were analysed separately. Overall RR was 27.3%. DFI and MST for dogs with recurrence were 50 and 115 days, respectively. Treatment toxicity was very low. We noticed that all dogs with tumours smaller than 1‐2 cm achieved CR without recurrence suggesting a favourable prognosis when using ECT. ECT for canine ntSCC could be considered a valid treatment option especially for smaller tumours, but a larger caseload would be needed to confirm this statement. 相似文献
964.
Eberhart-Phillips D Haeussler PJ Freymueller JT Frankel AD Rubin CM Craw P Ratchkovski NA Anderson G Carver GA Crone AJ Dawson TE Fletcher H Hansen R Harp EL Harris RA Hill DP Hreinsdóttir S Jibson RW Jones LM Kayen R Keefer DK Larsen CF Moran SC Personius SF Plafker G Sherrod B Sieh K Sitar N Wallace WK 《Science (New York, N.Y.)》2003,300(5622):1113-1118
The MW (moment magnitude) 7.9 Denali fault earthquake on 3 November 2002 was associated with 340 kilometers of surface rupture and was the largest strike-slip earthquake in North America in almost 150 years. It illuminates earthquake mechanics and hazards of large strike-slip faults. It began with thrusting on the previously unrecognized Susitna Glacier fault, continued with right-slip on the Denali fault, then took a right step and continued with right-slip on the Totschunda fault. There is good correlation between geologically observed and geophysically inferred moment release. The earthquake produced unusually strong distal effects in the rupture propagation direction, including triggered seismicity. 相似文献
965.
An object spinning at the surface of a liquid creates a chiral vortex. If the spinning object is itself chiral, its shape modifies the characteristics of the vortex; interactions between that vortex and other vortices then depend on the chirality of the objects that produce them. This paper describes the aggregation of millimeter-sized, chiral magnetized plates floating at a liquid-air interface and rotating under the influence of a rotating external magnetic field. This external field confines all the plates at densities that cause the vortices they generate to interact strongly. For one set of plates investigated, plates of one chirality attract one another, and plates of the other chirality repel other plates of both chiralities. 相似文献
966.
Igwe David Okeh Ihearahu Onyinye Constance Osano Anne Adhiambo Acquaah George Ude George Nkem 《Genetic Resources and Crop Evolution》2022,69(1):49-70
Genetic Resources and Crop Evolution - Assessing the effectiveness of different molecular markers is essential for identification of appropriate ones for crop improvement and conservation, hence,... 相似文献
967.
The acute toxicity of un-ionized ammonia, nitrite, and nitrate to 50–76-mm fingerling channel catfish (Ictalurus punctatus) was investigated using a static bioassay system at 22, 26 and 30°C. The 96-h LC50 values at 30°C for un-ionized ammonia, nitrite, and nitrate were 3.8, 44, and 6 200 mg/l. 相似文献
968.
George H. Robertson Ann E. Blechl William J. Hurkman Olin D. Anderson Trung K. Cao Charlene K. Tanaka Kay S. Gregorski William J. Orts 《Cereal Chemistry》2013,90(1):1-12
Wheat protein is a technologically challenging substrate for food and nonfood applications because of its compositional diversity and susceptibility to denaturation. Genetic modification could be used to create cultivars capable of producing more uniform or focused and novel protein compositions targeted to nonfood uses. These lines could serve as expression systems for specific high‐molecular‐weight (HMW) protein polymers and would be new crops leading to more diverse agricultural opportunities. However, fundamental changes to the molecular architecture in such wheat seeds could also result in separation and processing issues, such that conventional methods of protein enrichment may need modification or even reinvention. Enriched gluten protein fractions were prepared from Bobwhite lines modified to overproduce HMW glutenin subunits Dx5 and/or Dy10. These lines serve as experimental models to test various approaches that may be taken for protein polymer enrichment. However, conventional wheat gluten enrichment based on the glutomatic as a small model of industrial methods was incapable of producing enrichment for any of the tested meal or flour, including that from the non‐transformed parent Bobwhite. Mixing in the mixograph or farinograph failed to produce standard patterns for whole kernel meal and straight‐run flour, and the normal cohesiveness of dough expected from these devices was not observed. Microscopy of stained dough samples revealed severely limited formation of normal protein networks, a capability crucial to conventional separation technology. Particle size analysis of whole kernel meal revealed a higher resistance to milling for the altered lines. Higher drying rates, lower farinograph moisture absorption, and increased thermal transition temperatures were observed. These data suggested that the native architecture of these new forms was more tightly constructed with reduced capacity for alteration by hydration and input of mechanical energy. An alternative enrichment method featuring solvation in SDS and precipitation in acetone produced coagulated (Bobwhite) or partially coagulated protein (transgenic lines producing Dx5 or Dy10) enriched to 78–85% protein with high yield. 相似文献
969.
Jeremy Rayner Michael Howlett Jeremy Wilson Benjamin Cashore George Hoberg 《Forest Policy and Economics》2001,2(3-4)
Policy analysis has usually been organized around the concept of the policy sector, which has served as the fundamental unit for analyzing policy change. The emergence of well-defined and institutionalized issue subsectors, however, has called the utility of a purely sectoral analysis of policy dynamics into question. Utilizing evidence from a case study of forest policy development in British Columbia, Canada, in the 1990s, this article suggests that understanding policy change in complex sectors such as forestry requires a more nuanced conceptualization and analysis of sector–subsectoral relationships than exists in the present literature. The article develops the notion of critical subsectors, capable of blocking or enabling overall levels and directions of sectoral policy change, as an essential tool required to understand policy dynamics. 相似文献
970.
A George RA Shah R Sharma P Palta SK Singla RS Manik MS Chauhan 《Reproduction in domestic animals》2011,46(3):444-447
Parthenogenetic activation using zona‐free oocytes offers an alternative model that could be applied to develop protocols for the activation of reconstructed embryos for cloning. The aim of this study was to compare the efficacy of different methods for the activation of zona‐free buffalo oocytes in terms of their effects on the developmental competence of parthenogenetic embryos. The effects of zona removal on parthenogenetic activation and in vitro developmental competence of metaphase II oocytes were also examined. All activation methods were followed by incubation of 2 mm 6‐dimethylaminopurine (6‐DMAP) for 4 h. Out of three different pulse strengths (1.2, 2.1 or 3.3 kV/cm) used, 2.1 kV/cm resulted in the highest blastocyst rate (25.3%). On comparing different chemical agents and electric pulse, highest blastocyst rate was observed for calcium ionophore (CaI) (28.6%) followed by ethanol (25.0%), electric pulse (22.5%) and combined CaI and ethanol treatment (16.7%) although differences among them were not significant. Furthermore, a significantly reduced developmental potential was observed in zona‐free oocytes when compared to zona‐intact ones up to the blastocyst stage (44.3% vs 27.1%). In conclusion, zona‐free buffalo oocytes can be successfully activated for parthenogenetic development using chemical or electrical stimulation. Out of different agents examined, CaI followed by 6‐DMAP resulted in the highest blastocyst rate. 相似文献