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991.
992.
Sandra P. Tou DVM Bruce W. Keene DVM Piers C.A. Barker MD 《Journal of Veterinary Cardiology》2011,13(4):271-275
Pulmonary atresia and ventricular septal defect (PA-VSD) was diagnosed in a 2-year-old castrated male Terrier mix. Transthoracic echocardiography identified a large ventricular septal defect, overriding aorta and severe right ventricular hypertrophy. A main pulmonary artery could not be identified, consistent with pulmonary atresia or persistent truncus arteriosus. Transesophageal echocardiography and angiography confirmed PA-VSD with aortopulmonary collateral circulation arising from the descending thoracic aorta. This case report describes the antemortem diagnosis of the rare congenital defect PA-VSD in an adult dog. 相似文献
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Feldmann BM 《Journal of the American Veterinary Medical Association》2011,238(5):563; author reply 563
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Barry L. Perryman Teshome Shenkoru Leroy B. Bruce Hussein S. Hussein 《Strength and Conditioning Journal》2011,64(1):78-84
The effect of plant age on growing season chemical compositions and rumen fermentation characteristics was determined for three subspecies of big sagebrush: basin (Artemisia tridentata [Nutt.] subsp. tridentata), mountain (A. tridentata subsp. vaseyana [Rybd.] Beetle), and Wyoming (A. tridentata subsp. wyomingensis [Beetle and Young]). In vitro dry matter (IVDMD) and organic matter (IVOMD) disappearance, ammonia nitrogen (NH3N), and volatile fatty acid (VFA) content were determined at the end of two fermentation periods (24 h and 48 h) by combining rumen inocula with age-classified vegetative samples from each sagebrush subspecies. An additional one-way analysis of variance was performed to investigate potential differences among subspecies in IVDMD, IVOMD, total VFA, and NH3N following a 48-h fermentation period. Crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF), and acid detergent lignin (ADL) components were also compared among sagebrush subspecies. Age class responses were variable across the spectrum of sagebrush subspecies and response variables. Where plant age effects were indicated, the small numeric differences probably have little biological or ecological significance. Mountain sagebrush was lower in IVOMD and total VFA concentrations (P < 0.0001) than basin and Wyoming. NH3N concentration and CP were higher (P < 0.0001) in basin sagebrush than the other two subspecies, while Wyoming sagebrush was higher in NDF, ADF, and ADL than basin and mountain subspecies (P < 0.0001). NH3N concentration for all three subspecies was lower than the minimum level (20 mg · 100 mL?1) required for uninhibited rumen activity. Overall, this research questions the contention that older sagebrush plants offer less nutritional value than younger ones, at least for growing season conditions. The results also provide information that can be utilized in designing supplementation strategies for domestic animals on diets with characteristically high utilization of big sagebrush. 相似文献
999.
A study was conducted to assess the effect of temperature on infection and development of Plasmodiophora brassicae in the root cortex of Shanghai pak choy (Brassica rapa subsp. chinensis) and on subsequent clubroot severity. Ten-day-old seedlings were grown individually, inoculated with resting spores, and maintained in growth cabinets at 10, 15, 20, 25, and 30?C. Seedlings were harvested at 2-day intervals, starting 8 days after inoculation (DAI) and continuing until 42 DAI. Roots were assessed at 4-day intervals for the incidence of cortical infection and stage of infection (young plasmodia, mature plasmodia, and resting spores), at 2-day intervals for symptom development and clubroot severity, and at 8-day intervals for the number of spores per gram of gall. Temperature affected every stage of clubroot development. Cortical infection was highest and symptoms were observed earliest at 25?C, intermediate at 20 and 30?C, and lowest and latest at 15?C. No cortical infection or symptoms were observed at 42 DAI in plants grown at 10?C. A substantial delay in the development of the pathogen was observed at 15?C. Resting spores were first observed at 38 DAI in plants at 15?C, 26 DAI at 20 and 30?C, and 22 DAI at 25?C. The yield of resting spores from galls was higher in galls that developed at 20 to 30?C than those that developed at 15?C over 42 days of assessment. These results support the observation in companion studies that cool temperatures result in slower development of clubroot symptoms in brassica crops, and demonstrate that the temperature has a consistent pattern of effect throughout the life cycle of the pathogen. 相似文献
1000.
James W. Madgwick Jon S. West Rodger P. White Mikhail A. Semenov James A. Townsend Judith A. Turner Bruce D. L. Fitt 《European journal of plant pathology / European Foundation for Plant Pathology》2011,130(1):117-131
Climate change will affect both growth of agricultural crops and diseases that attack them but there has been little work
to study how its impacts on crop growth influence impacts on disease epidemics. This paper investigates how impacts of climate
change on wheat anthesis date will influence impacts on fusarium ear blight in UK mainland arable areas. A wheat growth model
was used for projections of anthesis dates, and a weather-based model was developed for use in projections of incidence of
fusarium ear blight in the UK. Daily weather data, generated for 14 sites in arable areas of the UK for a baseline (1960–1990)
scenario and for high and low CO2 emissions in the 2020s and 2050s, were used to project wheat anthesis dates and fusarium ear blight incidence for each site
for each climate change scenario. Incidence of fusarium ear blight was related to rainfall during anthesis and temperature
during the preceding 6 weeks. It was projected that, with climate change, wheat anthesis dates will be earlier and fusarium
ear blight epidemics will be more severe, especially in southern England, by the 2050s. These projections, made by combining
crop and disease models for different climate change scenarios, suggest that improved control of fusarium ear blight should
be a high priority in industry and government strategies for adaptation to climate change to ensure food security. 相似文献