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Objective To evaluate the effect of the number of days exposure to a prepartum transition diet on mineral, energy and protein metabolism in dairy cows. Design A prospective cohort study. Procedures The prepartum transition diet consisted of ryegrass pasture, cereal hay, grain, grain by-product, protein meals, BioChlor®, rumen modifiers, minerals and vitamins and contained 13.9% crude protein, 10.0 MJ metabolisable energy/kg and a dietary cation anion difference of −35 meq/kg dry matter. Forty cows were bled bi-weekly from their introduction to the prepartum transition diet until day 35 of lactation. Blood samples were submitted for estimation of a range of metabolites. Cubic smoothed splines were fitted to scatterplots of metabolite concentration as a function of day relative to calving and the area under the curve (AUC) was calculated. Linear regression modelling determined the effect of days exposed, age, body condition score (BSC) and calving day on AUC. Results The prepartum AUC of blood phosphorus and beta-hydroxybutyrate increased and the AUC of blood calcium and cholesterol decreased with increasing days exposed to the diet. The postpartum AUC of beta-hydroxybutyrate and non-esterified fatty acids decreased with increasing days exposed but increased with days exposed × age and days exposed × BCS, respectively. The AUC of other metabolites did not vary significantly with number of days exposed. Conclusions Increasing exposure to the prepartum diet significantly altered the AUC of blood metabolites associated with mineral, energy and protein metabolism in ways consistent with improvements in production and reproduction previously reported and the result suggests links between energy, protein and skeletal metabolism.  相似文献   
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Suspected cases of poisoning of honeybees by agricultural pesticides are investigated by the Ministry of Agriculture, Fisheries and Food (in England and Wales) and the Scottish Office Agriculture and Fisheries Department (in Scotland). Studies include field visits to sites where bee mortality is recorded, examination of dead bees for disease, and analysis for the presence of pesticide residues. This paper reviews the results of these investigations for the period 1981–1991. Pesticide poisoning is diagnosed from the detection of residues in dead bees, through interpretation in relation to the median lethal dose (LD50), and ‘subsequent residue level’ (SRL) determined from laboratory studies in which bees were exposed to one LD50 dose. Overall, an annual average of 50 incidents were confirmed as due to pesticide poisoning, involving 30 pesticide active ingredients during the 1981–1991 period. In England and Wales, the principal hazards were caused by misuse of the insecticide triazophos on oilseed rape, a problem that has been reduced to low levels during the 1980s, and by dimethoate use on a variety of arable crops. In Scotland there were fewer incidents, most of which were associated with use of fenitrothion on raspberries, and gamma-HCH on oilseed rape. Opportunities for reducing the risks of poisoning, and for refining the investigation of suspected incidents, are discussed.  相似文献   
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We describe the movement of cattle throughout Argentina in 2005. Details of farm-to-farm and farm-to-slaughter movements of cattle were obtained from the Sanitary Management System database (Sistema de Gestión Sanitaria, SGS), maintained by the National Service for Agrifood Health and Quality (SENASA). Movements were described at the regional and district level in terms of frequency, the number of stock transported, the district of origin and destination and Euclidean distance traveled. Social network analysis was used to characterize the connections made between regions and districts as a result of cattle movement transactions, and to show how these characteristics might influence disease spread. Throughout 2005 a total of 1.3 million movement events involving 32 million head of cattle (equivalent to approximately 57% of the national herd) were recorded in the SGS database. The greatest number of farm-to-farm movements occurred from April to June whereas numbers of farm-to-slaughter movement events were relatively constant throughout the year. Throughout 2005 there was a 1.1-1.6-fold increase in the number of farm-to-farm movements of cattle during April-June, compared with other times of the year. District in-degree and out-degree scores varied by season, with higher maximum scores during the autumn and winter compared with summer and spring. Districts with high in-degree scores were concentrated in the Finishing region of the country whereas districts with high out-degree scores were concentrated not only in the Finishing region but also in Mesopotamia, eastern Border and southern Central regions. Although movements of cattle from the Border region tended not to be mediated via markets, the small number of districts in this area with relatively high out-degree scores is a cause for concern as they have the potential to distribute infectious disease widely, in the event of an incursion.  相似文献   
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SnakeMap is a national cloud-based, veterinary snakebite registry. It was designed to prospectively collect data of the clinical circumstances and temporospatial information on cases of snake envenomation in dogs and cats. We herein introduce the project and summarise the data from the first 4 years of SnakeMap. The registry is a veterinary community-based online database allowing case entry from veterinary hospitals across Australia. Registry data comprise hospital characteristics, patient characteristics, envenoming snake type, treatment and outcome variables, including time and geolocation of the snake bite. We present summative information on select key variables from the SnakeMap registry (1 July 2015 to 30 June 2019). Twenty-eight hospitals from 6 states/territories entered 624 cases into the registry, including 419 dogs (67%) and 205 cats (33%). Bite time was available in 216 animals of which 90 (42%) were reported to be bitten in the 3 hours between 03:00 pm and 05:59 pm; median bite to presentation interval was 60 (interquartile range [IQR] 30, 211) minutes in dogs and 95 (IQR 41, 238) minutes in cats. Bites occurred in the owner's yard in 356 dogs (85%) and 53 cats (26%). A snake venom detection kit was used in 172 cases (28%) and antivenom was administered in 523 cases (85%). Most animals (n = 534, 88%) survived to discharge (median hospitalisation of 25 [IQR 16, 62] hours). SnakeMap effectively collects relevant clinical data from dogs and cats with presumed snake bite and provides locally specific information on the epidemiology of snake envenomation in small animals.  相似文献   
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Seminole (FL282 or B4469-7) is a new potato variety, named and released by the Research and Farm Departments of Frito-Lay, Inc. Its medium-early tubers are round to oblong with smooth, light cream-buff skin color. The eyes are shallow and pink. It was selected on the Research Farm, Rhinelander, Wisconsin from family line B4469, one of 399 family lines received from the National Potato Breeding Program, Beltsville, Maryland. Tested for its reaction to Verticillium wilt, it was one of the most resistant among 1,190 seedlings. It proved superior to many named and numbered varieties in specific gravity and chip color. In Alabama, Seminole produced relatively high yields of tubers with unusually high specific gravity. Tests in Florida and North Carolina gave similar results. In the South, Seminole is usually 7–10 days earlier than Sebago, and produces higher yields of tubers with higher specific gravity. Unlike Sebago, its tubers separate readily from the vines preventing losses in mechanical harvesting.  相似文献   
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