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601.
In order to provide recommendations for future cropping systems with regard to the necessary minimum of pesticide use, a long-term field trial at the field site in Dahnsdorf of the Julius Kühn-Institute was conducted in the years 2004 to 2016 to investigate possible reduction of pesticides, taking into account the general principles of integrated pest management (Strategies to reduce the use of plant protection products). Two winter wheats (WW1 and WW2) were part of the crop rotation with six components and different quality classes (A wheat (WW1) and E wheat (WW2)) and resistance levels to important wheat pathogens. In all years, herbicides and fungicides were needed to control weeds and fungal pathogens due to the excess of the control threshold. Insecticides were only necessary in two years. When considering the treatment frequency index (TFI), the mean overall TFI varied with 2.6 in WW1 and 3.5 in WW2, but was significantly lower compared to practice. There were also differences in the mean fungicide TFI of the two crop rotation elements with 1.1 in WW1 and 1.6 in WW2 due to their different resistance level to important fungal pathogens. The same is true with regard to the herbicide TFI with of 1.1 in WW1 and 1.3 in WW2. The treatments in the strategies 2, 3 and 4 mostly resulted in significantly higher yields compared to the non-chemical strategy 1, which can be attributed to the strong weed and fungal infestations in strategy 1 and the good efficacy of the used plant protection products. The tended differences between strategy 2 with a situation-related application rate and the 25 and 50% reduced application rates in strategies 3 and 4, respectively, were not significant. A reduced application rate showed no negative long-term effects on weed emergence even after 13 years, but increased emergence numbers in strategies with reduced herbicide use. The results show that plant protection products savings are possible without significantly reducing yields. However, this requires a high level of human resources for monitoring and scoring the consistent observance of the principles of integrated pest management, such as the consideration of good crop rotation, the cultivation of resistant cultivars and the optimally coordinated treatments after the control threshold has been exceeded. 相似文献
602.
603.
Wattrang E McNeilly F Allan GM Greko C Fossum C Wallgren P 《Veterinary microbiology》2002,86(4):281-293
An outbreak of exudative epidermitis (EE) among piglets in a Swedish SPF-herd initiated a survey for indications as to the cause of disease.The herd was established by caesarean section and has been closed to all new animal material, with the exception of semen for artificial insemination (AI). The study comprised serum samples from the SPF-herd over a 10-year period (n=109) and a close monitoring of animals in the herd during the period after the EE outbreak. Serum samples from conventional boars at the AI-station servicing the herd were also included (n=9). All serum samples were tested for antibodies to porcine circovirus-2 (PCV-2). In addition, 3-week-old piglets from three litters (n=24) farrowed close after the initial EE outbreak were closely monitored for clinical signs of skin disease, sampled for Staphylococcus hyicus, tested for antibodies to porcine parvovirus and in sequentially collected serum samples tested for interferon-alpha (IFN-alpha) and interleukin-6.The PVC-2 serology showed that animals in the herd were sero-negative at least until 2 months prior to the EE outbreak. During the period close after the EE outbreak the animals showed varying levels of antibodies to PCV-2 but all the tested animals had sero-converted 4 months later. The AI boars were also sero-positive to PCV-2 at the time of the EE outbreak. Animals in the SPF-herd remained sero-positive to PCV-2 during the following 7 years. In the monitored litters, one piglet had clinical EE and 15 piglets displayed defined erythemas on the abdomen. Fourteen of the piglets also had IFN-alpha in serum on one or more occasions during the study, indicating viral activity among the animals. S. hyicus was isolated from all of the piglets from the earliest sampling point (3 days of age) and onwards, irrespective of clinical signs. PCV-2 was isolated from lymph node tissue collected from one of the EE affected pigs.Further, increases in the number of stillborn piglets, small litters (<6 piglets) and repeat breeders could be correlated to the time of PCV-2 sero-conversion. Coincidence of active viral infection and sero-conversion to PCV-2 points to the virus as the cause of the EE outbreak and reproductive disturbances. 相似文献
604.
María Botero Omary Christina Fong Jeffrey Rothschild Patrick Finney 《Cereal Chemistry》2012,89(1):1-14
There are a growing number of individuals diagnosed with food allergies and intolerances. Gluten, in particular, is avoided by many individuals because of celiac disease, gluten intolerance, and gluten ataxia. Individuals with allergies, intolerances, or both follow strict diets, but there is concern that these individuals may be at risk of several nutrient deficiencies, including decreased calcium, iron, B vitamins, and fiber. To prevent deficiencies, alternative sources of these nutrients must be provided. Gluten‐free cereals and pseudocereals such as amaranth, buckwheat, corn, millet, rice, sorghum, and quinoa can be excellent sources of vitamins, minerals, fiber, and other important nutrients. Germination of these edible seeds has been shown to further increase nutrient content and to reduce antinutrients. Their use to naturally fortify and enrich gluten‐free foods has great potential. Although there are many benefits to germinated seeds in food, more research must be done to improve texture and sensory properties to gain wider consumer acceptance. A review of germination of gluten‐free cereals and pseudocereals and its effect on their nutritional profile is presented. 相似文献