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461.
Earle-Richardson G Fulmer S Jenkins P Mason C Bresee C May J 《Journal of agricultural safety and health》2004,10(3):163-176
Although back, neck, and shoulder strains are common among migrant and seasonal orchard workers, little data currently exist regarding the ergonomic factors contributing to this problem. We adapted Posture-Activities-Tools-Handling (PATH) instruments and methods for ergonomic job analysis of apple harvest work in three New York orchards, and used the resulting protocol to quantify hazardous activities, loads, and postures. Using a prototype developed previously, we trained twelve contract orchard observers with classroom training and supervised orchard practice. The PATH data were then collected on 14 orchard workers over four days (2,900 observations). Mean coefficients of variation ranged from a low of 0.212 (standing leg neutral) to a high of 0.603 (trunk moderate flexion). Most frequently observed activities were: picking (62.9%), placing and moving apples in the bag (8. 7%), and walking (8.1%). Weight bearing (>10 lb, >4.54 kg) was observed 78.5% of the time throughout a range of activities. Apple harvest work is comparable with other ergonomically high-risk occupations. Future research should focus on low-cost interventions that reduce load and awkward postures. 相似文献
462.
ABSTRACTAims: To determine the presence of infection and co-infection of Plasmodium lineages in introduced birds at translocation sites for the North Island saddleback (Philesturnus rufusater), to investigate their role as Plasmodium spp. reservoirs.Methods: Blood samples were collected from introduced bird species, with a special focus on blackbirds (Turdus merula) and song thrushes (Turdus philomelos), at six locations in the North Island of New Zealand that were the origin, or translocation sites, for North Island saddleback. Where available, blood smears were examined, and blood samples were tested using nested PCR with subsequent sequence analysis, for the presence of Plasmodium spp.Results: Of the 55 samples tested using PCR analysis, 39 (71%) were positive for Plasmodium spp., and 28/40 (62%) blood smears were positive for Plasmodium spp. Overall, 31 blood samples were from blackbirds with 28/31 (90%) samples positive for Plasmodium spp. Six distinct avian Plasmodium lineages were identified, including three cosmopolitan lineages; Plasmodium vaughani SYAT05 was detected in 16 samples, Plasmodium matutinum Linn1 in 10 samples and Plasmodium elongatum GRW6 in eight samples. Mixed infections with more than one lineage were detected in 12 samples. Samples from two Australian magpies (Gymnorhina tibicen) were positive for Plasmodium. sp. lineage MYNA02, previously not identified in New Zealand.Conclusions and clinical relevance: This is the first report from New Zealand in which specific Plasmodium spp. mixed infections have been found in introduced birds. Co-infections with several cosmopolitan Plasmodium lineages were identified, as well as the first report in New Zealand of an exotic avian Plasmodium sp. lineage, in Australian magpies. Whilst the role of introduced birds in maintaining and spreading pathogenic avian malaria in New Zealand is unclear, there is a potential infection risk to native birds, especially where distributions overlap. 相似文献
463.
Journal of Plant Diseases and Protection - Pine wood nematode (PWN), Bursaphelenchus xylophilus, causes pine wilt disease (PWD) in Pinus species given suitable climatic conditions. A model was run... 相似文献
464.
DM Hassler IE Dammasch P Lemaire P Brekke W Curdt HE Mason JC Vial K Wilhelm 《Science (New York, N.Y.)》1999,283(5403):810-813
Observations of outflow velocities in coronal holes (regions of open coronal magnetic field) have recently been obtained with the Solar and Heliospheric Observatory (SOHO) spacecraft. Velocity maps of Ne7+ from its bright resonance line at 770 angstroms, formed at the base of the corona, show a relationship between outflow velocity and chromospheric magnetic network structure, suggesting that the solar wind is rooted at its base to this structure, emanating from localized regions along boundaries and boundary intersections of magnetic network cells. This apparent relation to the chromospheric magnetic network and the relatively large outflow velocity signatures will improve understanding of the complex structure and dynamics at the base of the corona and the source region of the solar wind. 相似文献
465.
J R Jenkins 《Veterinary Clinics of North America: Exotic Animal Practice》1999,2(1):143-51, vii
The feeding recommendations for the pet or house rabbit include grass hay fed ad libitum, dark leafy green vegetables fed at one cup per 5 pounds of body weight, and a maximum of 1 cup of high fiber pellets per 5 pounds of body weight. These recommendations are based on the feeding behavior, anatomy, and gastrointestinal physiology of the rabbit. Feeding this diet reduces the occurrence of common gastrointestinal tract disease in the house rabbit. This article reviews the feeding behavior, anatomy, and gastrointestinal physiology of the rabbit. 相似文献
466.
The unusual hard x-ray burster GRO J1744-28 recently discovered by the Compton Gamma-Ray Observatory can be modeled as a strange star with a dipolar magnetic field of =10(11) gauss. According to this model, when the accreted mass of the star exceeds some critical mass, its crust breaks, resulting in the conversion of the accreted matter into strange matter and a release of energy. Subsequently, a fireball forms and expands relativistically outward. The expanding fireball interacts with the surrounding interstellar medium, causing its kinetic energy to be radiated in shock waves and producing a burst of x-ray radiation. The burst energy, duration, interval, and spectrum derived from such a model are consistent with the observations of GRO J1744-28. 相似文献
467.
In situ measurements of organics, meteoritic material, mercury, and other elements in aerosols at 5 to 19 kilometers 总被引:1,自引:0,他引:1
In situ measurements of the chemical composition of individual aerosol particles at altitudes between 5 and 19 kilometers reveal that upper tropospheric aerosols often contained more organic material than sulfate. Although stratospheric aerosols primarily consisted of sulfuric acid and water, many also contained meteoritic material. Just above the tropopause, small amounts of mercury were found in over half of the aerosol particles that were analyzed. Overall, there was tremendous variety in aerosol composition. One measure of this diversity is that at least 45 elements were detected in aerosol particles. These results have wide implications for the complexity of aerosol sources and chemistry. They also offer possibilities for understanding the transport of atmospheric aerosols. 相似文献
468.
U.S. Babu P.L. Wiesenfeld M.Y. Jenkins 《Plant foods for human nutrition (Dordrecht, Netherlands)》1998,53(2):169-174
The impact of rosemary extract on splenic mononuclear cell proliferation was determined. Weanling male Sprague-Dawley rats were fed diets containing 0, 100, 200 or 400 ppm rosemary extract or 400 ppm butylated hydroxytoluene (BHT) in combinatiion with 10 or 20% casein enriched diets for 8 weeks. Splenic mononuclear cells were isolated from these animals and mitogenic response to Concanavalin A (Con A), Phytohemagglutinin (PHA) and lipopolysaccharide was determined. Con A and PHA-stimulated proliferation of spleen cells from rats fed 10% casein and 200 ppm rosemary extract was significantly higher than that of cells from the corresponding control animals. However, other levels of rosemary at 10% dietary casein or rosemary at any concentration fed along with 20% dietary casein had no impact on the mitogenic stimulation of splenic mononuclear cells. Thus, these results suggest that the use of rosemary might not have a generalized immunoenhancing effect, and will probably be effective in some stressed conditions, such as protein or antioxidant deficiency. 相似文献
469.
470.
Andrew W. Claridge Douglas J. Mills Rob Hunt David J. Jenkins Josh Bean 《Forest Ecology and Management》2009
Satellite tracking was used to follow the movements of a problematic top-order carnivore, the wild dog (Canis lupus dingo, C. lupus familiaris and their hybrids), in contiguous forested landscapes in south-eastern mainland Australia. Home range sizes of wild dogs were much larger than previously determined using conventional telemetry methods, averaging 10,000 ha with a maximum size of 59,000 ha over approximate 3-month periods. Wild dogs at sites with high abundance of kangaroos, wallabies and rabbits had smaller areas of occupancy than did dogs at sites with low availability of these preys. Despite mostly large home ranges, tracked animals were loyal to publicly-owned tenure and there were few instances where individuals moved large distances on to adjacent private tenure. Instead, movement behaviours of most tracked animals were characterised by repeated short distance forays, often at acute angles from previous locations. Consequently, home ranges were stable and otherwise well defined. Analysis of DNA from our study animals indicated that most individuals were of ‘dingo’ ancestry, but otherwise considered hybrids because of the presence of domestic dog genes. Only two of 24 animals could be considered as ‘pure’ dingo. Contemporary wild dog management demarcates lands where control is or is not undertaken, with the latter notionally acting to ‘conserve’ dingoes. Due to the large scale of movement of animals, existing control efforts likely impact over a greater area than previously suspected. Furthermore, our genetic findings suggest that conservation of dingoes in south-eastern mainland Australia is difficult to achieve. A modified approach to wild dog management is needed, taking account of the extent of range of individual animals and the existing genetic characteristics of populations. 相似文献