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41.
Virginie Laberge Sandrine Hugron Line Rochefort Monique Poulin 《Land Degradation \u0026amp; Development》2015,26(8):813-818
Vascular plants associated to natural peatland pools do not spontaneously colonize edges of man‐made pools in restored peatlands and have proven to be recalcitrant to the usual restoration techniques. The goal of this study was to evaluate the effect of the species used as a seedbed (Cladopodiella fluitans, Sphagnum cuspidatum, or Sphagnum magellanicum) and its developmental stage (established carpet or newly reintroduced fragments) on establishment success in the field of the seeds of four vascular species: Carex limosa, Carex magellanica, Carex oligosperma, and Scheuchzeria palustris. The germination rate was measured after one season and growth after two seasons. Seedbed composition and developmental stage had no effect on Carex, whereas the germination of S. palustris was higher on S. cuspidatum. Growth of vascular plants was slightly improved on S. magellanicum carpets and was lower on seedbeds of C. fluitans. Our results lead us to recommend seeding at the same time as bryophyte fragments are spread and fostering introduction of Sphagnum mosses, preferably to C. fluitans, around artificial pool edges. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
42.
J. C. Murdoch A. S. Foot M. J. Head Muriel C. Holdsworth Zena D. Hosking C. Line 《Grass and Forage Science》1959,14(4):247-252
The changes in chemical composition during haymaking, the loss of nutrients in the field and during storage, and the nutritive value of swath-cured and tripoded hay were compared. In good weather no advantage was gained by tripoding the hay. The nutritive value of the hays made by the two methods was similar and the loss of dry matter in the field slightly lower in the swath-cured hay. In a bad season, however, the nutrient loss in the swath-cured hay greatly exceeded that occurring in the tripoded hay and the starch equivalent, as shown by the results of digestibility trials, was markedly lower for the swath-cured. 相似文献
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Common causes of poor performance in horses include factors related to the horse, the rider and/or the saddle, and their interrelationships remain challenging to determine. Horse-related factors (such as thoracolumbar region pain and/or lameness), rider-related factors (such as crookedness, inability to ride in rhythm with the horse, inability to work the horse in a correct frame to improve core strength and muscular support of the thoracolumbar spine of the horse), and saddle-related factors (such as poor fit causing focal areas of increased pressure) may all contribute to poor performance to varying degrees.Knowledge of the horse–saddle–rider interaction is limited. Traditionally, saddle fit has been evaluated in standing horses, but it is now possible to measure the force and pressure at the interface between the saddle and the horse dynamically. The purpose of this review is critically to discuss available evidence of the interaction between the horse, the rider and the saddle, highlighting not only what is known, but also what is not known. 相似文献
46.
In the results from a previously reported uniformity trial on pasture evaluation, there appeared to be systematic areal changes in the crude fibre and crude protein percentages of the herbage. These trends have been illustrated by the calculation of quadratic contours and the possible relationships of the changes to local soil differences, moisture percentages and copse shelter effects have been investigated. 相似文献
47.
Several methods were evaluated for collecting fecal and intestinal samples from wild birds found near broiler chicken houses. A few intestinal samples and cloacal swabs were obtained from European starlings and house sparrows. Most of the samples collected consisted of wild bird droppings found on or near the houses. Samples were collected from each of four farms of a broiler integrator during a grow-out cycle: a cycle in the summer for farm A, fall for farm B, and spring, summer, fall, and winter for farms C and D. Of the 25 wild bird intestinal and fecal samples collected from a broiler house on farm A during a grow-out cycle in July-August 1997, 24% were positive for Salmonella spp., 4% for Campylobacter jejuni, and 28% for Clostridium perfringens. Of the nine fecal samples collected from broiler house B in a grow-out cycle in September-November 1997, 33% were positive for Salmonella spp., 11% for C. jejuni, and 22% for C. perfringens. For farms C and D, of the 23 samples collected in March-April 1998, 0 were positive for Salmonella spp., 11% for C. jejuni, and 52% for C. perfringens; of 27 samples collected in June-July 1998, 4% were positive for Salmonella spp., 0 for C. jejuni, and 13% for C. perfringens; of 24 samples collected in August-October 1998, 14% were positive for Salmonella spp., 5% for C. jejuni, and 4% for C. perfringens; of 14 samples collected December 1998-January 1999, 0 were positive for Salmonella, 50% for C. jejuni, and 14% for C. perfringens. The incidence of these bacterial enteropathogens in wild birds near the broiler chicken houses suggests that wild birds that gain entry to poultry grow-out houses have the potential to transmit these pathogens to poultry. 相似文献
48.
Seroprevalence in Chickens against Campylobacter jejuni Flagellar Capping Protein (FliD) in Selected Areas of the United States
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H.‐Y. Yeh K. L. Hiett J. E. Line J. F. Jagne D. C. Lauer 《Zoonoses and public health》2016,63(4):265-270
Campylobacter jejuni is a causative pathogen of human acute bacterial gastroenteritis. Infected poultry products are regarded as a major source for human C. jejuni infection. The flagellar capping protein (FliD) is highly conserved among C. jejuni strains/isolates and is antigenic as analysed by immunoblot. In this study, we used the FliD protein as a probe to survey the prevalence of C. jejuni antibodies in chickens from two areas in the United States. A total of 394 samples were tested. Sera from layer breeders of 44–52 weeks of age tested 100% positive, while 4‐ to 6‐week broilers from 22 premises showed 7–100% positivity. These results demonstrate that anti‐FliD antibodies were prevalent in the poultry population in the areas of serum samples collected. 相似文献
49.
Albert Kjartan Dagbjartarson Imsland Bjrn Roth Line Bach Christensen Sten Ivar Siikavuopio Atle Foss 《Aquaculture Research》2020,51(10):4022-4029
Possible effects of short‐term starvation on flesh quality in Arctic charr were studied in spring (March) and summer (August). Groups of juvenile Arctic charr (mean weight March 536 g ± 24; August 461 g ± 15 SEM) were starved for 1, 2 and 4 weeks (March) and 1, 2 and 3 (August). After each starvation period, the fish were slaughtered, and flesh samples collected in order to investigate quality and textural properties in the different experimental groups. Starvation had a positive effect on flesh quality giving firmer texture and lower gaping scores. Starved fish had lower cathepsin activity at slaughter, and a similar difference was seen one‐week post mortem. The results showed that the effect of starvation period was seasonally dependent. Starvation had a larger effect in summer, where a three‐week starvation resulted in firmer texture, whereas this was not seen during spring. 相似文献
50.
Johan Asplund Eva Hustoft Line Nybakken Mikael Ohlson Marit H. Lie 《Scandinavian Journal of Forest Research》2018,33(4):332-337
European beech Fagus sylvatica and Norway spruce Picea abies are economically and ecologically important forest trees in large parts of Europe. Today, the beech forest reaches its northern distribution limit in south-eastern Norway and it is expected to expand northwards due to climate warming. This expansion will likely result in fundamental ecosystem changes. To increase our knowledge about the competitive balance between spruce and beech, we have investigated how beech and spruce litter affect spruce seedling emergence, growth and uptake of C and N. We did this in a seed-sowing experiment that included litter layer removal as well as reciprocal transplantations of litter layers between spruce and beech forests. Our results show that spruce seedling emergence was significantly impaired by both litter layer types, and especially so by the beech litter layer in the beech forest. The low seedling emergence in beech forests is concurrent with their lower light availability. 相似文献