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41.
Dan Laffoley John M. Baxter Diva J. Amon Duncan E.J. Currie Craig A. Downs Jason M. Hall‐Spencer Harriet Harden‐Davies Richard Page Chris P. Reid Callum M. Roberts Alex Rogers Thorsten Thiele Charles R.C. Sheppard Rashid U. Sumaila Lucy C. Woodall 《水产资源保护:海洋与淡水生态系统》2020,30(1):194-208
- The ocean crisis is urgent and central to human wellbeing and life on Earth; past and current activities are damaging the planet's main life support system for future generations. We are witnessing an increase in ocean heat, disturbance, acidification, bio‐invasions and nutrients, and reducing oxygen levels. Several of these act like ratchets: once detrimental or negative changes have occurred, they may lock in place and may not be reversible, especially at gross ecological and ocean process scales.
- Each change may represent a loss to humanity of resources, ecosystem function, oxygen production and species. The longer we pursue unsuitable actions, the more we close the path to recovery and better ocean health and greater benefits for humanity in the future.
- We stand at a critical juncture and have identified eight priority issues that need to be addressed in unison to help avert a potential ecological disaster in the global ocean. They form a purposely ambitious agenda for global governance and are aimed at informing decision‐makers at a high level. They should also be of interest to the general public.
- Of all the themes, the highest priority is to rigorously address global warming and limit surface temperature rise to 1.5°C by 2100, as warming is the pre‐eminent factor driving change in the ocean. The other themes are establishing a robust and comprehensive High Seas Treaty, enforcing existing standards for Marine Protected Areas and expanding their coverage, especially in terms of high levels of protection, adopting a precautionary pause on deep‐sea mining, ending overfishing and destructive fishing practices, radically reducing marine pollution, putting in place a financing mechanism for ocean management and protection, and lastly, scaling up science/data gathering and facilitating data sharing.
- By implementing all eight measures in unison, as a coordinated strategy, we can build resilience to climate change, help sustain fisheries productivity, particularly for low‐income countries dependent on fisheries, protect coasts (e.g. via soft‐engineering/habitat‐based approaches), promote mitigation (e.g. carbon storage) and enable improved adaptation to rapid global change.
42.
S M Gennari M C Bressan J R Rogero J M MacLean J L Duncan 《Veterinary parasitology》1991,38(2-3):163-172
This study was conducted to investigate the pathophysiology of Haemonchus placei infection in Friesian calves. Seven calves were divided into two groups, three uninfected calves (control group) and four infected animals. The latter group were infected orally with 500 H. placei larvae kg-1 body weight. Five weeks after infection they were all housed in metabolic crates and injected with 125I-bovine albumin. 51Cr-red cells and 59Fe-transferrin, to study albumin metabolism, erythrokinetics and ferrokinetics. The results showed that there was a significant reduction in the mean haematocrit values and reduced weight gains in the infected calves compared with the controls. There was also a change in the distribution of albumin from the extravascular to the intravascular pool and a significant increase in the plasma and blood volumes of infected calves although the blood and albumin loss via the gastrointestinal tract recorded in this study was similar in both groups. 相似文献
43.
Tropical Animal Health and Production - 相似文献
44.
Ethylenediamine tetraacetic acid disodium salt (EDTA) was found to be an important addition to anion exchange buffers in terms of the profile and amounts of eluted bovine serum proteins. Hydrogen ion concentration and buffer composition were important when different types of anion exchanger (DEAE 52 cellulose and QAE Sephadex A 50) were used for separation of bovine serum proteins as functional groups of the different anion exchangers did not behave similarly and were therefore not interchangeable. These findings applied to the purification of bovine serum IgG1 amounting to 15 to 25% of the total IgG1 was accomplished using QAE Sephadex A 50 anion exchange chromatography. This was followed by absorption of the IgG1 fraction with Staphylococcus aureus containing protein A to remove minor IgG2 contaminants and gel filtration to exclude traces of the third component of complement (C3). 相似文献
45.
Commercialization decisions and the economics of introduction 总被引:1,自引:0,他引:1
Summary A commercial horticultural industry that establishes plant-breeding nurseries for an exotic species throughout a regional
economy will expand until the marginal profit of the last nursery established is zero. However, a regional government concerned
with social welfare will take into account not only the profits of the horticultural industry but also any expected costs
of an accidental invasion. The latter costs will consist of the discounted expected social damages due to an increase in the
rate of invasion over time and the increase in expected damage cost per hectare caused by an additional nursery. A government
can employ an “introducers' pay” tax equal to the latter social costs to ensure that the plant breeding industry establishes
the optimal number of nurseries. We illustrate this outcome with the example of purple loosestrife (Lythrum salicaria) in North America. In the absence of any tax, the horticultural industry will establish n = 3528 nursery operations, and the expected damages from invasion are US$ 28.2 million per year. With the tax, only n = 300 nurseries are established but the expected damages from invasion are reduced to US$ 1.3 million per year. Although
profits for the horticultural industry are lower from the tax, the net gains in overall social welfare more than offset the
losses. Although these results are illustrative only, they show that the problem of plant invasives initiated by commercial
operations is amenable to standard economic analysis and solutions, such as implementation of an “introducers' pay tax”. 相似文献
46.
47.
Geoffrey?JonesEmail author Rachel?J.?Keedwell Alasdair?D.?L.?Noble Duncan?I.?Hedderley 《Journal of Agricultural, Biological & Environmental Statistics》2005,10(3):306-320
The motivation for this work was to investigate the possibility of accurately determining the age of a tern chick using easily
obtained body measurements. We describe the construction of a nonlinear multivariate hierarchical model for chick growth and
show how it can be estimated using Markov chain Monte Carlo techniques. A simple extension of the analysis allows for estimation
of the ages of unknown chicks. Posterior distributions of the unknown ages are derived, so that the accuracy of age determination
can be examined. We further extend our model and analysis to include the possibility that chicks fall into distinct groups
with different growth characteristics. The technique is illustrated using data on the weight and wing length of black-fronted
terns from the Ohau River, New Zealand. It is found that dating to within one day is possible, but only in some areas of the
data space. The concept of “braiding” of multivariate growth curves is introduced to explain the varying accuracy of age determination. 相似文献
48.
Worapa Seehalak Norihiko Tomooka Aree Waranyuwat Piyada Thipyapong Paisan Laosuwan Akito Kaga Duncan A. Vaughan 《Genetic Resources and Crop Evolution》2006,53(5):1043-1059
Thailand is a center of diversity for section Angulares of the Asian Vigna (genus Vigna subgenus Ceratotropis) and 4 Vigna species are cultivated in Thailand. Using newly collected wild and cultivated germplasm of Vigna from Thailand and outgroup accessions AFLP analysis was conducted to clarify genetic diversity and relationships. The results
suggest that cultivated V. umbellata and V. mungo evolved from wild relatives in a single domestication event. Vigna umbellata is poorly differentiated from its wild and weedy relatives compared to V. mungo. Results suggest northern Thailand and the neighboring Shan state, Myanmar, is the probable center of domestication for V. umbellata as wild accessions from this area and cultivated rice bean from a wide area in Asia are not greatly diverged. Vigna minima, V. tenuicaulis and V. exilis accessions in Thailand are well differentiated with considerable intra-specific variation. Vigna hirtella consists of two well differentiated subgroups, suggesting taxonomic revision may be necessary. Close genetic relationships
between V. radiata and V. grandiflora, and between V. mungo and V. trinervia are confirmed. Naturally growing V. mungo populations in northern Thailand appear to be true wild species as they are well differentiated from Indian wild and Thai
cultivated populations. The origin of naturally growing cowpea in Thailand needs to be further studied using a more comprehensive
set of materials. This study clarifies inter and intra-specific genetic diversity and inter species relationships of Thai
Vigna species. 相似文献
49.
Olivera L Canul RR Pereira-Pacheco F Cockburn J Soldani F McKenzie NH Duncan M Olvera-Novoa MA Grant G 《Journal of agricultural and food chemistry》2003,51(1):319-325
The nutritional and physiological effects of raw cowpea (Vigna unguiculata (L) Walp.) seed meal, protein isolate (globulins), or starch on the metabolism of young growing rats have been evaluated in 14-day trials. Wet and dry weight gain, feed conversion efficiency, and lipid and protein accretion were significantly reduced as a result of inclusion of seed meal, globulins, or starch in the diet, with growth retardation being most marked with the seed meal. The proportional weights of the small intestine and pancreas were increased by meal diets, and serum cholesterol levels were slightly reduced. The globulins and raw starch also increased relative small intestine weights but had no effect on the pancreas or serum constituents. The effects of cowpeas on rats appeared to be due primarily to the combined actions of globulins, resistant starches, protease inhibitors, and possibly fiber and non-starch polysaccharides on intestinal and systemic metabolism. 相似文献
50.