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61.
62.
This study provides empirical evidence on the link between economic growth and nutrition transition in two emerging economies, China and Russia. Both countries have experienced rising average incomes, accompanied by an increasing rate of nutrition-related chronic diseases in recent years. Given the regional heterogeneity between these two countries, we analyze the extent to which income growth as a major driver of nutrition transition has a significant effect on the consumption of different food aggregates and how these effects differ between Chinese and Russian consumers. Our results indicate that with increasing household incomes over time the demand for carbohydrates decreases, while the demand for meat and dairy products, as well as fruits increases. This is a development generally known as nutrition transition. Further, we estimate a Quadratic Almost Ideal Demand System(QUAIDS) for nine different food aggregates for China and Russia. Our results indicate that in both countries all food aggregates have positive expenditure elasticities and are thus normal goods. Moreover, our results indicate that in 2008/2009 meat is still a luxury good in China yet a necessity good in Russia. For 2009, the highest own-price elasticities in China are found for non-meat protein sources and dairy products. Within the meat group, beef, poultry and mutton have the highest price elasticities in China. In Russia, the milk and dairy group, together with the vegetable group, is the most price-elastic food group in 2008. In line with the definition of a nutrition transition, our overall results underscore the finding that income growth in China and Russia tends to increase the demand for animal-based products much stronger than, for example, the demand for carbohydrates. Despite being a positive signal for problems of malnutrition in rural China, this trend of increasing meat consumption might further increase the incidence of chronic diseases in urban areas since there is convincing scientific evidence that increasing meat consumption, especially red and processed meat, is associated with an increased risk of chronic diseases. 相似文献
63.
The emergence and spread of infectious diseases in mid-latitudes, so far mainly observed in the tropics, considerably increase under the current situation of climate change. A recent example is the Usutu virus (USUV) outbreak in Austria. USUV is closely related to the West Nile virus in the U.S. and caused mass mortalities mainly of blackbirds (Turdus merula). The USUV flavivirus persists in a natural transmission cycle between vectors (mosquitoes) and host reservoirs (birds) and leads - once endemic in a population - to periodic outbreaks. In an epidemic model to explain the USUV dynamics in Austria 2001-2005, USUV dynamics were mainly determined by an interaction of bird immunity and environmental temperature. To investigate future scenarios, we entered temperature predictions from five global climate models into the USUV model and also considered four different climate-warming scenarios defined by the I ntergovernmental Panel on Climate Change, IPCC (20 different model-scenario combinations). We downscaled the 20 time series of predicted temperatures (through the year 2100) to represent the region around Vienna. Our simulations predict that USUV will persist in the host population after the epidemic peak observed in 2003. USUV-specific annual blackbird-mortality time series predict that the outbreak frequency increases successively from the beginning to the end of the century. Simulations of worst-case scenarios result in an endemic equilibrium with a decline of the blackbird population of about 24%. Additionally we calculated the annually averaged basic reproduction number for the period 1901-2100. The latter depict that undetected major outbreaks before 2000 were unlikely, whereas it is likely that the USUV becomes endemic after 2040. 相似文献
64.
Häsler B Hernandez JA Reist M Sager H Steiner-Moret C Staubli D Stärk KD Gottstein B 《Veterinary parasitology》2006,137(3-4):222-230
We conducted a longitudinal study to follow-up the anti-Neospora caninum serologic status in 30 initially seropositive and 83 initially seronegative cows during their pregnancy. Study cows were blood-sampled every other month during pregnancy until parturition. Blood serum samples were screened for anti-N. caninum antibodies by ELISA. Cows that seroconverted were re-tested by immunoblot as a confirmation test. Among 30 seropositive cows, 28 cows remained seropositive during the whole pregnancy, whereas 2 cows transiently tested negative at least once during pregnancy. Among 83 seronegative cows, 82 cows remained seronegative and 1 cow tested positive three times during the sixth, eighth and last month of pregnancy. As only 2 out of 30 seropositive animals and 1 out of 83 animals changed their serologic status during pregnancy, the study results indicate that there is only a minor temporal instability of anti-N. caninum antibody reactivity in adult cattle. 相似文献
65.
Flavobacterium columnare and F. psychrophilum are important pathogens of the aquaculture industry, and thus disinfection of aquaculture systems and equipment is essential for disease control. This study examined commercially available compounds in vitro for their ability to eliminate these two species of Flavobacterium from the water. The compounds evaluated included Clorox, ethanol, Roccal, Lysol, iodine, formalin, Chloramine-T, glutaraldehyde, potassium permanganate, sodium chloride, and Virkon Aquatic. In this study, 70% ethanol, 50% ethanol, Clorox, Roccal, Lysol, iodine, glutaraldehyde, Chloramine-T, and Virkon Aquatic reduced the number of bacteria of both species to zero within one minute of contact time. Formalin and 30% ethanol also killed both species of bacteria, but required a longer contact time. Potassium permanganate killed F. columnare within one minute, but did not reduce the numbers of F. psychrophilum even after one hour of contact time. Sodium chloride was not effective. 相似文献
66.
Priming: it’s all the world to induced disease resistance 总被引:2,自引:0,他引:2
Katharina Goellner Uwe Conrath 《European journal of plant pathology / European Foundation for Plant Pathology》2008,121(3):233-242
After infection by a necrotising pathogen, colonisation of the roots with certain beneficial microbes, or after treatment
with various chemicals, many plants establish a unique physiological situation that is called the ‘primed’ state of the plant.
In the primed condition, plants are able to ‘recall’ the previous infection, root colonisation or chemical treatment. As a
consequence, primed plants respond more rapidly and/or effectively when re-exposed to biotic or abiotic stress, a feature
that is frequently associated with enhanced disease resistance. Though priming has been known as a component of induced resistance
for a long time, most progress in the understanding of the phenomenon has been made over the past few years. Here we summarize
the current knowledge of priming and its relevance for plant protection in the field. 相似文献
67.
Potential for simultaneous improvement of grain and biomass yield in Central European winter triticale germplasm 总被引:1,自引:0,他引:1
Manje GowdaVolker Hahn Jochen C. ReifC. Friedrich H. Longin Katharina AlheitHans P. Maurer 《Field Crops Research》2011,121(1):153-157
Winter triticale, an abundant biomass source for producing biogas in Central Europe, has been bred until now for increased grain yield but not for early biomass yield. Therefore, our objectives were to assess the feasibility of breeding triticale for simultaneous improvement of early biomass and grain yield as well as to predict the early biomass yield using an index of traits measured at maturity stage. A representative sample of 100 triticale lines was evaluated in Experiment I at four locations in Germany. Traits were measured at two growth stages (early dough and full maturity). Genetic variances were significantly different from zero for all traits. The correlated response for early biomass yield estimated from grain yield (0.53) was high, which points to the efficiency of indirect selection. A multiple regression model was developed to predict early biomass yield. The reliability of the model was confirmed in an independent Experiment II with 49 lines. The calibration model explained 55% of total variation for early biomass yield. This clearly underlines that at least during earlier stages of selection, field testing can be carried out for grain yield and related traits to select potential genotypes with high biomass yield based on the developed regression model. 相似文献
68.
Hematologic and plasma chemistry RIs for cultured Striped catfish (Pangasius hypophthalmus) in recirculating aquaculture systems 下载免费PDF全文
69.
Edwardsiellosis is an important bacterial infection of freshwater and marine fishes. Edwardsiella ictaluri causes enteric septicemia of catfish, and E. tarda causes emphysematous putrefactive disease of catfish and fish gangrene in various species; these diseases have considerable economic effects on the aquaculture industry. In addition, E. tarda is an important zoonotic pathogen. Thus, the reduction or elimination of these pathogens from an aquarium or aquaculture facility is imperative. This study examined a variety of commercially available chemicals for their ability to reduce or eliminate E. ictaluri and E. tarda from the aquatic environment. The various concentrations of chemicals were tested in vitro in microcentrifuge tubes with a known concentration of bacteria at room temperature. In this study, ethyl alcohol (30, 50, or 70%), benzyl-4-chlorophenol/phenylphenol (1%), sodium hypochlorite (50, 100, 200, or 50,000 mg/L), n-alkyl dimethyl benzyl ammonium chloride (1:256), povidone iodine (50 or 100 mg/L), glutaraldehyde (2%), and potassium peroxymonosulfate/sodium chloride (1%) were effective disinfectants, as each reduced or eliminated the number of detectable organisms within 1 min of contact time. However, neither Chloramine-T (15 mg/L) nor formalin (250 mg/L) substantially reduced bacterial counts even after 60 min of contact time. 相似文献
70.
Katharina Dehnen-Schmutz Ottmar Holdenrieder Mike J. Jeger Marco Pautasso 《Scientia Horticulturae》2010,125(1):1-15
The horticultural sector has seen much structural change both nationally and internationally over the last decades, but the implications for plant health have been neglected. We review in the context of the risk of emerging plant diseases recent developments including the movement towards a global horticultural market, the rise of the horticultural industry of many developing countries, and the economic integration of the European Union. North America is typically well ahead of other regions in economic developments, and in horticulture this is shown for example by the growing importance of Mexican growers. Asia is rapidly catching up also in horticulture, with China and India becoming key producers. Australia and New Zealand show the impact of change in horticulture extension services. The Eastern enlargement of the EU is having profound influences on fruit and vegetable growers both in the new and in the old member countries. Similar developments are taking place in South America and Africa. In all continents, there is a general trend towards fewer and larger horticultural growers, an increasing role of supermarkets and a concentration of the retail pathways. These developments have consequences for the control of plant pathogens and invasive species. Technical issues seem to be of lesser consequence in terms of structural change compared with labour and trade aspects. However, examples can be found where technical innovations have opened up new opportunities or provided solutions to pressing problems, as can be seen in the hardy nursery stock and ornamental industry in the UK. Future technical, economic and social impacts on the sector are likely to play a key role for securing a diverse and reliable food supply for the still expanding world's population. Recent advances in modelling disease spread in complex networks representing trade pathways should be used to target control of introductions of new plant pathogens. There is a need for more long-term research on how structural change in the horticultural sector will affect and be affected by climate change. 相似文献