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671.
Bjørn O. Eggum Inge Hansen Torben Larsen 《Plant foods for human nutrition (Dordrecht, Netherlands)》1989,39(1):13-21
Chemical analyses and balance trials with rats of 17 foods showed marked differences in protein quality. According to anin vitro procedure true protein digestibility was high (around 90%). The same was also the case for thein vivo values with the exception of two legumes, beans and chick peas, which were digested to a markedly lower degree when compared to thein vitro values. The assumed reason for this is discussed. Due to extensive differences in the amino acid composition of the 17 samples BV varied considerably with the lowest value (45.5) of rice-wheat gluten breakfast cereal. Energy digestibility was generally high. Amino acid digestibility determinedin vivo followed the pattern of the corresponding protein digestibility, although marked differences occurred from one amino acid to another in the same food. 相似文献
672.
Bacteria belonging to the Vibrionaceae family are widespread in the marine environment. Today, 128 species of vibrios are known. Several of them are infamous for their pathogenicity or symbiotic relationships. Despite their ability to interact with eukaryotes, the vibrios are greatly underexplored for their ability to produce bioactive secondary metabolites and studies have been limited to only a few species. Most of the compounds isolated from vibrios so far are non-ribosomal peptides or hybrids thereof, with examples of N-containing compounds produced independent of nonribosomal peptide synthetases (NRPS). Though covering a limited chemical space, vibrios produce compounds with attractive biological activities, including antibacterial, anticancer, and antivirulence activities. This review highlights some of the most interesting structures from this group of bacteria. Many compounds found in vibrios have also been isolated from other distantly related bacteria. This cosmopolitan occurrence of metabolites indicates a high incidence of horizontal gene transfer, which raises interesting questions concerning the ecological function of some of these molecules. This account underlines the pending potential for exploring new bacterial sources of bioactive compounds and the challenges related to their investigation. 相似文献
673.
674.
Hanne Christine Bertram Bent Ole Petersen Jens ? Duus Mogens Larsen Birgitte-Marie L Raun Niels Bastian Kristensen 《Acta veterinaria Scandinavica》2009,51(1):25
Background
It is unknown which metabolites are responsible for propylene glycol (PG)-induced toxicosis, and a better understanding of the underlying mechanisms explaining incidences of abnormal behaviour of dairy cows fed PG is therefore needed.Methods
The study included three cows of which one developed PG toxicosis. In order to investigate how the metabolism of PG differed in the cow developing toxicosis, proton nuclear magnetic resonance (NMR) spectroscopy was applied on ruminal fluids and blood plasma samples obtained before and after feeding with PG.Results
PG toxicosis was characterized by dyspnea and ruminal atony upon intake of concentrate containing PG. The oxygen saturation of arterial blood haemoglobin and the oxygen pressure in arterial blood decreased along with the appearance of the clinical symptoms. NMR revealed differences in plasma and ruminal content of several metabolites between the cow responding abnormally to PG and the two control cows.Conclusion
It is concluded that PG-toxicosis is likely caused by pulmonary vasoconstriction, but no unusual metabolites directly related to induction of this condition could be detected in the plasma or the ruminal fluid. 相似文献675.
C. Epe C. Holst R. Koopmann T. Schnieder M. Larsen G. von Samson-Himmelstjerna 《Veterinary parasitology》2009
The aim of this study was to investigate the effect of the nematophagous fungus Duddingtonia flagrans applied orally to small ruminants in a field study in Germany. 相似文献
676.
A captive 5-yr-old castrated male Rocky Mountain wapiti (Cervus elaphus nelsoni) developed stranguria. Rectal palpation and physical examination indicated urethral obstruction that was subsequently relieved by urethrostomy and required only minimal aftercare. The wapiti was able to urinate freely after surgery; however, the obstruction recurred 27 mo later. Urethral catheterization relieved the second obstruction, which was caused by a large calculus composed of calcium carbonate and magnesium carbonate. Urolithiasis may have been associated with a diet high in calcium, and urethral obstruction may have been associated with castration at an early age. The wapiti continued to urinate freely 9 mo after relief of the second obstruction and 3 yr after the initial surgery. 相似文献
677.
Steen Larsen 《Acta veterinaria Scandinavica》1967,8(4):347
Three cases of gastritis in sows due to the stomach worm Hyostrongylus rubidus are described. This disease has not previously been reported from the Scandinavian countries.Diffuse gastritis and extreme emaciation were the essential findings at necropsy in all 3 cases.In 2 animals the gastric changes consisted of diffuse nodular hyperplasia of the mucosa. In the third case similar hyperplastic changes were present, but these were largely obscured by a superimposed extensive diphtheresis of the mucosa.The gastric changes in cases of hyostrongylosis reported in the literature and the conceptions regarding their pathogenesis are reviewed and discussed.In the sow with diphtheroid gastritis large numbers of Balantidium coli, in addition to H. rubidus, were present in the altered stomach mucosa. It is assumed that the gastritis due to H. rubidus has resulted in gastric hypochlorhydria thus creating an environment of sufficiently low acidity for ingested Balantidium spp. to live and multiply. Whether this parasite has participated in the development of the gastric diphtheresis is impossible to ascertain. 相似文献
678.
In milk samples from 1520 heifers and 542 dams the αsl-, β- and x-casein types and the β-lactoglobulin components, A and B, were determined simultaneously by means of electrophoresis in thin starchurea-gels.The theory of inheritance advanced within each system from previous investigations was confirmed. Family data on the transmission of the two x-casein components A and B are given (Table 3). The frequencies of the controlling genes in Danish cattle were computed for each of the systems (Table 2).With traditional starch-gel-electrophoresis, four components, termed A, B, G and D, could be demonstrated in the β-lactoglobulin (Figs. 3 and 4). The four components are presumed to be controlled by four allele genes.The αsl-, β- and ϰ-casein phenotypes were not independently distributed and the segregation of casein types among offspring from bulls heterozygotic in two or three casein type-systems strongly suggests that the genetic variations of the αsl-, β- and ϰ-casein are controlled by genes at a single locus. Then, a minimum of 8 alleles may account for the phenotypes observed among 521 Danish cows (Table 6).Linkage of less than five per cent recombination could be excluded between the casein types and the β-lactoglobulin types. 相似文献
679.
Aloysius T.M. van Helmond Lars O. Mortensen Kristian S. Plet‐Hansen Clara Ulrich Coby L. Needle Daniel Oesterwind Lotte Kindt‐Larsen Thomas Catchpole Stephen Mangi Christopher Zimmermann Hans Jakob Olesen Nick Bailey Heidrikur Bergsson Jrgen Dalskov Jon Elson Malo Hosken Lisa Peterson Howard McElderry Jon Ruiz Johanna P. Pierre Claude Dykstra Jan Jaap Poos 《Fish and Fisheries》2020,21(1):162-189
Since the beginning of the 21st century, electronic monitoring (EM) has emerged as a cost‐efficient supplement to existing catch monitoring programmes in fisheries. An EM system consists of various activity sensors and cameras positioned on vessels to remotely record fishing activity and catches. The first objective of this review was to describe the state of play of EM in fisheries worldwide and to present the insights gained on this technology based on 100 EM trials and 12 fully implemented programmes. Despite its advantages, and its global use for monitoring, progresses in implementation in some important fishing regions are slow. Within this context, the second objective was to discuss more specifically the European experiences gained through 16 trials. Findings show that the three major benefits of EM were as follows: (a) cost‐efficiency, (b) the potential to provide more representative coverage of the fleet than any observer programme and (c) the enhanced registration of fishing activity and location. Electronic monitoring can incentivize better compliance and discard reduction, but the fishing managers and industry are often reluctant to its uptake. Improved understanding of the fisher's concerns, for example intrusion of privacy, liability and costs, and better exploration of EM benefits, for example increased traceability, sustainability claims and market access, may enhance implementation on a larger scale. In conclusion, EM as a monitoring tool embodies various solid strengths that are not diminished by its weaknesses. Electronic monitoring has the opportunity to be a powerful tool in the future monitoring of fisheries, particularly when integrated within existing monitoring programmes. 相似文献
680.
M. P. Newberry N. Phan‐Thien O. R. Larroque R. I. Tanner N. G. Larsen 《Cereal Chemistry》2002,79(6):874-879
The rheology of yeasted bread doughs is a little‐studied field despite yeast's importance in developing bread structure. A method of thermally inactivating the yeast within mixed bread doughs was developed to overcome the difficulty of yeast fermenting during rheological measurements. Sample stabilization by preshearing of dough samples at a stress amplitude of 1 Pa at 1 Hz for 10 sec improved the reliability of small amplitude oscillatory shear measurements, and resting 20 min within the rheometer was sufficient to produce reliable and consistent observations. Small amplitude oscillatory shear measurements were unable to detect any differences between yeasted and nonyeasted doughs nor any changes in linear viscoelastic properties due to fermentation. However, large strain uniaxial elongation measurements of yeasted doughs revealed a significant progressive decrease in elongational viscosities with fermentation. Size‐exclusion HPLC analysis of yeasted doughs showed an increase in unextractable polymeric dough proteins, which were interpreted as evidence of cross‐linking and therefore a potential improvement in dough properties. The apparent contradictions between uniaxial elongation and SE‐HPLC studies of fermenting yeasted doughs can be attributed to gas bubbles within the dough interrupting the increasingly cross‐linked protein network, resulting in the rheological weakness observed for fermenting yeasted doughs. 相似文献