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991.
Hardenburg E. V. Tussing Earl B. Lauer K. W. Bailey H. L. 《American Journal of Potato Research》1941,18(9):270-271
American Journal of Potato Research - 相似文献
992.
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996.
V. 《Journal of pest science》1939,15(10):117-118
Ohne Zusammenfassung 相似文献
997.
T. T. Chen L. B. Agellon C. M. Lin H. J. Tsai Peijun Zhang L. I. González-Villasénor D. A. Powers 《Fish physiology and biochemistry》1989,7(1-6):381-385
The primary structures of two rainbow trout growth hormone mRNAs (GH1 and GH2) have been deduced by direct sequencing of their
respective cDNA clones and portions of the mRNA. Both GH1 and GH2 mRNA contain open reading frames comprised of 630 nucleotides
and encode 210 amino acid residues of which 11 are variant. The translated regions of both mRNA are flanked by a short but
rather conserved 5′-end, and a relatively long but highly diverged 3′-end. The differences at translated and 3′-untranslated
regions suggest that the GH1 and GH2 mRNA originate from different loci. The GH1 and GH2 mRNA are likely transcribed from
two distinct loci which were duplicated during tetraploidization of salmonid genome between 50 to 100 million years ago.
The GH2 gene has been isolated and sequenced from a rainbow trout genomic library. This gene spans a region of approximately
4 kilobases. The trout GH gene is comprised of 6 exons and 5 introns, in contrast to 5 exons and 4 introns in mammals. The
additional intron in the trout gene interrupts the translated regions that are analogous to the last exon of the mammalian
counterpart. The alleged internally repeating sequences in mammalian GH, prolactin (Pr1) and placental lactogen (PL) are not
observed in the predicted polypeptide sequence of trout GH. In addition, direct repeats that flank exons I, III and V of mammalian
GH, Pr1 and PL genes are absent in trout gene. These findings indicate that the rainbow trout GH gene structure does not support
the current hypothesis that internally repeated regions in GH, Pr1 and PL arose from a small primordial gene. 相似文献
998.
Castillo D Higuera G Villa M Middelboe M Dalsgaard I Madsen L Espejo RT 《Journal of fish diseases》2012,35(3):193-201
Flavobacterium psychrophilum causes rainbow trout fry syndrome (RTFS) and cold water disease (CWD) in salmonid aquaculture. We report characterization of F. psychrophilum strains and their bacteriophages isolated in Chilean salmonid aquaculture. Results suggest that under laboratory conditions phages can decrease mortality of salmonids from infection by their F. psychrophilum host strain. Twelve F. psychrophilum isolates were characterized, with DNA restriction patterns showing low diversity between strains despite their being obtained from different salmonid production sites and from different tissues. We isolated 15 bacteriophages able to infect some of the F. psychrophilum isolates and characterized six of them in detail. DNA genome sizes were close to 50 Kbp and corresponded to the Siphoviridae and Podoviridae families. One isolate, 6H, probably contains lipids as an essential virion component, based on its chloroform sensitivity and low buoyant density in CsCl. Each phage isolate rarely infected F. psychrophilum strains other than the strain used for its enrichment and isolation. Some bacteriophages could decrease mortality from intraperitoneal injection of its host strain when added together with the bacteria in a ratio of 10 plaque-forming units per colony-forming unit. While we recognize the artificial laboratory conditions used for these protection assays, this work is the first to demonstrate that phages might be able protect salmonids from RTFS or CWD. 相似文献
999.
Juan Antonio Ramirez‐Merlano Víctor Mauricio Medina‐Robles Pablo Emilio Cruz‐Casallas 《Aquaculture Research》2011,42(6):738-745
The effects of straws volume, cryoprotectants and thawing temperatures were evaluated on the sperm quality of cachama blanca Piaractus brachypomus (Cuvier), an important Colombian fish species. Sexually mature fish were induced to ovulation or spermiation with a carp pituitary extract. A pool of suitable sperm samples was diluted in glucose, egg yolk, dimethyl sulphoxide (DMSO‐10%), methanol (MET‐10%) or ethylene glycol (ETG‐5%) and packed in 0.5, 2.5 or 5.0 mL straws and frozen in nitrogen vapour. The thawing process was performed in a 35 or an 80 °C water bath. The fertility was evaluated after 6 h post fertilization. The highest motility percentage (33 ± 3%) was observed with sperm cryopreserved with DMSO, packed in 5 mL straws and thawed at 35 °C. The treatments with DMSO and MET packed in 0.5 and 5.0 mL straws and thawed at 35 °C showed the highest fertility (higher than 71%) and the lowest fertility was obtained with MET‐2.5 mL (9 ± 5%). In all the treatments, a significant decrease in the sperm quality was observed at 80 °C. Sperm cryopreserved with DMSO‐10% or MET‐10%, packed in 2.5 or 5.0 mL straws are suitable to achieve acceptable fertilization and to fertilize high amounts of eggs. 相似文献
1000.
The growth data of a commercial aquaculture recirculation system were analysed to investigate the growth performance of reared
turbot (Psetta maxima). Three common growth models (von Bertalanffy, Gompertz and Schnute) were fitted to the growth data documented over a time
period of 6 years. To determine the most suitable model, three different criteria were used: (1) the Akaike index criterion,
(2) the sum of squared residuals and (3) the average daily deviation between the estimated final weight and the observed final
weight. The evaluation of the growth models showed that the Schnute model had the lowest Akaike index, the lowest sum of squared
residuals and the lowest daily deviation between estimated and real weight of all tested growth models. The Schnute model
produced sigmoid growth curves. The estimated growth coefficients were the most realistic ones in regard to biological interpretation.
In contrast, the von Bertalanffy growth model and the Gompertz model estimated inaccurate exponential growth curves and are
therefore unable to simulate the growth data as well as the Schnute model. The results indicate that the von Bertalanffy growth
model is not the optimal model to simulate the present growth data and that the growth potential of reared turbot has probably
not yet been fully exploited in the aquaculture system(s) examined (so far). 相似文献