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131.
de Medeiros Erika Valente Lima Neyla Thayná de Sousa Lima José Romualdo Pinto Kedma Maria Silva da Costa Diogo Paes Franco Junior Cícero Luiz Souza Rodolfo Marcondes Silva Hammecker Claude 《Phytoparasitica》2021,49(4):713-726
Phytoparasitica - The current agricultural scenario faces a range of challenges, with phytosanitary ones being paramount. In most cases, plant diseases are treated with chemicals; however, they... 相似文献
132.
Hela Chikh-Rouhou Rafael González-Torres Ali Oumouloud José M. Alvarez 《Euphytica》2011,182(2):177-186
The resistance to Fusarium oxysporum f.sp. melonis (Fom) race 1.2 has been studied in melons, such as the Portuguese accession ‘BG-5384’ and in the Japanese ‘Shiro Uri Okayama’,
‘Kogane Nashi Makuwa’, and ‘C-211’, since a good characterization of the resistance is necessary before its introgression
into commercial varieties. These four melon accessions showed a high level of resistance to races 0, 1, and 2 of Fom, indicating that the partial resistance to the race 1.2 previously detected may not have been race specific. To determine
the mode of inheritance of the resistance to Fom race 1.2, the F1, F2, BCPR, and BCPS generations from the crosses between the four resistant accessions above and ‘Piel de Sapo’, a Fom race 1.2 susceptible melon, were developed. They were subsequently inoculated with two Fom isolates, one from the pathotype 1.2Y and the other from the pathotype 1.2W. The area under the disease progress curve was
determined for each inoculated plant, and the data were analyzed. We show that the resistance seen in these accessions is
polygenically inherited with a complex genetic control because many epistatic interactions were detected. The three epistatic
effects; additivity × additivity, dominance × dominance, and dominance × additivity are present and significant, with differing
magnitudes from one cross to the next. The relatively low heritabilities, and these epistatic effects make difficult the improvement
of the resistance, from these sources, through a standard selection procedure. 相似文献
133.
Janaina O Luna Manoel A A Santos Edison L Durigon Jo?o P Araújo Júnior José M B Duarte 《Journal of zoo and wildlife medicine》2003,34(4):414-415
Esophageal-pharyngeal fluids from 53 free-ranging marsh deer (Blastocerus dichotomus) captured for a research program in the state of Mato Grosso do Sul, Brazil, were assayed for tuberculosis. Total DNA was extracted. amplified by polymerase chain reaction using specific primers for Mycobacterium tuberculosis complex (M. tuberculosis, M. bovis, M. microti, and M. africanum), and observed by agarose gel electrophoresis stained with ethidium bromide. All samples were negative. This, along with necropsy and histopathology data, suggests that these animals are not shedding and probably do not have active disease. 相似文献
134.
135.
self-(in)compatibility almond genotypes: A review 总被引:1,自引:0,他引:1
To compile self-(in)compatibility almond genotypes, a review of 133 commercial cultivars of wide geographical origin was made. The information gathered from own and mainly published work will be useful for both grower's cultivar choice when planting and for breeder's cross design when planning. The almond S genotypes compiled were identified using five different methods: biological (pollination tests in the field and in the laboratory) and molecular (RNases, PCR and sequencing). In most cases, genotypes were assigned after combining more than one technique. Cultivars were classified into three categories: self-incompatible (99), self-compatible (16) and doubtful self-incompatible (18). The database is divided in 9 fields (name, origin, parentage, obtention year (crossing, selection or release), S genotype, technique used, reference, consensus genotype, and cross incompatibility group). A study of the 27 S alleles already identified and their geographical distribution within the cultivated almond is also presented. The study was divided into cultivars of known and unknown parentage and the distribution of S alleles frequencies was uneven among the 133 cultivars. S allele frequencies are related to geographical origin. Some alleles (S
1, S
5, S
7 and S
8) are more frequently observed than the others among cultivars of both known and unknown parentage. In the cultivated almond, the S
f allele is only found in the Puglia region, Italy. The S
f
frequency is three times higher in cultivars released from breeding programmes than in cultivars selected by growers. From the 351 resulting possible genotypes by combination of the 27 S alleles identified only 20 CIG (0-XIX) have been established, which represents a small fraction of the whole genetic diversity of this polymorphic gene in almond. 相似文献
136.
A new sunflower mutant, CAS-12, was obtained, which has both high palmitic (≈30%) and high oleic acid contents, and also a
substantial amount of palmitoleic acid (≈7%). The mutant was selected after X-ray irradiation of dry seeds of the inbred line
BSD-2-423, which had normal palmitic (≈3%) and high oleic (≈88%) acid levels. The increase of palmitic and palmitoleic acids
occurred at the expense of the oleic acid content, which decreased to around 55% in respect to the original line. Linoleic
acid content is always under 5%. Palmitic and palmitoleic acid levels were similar to those of the high palmitic mutant CAS-5
obtained in a previous programme from a low oleic line isogenic to BSD-2-423 using a similar mutagenic treatment. In that
previous programme we also selected three high stearic acid mutants using chemical mutagenic treatment on the same sunflower
line (RDF-1-532). We attempted to obtain mutants in other lines but were unsuccessful. The isolation of similar mutants in
isogenic parental lines illustrates the importance of the genetic background in the development of specific mutants with an
altered seed oil fatty acid composition. The oil of this mutant will increase the range of potential uses of sunflower oil.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
137.
José F. Barbosa-Neto Carlos M. Hernández Louise S. O’Donoughue Mark E. Sorrells 《Euphytica》1997,98(1-2):59-67
Genetic progress through selection is directly related to the amount of variability present in the population and the quality
of genes contributed by the parents. Genetic relationships between lines were studied using DNA marker-based estimates of
genetic similarity. A statistical methodology using the width of a confidence interval was developed to determine the number
of probes to be surveyed and the precision in the estimation of genetic distance between pairs of cultivars. Precision was
affected by type of genetic distance used, the number of cultivars, and amount of genetic diversity present in the studied
group. The width of a (1-α)% confidence interval decreased as the number of RFLP fragments increased. Oat and wheat diversity
studies were used to illustrate the methodology.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
138.
Genetic relationships among 18 accessions, including 16 of Ananas and two of Pseudananas, were investigated using RAPD molecular markers. The procedure for DNA extraction was adapted from the method of Dellaporta
et al. (1983) where an incubation in proteinase K and a purification step were included. From the total of 148 markers scored,132
(89.2%) were polymorphic. The similarity matrix was used for cluster analysis. The phenogram developed from the RAPD bands
showed that for most of the cases, the accessions within a species grouped together. Nevertheless, a moderate infraspecific
genetic variation was observed. For example, DNA data grouped all A. comosus accessions with a mean similarity coefficient of 0.85. Comparable results were obtained with all other species investigated.
The highest genetic divergence was found withinA. lucidus where the mean similarity coefficient among accessions was0.75. A similar level of genetic polymorphism was observed among
species,therefore, a definition about which species were involved in the constitution of A. comosus genotypes was not possible. These results agree with the breeders standpoint suggesting that all Ananas species belong to the primary gene pool of pineapple.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
139.
André M. Almeida Anabela B. Silva Susana S. Araújo Luís A. Cardoso Dulce M. Santos José M. Torné Jorge M. Silva Matthew J. Paul Pedro S. Fevereiro 《Euphytica》2007,154(1-2):113-126
We have previously obtained several lines of tobacco transformed with a trehalose-6-phosphate synthase gene of plant origin
(Arabidopsis thaliana), involved in the first step of the biosynthesis of trehalose, a known osmoprotectant. Two showed distinct intensity of expression:
high (B5H) and low (B1F). Such lines were analyzed for trehalose-6-phosphate content and the obtained results demonstrated
to be in accordance with the expression results. In order to study the responses of photosynthesis to water deficit of transgenic
lines in comparison to wild type (WT), three experiments were performed under different conditions: (1) Relative water (2)
Leaf gas exchange (3) Modulated Chlorophyll a Fluorescence. Different responses in RWC of plant lines to water withdrawal were detected, with transgenic line B5H indicating
less water loss after the water withdrawal period. Similar responses to water deficit regarding the leaf gas exchanges were
recorded for the three lines. When subjected to water deficit stress situations, higher F
v/F
m, ΦPSII and qP were detected for the transgenic lines. Under a SWC of 20% where higher values for such parameters were detected with
special relevance for the B5H line, indicating a possible higher ability to withstand severe drought stress and to resist
to prolonged periods without water than the B1F and WT lines. 相似文献