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271.
Baseline sensitivity of maize borers in India to the Bacillus thuringiensis insecticidal proteins Cry1A.105 and Cry2Ab2 下载免费PDF全文
272.
N. V. Nair A. Selvi T. V. Sreenivasan K. N. Pushpalatha Sheji Mary 《Genetic Resources and Crop Evolution》2006,53(1):163-169
The potential use of RAPD markers in identifying genuine intergeneric hybrids of Saccharum was examined in 12 hybrids of Saccharum with Erianthus spp., Sorghum bicolor and Zea mays. In the three groups of hybrids examined, RAPD markers could precisely identify the true hybrids of Saccharum officinarum × Sorghum bicolor and Saccharum officinarum × Zea mays. Though Erianthus had a very distinct RAPD profile and as many as 107 Erianthus-specific bands were identified, a decisive profile that can identify all the hybrids could not be obtained. The strong molecular
differentiation between S.officinarum and Erianthus was not adequately resolved in the RAPD profiles of their hybrid progenies which suggest that more refined molecular techniques
will be required for the characterization of Saccharum–Erianthus hybrids. 相似文献
273.
Contribution of trees to soil carbon sequestration under agroforestry systems in the West African Sahel 总被引:1,自引:0,他引:1
Consequent to recent recognition of agricultural soils as carbon (C) sinks, agroforestry practices in the West African Sahel
(WAS) region have received attention for their C sequestration potential. This study was undertaken in the Ségou region of
Mali that represents the WAS, to examine the extent of C sequestration, especially in soils, in agroforestry systems. Five
land-use systems were selected in farmers’ fields [two traditional parkland systems, two improved agroforestry systems (live
fence and fodder bank), and a so-called abandoned land]. Soil samples taken from three depths (0–10 cm, 10–40 cm, and 40–100 cm)
were fractionated into three size classes (2,000–250 μm, 250–53 μm, and <53 μm) and their C contents determined. Whole-soil
C contents, g kg−1 soil, across three depths ranged from 1.33–4.69 in the parklands, 1.11–4.42 in live fence, 1.87–2.30 in fodder bank, and
3.69–5.30 in abandoned land; and they correlated positively with silt + clay content. Using the 13C isotopic ratio as an indicator of relative contribution of trees (C3 plants) and crops (C4 plants) to soil C, more tree-origin
C was found in larger particle size and surface soil and indicated that long-term tree presence promoted storage of protected
C in deeper soil. Existing long-standing agroforestry practices of the region such as the parklands seemed to have little
advantage for sequestering additional C, whereas improved agroforestry practices such as live fence and fodder bank introduced
in treeless croplands seemed to be advantageous. 相似文献
274.
Sujata Misra Awadhesh Kumar Srivastava Sushma Verma Sudhakar Pandey Surendra Singh Bargali Tikam Singh Rana K. Narayanan Nair 《Genetic Resources and Crop Evolution》2017,64(5):995-1010
Genetic variations and relationships among cultivated and wild genotypes of five taxa of Indian Luffa were examined using inter simple sequence repeats (ISSR), directed amplification of minisatellite DNA (DAMD) markers and morphological characterization. Morphometric evaluation of 21 discrete characters in 51 representative accessions segregated the five taxa of Luffa in three main clusters: the two wild species (L. echinata, L. graveolens) in the first, and the cultivated L. aegyptiaca (smooth gourd) and L. acutangula (ridged gourd)/L. hermaphrodita (Hermaphrodite luffa) in the second and third clusters, respectively. Cumulative data analysis of 15 ISSR and seven DAMD markers revealed high percentage polymorphism (97.67 %), moderate genetic distance (0.06–0.72, avg. 0.51), and low heterozygosity and Shannon index values (H = 0.15; I = 0.22) across all the 76 genotypes assayed. A UPGMA dendrogram, based on the combined marker data, resolved the five taxa in two main clusters with high bootstrap support. The morphological and molecular trees showed incongruence in the number of main clusters resolved and in the disposition of the wild and cultivated taxa in different sub-clusters. The cluster analyses and PCoA plots revealed a nested grouping of the hermaphrodite luffa within the ridge gourd group. The Bayesian STRUCTURE analysis identified three genetic clusters for the five assumed taxa. Outcrossing test revealed a mixed mating system in Indian Luffa. This is the first ever report on the mating system in Luffa using molecular markers. The study also demonstrates the utility of using more than one DNA marker in the assessment of molecular diversity in a widely cultivated crop genus like Luffa with a narrow genetic base. 相似文献
275.
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278.
The domestic cat is an excellent model for the development of therapeutic protocols that target hematopoietic stem cells (HSCs) because it is relatively resistant to complications related to bone marrow transplantation. To identify a plentiful source of HSC that could be used as targets for gene transduction and transplantation, the livers of 28 mid-gestation fetuses (28-52 days) and late-gestation fetuses (53 days-term) were analyzed for erythroid, myeloid, lymphoid, and uncommitted hematopoietic progenitor cells by flow cytometry. We found that the fetal liver mononuclear cells (FLMCs) contained 57% erythroid progenitors during mid-gestation, but this percentage declined to 43% as gestation progressed. Myelomonocytic cells within FLMC were more numerous in late-gestation (31%) than in mid-gestation (18%). Two monoclonal antibodies (mAb), CH 152 and CH 755, which recognize cells with the potential to reconstitute multilineage hematopoiesis in cats, were tested. Approximately, 32% of FLMC from late-gestation fetuses expressed the epitope recognized by mAb CH 152, a significant increase above the 12% positive cells in mid-gestation fetuses. Approximately, 33% of hepatic mononuclear cells expressed the epitope recognized by mAb CH 755 in both mid-term and late-term fetuses. When expressed in absolute numbers, medians of 2.7 x 10(7) CH 152-positive cells and 3.2 x 10(7) CH 755-positive cells were extracted from the late-term fetal livers of individual cats. T-lymphocytes were a minor component (<3%) of FLMC, despite their presence in the thymus and spleen. These data suggest that the late-term feline fetal liver is a suitable source of mutipotential hematopoietic cells that could be used for gene therapy protocols in the cat. 相似文献
279.
Phenotypic and genotypic characterization of bovine mastitis isolates of Staphylococcus aureus for biofilm formation 总被引:1,自引:0,他引:1
Staphylococcus aureus is one of the most common pathogens responsible for contagious mastitis in ruminants. The ability of S. aureus to form biofilm in vivo is considered to be a major virulence factor influencing its pathogenesis in mastitis. The objectives of the study were to examine in vitro slime production, biofilm formation, and the presence of the ica gene locus and icaA and icaD genes in S. aureus isolates from bovine mastitis. Thirty-two of the 35 isolates tested produced slime on Congo red agar, whereas only 24 of the isolates were found to produce biofilm in vitro. However, all the 35 isolates possessed the ica locus, icaA and icaD genes. This study indicates a high prevalence of the ica genes among S. aureus mastitis isolates, and their presence is not always associated with in vitro formation of slime or biofilm. A combination of phenotypic and genotypic tests is recommended for investigating biofilm formation in S. aureus. 相似文献
280.