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81.
Ahmed Ibrahem I. Badawy Kathleen Lutz Anja Taubert Horst Zahner Carlos Hermosilla 《Veterinary research communications》2010,34(2):103-118
Host immune responses conducted against antigens of Eimeria bovis are key factors for the development of protective immunity against this protozoan disease. In this study we investigated
the expression of E. bovis-derived antigens on the host cell surface membrane during E. bovis first merogony in vitro. Host cells carrying E. bovis-meront I stages expressed E. bovis host cell surface antigens (EbHCSAg) on their surface membrane which were recognised by hyperimmune sera of calves and by
sera from rats immunized with E. bovis merozoites I, when tested by indirect immune fluorescent antibody test (IIFAT), laser scanning confocal microscopy (LSCM)
and immune electron microscopy. Expression of EbHCSAg on permissive host cells was earliest detected 7 days p. i., thus coinciding
with the onset of the parasite replication. Membrane-associated EbHCSAg were removed from infected host cells by proteinase
K, partially by Triton X-100, Triton X-114 and Triton X-405, but not by 1 M NaCl, CHAPS or phospholipase C treatment. Antibodies,
affinity-purified on paraformaldehyde/glutardialdehyde (PAGA)-fixed E. bovis meront I-infected bovine host cells bound to the surface meront I-carrying cells and to merozoites I (IIFAT, LSCM) but, in
contrast to untreated sera, not to sporozoites. When tested on methanol-fixed merozoites I and sporozoites by IIFAT, affinity-purified
antibodies bound to structures in the apical complex area of merozoites I, but not to sporozoites, whilst untreated sera caused
diffuse labelling of internal structures of both parasite stages. Immune electron microscopy demonstrated binding of affinity-purified
antibodies to micronemes and dense granules of merozoites I. Although the function of EbHCSAg is still unknown, results of
this study might suggest an involvement in the development of protective immunity against E. bovis infections. 相似文献
82.
Ahmed A. M. Awad Atef A. A. Sweed 《Communications in Soil Science and Plant Analysis》2020,51(8):1101-1113
ABSTRACT The objective of this study was to study the influence of three organic manures, farm yard manure (FYM), poultry manure (PLM), and pigeon manure (PGM), on soil physical and chemical properties on tuber yield of Jerusalem artichoke in a newly reclaimed saline calcareous soil. A field experiment was conducted applying the three manures, alone and/or in different combinations. Soils were investigated at surface (0–30 cm) and subsurface (30–60 cm) layers before and after planting, and analyzed for physical and chemical properties. The results indicated that the application of 31.5 kg ha?1 of PLM+10.5 kg of PGM T7 recorded highest available nitrogen, zinc, copper, and moisture content at the surface layer. The same results were obtained for iron and manganese at both layers. While, applying 21.0 kg ha?1 FYM+21.0 kg ha?1 PLM T10 recorded the best treatment for pH, phosphorus, zinc, copper, moisture content, and saturation percentage at the subsurface layer. Applying 21.0 kg ha?1 PGM + 10.5 kg ha?1 FYM+10.5 kg ha?1 PLM T15 recorded the best treatment for organic matter content and bulk density at surface layer and reduced the electrical conductivity and inulin tuber content at both layers. On the other hand, calcium carbonate and sodium adsorption ratio were reduced in both layers by applying 21.0 kg ha?1 PLM+10.5 kg ha?1 FYM+10.5 kg ha?1 PGM T14. The best treatment for tuber nitrogen content and total yield was obtained with applying 42.0 kg ha?1 PLM T2 only and 31.5 kg ha?1 FYM+10.5 kg ha?1 PLM T4, respectively. 相似文献
83.
Hamid ME Alla KM Ahmed SS El Shiekh AE Ibrahim KE 《Journal of the South African Veterinary Association》2006,77(2):90-91
We describe a rare case of a concurrent demodectic and sarcoptic mange in a 2-year-old heifer in Khartoum, Sudan. The lesions were massive lumps of granulomatous tumour-like dermatitis with thick, nodular folds mainly covering the head, neck and shoulders. Histopathological examination of the lesions revealed the presence of both Demodex bovis and Sarcoptes scabiei. The animal died regardless of the anti-parasitic treatment it received. 相似文献
84.
85.
The cytological status of plantlets regenerated from shoot apical meristems of Pisum sativum was investigated. Chromosome counts in root apices of in vitro regenerated plants showed a preponderance of diploid cells. Moreover, the karyotypes of root-tips from plants derived from culture and from normal plants were basically the same. Topics such as the treatment of chromosomal armlength data, simple statistical comparison of samples derived from normal and regenerated plants are discussed. 相似文献
86.
Summary Common blight disease in beans (Phaseolus vulgaris), caused by the bacterium Xanthomonas campestris pv. phaseoli, reduces crop yield and seed quality. Information is needed on the variation of leaves and pods disease reaction to strains of the bacterium after different inoculation methods. Phaseolus vulgaris cultivars Red Kidney Charlevoix, GN Harris, GN 1140, and GN Emerson were inoculated with three different strains of Xanthomonas campestris pv. phaseoli at two inoculum concentrations (108 and 106 bacterial cells/ml) using water soaking, multiple needle, and razor blade inoculation on leaves, and razor blade scratch, dissecting needle, and razor blade cut inoculation on pods. Differential cultivar disease reactions of leaves, pods, or both to the bacterial strains were observed in some cases. Significant interactions among cultivars, inoculation methods, strains, and inoculum concentrations (leaves) were found. A rapid leaf chlorosis developed 6 to 7 days after inoculation. Strains of bacteria did not show specificity in inducing this reaction, but rapid leaf chlorosis was associated with high inoculum concentration and with the water soaking and multiple needle methods. Another experiment was conducted to count the number of living bacterial cells deposited in the leaf tissue after inoculation by different methods. The number of bacteria deposited by water soaking or multiple needle was higher than that deposited by razor blade.Published as Paper No. 8584, Journal Series, Nebraska Agricultural Experiment Station. Research was conducted under Project No. 20–36. 相似文献
87.
Summary Studies on genetic diversity in chickpea (Cicer arietinum L.) indicated the existence of considerable amount of variation for grain yield and its components in the material. One hundred and thirty two genotypes fell into eight clusters. The covariation structure studied by means of factor analysis indicated the possibility of obtaining, through hybridization, genotypes physiologically and morphologically more efficient. Multivariate analysis of data from 7 parents and 21 F1 hybrids indicated weak correspondence between D2-analysis and canonical variate analysis. As there was no relationship between heterosis over midparent and genetic distance between the parents, so the traditional approach of making a large number of crosses is being suggested. 相似文献
88.
89.
Ahmed H. Khairy 《植物养料与土壤学杂志》1990,153(3):133-140
Increasing amounts from 2.5 to 45 μg of one synthetic and seven natural humic acids were chromatographed on silica gel thin layers using ammonia 25% and propanol in the ratio 70:30 v/v as mobile phase. The fragments of humic acids produced under the influence of the alkaline mobile phase were separated in three band-shaped chromatographic fractions, whose lengths were transverse to the direction of the mobile phase. Since the fragments were not formed in constant ratios from different quantities of the same humic acid, the length of a fraction could only reflect its content of humic substance, whereas the sum of lengths of the three fractions (F) reflected quantities of the humic acid (x) at starting points. Similar F-x curves were obtained from humic acids extracted from similar origins, even when the locations of the samples, particle weights of the humic acids or the pH values at which they were extracted were different. The mathematical relation between F and x for quantities of humic acids up to 15–20 μg possessed high correlation coefficients and may be thus applied for the estimation of unknown concentrations of humic acids extracted from similar origins. 相似文献
90.
K. M. Iftekharuddaula M. A. Newaz M. A. Salam H. U. Ahmed M. A. A. Mahbub E. M. Septiningsih B. C. Y. Collard D. L. Sanchez A. M. Pamplona D. J. Mackill 《Euphytica》2011,178(1):83-97
Flooding is one of the major hazards of rice production for the rainfed lowland rice ecosystem, and tolerant cultivars are
urgently needed to help protect farmers from submergence damage. A quick and efficient strategy was implemented to introgress
SUB1, a major QTL for submergence tolerance, into a rainfed lowland mega variety BR11 of Bangladesh by only two backcrosses and
one selfing generation. In marker-assisted backcrossing (MABC), one tightly-linked simple sequence repeat (SSR) and two gene-based
markers, four flanking SSR and 116 background SSR markers were used for foreground, recombinant and background selection,
respectively, in backcrosses between a SUB1 donor IR40931-33-1-3-2 and BR11. BR11-Sub1, identified in a BC2F2 plant, possessed BR11 type SSR alleles on all fragments analyzed except the SUB1 QTL. The introgression size in BR11-Sub1 was 800 Kb indicating approximately 99.8% identity to BR11. BR11-Sub1 along with
other introgression lines showed submergence tolerance similar to the tolerant parent. Yield, yield-component parameters and
grain physico-chemical properties showed successful recovery of the BR11 traits in BR11-Sub1, with yield potential ranging
from 5.2 to 5.6 t/ha, not significantly different from the recurrent parent mega variety BR11. Producing a large number (~1000)
of backcross F1 plants was considered essential to achieve recombination on both sides of the gene, limiting linkage drag with only two backcrosses.
A large number of background markers ensured proper recovery of the recurrent parent genome in the BC2F2 generation. The study demonstrates a rapid and highly precise strategy to introgress a major QTL by BC2F2 generation into a modern rice variety using an unadapted donor. The variety can replace BR11 on more than 2 million of ha
in Bangladesh and provide major increases in rice production. 相似文献