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641.
A unique morphological cell type, "microfold or membranous (M) cell-like cell", was detected electron-microscopically in the cecal tonsil epithelium of the chicken. M cell-like cells possessed a few short microvilli of irregular arrangement and a large number of lymphocytes and macrophages wedged into their basal surfaces. Triticum vulgaris was found to bind to M cell-like cells. With horseradish peroxidase (HRP) treatment, M cell-like cells showed an active HRP uptake just as did the neighbouring usual absorptive epithelial cells. No uptake of colloidal carbon particles from the intestinal lumen was recognized in any part of the intestinal epithelium. These results suggest that M cell-like cells of the chicken possess some M cell-characteristic morphological and histochemical features, but that their active uptake of foreign materials is not so developed as in mammalian M cells.  相似文献   
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644.

Background  

The isolation of green fluorescent protein (GFP) and the development of spectral variants over the past decade have begun to reveal the dynamic nature of protein trafficking and organelle motility. In planta analyses of this dynamic process have typically been limited to only two organelles or proteins at a time in only a few cell types.  相似文献   
645.
The induction of flowering under long‐day conditions is an important adaptation by short‐day plants, such as adzuki beans (Vigna angularis), to high‐latitude environments. This study clarified the genetic control underlying the long‐day insensitivity of adzuki bean cultivar ‘Shumari’. ‘Shumari’ was found to be insensitive to a 16‐h day, whereas landrace Acc2265 was highly sensitive. When grown under natural long‐day conditions at Obihiro (42°9′N), Acc2265 initiated flowering at least 80 days after ‘Shumari’. When 86 recombinant inbred lines (RILs) derived from crosses between ‘Shumari’ and Acc2265 were grown under these conditions, their flowering dates ranged from the middle of July to the end of October. The distinct bimodal distribution in the RIL population was due to a single major gene, designated Flowering Date1 (FD1). Molecular mapping showed that FD1 was located between the SSR markers Az02‐37M3 and Az02‐40M9, at distances of 6 and 10.4 cM, respectively, on linkage group 2. RILs carrying FD1S lacked long‐day sensitivity, whereas RILs carrying FD1A were sensitive to long‐day conditions, confirming that FD1 controls long‐day sensitivity.  相似文献   
646.
A triploid hybrid, which was obtained from interspecific crosses between tetraploid Primula denticulata (2n = 4x = 44) and P. rosea (2n = 2x = 22), successfully produced 11 plants by backcrossing with pollen of tetraploid P. denticulata. Analysis of ploidy level using flow cytometry and chromosome counting in the 11 BC1 plants revealed that all progeny had much larger DNA contents and chromosome number than both parents. In this triploid-tetraploid (3x–4x) crossing, progeny was predominantly true or near pentaploid presumably produced by the fertilization between true or near triploid female gamete produced from triploid hybrid and diploid pollen of tetraploid P. denticulata. These results suggest that unreduced (3x) or near triploid female gametes were partially produced by single step meiosis, either first-division restitution or second-division restitution process. The zygotes formed by the fertilization between true or near triploid egg produced by single step meiosis in triploid hybrid and diploid pollen produced by normal meiosis of tetraploid P. denticulata might be the only survivors in embryogenesis.  相似文献   
647.
An improved enzyme-linked immunosorbent assay (ELISA) for detection of heterophile Hanganutziu-Deicher (HD) antibodies and antigens, which are frequently detected in sera and/or cancerous tissues from patients with various cancers was developed using biotinylated chicken anti-GM3(NeuGc) antibody and avidin-horseradish peroxidase conjugate. The N-glycolylneuraminyllactosyl-ceramide, GM3(NeuGc) ganglioside was purified from horse erythrocyte membranes. The ELISA procedure required 300 ng GM3(NeuGc) antigen to coat plastic microtiter plates and 190 ng biotinylated antibody per well to give optimum product formation. The technique could detect 6 ng antigen in tissue homogenate as compared to 0.6 ng of the pure compound by inhibition. Chicken anti-GM3(NeuGc) antibody quantitatively inhibited the biotinylated antibody, however, this procedure was not suitable to quantify lower affinity HD antibody in patient sera. Immunostaining specific for HD antigen-positive cells, in tissue sections was by 4 micrograms/ml biotinylated antibody and 200 dilution of Avidin-biotinylated peroxidase complex reagent using pig intestine and lymph node as positive tissues and chicken intestine and lung as negative tissues.  相似文献   
648.
Osteochondrosis developed from the early growing process of articular cartilage at the caudal-central region of the medial femoral condyle in rats. Articular cartilage was thick at the region. Mineralization of the matrix in the thick deep zone was incomplete and major parts remained unmineralized. Cavity formation in the mineralized matrix resulting in osteochondrotic lesions was present in the deep zone at 6 weeks of age and was followed by an appearance of viable chondrocytes around it. Osteochondrotic lesions were present from the age of 10 weeks for females and 12 weeks for males. Cavities were expanded and increased in number, and eosinophilic necrotic foci were additionally seen. These changes were extended throughout the deep zone, and viable chondrocytes were also increased in number. The thick deep zone was retained and had no detectable invasions of blood vessels from the subchondral bone. At 20 weeks of age, necrotic areas containing large clefts were present in the basal layer of the thick deep zone and fibrotic lesions were seen beneath them. In normal cases, invasions of blood vessels were seen in the basal layer of the deep zone and also in the cavities of the cartilage; the deep zone was markedly thinned at 20 weeks of age.  相似文献   
649.
Apyrases (NTPases) are associated with both compatible and incompatible interactions between plants and microorganisms. Previously we reported that the ATPase activities of cell-wall-bound apyrases of several leguminous plants, such as pea, cowpea, soybean, and kidney bean, were enhanced by a glycoprotein elicitor and were inhibited in a species-specific manner by mucin-type glycopeptide suppressors secreted from a pea pathogenic fungus, Mycosphaerella pinodes. In this study, we isolated two apyrase genes, VsNTPase1 and VsNTPase2, from a cDNA library of Vigna sinensis Endl. cv. Sanjakusasage. Based on phylogenetic analysis, VsNTPase1 may belong to a group that responds to environmental stimuli. In a transient assay using DNA bombardment, a fusion protein of green fluorescent protein (GFP) and the N-terminal putative signal sequence of VsNTPase1 was distributed in the nucleus, cytoplasm (cytoskeletal structure), and cell wall. On the other hand, a fusion protein of GFP and the N-terminal putative VsNTPase2-signal sequence was localized in the cytoplasm, especially in small particles (perhaps mitochondria). A recombinant VsNTPase1 expressed in Spodoptera frugiperda 21 cells responded directly to signal molecules from several phytopathogenic microorganisms. Here, we discuss the role of apyrases in recognizing and responding to exogenous signals. The nucleotide sequences of VsNTPase1 and VsNTPase2 in this article have been submitted to DDBJ as accession numbers AB196769 and AB196770, respectively.  相似文献   
650.
The sequences of a small RNA segment of Aino virus isolates were analyzed to define the molecular epidemiology and genetic relationships to other species in the genus Orthobunyavirus in the family Bunyaviridae. The nucleotide and amino acid sequences of the segment were highly conserved among strains isolated from 1964 to 2002 in Japan. These Japanese isolates were segregated into two distinct lineages, one containing the prototype strain JaNAr28 isolated in 1964 and the other containing strains isolated after 1986, by phylogenetic analysis based on the nucleocapsid gene sequences. Japanese strains isolated after 1986 were rather more closely related to Kaikalur virus isolated in India in 1971 than to strain JaNAr28. On the other hand, an Australian strain, B7974, was closely related to Peaton virus. The B7974 strain might have been generated by inter-serotype genetic reassortment between Aino and Peaton viruses in Australia during their evolution. However, recent Aino virus strains isolated in Japan appear to be genetically stable.  相似文献   
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