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821.
Genes involved in late specification of the mandibular arch, the source of the vertebrate jaw, are expressed with similar patterns in the oral regions of chick and lamprey embryos. However, morphological comparisons indicate that apparently orthologous homeobox genes were expressed in different subdivisions of the ectomesenchyme in the two species. Therefore, the homology and gene expression of the oral region are uncoupled during the transition from agnathan to gnathostome; we conclude that a heterotopic shift of tissue interaction was involved in the evolution of the jaw.  相似文献   
822.
Dwarf plants were obtained in an F2 population of a cross betweenSolanum chacoense (clone chc 525-3) andS. phureja (clone 1.22). Segregation analyses in F2 and backcross populations suggested that the dwarfism was controlled by a single recessive gene transmitted fromS. phureja clone 1.22. The dwarf plants responded to treatment with gibberellic acid, which recovered normal growth. We named this gene‘ga 2’. Linkage analysis of the genega 2 with RFLP and RAPD markers indicated that the genega 2 was located on the most or near distal end of chromosome 7.  相似文献   
823.
The distribution of lectin bindings in the testis of the smallest ruminant, lesser mouse deer (Tragulus javanicus), was studied using 12 biotinylated lectins specific for d ‐galactose (peanut agglutinin PNA, Ricinus communis agglutinin RCA I), N‐acetyl‐d ‐galactosamine (Dolichos biflorus agglutinin DBA, Vicia villosa agglutinin VVA, Soybean agglutinin SBA), N‐acetyl‐d ‐glucosamine and sialic acid (wheat germ agglutinin WGA, s‐WGA), d ‐mannose and d ‐glucose (Lens culinaris agglutinin LCA, Pisum sativum agglutinin PSA, Concanavalin A Con A), l ‐fucose (Ulex europaeus agglutinin UEA I), and oligosaccharide (Phaseolus vulgaris agglutinin PHA‐E) sugar residues. In Golgi‐, cap‐, and acrosome‐phase spermatids, lectin‐bindings were found in the acrosome (PNA, RCA I, VVA, SBA, WGA and s‐WGA), and in the cytoplasm (PNA, RCA I, VVA, SBA, WGA, LCA, PSA, Con A and PHA‐E). s‐WGA binding was confined to the spermatid acrosome, but other lectins were also observed in spermatocytes. In spermatogonia, VVA, WGA, Con A, and PHA‐E bindings were observed. Sertoli cells were intensely stained with DBA and Con A, and weakly with PHA‐E. In interstitial Leydig cells, RCA I, DBA, VVA, Con A, PSA, LCA, WGA and PHA‐E were positive. UEA I was negative in all cell types including spermatogenic cells. Unusual distribution of lectin‐bindings noted in the testis of lesser mouse deer included the limited distribution of s‐WGA only in the spermatid acrosome, the distribution of DBA in Sertoli cells, Leydig cells and lamina propria, and the absence of UEA I in all type cells. The present results were discussed in comparison with those of other animals and their possible functional implications.  相似文献   
824.
The 3D internal structure microscopy (3D-ISM) was applied to the equine ovary, which possesses peculiar structural characteristics. Stereolithography was applied to make a life-sized model by means of data obtained from 3D-ISM. Images from serially sliced surfaces contributed to a successful 3D reconstruction of the equine ovary. Photopolymerized resin models of equine ovaries produced by stereolithography can clearly show the internal structure and spatial localizations in the ovary. The understanding of the spatial relationship between the ovulation fossa and follicles and/or corpora lutea in the equine ovary was a great benefit. The peculiar structure of the equine ovary could be thoroughly observed and understood through this model.  相似文献   
825.
The efficacy of cyazofamid was tested against pearl millet downy mildew disease caused by Sclerospora graminicola Schroet. Significant inhibition of sporangial sporulation, zoospore release and motility was observed at 0.3 mg mL(-1), and this concentration also provided good fungicidal activity under in vitro conditions. Under glasshouse conditions, none of the concentrations tested, either 0.01-2 mg mL(-1) as seed treatment or 1-10 mg mL(-1) by foliar application, was found to be phytotoxic. The effect of cyazofamid was tested by seed treatment alone, seed treatment followed by foliar application and foliar application alone. Seed treatment with cyazofamid offered only 19.7% disease control, but seed treatment followed by a single foliar application to diseased plants provided good control over disease, seed treatment with two foliar applications was significantly superior and foliar application alone showed a high level of activity, with 10 mg mL(-1) giving 97.9% disease control. Lack of systemic activity of cyazofamid was evident, root treatment giving disease levels on a par with the untreated control. The fungicide exhibited strong curative activity, but only moderate translaminar activity, with only marginal (34.8%) disease control after treatment of the adaxial leaf surface at 10 mg mL(-1). Loss of cyazofamid activity over time was very low, indicating stable residual and rainfastness activity. These results indicate that cyazofamid has a high potential to be an effective fungicide for the control of downy mildew disease of pearl millet.  相似文献   
826.
Protamine is a basic protein whose sulfate is used in medical applications as a carrier for injectable insulin and as a heparin antagonist, while its hydrochloride is used as an antibacterial ingredient for some food products. We previously showed that protamine hydrochloride derived from chum salmon milt inhibited pancreatic lipase and reduced plasma triacylglycerol levels in an oral fat tolerance test in humans. The present study evaluated the effect of chum protamine hydrochloride on lipid metabolism in rats. The single oral administration of protamine hydrochloride (500 mg/kg) reduced plasma triacylglycerol levels in a corn oil tolerance test, and repeated oral administration at a dose of 0, 150, 500, or 1,500 mg/kg with a high fat diet for 7 weeks significantly reduced body weight gain, liver weight, and epididymal adipose tissue, whereas total calorie intakes were not significantly different. These findings could be caused by the suppression of lipid digestibility leading to a significant increase in fecal lipid excretion due to the fact that protamine hydrochloride could bind with bile acids to make a complex that is difficult to digest. Protamine hydrochloride, with a considerable history as food, can be considered to be promising as an anti-obesity functional food material.  相似文献   
827.
ABSTRACT:   Aspolin is a polyaspartic acid-like protein, which is originally isolated from walleye pollack Theragra chalcogramma muscle as trimethylamine- N -oxide (TMAO) demethylase. Although carp Cyprinus carpio muscle contains a trace amount of the enzyme substrate, TMAO, aspolin can be extracted and purified by acid treatment, successive chromatographies and polyacrylamide gel electrophoresis, and has twice the amount of that in walleye pollack muscle. Carp aspolin showed a low enzymatic activity in the presence of Fe2+ and reductants, and its Km value (100 mM) to TMAO was extremely high. It was a thermostable protein and had an unfolded conformation. The amino acid sequence of carp aspolin 1 deduced from cDNA revealed that it contained a long Asp polymer, an uninterrupted stretch of 138 Asp residues, followed by four amino acid residues, His-Glu-Glu-Leu, in C-terminus. The chain length was shorter by 42 Asp residues than that of its walleye pollack counterpart.  相似文献   
828.
829.
An orthoreovirus was isolated from an Ostrich (Struthio camelus) and rapidly identified as orthoreovirus by the rapid determination of viral RNA sequences (RDV) system and electron microscopy. Phylogenetic analysis of the sigma A protein indicated that the isolate belonged to avian species and was closely related to chicken orthoreovirus strain 138. The results of the present study indicated that an ostrich orthoreovirus is slight different from other chicken orthoreoviruses and provided evidence of diversity among avian orthoreoviruses. To our knowledge, this is the first genetic report of an orthoreovirus isolated from an ostrich.  相似文献   
830.
The present study investigated severe fever with thrombocytopenia syndrome virus (SFTSV) infection in raccoons in Wakayama Prefecture from 2007 to 2019. To perform surveillance, an enzyme-linked immunosorbent assay (ELISA) was established, and the sensitivity and specificity of the ELISA were 100% in comparison with a 50% focus-reduction neutralization assay. Using the established ELISA, we performed serosurveillance of SFTSV infection in 2,299 raccoons in Tanabe region, Wakayama Prefecture from 2007 to 2019. The first anti-SFTSV-positive raccoon was captured in October 2009. The seroprevalence of SFTSV infection was <10% between April 2009 and March 2013, 23.9% between April 2013 and March 2014, 37.5% between April, 2014 and March 2015, and over 50% from April 2015. Next, we performed detection of SFTSV genes in sera of raccoons captured in Wakayama Prefecture after April 2013. The results indicated that 2.4% of raccoons were positive for SFTSV genes and that the frequency of SFTSV infection among raccoons between January and March (0.7%) was lower than that between April and June (3.4%). In addition, virus genes were detected from many specimens, including sera and feces of two raccoons, and viral antigens were detected in lymphoid cells in lymphoid follicles in the colon by immunohistochemical staining. In conclusion, SFTSV had recently invaded the area and had rapidly spread among wild animals. The first patient in this area was reported in June 2014, indicating that raccoons are good sentinels for assessing the risk of SFTSV in humans.  相似文献   
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