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11.
OBJECTIVE: To develop polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis for molecular typing of strains of Streptococcus zooepidemicus and to use the new typing method to analyze a collection of isolates from the respiratory tract of Thoroughbreds. SAMPLE POPULATION: 10 strains of S zooepidemicus, 65 isolates from the respiratory tract of 9 yearlings following long distance transportation, and 89 isolates from tracheal aspirates of 20 foals with pneumonia. PROCEDURE: Phenotypic variations in the SzP protein were detected by western immunoblot analysis. Using PCR-RFLP analysis, genotypes were obtained with primer sets from the SzP gene, followed by restriction endonuclease digestion of the amplicons. RESULTS: Unique genotypic patterns were obtained with a primer set designed from both ends of the structural gene and the restriction endonuclease DdeI. Forty-five isolates from the lymphoid tissue within the pharyngeal recess (ie, pharyngeal tonsil) of yearlings included 10 SzP genotypes and SzP phenotypes. Isolates from the trachea of each yearling were of a single genotype that was also present among isolates from the pharyngeal tonsil of the same horses. Isolates from tracheal aspirates of foals belonged to 14 genotypes. CONCLUSIONS AND CLINICAL RELEVANCE: Analysis of the SzP gene by use of PCR-RFLP was effective for molecular typing of strains of S zooepidemicus in the study of respiratory tract disease in horses. Results of PCR-RFLP analysis indicate that a single strain of S zooepidemicus can migrate from the pharyngeal tonsil to the trachea at a high rate in horses undergoing long distance transportation.  相似文献   
12.
An intradural tumor in the upper cervical region was found in a dog with quadriparesis and chronic respiratory acidosis. Surgical removal of the tumor in the atlas and intraoperative radiotherapy were attempted. The tumor was histologically diagnosed as a neural glioma. A preoperative acid-base disturbance was dramatically improved after surgery. The clinical changes appeared in this case suggest that compression of the spinal cord at this region may cause paralysis of the respiratory muscles and secondarily result in chronic respiratory acidosis following the respiratory insufficiency.  相似文献   
13.
The pathogenic type (form and race) of Fusarium oxysporum, which generates wilt symptoms on tomato, was rapidly identified with a polymerase chain reaction (PCR)-based technique. We compared the partial nucleotide sequences of endo polygalacturonase (pg1) and exo polygalacturonase (pgx4) genes from isolates of F. oxysporum ff. sp. lycopersici (FOL) and radicis-lycopersici (FORL) from Japan and designed specific primer sets (uni, sp13, sp23, and sprl) based on the nucleotide differences that appeared among the pathogenic types. PCR with the uni primer set amplified a 670∼672-bp fragment from all isolates of FOL and FORL. With the sp13 primer set, an amplicon of 445 bp was obtained only from isolates of FOL race 1 and 3. With the sp23 primer set, a 518-bp fragment was obtained from isolates of FOL race 2 and 3. The sprl primer set yielded a 947-bp fragment from isolates of FORL, but not from FOL. A combination of amplifications with these primer sets effectively differentiated the pathogenic types of F. oxysporum in tomato.  相似文献   
14.
The distribution patterns of acetylcholine esterase positive nerve fibers in the goat adrenal gland is described. Some positive cells are observed within the capsule. Terminals were identified in both the medulla and the cortex of the gland.  相似文献   
15.
To clarify mechanisms underlying variation in transpiration rate among deciduous broad-leaved tree species, we measured diurnal changes in stomatal conductance (gs) and leaf water potential, and calculated the maximum transpiration rate (Emax), leaf-specific hydraulic conductance (K(s-l)) and difference between the soil water potential and the daily minimum leaf water potential (Psis - Psi(l,min)). Pressure-volume (P-V) measurements were made on leaves. Saplings of eight broad-leaved tree species that are common in Japanese cool temperate forests were studied. Maximum transpiration rate varied significantly among species. There was a statistically significant difference in Psis - Psi(l,min), but not in K(s-l). Species with large Emax also had large Psis - Psi(l,min) and gs. The results of the P-V analyses showed that species with a large Psis - Psi(l,min) maintained turgor even at low leaf water potentials. The similar daily minimum leaf pressure potentials (Psip) across all eight species indicate that Psip values below this minimum are critical. Based on these results, we suggest that the leaf cell capacity for turgor maintenance strongly affects Psis - Psi(l,min) and consequently Emax via stomatal regulation.  相似文献   
16.
Kraft pulp bleaching effluent supplemented with glucose was decolorized by a newly isolated fungusGeotrichum candidum Dec 1 (Dec 1) that showed a wide decolorizing spectrum to synthetic dyes. When the glucose concentration in the effluent was 30 g/l, the color removal and the reduction of absorbable organic halogens were 78% and 43% after 7 days culture, respectively. The average molecular weight of colored substances measured by gel filtration chromatography was lowered to less than 3000 from 5600 after 7 days culture. As the contribution of extracellular enzymes such as peroxidase (DyP), manganese peroxidase, and laccase to the decolorization of the kraft pulp bleaching effluent was small, Dec 1 appears to have a different mechanism of decolorizing kraft pulp bleaching effluent when compared with enzymes used to decolorize synthetic dyes.  相似文献   
17.
In order to develop a fireproof wooden material, the synergic effect of fire-retardant chemicals and wood coatings was studied. The fire performance was evaluated by cone calorimeter. Impregnation of fire retardants including polyphosphatic carbamate, and ceramic coatings including alkoxy metal salt improved the fire performance of wooden materials. This treatment made it possible to meet the guidelines for fire performance of noncombustible materials in Japan. In addition to the vacuum-pressure impregnation treatment, hot-and-cold-bath impregnation treatment is an effective way to develop fire-retardant wood by impregnating fire retardant and ceramic coating. The weatherability of the developed material was also investigated. The ceramic coating was resistant to light and moisture. Part of this report was presented at 54th Annual Meeting (Sapporo, August 2004) and the 55th Annual Meeting (Kyoto, March 2005) of the Japan Wood Research Society  相似文献   
18.
Poor compatibility was found between exploded wood fiber strand (WFS) and cement due to the excessive presence of water-soluble degraded polysaccharides in extractives of exploded WFS obtained from weathered wood waste treated by the water-vapor explosion process (WVEP). This study presents some comparative results from a continuing investigation on the compressive strengths of exploded WFS–cement mixtures. Based on results previously obtained with the hydration test, the relation between hydration behavior and compressive strength of the mixture was explored. In addition, the effect of the curing age on compressive strength development of the mixture with selected additive chemicals was examined. The results supported the results of early studies with hydration tests indicating that adding MgCl2 to the mixtures of exploded WFS mixed with quick-curing cement or ordinary Portland cement and a composite of MgCl2 + CaO added to the mixture of exploded WFS and furnace-slag cement effectively improved the hydration behaviors; it greatly enhanced the compressive strengths of mixtures as well. Compressive strengths were strongly correlated to maximum hydration temperatures (Tmax) of wood–cement mixtures influenced by the cement type, wood wastes (treated or not with WVEP), additive chemicals, and their content levels. The results also indicated that adding selected chemicals had no significant effect on compressive strength among the mixtures of exploded WFS mixed, respectively, with three types of cement at a curing age of 180 days. X-ray diffraction, scanning electron microscopy, and energy dispersive X-ray spectroscopy were used to identify the hydration products and to probe the element distribution of the mixture in the wood–cement interface zone from a fractured surface.Part of this report was presented at the 52nd Annual Meeting of the Japan Wood Research Society, Gifu, April 2002  相似文献   
19.
To evaluate the effectiveness of sodium bicarbonate (SB) in removing uranium and protecting animals from uranium toxicity, we intramuscularly administered 1 mg/kg of uranyl nitrate to 8-wk-old male SD rats, and 20 min after administration of uranyl nitrate, the animals were given a single oral administration of SB at 0.1, 0.3 or 1 g/kg. The SB treatment at a dose of 0.3 g/kg or more raised the pH of the rats’ urine until 4 h after treatment, and it significantly reduced the uranium amounts in the kidneys at 1 day after treatment. In another experiment, rats were intramuscularly administered 1 mg/kg of uranyl nitrate, and 20 min later, the animals were treated with sodium bicarbonate (0.1 or 1 g/kg). The rats were autopsied at 1, 3 and 7 days after uranium treatment. High-dose SB resulted in a significant increase in urinary uranium excretion in the first 24 h and a reduction of uranium deposition in the kidneys and femurs, and it also significantly suppressed uranium-induced renal toxicity, as shown by both histopathology and clinical chemistry at 3 days after uranium treatment. Low-dose SB did not show such marked effects. Our findings demonstrated that the uranium decorporation effect of sodium bicarbonate was observed at the dosage showing urine alkalinization in rats and that decorporation effect of sodium bicarbonate might be beneficial if it is administered immediately after incorporation of soluble uranium.  相似文献   
20.
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