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61.
An experiment was carried out to assess the feeding effect of Chinese herbal medicine on N balance, ruminal fermentation characteristics, kinetics of plasma glucose, leucine and energy metabolism in sheep kept at thermoneutral environment (23°C) or exposed to cold (2–4°C). Four sheep were subjected to either mixed hay (MH‐diet) or hay supplemented with 2% of a traditional nourishing Chinese herbal medicine mixture (Astragalus root, Angelica root and Atractylodes rhizome; CHM‐diet) over two 23‐day periods using a crossover design. Cold exposure was conducted for 5 days. The isotope dilution of [U‐13C]glucose with open circuit calorimetry was used to determine the turnover and oxidation rates of plasma glucose and metabolic heat production. The rate of plasma leucine turnover was measured with an isotope dilution method using [1‐13C]leucine. N intake was higher, N excretion through faeces was lower and N digestibility was higher for the CHM‐diet than the MH‐diet. Rumen pH was lower, concentration of rumen NH3 was higher, concentrations of rumen total VFA and acetate tended to be higher and propionate was higher for the CHM‐diet compared with the MH‐diet. Turnover rate of plasma glucose was higher for the CHM‐diet than the MH‐diet and increased during cold exposure. Oxidation rate of plasma glucose did not differ between diets and also between environments. Turnover rate of plasma leucine was higher for the CHM‐diet compared with the MH‐diet but remained similar between environments. Heat production was greater for the CHM‐diet than the MH‐diet and increased during cold exposure. No significant diet × environment interaction was detected. The present results demonstrated that plasma glucose and energy metabolism were enhanced by both Chinese herbal medicine and cold exposure; plasma leucine metabolism was enhanced by Chinese herbal medicine but with lack of change in response to cold exposure in sheep under the conditions of the current experiment.  相似文献   
62.
63.
Production of bioethanol from rice straw has attracted attention from the point of effective use of agricultural residue. Starch content is an important determinant for bioethanol production from rice straw. The overexpression of CO2-responsive CCT protein (CRCT), which is the positive regulator of starch synthesis in vegetative organs, notably increased the starch content in rice straw. To produce the bioethanol from rice straw, the dilute acid pretreatment is a general pretreatment method. Importantly, the glucose yields in liquid hydrolyzate after dilute acid pretreatment was markedly increased in the CRCT overexpression lines compared with non-transgenic rice. In addition, the overexpression of CRCT enhanced the biomass production. In contrast, CRCT did not affect on the glucose yields from cellulose in acid-insoluble residue obtained after dilute acid pretreatment. With respect to byproduct in liquid hydrolyzate which inhibits the fermentation, the formic acid content was increased, whereas the furfural, 5-hydroxymethylfurfural and acetic acid contents were unchanged by the overexpression of CRCT. These results demonstrate that genetic engineering of CRCT is an effective method to increase the bioethanol production from rice straw.  相似文献   
64.
The food habits of 67 fish species collected from the mangrove estuary of the Urauchi River, Iriomote Island, southern Japan were investigated using gut content analysis. Ontogenetic changes in food preference were recognized in nine species, including mugilids, gerreids, mullids, gobiids and tetraodontids. In most cases, juveniles of these species fed mostly on small crustaceans (e.g. calanoid and cyclopoid copepods and gammaridean amphipods) or detritus. With their subsequent growth, larger prey items (e.g. crabs and polychaetes) became dominant. A cluster analysis based on dietary overlaps showed that the mangrove fish assemblage comprised eight trophic groups (zooplankton, small benthic crustacean, large benthic crustacean, polychaete, fish, detritus, plant and insect feeders). Of these, large and small benthic crustacean feeders, which consumed mainly crabs and gammaridean amphipods, respectively, were the most abundantly represented in terms of species, whereas polychaete and insect feeders were each represented by only two species.  相似文献   
65.
This paper presents the performance of coated carbide tools when grooving various density hardboards and wood-chip cement boards. Work materials of low density (about 0.8g/cm3) and high density (about 1.2g/cm3) were tested. The coating materials studied were chromium carbide, titanium carbonitride, and titanium carbide, which were synthesized on P30 carbide substrate using a chemical vapor deposition method; titanium nitride, chromium nitride, and titanium carbonitride were synthesized using the physical vapor deposition method. Cutting tests were performed during grooving at a cutting speed of 1000m/min and a feed rate of 0.1 mm/rev. The results of the study show that the coated carbide tools are more advantageous in reducing the progression of tool wear and retaining lower normal force and noise level when cutting both hardboard and wood-chip cement board of high density than was the uncoated carbide tool. The wear rate of the coated carbide tools for the wood-chip cement board increased more rapidly than that of the hardboard with increasing densities. Though the coated carbide tools suffered more wear with the low-density wood-chip cement board than with hardboard, their normal force and noise level were always lower for the low-density wood-chip cement board.Part of this paper was presented at the 11th Annual Meeting of the Chugoku Shikoku branch of the Japan Wood Research Society, Matsue, Shimane, September 25, 1999  相似文献   
66.
To characterize the mechanism of the reaction of lignin with aqueous acetic acid (AW) containing a small amount of H2SO4, guaiacylglycerol--guaiacyl ether (GOG), and guaiacylglycerol--syringol ether (GOS) were refluxed in 90% AW with 0.28% H2SO4 for 0–120 min. Reaction products and their silylated derivatives were characterized by analytical methods such as gas chromatography-mass spectrometry and nuclear magnetic resonance. When the model compounds were allowed to react at boiling temperature for 0 min (heat-up time 30 min), most of their primary alcohol groups and some of their secondary alcohol groups were acetylated, but their phenolic groups were not. About 90% of GOG was degraded, polymerized, or both during boiling for at least 15 min, yielding guaiacol and isocoumaran compounds (GOG-e and GOG-f) in addition to homovanillin (II) as guaiacylvinyl alcohol (I) and other minor products. GOS yielded syringol, homovanillin (II), and a novel compound (V) together with unknown products but not the corresponding isocoumaran compounds.  相似文献   
67.
The best methods for determining surface roughness in an industrial environment are of the noncontact variety, with reproduction of the profile. The objective of this work was to compare the roughness profile obtained by a contact stylus with a commercial laser displacement sensor (LDS). Measurements were done using 15 wood species with different densities and colors, based on which special triangle profiles were prepared. The accuracy of the laser sensor was examined by statistical analysis of roughness parameters measured from the profiles. Experimental results show that LDS profiles were imitated correctly. However, LDS accuracy depends on the scanned wood properties (density and color), installation position of the sensor, and profile shape. It was found that evaluation of dark and high-density wooden surfaces was imperfect.Part of this work was presented at the 50th Annual Meeting of the Japan Wood Research Society, Kyoto, April 2000; and at the 51st Annual Meeting of the Japan Wood Research Society, Tokyo, April 2001  相似文献   
68.
We examined the abrasive wear properties and the effect of abrasive grain size on the rate of wear when sugi wood (Cryptomeria japonica D.Don), compressed to various densities, was rubbed with abrasive paper. The results showed that the wear resistance of compressed wood increased linearly with the increased compression ratio; and under the condition of a low compression ratio it tended to be higher in comparison with the strength of compressed wood. The critical grain size effect, which can be witnessed during the abrasive wear of metals and plastics, was seen when low pressure was applied to the abrasive material. At higher pressures, the wear rate of the compressed wood increased with grain size, but the critical grain size effect was not observed. The pressure required to create the critical grain size effect was found to be higher than that needed for other types of uncompressed wood with the same yield properties.Part of this report was presented at the 50th Annual Meeting of the Japan Wood Research Society, Kyoto, April 2000  相似文献   
69.
A polymeric amphiphile, PE-AL, was prepared from acetic acid lignin (AL) obtained by acetic acid pulping of birch under atmospheric pressure with polyethylene glycol diglycidyl ether (PE) as the crosslinker. The behavior of PE-AL solutions and the complex formation of PE-AL with protein were investigated to clarify the function of this novel lignin derivative. The reduced viscosity of the amphiphile in aqueous solution was low (<0.3dl/g), and it decreased with increasing concentration in dilute solution. This suggested that the PE-AL in aqueous solution has a structure similar to that of Einstein's sphere and shrinks upon hydrophobic interaction among the structural moieties in AL and the exclusive volume effect. The amphiphilic PE-AL obviously formed a complex with bovine serum albumin (BSA) at 4°C with a reaction time of about 1 week. After complex formation with cellulase for 1 week, the cellulase activity of the resulting complex is significantly enhanced and is preserved after recycling the complex for hydrolysis of cellulosic materials several times.Part of this work was presented at the 48th Annual Meeting of the Japan Wood Research Society, Shizuoka, April 1998  相似文献   
70.
High linear energy transfer (LET) heavy charged particles have previously been applied clinically to human cancer radiotherapy because of their excellent physical properties of selective dose distribution and higher relative biological effectiveness (RBE) for human; however, such an approach has yet to be applied to cat patients. The present study investigates the biological effectiveness of low-LET gamma-rays (0.2 keV/micro m) compared to high-LET carbon ions (114 keV/micro m) in feline T- lymphocyte FeT-J cells. Clonogenic survival analysis revealed that the RBE value of carbon ions was 2.98 relative to a 10% survival dose (D(10)) by gamma-rays, and that the inactivation cross-section in cells exposed to gamma-rays and carbon ions was 0.023 and 38.9 micro m(2), respectively. Terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-biotin nick end labeling (TUNEL) analysis revealed that TUNEL-positive frequency in carbon-irradiation cells is higher than for gamma-irradiated cells against exposure to the same physical doses, but that very little difference in TUNEL-positive frequency is observed between cells exposed to the respective D(10) dose of gamma-rays. Our data thus indicate that carbon ions are more effective for cell killing than gamma-rays at the same physical doses, but kill cells to an extent that is comparable to gamma-rays at the same biological doses. Carbon ion radiotherapy is therefore a promising modality for cat patients.  相似文献   
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