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141.
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143.
Specific binding activity of isolated light chains of antibodies   总被引:2,自引:0,他引:2  
Free light chains isolated from specifically purified antibody have been shown to bind specific hapten. This proves that part of the binding site does exist on the light chain. The light chains were obtained from antibody directed against the 4-azonaphthalene-1-sulfonate group, and the binding of the simple hapten 4-anilinonaphthalene-1-sulfonate was determined by the fluorescence-enhancement technique. Since this hapten undergoes a striking increase in fluorescence on binding to light chains (and also on binding to specific antibody), the presence of small amounts of bound hapten could be determined, even in the presence of the high concentrations of unbound hapten required because of the low binding constant.  相似文献   
144.
Toxic dinoflagellate Alexandrium spp. produce saxitoxins (STXs), whose biosynthesis pathway is affected by temperature. However, the link between the regulation of the relevant genes and STXs’ accumulation and temperature is insufficiently understood. In the present study, we evaluated the effects of temperature on cellular STXs and the expression of two core STX biosynthesis genes (sxtA4 and sxtG) in the toxic dinoflagellate Alexandrium catenella Alex03 isolated from Korean waters. We analyzed the growth rate, toxin profiles, and gene responses in cells exposed to different temperatures, including long-term adaptation (12, 16, and 20 °C) and cold and heat stresses. Temperature significantly affected the growth of A. catenella, with optimal growth (0.49 division/day) at 16 °C and the largest cell size (30.5 µm) at 12 °C. High concentration of STXs eq were detected in cells cultured at 16 °C (86.3 fmol/cell) and exposed to cold stress at 20→12 °C (96.6 fmol/cell) compared to those at 20 °C and exposed to heat stress. Quantitative real-time PCR (qRT-PCR) revealed significant gene expression changes of sxtA4 in cells cultured at 16 °C (1.8-fold) and cold shock at 20→16 °C (9.9-fold). In addition, sxtG was significantly induced in cells exposed to cold shocks (20→16 °C; 19.5-fold) and heat stress (12→20 °C; 25.6-fold). Principal component analysis (PCA) revealed that low temperature (12 and 16 °C) and cold stress were positively related with STXs’ production and gene expression levels. These results suggest that temperature may affect the toxicity and regulation of STX biosynthesis genes in dinoflagellates.  相似文献   
145.
Journal of Soils and Sediments - Urban roadside soils are important growth media for roadside trees. However, typical assessment variables are limited in describing the characteristics of roadside...  相似文献   
146.
A 10‐wk feeding experiment was conducted to evaluate the potential use of fermented soybean curd residues (FSCR) as an energy source in diets for juvenile olive flounder, Paralichthys olivaceus. Five isonitrogenous and isoenergetic diets were formulated to contain dry soybean curd residues to replace wheat meal (WM) at the levels of 0, 25, 50, 75, and 100% (FSCR0, FSCR25, FSCR50, FSCR75, and FSCR100, respectively). Fish averaging 6.00 ± 0.07 g (mean ± SD) were randomly distributed into 15 aquaria as groups of 15 fish and fed the experimental diets in triplicate at a rate of 4–5% of wet body weight per day twice daily on dry matter basis. At the conclusion of the feeding trial, weight gain (WG) and specific growth rate (SGR) of fish fed diet FSCR25 were significantly higher than those of fish fed diets FSCR50, FSCR75, and FSCR100 (P < 0.05); however, there were no significant differences in WG and SGR among fish fed diets FSCR0 and FSCR25 and among those fed diets FSCR0 and FSCR50. Feed efficiency and protein efficiency ratio of olive flounder fed diet FSCR25 were significantly higher than those of fish fed diets FSCR50, FSCR75, and FSCR100 (P < 0.05); however, there were no significant differences in these parameters among fish fed diets FSCR0 and FSCR25 and among those fed diets FSCR0, FSCR50, FSCR75, and FSCR100. Hematological characteristics, condition factor, hepatosomatic index, and survival rate of fish fed FSCR0 were not significantly different from those of fish fed the other diets. These results indicated that FSCR could replace up to 50% WM as an energy source in juvenile olive flounder diets based on ANOVA test.  相似文献   
147.
Some effects of dietary medicinal herbs mixture (HM), Massa medicata fermentata, Crataegi fructus, Artemisia capillaries, and Cnidium officinale, in the proportions 2∶2∶1∶1 were identified in juvenile Japanese flounder Paralichthys olivaceus. In an 8-week feeding trial, fish were fed with 0.1, 0.3, 0.5, and 1.0% HM in a moist diet composed of horse mackerel and an artificial diet in equal parts. Fish fed the diets with 0.3, 0.5, and 1.0% HM showed higher weight gain and feed efficiency than fish in 0.1 and 0% HM feed groups. No significant differences were found in survival, feed intake, final carcass proximate composition, hemoglobin and hematocrit levels, plasma total cholesterol level, and alanine aminotransferase activity among the dietary treatments. Fish fed with 0.3, 0.5, and 1.0% HM showed higher total carcass unsaturated fatty acid content and docosahexaenoic acid (22∶6n−3) level, and plasma high density lipoprotein-cholesterol level, but lower carcass saturated fatty acid content and plasma aspartate aminotrasferase activities than the control group. Moreover, a 10-min air exposure test with five times repeat, and an anesthesia test for 2 min with 200 p.p.m. 2-phenoxyethanol, also revealed lower mortality and lower recovery time in 0.3, 0.5, and 1.0% HM groups than the control group at the end of the trial. These results indicate that the medicinal herb mixture is useful to improve growth, fatty acid utilization, and stress recovery in the Japanese flounder.  相似文献   
148.
This experiment was conducted to study the effects of the graded recombinant bovine somatotropin (rBST) levels on growth, plasma rBST concentrations, and body composition of Korean rockfish, Sebastes schlegeli, and to estimate the optimum oral dosage of rBST. Seven experimental diets were formulated to be isonitrogenous and isocaloric and to contain 49.0% crude protein and 16.7 kJ available energy/g, with 0, 5, 10, 15, 20, 25, or 50 mg rBST/kg body weight (BW)/wk (rBST0, rBST5, rBST10, rBST15, rBST20, rBST25, and rBST50, respectively). After the feeding trial, fish fed all the diets supplemented with rBST showed higher weight gain (WG), feed efficiency (FE), specific growth rate (SGR), and protein efficiency ratio (PER) than those fed the rBST0 diet (P < 0.05). WG of fish fed rBST15, rBST20, rBST25, and rBST50 diets was significantly higher than that of fish fed rBST0 and rBST5 diets (P < 0.05); however, there were no significant differences among fish fed rBST10, rBST15, rBST20, rBST25, and rBST50 diets. FE of fish fed rBST15 and rBST20 diets was significantly higher than that of fish fed rBST0, rBST5, rBST10, and rBST50 diets, and fish fed rBST10, rBST25, and rBST50 diets had significantly higher FE than those fed rBST0 and rBST5 diets (P < 0.05). SGR of fish fed all the diets supplemented with rBST was significantly higher than that of fish fed rBST0 diet (P < 0.05); however, there were no significant differences among fish fed all the diets supplemented with rBST. PER of fish fed rBST15 and rBST20 diets was significantly higher than that of fish fed rBST0, rBST5, and rBST50 diets, and fish fed rBST10, rBST25, and rBST50 diets had significantly higher PER than those fed rBST0 and rBST5 diets (P < 0.05). Whole‐body protein of fish fed rBST15 diet was significantly higher than that of fish fed rBST0, rBST5, and rBST10 diets (P < 0.05); however, there were no significant differences among fish fed rBST15, rBST20, rBST25, and rBST50 diets. Plasma rBST concentrations of fish fed all the diets began to rise at 3 h after oral administration of rBST; the maximum plasma rBST concentration peaked at 12 h and returned to the basal level at 24 h. Broken‐line model analyses of WG and FE were 12.8 and 13.2 mg rBST/kg BW/wk, respectively. These results indicated that the optimum oral dosage could be greater than 12.8 mg rBST/kg BW/wk but less than 13.2 mg rBST/kg BW/wk in juvenile Korean rockfish.  相似文献   
149.
We evaluated the potential ability of germanium biotite (GB) to stimulate the production of antibodies specific for foot-and-mouth disease virus (FMDV). To this aim, we measured the total FMDV-specific antibody responses and IgM production after vaccination against FMD both experimentally and in the field. GB supplementation with FMDV vaccination stimulated the production of anti-FMDV antibodies, and effectively increased IFN-γ and TNF-α levels. These results suggest that GB may be a novel alternative feed supplement that can serve as a boosting agent and an immunostimulator for increasing the efficacy of FMDV vaccination in pigs.  相似文献   
150.
Simple methods for measuring the levels of serum antibody against canine distemper virus (CDV) would assist in the effective vaccination of dogs. To develop an enzyme-linked immunosorbent assay (ELISA) specific for CDV, we expressed hydrophilic extra-viral domain (HEVD) protein of the A75/17-CDV H gene in a pET 28a plasmid-based Escherichia (E.) coli vector system. Expression was confirmed by dot and Western blotting. We proposed that detection of E. coli-expressed H protein might be conformation-dependent because intensities of the reactions observed with these two methods varied. The H gene HEVD protein was further purified and used as an antigen for an ELISA. Samples from dogs with undetectable to high anti-CDV antibody titers were analyzed using this HEVD-specific ELISA and a commercial CDV antibody detection kit (ImmunoComb). Levels of HEVD antigenicity measured with the assays and immunochromatography correlated. These data indicated that the HEDV protein may be used as antigen to develop techniques for detecting antibodies against CDV.  相似文献   
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