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551.
  1. The aims of the present study were to examine whether collagen exists in egg, particularly in egg yolk; to establish a Fourier transform-near infrared (FT-NIR) measurement method for collagen in egg and to assess the possibility of increasing the collagen content by feeding hens a diet containing wood charcoal powder containing wood vinegar liquid (WCV).

  2. The collagen in eggs from 67-week-old hens fed on the dietary 0 and 9.9 g/kg WCV diets was investigated using a combination of histochemical, matrix-assisted laser desorption ionisation with time-of-flight mass spectrometry (MALDI-TOF MS), Fourier transform infrared (FT-IR) and FT-NIR approaches.

  3. All approaches used to identify collagen in egg yolk yielded positive results.

  4. The collagen in egg yolk measured using colorimetry, collagen in egg yolk, egg white and eggshell membrane using FT-NIR and collagen in egg yolk determined by treating the egg yolk with collagenase were abundant after feeding a dietary WCV (p<0.05).

  5. These results suggest that egg yolk contains collagen, that the collagen in egg can be measured using FT-NIR, and that the collagen content of egg yolk can be increased by feeding dietary WCV diets.

  相似文献   
552.
Experiments on alkaline hydrogen peroxide treatments with stepwise addition and oxygen pressurization were performed to determine whether they enhance the reaction between pulp components and hydroxyl radicals produced by the decomposition of hydrogen peroxide. In this study the degradation of methyl-dglucopyranoside (MGP), a model compound of pulp components, was an indicator of the progression of the reaction between pulp components and hydroxyl radicals. When comparing the degradation of MGP in the stepwise and one-time addition systems, MGP was degraded more in the stepwise addition system than in the one-time addition system when Fe3+ was added. This result indicates that the hydroxyl radical produced by the decomposition of hydrogen peroxide efficiently attacks MGP in the stepwise addition system. MGP was degraded to the same degree in the stepwise addition system as in the one-time addition system when Fe2+ or Mn2+ was added. Aggregation and precipitation of metal ions might affect their catalysis. Oxygen-pressurized hydrogen peroxide treatment caused almost no enhancement of the degradation of MGP compared to the treatment under atmospheric pressure. Instead, high stability of hydrogen peroxide was produced by oxygen-pressurized hydrogen peroxide treatment. Such high stability can result in frequent attacks of the hydroperoxide anion, the conjugate base of hydrogen peroxide, against some chromophores and quinones.Part of this paper was presented at the 1998 International Pulp Bleaching Conference, Helsinki, Finland  相似文献   
553.
554.
Interspecific protoplast fusion between two monokaryotic strains (a methionine auxotrophic and chloramphenicol-resistant Pleurotus ostreatus strain and a wild-type strain of Pleurotus pulmonarius) was carried out to introduce mitochondrial DNA (mtDNA) from P. ostreatus into P. pulmonarius. Because mycelial colonies regenerated on minimum medium containing chloramphenicol only after the treatment of protoplast electrofusion, the regenerants were regarded as protoplast fusants. The fusants isolated from regenerated colonies were uninucleate, and their resistance of chloramphenicol seemed to be a stable trait. The fusants mated with P. pulmonarius but not with P. ostreatus, and showed almost identical random amplified polymorphic DNA (RAPD) patterns to that of the parental P. pulmonarius monokaryon. The sizes of mitochondrial genomes were estimated to be 81.5 kb for P. ostreatus monokaryon, 54.9 kb for P. pulmonarius monokaryon, and 84.5 or 86.0 kb for the fusants. BamHI and EcoRI digest patterns of the fusant mtDNAs were almost the same as the parental P. ostreatus monokaryon. From the above results, the fusants seemed to carry nuclei derived from the monokaryon of P. pulmonarius and mtDNA including the chloramphenicol-resistance gene from the P. ostreatus monokaryon, suggesting that the P. ostreatus mtDNA had been introduced into P. pulmonarius cells by interspecific protoplast fusion. Contribution No. 383 of the Tottori Mycological Institute  相似文献   
555.
To analyze the structural features of lignin in the vicinity of lignin–carbohydrate linkages, water-soluble lignin–carbohydrate complex (LCC) with low lignin content was prepared from residual birch wood meal after the extraction of milled wood lignin (MWL). The molecular weight distribution of lignin in this LCC appeared together with carbohydrate in the relatively high molecular weight region of the gel permeation chromatogram. This result was consistent with our previous results obtained for the same fraction of Japanese cedar (sugi); however, after treatment with polysaccharide-degrading enzyme, the molecular weight distribution of carbohydrate and that of lignin shifted significantly to the lower region. These results demonstrated that molecular size of this LCC is determined by carbohydrates while lignin is present as a minor fragment in this fraction. The syringyl/guaiacyl (S/V) ratio of this LCC was higher than other lignin fractions. Ozonation analysis implied that this LCC has a relatively high number of β-1 structures. It is likely that lignin that exists near lignin–carbohydrate linkages has more endwise-type features than other lignin fractions.This paper was presented in part at the 48th Lignin Symposium, Fukui, Japan, October 2003 and at the 12th International Symposium on Wood and Pulping Chemistry, Madison, USA, June 2003  相似文献   
556.
We explored the relationship between directional variation (changes in direction from a reference point) in vegetation and wind profiles, and propose an empirical wind profile model that may reproduce the wind profile within the canopy (such as secondary wind maximum) and reduce calculation loads. Based on the results of our observations in secondary broad-leaved forest, we clarified the variation in secondary wind maximum and aerodynamic parameters in wind direction, and assessed the influence of forest structural heterogeneity on the wind profile. Wind blew from specific directions depending on the time of day and season, and secondary wind maxima were observed in particular wind directions. Outlier estimations of aerodynamic parameters were determined for wind directions of 45°, 120–210°, and 300°, and these did not show a logarithmic distribution. Our proposed model reproduced the wind profile within and above the canopy, closely resembling K-theory and closure models, and reduced the required number of calculations and observations. The influence of forest structural heterogeneity was greatest in the upper part of the canopy (9.14 m), and reproducibility of the wind profile was improved by 0.05 m/s (3.4% on average) by changing the forest structural parameters of the model according to the wind direction. It was clear that forest structural heterogeneity did not cause critical errors in estimation of the wind profile, even at our study site, which had complex forest structure.  相似文献   
557.
A novel method for analysis of benzylic ether type lignin–carbohydrate bonds has been developed by using model compounds. Four diastereomers of model compound 3-(4-hydroxy-3-methoxyphenyl)-2-(2-methoxyphenoxy)-3-(methyl -d-glucopyranoside-6-O-yl)-1-propanol (GGMGP), were ozonized in acetic acid/water/methanol 16:3:1 for 1h at 0°C. The product from ozonation of each diastereomer was saponified and the corresponding -etherified tetronic acid (TAMGP) was isolated using ion exchange chromatography. Minor amounts of methyl -d-glucopyranoside (MGP) and small amounts of a gluconic acid etherified with tetronic acid (TAGLCA), tetronic acid, gluconic acid, and glyceric acid were detected in the product mixture of ozonated benzylic ether type model compounds. The results suggest that a benzyl ether bond between lignin and carbohydrate is rather stable during the ozone treatment. Acid treatments with sulfuric acid or trifluoroacetic acid of the derived TAMGP led to cleavage of the glucosidic bond but only a small amount of products (tetronic acid and glucose) resulting from cleavage of the -ether bond were formed. The successful chemical treatments were used for studies of benzylic ether bonds in Japanese red pine. The results suggest the presence of benzylic ether bonds to polysaccharides in the wood.Part of this paper was presented at the 10th International Symposium of Wood and Pulping Chemistry (ISWPC), Yokohama, 1999; the 11th ISWPC, Nice, 2001; and as a rapid comunication in J Wood Sci (2000) 46:263–265  相似文献   
558.
Methanol liberation and methoxyl loss during chlorine bleaching of softwood kraft pulp were quantitatively investigated to estimate the degree of structural modification of lignin aromatics. An increase in the chlorine multiple led to enhanced methoxyl loss from lignin. Our result, using pH-adjusted chlorine water (pH 5.7), by which chlorination under oxidation-favorable conditions was achieved, strongly supported the importance of the oxidation reaction by chlorine during delignification and lignin degradation. It was also suggested that methanol can be produced not only via catalytic hydrolysis by chlorine but via oxidative cleavage of the ether bond as well. The infrared spectrum of chlorolignins suggested that chlorine oxidation can open aromatic rings to muconic acid derivatives without cleaving ether bonding of the methoxyl group. No straight relation between the methoxyl content and the kappa number of chlorinated pulps was shown. The methoxyl content of bleached kraft pulps subjected to successive chlorination and alkali extraction showed a good relation with the kappa number. This means that almost all the portions of the oxidatively modified lignin structure were successfully removed during these treatments, and the aromatic structures of residual lignin in chlorinated and alkali-extracted pulps were thought to remain intact.Part of this paper was presented at the 46th Annual Meeting of the Japan Wood Research Society, Kumamoto, April 1996; the 10th International Symposium on Wood and Pulping Chemistry, Yokohama, June 1999; and the 67th Pulp and Paper Research Conference, Tokyo, June 2000  相似文献   
559.
A 90-day oral toxicity test in rats was performed to evaluate the toxicity of 2-tetradecylcyclobutanone (2-tDCB), a unique radiolytic product of stearic acid. Six-week-old male and female F344 rats (n=15/group) were given 2-tDCB at concentrations of 0, 12, 60 and 300 ppm in a powder diet for 13 weeks. Slight dose-dependent increases in serum total protein and albumin in male rats were found, but these changes were not considered to be a toxic effect. The fasting, but not non-fasting, blood glucose levels of the male rats in the 300 ppm group and female rats in the 60 and 300 ppm groups were lower than those of the controls. Gas chromatography-mass spectrometry analysis showed dose-dependent accumulation of 2-tDCB in adipose tissue, notably in males. Next, we performed an azoxymethane (AOM)-induced two-stage carcinogenesis study. After injection of 6-week-old male F344 rats (n=30/group) once a week for 3 weeks, the animals received 2-tDCB at concentrations of 0, 10, 50 and 250 ppm in a powder diet for 25 weeks. The incidences of colon tumors for the 2-tDCB dosages were 34%, 45%, 40% and 37%, respectively, and were not statistically significant. These data suggest that 2-tDCB shows no toxic or tumor-modifying effects under the present conditions, and that the no-observed-adverse-effect level for 2-tDCB is 300 ppm in both sexes, equivalent to 15.5 mg/kg b.w./day in males and 16.5 mg/kg b.w./day in females.  相似文献   
560.
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