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81.
Failure to comply with animal welfare requirements during the transport of turkeys to the slaughterhouse increases stress in animals, which is manifested by increased mortality rate during transport. The numbers of turkeys that died during transport or soon after arrival may serve as an important parameter to indicate the level of animal welfare during transport of turkeys. The number of turkeys that died during transport to slaughterhouses in the Czech Republic in the period from 1997 to 2004 was investigated. The mortality rate found was 0.28% +/- 0.06% but varied with travel distance. The lowest mortality rate was found in case of travel distance below 50 km (0.18% +/- 0.08%) while long travel distances resulted in considerable increase in the mortality rates of turkeys (between 0.28% +/- 0.07 and 0.37% +/- 0.10%). The mortality rate of transported turkeys was also affected by the particular month of the year. Thus, the highest overall mortality rate occurred at long travel distances during winter months, i.e. in December (0.34% +/- 0.18%), January (0.32% +/- 0.06%), and February (0.36% +/- 0.07%). The comparison of individual years has shown a long-term trend towards a decrease in turkeys' mortality during transportation to slaughterhouses from 0.32% in 1998 to 0.20% in 2004. The decrease was statistically significant (Spearman's rank correlation coefficient r = -0.86, p < 0.01). This trend can be evaluated as positive.  相似文献   
82.
The free radical scavenging activity of the water infusions, different organic solvent extracts and some constituents from Ligustrum vulgare and Ligustrum delavayanum leaves was assessed with the aid of DPPH radical. Among the samples screened, water infusions had the strongest free radical scavenging capacity. From the tested compounds scavenging active flavonoid aglycones are present in the most active chloroform fractions from both leaves samples.  相似文献   
83.
Forty Erwinia amylovora strains originating from different host plants and locations in Serbia and one strain from Montenegro were characterized by conventional, automated and molecular techniques. All strains were Gram-negative, nonfluorescent, facultative anaerobes, oxidase negative, levan positive, produced necrotic lesions followed by bacterial exudate on artificially inoculated immature pear fruits and caused HR on tobacco. Based on carbon source utilization, all strains tested with the Biolog system were identified as E. amylovora. Based on fatty acid profiles all tested strains clustered into three groups in which strains from north Serbia differed from strains isolated in central and south parts of the country. Restriction analysis of genomic DNA using XbaI and PFGE resulted in six different patterns differentiating the strains into six groups. Most of the investigated strains clustered in one group having the pattern type similar to Pt2 group described earlier as dominant in East Europe and the Mediterranean region. Two strains showed PFGE pattern similar to the previously described Pt3 pattern and one strain had pattern similar to Pt6. Based on size and number of the bands, new restriction patterns, assigned as Pt7, Pt8 and Pt9 were observed. PFGE results showed that the E. amylovora population in Serbia is not homogenous and was possibly introduced from different directions. This is the first characterization of E. amylovora collection of strains from Serbia using fatty acid analysis and PFGE.  相似文献   
84.
BACKGROUND: Quinclorac (3,7-dichloro-quinoline-carboxylic acid) is a selective herbicide widely used to control annual grasses and certain broadleaf weeds. Echinochloa phyllopogon (Stapf) Koss. is the most noxious grass weed in California rice fields and has evolved resistance to multiple herbicides with different modes of action. A quinclorac-resistant (R) E. phyllopogon biotype found in a Sacramento Valley rice field where quinclorac has never been applied was investigated. RESULTS: Resistant to susceptible (S) GR50 (herbicide rate for 50% growth reduction) ratios ranged from 6 to 17. The cytochrome P450 inhibitor malathion (200 mg L−1) caused R plants to become as quinclorac susceptible as S plants. Quinclorac rapidly (6 HAT) stimulated ethylene formation in S plants, but only marginally in R plants. Malathion pretreatment did not reduce ethylene formation by quinclorac-treated S and R plants. Activity of β-cyanoalanine synthase (β-CAS) in tissue extracts was 2-3-fold greater in R than in S plants, and incubation of shoot extracts with 1 mM malathion reduced β-CAS activity by 40% in both biotypes. CONCLUSION: Resistance to quinclorac in R E. phyllopogon involved at least two mechanisms: (a) insensitivity along the response pathway whereby quinclorac induces ethylene production; (b) enhanced β-CAS activity, which should enable greater HCN detoxification following quinclorac stimulation of ethylene biosynthesis. This unveils new resistance mechanisms for this multiple-resistant biotype widely spread throughout California rice fields. Copyright © 2011 Society of Chemical Industry  相似文献   
85.
欧盟委员会 2 0 0 0年底关于在饲料中禁用某些动物蛋白质制品的决定 ,从技术上和经济上对进行猪、禽饲料配合的商业营养师提出了相当严峻的挑战。有些欧洲国家还已经自主决定将鱼粉包括在禁用之列 ,或者因靠近反刍畜饲料生产场地而担心其储存问题故将其剔除出生产多畜种饲料的饲料厂。与此同时 ,许多饲料生产商还往往不用动物脂肪而改用植物油脂以图在越来越严格的监督下增强行业的自信。这些措施的结果是增强了在日粮中对各种植物蛋白质的依赖 ,而究竟选用哪些原料就取决于相对成本和其供应量充足与否。这些原料的纤维含量较高 ,其中蛋白质…  相似文献   
86.
The mechanism of the hypocholesterolemic effect of olive oils was investigated in 60 Wistar rats adapted to cholesterol-containing and cholesterol-free diets. The rats were divided in six diet groups of 10. The control group was fed only basal diet (BD), which contained wheat starch, casein, cellulose, and mineral and vitamin mixtures. For the five other groups, 10 g/100 g virgin (virgin group) or lampante (lampante group) olive oils, 1 g/100 g cholesterol (chol group), or both cholesterol and oil (chol/virgin and chol/lampante groups) were added to the BD. The experiment lasted 4 weeks. Before and after the experiment the bile was collected, and its flow and biliary bile acids and cholesterol concentrations were registered. Plasma lipids, liver cholesterol, plasma antioxidative potential (TRAP), fecal output, fecal bile acids, and fecal cholesterol excretion were measured. Groups did not differ before the experiment. After the experiment significant hypocholesterolemic and antioxidant effects were registered mainly in groups of rats fed cholesterol-containing diets supplemented with both olive oils (chol/virgin and chol/lampante). Significant increases in the bile flow and in the bile cholesterol and bile acids concentrations were observed (19.2% and 16.9%, 30.5% and 18.2%, and 79.6% and 45.6% for the chol/virgin and chol/lampante groups, respectively). Also, significant increases of the fecal output and fecal excretion of bile acids and cholesterol in rats of these groups were found. In conclusion, olive oils positively affect plasma lipid metabolism. The hypocholesterolemic effect of olive oils is genuine and is most likely mediated through increases in bile flow and biliary cholesterol and bile acids concentrations and subsequent increases in their fecal excretion.  相似文献   
87.
Ground fruits of the common juniper (Juniperus communis L.), with a particle size range from 0.250-0.400 mm, forming a bed of around 20.00 +/- 0.05 g, were extracted with supercritical CO(2) at pressures of 80, 90, and 100 bars and at a temperature of 40 degrees C. The total amount of extractable substances or global yield (mass of extract/mass of raw material) for the supercritical fluid extraction process varied from 0.65 to 4.00% (wt). At each investigated pressure, supercritical CO(2) extract fractions collected in successive time intervals over the course of the extraction were analyzed by capillary gas chromatography, using flame ionization (GC-FID) and mass spectrometric detection (GC-MS). More than 200 constituents were detected in the extracts, and the contents of 50 compounds were reported in the work. Dependence of the percentage yields of monoterpene, sesquiterpene, oxygenated monoterpene, and oxygenated sesquiterpene hydrocarbon groups on the extraction time was investigated, and conditions that favored the yielding of each terpene groups were emphasized. At all pressures, monoterpene hydrocarbons were almost completely extracted from the berries in the first 0.6 h. It was possible to extract oxygenated monoterpenes at 100 bar in 0.5 h and at 90 bar in 1.2 h. Contrary to that, during an extraction period of 4 h at 80 bar, it was possible to extract only 75% of the maximum yielded value of oxygenated monoterpene at 100 bar. Intensive extraction of sesquiterpenes could be by no means avoided at any pressure, but at the beginning of the process (the first 0.5 h) at 80 bar, they were extracted about 8 and 3 times slower than at 100 and 90 bar, respectively. Oxygenated sesquiterpenes were yielded at fast, constant extraction rates at 100 and 90 bar in 1.2 and 3 h, respectively. This initial fast extraction period was consequently followed by much slower extraction of oxygenated sesquiterpenes.  相似文献   
88.
Purge and trap injector (PTI) with high resolution gas chromatography (HRGC) was used to determine the concentration levels of volatile organic compounds (VOCs) in water and sediments from the Morava and the Danube Rivers. Thus the average concentrations of volatile n-alkanes (C6-C13) in water and sediments were found to be 0.02—1.33 μg/l and 0.04–105 μg/kg wet weight respectively. While the average concentrations of volatile aromatics in water and sediments were found to be 0.07–3.62 μg/l and 0.08–290 μg/kg wet weight respectively. In general different concentration levels were found at different locations, and at different time periods. With PTI-HRGC small sample size (5–20 ml) of water and (10–20 g) of sediments were used to analyse the VOCs in a simple, rapid method, with low background contamination since the system is completely closed. Relatively higher concentrations of VOCs were found in water and sediment samples from the Morava in comparison with those from the Danube, and higher concentration levels were found in spring time than in summer time.  相似文献   
89.
Headwater streams channelized for water transport of timber in Finland are being restored to their pre-channelization state. The primary motivation is the enhancement of sport fisheries, but restoration probably has profound impacts also on other stream organisms. We assessed how such “single-goal” restorations affect benthic macroinvertebrate communities. We revisited the streams sampled by Laasonen et al. [Aquatic Conservation: Marine and Freshwater Ecosystems 8 (1998)] in the early 1990s when the streams had been recently restored. In 1997, the recovery period of these streams ranged from 4 to 8 years. Habitat structure among the stream types represented a distinct recovery gradient, with streams restored 1 month before sampling and natural streams being the endpoints of a gradient in moss cover (highest in natural, lowest in recently restored streams). Channelized streams supported a characteristic set of indicator species, whereas shifts in species composition between restored and natural streams were more gradual. Macroinvertebrate communities in unmodified streams changed little between the two surveys, whereas communities in restored streams had undergone considerable changes. In-stream restoration is an unpredictable disturbance, to which stream biota cannot have any evolved responses. Therefore, the relatively rapid recovery of habitat structure and macroinvertebrate communities in restored streams is encouraging. However, long-term monitoring of benthic communities in both restored and natural streams is needed to assess whether restoring rivers by these techniques will enhance the recovery of benthic biodiversity in boreal streams.  相似文献   
90.
Seven hybridoma clones, E2/G2, E2/B5, E4/C2, G5/E10, F6/C10, B5/C3, and B7, produced within one fusion experiment in 1991 and the clone E4/C2 originated from 1995 were characterized by sequencing of genes coding for variable domains of the antibodies against 2,4-D herbicide. Amino acid sequences of selected antibodies, deduced from DNA analysis, were confirmed by mass spectrometry. Surprisingly, nucleotide sequence analysis of the clones E2/G2 and E2/B5, producing the most sensitive antibodies, proved to have sequence homology of their variable domains, although the IC(50) values determined for these antibodies 9 years prior to the DNA analysis were 2.0 and 8.2 ng/mL, respectively. The same findings arose from the comparison of the immunochemical to DNA data established for G5/E10, F6/C10, and B5/C3 clones producing antibodies with IC(50) values in the range of 26.3-43.1 ng /mL. The clone E4/C2, originating from the later fusion experiment, did not share nucleotide homology with any of the examined clones. Data obtained by ELISA, immunosensor, and DNA analysis within a 9 year period are discussed with respect to hybridoma stability, methodic artifacts, measurement reliability, and other possible factors influencing the result interpretation.  相似文献   
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