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101.
《Phytomedicine》2014,21(11):1466-1472
PurposePropolis biological effects are mainly attributed to its polyphenolic constituents such as flavonoids and phenolic acids that were recently described in the chemical composition of an extract of propolis obtained with edible vegetal oil (OEP) by our group. The aim of this study was to evaluate the effect of OEP on the behavior of rats.Materials and methodsAn in vivo open field (OF), elevated Plus-maze (EPM), and forced swimming (FS) tests were performed to evaluate locomotor activity, anxiolytic- and antidepressant effects of the extract. Besides, oxidative stress levels were measured in rat blood samples after the behavioral assays by evaluation of the Trolox equivalent antioxidant capacity (TEAC) and nitric oxide levels.ResultsOEP increased locomotion in the OF test (50 mg/kg) and central locomotion and open arm entries in the OF and EPM tests (10–50 mg/kg) and decreased the immobility time in the FS test (10–50 mg/kg). Moreover, OEP reduced nitric oxide levels in response to swim stress induced in rats.ConclusionOEP exerted stimulant, anxiolytic and antidepressant effects on the Central Nervous System and antioxidant activity in rats, highlighting propolis as a potential therapeutic compound for behavior impairment of anxiety and depression. 相似文献
102.
Arthur H. L. From Dwight S. Fullerton Khalil Ahmed 《Molecular and cellular biochemistry》1990,94(2):157-165
The structure-activity relationships of the genin moieties of digitalis glycosides are commonly elucidated by determining the inhibitory potency of a variety of genins toward the plasma membrane Na+, K+-ATPase; qualitatively these relationships appear to be fairly independent of the specific Na+, K+-ATPase preparation utilized for the analysis. To determine whether this is the case with regard to the sugar moieties of glycosides, the inhibitory effects of 12 monoglycosides of digitoxigenin toward four Na+, K+-ATPase preparations of different origin were measured. It was found that while recognition of the major structural determinants of sugar activity appeared to be independent of enzyme source, recognition of the minor structural determinants of activity showed some source dependence. It was also observed that the intrinsic sensitivity to sugar potentiation may be source dependent and unrelated to intrinsic sensitivity to inhibition by digitoxigenin. These observations are compatible with a model of the Na+, K+-ATPase sugar binding site(s) in which intrinsic sensitivity to sugar attachment as well as recognition characteristics (for sugar structural features) both determine the extent to which a sugar moiety may contribute to the activity of monoglycosides. Further, in these studies one of the Na+, K+-ATPase preparations employed was obtained from rat brain, a tissue known to contain a mixture of ouabain sensitive and insensitive isoforms. We have observed that the rigorous purification techniques employed appear to have selectively removed from or denatured the less ouabain sensitive al isoform found in this enzyme preparation. 相似文献
103.
用酸浸提、酒精沉淀法,从桔皮中提取果胶,通过正交设计分析,获得最佳得率的工艺条件。即果胶浸提液的酸度为pH2,反应时间2小时。沉淀果胶的酒精浓度为50%,其得率是12.6%。 相似文献
104.
Genetics of alcohol dehydrogenase in Saccharomyces cerevisiae: I. Isolation and genetic analysis of adh mutants 总被引:1,自引:0,他引:1
M. Ciriacy 《Mutation research》1975,29(3):315-325
On the basis of allyalcohol resistance, Saccharomyces cerevisiae mutanta were isolated that were deficient in alcohol dehydrogenase (ADH). The mutants were divided into three classes by their different ADH isozyme pattern obtained after starch-gel electrophoresis: adc mutants that did not produce the constitutive ADH, adr mutants from which the glucose repressible enzyme (ADHII) was absent, and adm mutants deficient in ADH activity associated with the mitochondria.Genetic analysis showed that two genes control synthesis of the glucose repressible enzyme ADHII, one gene the constitutive ADHI and a fourth nuclear gene the mitochondrial ADH. None of these four genes showed any linkage.The various mutant types did not show drastic effects on yeast growth on media containing glucose or ethanol as sole carbon sources. 相似文献
105.
Li HeXiaoyan Chen Muke ZhouDongping Zhang Jie YangMi Yang Dong Zhou 《Phytomedicine》2011,18(6):437-442
Agents of sanchi have been widely used as a complementary medicine for stroke in China. Sanchitongshu is a new Chinese patent medicine extracted from sanchi which has stronger anti-platelet activity than other agents of sanchi. Our aim was to investigate the synergistic action of low dose of aspirin combined with sanchitongshu capsule in the treatment of patients with light and moderate ischemic stroke in acute and subacute stages.This was a multi-center, double-blinded, randomized controlled clinical trial conducted in four hospitals in China from July 2004 to 2006. 140 patients of ischemic stroke in anterior cerebral circulation within 30 days of onset were enrolled. Participants were assigned either to receive aspirin (50 mg per day) and sanchitongshu capsule (200 mg three times a day) or aspirin (50 mg per day) and placebo capsule.Low dose of aspirin combined with sanchitongshu capsule significantly ameliorated neurological deficit (increased score of ESS: t = −5.02, p < 0.0001) and activities of daily living (increased score of BI: t = −2.4, p = 0.0178) after treatment compared with aspirin alone. Adverse reaction which occurred equally in both arms, was light to moderate and disappeared without special treatment.Sanchitongshu capsule, as a complementary medicine to aspirin, was effective in improving outcomes after ischemic stroke. It was a safe drug in our trial. 相似文献
106.
裸花紫珠是海南一种道地药材,具有消炎止血的功效。裸花紫珠富含黄酮类和苯乙醇苷类化学成分,它们已经被证实是天然抗氧化剂的主要来源之一。为了考察裸花紫珠药材的抗氧化活性,该研究采用DPPH.自由基清除法测定裸花紫珠醇提物、4个不同极性部位(石油醚、乙酸乙酯、正丁醇、水)及其7个主要成分的抗氧化作用。结果表明:裸花紫珠醇提物、醇提物的水部位、正丁醇部位、乙酸乙酯部位和化合物木犀草素、木犀草苷、毛蕊花糖苷具有较强的抗氧化活性,而5-羟基-3,7,3′,4′-四甲氧基黄酮的抗氧化活性则较弱。该研究结果为裸花紫珠的保健功能开发提供了依据。 相似文献
107.
108.
Piero Pollesello Renato Toffanin Erminio Murano Roberto Rizzo Sergio Paoletti Bjarne J. Kvam 《Journal of applied phycology》1992,4(2):149-155
Lipid extracts of the red algaGracilaria longa were studied by1H- and13C-NMR spectroscopy. Peaks in the13C-NMR spectra attributable to sterols, chlorophylls and carotenoids allowed free and acylated cholesterol, chlorophylla and lutein to be identified as the most abundant components of these classes. A content of 0.5 ± 0.1 μmoles of total cholesterol/g
wet alga was estimated from the1H-NMR spectrum, which also allowed the determination of the phosphatidylcholine/total lipid molar ratio (9.5 ± 0.5%). The13C-NMR spectroscopic experiments provided information on the position of the double bonds on the fatty acid residues. A comparison
between NMR spectra of lipid extracts obtained for wet and dried alga showed that the alga undergoes both a dramatic peroxidation
and some glycolipid degradation during the drying process. 相似文献
109.
The stereoselective degradation of the racemic benalaxyl in vegetables such as tomato, tobacco, sugar beet, capsicum, and the soil has been investigated. The two enantiomers of benalaxyl in the matrix were extracted by organic solvent and determined by validated chiral high-performance liquid chromatography with a cellulose-tris-(3, 5-dimethylphenylcarbamate)-based chiral column. Rac-benalaxyl was fortified into the soil and foliar applied to vegetables. The assay method was linear over a range of concentrations (0.5-50 microg ml(-1)) and the mean recoveries in all the samples were more than 70% for the two enantiomers. The limit of detection for both enantiomers was 0.05 microg g(-1). The results in soil showed that R-(-)-enantiomer dissipated faster than S-(+)-enantiomer and the stereoselectivity might be caused by microorganisms. In tomato, tobacco, sugar, beet, and capsicum plants, there was significantly stereoselective metabolism. The preferential absorption and degradation of S-(+)-enantiomer resulted an enrichment of the R-(-)-enantiomer residue in all the vegetables. 相似文献
110.
贯叶连翘醇提条件的多指标优化 总被引:6,自引:0,他引:6
本研究采用超声波提取法,对贯叶连翘中总黄酮、金丝桃素类和贯叶金丝桃素等主要有效成分在醇提过程中的提取条件(溶媒种类、浓度、提取时间等)进行了考察。结果表明,以总黄酮和金丝桃素类化合物为指标,用65%~80%的乙醇水溶液超声提取30min,提取效率较高;以贯叶金丝桃素为指标,则以用75%~90%的甲醇提取30min效果较好。 相似文献