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101.
Background
Isodon rugosus is used traditionally in the management of hypertension, rheumatism, tooth-ache and pyrexia. Present study was arranged to investigate I. rugosus for phytoconstituents, phytotoxic and cytotoxic activities to explore its toxicological, pharmacological potentials and to rationalize its ethnomedicinal uses. Briefly, qualitative phytochemical analysis of the plant extracts were carried out for the existence of alkaloids, flavonoids, saponins, oils, glycosides, anthraquinones, terpenoids, sterols and tannins. Plant crude methanolic extract (Ir.Cr), its subsequent fractions; n-hexane (Ir.Hex), chloroform (Ir.Chf), ethyl acetate (Ir.EtAc), aqueous (Ir.Aq) and saponins (Ir.Sp) in different concentrations were tested for phytotoxic and cytotoxic activities using radish seeds and brine shrimps (Artemia salina) respectively. The phytotoxic activity was determined by percent root length inhibition (RLI) and percent seeds germination inhibition (SGI) while the cytotoxicity was obtained with percent lethality of the brine shrimps.Results
Ir.Cr was tested positive for the presence of alkaloids, glycosides, flavonoids, oils, terpenoids, saponins, tannins and anthraquinones. Among different fractions Ir.Sp, Ir.Chf, Ir.EtAc, and Ir.Cr were most effective causing 93.55, 89.32, 81.32 and 58.68% inhibition of seeds in phytotoxicity assay, with IC50 values of 0.1, 0.1, 0.1 and 52 μg/ml respectively. Similarly, among all the tested samples, Ir.Sp exhibited the highest phytotoxic effect causing 91.33% root length inhibition with IC50 of 0.1 μg/ml. Ir.Sp and Ir.Chf were most effective against brine shrimps showing 92.23 and 76.67% lethality with LC50 values of 10 and 12 μg/ml respectively.Conclusions
It may be inferred from the current investigations that I. rugosus contains different secondary metabolites and is a potential source for the isolation of natural anticancer and herbicidal drug molecules. Different fractions exhibited phytotoxic and cytotoxic activities, thus providing pharmacological basis for ethnomedicinal uses of this plant. 相似文献102.
Adnan Daud Khan Sultan Daud Khan Rehan Ullah Khan Naveed Ahmad 《Plasmonics (Norwell, Mass.)》2014,9(2):461-475
The presence of plasmonic Fano-like resonances in the optical response of isolated and dimer metal-dielectric-metal nanostructures are investigated theoretically. The nanostructures are engineered in such a way to support multiple Fano-like resonances that are induced by the interference of bright and dark plasmon modes. It is found that the dimer resonators exhibit different types of Fano resonances for both the transverse and longitudinal polarizations unlike conventional nanodimers. Several configurations of the dimer Fano resonator are analyzed with special emphasis on the Fano spectral line shape. Breaking the symmetry of the dimer nanostructure in various directions control the asymmetric line shape and provides different kinds of unique Fano resonances. In certain cases, the Fano resonators exhibit multiple Fano resonances that are particularly significant for plasmon line shaping and can serve as platforms for multi-wavelength sensing applications. 相似文献
103.
Nisar Ahmad Bilal Haider Abbasi Hina Fazal Mubarak Ali Khan Muhammad Siddique Afridi 《Comptes rendus biologies》2014,337(1):19-28
In this study, a novel approach for in vitro regeneration of Piper nigrum L. has been applied in order to increase healthy biomass, phytochemicals and piperine production via reverse photoperiod (16hD/8hL). Leaf portions of the seed-derived plants were placed on an MS-medium fortified with different PGRs. Under 16hD/8hL, thidiazuron (TDZ; 4.0 mg L−1) and BA (1.5 mg L−1) was found to be the most effective (< 90%) in callus induction. Two concentrations (1.5, 2.0 mg L−1) of the IBA produced > 80% shoots from callus cultures. Healthy shoots were transferred to rooting medium and higher percentage of rooting (< 90%) was observed on IBA (1.5 mg L−1). These in vitro tissues were subjected to amino acid analysis, spectrophotometry, and HPLC. ARG, SER, THR, and TYR were the most abundant components out of 17 amino acids. Higher amino acid production was observed under normal photoperiod (16hL/8hD) than under reverse photoperiod (16hD/8hL). The highest total phenolic content (TPC; 9.91 mg/g-DW) and flavonoid content (7.38 mg/g-DW) were observed in callus cultures incubated under 16hL/8hD than other tissues incubated under 16hD/8hL photoperiod. Higher DPPH and PoMo activities were observed in tissues incubated under 16hL/8hD photoperiod, while ABTS and Fe2+ chelating activities were found higher in tissues incubated under reverse photoperiod. Significant quantities of piperine content were observed in all tissues except callus cultures. These results suggest that reverse photoperiod is a promising approach for callus induction, phytochemicals and piperine production for commercial applications. 相似文献
104.
105.
Introduction
Early neonatal deaths account for 75% of neonatal deaths globally. Antenatal iron-folic acid (IFA) supplementation has significantly reduced the risk of early neonatal deaths in China and Indonesia. We investigated the impact of antenatal IFA supplements on the risk of early neonatal deaths in Nepal and Pakistan during the last decade.Methods
Data from the most recent singleton live-births of 8,186 from two Nepal Demographic and Health Surveys (DHS) and 13,034 from two Pakistan DHS were selected for the current study. The primary outcome was early neonatal deaths and the main study variable was antenatal IFA supplementation. Analyses used multivariate Cox proportional regression, adjusted for the cluster sampling design and for 18 potential confounders.Findings
The adjusted risk of early neonatal deaths was significantly reduced by 51% (aHR = 0.49, 95% CI = 0.32–0.75) in Nepal and 23% (aHR = 0.77, 95% CI = 0.59–0.99) in Pakistan with any use of IFA compared to none. When IFA supplementation started at or before the 5th month of pregnancy, the adjusted risk of early neonatal mortality was significantly reduced by 53% in Nepal, and 28% in Pakistan, compared to no IFA. When >90 IFA supplements were used and started at or before 5th months, the adjusted risk of early neonatal deaths was significantly reduced by 57% in Nepal, and 45% in Pakistan. In Nepal 4,600 and in Pakistan 75,000 early neonatal deaths could be prevented annually if all pregnant women used >90 IFA supplements and started at or before the 5th month of pregnancy.Conclusions
Any use of IFA supplements was significantly associated with reduced risk of early neonatal deaths in Nepal and Pakistan. The greatest mortality sparing effect of IFA on early neonatal deaths in both countries was with early initiation and use of a greater number of supplements. 相似文献106.
107.
108.
Doriane Richard Ullah Barbe Pedro Bausero 《Biochemical and biophysical research communications》2009,389(3):516-522
We investigated the anti-inflammatory and antioxidant activities of docosahexaenoic acid (DHA) by evaluating its modulation of the two enzymes most involved in vascular inflammation, i.e. endothelial secreted phospholipase A2 (sPLA2) and NADPH oxidase 4 (Nox) 4. Exposure of human aortic endothelial cells (HAECs) to DHA led to its preferential incorporation into outer leaflet phospholipids. Pre-treatment with DHA abolished HAECs stimulation induced by A23187 and Ang II, whereas the effects on IL-1β treatment were less pronounced. Group V sPLA2 RNA was similarly modulated by DHA supplementation. In addition, DHA decreased Nox 4 expression and activity; this effect was associated with reduced production of reactive oxygen species. Further, the use of specific inhibitors allowed demonstrating that group V sPLA2 is involved in the down-regulation of Nox 4 expression and activity by DHA. This interplay is mediated by ERK and PKC. 相似文献
109.
Shuo Liu Thomas L. Dunwell Gerd P. Pfeifer Jim M. Dunwell Ihsan Ullah Yinsheng Wang 《PloS one》2013,8(12)
Epigenetic regulations play important roles in plant development and adaptation to environmental stress. Recent studies from mammalian systems have demonstrated the involvement of ten-eleven translocation (Tet) family of dioxygenases in the generation of a series of oxidized derivatives of 5-methylcytosine (5-mC) in mammalian DNA. In addition, these oxidized 5-mC nucleobases have important roles in epigenetic remodeling and aberrant levels of 5-hydroxymethyl-2′-deoxycytidine (5-HmdC) were found to be associated with different types of human cancers. However, there is a lack of evidence supporting the presence of these modified bases in plant DNA. Here we reported the use of a reversed-phase HPLC coupled with tandem mass spectrometry method and stable isotope-labeled standards for assessing the levels of the oxidized 5-mC nucleosides along with two other oxidatively induced DNA modifications in genomic DNA of Arabidopsis. These included 5-HmdC, 5-formyl-2′-deoxycytidine (5-FodC), 5-carboxyl-2′-deoxycytidine (5-CadC), 5-hydroxymethyl-2′-deoxyuridine (5-HmdU), and the (5′S) diastereomer of 8,5′-cyclo-2′-deoxyguanosine (S-cdG). We found that, in Arabidopsis DNA, the levels of 5-HmdC, 5-FodC, and 5-CadC are approximately 0.8 modifications per 106 nucleosides, with the frequency of 5-HmdC (per 5-mdC) being comparable to that of 5-HmdU (per thymidine). The relatively low levels of the 5-mdC oxidation products suggest that they arise likely from reactive oxygen species present in cells, which is in line with the lack of homologous Tet-family dioxygenase enzymes in Arabidopsis. 相似文献
110.
Temperature Gradient Measurements by Using Thermoelectric Effect in CNTs-Silicone Adhesive Composite
Muhammad Tariq Saeed Chani Kh. S. Karimov Abdullah M. Asiri Nisar Ahmed Muhammad Mehran Bashir Sher Bahadar Khan Malik Abdul Rub Naved Azum 《PloS one》2014,9(4)
This work presents the fabrication and investigation of thermoelectric cells based on composite of carbon nanotubes (CNT) and silicone adhesive. The composite contains CNT and silicon adhesive 1∶1 by weight. The current-voltage characteristics and dependences of voltage, current and Seebeck coefficient on the temperature gradient of cell were studied. It was observed that with increase in temperature gradient the open circuit voltage, short circuit current and the Seebeck coefficient of the cells increase. Approximately 7 times increase in temperature gradient increases the open circuit voltage and short circuit current up to 40 and 5 times, respectively. The simulation of experimental results is also carried out; the simulated results are well matched with experimental results. 相似文献