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691.

The changes in lipid peroxidation, H2O2, proline, protein, involvement of different antioxidant systems (catalase, guaiacol peroxidase, ascorbate peroxidase) and callus-related traits were investigated under salt stress in the callus of two different ploidy levels of Brassica including B. juncea and B. oleracea. The calluses of B. juncea genotypes were less sensitive to NaCl stress in comparison with those of B. oleracea while increasing the concentrations of NaCl from 0 to 200 mM. Tetraploid genotype (B. juncea cr3356) showed a significant increase in the contents of protein and proline, and guaiacol peroxidase activity and catalase enzymes at higher salinity levels. In addition, a significant decrease occurred in the amount of H2O2 and malondialdehyde along with increasing the salinity intensity. Diploid cultivar (B. oleracea bra 2828) had the lowest enzymatic activities and the highest content of H2O2 and malondialdehyde along with an increase in the salinity level. Therefore, this genotype was identified as the most sensitive cultivar under the salinity stress. The salinity resistance difference between diploid and amphidiploid species could be attributed to the differences in the ploidy level of these species. This result underlines the fact that the tetraploid genome of B. oleracea could be considered as a suitable candidate for production under salinity conditions through maintaining higher activities of antioxidant enzymes.

  相似文献   
692.
Molecular Biology Reports - Preeclampsia (PE) is a major complication of pregnancy and remains a leading cause of neonatal and maternal mortality worldwide. Several studies have revealed that the...  相似文献   
693.
Molecular Biology Reports - Joubert syndrome (JS) is a rare inherited neurodevelopmental condition characterized by hypotonia, ataxia, developmental delay, abnormal eye movements, neonatal...  相似文献   
694.
695.
Reperfusion injury is one of the main reasons of cardiac disease morbidity. Phytopharmaceuticals are gaining importance in modern medicine of cardioprotection because of their multiplex capacity. The aim of this study was to investigate the effect of diosgenin on the inflammatory response induced by myocardial ischemia and reperfusion injury and the role of mitochondrial ATP-sensitive potassium (mitoKATP) channels in this regard. Wistar rats (250–300 g) were used in this study. The Langendorff-perfused hearts of animals were subjected to a 30-min global ischemia followed by a 90-min reperfusion. The lactate dehydrogenase (LDH) release was measured by spectrophotometry. The levels of inflammatory mediators tumor necrosis factor-alpha (TNF-α), interleukin-1beta (IL-1β), and IL-6 in the supernatant of heart’s left ventricle were measured using an enzyme-linked immunosorbent assay rat specific ELISA kit. The LDH release into the coronary effluent during reperfusion was significantly decreased, and cardiac contractility significantly improved by diosgenin preadministration as compared with those of control or Cremophor-EL (solvent of diosgenin) groups (398?±?48 vs. 665?±?65 or 650?±?73 ml/min) (P?<?0.01). Administration of diosgenin before the main ischemia significantly reduced the levels of IL-6 (P?<?0.05), IL-1β, and TNF-α (P?<?0.01) in the reperfusion phase of diosgenin-treated hearts as compared with untreated control hearts. Inhibition of mitoKATP channels by 5-hydroxydecanoate significantly reverses the cardioprotective effects of diosgenin (P?<?0.05). The findings of the present study indicate that preconditioning with diosgenin may induce cardioprotective effect against reperfusion injury through reducing the production of inflammatory mediators and activating the mitoKATP channels.  相似文献   
696.
Biohydrogen production through water–gas shift (WGS) reaction by a biocatalyst was conducted in batch fermentation. The isolated photosynthetic bacterium Rhodopseudomonas palustris PT was able to utilize carbon monoxide and simultaneously produce hydrogen. Light exposure was provided as an indispensable requirement for the first stage of bacterial growth, but throughout the hydrogen production stage, the energy requirement was met through the WGS reaction. At ambient pressure and temperature, the effect of various sodium acetate concentrations in presence of CO-rich syngas on cell growth, carbon monoxide consumption, and biohydrogen production was also investigated. Maximal efficiency of hydrogen production in response to carbon monoxide consumption was recorded at 86 % and the highest concentration of hydrogen at 33.5 mmol/l was achieved with sodium acetate concentration of 1.5 g/l. The obtained results proved that the local isolate; R. palustris PT, was able to utilize CO-rich syngas and generate biohydrogen via WGS reaction.  相似文献   
697.

Purpose

Recently, using a long-run refinery simulation model, Bredeson et al. conclude that the light transportation fuels have roughly the same CO2 footprint. And, any allocation scheme which shows substantial difference between gasoline and diesel CO2 intensities must be seen with caution. The purpose of this paper is to highlight the inappropriate modeling assumptions which lead to these inapplicable conclusions into the current oil refining context.

Methods

From an economic point of view, optimization models are more suitable than simulation tools for providing decision policies. Therefore, we used a calibrated refinery linear programming model to evaluate the impact of varying the gasoline-to-diesel production ratio on the refinery's CO2 emissions and the marginal CO2 intensity of the automotive fuels.

Results and discussion

Contrary to Bredeson et al.'s conclusions, our results reveal that, within a calibrated optimization framework, total and per-product CO2 emissions could be affected by the gasoline-to-diesel production ratio. More precisely, in a gasoline-oriented market, the marginal CO2 footprint of gasoline is significantly higher than diesel, while the opposite result is observed within a diesel-oriented market. These two scenarios could reflect to some extent the American and the European oil refining industry for which policy makers should adopt a different per-product taxation policy.

Conclusions

Any relevant and economic ground CO2 policies for automotive fuels should be sensitive to the environmental consequences associated with their marginal productions. This is especially true in disequilibrium markets where the average and marginal reactions could significantly differ. Optimization models, whose optimal solution is fully driven by marginal signals, show that the refinery's global and/or per-product CO2 emissions could be affected by the gasoline-to-diesel production ratio.  相似文献   
698.
Intrinsic rates of population increase (r) were evaluated as a measure of population dynamics of four strains of Brachionus plicatilis and two strains of B. urceolaris from Iran in response to different salinities and feeding algae. Each rotifer strain was cultured at four salinities: 5, 20, 25 and 30‰ and fed with two microalgal species: Chlorella vulgaris and Nannochloropsis oculata. Salinity of 5‰ was critical for all the examined strains, at which r was at minimum and was different from the other salinities (P < 0.05). For B. plicatilis strains, the maximum r was observed in those fed on Chlorella at salinities of 10 and 30‰ (64 ± 0.01 day−1). While, in B. urceolaris, maximum r was for Nannochloropsis fed rotifers at salinity of 20‰ (0.69 ± 0.01 day−1). Maximum final population density (FD) was obtained for a strain of B. urceolaris fed on Nannochloropsis at 20‰ (329.3 ± 10.9 ind.mL−1). FD was relatively lower in B. plicatilis strains among all examined salinities. ANOVA showed the significant effect of salinity and rotifer strain, and algae × rotifer strain on both r and FD, and salinity × rotifer × algae on FD (P < 0.05). (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
699.
Multiple sclerosis is considered a prototype inflammatory autoimmune disorder of the CNS. Experimental autoimmune encephalomyelitis (EAE) induced by myelin oligodendrocyte glycoprotein is one of the best‐characterized animal models of multiple sclerosis. Comprehensive understanding of gene expression in EAE can help identify genes that are important in drug response and pathogenesis. We applied a 2‐DE‐based proteomics approach to analyze the protein expression pattern of the brain in healthy and EAE samples. Of more than 1000 protein spots we analyzed, 70 showed reproducible and significant changes in EAE compared to controls. Of these, 42 protein spots could be identified using MALDI TOF‐TOF‐MS. They included mitochondrial and structural proteins as well as proteins involved in ionic and neurotransmitter release, blood barriers, apoptosis, and signal transduction. The possible role of these proteins in the responses of mice to animal models of multiple sclerosis is discussed.  相似文献   
700.
The spatial heterogeneity of stomatal closure in response to rapid desiccation of excised well-watered Tradescantia virginiana leaves grown at moderate (55%) or high (90%) relative air humidity (RH) was studied using a chlorophyll fluorescence imaging system under non-photorespiratory conditions. Following rapid desiccation, excised leaves grown at high RH had both a greater heterogeneity and a higher average value of PSII efficiency (Phi(PSII)) compared with leaves grown at moderate RH. Larger decreases in relative water content resulted in smaller decreases in water potential and Phi(PSII) of high RH-grown leaves compared with moderate RH-grown leaves. Moreover, the Phi(PSII) of excised high RH-grown leaves decreased less with decreasing water potential, implying that the stomata of high RH-grown leaves are less sensitive to decreases in leaf water potential compared with moderate RH-grown leaves. After desiccation, some non-closing stomata were distributed around the main vein in high RH-grown leaves. Direct measurements of stomatal aperture showed 77% stomatal closure in the margins after 2 h desiccation compared with 40% closure of stomata in the main-vein areas in high RH-grown leaves. Faster closure of stomata in leaf margins compared with main-vein areas of leaves grown at high RH was related to substantially lower relative water content in these areas of the leaves.  相似文献   
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