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71.
This study was aimed to investigate the anticancer potential of Euphorbia milii (E. milii) using an exquisite combination of phytopharmacological and advanced computational techniques. The chloroform fraction (Em-C) of E. milii methanol extract showed the highest antioxidant activity (IC50: 6.41 ± 0.99 µg/ml) among all studied fractions. Likewise, Em-C also showed significant cytotoxicity (IC50: 11.2 ± 0.8 µg/ml) when compared with that of standard compound 5-fluorouracil (5-FU) (IC50: 4.22 ± 0.6 µg/ml) against hepatocarcinoma cell line (HepG2). However, in a human cervical cancer cell line (HeLa), Em-C demonstrated a non-significant difference in cytotoxicity (22.1 ± 0.8 µg/ml) when compared with that of 5-FU (IC50: 6.87 ± 0.5 µg/ml). Furthermore, Western blot and qRT-PCR analysis revealed that the suppression of HepG2 cells was the consequence of a tremendous decrease in CDK2 and E2F1 protein expression. The GC–MS analysis of Em-C revealed the unique presence of cyclobarbital (CBT) and benzodioxole derivative (BAN) as major constituents. Furthermore, molecular docking of compounds BAN, CBT, and MBT into the binding site of different molecular targets i.e. cyclin dependent kinase 2 (CDK2), thymidylate synthase (TS), caspase 3, BCL2 and topoisomerase II was carried out. Compounds BAN and CBT have demonstrated remarkable binding affinity towards CDK2 and thymidylate synthase, respectively. Molecular dynamic simulation studies have further confirmed the finding of docking analysis, suggesting that CDK2 and TS can act as an attractive molecular target for BAN and CBT, respectively. It can be concluded that these E. milii phytoconstituents (BAN and CBT) may likely be responsible for anti-invasive activity against HepG2 cells.  相似文献   
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BackgroundMetals can disturb the integrity of physiological and biochemical mechanisms in fish. Thus components of defense as an antioxidant system are significant biomarkers due to their vital role in coping with metal stress. The aim of the current study is to investigate the direct effects of Cd, Cu, and Zn sublethal exposures (in vitro) on the antioxidant system parameters in the liver and kidney of Nile tilapia.MethodsThe antioxidant enzyme activities and GSH levels were analyzed after in vitro sublethal metal (200 and 400 μg/L Cd, Cu, and Zn) treatments of Oreochromis niloticus liver and kidney supernatants.ResultsMetals even at lower levels caused significant changes in the levels of antioxidant system parameters due to concentration, metal, and tissue type. GSH metabolism parameters were more responsive to the metal effect. TBARS levels and GPX activity were mostly increased while CAT, SOD, rGSH, and GSH/GSSG levels decreased. The kidney was more affected than the liver in vitro conditions. Cu was more effective in the liver whereas it was Zn for the kidney. Cd caused negative correlations among the antioxidant enzymes. Significant correlations were found between enzymes and GSH levels upon Zn and Cu exposures.ConclusionsDirect metal effects may trigger different response trends due to their nature and tissue differences. The current data provide a knowledge about which antioxidant biomarkers can define better the oxidative stress caused by direct metal effect for further studies including in vivo experiments.  相似文献   
74.
Clinical decision is often difficult with chlorhexidine mouthwash. The use of antioxidant mouthwashes for the treatment of periodontal disease is in practise. Therefore, it is of interest to collect gleaned information on Antioxidant mouthwashes as periodontal therapy from known literature. Improvement in treatment using antioxidant mouthwashes is reported in several studies. The mouthwash with antioxidants has similar anti-gingivitis, antiplaque and antimicrobial effects as that of chlorhexidine mouthwash.  相似文献   
75.
BackgroundHyperglycemia and hyper oxidative stress are indicators of diabetes mellitus which is also accompanied with decreased levels of antioxidant enzymes. While oxidative stress is important in increasing insulin secretion and controlling blood sugar level at the same time excess oxidative stress leads to the destruction of beta cells of pancreas resulting in to low insulin production and hyperglycemia. A balance between the levels of oxidative radicals and insulin production is needed, but is not defined yet. Hyperglycemia also leads to hyperlipidemia which can contribute to various health conditions like cardiovascular diseases.ObjectivesThis study was designed to study the oxidative stress and lipid levels in diabetic rats. This also was designed to elucidate the effect of Dhanwantaram Kashayam, an Ayurvedic polyphenolic derived from plants on lipid metabolism and oxidative radical scavenging in diabetic rats.MethodsRats were made diabetic by injecting streptozotocin. Different enzymes involved in oxidative radical scavenging and lipid profiles including triglycerides, total cholesterol, free fatty acids and phospholipids were estimated using standard methods reported elsewhere.ResultsLevel of antioxidant enzymes were lower in diabetic rats compared to normal controls. Administration of Dhanwantaram Kashayam restored the enzyme activity as well as reduced levels of different lipids in diabetic rats.ConclusionsAdministration of Dhanwantaram Kashayam increased the activity levels of antioxidant enzymes and reduced the levels of total cholesterol, phospholipids and triglycerides. The results of this study point to the possibility of developing Dhanwantaram Kashayam as a dietary supplement which can alleviate the complications associated with diabetes or prevent them altogether.  相似文献   
76.
Background and aimOxidative stress and inflammation are conditions that are deeply involved in atherosclerosis and consequent coronary artery disease (CAD). Therefore, the aim of this study was to assess the relationship among circulating antioxidant vitamins (C, A, E), copper, and other pro- or antioxidant/inflammation markers in patients with and without CAD under preventive medication.Subjects and methods174 Azorean subjects symptomatic for CAD (age 56 ± 9y; 68 % men) submitted to coronary angiography were split into 2 groups: one formed by CAD patients (≥50 % stenosis in at least one major coronary vessel) and the other by non-CAD patients (<50 % stenosis). Both groups were age-, sex- and BMI-matched. Plasma levels of vitamins or copper were measured by HPLC and AAS, respectively.Results and conclusionsLower vitamin C levels were observed in CAD patients (mainly in women, who exhibited a high rate of diabetes mellitus) as compared to the non-CAD ones. Also, CAD patients (mainly men) exhibited significantly higher concentrations of plasma copper than their non-CAD counterparts (1.17 ± 0.3 mg/L vs. 1.09 ± 0.3 mg/L, p = 0.030). In bivariate analysis, plasma copper levels were positively associated with serum LDL-cholesterol (r=0.22; p = 0.004) and chiefly with C-reactive protein (r=0.40; p < 0.001). Furthermore, they were significantly lower in recurrent vs. non recurrent CAD patients (1.07±0.2 vs. 1.24±0.3 mg/L, p = 0.004). ROC analysis showed that plasma copper, whenever >1.06 mg/L, was an independent risk factor for CAD in primary prevention for men, which suggests that its levels can fluctuate with medical therapy (such as anti-inflammatory), thus indicating that copper is not a reliable marker for CAD. Moreover, plasma copper concentration was not associated with CAD severity. Yet, results do suggest that, even within its reference concentration range, it could be useful as an acute inflammation marker in CAD management.  相似文献   
77.
The yield and quality of leafy vegetables can be compromised by reduced water availability. Glutamic acid is involved in different biological processes and among them it plays an important role in chlorophyll and proline biosynthesis. The aim of this work was to evaluate the possible efficacy of glutamic acid in counteracting water stress in romaine lettuce. Lettuce plants were grown in pots filled with substrate and subjected to water deprivation. A glutamic acid solution (1.9 mM) was applied as foliar treatment, both in stressed and non-stressed plants. The effect of the treatment was evaluated at different time points during the experiment in order to evaluate changes at a molecular, physiological, biochemical and agronomic level. Yield was reduced by 35% in stressed plants, while no significant changes in quality parameters were observed, except for nitrate content, which increased under water stress. At a molecular level, the expression of genes encoding for ROS scavenging enzymes was monitored but, apparently, glutamic acid did not significantly prevent the water stress response. Slightly positive effects deriving from glutamic acid application were found for nitrate and proline contents, suggesting that a possible mode of action of glutamic acid would involve a role for these molecules. Further studies are required, also on other crop species, for confirming these results. Different concentrations and application modes should be also tested.  相似文献   
78.
Valeriana jatamansi Jones, an important medicinal herb of the Himalayan region, is an essential source of many therapeutic compounds and is traded/consumed in very high volume. The hypothesis of this study was that different seasons and light conditions may affect the content of medicinally valuable components with changes in the morpho-physiological attributes of the plant. Growing plants under suitable light conditions and harvesting of appropriate plant parts in optimum season is crucial for harnessing the full potential of the crop. Thus, the study was carried out to determine the seasonal response of V. jatamansi plants (genetically identical plants of same age) in terms of growth and phytochemical content under two different light conditions (full sunlight and 50% shade). During all seasons, growth parameters (plant height, leaf number, leaf area, relative water content, plant biomass) and the principle bioactive compounds (valerenic acid) were higher under shade conditions, while total flavonoids, tannins, phenolic compounds and antioxidant activities were higher under full sunlight conditions. HPLC analysis revealed that valerenic acid and most of the phenolic content were higher during summer season, especially in leaf part of the plant. The study suggested harvesting of V. jatamansi plants (especially leaf), during summer season to harness high quality raw material and to prevent loss of belowground parts. This strategy can be adopted by farmers for large scale cultivation of species.Supplementary InformationThe online version of this article contains supplementary material available at 10.1007/s12298-021-00944-0  相似文献   
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连作障碍严重限制了当归产业的可持续发展。为了探索当归(Angelica sinensis)高效栽培技术,本研究在当归主产区甘肃省渭源县设置5种种植模式(A: 豌豆-当归-当归,对照;B: 豌豆-小麦-当归;C: 豌豆-蒙古黄芪-当归;D: 豌豆-马铃薯-当归;E: 豌豆-休耕-当归),于采挖期分别测定不同种植模式下,当归根际土壤理化特性和细菌基因组DNA相对丰度,分析不同种植模式对当归根际土壤理化特性、细菌群落多样性和代谢通路的影响。结果表明: 1) 5种种植模式下当归根际土壤理化特性差异较大。与对照相比,C模式根际土壤的电导率显著增加,B、D和E模式的电导率略有下降,B、C、D和E模式的土壤CO2呼吸速率显著提高。2) 5种种植模式的当归根际土壤细菌隶属于26门368属,其中,芽单胞菌门的芽单胞菌属、变形菌门的鞘脂单胞菌属和酸杆菌门的Subgroup_6属为优势菌属。与对照相比,B、C模式变形菌门和放线菌门的相对丰度显著增加,D模式酸杆菌门的相对丰度显著降低;E模式变形菌门、酸杆菌门和放线菌门的相对丰度显著增加。3) 5种种植模式下,当归根际土壤的pH值、电导率、有机质、碱解氮、有效磷和速效钾含量与变形菌门细菌的相对丰度呈显著负相关。4) 5种种植模式下,当归根际土壤中6种代谢通路细菌的相对丰度差异显著。C模式对当归根际土壤理化特性和细菌群落有较好的调节作用,是克服当归连作障碍的主要种植模式。  相似文献   
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