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11.
目的 采用HPLC法测定不同产地淫羊藿药材中7种主要黄酮类成分的含量。 方法 色谱柱为SHISEIDO MG-C18柱 (3.0 mm×100 mm, 3.0 μm);流动相为乙腈(A)和0.1%的甲酸水溶液(B),梯度洗脱,A相含量随时间的变化:25%(0~10 min),25%~40%(10~12 min),40%~45% (12~22 min), 45%~75% (22~25 min), 75%(25~30min);流速0.6 mL/min;检测波长270 nm;柱温25 ℃;进样量5 μL。淫羊藿药材以70%乙醇超声提取。 结果 7种黄酮类成分朝霍定A、朝霍定B、朝霍定C、淫羊藿苷、淫羊藿次苷I、淫羊藿次苷II、脱水淫羊藿素在30 min内基线分离。方法学验证表明,线性关系良好(r=0.9999),日内日间精密度RSD%均小于2.0%,回收率在98%~102%之间,稳定性和重复性RSD%也均小于2.0%,符合方法学要求。测定了对照药材及辽宁、甘肃、湖北3个产地淫羊藿中7种黄酮类成分的含量。 结论 该方法快速简便,可为淫羊藿药材的质量控制提供依据,也为进一步开展淫羊藿中黄酮类成分的药动学及组织分布研究奠定了良好的基础。  相似文献   
12.
目的:优化返魂草总黄酮的提取工艺。方法:以返魂草中总黄酮含量为考察指标,通过单因素实验考察超声时间、温度、功率等对返魂草有效成分含量的影响,采用正交设计实验法确定最佳提取工艺。结果:乙醇回流法提取最佳工艺为:提取时间150 min,溶剂70%乙醇,液料比22∶1。结论:乙醇回流法提取返魂草总黄酮操作方便,工艺稳定,重现性好,适于工业化生产。  相似文献   
13.
It has been shown that the extracts including eupatilin and quercetin-3-β-D-glucuronopyranoside had mucoprotective effects on the esophagus and stomach through their antioxidant activities. This study was designed to investigate the anti-inflammatory effect of these flavonoid compounds in an animal model of inflammatory bowel disease induced by 2,4,6-trinitrobenzene sulfonic acid. Experimental colitis was induced by intracolonic administration of 2,4,6-trinitrobenzene sulfonic acid. Extracts including eupatilin or quercetin-3-β-D-glucuronopyranoside were orally administered to animals 48, 24, and 1 h prior to the induction of colitis and then again 24 h later. The animals were sacrificed 48 h after by 2,4,6-trinitrobenzene sulfonic acid treatment and the macroscopic appearance of the colonic lesions was scored in a blinded manner on a scale of 1 to 10. The inflammatory response to colitis induction was assessed by measuring myeloperoxidase activity, nitric oxide production, tumor necrosis factor-α expression, total glutathione levels, and malondialdehyde concentrations in the colon. The results indicated that extracts including eupatilin and extracts including quercetin-3-β-D-glucuronopyranoside dose-dependently improved the morphology of the lesions induced by 2,4,6-trinitrobenzene sulfonic acid and reduced the ulcer index accordingly. In addition, rats receiving extracts including eupatilin and extracts including quercetin-3-β-D-glucuronopyranoside showed significantly decreased levels of mucosal myeloperoxidase activity, nitric oxide production, tumor necrosis factor-α expression, and malondialdehyde levels, and increased total glutathione levels. Extracts including eupatilin and extracts including quercetin-3-β-D-glucuronopyranoside ameliorated the inflammatory response and colonic injury in acute colitis by decreasing oxidative stress and neutrophil activation. Extracts including eupatilin and extracts including quercetin-3-β-D-glucuronopyranoside may inhibit acute colitis.  相似文献   
14.
The use of dietary or medicinal plant based natural compounds to disease treatment has become a unique trend in clinical research. Flavonoids, a group of polyphenolic compounds have drawn significant attention due to their modulatory effects on inflammasomes associated with the initiation and progression of chronic disorders including metabolic, neurodegenerative diseases and cancer. In this article, the role of most commonly studied natural flavonoids with their disease-specific impact via inflammasomes as a potential molecular target has been described. Since the role of inflammation is evident in multiple diseases, flavonoids may serve as a promising tool in drug discovery for the intervention of chronic diseases by manipulating the status of inflammation via inflammasome targeting.  相似文献   
15.
The aim of this study was to determine the influence of exogenous methyl jasmonate (MJ) on the content and composition of flavonoids (isoflavones) in extracts from hypocotyls (with cotyledons) and radicles of yellow lupine (Lupinus luteus L.) var. Polo and in extracts from radicles of narrow-leafed lupine (Lupinus angustifolius) var. Graf. Lupine seeds were harvested when fully ripe. Two months after harvest, the effect of various MJ concentrations (10−6 M to 10-3M) on seed viability, seed vigor and the content and composition of flavonoids in extracts from seedlings that emerged from germinated lupine seeds (72 h, 20 °C) was determined. At high concentrations (10-4 M to 10-3 M), MJ suppressed the germination rate and germination capacity of seeds and decreased the growth rate of seedlings of the analyzed varieties of yellow and narrow-leafed lupines in the first 5 days of growth. In seedlings, MJ significantly increased the content of isoflavones (including daidzin, genistin, daidzein, and genistein) in 3-day-old hypocotyls (with cotyledons) and radicles of yellow lupine. This correlation was also observed in the hypocotyls (with cotyledons) and radicles of 3-day-old narrow-leafed lupine seedlings treated with MJ. Narrow-leafed lupine seeds were more sensitive to exogenous MJ then yellow lupine seeds during germination.  相似文献   
16.
ObjectivesThe aim of this study was to evaluate the flavonoid content of an ethanolic leaf extract from the medicinal plant Rourea induta Planch. (RIEE) and to investigate its hepatoprotective potential and in vivo antioxidant effects.MethodsUsing samples from carbon tetrachloride-treated Wistar female rats treated orally with or without RIEE, we evaluated the aspartate aminotransferase, alanine aminotransferase, and total bilirubin levels in plasma; the levels of the hepatic oxidative stress markers catalase, superoxide dismutase, glutathione peroxidase, and reduced glutathione in liver homogenates; and the thiobarbituric acid reactive substance levels. A histopathology study was performed. A quantitative analysis of the RIEE extract was performed using high-performance liquid chromatography to evaluate its flavonoid content.ResultsOral administration of RIEE significantly reduced carbon tetrachloride-induced elevations in the levels of plasma markers of hepatic damage and lipid peroxidation. It also rescued histopathologic alterations observed in the liver and levels of oxidative stress markers.ConclusionsRIEE exhibits antioxidant and hepatoprotective activities in vivo, which may be attributable to its flavonoids composition [hyperin (2), quercetin-3-O-β-xyloside (4), quercetin-3-O-α-arabinofuranoside (5), and quercetin (6)].  相似文献   
17.
18.
ObjectiveTo evaluate wound healing potential of flavonoid fractions of Martynia annua (M. annua) Linn. leaves in diabetic rats on the basis of folkloric information and preliminary study.MethodsThe flavonoid compound luteolin and apigenin were isolated from dried leaves of plant by column chromatography. The two concentrations (0.2% and 0.5% w/w) of luteolin and flavonoid fraction were selected for topically applied as ointment on diabetic wound. The Povidone Iodine Ointment USP was used as a reference. On 18th days, protein content, hydroxyproline and antioxidants (SOD, CAT and GSH) level in granuloma tissues were determined.ResultsThe results showed that, percent wound contraction were observed significantly (P<0.01) greater in MAF fraction and 0.5% w/w of luteolin treatment groups. Presence of matured collagen fibres and fibroblasts with better angiogenesis were observed in histopathological studies.ConclusionsIn conclusion, our findings suggest that flavonoid fraction (MAF) and luteolin (0.5% w/w) may have potential benefit in enhancing wound healing in diabetic condition, possibly due to free-radical scavenging activity of plant.  相似文献   
19.
In this study, we explored the capacity of different tomato rootstocks to improve the nutritional value of tomatoes grown in a greenhouse during the winter–spring period under low temperature and light conditions. The results showed that relative to nongrafted plants, some grafted rootstocks either did not affect or had detrimental effects on the nutritional parameters measured. In addition, the amount of serotonin was significantly lower in tomatoes from all grafted rootstocks than in tomatoes from the nongrafted plants. Nevertheless, relative to the nongrafted plants, some grafted treatments increased total macroelements (by 1.16 times), total microelements (by 1.43 times), protein content (by 17%), free total and essential amino acids (by respectively 23% and 19%), total phenolic compounds (by 11%), vitamin C (by 13.8%), lycopene (by 48%), and also total hydrocinnamic acids (by 67%) and flavonoids (by 279%). As the grafted treatments did not increase the tomato yield, we hypothesize that these compounds accumulated in the tomatoes due to the lack of increased biomass, which prevented a dilution effect on the compounds of interest in the fruits.  相似文献   
20.
Several epidemiological, cellular, and molecular studies demonstrate the role of environmental chemicals with endocrine disrupting activities, typical of Westernized societies, in the pathogenesis of numerous diseases including cancer. Nonetheless this information, the design and execution of studies on endocrine disruptors are not yet cognizant that the specific actions of individual hormones often change with development and ageing, they may be different in males and females and may be mediated by different receptors isoforms expressed in different tissues or at different life stages. These statements are particularly true when assessing the hazard of endocrine disruptors against 17β-estradiol (E2) actions in that this hormone is crucial determinant of sex-related differences in anatomical, physiological, and behavioral traits which characterize male and female physiology. Moreover, E2 is also involved in carcinogenesis. The oncogenic effects of E2 have been investigated extensively in breast and ovarian cancers where hormone-receptor modulators are now an integral part of targeted treatment. Little is known about the E2 preventive signalling in colorectal cancer, although this disease is more common in men than women, the difference being more striking amongst pre-menopausal women and age-matched men. This review aims to dissect the role and action mechanisms of E2 in colorectal cancer evaluating the ability of estrogen disruptors (i.e., xenoestrogens) in impair these E2 actions. Data discussed here lead to define the possible role of xenoestrogens in the impairment and/or activation of E2 signals important for colorectal cancer prevention.  相似文献   
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