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1.
Bark extract of Pinus pinaster has a long history of ethnomedicinal use and is available commercially as herbal dietary supplement with proprietary name pycnogenol. It is used as a food supplement to overcome many degenerative disorders. Rohdewald (2002) wrote the first comprehensive review of extract highlighting its antioxidative nature and its role in different diseases. Later, Watson (2003) and Gulati (2005) in their reviews about cardiovascular health, described the extract as a best neutraceutical agent in this regard. The objective of this paper is to review the current research on this extract in terms of extraction methods, its pharmacological, toxicological and nutraceutical effects and clinical studies. Web sites of Google Scholar, Pubmed and Medline were searched for articles written in English and published in peer-reviewed journals from 2006 to 2009 and sixty-nine research articles were extracted. Of these, two are about extraction advancement and analysis while the rest relate to its clinical, biological and nutraceutical aspects.  相似文献
2.
Significant oral antipyretic activity in rabbits was exhibited by hexane-, chloroform- and water-soluble extracts of Artemisia absinthium, Viola odorata, Melia azadirachta and Fumaria parviflora comparable in potency aspirin. Pyresis was induced by subcutaneous yeast injections. Antipyretic activity was more prominent in the hexane-soluble portions of these plants. Insignificant to no antipyretic effects were produced by extracts of Butea frondosa, Berberis lycium and Sisymbrium irio. No obvious toxic effects were noted for any of the plant extracts up to doses of 1.6 g/kg.  相似文献
3.
A new withanolide glycoside, 17beta-hydroxy-14, 20-epoxy-1-oxo-[22R]-3beta-[O-beta-D-glucopyranosyl]-witha-5, 24-dienolide (1), has been isolated from the whole plant of Physalis peruviana. Its identity was determined using a combination of spectroscopic data including 2D NMR techniques and chemical transformations.  相似文献
4.
Rapid decline of plant resources due to their conventional use needs ex-situ and in-situ conservation, training of the community regarding collection of medicinal plants and their marketing. In this regard, the Bulashbar valley, Astore, District Diamer was identified as a case study. The main objectives of this activity were to enlist economic, medicinal and aromatic plants including their occurrence, general distribution and abundance in the project areas; to determine traditional use and pharmaceutical values of each medicinal plant species found in the project area. Ethnobotanical studies of the area revealed that 33 plants were being used by the local communities for medicinal purposes. Two species, Bunium persicum and Ephedra gerardiana, are recommended for in vitro cultivation to obtain quick benefits. While Hippophae rhamnoides can be sustainably used for socio-economic uplift of the local communities.  相似文献
5.
In this report we investigated the effects of the aqueous fraction (AF) isolated from Delphinium denudatum on sustained repetitive firing in cultured neonatal rat hippocampal pyramidal neurons. Blockade of SRF is one of the basic mechanisms of antiepileptic drugs (AED) at the cellular level.

The effects of aqueous fraction (0.2–0.6 mg/ml) were compared with the prototype antiepileptic drug, phenytoin (PHT). Using the whole cell current-clamp technique, sustained repetitive firing was elicited in neurons by a depolarizing pulse of 500 ms duration, 0.3 Hz and 0.1–0.6 nA current strength. Similar to phenytoin, aqueous fraction reduced the number of action potentials (AP) per pulse in a concentration-dependent manner until no action potentials were elicited for the remainder of the pulse. There was a corresponding use-dependent reduction in amplitude and Vmax (velocity of upstroke) of action potentials. The Vmax and amplitude of the first action potential was not affected by phenytoin, while aqueous fraction exhibited concentration-dependent reduction. At 0.6 mg/ml aqueous fraction reduced Vmax to 58–63% and amplitude to 16–20% of the control values. The blockade of sustained repetitive firing by aqueous fraction was reversed with hyperpolarization of membrane potential (−65 to −75 mV) while depolarization of membrane potential (−53 to −48 mV) potentiated the block.

The results suggest that aqueous fraction blocks sustained repetitive firing in hippocampal neurons in a use-dependent and voltage-dependent manner similar to phenytoin. However, unlike phenytoin, which interacts preferably with the inactive state of the Na+ channel, the compounds present in aqueous fraction apparently also interact with the resting state of the Na+ channels as suggested by dose-dependent reduction of Vmax and amplitude of first AP. We conclude that aqueous fraction contains potent anticonvulsant compounds.  相似文献

6.
Crude extract of Valeriana wallichii rhizome (Vw.Cr) and its fractions were studied for possible antispasmodic and blood pressure lowering activities to rationalize some of the folkloric uses. In rabbit jejunum preparations, Vw.Cr (0.1–3.0 mg/mL) caused relaxation of spontaneous contractions. When tested against high K+ (80 mM)-induced contractions it produced weak inhibitory effect, while caused complete relaxation of the contractions induced by low K+ (20 mM). In the presence of glibenclamide (3 μM), the inhibitory effect of low K+ was shifted to the right, similar to that produced by cromakalim while, verapamil caused no differentiation in its inhibitory effect against low and high K+-induced contractions. In guinea pig ileum, the plant extract produced similar results as in rabbit jejunum. Intravenous administration of Vw.Cr, produced fall in arterial blood pressure in normotensive anaesthetized rats and this effect was partially blocked by glibenclamide. In rabbit aortic preparations, plant extract also caused a selective and glibenclamide-sensitive relaxation of low K+ (20 mM)-induced contractions. Activity-directed fractionation studies revealed that the observed activity was distributed both in the chloroform and aqueous fractions. These results indicate that the antispasmodic and hypotensive effects of Valeriana wallichii are mediated possibly through KATP channel activation, which justify its use in gastrointestinal and cardiovascular disorders.  相似文献
7.
The most common drinking beverage in large portion of the world is Camellia sinensis (green tea). In the present study, we evaluated the adjuvant effect of green tea and tea polyphenols to particulate and non‐particulate antigens. BALB/c mice were immunized with particulate and non‐particulate antigens. Modulation of immunoglobulin‐secreting splenocytes, IgG‐mediated and IgM‐mediated immunity, was evaluated by hemolytic plaque assay and enzyme‐linked immunosorbent assay, respectively. Dose‐dependent response of tea polyphenols was also assayed. Phenolic content was measured in crude preparations of green tea. We observed a stimulatory effect of green tea preparations on humoral immune response mediated by the increased number of antibody‐secreted cells in spleen. A significant increase in IgM‐mediated and IgG‐mediated immune response to non‐particulate antigen was also observed in green tea‐treated animals. A dose‐dependent adjuvant effect was seen in the case of tea polyphenols for a longer period of time compared with crude tea preparations. This study indicates polyphenols as major constituents responsible for the enhanced and sustained adjuvant activity of green tea. We suggest that tea polyphenols might be considered for real‐life evaluation during adjuvant‐mediated vaccination trial programs. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献
8.
Traditional medicinal plants are often used for both the prevention and the treatment of local diseases. Taking into consideration the medicinal importance of Hedera nepalensis within local Pakistani traditions, the present study was undertaken to analyze the in vitro cancer chemopreventive and cytotoxic properties of the plant. The in vitro cancer chemopreventive testing was performed using nitrite assay, NFκB assay, aromatase assay, and quinone reductase 1 (QR1) assay. The cytotoxic potential was evaluated on three cancer‐cell lines: MCF‐7, MDA‐MB‐231, and HeLa using sulforhodamine B (SRB) assay. The results of cancer chemopreventive assays show that n‐hexane and ethyl acetate fractions of tested plant have promising cancer chemopreventive potential. Lupeol isolated from n‐hexane as well as ethyl acetate fraction showed lowest IC50 (0.20 ± 1.9 μM) in NFκB assay. Crude extract and its fractions inhibited the growth of three cancer cell lines by more than 60%, IC50 value of lupeol varied from 2.32 to 10.2 μM. HPLC‐DAD‐based quantification of lupeol in different plant tissues demonstrated that leaves of H. nepalensis are a rich source of lupeol (0.196 mg/100 mg dry weight). Our data have shown that H. nepalensis harbors cancer chemopreventive and cytotoxic agents. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献
9.
The crude ethanolic extract of Chrozophora prostrata (Cp.Cr) was tested using in vivo and ex vivo assays for its possible bronchodilatory effects in order to validate its medicinal use in respiratory disorders, like asthma and cough. Cp.Cr exhibited dose‐dependent inhibition of carbachol (CCh)‐induced bronchospasm in anesthetized rats, similar to aminophylline. When tested on guinea‐pig tracheal preparations, Cp.Cr caused relaxation of both CCh (1 μM) and high K+ (80 mM)‐induced contractions with comparable potencies, similar to papaverine, a dual inhibitor of phosphodiesterse (PDE) and Ca+2 influx. Pre‐treatment of the tracheal tissues with Cp.Cr resulted in potentiation of the inhibitory effect of isoprenaline on CCh‐induced contractions, like that caused by papaverine indicative of PDE inhibitory activity, which was confirmed when Cp.Cr concentration dependently (1 and 3 mg/mL) increased intracellular cAMP levels of the tracheal preparations, like papaverine. Cp.Cr shifted concentrationresponse curves of Ca+2 constructed in guinea‐pig tracheal preparation towards right with suppression of the maximum response, similar to both verapamil and papaverine. These data indicate bronchodilator activity of Chrozophora prostrata mediated possibly through dual inhibition of PDE and Ca+2 influx, thus, showing therapeutic potential in asthma with effect enhancing and side‐effect neutralizing potential Copyright © 2016 John Wiley & Sons, Ltd.  相似文献
10.
Morus nigra Linn. (black mulberry) is used in gastrointestinal ailments. This study demonstrates gut modulatory properties of M. nigra. The prokinetic, laxative, and antidiarrheal activities of M. nigra were assessed in mice, while isolated rabbit jejunum and guinea‐pig ileum were used to explore insight into mechanism(s). At 30 and 70 mg/kg, the crude extract of M. nigra (Mn.Cr) exhibited atropine‐sensitive prokinetic and laxative effects, similar to carbachol (CCh). While at higher doses (100, 300, and 500 mg/kg), Mn.Cr offered protection against castor oil‐induced diarrhea. In rabbit jejunum, Mn.Cr and its chloroform fraction inhibited CCh‐induced contractions more potently compared with high K+ (80 mm ). Conversely, petroleum fraction was more potent against high‐K+‐induced contractions. At 0.01 mg/mL, Mn.Cr caused a parallel shift in acetylcholine concentration–response curves (CRCs) followed by a non‐parallel shift at 0.03 mg/mL, similar to dicyclomine. At further tested concentrations, Mn.Cr (0.1 and 0.3 mg/mL) and petroleum fraction suppressed Ca2+ CRCs, similar to verapamil. In guinea‐pig ileum, Mn.Cr, its aqueous and ethyl acetate fractions exhibited atropine‐sensitive gut stimulant activity along with additional uncharacterized excitatory response in the aqueous fraction only. These results suggest that black mulberry possesses prokinetic, laxative, and antidiarrheal effects, putatively mediated through cholinomimetic, antimuscarinic, and Ca2+ antagonist mechanisms, respectively. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献
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