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81.
82.

Ethnopharmacological relevance

Boesenbergia rotunda (L) Mansf. has been used for the treatment of gastrointestinal disorders including peptic ulcer. In the current study we aimed to investiagte the anti-ulcer activities of methanolic extract of B. rotunda (MEBR) and its main active compound, pinostrobin on ethanol-induced ulcer in rats. The possible involevement of lipid peroxidation, nitric oxide, cyclooxygenases and free radical scavenging mechanisms also has been investigated.

Materials and methods

Pinostrobin was isolated form the rhizomes of B. rotunda. Ulcer index, gastric juice acidity, mucus content, gross and histological gastric lesions and thiobarbituric acid reactive substances (TBARS) were evaluated in ethanol-induced ulcer in vivo. The effect of pinostrobin into lipopolysaccharide/interferon-γ stimulated rodent cells, COX-1 and COX-2 activities were done in vitro.

Results

Pre-treatment with MEBR, pinostrobin or omeprazole protected the gastric mucosa as seen by reduction in ulcer area and mucosal content, reduced or absence of submucosal edema and leucocytes infiltration. Pinostrobin significantly (p<0.05) lowered the elevated TBARS level into gasteric homogenate. Pinostrobin did not produced significant in vitro inhibition of NO from LPS/IFN-γ activated rodent cells without affecting the viability of these cells. Further, the compound did bot revleaed inhibitory effects on both COX- 1& 2 enzymes. The antioxidant assays also exhibited non significance in vitro.

Conclusion

Thus it can be concluded that MEBR possesses anti-ulcer activity, which could be attributed to indirect anti-oxidant mechanism of pinostrobin but not to the intervention with nitric oxide and COX inflammation pathways.  相似文献   
83.

Ethnopharmacological relevance

Phyllanthus amarus Schum. &; Thonn. belongs to the family Euphorbiaceae is a small herb well known for its medicinal properties and widely used worldwide. P. amarus is an important plant of Indian Ayurvedic system of medicine which is used in the problems of stomach, genitourinary system, liver, kidney and spleen. It is bitter, astringent, stomachic, diuretic, febrifuge and antiseptic. The whole plant is used in gonorrhea, menorrhagia and other genital affections. It is useful in gastropathy, diarrhoea, dysentery, intermittent fevers, ophthalmopathy, scabies, ulcers and wounds.

Materials and methods

The present review covers a literature across from 1980 to 2011. Some information collected from traditional Ayurvedic texts and published literature on ethanomedicinal uses of Phyllanthus amarus in different countries worldwide.

Results

Phytochemical studies have shown the presence of many valuable compounds such as lignans, flavonoids, hydrolysable tannins (ellagitannins), polyphenols, triterpenes, sterols and alkaloids. The extracts and the compounds isolated from P. amarus show a wide spectrum of pharmacological activities including antiviral, antibacterial, antiplasmodial, anti-inflammatory, antimalarial, antimicrobial, anticancer, antidiabetic, hypolipidemic, antioxidant, hepatoprotective nephroprotective and diurectic properties.

Conclusion

The present review summarizes information concerning the morphology, ecology, ethnopharmacology, phytochemistry, biological activities, clinical applications and toxicological reports of P. amarus. This review aims at gathering the research work undertaken till date on this plant in order to provide sufficient baseline information for future works and commercial exploitation.  相似文献   
84.
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   
85.
Oats are a rich source of β-glucans and bioactive phytochemicals. The established health-beneficial properties of oats have led to an increase in the consumption of oats and oat-based food products in recent years. The objective of the present study was to analyse and compare the polyphenol content and total antioxidant capacity (via FRAP (ferric ion reducing antioxidant power) and DPPH (2,2-diphenyl-1-picrylhydrazyl) inhibition) of 30 commercially available oat-based breakfast cereals. All of the breakfast cereals analysed were a significant source of polyphenols (1506–1853 μg gallic acid equivalents (GAE)/g) and antioxidants (1682–3542 μmol/l FRAP; 30–201% inhibition of DPPH compared to gallic acid standard). There was little difference between premium and budget brand varieties of the breakfast cereals. The polyphenol levels in an average serving (40 g) of an oat-based breakfast cereal are comparable to those found in fruits and vegetables. Overall, our findings suggest that consumption of oat-based breakfast cereals could be a significant contributor to the total polyphenol content and antioxidant potential of the diet.  相似文献   
86.
Picrorhizakurroa Royle ex Benth., a well-known traditional herb from the Scrophulariaceae family has a remarkable reputation among the indigenous medical practitioners. The antioxidant and anti-neoplastic activities of methanolic and aqueous extracts of P. kurroa rhizome were investigated in the present study. The total phenolic content was determined by a spectrophotometric method. The antioxidant efficacies of the extracts were studied employing radical scavenging assays (DPPH and OH), ferric reducing antioxidant property (FRAP) and thiobarbituric acid (TBA) assay for testing inhibition of lipid peroxidation. Furthermore, the cytotoxicity of the extracts was tested by XTT assay in MDA-MB-435S (human breast carcinoma), Hep3B (human hepatocellular carcinoma) and PC-3 (human prostate cancer) cell lines. The ability of the extracts to induce apoptosis was also investigated. Both extracts exhibited promising antioxidant potentials. The extracts were also observed to be cytotoxic at the tested dosage and were able to target cells towards apoptosis. The study concludes that P. kurroa possess diverse therapeutic potentials which might be useful in development of drugs or their precursors.  相似文献   
87.
It has been proved that oxidative stress increases when leukemia is accompanied by depression. This fact may indicate the role of oxidative stress in the development of depression in cancer patients. The aim of this study was to determine whether the acute myeloid leukemia of Brown Norway rats, which is accompanied by oxidative stress, evoked behavioral and receptor changes resembling alterations characteristic of rat models of depression. The rats were divided into two groups: leukemic rats and healthy control. Leukemia was induced through intraperitoneal injection of 107 promyelocytic leukemia cells to the Brown Norway rats. Depression-like behavior was evaluated in the forced swim test at 30 or 34 days after leukemic cells injection. The rats were killed after the evaluation and the spleen, brain cortex and hippocampus were excised. The red–ox state was assessed in homogenates of tissues by measuring total glutathione (GSH) content, the ferric ion reducing ability of plasma (FRAP) level, expression of heme oxygenase-1 (HO-1), biliverdin reductase (BvR) and ferritin mRNA, superoxide dismutase (SOD) activity, as well as malondialdehyde (MDA) concentration. Radioligand binding assay was used to assess of the effect of leukemia on cortical receptors. Leukemic cells were identified using RM-124 antibody by FACS Calibur flow cytometry. Leukemia influenced locomotory activity as well as forced swim test behavior in a 34-day series of experiments. Signs of oxidative stress in leukemic rats were observed in each examined stage of leukemia development. The FRAP values and glutathione contents, were significantly lowered whereas HO-1 mRNA expression, and malonodialdehyde concentrations were significantly increased in the spleen and brain structures of leukemic rats in comparison with the healthy controls. A significant increase in the potency of glycine to displace [3H]L-689,560 from the strychnine-insensitive glycine site of the N-methyl-D-aspartic (NMDA) receptors receptor complex in cortical homogenates of the leukemic rats in 30- and 34-day experimental series was observed in comparison with the control. Upregulation of 5-HT2A receptors was observed in rat cortex after 30 days of leukemia development but not in 34-days series compared with the control. It is concluded that disturbances in antioxidant system in brain cortex were accompanied by an activation of glycine sites of the NMDA receptor complex, regardless of stage of leukemia development, which are characteristic of model of depression. Findings of our study demonstrate the link between glutamatergic activity, oxidative stress and leukemia.  相似文献   
88.
Mechanisms of synaptic vesicular fusion and neurotransmitter clearance are highly controlled processes whose finely-tuned regulation is critical for neural function. This modulation has been suggested to involve pre-synaptic auto - receptors; however, their underlying mechanisms of action remain unclear. Previous studies with the well-defined C. elegans nervous system have used functional imaging to implicate acid sensing ion channels (ASIC-1) to describe synaptic vesicle fusion dynamics within its eight dopaminergic neurons. Implementing a similar imaging approach with a pH-sensitive fluorescent reporter and fluorescence resonance after photobleaching (FRAP), we analyzed dynamic imaging data collected from individual synaptic termini in live animals. We present evidence that constitutive fusion of neurotransmitter vesicles on dopaminergic synaptic termini is modulated through DOP-2 auto-receptors via a negative feedback loop. Integrating our previous results showing the role of ASIC-1 in a positive feedback loop, we also put forth an updated model for synaptic vesicle fusion in which, along with DAT-1 and ASIC-1, the dopamine auto-receptor DOP-2 lies at a modulatory hub at dopaminergic synapses. Our findings are of potential broader significance as similar mechanisms are likely to be used by auto-receptors for other small molecule neurotransmitters across species.  相似文献   
89.
Context: Sempervivum davisii Muirhead (Crassulaceae) is a traditional medicinal herb from Eastern Anatolia. To date the composition of phytochemicals and physiological properties of this herb were not subjected to any research.

Objective: This study identifies compounds in S. davisii hydrophilic extracts and evaluates their potential biological properties.

Materials and methods: Ethanol-based lyophilized extracts were obtained from aerial parts of plant (10?g of ground dry plant material in 200?mL of acidified aqueous ethanol, shaken for 2?h at 22?°C with supernatant collected and freeze-dried under vacuum). Phytochemical composition was investigated by liquid chromatography mass spectrometry (LC-MS/MS, phenolics) and gas chromatography mass spectrometry (GC-MS, volatiles). Phenolic compounds were quantified by high-performance liquid chromatography (HPLC) and the Folin–Ciocalteu assay. Subsequently, antioxidant capacity [ferric reducing antioxidant power (FRAP), oxygen radical absorbance capacity (ORAC) assays] and enzyme inhibitory properties (isolated porcine pancreatic lipase) of the extracts were determined.

Results: Polyphenolic compounds were the main constituents of lyophilized extracts, among which kaempferol glycosides and quercetin hexoside dominated. The extracts exhibited potent antioxidant (FRAP values of 1925.2–5973.3?μM Fe2+/g DW; ORAC values of 1858.5–4208.7?μM Trolox Eq./g DW) and moderate lipase inhibitory (IC50: 11.6–2.96?mg/mL) activities. Volatile compounds (nonanal, dehydroxylinalool oxide isomers, 2-decenal, 2-undecenal, 2,6-di-tetr-butylphenol) were also found.

Conclusions: Phenolic compounds with the dominating kaempferol and quercetin derivatives are the sources of potent antioxidant properties of S. davisii hydrophilic extracts. The extracts exhibit moderate inhibitory properties towards isolated pancreatic lipase.  相似文献   
90.
Excessive free radical production leading to oxidative stress may be involved in the pathophysiology of schizophrenia. Determination of total antioxidant status (TAS) provides an index of the sum of activities of all antioxidants. However, there have been few systematic studies to examine the relationship between TAS levels and psychopathology in first-episode and drug-naive patients with schizophrenia.TAS levels were determined in the plasma of 60 never-medicated first-episode patients with schizophrenia and 68 healthy control subjects. The schizophrenia symptomatology and the depressive symptoms were assessed by the positive and negative syndrome scale (PANSS) and the Hamilton rating scale for depression (HAMD). The results showed that TAS levels were significantly lower in first-episode patients with schizophrenia than in healthy control subjects (159.8 ± 45.8 U/ml vs 211.4 ± 46.8 U/ml, F = 39.5, df = 1, 126, p < 0.001). A trend toward significant inverse correlation between TAS levels and PANSS negative subscore was observed (r = 0.25, df = 60, p = 0.06). Our results suggest that oxidative stress occurs in an early course of schizophrenia and may have an important role in pathogenesis and perhaps, negative symptomatology of schizophrenia.  相似文献   
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