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排序方式: 共有94条查询结果,搜索用时 31 毫秒
1.
The effects of Duranta repens fruits were investigated on H2O2 induced oxidative cell death to evaluate its antioxidative potential in vitro. HEK293T cells were treated with different concentrations [0–1000 µg/ ml] of ethanol extract (E-Ex) and methanol extract (M-Ex) of D. repens for 24h, and then treated with 100 µM H2O2 for 24h. Cell viability, antioxidant parameters of cells, and antioxidant constituents of the extracts were determined. Treatment with limited dose of E-Ex or M-Ex increased the survival rate of H2O2-treated HEK293T cells, however the extra-high dose showed growth inhibitory effect. Treatment with E-Ex or M-Ex protected cellular lipid per-oxidation. In vitro analyses showed the 2,2-diphenyl-1-picrylhydrazyl and H2O2 scavenging activities as well as reducing potential of the extracts. We report here that the limited dose of E-Ex and M-Ex possess antioxidative potential, which can protect H2O2-induced oxidative cell damage.  相似文献   
2.
《药学学报(英文版)》2020,10(3):399-413
Activated pancreatic stellate cells (PSCs) have been widely accepted as a key precursor of excessive pancreatic fibrosis, which is a crucial hallmark of chronic pancreatitis (CP) and its formidable associated disease, pancreatic cancer (PC). Hence, anti-fibrotic therapy has been identified as a novel therapeutic strategy for treating CP and PC by targeting PSCs. Most of the anti-fibrotic agents have been limited to phase I/II clinical trials involving vitamin analogs, which are abundant in medicinal plants and have proved to be promising for clinical application. The use of phytomedicines, as new anti-fibrotic agents, has been applied to a variety of complementary and alternative approaches. The aim of this review was to present a focused update on the selective new potential anti-fibrotic agents, including curcumin, resveratrol, rhein, emodin, green tea catechin derivatives, metformin, eruberin A, and ellagic acid, in combating PSC in CP and PC models. It aimed to describe the mechanism(s) of the phytochemicals used, either alone or in combination, and the associated molecular targets. Most of them were tested in PC models with similar mechanism of actions, and curcumin was tested intensively. Future research may explore the issues of bioavailability, drug design, and nano-formulation, in order to achieve successful clinical outcomes with promising activity and tolerability.  相似文献   
3.

Objective

To assess antioxidant activities of different aerial parts of Thymelaea hirsuta (T. hirsuta) from west Algeria, and to search for new sources of safe and inexpensive antioxidants.

Methods

Samples of leaves, stems and flowers from T. hirsuta were tested for total phenolic content, flavonoids content, and evaluation its total antioxidant activity, were done using the spectrophotometric analyses.

Results

Results of preliminary phytochemical screening of leaf, flower and stem of T. hirsuta revealed the presence of tannins, alkaloids, steroids, saponins, coumarins, reducteurs compound and anthraquinones. The total phenolics and flavonoids were estimated. The aqueous extracts of the aerial parts of T. hirsuta showed potent in vitro antioxydant activities using various models viz, DPPH scavenging assay, ferric reducing antioxidant power (FRAP) and ABTS radical scavenging activity.

Conclusions

On the basis of the results obtained, T. hirsuta extracts are rich sources of natural antioxidants appears to be an alternative to synthetic antioxidants and this justifies its therapeutic usage.  相似文献   
4.
Introduction: Colloidal drug delivery systems (CDDSs) are innovative carriers that have been studied in pharmaceutical field from many years to overcome unfavorable physical and chemical features of synthetic drugs. Recently the use of CDDS as carriers for phytochemicals has seen an exponential increase which, in some cases, has led to the rediscovery of ancient and forgotten natural molecules.

Area covered: This article focuses on the main features of CDDS, particularly micro- and nanoemulsions, vesicular carriers and micro- and nanoparticles, loaded with natural active compounds. A detailed review of the literature is presented, introducing the importance of these systems in terms of their capability to optimize the stability of phytochemicals, their absorption through biological membranes and their bioavailability.

Expert opinion: The delivery of phytochemicals is problematic due to poor solubility, poor permeability, low bioavailability, instability in biological milieu and extensive first-pass metabolism. Global research efforts investigating nanotechnology have attempted to overcome these limitations rediscovering and, in some cases, ‘discovering ex novo’ unexpected virtues and benefits associated to these compounds. The ‘nanotechnological approach’ can definitely enhance the pharmacokinetics and therapeutic index of natural active compounds and improve their performance in therapy.  相似文献   

5.
6.
Black cumin (Nigella sativa L.) is unique in its nutritional profile and it’s fixed and essential oils are phytochemicals rich fractions. However, safety assessment is required before recommending their use. This study was designed to evaluate the safety of black cumin fixed oil (BCFO) and black cumin essential oil (BCEO) through animal modeling using Sprague dawley rats as test animals. The results indicated that BCFO @ 4.0% and BCEO @ 0.30% are safe as serological indices like liver and kidney functioning tests, serum protein profile, level of cardiac enzymes, electrolytes balance were remained in the normal ranges even after 56 days of study. Similarly, indices of red and white blood cells remained within the defined limits. Moreover, diets were insignificant in their impression regarding organs to body weight ratio. However, group of rats fed on BCFO gained less weight as compared to control that shows slight anorexic effect of BCFO which can be useful in obesity related disorders. In the nutshell, presence of phytochemicals in black cumin fixed and essential oils as well as their safe status can positively be used against lifestyle disorders.  相似文献   
7.
Tumor metastasis is responsible for most cancer deaths, and can occur after long periods of tumor dormancy. Information learned from experimental studies on tumor metastasis and dormancy is shedding light on mechanisms responsible and possible therapeutic approaches. ‘Seed’ (the cancer cell) and ‘soil’ (the microenvironment of the secondary organ) factors contribute to metastatic outcome. This review considers the possibility that various dietary components may affect both ‘seed’ and ‘soil’ compartments, thereby influencing the growth of metastases, and discusses an experimental study on dietary genistein that illustrates this concept. While studies on human diet are complex, the possibility that relatively non-toxic dietary intervention strategies could impact on metastasis and patient survival is attractive and worthy of further study in appropriate experimental models of metastasis and tumor dormancy.  相似文献   
8.
ObjectiveTo study the phytochemical and biological properties (antioxidant, anthelmintic and thrombolytic) of methanolic extracts of Enhydra fluctuans Lour., a plant belonging to the Asteraceae family.MethodsThe phytochemical evaluation was carried out by qualitative analysis. In vitro antioxidant activity of extract was studied using free radical scavenging assay, ability of reduction, total phenol and total flavonoid contents determination assays. The anthelmintic activity was determined using paralysis and death time of Pheretima posthuma (earthworm) and thrombolytic activity by clot disruption assay.ResultsThe phytochemical evaluation showed significant presence of flavonoids, triterpenes, carbohydrate, reducing sugars, saponins, phenols, diterpenes, protein and tannin. The antioxidant activity was found significant [IC50=(135.20±0.56) μg/mL] as compared to ascorbic acid [(130.00±0.76) µg/mL]. The reducing power was increased with concentration. Total phenol and total flavonoid contents were (153.08±0.38) mg/mL and (172.04±0.56) mg/mL respectively. The paralysis and death time of earthworms for different concentrations of extract were determined and compared with albendazole. The results showed that 10 mg/mL of the crude extract had similar effect with albendazole. Additionally, the crude extract showed a concentration depended relationship with its anthelmintic property. The clot lysis activity of crude extract was compared to the standard streptokinase's clot lysis (40.13%) activity and found significant (31%).ConclusionsThe study proves that the crude methanolic extract of Enhydra fluctuans Lour. has significant antioxidant, anthelmintic and thrombolytic activity containing wide range of phytochemicals.  相似文献   
9.
10.
Sun J  Hai Liu R 《Cancer letters》2006,241(1):124-134
Breast cancer is the most commonly diagnosed cancer in women in the US and is one of the leading causes of death due to cancer. Epidemiological studies have consistently suggested the inverse association between cancer risk and intake of fruits and vegetables. These health benefits have been linked to the additive and synergistic combination of phytochemicals in fruits and vegetables. Cranberries have been shown to possess anti-carcinogenic activities such as inhibition of growth of several cancer cell lines, and inhibition of ornithine decarboxylase (ODC) activity in vitro. However, the molecular mechanisms of the anti-cancer properties of cranberry phytochemical extracts have not been completely understood. Our data showed that cranberry phytochemical extracts significantly inhibited human breast cancer MCF-7 cell proliferation at doses of 5 to 30mg/mL (P<0.05). Apoptotic induction in MCF-7 cells was observed in a dose-dependent manner after exposure to cranberry phytochemical extracts for 4h. Cranberry phytochemical extracts at a dose of 50mg/mL resulted in a 25% higher ratio of apoptotic cells to total cells as compared to the control groups (P<0.05). Cranberry phytochemical extracts at doses from 10 to 50mg/mL significantly arrested MCF-7 cells at G0/G1 phase (P<0.05). A constant increasing pattern of the G1/S index was observed in the cranberry extract treatment group while the G1/S ratio of the control group decreased concomitantly between 10 and 24h treatment. After 24-h exposure to cranberry extracts, the G1/S index of MCF-7 cells was approximately 6 times higher than that of the control group (P<0.05). These results suggest that cranberry phytochemical extracts possess the ability to suppress the proliferation of human breast cancer MCF-7 cells and this suppression is at least partly attributed to both the initiation of apoptosis and the G1 phase arrest.  相似文献   
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