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1.
Marine natural products have as of now been acknowledged as the most important source of bioactive substances and drug leads. Marine flora and fauna, such as algae, bacteria, sponges, fungi, seaweeds, corals, diatoms, ascidian etc. are important resources from oceans, accounting for more than 90% of the total oceanic biomass. They are taxonomically different with huge productive and are pharmacologically active novel chemical signatures and bid a tremendous opportunity for discovery of new anti-cancer molecules. The water bodies a rich source of potent molecules which improve existence suitability and serve as chemical shield against microbes and little or huge creatures. These molecules have exhibited a range of biological properties antioxidant, antibacterial, antitumour etc. In spite of huge resources enriched with exciting chemicals, the marine floras and faunas are largely unexplored for their anticancer properties. In recent past, numerous marine anticancer compounds have been isolated, characterized, identified and are under trials for human use. In this write up we have tried to compile about marine-derived compounds anticancer biological activities of diverse flora and fauna and their underlying mechanisms and the generous raise in these compounds examined for malignant growth treatment in the course of the most recent quite a long while.  相似文献   
2.
An optimized and validated inductively coupled plasma mass spectrometry (ICP-MS) method was used to analyze trace elements in seaweeds. Different volumes and rates of HNO3 and H2O2, digestion times, and microwave power levels were tested to ascertain the best conditions for sample digestion. Analytical mass and instrumental parameters were selected to assure accurate and precise determination of As, Cd, Co, Cr, Mo, Ni, Pb, Sb, Se, and V by ICP-MS. The method was optimized and validated using biological Certified Reference Materials. In addition, some samples of seaweeds (Porphyra and Laminaria) from France, Spain, Korea, and Japan were analyzed using the optimized method. Porphyra presented higher concentrations of most elements, except for As, than Laminaria. Seaweeds from Korea and Japan tended to display the highest concentrations of Pb and Cd. In contrast, Spanish and French samples showed the highest levels of some micro-elements essential to human nutrition.  相似文献   
3.
Four methods for acid digestion of seaweeds were compared in 10 commercially available seaweeds: (i) in stainless steel-Teflon®PTFE-bombs at high pressure and temperature, (ii) in closed-Teflon®PFA-vessels at high pressure and temperature, (iii) in open-polypropylene-tubes with reflux caps in a graphite heating block at high temperature and (iv) in closed-TFM™PTFE-vessels with microwave-assisted controlled pressure and temperature. Hg was determined in all digests by cold vapour atomic fluorescence spectrometry (CV-AFS). Assessment of digestion methods was performed by comparison with the results obtained for total mercury determination by the Method EPA 7473, based on direct mercury analysis in the solid samples, and with a reference material BCR-279. The open vessel digestion system with reflux in a graphite heating block at high temperature constitutes the best choice since it was found to give the better Hg extraction (83–103%) as well as the lowest variability, being RSD < 10% for most of the studied seaweeds. A previous freeze-drying and intensive grinding was the best pre-treatment. Similar results were obtained with and without the presence of oxidizing agents (KMnO4, K2Cr2O7) and with different tube-materials (borosilicate glass, PTFE and polypropylene).  相似文献   
4.
ObjectiveTo investigate the anti-inflammatory effects of Jeju seaweeds on macrophage RAW 264.7 cells under lipopolysaccharide (LPS) stimulation.MethodsEthyl acetate fractions were prepared from five different types of Jeju seaweeds, Dictyopteris divaricata (D. divaricata), Dictyopteris prolifera (D. prolifera), Prionitis cornea (P. cornea), Grateloupia lanceolata (G. lanceolata), and Grateloupia filicina (G. filicina). They were screened for inhibitory effects on proinflammatory mediators and cytokines such as nitric oxide (NO), prostaglandin E2, tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6).ResultsOur results revealed that D. divaricata, D. prolifera, P. cornea, G. lanceolata, and G. filicina potently inhibited LPS-stimulated NO production (IC50 values were 18.0, 38.36, 38.43, 32.81 and 37.14 μg/mL, respectively). Consistent with these findings, D. divaricata, D. prolifera, P. cornea, and G. filicina also reduced the LPS-induced and prostaglandin E2 production in a concentration-dependent manner. Expectedly, they suppressed the expression of inducible NO synthase and cyclooxygenase-2 at the protein level in a dose-dependent manner in the RAW 264.7 cells, as determined by western blotting. In addition, the levels of TNF-α and IL-6, released into the medium, were also reduced by D. divaricata, D. prolifera, P. cornea, G. lanceolata, and G. filicina in a dose-dependent manner (IC50 values for TNF-α were 16.11, 28.21, 84.27, 45.52 and 74.75 μg/mL, respectively; IC50 values for IL-6 were 37.35, 80.08, 103.28, 62.53 and 84.28 μg/mL, respectively). The total phlorotannin content was measured by the Folin-Ciocalteu method and expressed as phloroglucinol equivalents. The content was 92.0 μg/mg for D. divaricata, 151.8 μg/mg for D. prolifera, 57.2 μg/mg for P. cornea, 53.0 μg/mg for G. lanceolata, and 40.2 μg/mg for G. filicina.ConclusionsThus, these findings suggest that Jeju seaweed extracts have potential therapeutic applications for inflammatory responses.  相似文献   
5.
Alzheimer's disease (AD) is the most common form of dementia, which is one of the four leading causes of death in developed nations. Until date the only symptomatic treatment for this disease is based on the “cholinergic hypothesis” where the drugs enhance acetylcholine levels in the brain by inhibiting acetylcholinesterase (AChE). In the course for screening cholinesterase inhibitors about eight seaweeds, with wide pharmaceutical applications, were collected from Hare Island, Gulf of Mannar, Marine Biosphere Reserve, Tamil Nadu, India. Inhibitory effect of methanol extract of the seaweeds was studied in vitro by incubating various concentration of the extract with AChE or butyryl cholinesterase (BuChE) and assessing their activities by Ellman's colorimetric method. Kinetic parameters like IC50, Ki and Vmax were also analyzed. The results showed that of the eight seaweeds screened Hypnea valentiae, Padina gymnospora, Ulva reticulata and Gracilaria edulis exhibited inhibitory activity to AChE with IC50 value of 2.6, 3.5, 10 and 3 mg/ml respectively, while H. valentiae, Enteromorpha intestinalis, Dictyota dichotoma and U. reticulata showed 50% inhibition to BuChE at concentration 3.9, 7, 6.5 and 10 mg/ml respectively. The inhibitory activities of the seaweed extracts were comparable to the standard drug donepezil. Enzyme kinetic analysis showed that algal extracts exhibited mixed type inhibition (partial noncompetitive inhibition).  相似文献   
6.
In order to help explain the absence of the brown kelp Lessonia nigrescens from a coastal environment chronically enriched with copper, we characterized the biochemical responses induced by copper stress in this kelp and compared them with those displayed by the copper tolerant brown alga Scytosiphon lomentaria. These algae were cultivated with increasing concentrations of copper (20, 40 and 100 μg L−1) for 96 h and the temporal production of hydrogen peroxide, superoxide anions and lipoperoxides as well as the activities of antioxidant enzymes catalase (CAT), glutathione peroxidase (GP), ascorbate peroxidase (AP), dehydroascorbate reductase (DHAR) and glutathione reductase (GR) and the activity of the defense enzyme lipoxygenase (LOX) were determined. In L. nigrescens and S. lomentaria, a single peak of hydrogen peroxide was detected, with similar maxima after 3 h of copper exposure, although in L. nigrescens buffering took longer. Superoxide anions, on the other hand, were only detected in L. nigrescens. The production of lipoperoxides in L. nigrescens increased steadily at higher copper levels, in a pattern clearly different to their rapid stabilization in S. lomentaria. We suggest that the accumulation of lipoperoxides might be related to LOX, whose activity also increases with exposure time. Furthermore, activities of the antioxidant enzymes CAT, GP, AP and DHAR were lower in L. nigrescens than in S. lomentaria, and GP and DHAR were completely inhibited at higher copper concentrations. Since these enzymes also detoxify fatty acid hydroperoxides, their inhibition, together with the activation of LOX, may explain the persistent and copper-dependent levels of lipoperoxides in L. nigrescens. Based on terrestrial plant models demonstrating toxic effects of lipoperoxides, and on our results on organellar ultrastructural changes, we suggest that copper toxicity induced an uncontrolled lipoperoxide accumulation which may lead to cell damage and dysfunction in L. nigrescens, explaining at least partially, the absence of this kelp in a copper-enriched coastal environment.  相似文献   
7.
Proximate analysis and the fatty acid profile of brown algae (Stypopodium schimperii) and red algae (Spyridia filamentosa, Acanthophora nayadiformis and Halymenia floresii) were investigated. The highest protein content was obtained from H. floresii (3.05% on a dry weight basis) whereas the lowest protein content was obtained from S. schimperii (1.12% dry weight). The lipid content of macro algae ranged from 1.10% for S. filamentosa to 11.53% dry weight for S. schimperii. The ash content of all algae species were found to be high (17.98–27.15%) on a dry weight basis. The fatty acid compositions of macro algae species were in the range 29.92–68.93% saturated, 17.88–39.23% monounsaturated and 6.0–17.57% polyunsaturated acids. Among them, those occurring in the highest proportions were palmitic acid (C16:0, 28.36–64.67%), myristoleic acid (C14:1, 5.54–6.7%), palmitoleic acid (C16:1, 3.33–19.51%), oleic acid (C18:1n9 cis, 6.62–13.92%), linoleic acid (C18:2n6, 1.03–4.65%), arachidonic acid (C20:4n6, 1.2–6.9%), and cis-5,8,11,14,17-eicosapentaenoic acid (C20:5n3, 1.07–9.89%). According to results obtained from this study, these macro algae species can be regarded as a potential source for food or the neutraceutical industry.  相似文献   
8.
24种海藻中脂肪酸含量的研究   总被引:10,自引:1,他引:9  
用气相色谱法分析了24种不同门类海藻脂肪的含量,结果表明,海藻脂肪酸以棕榈酸含量最高,约占总量的40%,按分类比较,褐藻门海藻的脂肪酸总量及不饱和脂肪酸的含量都较高,而红藻门,绿藻门海藻的脂肪酸含量较低。  相似文献   
9.
大连旅顺沿海17种经济海藻微量元素的ICP测定   总被引:3,自引:0,他引:3  
目的:测定大连市旅顺沿海17种常见经济海藻中人体必需微量元素的含量。方法:用高频电感耦合等离子(ICP)光谱技术测定。结果:17种海藻中人体必需微量元素(如Ca、Zn、Fe等)含量丰富,绿藻门中微量元素含量相对较高。结论:为综合利用海藻中各种微量元素,使其发挥更好的作用,提供了科学依据。  相似文献   
10.
Seaweed extracts have recently been found to have antioxidant and antitumor activities. Capsosiphon fulvescens (Cf) is a green alga and nutrient-dense food source. In a previous study, we extracted polysaccharide from Cf (Cf-PS) and demonstrated its antitumor effect in gastric cancer cells. In this report, we describe the protective effect of Cf-PS against alcohol-induced gastric injury in rats and adenocarcinoma (AGS) cells. In vivo assay revealed stomach damage in rats treated with alcohol alone; however, the stomach condition of rats co-treated with Cf-PS and alcohol matched that of the control group. Cf-PS also inhibited alcohol-induced cell death in AGS cells. Compared with alcohol treatment alone, Cf-PS and alcohol co-treatment increased phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2) and Akt but inhibited poly-ADP-ribose polymerase (PARP) cleavage. Thus, ERK1/2 and Akt activation are instrumental in the protective effect of Cf-PS against alcohol-induced cell death in AGS cells. Moreover, Cf-PS treatment reduced the expressions of cyclooxygenase-2 (COX-2) and the inducible form of nitric oxide (iNOS), proteins related to ulcers. These results suggest that Cf-PS could help protect against alcohol-induced peptic ulcers.  相似文献   
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