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1.
Social attachment is vital for human health and welfare. Recent experimental evidence in humans has identified the role of neuroactive hormones, especially the peptide oxytocin, in mediating trusting behaviors. Herein, we test if the endocrinological basis for trust between humans scales up to the country level. Trust pervades nearly every aspect of our daily lives, yet survey data on trust show substantial variation across countries. Using 31 measures of biological, social, and environmental factors associated with hormone levels for a sample of 41 countries, we find that two classes of factors are related to trust: consumption of plant-based estrogens (phytoestrogens), and the presence of environmental conditions that include measures of estrogen-like molecules. Our findings provide preliminary evidence that interpersonal trust at the country level may be related to the intake of neuroactive hormones.  相似文献   
2.
The genus Lavandula is known for its different uses in traditional medicine. This study is interested in the chemical composition of Lavandulapedunculata subsp.atlantica (Braun‐Blanq. ) Romo as well as evaluating its antibacterial potential against multi‐resistant strains. The analysis of Lavandulaatlantica essential oil (LAEO) allows the identification of 47 components representing 93.6 % of all identified. The main constituent of LAEO was camphor (50.4 %), followed by fenchone (14.1 %) and camphene (5.6 %). The antibacterial assays revealed that LAEO was active against all the studied bacteria. A preliminary study of the relationship between certain terpenoids and antibacterial activity was also carried out in order to note the compound(s) that are responsible for LAEO's antibacterial activity. This study showed that the activity of the essential oil may be due to the presence of certain minor compounds such as carvone, considering the presence of the synergistic effect between the essential oil.  相似文献   
3.
The myogenic behaviour of primary human muscle precursor cells (MPCs) obtained from young (aged 20–25 years) and elderly people (aged 67–82 years) was studied in culture. Cells were compared in terms of proliferation, DNA damage, time course and extent of myogenic marker expression during differentiation, fusion, size of the formed myotubes, secretion of the myogenic regulatory cytokine TGF‐β1 and sensitivity to TGF‐β1 treatment. No differences were observed between cells obtained from the young and elderly people. The cell populations were expanded in culture until replicative senescence. Cultures that maintained their initial proportion of myogenic cells (desmin positive) with passaging (n = 5) were studied and compared with cells from the same individuals in the non‐senescent state. The senescent cells exhibited a greater number of cells with DNA damage (γ‐H2AX positive), showed impaired expression of markers of differentiation, fused less well, formed smaller myotubes and secreted more TGF‐β. The data strongly suggest that MPCs from young and elderly people have similar myogenic behaviour.  相似文献   
4.
Biological Trace Element Research - The efficacy of Moringa oleifera leaf extract (MO) in alleviating nephrotoxicity induced by titanium dioxide nanoparticles (TiO2 NPs) was studied. Rats were...  相似文献   
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6.
Iron saccharate complex ISC is an iron supplement used to optimize erythropoiesis in cases of iron deficiencies. Because of the lack of major mechanisms of iron excretion, excess iron unbound to protective molecules is believed to be involved in catalyzing the generation of reactive oxygen species and induction of oxidative stress. This study employed ISC for the purpose of inducing iron overload and hence investigating the consequent iron toxicity, lipid peroxidation and antioxidant extent in a murine species. Male Wistar rats were given iron as intraperitoneal injections of ISC in subacute (0.2 mg Fe kg?1 for 2 weeks) and subchronic (0.1 mg Fe kg?1 for 4 weeks) doses. In iron-overloaded rats, enhanced hepatic iron accumulation (P > 0.001) attended by increased serum concentrations of malondialdehyde (MDA) (P > 0.001) and activities of antioxidant enzymes (superoxide dismutase SOD, catalase CAT and glutathione peroxidase GPx) (P > 0.001) was pointed out. The demonstrated antioxidant boost is attributed to a sense of equilibrium prompted by the potential of iron-induced oxidative stress to modify antioxidant defense capacity and to modulate susceptibility to oxidative stress. Rats seemed to constantly suffer from oxidative stress based on the consistent rise in MDA that was not overwhelmed by the elevated antioxidant input. The current findings are of informative value in drawing attention to the health hazards of applying higher doses of the commercially used iron supplement ISC. Data are virtually significant in elucidating the higher magnitude of subchronic than subacute iron overload in initiating oxidative stress and antioxidant defense. Both pathways proceeded in a time-dependent rather than dose-dependent manner.  相似文献   
7.
Abstract:  When the kalotermitid Kalotermes flavicollis Fabr. pseudergates exposed to Casuarina wood wafers treated separately with different concentrations (5, 15 and 30  μ l/2 g wood wafer) of the essential oils, their spirochaete and flagellate populations abnormally reduced in numbers and vigour. The lophomonadids Joenia sp. and Mesojoenia sp. were the most adversely affected flagellates followed by the polymastigid Foaina sp. and the trichomonadid Tricercomitus sp. The Taxodium distichum essential oil evidently appeared to have the greatest adverse effect on the flagellates (95–100% decline in numbers within 2–4 days) followed by the Eucalyptus citriodora (89–100%) and the Cupressus sempervirens oils (31–100%). While with the hindgut spirochaetes, the adverse effect seemed to be reversed where the E. citriodora essential oil had the greatest effect (54–100%) followed by C. sempervirens (46–100%) and T. distichum (8–100%) oils. Moreover, the essential oils were assayed for their antifungal activity, at 15, 20, 25, 30, and 50  μ l/1 ml acetone/15 ml Czapek-Dox medium, against isolates of four woodrotting fungi associated with Casuarina timber, Aspergillus sp., Penicillium sp., Fusarium sp. and Mucor sp. by a method based on inhibition of the fungus growth on agar plates. E. citriodora exhibited the most potent fungicidal activity against the tested four fungi, followed by T. distichum oil. While the C. sempervirens essential oil appeared to have the least significant antifungal property.  相似文献   
8.
Investigation was carried out to find whether enhanced ultraviolet radiation influences the Malva parviflora L., Plantago major L., Rumex vesicarius L. and Sismbrium erysimoids Desf. of some annual desert plants. The seeds were grown in plastic pots equally filled with a pre-sieved normal sandy soil for 1 month. The planted pots from each species were randomly divided into equal groups (three groups). Plants of the first group exposed to white-light tubes (400–700 nm) 60 w and UV (365 nm) 8 w tubes. The second group was exposed to white-light tubes (400–700 nm) 60 w and UV (302 nm) 8 w tubes. The third group was exposed to white-light tubes (400–700 nm) 60 w and UV (254 nm) 8 w tubes, respectively, for six days. The results indicated that the chlorophyll contents were affected by enhanced UV radiation. The chlorophyll a, b, and total contents were decreased compared with the control values and reduced with the enhanced UV radiation, but the carotenoid was increased compared with the control and also reduced with the enhanced UV radiation. So, the contents of chlorophylls varied considerably. M. parviflora showed the highest constitutive levels of accumulated chlorophyll a, b, and total chlorophyll (0.463, 0.307 and 0.774 mg g−1 f w) among the investigated plant species. P. major showed the lowest constitutive levels of the chloroplast pigments, 0.0036, 0.0038 and 0.0075 mg g−1 f w for chlorophyll a, b, and total chlorophyll at UV-365 nm, respectively. The protein content was decreased significantly in both root and shoot systems compared with the control values but, it was increased with increasing wave lengths of UV-radiation of all tested plants. R. vesicarius showed the highest protein contents among the investigated plants; its content was 3.8 mg g−1 f w at UV-365 nm in shoot system. On the other hand, decreasing ultraviolet wave length induced a highly significant increase in the level of proline in both root and shoot of all tested plants. From the results obtained, it is suggested that proline can protect cells against damage induced by ultraviolet radiation. Statistically, the variations of the studied metabolic activities were significant due to UV radiation treatment in shoot and root system of all investigated plant species.  相似文献   
9.
Carbacylamidophosphates with the general formula RC(O)NHP(O)R1R2 constitute organophosphorus compounds that are used as insecticides, pesticides and ureas inhibitors. In this work, we studied the inhibition potency of CCl3-C(O)NHP(O)Cl21, CHCl2C(O)NHP(O)Cl(2)2, CH2ClC(O)NHP(O)Cl23 and CF3C(O)NHP(O)Cl(2)4, which are the major intermediates for carbacylamidophosphates synthesis towards human erythrocyte acetylcholinesterase (hAChe) activity using Ellman's modified kinetic method. Unexpectedly, it was observed that they were not only hydrolytically unstable but also inhibited hAChE in a similar manner to that produced by organophosphorus insecticides. Enzymatic data, bimolecular inhibition rate constants (ki) and IC50 values for inhibition of hAChE demonstrated that they are irreversible inhibitors and the inhibition potency of compound 2 (IC50 = 88 microM) was the greatest in comparison with compounds 1, 3 and 4. Also the electropositivity of the phosphorus atom and the hydrophobicity of the compounds demonstrated that these two factors play an additional effect and different role in the inhibitory activity of these compounds. Hydrolytic stability of the compounds was determined by 31P NMR monitoring of the loss of the parent molecules with D2O as a function of time. This study considers antiacetylcholinesterase activity according to the structural and the electronic aspects of compounds 1-4, according to IR, 1H, 13C and 31P NMR spectral data.  相似文献   
10.
Liver fibrosis is a major health problem that can lead to the development of liver cirrhosis and hepatocellular carcinoma. On the other hand, several antioxidants have been shown to possess protective effect against liver fibrosis. Therefore, in the present work, the effectiveness of curcumin, α-lipoic acid, and N-acetylcysteine in protecting against carbon tetrachloride (CCl4)-induced liver fibrosis as well as the mechanism(s) implicated in this protective effect was studied. The antioxidants used in this study resulted in hepatoprotective effect as evident by substantial decreases in collagen deposition in histopathological examinations in addition to significant decrease in serum levels of alanine aminotransferase, aspartate aminotransferase, gamma glutamyl transpeptidase, bilirubin, and transforming growth factor-alpha (TGF-α) as well as hepatic malondialdehyde concentration, with a concurrent increase in serum matrix metalloproteinase-13 (MMP-13) and hepatic reduced glutathione (GSH) levels as compared to CCl4 fibrotic group. In conclusion, curcumin, α-lipoic acid, and N-acetylcysteine protect rats against CCl4-induced liver fibrosis most possibly through their antioxidant activities and their capacities to induce MMP-13 and to inhibit TGF-α levels.  相似文献   
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