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1.
Schiff bases (imines or azomethines) are versatile ligands synthesized from the condensation of amino compounds with active carbonyl groups and used for many pharmaceutical and medicinal applications. In our study, we aimed to determine the cytotoxic, antifungal and larvicidal activities of biologically potent bis-sulfonamide Schiff base derivatives that were re-synthesized by us. For this aim, 16 compounds were re-synthesized and tested for their cytotoxic, antifungal and larvicidal properties. Among this series, compounds A1B2 , A1B4 , A4B2 , A4B3 , and A4B4 were shown to have cytotoxic activity against tested cancer lung cell line (A549). The most potent antifungal activity was observed in compounds A2B1 and A2B2 against all fungi. A1B1 showed the strongest larvicidal effect at all concentrations at the 72nd h (100% mortality). These obtained results demonstrate that these type of bis-substituted compounds might be used as biologically potent pharmacophores against different types of diseases.  相似文献   
2.
Sunflower honey (SH) is bright yellow, fragrant, pollen-flavoured, slightly herbaceous and has a unique taste. The present research aims to examine the enzyme inhibitory, antioxidant, anti-inflammatory, antimicrobial and anti-quorum sensing activities and phenolic compositions of 30 sunflower honeys (SHs) produced from several regions of Turkey with chemometric study. SAH from Samsun exhibited the best antioxidant activity in β-carotene linoleic acid (IC50: 7.33±0.17 mg/mL) and CUPRAC (A0.50: 4.94±0.13 mg/mL) assays, anti-urease activity (60.63±0.87 %) and anti-inflammatory activity against COX-1 (73.94±1.08 %) and COX-2 (44.96±0.85 %). SHs exhibited mild antimicrobial activity against the test microorganisms while they showed high quorum sensing inhibition zones measured in the range of 42–52 mm against the CV026 strain. The phenolic composition was determined by high performance liquid chromatography with diode array detection (HPLC-DAD) system and levulinic, gallic, p-hydroxybenzoic, vanillic and p-coumaric acids were identified in all studied SHs. The classification of SHs was performed the using PCA and HCA. This study revealed that phenolic compounds and biological properties are effective in classification of SHs according to their geographical origin. The results suggest that studied SHs could be valued as potential agents with versatile bioactivities in oxidative stress-related disease, microbial infections, inflammation, melanoma, and peptic ulcer.  相似文献   
3.
The structure and function of the centrosomes from Chinese hamster ovary (CHO) cells were investigated by electron microscopy of negatively stained wholemount preparations of cell lysates. Cells were trypsinized from culture dishes, lysed with Triton X-100, sedimented onto ionized, carbon-coated grids, and negatively stained with phosphotungstate. The centrosomes from both interphase and dividing cells consisted of pairs of centrioles, a fibrous pericentriolar material, and a group of virus-like particles which were characteristic of the CHO cells and which served as markers for the pericentriolar material. Interphase centrosomes anchored up to two dozen microtubules when cells were lysed under conditions which preserved native microtubules. When Colcemid-blocked mitotic cells, initially devoid of microtubules, were allowed to recover for 10 min, microtubules formed at the pericentriolar material, but not at the centrioles. When lysates of Colcemid-blocked cells were incubated in vitro with micotubule protein purified from porcine brain tissue, up to 250 microtubules assembled at the centrosomes, similar to the number of microtubules that would normally form at the centrosome during cell division. A few microtubules could also be assembled in vitro onto the ends of isolated centrioles from which the pericentriolar material had been removed, forming characteristic axoneme- like bundles. In addition, microtubules; were assembled onto fragments of densely staining, fibrous material which was tentatively identified as periocentriolar material by its association of CHO can initiate and anchor microtubules both in vivo and in vitro.  相似文献   
4.

Aims

Heat stress is a growing concern in crop production because of global warming. In many cropping systems heat stress often occurs simultaneously with other environmental stress factors such as mineral nutrient deficiencies. This study aimed to investigate the role of adequate magnesium (Mg) nutrition in mitigating the detrimental effects of heat stress on wheat (Triticum aestivum) and maize (Zea mays).

Methods

Wheat and maize plants were grown in solution culture with low or adequate Mg supply at 25/22 °C (light/dark). Half of the plants were, then, exposed to heat stress at 35/28 °C (light/dark). Development of leaf chlorosis and changes in root and shoot growth, chlorophyll and Mg concentrations as well as the activities of major antioxidative enzymes were quantified in the experimental plants. Additionally, maize plants were analyzed for the specific weights (e.g., dry or fresh weight per a given leaf surface area) and soluble carbohydrate concentrations of sink and source leaves.

Results

Visual leaf symptoms of Mg deficiency were aggravated in wheat and maize when exposed to heat stress. In both species, root growth was more sensitive to Mg deficiency than shoot growth, and the shoot-to-root ratios peaked when heat stress was combined with Mg deficiency. Magnesium deficiency markedly reduced soluble carbohydrate concentrations in young leaf; but resulted in substantial increase in source leaves. Magnesium deficiency also increased activities of antioxidative enzymes, especially when combined with heat stress. The highest activities of superoxide dismutase (up to 80 % above the control), glutathione reductase (up to 250 % above the control) and ascorbate peroxidase (up to 300 % above the control) were measured when Mg-deficient plants were subjected to heat, indicating stimulated formation of reactive oxygen species (ROS) in Mg deficient leaves under heat stress.

Conclusions

Magnesium deficiency increases susceptibility of wheat and maize plants to heat stress, probably by increasing oxidative cellular damage caused by ROS. Ensuring a sufficiently high Mg supply for crop plants through Mg fertilization is a critical factor for minimizing heat-related losses in crop production.  相似文献   
5.
Plant-based foods have become attractive for scientists and food producers. Beneficial effects related to their consumption as dietary supplements are due to the presence of natural occurring secondary metabolites. In this context, studies on these products are important for natural and safely food ingredients evaluation. The aim of this study was to evaluate root extract of eight Asphodeline species as antioxidants, enzyme inhibitors and phytochemical content. Spectrophotometric antioxidant and enzyme inhibitory assays were performed. Total phenolic and flavonoids contents as well as the chemical free-anthraquinones profiles were determined using routinely procedure (HPLC-PDA). Data show that Asphodeline roots can be considered as a new source of natural compounds and can be used as a valuable dietary supplement. Some differences related to biological activities can be inferred to other phytochemicals that can be considered in the future for their synergic or competitive activities.  相似文献   
6.
Role of β3-AR dysregulation, as either cardio-conserving or cardio-disrupting mediator, remains unknown yet. Therefore, we examined the molecular mechanism of β3-AR activation in depressed myocardial contractility using a specific agonist CL316243 or using β3-AR overexpressed cardiomyocytes. Since it has been previously shown a possible correlation between increased cellular free Zn2+ ([Zn2+]i) and depressed cardiac contractility, we first demonstrated a relation between β3-AR activation and increased [Zn2+]i, parallel to the significant depolarization in mitochondrial membrane potential in rat ventricular cardiomyocytes. Furthermore, the increased [Zn2+]i induced a significant increase in messenger RNA (mRNA) level of β3-AR in cardiomyocytes. Either β3-AR activation or its overexpression could increase cellular reactive oxygen species (ROS) and reactive nitrogen species (RNS) levels, in line with significant changes in nitric oxide (NO)-pathway, including increases in the ratios of pNOS3/NOS3 and pGSK-3β/GSK-3β, and PKG expression level in cardiomyocytes. Although β3-AR activation induced depression in both Na+- and Ca2+-currents, the prolonged action potential (AP) seems to be associated with a marked depression in K+-currents. The β3-AR activation caused a negative inotropic effect on the mechanical activity of the heart, through affecting the cellular Ca2+-handling, including its effect on Ca2+-leakage from sarcoplasmic reticulum (SR). Our cellular level data with β3-AR agonism were supported with the data on high [Zn2+]i and β3-AR protein-level in metabolic syndrome (MetS)-rat heart. Overall, our present data can emphasize the important deleterious effect of β3-AR activation in cardiac remodeling under pathological condition, at least, through a cross-link between β3-AR activation, NO-signaling, and [Zn2+]i pathways. Moreover, it is interesting to note that the recovery in ER-stress markers with β3-AR agonism in hyperglycemic cardiomyocytes is favored. Therefore, how long and to which level the β3-AR agonism would be friend or become foe remains to be mystery, yet.  相似文献   
7.
Lipid disorders and increased oxidative stress may exacerbate some complications of diabetes mellitus. Previous studies have implicated the beneficial effects of some antioxidants, omega-3 polyunsaturated fatty acids (PUFAs), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in the protection of cells from the destructive effect of increased lipids and lipid peroxidation products. This study, therefore, was designed to investigate the effects of cod liver oil (CLO, Lysi Ltd. Island), which comprises mainly vitamin A, PUFAs, EPA and DHA. Effects were monitored on plasma lipids, lipid peroxidation products (MDA) and the activities of antioxidant enzymes, glutathione peroxidase (GSHPx) and catalase in heart, liver, kidney and lung of non-diabetic control and streptozotocin (STZ)-induced-diabetic rats. Two days after STZ-injection (55 mg kg(-1) i.p.), non-diabetic control and diabetic rats were divided randomly into two groups as untreated or treated with CLO (0.5 ml kg(-1) rat per day) for 12 weeks. Plasma glucose, triacylglycerol and cholesterol concentrations were significantly elevated in 12-week untreated-diabetic animals; CLO treatment almost completely prevented these abnormalities in triacylglycerol and cholesterol, but hyperglycaemia was partially controlled. CLO also provided better weight gain in diabetic animals. In untreated diabetic rats, MDA markedly increased in aorta, heart and liver but was not significantly changed in kidney and lung. This was accompanied by a significant increase in both GSHPx and catalase enzyme activities in aorta, heart, and liver of diabetic rats. In kidney and lung, diabetes resulted in reduced catalase while GSHPx was significantly activated. In aorta, heart, and liver, diabetes-induced changes in MDA were entirely prevented by CLO treatment. In the tissues of CLO-treated diabetic animals, GSHPx activity paralleled those of control animals. CLO treatment also caused significant improvements in catalase activities in every tissue of diabetic rats, but failed to affect MDA and antioxidant activity in control animals. The current study suggests that the treatment of diabetic rats with CLO provides better control of glucose and lipid metabolism, allows recovery of normal growth rate, prevents oxidative/peroxidative stress and ameliorates endogenous antioxidant enzyme activities in various tissues. Because CLO contains a plethora of beneficial compounds together, its use for the management of diabetes-induced complications may provide important advantages.  相似文献   
8.
啤酒多倍体酵母菌原生质体已成功地与单倍体原生质体进行融合。经细胞壁再生后,稳定的融合重组体被分离出来。这些融合体的基因分析表明,融合体中含有双亲的基因型。孢子形成良好,且每个子囊中含有四个孢子,每个孢子确实是二倍体。这样原生质体融合就提供了一个对啤酒酿造酵母进行遗传分析的方法。但是如果没有一个方便的杂交技术,这个方法将是很困难的。  相似文献   
9.
Fifteen chromonylrhodamine derivatives (CRs) were synthesized and the antioxidant activity levels were evaluated for the first time. The antioxidant activity potencies of these chromone derivatives were evaluated towards superoxide anion radicals, hydroxyl radicals and 2,2‐diphenyl‐1‐picrylhydrazyl radicals. Also, the total antioxidant capacity of the tested compounds was measured using the ferric‐ferrozine assay. The antioxidant activities were investigated using a chemiluminescence (CL) assay, spectrophotometry measurements, direct electron paramagnetic resonance (EPR) and the EPR spin‐trapping technique. The 5,5‐dimethyl‐ 1‐pyrroline‐1‐oxide (DMPO) was applied as spin trap. Eleven of the 15 chromone compounds exhibited a decrease in the CL accompanying the superoxide anion radical produced in anhydrous dimethylsulfoxide (DMSO), ranging from 71–94% at concentration of 1 mmol /L; four of these compounds enhanced light emission in the range 231–672%. Similarly, these compounds caused 28–58% inhibition in the intensity of the DMPO‐OOH radical EPR signal and the DMPO‐OH radical (from 12–48%). Furthermore, three of these compounds showed very good antioxidant response towards the DPPH radical (EC50: 0.51–0.56 µmol/L) and the high reduction potentials. These findings demonstrate that the chromone compounds tested may be considered as effective free radicals scavengers, a finding that is of great pharmacological importance. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
10.
In this study, two different semen cryopreservation protocols were compared to freeze goat semen. The ejaculates (n = 12) were collected by using electro-ejaculator from six mature bucks (two ejaculates per each buck). Each ejaculate was divided into two groups as Protocol 1 (P1) and Protocol 2 (P2). In P1, semen was diluted directly in an extender containing 15% egg yolk, 300 mM Tris, 28 mM glucose, 95 mM citric acid 5% glycerol to a concentration of 200 × 106 sperm/mL. In P2, after the removal of seminal plasma by centrifugation, the semen sample was diluted with the first portion of milk extender consist of 100 mg/mL skimmed milk powder and 27.75 mM glucose (without glycerol) to a concentration of 400 × 106 sperm/mL. The second portion of the milk extender containing 14% glycerol was added to semen gradually in order to achieve sperm concentration 200 × 106 sperm/mL and 7% glycerol level in the final volume. Extended semen was loaded in 0.25 mL straws, held for 2 h at 4 °C, frozen in nitrogen vapor and stored in liquid nitrogen. Post-thaw motility and live sperm rate (mean ± SEM) were significantly lower (P < 0.05) in P1 as compared to P2 (47.50 ± 1.23% vs. 55.63 ± 1.72%; 80.04 ± 1.29% vs. 84.04 ± 1.08%, respectively). However, live intact, total intact, abnormal, reacted acrosome and DNA damaged sperm rates were similar (P > 0.05) in both protocols. It was concluded that both protocols used in this study provided reasonable post-thaw parameters; however, P2 yielded better motility and live sperm rate compared to P1.  相似文献   
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