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71.
72.
Two novel copper (II) complexes [Cu(TFP)(Gly)Cl] ⋅ 2H2O complex ( 1 ) and [Cu(TFP)(His)Cl] ⋅ 2H2O complex ( 2 ) are synthesized, where TFP stands for trifluropromazine, Gly. represents glycine, and His. is histidine. Chemical composition, IR, mass spectra, and magnetic susceptibility tests are performed. Complex binding with macromolecules was investigated using UV-vis, viscosity, gel electrophoresis, and fluorescence quenching. Fluorescence spectroscopy revealed that each complex could replace ethidium bromide (EB). These complexes exhibit grooved, non-covalent, and electrostatic interactions with CT-DNA. Spectroscopy analysis of the BSA interaction showed that complexes bind to protein (Kb values for ( 1 ) is 5.89×103 M−1 and for ( 2 ) is 9.08×103 M−1) more strongly than CT-DNA (Kb values for ( 1 ) is 5.43×103 M−1 and for ( 2 ) is 7.17×103 M−1). Molecular docking analysis and spectral absorption measurements showed high agreement. Antimicrobial, antioxidant, and anti-inflammatory properties were tested in vitro. The druggability of complex ( 2 ) should be tested in vivo as it is more biologically active.  相似文献   
73.
A l M usallam , A.A. & R adwan , S.S. 1990. Wool-colonizing micro-organisms capable of utilizing wool-lipids and fatty acids as sole sources of carbon and energy. Journal of Applied Bacteriology 69 , 806–813.
Two keratinolytic fungi, Chrysosporium keratinophilum and Malbranchea anamorph of Uncinocarpus reesii , and another three wool-colonizing fungi not previously reported to be keratinolytic, Aspergillus fumigatus, A. flavus and Scopulariopsis Candida , were isolated from soil samples baited with animal wool. These fungi were tested for their ability to utilize wool-lipids as sole source of carbon and energy. The lipid contents of wool of various animals ranged between 2 and 5%. The different lipid extracts were similar in composition; they contained steryl esters, sterols, fatty acids, fatty alcohols and monoacylglycerols. The predominant acyl moiety in wool-lipids of different animals was linolenic acid (18:2). The five fungi tested grew well on an inorganic medium supplemented with total wool-lipids as sole sources of carbon and energy. Individual lipid classes fractionated by preparative thin layer chromatography and suspended into inorganic medium were able to support fungal growth as sole carbon sources. These fungi and another eight wool-colonizing strains. C. tropicum, C. zonatum, C . anamorph of Arthroderma curryei, Microsporum cams, M. distortum, Trichophyton interdigitale, Emmonsia parva and Myceliophthora vellerae could also utilize standard lipids and fatty acids (cholesterol and palmitic and linoleic acids)- Evidence for the uptake and degradation of chloesterol by C. keratmophilum is presented.  相似文献   
74.
Summary The rheological properties of yeast (Baker's yeast) suspensions in water and in water-methanol-electrolyte solutions have been investigated using a Fann V.G. concentric cylinder viscometer. The resulted rheograms could be described by the power law model for non-Newtonian fluids with the flow behaviour index n<1 indicating pseudo-plastic behaviour. This flow behaviour index was constant under all operating conditions while the consistancy index k increased exponentially with increasing wet yeast volume fraction. The addition of methanol and electrolytes had a negligible effect on the rheological properties. Changing the pH of the suspension acidic to lowered the apparent viscosities.  相似文献   
75.
76.
The aim of this study was to investigate the effective role of silymarin either alone or in combination with chlorogenic acid and/or melatonin against the toxic impact of carbon tetrachloride (CCl4) induced cardiac infarction. CCl4 (l.2 ml/kg body weight) was administered as a single dose intraperitoneally. The results revealed that the administration of silymarin alone or in combination with chlorogenic acid (CGA) and/or melatonin for 21 consecutive days, 24 h after CCl4 injection to rats, markedly ameliorated the increases in serum markers of cardiac infarction, including troponin T and creatine kinase-MB (CK-MB), as well as increases in the pro-inflammatory biomarkers, including interleukin-6 (IL-6), interferon-γ (IFN-γ) in serum and tumor necrosis factor-α (TNF-α) and C-reactive protein in cardiac tissue compared to CCl4 intoxicated rats. The used agents also successfully modulated the alteration in vascular endothelial growth factor (VEGF) in serum and the oxidative DNA damage and the increase in the apoptosis marker caspase 3 in cardiac tissue in response to CCl4 toxicity. The present biochemical results are supported by histo-pathological examination. The current results proved that treatment with silymarin in combination with CGA and melatonin was the most effective one in ameliorating the toxicity of CCl4 induced cardiac damage and this may support the use of this combination as an effective drug to treat cardiac damage induced by toxic agents.  相似文献   
77.
Secondary hyperparathyroidism and trace elements’ metabolism disturbances are common, important, and treatable complications of chronic renal failure (CRF).The relation between parathyroid hormone (PTH) and some trace elements in CRF patients on hemodialysis is still not completely elucidated. The aim of this work is to determine the serum levels of PTH and the trace elements zinc (Zn) and magnesium (Mg) in children with CRF under hemodialysis. The relation between PTH and those trace elements will be investigated. The study included 24 children (15 males and nine females) with CRF on regular hemodialysis. Also, 15 healthy age-matched children were included as control group. Serum levels of PTH, zinc, and magnesium were determined in all cases and controls. PTH and magnesium levels in patients were significantly higher than controls. Serum zinc levels were significantly lower than controls. There was a significant negative correlation between serum levels of PTH and zinc as well as an insignificant negative correlation between PTH and serum magnesium in CRF patients. Elevated PTH may play a role in the pathogenesis of hypozincemia. However, this is another negative report on the relation between PTH and serum Mg in children with CRF.  相似文献   
78.
Osteoclasts are multinucleated bone resorbing cells which form by fusion of pre-osteoclasts. Here, we investigate how nitric oxide (NO) affects osteoclastogenesis. Time lapse photomicrography, using the fluorescent NO indicator dye, 4,5-diaminofluorescein diacetate, revealed an intense NO signal in pre-osteoclasts preceding cell fusion. Osteoclastogenesis in RAW264.7 cells increased when exposed to the NO synthase inhibitor, l-NMMA (0.25 μM), for the initial 48 h. In contrast, pre-osteoclast fusion decreased when RAW264.7 cells were exposed to l-NMMA from 48 to 96 h. Both NO synthase inhibitors, l-NMMA and l-NAME, decreased osteoclast formation during this time period. The inhibitory effect of l-NMMA on osteoclast formation was abolished with increasing concentrations (25–200 ng/ml) of sRANKL suggesting signaling cross talk. NO donors increased osteoclast formation in a dose-dependent manner, with greatest stimulation at 15 μM NOC-12 (2.3 fold) and 5 μM NOC-18 (2.4 fold). Measuring nitrite (NO end product) daily from culture media of RAW264.7 cells undergoing osteoclastogenesis revealed that an increase in NO production coincided with the fusion of pre-osteoclasts (day 4). Inhibiting fusion by plating cells on polystyrene dishes pre-coated with poly-(l-lysine) decreased both osteoclast formation and NO production. To address if NO mediates fusion through the actin cytoskeleton, actin free barbed ends were measured. 0.25 μM l-NMMA decreased, while 15 μM NOC-12 and 5 μM NOC-18 increased actin free barbed ends. We hypothesize that while NO initially negatively regulates pre-osteoclast differentiation; it later facilitates the fusion of mononuclear pre-osteoclasts, possibly by up regulating actin remodeling.  相似文献   
79.
Growth and osmotic potential of calli induced from leaf- and root-derived tissues of six tepary bean lines (Phaseolus acutifolius) varying in drought resistance were assessed in vitro after polyethylene glycol-induced (10%, PEG-10,000) dehydration. Calli of resistant teparies were characterized by low initial osmotic potential (ψs) and relative growth rate (RGR) on medium lacking PEG (−0.30 MPa). However, calli of both resistant and sensitive lines were similar in dry matter percent (DM). Presence of PEG in the medium (−0.58 MPa) elevated DM in all teparies except one resistant line. Both leaf- and root-derived calli of sensitive teparies exhibited osmotic adjustment (OA) but reduced RGR that remained after rehydration in one line. We concluded that preexisting force of low cellular ψs rather than induced OA plays an important role in buffering adverse effects of dehydration and conditioning drought resistance of tepary beans. This information may aid Phaseolus breeders in screening for drought resistance among large number of accessions.  相似文献   
80.
The Drosophila ATP7 copper transporter has sequence homology to the human copper transporters ATP7A and ATP7B, which are defective in Menkes and Wilson disease, respectively. We show here that in Drosophila ATP7 is expressed by many peptidergic neurons. As C-terminal amidation of neuropeptides depends on the copper-containing enzyme PHM, it seemed likely that in the absence of ATP7 the activity of PHM might be compromised. Indeed, inhibition of ATP7 expression by RNAi led to a decrease in mature amidated neuropeptides and the appearance of C-terminally Gly-extended neuropeptides. The strength of this effect differed from one cell type to another; it was very pronounced for AKH and corazonin, but much less so for SIFamide and myosuppressin. Nevertheless, down-regulation of ATP7 specifically in the SIFamide-expressing neurons resulted in male-male courtship behavior.  相似文献   
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