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101.
102.
The construction of SnO2 nanoparticles (NPs), specifically Te-doped SnO2 NPs, using a simple and economical co-precipitation technique has been thoroughly described in this work. NH3 served as the reducing agent in this procedure, whilst polyethylene glycol served as the capping agent. The primary goals of our work were to investigate the physicochemical properties of the synthesized SnO2 NPs and assess their potential use as antibacterial agents and photocatalysts. Scanning electron microscopy–energy dispersive X-ray, ultraviolet light, Fourier transform infrared spectroscopy, X-ray diffraction (XRD), and other analytical techniques were used to thoroughly analyze the NPs. Based on the full width at half maximum of the most noticeable peaks in the XRD spectrum, the Debye–Scherrer equation was used to calculate the crystallite sizes, which indicated the presence of a single tetragonal SnO2 phase. Particularly noteworthy was the exceptional photocatalytic activity of graphene-assisted Te-doped SnO2 NPs, achieving an impressive decomposition efficiency of up to 98% in the photo-oxidation of methylene blue. Furthermore, our investigation delved into the antibacterial attributes of the synthesized SnO2 NPs against Escherichia coli and Staphylococcus aureus, demonstrating inhibitory effects on both bacteria strains. This suggests potential applications for these NPs in various environmental and medical contexts.  相似文献   
103.
Fischer indole synthesis of indole by using phenyl-hydrazine and acetaldehyde resulted 1H-Indole while phenyl-hydrazine reacted with malonaldehyde gives 1H-Indole-3-carbaldehyde. Also Vilsmeier-Haack formylation of 1H-Indole gives 1H-Indole-3-carbaldehyde. 1H-Indole-3-carbaldehyde were oxidized to form 1H-Indole-3-carboxylic acid. 1H-Indole reacted with excess of BuLi at −78 °C using dry ice also gives 1H-Indole-3-carboxylic acid. Obtained 1H-Indole-3-carboxylic acid was converted to ester and ester in to acid hydrazide. Finally 1H-Indole-3-carboxylic acid hydrazide reacted with substituted carboxylic acid gives microbial active indole substituted oxadiazoles. Synthesized compounds 9a – j showing promising in vitro anti microbial activities against S. aureus bacteria compared with Streptomycin. Compound 9a , 9f and 9g showing activities against E. coli compared with standards. Compound 9a and 9f are found potent active against B. subtilis compared with reference standard while compound 9a , 9c and 9j active against S. typhi.  相似文献   
104.
Pseudomonas fluorescens Pt14 is a non-pathogenic and acidophilic bacterium isolated from acidic soil (pH 4.65). Genome sequencing of strain Pt14 was performed using Single Molecule Real Time (SMRT) sequencing to get insights into unique existence of this strain in acidic environment. Complete genome sequence of this strain revealed a chromosome of 5,841,722 bp having 5354 CDSs and 88 RNAs. Phylogenomic reconstruction based on 16S rRNA gene, Average Nucleotide Identity (ANI) values and marker proteins revealed that strain Pt14 shared a common clade with P. fluorescens strain A506 and strain SS101. ANI value of strain Pt14 in relation to strain A506 was found 99.23% demonstrating a very close sub-species association at genome level. Further, orthology determination among these three phylogenetic neighbors revealed 4726 core proteins. Functional analysis elucidated significantly higher abundance of sulphur metabolism (>1×) which could be one of the reasons for the survival of strain Pt14 under acidic conditions (pH 4.65). Acidophilic bacteria have capability to oxidize sulphur into sulphuric acid which in turn can make the soil acidic and genome-wide analysis of P. fluorescens Pt14 demonstrated that this strain contributes towards making the soil acidic.  相似文献   
105.
Disposal of industrial wastewater is a current issue of urbanization. However, this problem can be sorted out by using wastewater as an alternate source of irrigation after the addition of some amendment. In this way, the problem of disposal of wastewater not only will be resolved but also scarcity of irrigation water can be kept off in the future. The current research study was performed to evaluate the influence of different concentrations of wastewater along with canal water for enhancing growth and yield of field mustard. Plants were irrigated with different mixtures of canal water and wastewater (75:25, 50:50, 25:75, and 00:100) in addition to canal water as control. The results revealed that application of 50:50% waste and canal water improved plant height, the number of pods plant?1, pod length, root length, root dry weight, shoot dry weight, 100 grain weight, grain and biomass yield plant?1, and nitrogen, phosphorus, and potassium concentration in grain and straw up to 16%, 15%, 17%, 29%, 15%, 56%, 25%, 41%, 35%, 20%, 52%, 45%, 20%, 44%, and 42%, respectively, over positive control treatment. While, nutrient uptakes and agronomic efficiency of fertilizers also improved by the application of 50:50% canal and wastewater compared to positive control treatment. Furthermore, the concentration of heavy metals, predominantly Cr, Cu, Cd, and Pb, was reduced in grains by application of 50% canal water and 50% wastewater. The outcomes suggest that wastewater utilization along with canal water mixing might be an effective approach for enhancing growth and yield of field mustard.  相似文献   
106.
Hsp90 is an ATP dependent molecular chaperone protein which integrates multiple oncogenic pathways. As such, Hsp90 inhibition is a promising anti-cancer strategy. Several inhibitors that act on Hsp90 by binding to its N-terminal ATP pocket have entered clinical evaluation. Robust pre-clinical data suggested anti-tumor activity in multiple cancer types. Clinically, encouraging results have been demonstrated in melanoma, acute myeloid leukemia, castrate refractory prostate cancer, non-small cell lung carcinoma and multiple myeloma. In breast cancer, proof-of-concept was demonstrated by first generation Hsp90 inhibitors in combination with trastuzumab mainly in human epidermal growth factor receptor 2 (HER2)+metastatic breast cancer. There are a multitude of second generation Hsp90 inhibitors currently under investigation. To date, however, there is no FDA approved Hsp90 inhibitor nor standardized assay to ascertain Hsp90 inhibition. This review summarizes the current status of both first and second generation Hsp90 inhibitors based on their chemical classification and stage of clinical development. It also discusses the pharmacodynamic assays currently implemented in clinic as well as other novel strategies aimed at enhancing the effectiveness of Hsp90 inhibitors. Ultimately, these efforts will aid in maximizing the full potential of this class of agents. This article is part of a Special Issue entitled: Heat Shock Protein 90 (HSP90).  相似文献   
107.
In the present work, QSAR models for predicting the activities of ursolic acid analogs against human lung (A-549) and CNS (SF-295) cancer cell lines were developed by a forward stepwise multiple linear regression method using a leave-one-out approach. The regression coefficient (r(2)) and the cross-validation regression coefficient (rCV(2)) of the QSAR model for cytotoxic activity against the human lung cancer cell line (A-549) were 0.85 and 0.80, respectively. The QSAR study indicated that the LUMO energy, ring count, and solvent-accessible surface area were strongly correlated with anticancer activity. Similarly, the QSAR model for cytotoxic activity against the human CNS cancer cell line (SF-295) also showed a high correlation (r(2) = 0.99 and rCV(2) = 0.96), and indicated that dipole vector and solvent-accessible surface area were strongly correlated with activity. Ursolic acid analogs that were predicted to be active against these cancer cell lines by the QSAR models were semisynthesized and characterized on the basis of their (1)H and (13)C NMR spectroscopic data, and were then tested in vitro against the human lung (A-549) and CNS (SF-295) cancer cell lines. The experimental results obtained agreed well with the predicted values.  相似文献   
108.
109.
Structure–activity relationship studies were carried out for lead generation following structure-guided design approach from an isocytosine scaffold identified earlier for xanthine oxidase inhibition. A 470-fold improvement in in vitro IC50 was obtained in the process. Five most potent compounds with nanomolar IC50 values were selected for pharmacokinetics and in vivo experiments. The best compound showed good in vivo activity when administered intraperitoneally but was not active by oral route. The results suggest that improvement in oral exposure could improve the in vivo efficacy of this series.  相似文献   
110.
Cr(VI) is a toxic environmental pollutant. To determine the potential role of microbes towards chromate bioremediation, two bacterial strains, E1 and E4, that could tolerate Cr(VI) at levels up to 2250 μg ml?1 were isolated from the soil of a tannery. They were identified as Exiguobacterium sp. To estimate the removal of Cr(VI) using immobilized bacterial cells, 2% sodium alginate and 2.5% agar were used as immobilizing matrices. In the case of sodium alginate, 89% and 93% of Cr(VI) removal by E1 and E4, respectively, were observed. When agar beads were used as an immobilizing matrix, removal was recorded as 39% and 48% for E1 and E4, respectively. Removal of Cr(VI) was also estimated in sterile and nonsterile tannery effluent. More Cr(VI) removal was noted in the nonsterile effluent than in the sterile effluent. The maximum uptake of Cr(VI) of bound cells of E1 and E4 was found to be 17.54 and 20.04 μg ml?1, respectively. Fourier transform infrared (FTIR) spectra of cells of E4 with Cr(VI), without Cr(VI), and immobilized cells depicted several absorption peaks, mainly for P?OH group, C?H bending, C?O bond, and amide II groups, reflecting the complex nature of the bacterial cells and the contribution of these functional groups to the Cr(VI) binding process.  相似文献   
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