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排序方式: 共有238条查询结果,搜索用时 203 毫秒
11.
The following study was done to assess the glucose utilizing efficiency of Indoloquinoxaline derivative incorporated keratin nanoparticles (NPs) in 3T3-L1 adipocytes. Indoloquinoxaline derivative had wide range of biological activities including antidiabetic activity. In this view, Indoloquinoxaline moiety containing N, N-dimethyl (3-fluoro-6H-indolo [3,2-b] quinoxalin-6-yl) methanamine compound was designed and synthesized, and further it is incorporated into keratin nanoparticles. The formulated NPs, drug entrapment efficiency, releasing capacity, stability, and physicochemical properties were characterized by various spectral analyzer and obtained results of characterizations were confirmed the properties of NPs. The analysis of mechanism underlying the glucose utilization of NPs was examined through molecular docking with identified target, and observed in silico study reports shown strong interaction of NPs in the binding pockets of AMPK and PTP1B. Based on the in silico screening, the formulated NPs was performed for in vitro cellular viability and glucose uptake studies on 3T3-L1 adipocytes. Interestingly, 40 μg of NPs displayed 78.2 ± 2.76% cellular viability, and no cell death was observed at lower concentrations. Further, the concentration dependent glucose utilization was observed at different concentrations of NPs in 3T3-L1 adipocytes. The results of NPs (40 μg) on glucose utilization have revealed eminent result 58.56 ± 4.54% compared to that of Metformin (10 μM) and Insulin (10 μM). The identified results clearly indicated that Indoloquinoxaline derivative incorporated keratin NPs significantly increased glucose utilization efficiency and protect the cells against the insulin resistance.  相似文献   
12.
Bacopa monnieri (Linn.) Wettst. commonly known as waterhyssop, Brahmi plant, traditionally used for memory enhancement, nerve tonic, epilepsy, central nervous system (CNS), antidepressant, anxiety, blood pressure and antioxidant activities. Due to pharmaceutical demands its lost natural habitat. At this juncture we describe a resourceful protocol for micropropagation of water hyssop plant. Surface sterilized leaf and nodal explants were inoculated on basal MS semi-solid medium added with PGRs; auxins, cytokinins. Highest calli formation from leaf explants was obtained on NAA (2.5 mg−1) and showed (94.22%) accompanied via 2,4-D showed (2.5 mg−1; 82.43%), maximum calli formation in nodal explants was obtained on 2,4-D showed (2.5 mg−1; 71.14%) followed by NAA (2.5 mg−1) showed (62.15%), in internodes explants uppermost calli formation was obtained from 2,4-D showed (2.5 mg−1; 65.21%) followed by NAA (2.5 mg−1) showed (52.14%). The maximum somatic embryogenic callus, calli induction and formation (84%) was observed on 2,4-D + KIN (2.0 + 1.5 mg−1) amended solid medium. Uppermost shoot formation was observed in combination of IAA + BAP (1.0 + 1.0 mg−1) showed (78.54%) shoot formation followed by IBA (2.0 mg−1) alone showed (75.37%). The maximum shoot elongation was noticed from NAA + BAP (3.0 + 3.0 mg−1) with 21.21 cm followed by NAA (2.0 mg−1) showed (15.22 cm) although, chief root formation was obtained from IBA (2.0 mg−1) with 83.75% root formation along higher number of roots (47.43%) per shoot. Followed by IAA (2.0 mg−1) showed root induction (73.43%) and no of roots (38.54%) per shoot. In hardening under pot condition plants survivability (100%) was observed under glass house conditions, the present in vitro PTC techniques is extremely significant to gratifying its natural conservation.  相似文献   
13.
Alzheimer's disease is a progressive neurodegenerative illness accounting for approximately 50% of all types of dementia in elderly people. The only symptomatic treatment proven effective to date is the use of cholinesterase inhibitors to augment surviving cholinergic activity. The purpose of this study is to investigate cholinesterase inhibitory activity of mangroves as an alternative medicine for the treatment of Alzheimer's disease. About nine mangrove plants, which were used as folk medicine in tropical countries, were collected from Parangipettai, Vellar estuary, Tamilnadu, India. Nile Tilapia muscle homogenate was used as source of enzyme. Inhibitory effect of methanolic leaf extract was assessed under in vitro condition by incubating various concentration of the extract with total cholinesterase and butyryl cholinesterase and assessing their residual activities by Ellman's colorimetric method. The results showed that of the nine plants screened Rhizophora lamarckii, Suaeda monica, Avicennia officinalis and Sesuvium portulacastrum showed 50% inhibitory activity to both TChE and BChE at concentrations less than 2 mg/mL when compared to other plant extracts, which was comparable to the standard drug Donepezil. Phytochemical analysis showed the presence of alkaloids in high concentration which might be correlated to its cholinesterase inhibitory activity.  相似文献   
14.
15.
Quinolone resistance‐determining region is known to be the druggability site of the target protein that undergoes frequent mutation and thus renders quinolone resistance. In the present study, ligands were tested for their inhibitory activity against DNA gyrase of Streptococcus pyogenes involved in DNA replication. In silico mutational analysis on modelled gyrase A revealed that GLU85 had the most possible interactions with all the ligands used for the study. The amino acid residue GLU85 had also been predicted with an essential role of maintaining the three‐dimensional structure of the protein. When introduced with a mutation (GLU 85 LYS) on this particular residue, it had readily denatured the whole α‐helix (from 80 to 90 amino acids). This was confirmed through the molecular dynamics simulation and revealed that this single mutation can cause many functional and structural changes. Furthermore, LYS85 mutation has altered the original secondary structure of the protein, which in turn led to the steric hindrance during the ligand–receptor interaction. The results based on the G‐score revealed that ligands have reduced interaction with the mutant protein. The semisynthetic fluoroquinolone 6d, which is an exception, forms a strong interaction with the mutant protein and was experimentally verified using the antimicrobial test. Hence, the present study unravels the fact that mutation at the drug binding site is the major cause for different level of resistance by the S. pyogenes when exposed against the varying concentrations of the fluoroquinolones. Furthermore, a comparative assessment of quinolone derivative with the older generation fluoroquinolones will be of great impact for S. pyogenes–related infections. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
16.
DNA amplification fingerprinting (DAF) of 17 cyanobacterial isolates belonging to symbiotic and free-living forms of 6 different genera was done. The dendrogram analysis of 17 cyanobacterial cultures revealed three major clusters. All Westiellopsis cultures formed the first major cluster and their nucleotide relatedness ranged between 71-93%. In the second major cluster, the symbiotic cyanobacterium Anabaena sp dominated and all Anabaena cultures showed 60-75% similarity with each other. Nostoc muscorum is related to Anabaena variabilis by 85% and formed the third major cluster. The dendrogram analysis of cyanobacterial isolates clearly revealed that free-living cyanobacterial cultures were closely related with each other and were diverse from the symbiotic forms.  相似文献   
17.
Isolation of cyanobacteria was attempted from herbicide applied rice soils. The predominant genera were Westiellopsis followed by Anabaena, Nostoc and Oscillatoria. The herbicide tolerance was further tested by growing the cyanobacterial cultures in BG-11 medium supplemented with varying concentrations of the commonly used rice herbicide, viz butachlor under in vitro condition. The chlorophyll-a, phycobiliproteins and ammonia excretion were assessed at periodic intervals. Westiellopsis showed the maximum tolerance followed by Anabaena, Nostoc and Oscillatoria.  相似文献   
18.
    
To study effects of altitude, monthly sampling was undertaken from June 1993 to May 1996 in the upper Kodayar reservoir (1312 m ASL), the lower Kodayar (92 m ASL) and Azhakia Pandiapuram (plain) (Tamilnadu, India). Temperature decreased with elevation at a rate of 1 °C per 240 m; the thermal range also decreased with increasing altitude. The number of days and quantity of precipitation decreased from 161 days and 366 cm yr-1 in the upper Kodayar to 92 days and 127 cm yr-1 at the Azhakia Pandiapuram (APP). Transparency decreased from 1.5 m at the upper Kodayar to about 0.5 m at the APP. Dissolved oxygen increased with decreasing altitude but remained high (>7 mg l-1) in all the three systems. Throughout the investigation, the upper Kodayar reservoir (<6.8) and lower Kodayar lake (<7.0) remained acidic, while the APP was always alkaline. Trends for CO2 and alkalinity of the three Kodayar systems were parallel to those for pH. Though widely oscillating across calendar months, nitrate averaged c. 30 g l-1, while phosphate increased from 8 g l-1 in the upper Kodayar to 18 g l-1 at the APP. Wide oscillations in nitrate suggest that it may be limiting productivity more than phosphorus. Chlorophyll-a values were c. 1.9 g l-1 throughout the year in the upper Kodayar, and between 10 and 20 g l-1 in the other two ecosystems; values peaked during the dry season, from January to April. Chlorophyll-a concentrations correlated positively with productivity; every g increase in chlorophyll-a caused 0.15 gC m-3 d-1 more production. The pristine water of the fragile upper Kodayar had the lowest productivity, and poorest diversity and population density. The species richness was assessed using organisms larger than 75 m filtered by a plankton net. There were five species (Staurastrum spp., Staurodesmus spp., Botryococcus) of phytoplankton, and three species of cladocerans and five species of copepods; population density averaged to 159 l-1 for phytoplankton, 0.3 l-1 for zooplankton. The lower Kodayar proved to be the richest for species diversity; there were 14 species of phytoplankton and six species of cladocerans and six species of copepods. Population density averaged to 203 l-1 for phytoplankton and 0.44 l-1 for zooplankton. The APP displayed moderate species richness; there were seven species of phytoplankton and six species of cladocerans, eight species of copepods and three species of rotifer; but the population density was comparatively higher than the upper and lower Kodayar; it averaged 412 l-1 for phytoplankton and 5.9 l-1 for zooplankton. These values fell within the range of values reported for other tropical and temperate lakes. Staurastrum, Ceriodaphnia cornuta, Tropocyclops, Thermocyclops and Mesocyclops sp. were present in all the aquatic systems and tolerated wide range pH between 6.5 and 8.0. APP was the most productive (4.4 gC m-3 d-1). Productivity holds positive correlation with pH and temperature; for every 1 °C increase in temperature it increased by 0.39 gC m-3 d-1 in these aquatic systems.  相似文献   
19.
The aim of the work is to investigate the effect of marine bacterial culture supernatants on biofilm formation of Vibrio spp., a major menace in aquaculture industries. Vibrio spp. biofilm cause life-threatening infections in humans and animals. Forty-three marine bacterial culture supernatants were screened against the hydrophobicity index, initial attachment and biofilm formation in Vibrio spp. Twelve culture supernatants showed antibiofilm activity. The bacterial culture supernatants S8-07 (Bacillus pumilus) and S6-01 (B. indicus) inhibited the initial attachment, biofilm formation and dispersed the mature biofilm at 5% v/v concentration without inhibiting the growth. Analysis by light microscopy and confocal laser scanning microscopy showed that the architecture of the biofilm was destroyed by bacterial supernatants when compared to the control. The bacterial supernatants also reduce the surface hydrophobicity of Vibrio spp. which is one of the important requirements for biofilm formation. Further characterization of antibiofilm activity in S8-07 culture supernatant confirmed that it is an enzymatic activity and the size is more than 10 kDa and in S6-01, it is a heat-stable, non-protein compound. Furthermore, both the supernatants failed to show any biosurfactant activity. The culture supernatants of S8-07 and S6-01 with promising antibiofilm property have potential for application in medicine and marine aquaculture.  相似文献   
20.
A facultative anaerobic species Serratia marcescens ACE2 isolated from the corrosion products of a diesel-transporting pipeline in North West India was identified by 16S rDNA sequence analysis. The role of Serratia marcesens ACE2 on biodegradation of commercial corrosion inhibitor (CCI) and its influence on the corrosion of API 5LX steel has been enlightened. The degrading strain ACE2 is involved in the process of corrosion of steel API 5LX and also utilizes the inhibitor as organic source. The quantitative biodegradation efficiency of corrosion inhibitor was 58%, which was calculated by gas chromatography mass spectrum analysis. The effect of CCI on the growth of bacteria and its corrosion inhibition efficiency were investigated. Additionally, the role of this bacterium in corrosion of steel has been investigated by powder X-ray diffractometer (XRD) and scanning electron microscope studies. The presence of high-intensity ferric oxides and manganese oxides noticed from the XRD indicates that ACE2 enhances the corrosion process in presence of inhibitor as a carbon source. This basic study will be useful for the development of new approaches for the detection, monitoring and control of microbial corrosion in petroleum product pipelines.  相似文献   
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