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21.

Scutellum derived calli of recalcitrant indica rice variety ASD-16 are subjected to qualitative and quantitative changes using different callus induction media (CIM). The suitable media for generation of regenerating calli by evaluating the increase in size of these calli as a function of time (MeazureTM2.0 software), were recorded (till 25-days post-inoculation). After 10-days post-inoculation significant differences which ranged from 5 mm to 6.5 mm and 30% variation in calliQuery size were recorded for different CIM. Improved regeneration achieved by reducing the time on callusing media to 5-days and 10-days. Also, the insights are provided for the role of cationic and anionic strength, phenomics of somatic embryogenesis, and also browning of the calli for recalcitrant indica rice variety ASD-16. The statistical analysis of size of calli with ionic strength of cations K+, H+, NH4+, Mg2+, Ca2+ and anions PO43?, NO3?, Cl? (statistical analysis tool “The Unscramble X”) shows positive correlation. The loss of scutellum derived calli due to browning was reduced by allowing the mature seed used for generation of calli to be attached to the growing calli. The browning of the calli was monitored in different media for the pattern, and statistical evidences are provided for the important role played by ionic ratios of media constituent namely, NH4+/NO3? and SO42?/PO43? (reported here for the first time). Maximum healthy calli obtained (80%) were on CIM-2 whereas maximal browning (60%) was obtained on CIM-4 after 15-days post-inoculation. Successful regeneration is achieved for recalcitrant indica rice variety ASD-16.

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22.
One of the major challenges for scientists and engineers today is to develop technologies for the improvement of human health in both developed and developing countries. However, the need for cost‐effective, high‐performance diagnostic techniques is very crucial for providing accessible, affordable, and high‐quality healthcare devices. In this context, microfluidic‐based devices (MFDs) offer powerful platforms for automation and integration of complex tasks onto a single chip. The distinct advantage of MFDs lies in precise control of the sample quantities and flow rate of samples and reagents that enable quantification and detection of analytes with high resolution and sensitivity. With these excellent properties, microfluidics (MFs) have been used for various applications in healthcare, along with other biological and medical areas. This review focuses on the emerging demands of MFs in different fields such as biomedical diagnostics, environmental analysis, food and agriculture research, etc., in the last three or so years. It also aims to reveal new opportunities in these areas and future prospects of commercial MFDs.  相似文献   
23.
Microwave assistance was used for preparing polyethylene glycol (PEG)-Cibacron blue 3GA and Sepharose CL-4B-Cibacron blue 3GA affinity materials. The former was used as the affinity macroligand in a PEG-dextran aqueous two-phase system for purification of alcohol dehydrogenase and EcoRI. The Sepharose CL-4B-Cibacron blue 3GA was used for affinity chromatography of the above two enzymes. It was found that microwave assistance could reduce the time of PEG-dye preparation to 5 min (from 7h). Similarly, Sepharose CL-4B-Cibacron blue 3GA preparation time could be reduced to 21 min (from 3.5h). The performances of affinity macroligand PEG-dye and the affinity medium Sepharose-dye prepared by conventional methods and with microwave assistance were similar during purification of these enzymes.  相似文献   
24.
Traps exert an omnipotent influence over the performance of halide perovskite optoelectronic devices. A clear understanding of the origin and nature of the traps in halide perovskites is the key to controlling them and realizing optimal devices. Herein, the role of localized traps on the optical properties of lead bromide perovskite films is investigated. In the low‐temperature orthorhombic phase of CH3NH3PbBr3 perovskite, band‐edge carrier dynamics exhibit a power‐law decay due to the presence of structural‐disorder‐induced localized traps, which has a depth of ≈40 meV. The continuous distribution of these localized traps gives rise to a broad sub‐band‐gap emission that becomes more prominent in thicker films with a larger trap density. The presence of this emission only from the hybrid organic–inorganic perovskites points to the vital role of organic dipoles in localized trap states formation. This study explicates the nature of these localized traps as well as their nontrivial role in carrier recombination kinetics, which is of fundamental importance in perovskites optoelectronics.  相似文献   
25.
Inadequate magnesium (Mg) intake is a widespread problem, with over 50% of women of reproductive age consuming less than the Recommended Dietary Allowance (RDA). Because pregnancy increases the requirement for Mg and the beneficial effects of magnesium sulfate for preeclampsia/eclampsia and fetal neuroprotection are well described, we examined the outcomes of Mg deficiency during pregnancy. Briefly, pregnant Swiss Webster mice were fed either control or Mg-deficient diets starting on gestational day (GD) 6 through euthanasia on GD17. Mg-deficient dams had significantly reduced weight gain and higher plasma adipokines, in the absence of inflammation. Livers of Mg-deficient dams had significantly higher saturated fatty acids (SFAs) and monounsaturated fatty acids (MUFAs) and lower polyunsaturated fatty acids (PUFAs), including docosahexaenoic acid (DHA) (P < 0.0001) and arachidonic acid (AA) (P < 0.0001). Mechanistically, Mg deficiency was accompanied by enhanced desaturase and elongase mRNA expression in maternal livers along with higher circulating insulin and glucose concentrations (P < 0.05) and increased mRNA expression of Srebf1 and Chrebp, regulators of fatty acid synthesis (P < 0.05). Fetal pups exposed to Mg deficiency were growth-restricted and exhibited reduced survival. Mg-deficient fetal livers showed lower MUFAs and higher PUFAs, with lower desaturase and elongase mRNA expression than controls. In addition, DHA concentrations were lower in Mg-deficient fetal brains (P < 0.05). These results indicate that Mg deficiency during pregnancy influences both maternal and fetal fatty acid metabolism, fetal growth and fetal survival, and support better understanding maternal Mg status before and during pregnancy.  相似文献   
26.
Atherosclerosis being considered as an inflammatory disorder, the present study was undertaken to investigate the effectiveness of anti-inflammatory drugs (ibuprofen, aspirin, and celecoxib) in hypercholesterolemia. Ibuprofen is a cyclooxygenase (COX-1 and COX-2) inhibitor known to reduce the production of prostaglandins that play prominent role in inflammation. Beside the anti-inflammatory effects that make ibuprofen interesting for the treatment of condition associated with hypercholesterolemic atherosclerosis. Various other properties of ibuprofen were investigated, ibuprofen showed better reduction in total cholesterol, triglycerides, very low density lipo-protein, low density lipo-protein and atherogenic index than aspirin and celecoxib in hypercholesterolemic animals. These properties of ibuprofen may be due to inhibition of acetyl-CoA carboxylase initiating the synthesis of fatty acids. Ibuprofen significantly elevated antioxidant (super oxide dismutase; catalase) levels and reduced lipid peroxidation. Ibuprofen inhibits COX enzymes and thereby inhibits generation of free radicals during prostaglandins synthesis, which may be responsible for reduction in lipid peroxidation, super oxide dismutase levels and for high catalase levels. Interestingly, ibuprofen decreased total leukocyte count, monocyte count, erythrocyte sedimentation rate and C-reactive protein levels. From the results of present study, it can be concluded that ibuprofen (non-selective COX inhibitor) showed promising antihyperlipidemic, antiatherosclerotic, antioxidant, antiinflammatory and non-ulcerogenic activity in atherosclerotic animals as compared to aspirin (preferential COX-1 inhibitor) and celecoxib (selective COX-2 inhibitors, suggesting the inducible role of COX in atherosclerosis.  相似文献   
27.
Ecological associations are the inter-relationship between the species and their environment. Oceanographic processes like upwelling events and formation of eddies, rings, and fronts have been monitored using National Oceanic and Atmospheric Administration Advanced Very High Resolution (NOAA AVHRR) and Indian Remote Sensing Satellite-P4-Ocean Colour Monitor (IRS-OCM) data. Sea Surface Temperature (SST) and chlorophyll concentration (CC) images were derived from AVHRR and OCM, respectively. Upwelling event was monitored using AVHRR-SST by detecting the differences in surface water temperature. The formation of eddies, rings, cyclonic eddies, and anti-cyclonic eddies and their biological responses were studied using CC. Eddies and rings were found with high phytoplankton production in the form of bloom, which provide grazing ground for fishes. The anti-cyclonic eddies were found with very low CC, indicating the biological deserts in the ocean. The impacts of these processes on fish catch were studied using fishing operations data procured from Fishery Survey of India. In this paper, the occurrence of different oceanographic processes, their persistence, and relevance with catch statistics of fishery resources in the study area are discussed. The study explains the potentials of satellite remote sensing to establish the habitat linkage between oceanographic processes and fishery resources. Guest editor: V. D. Valavanis Essential Fish Habitat Mapping in the Mediterranean  相似文献   
28.
The purpose of this study was to evaluate the effect of formulation components on the in vitro skin permeation of microemulsion drug delivery system containing fluconazole (FLZ). Lauryl alcohol (LA) was screened as the oil phase of microemulsions. The pseudo-ternary phase diagrams for microemulsion regions were constructed using LA as the oil, Labrasol (Lab) as the surfactant and ethanol (EtOH) as the cosurfactant. The formulation which showed a highest permeation rate of 47.15 ± 1.12 μg cm−2 h−1 and appropriate physicochemical properties was optimized as containing 2% FLZ, 10% LA, 20% Lab/EtOH (1:1), and 68% double-distilled water (w/w). The efficiency of microemulsion formulation in the topical delivery of FLZ was dependent upon the contents of water and LA as well as Lab/EtOH mixing ratio. It was concluded that the percutaneous absorption of FLZ from microemulsions was enhanced with increasing the LA and water contents, and with decreasing the Lab/EtOH ratio in the formulation. Candida albicans was used as a model fungus to evaluate the antifungal activity of the best formula achieved, which showed the widest zone of inhibition as compared to FLZ reference. The studied microemulsion formulation showed a good stability for a period of 3 months. These results indicate that the studied microemulsion formulation might be a promising vehicle for topical delivery of FLZ.  相似文献   
29.
We present here the results of protein extraction from different ocular regions using different detergents. Extraction strategies used to determine optimal protein extraction included: pressure cycling and aqueous-organic phase extraction in combination with electrophoretic fractionation for anterior, posterior, and peripapillary sclera. Detergent extraction of proteins from freshly enucleated porcine eyes (n = 8) showed significant differences for different eye regions. Protein yield ranged from 2.3 to 50.7 mug protein/mg for different ocular tissues, with the lens yielding the most protein. ASB-14 and Triton X-100 provided the best protein yields (n = 10) for anterior and posterior sclera. The spectrophotometric measurements for ASB-14 were not consistent with SDS-PAGE densitometry. A combination of 0.5% Triton X-100, 0.5% Tween-20, and 0.1% Genapol C-100 was found optimal for extraction from sclera. Proteins from different regions of the eye are best extracted with different detergents. The pressure cycling technology provided superior extraction compared to the other methods. Additional aqueous-organic phase partitioning enables superior fractionation when compared to SDS-PAGE alone. Organic phase fractionation is compatible with MS and allowed identification of 34, 71, and 77 proteins respectively from anterior, posterior, and peripapillary sclera. The extraction strategy may affect the final outcome in protein profiling by MS or by other methods.  相似文献   
30.
In this study, Lactobacillus bulgaricus NCDC (09) and Lactobacillus fermentum TDS030603 (LBF) were evaluated for their ACE-inhibitory activity and peptides production under optimized conditions from fermented camel milk (Camelus dromedarius). Lactic cultures were evaluated for their pepX activity, proteolytic activity and ACE-inhibitory activity. 09 culture exhibited higher PepX and ACE-inhibitory activity than LBF. 2% rate of inoculation and 12 h of incubation were optimized on the basis of pepX and proteolytic activity. Purified peptides from fermented camel milk were characterized by amino acids profiling through the search in BlastP, Protein information resource (PIR) databases. ACE-inhibitory activity of different peptides from fermented camel milk were also confirmed by the database of antihypertensive peptides (AHTPDB). Fermented camel milk produced by Lactobacillus cultures could be a novel source of ACE-inhibitory peptides.  相似文献   
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