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1.
This study provides a method for enhancing the delivery of nucleic acid molecules to cells by encapsulating it inside the hydrogel pullulan nanoparticles. In this study, pullulan nanoparticles encapsulating pBUDLacZ plasmid has been prepared inside the aqueous droplets of w/o microemulsions. Transmission electron microscopy (TEM) image showed that the particles are spherical in shape with size of 45+/-0.80 nm diameter. Cell cytotoxicity studies as determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) assay demonstrated that cells incubated with nanoparticles remained more than 100% viable at nanoparticle concentration as high as 1000 microg/ml. From scanning electron microscope images, it was observed that the nanoparticles were internalised and the cells exhibited vacuoles in the cell body due to nanoparticle internalisation. Endocytosis of nanoparticles resulted in disruption of F-actin and beta-tubulin cytoskeleton of human fibroblasts. The efficacy of transfection in vitro on HEK293 and COS-7 cells demonstrated cell type dependence, with COS cells having a higher gene expression. The beta-gal expression in COS-7 cells by pullulan nanoparticle was comparable to commercially available Lipofectamine 2000. The results of this study are encouraging for the development of pullulan nanoparticles as an intracellular delivery system for drugs and genes.  相似文献
2.
The aim of present study was to prepare nanometer sized particles of gelatin via water-in-oil microemulsion system for drug and gene delivery applications. In this study, cross-linked gelatin nanoparticles encapsulating a fluorescent marker molecule fluorescein isothiocyanate-dextran (FITC-Dex, Mol. Wt. 19.3kDa) have been prepared, characterized and their influence on human fibroblasts has been assessed in terms of cell adhesion, cytotoxicity, light microscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and observation of cytoskeleton organisation. Gelatin nanoparticles were prepared inside the aqueous cores of sodium bis(2-ethylhexyl) sulfosuccinate (AOT)/n-hexane reverse micelles. Transmission electron microscopy image showed that the particles are spherical in shape with size of 37+/-0.84 nm diameter. The release of FITC-Dex from the nanoparticles in phosphate buffer saline (pH 7.4) is found to increase with time and about 80% of the encapsulated dye is released in 6 h. Cell adhesion studies with human fibroblasts have shown that gelatin nanoparticles do not affect the number of cells adhered to glass as compared to control cells with no particles. Standard cell viability assay demonstrated that cells incubated with gelatin nanoparticles remained more than 100% viable at concentration as high as 500 microg/ml. From SEM image, it was observed that the nanoparticles were internalised and the fibroblasts exhibited vacuoles in the cell body with cell membrane abnormalities. Endocytosis of nanoparticles was confirmed from TEM studies and it resulted in disruption of F-actin and beta-tubulin cytoskeleton. These studies show that the gelatin nanoparticles prepared by water-in-oil microemulsion systems are endocytosed by the fibroblasts without being toxic to cells even at high concentration of nanoparticles.  相似文献
3.
Streblus asper Lour is a small tree found in tropical countries, such as India, Sri Lanka, Malaysia, the Philippines and Thailand. Various parts of this plant are used in Ayurveda and other folk medicines for the treatment of different ailments such as filariasis, leprosy, toothache, diarrhea, dysentery and cancer. Research carried out using different in vitro and in vivo techniques of biological evaluation support most of these claims. This review presents the botany, chemistry, traditional uses and pharmacology of this medicinal plant.  相似文献
4.
Microbial digestion has the potential to break down complex organic compounds so that they may further degrade it to completely harmless form. The main objective of the present work is to reduce the colour and degradation of the industrial effluent containing extensively used textile dye Reactive Red 198 (RR198) by microbial method. The activated sludge of textile printing waste water treatment plant of Erode, Tamilnadu, India was used as a source of inocula for the isolation of an efficient dye-decolorizing bacterium strain. The isolated bacterial strain was able to use RR198 as sole carbon source for its growth. Gram staining and 16S rDNA gene sequence analysis have identified bacterial strain as Alcaligenes sp. AP04. The isolated strain has decolorized about 90 % of initial dye concentration of Azo dye RR198 within 24 h under aerobic condition at pH 7.0 and temperature 25 °C with 50–200 mg/L dye concentration. A soluble cytosolic enzyme, azoreductase was isolated from it and its molecular mass was found to be 60 kDa. This enzyme has NADH/NADPH-dependent activity and oxygen sensitivity. The thin layer chromatography and gas chromatography–mass spectrometry (GC–MS) analysis of dye decolorized product has confirmed the successful dye degradation by the bacterial activity. Phytotoxicity and inhibition of seed germination of Cicer arietinum and Phaseolus mungo were shown by RR198 treatment while no toxicity and seed germination inhibition was found with the dye degraded products in C. arietinum and P. mungo. Present study might offer valuable implications for the practical application of Alcaligenes sp. for the treatment of azo dyes of industrial effluents.  相似文献
5.
Quality of raisins is affected by various factors like variety, pre-treatment of grape bunches, drying conditions etc. Considering the importance of raisin colour as an important quality attribute, the present study was conducted. Grape bunches were treated with different doses of ascorbic acid and sodium metabisulfite after harvesting. Applications of ascorbic acid concentrations to grapes before pretreatment of bunch by alkaloid solution on the second day of drying reduced colour intensity. Moisture content in raisins was also reduced up to 12.35 % in T3. It was an indicator of faster drying. The concentration of 300 ppm was found effective in producing quality raisins. Less colour intensity was observed when ascorbic acid was applied on bunches placed for drying than application before dipping in alkali solution in each treatment. Minimum colour intensity (6.356) was noted in T2 followed by T3 when ascorbic acid was applied on bunches placed for drying while maximum (7.344) was noted in control. The polyphenol oxidase (PPO) activities was decreased by increasing the drying duration. Lower PPO content was noted in treated grapes than control. While, no significant differences were observed for browning and colour intensity in raisins with different doses of ascorbic acid and sodium metabisulfite. However, applications of ascorbic acid and sodium metabisulfite influenced the other parameters. The present study reveals that the application of ascorbic acid is suitable for retaining good colour of raisins with faster drying and 300 ppm ascorbic acid spray on second day of drying can be adopted.  相似文献
6.
In the present investigation, detailed oral subacute toxicity study of fipronil, a phenylpyrazole insecticide, was undertaken in male buffalo calves. In oral subacute toxicity study, fipronil was administrated to male buffalo calves at repeated oral dose of 0.5 mg kg?1 day?1 for 21 consecutive days. Fipronil produced varying degree of mild to moderate toxic signs in buffalo calves. Fipronil produced toxic signs of salivation, lachrymal discharge, dullness, depression, decreased body weight gain, alopecia and sunken eyes. All the fipronil-exposed animals recovered within 7 days after insecticidal treatment was stopped. Repeated oral administration of fipronil at the dose rate of 0.5 mg kg?1 day?1 for 21 consecutive days produced significant elevation of whole blood cholinesterase to the extent of 45.17 %. Fipronil on repeated oral administration produced significant increase in the plasma levels of lactate dehydrogenase (7.08 %), aspartate aminotransferase (43.55 %) and acid phosphatase (11.647), but no significant effect on the plasma levels of alanine aminotransferase and alkaline phosphatase in male buffalo calves. Subacute oral administration of fipronil elevated the levels of gamma-glutamyl transferase (25.53 %), total plasma proteins (20.59 %) and blood glucose (40.75 %). However, no significant alteration in the levels of blood urea nitrogen, plasma creatinine and cholesterol was seen following daily oral administration of fipronil in the buffalo calves.  相似文献
7.
Acetamiprid is popular for crop protection against piercing-sucking pests and is highly effective for flea control in cats and dogs. Repeated oral administration of acetamiprid at the dose rate of 1.5 mg kg?1 day?1 for 21 consecutive days in buffalo calves did not exhibit any significant toxic signs. It however produced significant elevation in plasma aspartate aminotransferase (14 %), alanine aminotransferase (35.98 %) and gamma glutamyl transpeptidase (30.26 %), whereas no significant effect was observed on total plasma protein, blood cholinesterase, lactate dehydrogenase, phosphatases, cholesterol, creatinine, blood urea nitrogen and blood glucose. Present investigation reveals that acetamiprid is a mild-risk insecticide in buffalo calves.  相似文献
8.
A high efficiency plant regeneration protocol has been developed for Punica granatum L. cv. Kandhari Kabuli using hypocotyl explants. Hypocotyl explants (about 0.5–1.0 cm in size) were procured from 15 to 20-day-old in vitro germinated seedlings. The highest frequency of shoot regeneration (68.21 %) along with 3.18 average number of shoots per explant was obtained via direct organogenesis from hypocotyl explants cultured on Murashige and Skoog’s medium supplemented with 2.0 mg/l 6-benzyl amino purine and 1.5 mg/l α-naphthalene acetic acid. High percentage root regeneration (85.62 %) in in vitro developed shoots was obtained on half strength Murashige and Skoog’s medium supplemented with 0.10 mg/l α-naphthalene acetic acid and 0.02 % activated charcoal. Pomegranate plantlets were able to regenerate within 6 weeks and well rooted plantlets were successfully acclimatized in plastic cups containing autoclaved peat moss. They were weaned in a growth room and finally moved to a greenhouse. This is the first report on direct organogenesis in P. granatum L. cv. Kandhari Kabuli using hypocotyl explants. This regeneration protocol will be very useful for undertaking genetic manipulation providing a value addition to pomegranate propagation in future.  相似文献
9.
In this study, surface plasmon resonance (SPR) technology was used for the sensitive detection of protective antigen (PA), an anthrax specific toxin in spiked human serum samples. A monoclonal antibody raised against Bacillus anthracis PA was immobilized on carboxymethyldextran-modified gold chip, and its interaction with PA was characterized in situ by SPR. By using kinetic evaluation software, KD (equilibrium constant) and Bmax (maximum binding capacity of analyte) were found to be 20 fM and 18.74 m°, respectively. The change in Gibb's free energy (?G= −78.04 kJ/mol) confirmed the spontaneous interaction between antigen and antibody. The assay could detect 1 pg/mL purified PA. In PA-spiked human serum samples, 10 pg/mL of PA could be detected. Presence of PA in blood samples serves as an important early diagnostic marker for B. anthracis infections. Thus, SPR test can be a sensitive assay for detection of anthrax at early stages of infection.  相似文献
10.
A 759 amino acid long sequence of polymerase PB2 [Influenza A virus {A/Mexico/47N/2009(H1N1)}] was taken to build the model of the protein which was validated by different tools of SAVS (structural analysis and verification server). The modeled protein was interacted with four different drugs available in the market viz. oseltaminivir, amantadine, zanasmivir, rimantadine (RS) and some naturally occurring compounds i.e. curcuminoids (curcumin, demethoxy curcumin, bis-demethoxy curcumin and cyclocurcumin) along with two synthetic bioconjugates of curcumin viz. dipiperoyl and disalicyloyl esters. The analysis parameters including docking score, reranking score and number of H-bonds indicate cyclocurcumin as the most favoured.  相似文献
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