Objective:To prepare fluorouracil-loaded chitosan nanoparticle (5-Fu-CS-NP) for ophthalmologic usage and evaluate its releasing characteristics in vitro. Methods: 5-Fu-CS-NP was prepared with 5-Fu, polyacrylic acid and chitosan using dispersion method. The mean size, entrapment efficiency (EE%), drug loading (DL%) and the in vitro releasing characteristics of 5-Fu-CS-NP were investigated.Results and conclusion: The mean size of 5-Fu-CS-NP was (144.6?3.1) nm, the EE% was 84.5% and the DL% was 3.91%. 5-Fu-CS-NP had a satisfactory sustained-releasing effect and the releasing could last for 3-7 days, and the release behavior was not greatly changed within a pH value of 7.2-7.4.

Acrylonitrile ; toxicity ; Carcinogens ; toxicity ; Humans ; Mutagens ; toxicity ; Occupational Exposure

Based on the lethal rate, positive and negative mutation rate, the optimal doses of UV, HNO2, UV + AO treating S. hygroscopicus NND-52-29 were determined. The mutant strain A19 that was obtained showed the derepres-sive property to glucose and the nigericin yield of A19 could be increased by 128%. When it was subcultured combined with natural screening, its stability was rather satisfied.

Objective To establish a high performance liquid chromatographic method for determination of 6-methyl coumarin in cosmetics. Methods Samples were extracted with ethanol, On C18 column CH3CN-0.02 mol/L NaH2PO4(pH=3.5, 35∶65) was applied as mobile phase, 6-Methyl Coumarin in cosmetics was determined by photo-diode-array(PDA) detector. Results The linear range of the method was 1.0-25.0 mg/L. The lowest detected limit of 6-Methyl Coumarin in 1.0 g samples was 0.000 1%. The recovery rates were 96.6%-99.2%, and the relative standard deviation were 2.0%-4.4%. Conclusion The method was simple, rapid and accurate, which was suitable for determination of 6-methyl coumarin.

Objective To study the relationship between the invasion of pituitary adenomas and expressions of MMP-9,Ki-67 and nm23. Methods The expressions of MMP-9,Ki-67 and nm23 were examined by immunohistochemical Elivision methods in 78 cases of pituitary adenomas. Of them,40 cases were invasive pituitary adenomas and, 38 cases were noninvasive pituitary adenomas. Results The expression levels of MMP-9 and Ki-67 in the invasive pituitary adenomas were significantly higher than those in the noninvasive ones (P

China ; epidemiology ; Cross-Sectional Studies ; Female ; Health Status ; Humans ; Male ; Occupational Health

Action Potentials ; drug effects ; Animals ; Mice ; Mice, Inbred Strains ; Neurons ; drug effects ; physiology ; Plant Extracts ; pharmacology

[Objective]To introduce a method to obtain Schwann cells from newly born SD rats massively and purely by immunomagnetic heads method.[Method]SD rats that had been born within 5 to 7 days were used. Their bilateral sciatic nerves were dissected under sterile condition. Under 16?microscope the nerve fascicles and the epineurium were carefully extracted in oder to get the nerve tract without impurity cell. Then the nerve tract was cut into small particle about 1 mm3.Two enzymes (0.25% trypsinase and 0.2% collagenaseⅠ)were used to digest the particle of sciatic nerve specimens twice. After using 20% fetal bovine serum to stop the process of digestion,centrifugate(1000r/min,5 min) and DF12 culture medium was added into the precipitation.Seven days later,Schwann cells were purified with immunomagnetic heads.During the whole process,the change of Schwann cells was observed under the inverted biological microscop and vital force of Schwann cells was evaluated.The growth curve of Schwann cell was drawn with MTT.The Schwann cells was identicated under immunofluorescent test and record the purity.[Result]The cell separated from the SD rat's sciatic nerve and cultured in incubator was affirmed as Schwann cells.Immunomagnetic heads can be used to purify the Schwann cells.The 96% vigor and 98% pure Schwann cell cultures were generated and passaged after two days.[Conclusion]This method can obtain massive purified normal schwann cells to satisfy the need of tissue-engineered bioartificial nerve graft.

[Objective] To investigate the combined effects of different neurotrophin couples of NGF,bFGF,BDNF on rat spinal cord neurons.[Method]Spinal cord neurons were obtained from SD rats born within 1d,and then were seeded in culture plates.Different factors and their couples were added in each chamber while DMEM/F12 served as controls,concentration of NGF,bFGF or BDNF were 50ng/ml.Phase contrast microscope observation was done.At the 3rd and 7th day after incubation,the cells were detected by ?-tubulin3 immunofluorescence and Hoechst staining.The length of neuritis was measured,and the numbers of neuron cells and nuclears were determined.At the 1st,3rd,5th,7th and 9th day MTT method was used,and the growth curve was made according to OD results.[Result] The length of axon and positive rate in the experimental groups were superior to those in the control group(P

The main form of the postgraduate medical training in China is residency standard-ized training, while the residency training system in some European and American developed countries is relatively mature. A review is presented on the programs of residency standardized training in Europe and America, concentrating on their strength and defects and reaching the conclusion that standard-ization, high-efficiency, personalization, socialization and internationalization can be the new trends in the development of residency standardized training in China.