OBJECTIVE:To establish a method for simultaneous determination of residual methylparaben,ethylparaben,nipa-sol and benzalkonium chloride in marketed eye drops. METHODS:HPLC method was adopted. The determination was performed on Hypersil GOLD C18 column with mobile phase consisted of 0.005 mol/L ammonium acetate(10 mL triehtylamine in 1 L solu-tion,pH adjusted to 5.0±0.5 with glacial acetic acid)-acetonitrile(45:55,V/V)at the flow rate of 1.0 mL/min. The detection wave-length was 262 nm(methylparaben,ethylparaben,nipasol)and 214 nm(benzalkonium chloride),respectively. The column tem-perature was 30 ℃ and sample size was 20 μL. RESULTS:The linear range were 1.2350-15.4380 μg/mL for methylparaben(r=0.9999),1.3170-16.3836 μ g/mL for ethylparaben (r=0.9997),1.2072-15.0894 μ g/mL for nipasol (r=0.9996) and 17.776-222.0 μg/mL for benzalkonium chloride(r=0.9999),respectively. Limits of quantitation were 2.0,2.0,2.0,1.11 μg,re-spectively;limits of determination were 0.375,0.375,0.375,0.333 μg,respectively. RSDs of precision,stability and reproducibili-ty tests were all lower than 2.0%. The average recoveries were 98.14%-102.48%(RSD=1.6%,n=9),98.79%-102.42%(RSD=1.3%,n=9),98.19%-102.49%(RSD=1.5%,n=9)and 98.76%-100.53%(RSD=0.6%,n=9),respectively. CONCLUSIONS:The method is accurate,reproducible,simple and suitable for the determination of residual methylparaben,ethylparaben,nipasol and benzalkonium chloride in marketed eye drops.

BACKGROUND: Recombinant human bone morphogenetic protein-2 (rhBMP-2) has been widely used on clinic; however, there are still few reports addressing rhBMP-2-induced osteogenesis in intervertebral disc.OBJECTIVE: To verify the effect of rhBMP-2 to induce interbody fusion in rabbits.DESIGN, TIME AND SETTING: Randomized controlled animal study and multi-level evaluation, which was performed in Affiliated Hospital of Medical College of Qingdao University from February to July 2007.MATERIALS: 24 adult New-Zealand rabbits weighing 3.5-4.5 kg were used to expose L4-5 and L5-6 intervertebral disc; rhBMP-2 (1 mg/ampoule, purity≥95%) was provided by Beijing Bailingke Biological Products Co., Ltd.METHODS: 24 rabbits were randomly divided into experimental group and control group with 12 rabbits for each. In the experimental group, saline (20 μL, containing 200 μg rhBMP-2) was injected into nucleus pulposus of L4-5 intervertebral disc; equivalent saline was inserted into nucleus pulposus of L5-6 intervertebral disc as controls. Rabbits in the control group were injected with saline (20 μL) into nucleus pulposus of L4-5 intervertebral disc.MAIN OUTCOME MEASURES: Morphological changes of injected segments were observed by hand-feeling check together with histological and imaging tests at 10, 30, 60, and 90 days postoperatively.RESULTS: 24 rabbits were included in the final analysis. ①In the experimental group, the motion range of L4-5 segment was not limited at 10 days postoperatively, and lightly limited at 30 days, but severely limited at 60 days postoperatively; L4-5 segment was fixed tightly at 90 days postoperatively. Moreover, motion range of L5-6,segment and articular motion range in the control group were not changed remarkably. ② L4-5 interbedy space was narrowed at 10 days or even disappeared at 90 days postoperatively, and then osteogenesis fusion was formed. Transmittance of intervertebral space in the L5-6 segment and in the control group was not changed obviously. ③ Nucleus pulposus was gradually shrunk at 10 days postoperatively; partial cartilage endplate transformed into mature woven bone, and collagen fiber structure of annulus fibrosus gradually disappeared at 90 days postoperatively. A lot of mesenchymal cells were aggregated surrounding annulus fibrosus at 10 and 30 days postoperatively. Moreover, mature woven bone was formed in annulus fibrosus near to cartilage endplate at 90 days postoperatively. However, histological and morphological changes were not found in the control group at those four time points.CONCLUSION: rhBMP-2 can induce intervertebral disc osteogenesis so as to achieve interbody fusion.

Objective: To analyze the current situation and needs of primary and secondary school health clinic services, and to provide a reference for strengthening school health service in China. Methods: Investigation provinces were selected according to China s three major economic zones, 1 or 2 survey centers were selected from each province, 16 provinces and 26 survey centers were selected. In each survey centers, six schools from primary and secondary schools, junior high schools and high schools in urban and rural areas were randomly selected as research sites. Each research site randomly selected 10 students in each grade(grade three, four, five from primary schools) to fill in the questionnaire anonymously. A total of 4 661 valid questionnaires were collected. Results: Among the services provided by the school clinics to students, "trauma treatment" "consulting health problems" "physical examination" accounted for 49.4%, 40.5% and 39.0% respectively. Within the past one year, 45.1% students went to the school clinic for consultation or consultation 1-3 times, 6.4% for 4-5 times, and 3.7% for 6 times or more. When students were sick in school, 65.8%(primary school), 64.0%(junior high school), and 54.4%(high school) of them selected to go to the school clinic. When suddenly suffered trauma in school, 78.2%(primary school), 73.2%(junior high school) and 69.6%(high school) of the students went to the school clinic. Conclusion Primary and middle school students have a great demand for school health services, and it is necessary to continue to strengthen the construction of primary and secondary school health clinics.