Objective To investigate the biocompatibility of pure titanium (Ti) and Ti-6Al-7Nb surface treated by sanding acid etch (SLA) on rat osteoblasts. Methods Experiments were divided into four groups, Ti mechanical grinding group (S1 group), Ti sand-blasting acid group (SLA1 group), Ti-6Al-7Nb mechanical grinding group (S2 group) and Ti-6Al-7Nb sand-blasting acid group (SLA2 group). The surface topography of samples was examined by microscope. The contact angle measurement instrument was used to analyse surface hydrophily of SLA1 and SLA2 groups. The surface sediment mor?phology and phase were observed by scanning electron microscopy (SEM) and X-ray diffraction (XRD) in two groups after be?ing soaked into simulated body fluid (SBF) for 7 d,14 d and 21 d. Osteoblasts extracted from rats were seeded on titanium sheets, and the osteoblast cells on different titanium surfaces were observed by inverted microscope. MTT colorimetric meth?od was used to measure the proliferation of osteoblasts. Results Compared with S1 and S2 groups, there were more holes on sample surface of SLA1 and SLA2 groups. The sample surface was hydrophilic structure in SLA1 and SLA2 groups. The con?tact angle was smaller in SLA2 group than that of SLA1 group. The hydroxyapatite coating was firstly observed in SLA2 group at 14 d. The hydroxyapatite coating was found in samples of two groups after 21 d. The proliferative ability of osteo?blasts was stronger in SLA1 and SLA2 groups than that of S1 and S2 groups. And the proliferative ability of osteoblasts was stronger in sample surface of SLA2 group than that of SLA1 group (P<0.05). Conclusion Ti-6Al-7Nb by SLA has good biological compatibility, which is helpful to promote the combination of implant and bone tissue.

OBJECTIVE:To establish a rapid and sensitive HPLC method for simultaneous determination of plasma concentrations of 6 antidepressants.METHODS:With diprozin as internal standard,the alkalized samples were extracted by liquid-liquid extraction and separated on a Phenomenex-C18 column using acetonitrile-0.05 mol?L-1 sodium dihydrogen phosphate(pH was adjusted to 2.5 by phosphoric acid) as mobile phase at a flow rate of 1.2 mL?min-1 by a gradient elution.The column temperature was set at 40℃.Venlafaxine was detected by fluorescence detection at an Ex wavelength of 276 nm and Em wavelength of 598 nm;doxepin,paroxetine,sertraline,fluoxetine and amitriptyline were detected at an UV detection wavelength of 200 nm.RESULTS:The linear ranges of venlafaxine,doxepin,paroxetine,sertraline,fluoxetine and amitriptyline were 5～1 000 ?g?L-1,40 ～200 ?g?L-1,20～800 ?g?L-1,40～1 000 ?g?L-1 and 10～400 ?g?L-1,respectively,with correlation coefficients ≥0.990 for all.Both the intra-day RSD and inter-day RSD were less than 15%;the extraction recovery rates were greater than 60% and methodological recovery were greater than 90% for all the samples.CONCLUSION:The method is simple,economical,rapid,accurate and sensitive,and it is applicable for the clinical monitoring of plasma drug concentrations as well as the analysis and pharmacokinetic study of toxic drugs.

BACKGROUND: It is well-known that a decline in the prevalence of smoking among physicians has preceded a decline in the general population. For the purpose of finding out the reason for lower smoking rate in Korean medical doctors than that of general population whether it is due to knowledge of toxicity related to smoking perceived as health professionals or as the only leader group in society this study was investigated. We selected lawyers as a representative of other professional groups. We investigated smoking rate, habits and attitudes towards smoking in Korean lawyers and compared the smoking rate and attitudes to wards smoking in lawyers with those of medical doctors. METHODS: This study investigates smoking rate, habits and attitudes towards smoking in Korean lawyers. An anonymous self-administered postal survey was used. One-third of registered lawyers were sampled according to stratified random sampling. Among 1,401 target population, 463 (38.3%) responded. RESULTS: Among male lawyers, 38.0% were current smokers, 38.9% were ex-smokers and 23.1% were non-smokers, while 7.7% were ex-smokers and 92.3% were non-smokers among female lawyers. The direct age-adjusted smoking rate among Korean male lawyers was 42.1%. CONCLUSION: In comparison of the direct age-adjusted smoking rate among male lawyers, medical doctors and general population in Korea, the rate in lawyers was 42.1%, medical doctors 34.9%, and general population 67.6%. The smoking rate of lawyers was found to be higher than that of medical doctors, but considerably lower than that of general population. In comparison of the attitudes towards smoking between lawyers and medical doctors, the lawyers were found to have a lower level of support in questions of the knowledge about the harmful effects of smoking and smoking bans on health than medical doctors.
Anonyms and Pseudonyms ; Female ; Health Occupations ; Health Services Needs and Demand ; Humans ; Korea* ; Lawyers* ; Male ; Prevalence ; Smoke* ; Smoking*

BACKGROUND: In comparison to the decreasing smoking rate of adults, the smoking rate in adolescents and women is still increasing worldwide including Korea. Previous studies on the smoking rate of adolescents were done by questionnaires allowing bias in their response because of smoking ban among adolescents in Korea. In order to know the actual smoking rate of Korean adolescents, we performed an objective study using urine nicotine detection. METHODS: From April to July 2002, 306 boy's high school students and 325 girl's high school students in Seoul were included for this study. We obtained self-reported questionnaire from them and assessed urine nicotine level by NicCheck I Test Strip to check their actual smoking status. RESULTS: The current smoking rate of male students by self-reported questionnaire was 14.9%, 20.4%, 22.5%, respectively and that by detection of urine nicotine was 26.6%, 38.0%, 29.6%, respectively, in the 1st, 2nd and 3rd grade. The current smoking rate of female students by self-reported questionnaire was 22.6%, 23.9%, respectively and that by detection of urine nicotine was 46.6%, 35.4%, respectively in the 2nd and 3rd grade. The Kappa index of the questionnaire results was 0.27, 0.46, 0.75, respectively in the 1st, 2nd and 3rd grade male students and 0.33, 0.44, respectively in the 2nd and 3rd grade female students respectively. CONCLUSION: The smoking rate of students by detection of urine nicotine was higher than that of the self-reported questionnaire results. The validity of the questionnaire results was more accurate in males than females, and higher grade than lower grade. The self-reported questionnaire was an insufficient tool for evaluation of adolescents' smoking status, especially in female students and lower grade students.
Adolescent ; Adult ; Bias (Epidemiology) ; Female ; Humans ; Korea ; Male ; Nicotine* ; Seoul ; Smoke* ; Smoking* ; Surveys and Questionnaires