[Objective] To observe the effect of stanozolol on proliferation and differentiation of cultured growth plate chondrocytes in vitro.[Methods] At 3 week of age,Sprague–Dawley rats received 2.5 mg/kg in slow-released GnRHa (triptorelin) which was repeated every 2 weeks for 2 times,at 7-week old.The tibial growth plate cartilage were aseptically dissected and tripsin and EDTA digested for 0.5 h,then collagenase digested for 3 h at 37 ℃.Chondrocytes were cultured in DMEM:F12 medium for 48 h,the cells were starved for 24 h in serum-free DMEM:F12 medium before stanozolol treatment.In dose-effect groups,chondrocytes were incubated in serum-free media in various concentrations of stanozolol for 48 h.In time-course groups,chondrocytes were incubated in serum-free media in various times of stanozolol (10-8 mol/L).immunohistochemical staining of collagen Ⅱ,Ⅹ,PCNA,and MTT were conducted.[Results] The results of MTT,PCNA,and typeⅡcollagen synthesization demonstrated stanozolol enhanced the proliferation of the chondrocytes,time-course studies had shown that the proliferation were maximally stimulated by stanozolol after 2 or 3 days of incubation and decreased again after longer periods of incubation.Stanozolol stimulated the proliferation of the chondrocytes dose-dependently at 10-11 mol/L and 10-8 mol/L,maximally stimulatory concentrations of Stanozolol was 10-9 ～ 10-8 mol/L,and decreased again after higher concentration of stanozolol.Stanozolol did not stimulated type X collagen synthesization from 10-11 mol/L ～ 10-8 mol/L,but experiments showed that type X collagen was already stimulated after incubation in Stanozolol (10-7 ～ 10-5 mol/L).Time-course studies had shown those typeⅩcollagen synthesizations were stimulated by stanozolol after 4 ～ 5 days of incubation.[Conclusion] Stanozolol enhances the proliferation of chondrocytes of pubertal female rat treated with GnRHa in vitro (time-course- dependent and concentration -dependent).

Objective: To investigate the health of deciduous teeth and the effect of deciduous teeth caries on the nutritional status of Tibetan children in kindergartens in Zhag-yab of Tibet, so as to provide a reference for the prevention and treatment of dental caries in local children. Methods: A cross sectional survey was conducted among all Tibetan children aged 3 to 7 years in kindergartens from 13 districts in Zhag yab of Tibet, a total of 1 263 eligible children were included. Oral examination, height, weight measurement and hemoglobin test were performed. The health status of children was evaluated according to WHO diagnostic criteria of dental caries rate, average of decayed missing filled tooth(DMFT), malnutrition and anemia, and the correlation between deciduous teeth caries and nutritional status of children were analyzed. Results: The overall deciduous teeth caries prevalence rate of Tibetan children in Zhag yab kindergarten was 62.6%, and the mean dmft was (4.0±4.6). Aged 3, 4, 5, 6, 7-year-old children s deciduous teeth caries rate were 31.1%, 55.3%, 63.8%, 70.9%, 76.6%, respectively, mean dmft were (1.1±2.0) (2.9±3.4) ( 3.5± 3.3) (5.4±5.4) (5.9±6.6) respectively. The prevalence of deciduous teeth caries and mean dmft increased with age, and the differences among age groups were statistically significant ( χ 2/F=72.17, 33.47, P <0.05). The overall detection rate of malnutrition( 25.4% ), stunting(12.3%), underweight(12.6%), wasting(10.9%) and anemia(29.6%) in caries children were higher than those in children without caries(19.5%, 8.1%, 6.1%, 6.6%, 15.5%), the differences were statistically significant ( χ 2=5.81, 5.49, 13.61 , 6.52, 32.02, P <0.05). Caries children s overweight rate (3.7%) was higher than that of children without caries (3.4%), obesity rate ( 1.3% ) was lower than that of children without caries(1.9%), there was no statistically significant difference ( χ 2=0.07, 0.82, P >0.05). Conclusion The problem of deciduous teeth caries in kindergartens in Zhag yab is serious, and it is closely related to the occurrence of malnutrition and anemia. The prevention and intervention of dental caries in local children should be strengthened.