Objective To understand the preventive medicine students' education demand and effectiveness evaluation to train handling skills of public health critical incidents, to analyze the education problems, and to look for countermeasures to meet the demand for the talents. Methods The investigation was conducted in 105 students of preventive medicine major from two universities whose questionnaire included the handling public health critical incidents knowledge, public health critical incidents knowledge demand, education evaluation and so on. Results All the students believed that it was essential to handle knowledge of public health critical incidents. 78.1 percent of students believed that it was important to master knowledge of public health critical incidents for improving their competitiveness. 84.8 percent of students thought it inadequate to have textbook knowledge only. 75.2 percent of students held the professional training should be strengthened. Conclusions The current education programs are unable to meet the students' demand for knowledge on handling public health critical incidents and lack the relevant contents. The education organizations are supposed to reform preventive medicine education model, to increase the content of courses, and to prolong training duration. The pertinent knowledge of public health critical incidents should also be integrated into the training programs for students.

AlM: To compare the anterior segment measurements derived from optical low coherence reflectometer ( Lenstar LS900 ) and combined Scheimpflug - Placido disk topographer ( Sirius) .
METHODS: ln this study, we enrolled healthy myopic subjects 54 ( 87 eyes ) . The central corneal thickness (CCT), anterior chamber depth (ACD), flat keratometry ( FK) readings , steep keratometry ( SK ) readings and white to white ( WTW ) were measured by LS900 and Sirius. Evaluation and analysis were performed using paired t tests, the Pearson correlation, and Bland-Altman analyses.
RESULTS: The CCT and ACD measurements were significantly lower whereas FK, SK and WTW measurements were higher with LS900 (P<0. 001). Mean differences were -6. 11 ± 6. 32μm,-0. 09 ± 0. 07mm, 0. 18 ± 0. 25D, 0. 21 ± 0. 36D and 0. 25 ± 0. 39mm with statistical significant (P<0. 01). Pearson correlation analysis showed high correlation between the 2 devices for all measurements (P<0. 001). On Bland-Altman analysis, 95% limits of agreement for all measurements were 6. 26 to -18. 49μm; 0. 04 to 0. 22mm; 0. 68 to 0. 32D; 0. 92 to 0. 50D and 1. 00 to 0. 5mm.
CONCLUSlON: Anterior segment parameters evaluated with LS900 and Sirius systemare correlated well and achieve good agreement. However, there are significantly statistical differences which may be caused by the different measurement modes, so they may not be interchangeable use under certain clinical circumstances.

Objective To explore the risk factors contributing to wound complications following operative fixation for fractured calcanea.Methods Fitly-six patients with 61 fractured calcanea who had been treated with operative fixation from March 2000 to March 2003 were enrolled in investigation.General information of the pa- tients,ages,injury causes,classification of fracture,fall heights,smoking,delayed operation time,operation time and tourniquet time were documented preoperatively and postoperatively to be analyzed statistically.Results We report an overall wound complication rate of 14.8%(9/61).Wound infection,haematoma,dehiscence,heel necrosis and osteomyelitis were noted in our series.We identified the following as risk factors of postoperative wound compli- cations:1)fall from more than 3.4 m high(P＜0.05);2)delayed operation time less than seven days(P＜0.05); 3)operating time beyond two hours(P＜0.05);4)tourniquet time beyond 1.5 hours(P＜0.05).Conclusion In order to decrease wound complications following operative fixation tor fractured calcanea,surgeons should pertorm the operation 7 to 10 days after the injury,and reduce the operation time and tourniquet time.

Asthma ; diagnosis ; therapy ; China ; Humans ; Practice Guidelines as Topic ; standards

Airway Remodeling ; Asthma ; pathology ; physiopathology ; Child ; Humans

Objective To review the experience of surgical management for caustic esophageal stricture and discuss the surgical techniques of transverse colon interposition for esophageal replacement. Methods 106 patients with caustic esophageal stricture were treated surgically. 32 patients underwent colon interposition with colonphargageal anastomosis and others received colon interposition with a cerrical anastomosis. The ascending branch of the left artery of the transverse colon was preserved as the supporting vessel of the interpositioned colon. Results There was no postoperative death. The leakage of cervical anastomosis was observed in 12 patients, anastomosis stenosis in 8 patients, and tracheotomy was performed in 3 patients. All patients were perfectly recovered by the treatment. Conclusion Transverse colon interposition for esophageal reconstruction is an optimal approach in the treatment of caustic esophageal stricture.

Objective To investigate the multiple factors correlated to femoral head necrosis in patients over 45 years old with femoral neck fractures after closed reduction and cannulated screws fixation.Methods Three hundred patients with femoral neck fracture were admitted from May 1999 to May 2004 and treated by closed reduction and internal fixation with cannulated screws.We analyzed the multiple factors:age,gender,Garden classification,follow-up time,procedure delay,quality of reduction,time of full-weight-loading,fixation removal, and preoperative traction.Multiple correlation factors were analyzed by SPSS10.0 statistic system.Results Complete case records were documented in 99 cases who were followed up for an average of 24.5 months(range,8 to 60 months).Femoral head necrosis occurred in 15 cases(15.2%).Time of femoral head necrosis was 8 to 50 months after operation.The combination of quality of reduction,preoperative traction,age,and age?fixation re- moval was found to have the most significant influence on femoral head necrosis after internal fixation for femoral neck fractures.Conclusions Good reduction is the most important factor correlated to the outcome of a femoral neck fracture.Age is linked to the risk of necrosis but it is relatively insignificant.Preoperative traction in wrong positions can increase the incidence of necrosis.Garden classification is important in predicting femoral head necrosis and is associated with quality of reduction,but it is not a risk one in the combination of multiple correlation factors that lead to the necrosis.

BACKGROUND:Sunshine time in northem region is short in winter,the infants and young children are vulnerable to lack of vitamin D. Up-to-date textbooks and the guidelines formulated by Chinese Medical Association account that glass block ultraviolet and indoor exposure to human is meaningless. Early studies have shown that sunlight exposure through glass had meaning in rats,but it was difficult to accurately quantify,while outdoor exposure in rats is difficult to continue. This expedment uses B-band ultraviolet rays,which has the impact on vitamin D metabolism in some wavelengths,to facilitate further study.OBJECTIVE:To study the effect of ultraviolet B exposure in laboratory on 25-hydroxy vitamin D(25-OHD)level and bone metabolism in the serum of growing rats.DESIGN,TIME AND SETTING:A randomized controlled animal experiment was performed in June 2007 in the ExperimantalAnimal Center of Chinese PLA General Hospital.MATERIALS:Forty male 21-day-old Wistar rats were employed in this study. Ultraviolet waves were sourced from an artificial UV light instrument(wavelength 280-350 μm,irradiation intensity 5.5μW/cm~2).METHODS:Forty Wistar rats were divided into four groups by random sampling table,exposed to different doses of ultraviolet Bwave. Direct exposure group:direct exposure for 20 minutes at an irradiation dose of 4.2 mJ/(cm~2·d);Indirect exposure 60 and 120 min groups:exposure through a single pane of glass for 60 and 120 minutes at an irradiation dose of 0.36 and 0.72 mJ/(cm~2·d).Control group:no exposure was given. For the direct exposure group,the lamp was placed above the cage. A 3-mm-thick pane of glass(common window glass) was placed underneath the lamp in the indirect exposure groups. Exposure groups were given irradiation for successive 20 days.MAIN OUTCOME MEASURES:Serum 25-OHD,bone alkaline phosphatase (BALP),and bone mineral density (BMD) were measured on day 21.RESULTS:25-OHD was significantly higher in all exposure groups compared with the control group (P＜0.001),but there was no difference between the direct exposure group and two indirect exposure groups. BALP was significantly lower in the exposure groups than control group (P＜0.001),it was also significantly lower in the 120-min indirect group than in the 60-min indirect group (P=0.022). There was a positive correlation between exposure dose and 25-OHD (r=0.555,P=0.002) and a negative correlation between exposure dose and BALP (r=0.595,P=0.001),also a negative correlation between 25-OHD and BALP (r=0.569,P=0.002),but there were no differences between groups for BMD. Exposure dose exhibited a threshold,serum 25-OHD and BALP no longer increased or decreased when it was 0.36 mJ/(cm~2·d).CONCLUSION:Midwave ultraviolet rays might affect serum 25-OHD and BALP levels in the growing rats through glass exposure,with no significant difference compared to direct exposure. The B-band ultraviolet exposure dose may play an important role in serum 25-OHD synthesis,but there is a threshold dose for the synthesis. Low-dose and prolonged exposure time also achieve threshold exposure.