Internet based problem-based learning (PBL) mode was used in teaching of ophthalmology in order to increase the quality of ophthalmology teaching and to raise the student's ability of problem solving.The method and requirements of teaching were discussed based on the teaching schema.Examples of cataract teaching using internet based PBL mode was performed.The characteristics and merit of the mode were summarized in the end.

Objective To explore the clinical application of two different fixation methods for nasal continuous positive airway pressure (NCPAP) in newborns. Methods One hundred and forty newborns who had NCPAP treatment were selected and divided into experimental group and control group with 70 cases in each group by random digits table method.The newborns in experimental group received self- made caps to fix the prong systems,while the newborns in control group received U shape towel. The incidence of nose, head of facial skin injury, frequency of detachment for nasal prongs and duration mechanical ventilation were compared between two groups. Results The frequency of detachment for nasal prongs per 24 h was (0.65±0.18) times in experimental group and (1.64±0.22) times in control group, and there was significant difference (t=28.68, P<0.01). The incidence of nose, head of facial skin injury were 8.6%(6/70), 2.9%(2/70) in experimental group and 27.1%(19/70), 14.3%(10/70) in control group,and there were significant differences ( χ2 =8.23, 5.83, P<0.01 or 0.05). There was no significant difference in duration mechanical ventilation between two groups(P>0.05). Conclusions Use of the self- made caps for NCPAP in newborns is associated with significant reduction in the incidence of nose, head of facial skin injury,and the frequency of detachment for nasal prongs.The fixation should be prompted in clinic.

Objective To discuss the value of MRI in clinical diagnosis.Methods Images between CR excretory urography and MRU were compared,which came from the results of 36 cases who were examined by both CR and MRU.Results The spiral MRU images were better than those of the CR excretory urography,and at the same time,the relationship between the parenchyma of the renal,renal pelvis,ureter,bladder and the urinary organs and adjacent tissues were displayed clearly.Conclusion The scanning time of MRI is shorter.The machine can not only reconstruct powerfully but also work out better images,and the result is better than MRI which can't detect pathological changes in detail in its images.Therefore MRI can be replaced by MRU if the higher cost can be afforded.[Chinese Medical Equipment Journal,2008,29(2):80-81]

Objective To evaluate the expression level of cathepsin D protein in nasopharyngeal carcinoma (NPC) and to determine its relationship with clinic pathological characters. Method Immunohistochemistry was performed to detect the expression of cathepsin D in 72 cases of primary NPC and 28 cases of normal nasopharyngal epithelial tissue ( NNET), and the correlation of its expression level with clinicopathologic features and clinical outcomes was evaluated. Results Significant down-regulation of cathepsin D was observed in NPC versus NNET(x2 = 13. 55, P ＜0. 01 ). In addition, cathepsin D down-regulation was significantly correlated with poor histological differentiation ( x2 =41.47, P ＜0. 01 ). Type Ⅰ and Ⅱ (well-moderately differentiated) NPC showed more intense immunoreactivity of cathepsin D compared with type Ⅲ (poorly differentiated) NPC. Cathepsin D up-regulation was significantly correlated with clinical stage, recurrence, and lymph node and distant metastasis (x2 = 13.43,22. 86,21.61,14. 32, P ＜0. 01 ).Tumors with cathepsin D up-regulation tended to have advanced clinical stage, frequent recurrences, and metastasis to lymph node and distant organ. Conclusion The expression of cathepsin D was closely related with the differentiation, clinical stage and pathological grade of NPC. Cathepsin D could be served as an effective differentiation marker for the histopathological grading of NPC and a possible therapy target.

AIM:To investigate the differences of clinical signs and pathological structure of unilateral nasal pterygium and unilateral double pterygium.METHODS:Retrospective study.Totally 11 unilateral nasal pterygium and 11 unilateral double pterygium were collected to observe the size of the tissue area, the classification of blood vessels, the transparency and the break-up time of tear film.The 11 surgically excised double pterygia (11 eyes) and 6 samples of normal conjunctiva were collected for the study.With 40g/L paraformaldehyde fixation, paraffin sections were stained with Haematoxylin-Eosin, to observe the differences with nasal and temporal pathology under light microscope.RESULTS:In unilateral double pterygium, the tear break-up time was significantly shorter than that of unilateral nasal pterygium (t=3.410, P=0.003).In unilateral nasal pterygium, there was a significant negative correlation between tear film break-up time and tissue size(r=-0.927, P<0.01) and transparency(r=-0.764,P<0.01).In unilateral double pterygium, the tear break-up time was significantly negatively correlated with the growth time (r=-0.661, P<0.05), tissue size (r=-0.775, P<0.01) and transparency (r=-0.671,P<0.05).In unilateral double pterygium, compared with the temporal side, the quantity of the layers of corneal epithelial cells (t=-7.351, P<0.05), vessels (t=-7.400, P<0.05) and inflammatory cells (t=-7.481, P<0.05) increased.CONCLUSION:Compared with unilateral nasal pterygium, the tear film break-up time of unilateral double pterygium was poor.In unilateral double pterygium, with high activity, the degree of proliferation of squamous epithelium, hyperplasia and inflammatory reaction are significantly higher than those of the temporal side.

Objective:To study the pupils' anxiety and related factors.Methods:6994 pupils and their were investigated using Conners Behavior Checklist(PSQ).Results:The pupils above 8 years old were more anxious.The economic state of family played an important role in pupils' anxious.Their existed significant age difference in boys but not in girls.Level of farther's and mother's education has obvious influences in their anxiety.Conclusion:The effect facts of anxiety include the age of students,economic state of family,the level of parent's education.

Objective No reports has been found to date on whether frequency compounding can improve elastographic image signal to noise ratio (SNRe) and how it affects elastogram performance.In this paper simulations investigation was carried out on transmit-side frequency compounding (TSFC)for elastography.Methods 50 mm×50 mm tissue model was simulated with two round hard inclusions of 10mm diameter uniformly distributed along the tissue central axial line,and their elasticity modulus were 10 times of the background.Then simulation of 3.5 MHz、5 MHz and 7.5 MHz probes were introduced to form compression elastography of the double-lesion model by quasi-static compression method (applied strain 1%).Then,sub-elastograms obtained by the combination of 3.5 MHz and 5 MHz,3.5 MHz and 5 MHz,3.5 MHz and 7.5 MHz were compounded,respectively.Results Before compounding,signal to noise ratio (SNRe) of the various sub-elastograms were 8.42,9.62,10.73,respectively,contrast to noise ratio (CNRe) were 11.35,14.82,18.37,respectively and axial resolutions were 9.83,9.82,9.81.After compounding elastograms,the SNRe were 11.82,13.05,19.45,CNRe were 22.31,27.63,56.12,while axial resolutions were 9.83,9.83,9.83.Conclusion Frequency compounding elastograms have higher SNRe and CNRe than any sub-elastogram before compounding and have no axial resolution loss.The TSFC can improve elastogram performance efficiently and frequency compounding for elastography enhancement is feasible.

Objective To explore the effects of the meteorologic factors on air pollutants and to establish a model of relationship between the meteorologic factors and concentration of air pollutants. Method The data of SO2,NO2 and PM10 concentration in the air and the related meteorologic factors (daily average,maximum and minimum atmospheric pressure and daily atmospheric pressure difference,daily average,maximum and minimum air temperature,monthly rainfall,daily average and minimum relative humidity and wind speed) from January 2002 to December 2007 were collected. The correlation between the air pollutant levels and related meteorologic factors was analyzed by the multiple regression models with SPSS 11.5 software and multiple regression equations were established. Results Minimum relative humidity was negatively correlated with the concentration of SO2 and NO2 in atmosphere . Daily minimum air temperature was negatively correlated with the concentration of NO2 in atmosphere. Daily average relative humidity and wind speed were negatively correlated with the concentration of PM10 in atmosphere. Daily atmospheric pressure difference was positively correlated with the concentration of PM10 in atmosphere. Multiple regression equations of the concentration of SO2,NO2 and PM10 in atmosphere and meteorologic factors have statistical significances. Conclusion The meteorologic factors have some effects on the air pollution levels. By using the correlation of meteorologic factors and the concentration of air pollutions,multiple regression equations can be established.

Objective To analyze time-space variation of air pollutants(SO2,NO2,PM10) and the correlation among them in inner region and outer region of Shenzhen from 2002 to 2007.Methods The daily concentration means of SO2,NO2 and PM10 during 2002 to 2007 from the nine environmental monitoring sites in Shenzhen were collected.The determination was conducted according to the Ambient Air Quality Criteria.Results From January to December,variation of air concentration of SO2,NO2 and PM10 met the "V" shape in inner region and outer region of Shenzhen in 2002-2007,which was descending from January to June and ascending from June to December.The level of the air pollutants in inner region and outer region was higher in fall and lower in summer.The air pollution level of the inner region was increasing from 2002 to 2004,then decreased in 2005,but increased again in 2006 and 2007.The tendency of the outer region was similar with the tendency of the inner region from 2002 to 2006,but the level of pollutants decreased in 2007.The air concentration of SO2 in outer region was higher than that in inner region in 2002-2007.The air concentration of NO2 and PM10 in outer region was higher than that in inner region in 2002 to 2006,but lower in 2007.The air concentration of SO2 in inner region and outer region in 2002-2007 was under the limit of grade 2 according to the GB 3095-1996,near to grade 1 in inner region.The air concentration of NO2 and PM10 was under the limit of grade 3 and grade 2 respectively.There was a close correlation among the levels of SO2,NO2,PM10 in Shenzhen.Conclusion The air quality in Shenzhen is better in China.The time-space variation of the air pollutants is obvious and a close correlation exists among the air pollutants.

Objective To determine the relationship between serum adiponectin level and chronic inflammation,atherosclerosis in maintenance hemodialysis(MHD)patients.Methods Totally 60 MHD patients and 30 healthy volunteers were included in this study.Serum adiponectin level(ADPN)and C-reative protein(CRP),interleukin-6(IL-6)were measured.Carotid initial-medial thickness(IMT)and brachial arterial vasodilation were determined by echocardiography.Results Serum ADPN level(0.99?0.37)was higher in MHD patients than that(0.39?0.14)in controls.The ADPN level of higher IMT group was lower than that in normal IMT group.CRP,IL-6 and Cartid IMT were negatively correlated with ADPN(r=-0.22,-0.31-0.26,P