A large coverage on-line learning and examination systems on the internet so far has not gained wide usage and application even though some systems are available commercially because those internet based systems have certain demands of capitals , technology and skilled personals .Our system is half on -line and half off line for examinations .The on-line part is for giving out examination questions and collecting answers , whereas student writ-ing exams and instructors marking the exams are carried out by going off -line.Such a exam-writing application re-duces its dependence on the internet , which is easier for exam-writers in a remote area to use .This half on-line system can be used as a back -up application for the whole on -line examination system , but definitely has more ad-vantages for hospitals in remote areas where the internet is not reliable and popular , and well-trained technicians are lacking.

BACKGROUND: Cytokine is a poly-functional and effective regulator factor to regulate growth of multiple cells. Researches suggest that, as an inflammatory medium, cytokines play a key role in inflammatory reaction of eye; however, there are rare studies on dynamic changes after traumatic cataract.OBJECTIVE: To investigate the relationship among inflammatory reaction and dynamic changes of interleukin 1 (IL-1),IL-6 and tumor necrosis factor alpha (TNF-α) in aqueous humor of rabbits after extracapsular cataract extraction.DESIGN: Randomized controlled animal study.SETTING: Shenzhen Municipal Ophthalmology Hospital, Shenzhen Municipal Ophthalmology Center Affiliated to Medical College of Jinan University.MATERIALS: The experiment was carried out in Institute of Shenzhen Municipal Ophthalmology Center Affiliated to Medical College of Jinan University from March 2004 to March 2006. Fifteen healthy adult New Zealand rabbits of 30 eyes,general grade, weighting 2.5-3.0 kg, of either gender, were provided by Animal Center of the Second Clinical Medical College of Jinan University [certification: SYXK (yue) 2005-006]. Eyes of rabbits were normal before experiment. All rabbits were randomly divided into normal control group, traumatic control group and operative group with 5 in each group and in total of 10 eyes in each group. IL-1, IL-6 and TNF-α kits were provided by Shenzhen Yawei Biotechnology Company Limited.METHODS: Rabbits in traumatic control group and operative group were totally anesthetized with intravenous injection of 10% 1 mi/kg urethan, and then, 5# needle was punctured from corneal limbus to anterior chamber to scarify anterior membrane of lens about 5 mm to establish animal models of traumatic cataract of oculus uterque. Rabbits in normal control group were fed normally. After successful modeling, common antibiotic eyedrops was used to clean conjunctival sac of rabbits in traumatic control group and operative group 3 times a day. On the 3rd day of successful modeling, rabbits in operative group were totally anesthetized with intravenous injection of 10% 1 mL/kg urethan, and then, they undertook extracapsular cataract extraction of oculus uterque: horizontally intercepting bladder or waterly separating with breakage of anterior bladder membrane, expulsing nucleus of lens, washing lens cortex and suturing incisions. On the operative day and on the 1st, 3rd, 7th and 14th days after operation, inflammatory reaction of anterior chamber in traumatic control group and operative group was measured and 0.2 mL aqueous humor was extracted from rabbits in three groups to count and classify cells; meanwhile, expressed level and dynamic changes of IL-1, IL-6 and TNF-α in cytokines of aqueous humor were measured with double-antibodies ELASA technique.MAIN OUTCOME MEASURES: Total numbors of leucocytes and contents of IL-1, IL-6 and TNF-α in aqueous humor of rabbits in three groups after operation.RESULTS: ① On the 1st, 3rd, 7th and 14th days after operation, numbers of leucocytes were (2.4±0.7)×106/L, (2,2±0.5)×106/L, (2.8±0.8)×106/L and (2.0±0.5)×106/L in aqueous humor; (19.7±7.3)×106/L, (28.1±9.6)×106/L, (14.2±5.6)×106/L and(8.4±3.8)×106/L in traumatic control group; (65.3±14.5)×106/L, (79.8±12.7)×106/L, (21.7±8.2)×106/L and (12.4±4.1)×106/L in operative group. In addition, numbers of leucocytes were more in traumatic control group and operative group than those in normal control group (F =22.5, 27.9, 11.6, 8.4;P＜0.05). ② Within 1-14 days after operation, contents of IL-1, IL-6and TNF-α in aqueous humo were higher in traumatic control group and operative group than those in normal control group (P＜0.05), and there was a significant difference between traumatic control group and operative group (P＜0.05);however, there was no significant difference among three groups on the operative day (P＞0.05). ③ Contents of cytokines reached peak on the 7th day after operation, decreased gradually, and reached the lowest value on the 14th day.Contents in traumatic control group and operative group were higher than those in normal control group (P＜0.05).CONCLUSION: The intraocular inflammation after lens extraction is closely related to the dynamic changes of IL-1, IL-6and TNF-α levels in aqueous humor. Cytokine may be one of crucially inflammatory agents in the eyes after traumatic cataract.

Objective To investigate the role of phosphatidylinositol 3-kinase (PI3K)/protein-serine-threonine kinases(Akt) signal transduction pathway in EphB receptor-mediated neuropathic pain in rats.Methods Forty-eight pathogen-free male SD rats aged 2-3 months weighing 150-180 g were randomly divided into 6 groups (n =8 each):groups sham operation (groups S1 and S2 ); groups chronic constrictive injury (CCI) (groups C1and C2 ) and groups EphBI-Fc (EphB receptor antagonist) + CCI (groups E1 and E2 ).Neuropathic pain was induced by placing 4 ligatures on left sciatic nerve at 1 mm intervals with 5-0 silk thread in groups C1,C2,E1 and E2.EphBI-Fc 0.5 μg in 5 μl normal saline was injected intrathecally 1 h before operation and at 1 and 2 d after operation (group E1 ) or on 5th day after operation (group E2).Normal saline 5 μl was injected intrathecally instead of EphBI-Fc 1 h before operation and at 1 and 2 days after operation (groups S1 and C1 ) or on 5th day after operation (groups S2 and C2 ).Pain withdrawal latency to noxious thermal stimulation (PWL) and pain withdrawal threshold to noxious mechanical stimulation (PWT) were measured before operation and at 1,3 and 5 d after operation.The animals were sacrificed at 5 d after operation after measurement of pain threshold.The lumbar segment of spinal cord (L4-6) was removed for determination of c-Fos,PI3K and phosphorylated Akt(p-Akt) expression.Results CCI significantly reduced PWL and PWT and up-regulated spinal c-Fos,PI3K and p-Akt expression in groups C1 and C2 as compared with groups S1 and S2.EphB1-Fc significantly decreased hyperalgesia and the upregulated spinal Fos,PI3K and p-Akt protein expression induced by CCI in groups E1 and E2 as compared with groups C1 and C2.Conclusion Spinal EphB receptor is involved in the development and maintenance of neuropathic pain through PI3K/Akt signal transduction pathway.

Objective To evaluate the therapeutic effects of rAAV2-SERCA2a gene targeted to myocardium by the ultrasound mediated microbubbles in rats with myocardial infarction(MI) using speckle tracking echocardiography (STE). Methods Thirty-five male SD rats were divided into Sham group, MI group and gene therapy group. rAAV2-SERCA2a was attached to the surface of SonoVue, sulphur hexafluoride-filled microbubbles. Therapy group animals were infused with those mixed fluids through tail vein. The other two groups were infused with SonoVue microbubbles. These bubbles were infused with simultaneous echocardiography. Four weeks after ultrasound microbubbles destructed,Circumferential strain rate(SRcir), radial strain rate(SRrad) and left ventricular torsion (LVtor) of regional myocardium were measured in short-axis view using speckle tracking imaging software for each animal. Results Compared with the M1 group,there were significant increase in SRcir-S,SRcir-E, SRrad-S,SRrad-E and LVtor in rats of gene therapy group( P ＜0. 01 ). There was no significant difference between gene therapy group and sham group. Conclusions rAAV2-SERCA2a gene targeted to myocardium by the ultrasound mediated microbubbles could enhance cardiac function of rats with MI.

Objective To investigate the value of ultrasonography in evaluating the femoral artery thrombosis in rabbit. Methods Thrombosis was induced by external application with 10% ferric chloride and transient femoral artery-occlusion with bulldog clamp in twenty New-Zealand rabbits. The thrombosis was monitored by both Doppler flowmeter and ultrasonography. The histopathological result was used as the golden standard. The consistency of the above two results with the golden standard was analyzed. Results Thirty-two femoral arteries thrombosis were produced successfully. There was high consistency between the results of ultrasonic evaluation and histopathological examination (Kappa = 0. 720, P ＜ 0. 001 ), and moderate consistency between the results of Doppler flowmeter evaluation and histopathological examination (Kappa = 0. 546, P ＜0. 001 ). Within the thirty-two femoral arteries thrombosis, there were nineteen arteries with occlusive thrombus examined by histopathological means. Both the results of Doppler flowmeter and ultrasonography were highly consistent with the results of histopathological examination (Kappa = 0. 800 and 0.798 respectively, P ＜ 0. 001 ). Conclusions There is high consistency between the results of ultrasonic evaluation and histopathological examination for the common femoral artery thrombosis in rabbit.In the non-occlusive thrombus diagnosing,ultrasonography is better than Doppler flowmeter.

BACKGROUND:Generaly, the stent surface modification, especialy seeding cels, may accelerate or cause stent endothelium, and cause restenosis for prevention of in-stent thrombosis.
OBJECTIVE: To develop the optimal conditions for vascular stents coated with bone marrow mesenchymal stem cels.
METHODS: Cerebrovascular stent was co-cultured with passage 3 bone marrow mesenchymal stem cels from rats at 1×106, 1×107, 1×108, and 1×109/L. Cels on the stents were examined with transmission electron
microscopy after 48 hours. A total of 160 male Sprague-Dawley rats were enroled, among which, 20 rats were as normal control group, and the remaining 140 were used for producing models of ischemic stroke that were
randomly sub-divided into seven groups at 8 weeks after modeling: stainless steel stent implanted group, polymer stent group, and different concentrations of cellstent composite groups. After 8 weeks of implantation, the
expression of vascular endothelial growth factor in these cels was examined by western blot assay. Rat platelet activation in different groups was determined by flow cytometry.
RESULTS AND CONCLUSION:Implanted stem cels were able to grow adherently on the stainless steel stent wal. When the planting cellconcentration was 1×107 cels/L, the cels and organeles were morphologicaly
normal and covered the stent surface wel. These coated cels also expressed vascular endothelial growth factor, suggesting that they functioned as endothelial cels, and they also significantly lowered platelet activation. When
co-cultured with 1×107/L bone marrow mesenchymal stem cels, the stent was covered wel with endothelial-like cels and had significant lower platelet activationin vivo.

Objective To evaluate the clinical outcomes of pedicle screw fixation in the treatment of Hangmans fracture. Methods The 15 patients who had been treated for acute Hangmans fracture in our department after 1999 were retrospectively analyzed. 4 of them were type I, and 11 type II. All the patients presented symptoms of nerve system at different degrees. They were treated with AO pure titanium cortex screw through isthmus after skull traction replacement. Results All the patients were followed up for 12 to 60 months. According to Frankle classification, 6 cases of Grade D and 5 cases of Grade C recovered up to Grade E, 2 cases of Grade C recovered to Grade D, 1 case of Grade B recovered to Grade C and 1 case of Grade B recovered to Grade D. X ray showed all the fractures healed up without vertebra artery injury or other complications. Conclusion The outcomes of pedicle screw fixation and reduction in treatment of acute Hangmans fracture are satisfactory, for the clinic technique promotes functional recovery of spinal cord, decreases the rate of infection and scarcely affects the function of upper cervical spine.

Objective To gather observational data on resting energy expenditure(REE)of children with newly diagnosed malignant solid tumor, and to examine factors that might be relevant to their energy expenditure change. Methods It is a retrospective study. Data from sixty-one patients with newly diagnosed malignant tumor admitted to department of pediatric surgery in Xinhua Hospital were reviewed in this study. Resting energy expenditure was measured by indirect calorimetry. Patients with benign tumor admitted during the same period were used as the control group. Results The difference of percentage of patients with normal, decreased, or increased REE between benign and malignant groups was not significant(χ2 = 0.466, P = 0.792). Patients with one or more gastrointestinal symptoms had higher percent of Pre-REE compared with patients without any gastrointestinal symptoms, but no significant difference existed(119.8±80.4 vs 91.1±27.2, Z = 0.746, P = 0.456). Different tumor types were associated with different effects on REE. There was no significant difference in REE levels between patients with decreased diet intake and those without(Z = 0.528, P = 0.598). Conclusions It is confirmed that not all patients with malignant tumor have an increased REE. Moreover, the tumor site might be an independent factor affecting patients' REE level.

Objective To explore the effects of biomimetic electrical stimulation on inducing differentiation of rat bone marrow mesenchymal stem cells(MSCs) into cardiomyocyte-like cells in isolated myocardium.Methods MSCs and cardiac myocytes from SD rats were isolated and cultured by modified method.MSCs were then co-cultured with cardiac myocytes(MSCs/ cardiomyocyte co-culture system).The co-culture system was divided into stimulated group and non-stimulated group.MSCs cells in stimulated group were given supra-threshold square biphasic pulses stimulation(5ms duration,0.5Hz,10V) lasting for 2h each day,while in non-stimulated group were routinely cultured.Each group was divided into three subgroups according to the incubation time of 3,5 and 7 days.The characteristic morphology of MSCs in every subgroup was observed under light microscope.The expression of cTnT in MSCs was detected by immunofluorescence.The rate of cTnT positive expression was also compared between two groups.Results The growth and frequency of myocardial wave of MSCs cells in stimulated group were better or higher than those in non-stimulated group.No expression of cTnT was detected in non-stimulated group at the 5th day of the experiment,while a few MSCs cells in the stimulated group expressed cTnT at the same time point.The cTnT expression was detected in the MSCs cells in the both groups on the 7th day.The rate of cTnT positive expression in stimulated group(20.98%?5.55%) was significantly higher than that in non-stimulated group(13.20%?3.98%,P

Objective To observe the 3 years or more effects on optical correction,refraction,and orthokeratology with rigid gas permeable contact lens(RGPCL) wearing in patients with keratoconus.Design Retrospective case series.Participant 73 keratoconus patients(136 eyes) fitted with RGPCL.Methods Patients wearing RGPCL for 3 years or more in Peking University Optometry & Ophthalmology Center were observed.Correct visual acuity was determined before and at 1,2 and 3 years of lens wearing,and the refractive power,corneal curvature,corneal astigmatism and corneal morphological changes were measured with auto-refractomer/keratometer and keratoconus screening analysis system of computer-assisted corneal topography at the same time.The changes of base curve and RGPCL power were also compared.All patients were divided into mild keratoconus group(Group A),moderate and severe keratoconus group (Group B).Main Outcome Measures Visual acuity,refractive power,base curve of RGPCL,corneal topography parameters.Results The patients wore RGPCL for 49.3?15.3 months(36-76 months).At the initial visit,uncorrected visual acuity(UVA) was 3.76?0.45, corrected visual acuity with spectacles(SPVA) was 4.57?0.53,and with RGPCL(RGPVA) was 4.89?0.14.RGPVA was improved significantly (F=171.994,P=0.000).RGPVA at last visit(4.95?0.11) was better than that at initial visit(t=-6.733,P=0.000),which was more significant in group B than that in group A.The rate for RGPVA more than 0.8 at the initial,1 year,2 years and 3 years of lens wearing was 85.13%,86.76%,85.60%and 84.62%respectively.At the initial visit and last visit,the myopia diopters and the corneal astigmatism were 7.13?4.01D vs.6.23?3.42D(P=0.014) and 6.23?3.24D vs.4.42?2.34D(P=0.000) respectively.The RGPCL base curve and lens power were 7.38?0.50 mm vs.7.54?0.42 mm(P=0.000),and -6.22?3.59 D vs.-5.33?3.09 D(P=0.000) respectively. The changes of power and base curve of lens in group B were more significant than that in group A.The decrease of 9 corneal topography parameters between initial visit and last visit was significant statistically(all P