Background The evaluation of visual function after laser in situ keratomileusis(LASIK) mainly focuses on the study of contrast sensitivity funetion (CSF).However,CSF measurement is a subjective method and therefore has a limiting in application.A point spread function (PSF) is becoming a study topic because of its objectivity in assessing visual quality.Objective Present study was to evaluate the change of the modulation transfer function (MTF) of eyes and compare the optical and visual quality of human eyes after LASIK.Methods Thirty-six patients(72 eyes) were included in this study.The patients were divided into low myopia(-2.72±0.52 D),moderate myopia (-4.89+0.80 D) and high myopia (-8.00+0.98 D) groups according to the spherical equivalent (SE)diopter before the sugery.The uncorrected visual acuity (UCVA),best corrected visual acuity (BCVA) were examined before and after operation,and PSF data was obtained with Topoeon PSF-1000 analyzer under the 3.0 mm and 6.0 mm pupil size conditions.The follow-up visits of the patients were scheduled at the 7th days,1 st and 3rd months.Written informed consent was obtained from each patient before this study. ResuIts The MTF values among the three refractive groups were significantly different between 3 mm and 6 mm pupil preoperatively (P＜0.05).Under the condition of 3 mm pupil size,the MTF values in the spatial frequencies of 2.98 cpd and 14.88 cpd were significantly declined in different time points after operation in comparison with preoperative ones (P＜0.05).However,the MTF changes had no statistical significance in the spatial frequencies from 18.85-37.70 cpd among various time points(P＞0.05).Under the condition of the 6 mm pupil size,MTF values in low and moderate myopia groups were reduced after operation in comparison with before operation at the spatial frequencies from 2.98-7.44 cpd(P＜0.05),however,there were no obvious difference was found in the spatial frequencies of 9.42-37.70 cpd(P＞0.05).The MTF values of high myopia group was decreased significantly at all spatial frequencies(P＜0.05).The MTF values improved gradually as the prolong of time after operation but was still lower at the 3rd postoperative month than that of preoperation. Conclusion The postoperative visual quality is associated with refractive power and pupil diameter.PSF is a feasible method in assessing the early visual quality after LASIK.

Background Researches showed that as the non-optical factors,cognitive has certain influence on the regulating system.So accurately experimental design is one of the key steps that evaluates the non-optical factors on regulating system.Objective The present study was to investigate the influence of presenting pattern of target and watching way on the level and amplitude of accommodative fluctuate and to analyze the effect of focus gaze of cognitive on regulating system and the relationship between focus gaze condition under near work and the development of myopia.Methods This study complied with Declaration of Helsinki,and the permission of Ethic Committee and written informed consent was obtained before entering in this trial.Thirty healthy volunteers were included with the mean age (24.80 ± 1.98) years old,equivalent refractive diopter (-1.92 ± 2.02) D and mean cylinder (-0.19±0.58) D.The presenting pattern of the targets was designed as focus gaze and relaxed gaze.The accommodative response and accommodative fluctuation in the complete corrected right eyes for the different targets at the 40 cm under the gazing state was recorded with Grand Seiko WAM 5500 automatic infrared refractor in the experiment.Results The mean accommodative response value was (1.86±0.26) D under the focus gaze and (1.27±0.39) D under the relax gaze,showing a statistically significant difference (t=-8.052,P=0.000).The mean fluctuate value was(0.17±0.06) D under the focus gaze,with a significant lowing in comparison with (0.28±0.17) D under the relax gaze (t =3.600,P =0.001).Conclusions These results demonstrate that the different presenting patterns of sighting target and watching ways of the subjects affect accommodation system.The accommodative response was relatively more accurate with a smaller microwavc moving under the focus gaze condition.

Objective To establish a method for extracting DNA from old bones by AutoMate ExpressTM system.Methods Bones were grinded into powder by freeze-mill.After extraction by AutoMate ExpressTM,DNA were amplified and genotyped by Identifiler(R) Plus and MinFilerTM kits.Results DNA were extracted from 10 old bone samples,which kept in different environments with the postmortem interval from 10 to 20 years,in 3 hours by AutoMate ExpressTM system.Complete STR typing results were obtained from 8 samples.Conclusion AutoMate ExpressTM system can quickly and efficiently extract DNA from old bones,which can be applied in forensic practice.

Objective To investigate the reasons of higher result of CK-MB than the total CK with the immune suppression method for deteting serum CK-MB and solution methods.Methods Selected 68 cases of inpatients with myocardial infarc-tion from Department of Cardiology,32 cases of malignant tumor from Internal Medicine-Oncology,including 8 cases of liver cancer,6 cases of lung cancer,6 cases of gastric cancer,5 cases of neuroblastoma,4 cases of breast cancer and 3 cases of o-varian cancer and 16 cases of cirrhosis from Department of Gastroenterology,and at the same time,selected 100 cases of healthy persons as control group from Out-patient Health Examination Center of Shaanxi Provincial People’s Hospital.Used Roche MODUALR automatic biochemical analyzer to detected the activity of serum CK-MB with the immune suppression method and the activity of total CK with the enzyme coupling rate method.Results In 68 cases of inpatients with myocardial infarction,the activity of serum CK-MB of 2 1 cases were individually increased,the activity of total CK of 3 9 cases were in-creased,and the two indexes of 30 cases were increased in the same period.In 32 cases of inpatients with malignant tumor, the activity of serum CK-MB of 1 1 cases were individually increased,the activity of total CK of 3 cases were increased and the two indexes of 3 cases were also increased.The activity of serum CK-MB of 6 cases were individually increased in 1 6 ca-ses of cirrhosis.Conclusion The immune inhibition assay for the detection of CK-MB as the diagnosis index of myocardial infarction had certain defects,and the higher activity of CK-MB could be highly associated with some severe inflammation, malignant tumor.

Objective To develop europium (Ⅲ) [Eu (Ⅲ)] chelated microparticles for homogeneous immunoassay.Methods Anti-human PCT antibodies were labeled with Eu (Ⅲ) chelated nanoscale microparticles as the detection antibody,and another anti-human PCT antibody was labeled with biotin as the solid-phase antibody.Magnetic microspheres labeled with streptavidin were used to separate the complexes of Eu-IgM-PCT-IgM-Biotin.Results In the homogeneous immunoassay,the standard curve fit was not linear.The quadratic curve was Y =19170.12 + 75493.74X-26.00X2(r =0.9986).According to the standard curve,the limit of detection for PCT was 0.04 ng/ml.Conclusion The homogeneous immunoassay which uses Eu (Ⅲ) chelated microparticles is highly sensitive for detection of PCT recombinant antigens and may serve as a promising method to measure serum PCT levels in the future.

Objective To assess the relationship between the BMI and the brain DAT, and the influence of BMI on the brain SPECT imaging with 99Tcm-TRODAT-1. Methods MRI and 99Tcm-TRODAT-1SPECT imaging were performed in 31 healthy volunteers(16 males and 15 females), and then the three-dimensional reconstruction of SPECT images were completed. Based on the MRI images, right striatum (RST) and the left striatum (LST) were drawn as ROI on the 4 most clearly consecutive transverse slices.The cerebellum (CB) was taken as the background reference area and the corresponding uptake ratios of ST/CB, LST/CB and RST/CB were calculated. The Pearson correlation tests for radio-uptake ratios (ST/CB, LST/CB, RST/CB), BMI and age were performed, Then multiple linear regression analysis using ST/CB as dependent variable and BMI and age as independent variables was performed. SPSS 15.0 was used in data analysis. Results The ST imaging was symmetrical. The radioactivity was higher in the ST front area than that of the back area. The average uptake ratios of ST/CB, LST/CB, RST/CB were 1.71±0.16,1.70 ± 0. 16 and 1.72±0.17 respectively, in which the three ratios of the female were 1.74 ± 0. 18, 1.71±0. 19 and 1.76 ± 0. 19 respectively and those of the male were 1.68 t 0. 14, 1.68 ± 0. 13 and 1.69± 0.15respectively. ST/CB, LST/CB and RST/CB were negatively correlated with patients'BMI (r = -0. 53,-0.57,-0.47, all P＜0.05). The ST/CB was negatively correlated with patients' age(r=-0.39, P=0. 03). The multiple linear regression analysis showed that the BMI was significant independent variable (β=-0.53, t= -3.36, P=0. 002). Conclusions TheSTDAT,evel may decrease as patients' BMI and age increase. Females' DAT level is slightly higher than males'. For ST DAT imaging, age, gender and BMI should be all taken into consideration.

Objective To know the prevalence tendency of Keshan disease(KSD) under control after 10 years in Shaanxi Province, the factors that causes or relative to the disease, to provide scientific reference for disease's prevention and control. Methods Through stratified cluster sampling, based on the severity of KSD in endemic area of Shaanxi Province, 12 villages from 6 counties were randomly selected as investigation points in 2006. The people older than 3 year-old were chosen to do clinical check up and electrocardiogram tracing. Among them, suspicious or abnormal cases were asked to take chest X-ray and cardiac ultrasound. Maize and rice, hair and whole blood were randomly collected to test the selenium content, the activity of Glutathione peroxidase (GSH-Px). Results The total detection rate of potential or chronic KSD was 2.44%(139/5694), the detection rate of abnormal ECG was 9.19% (523/5692), the detection rate of cardiac enlargement from chest X-ray and cardiac ultrasound were 45.6%(72/158) and 34.5%(59/171) respectively. The average content of selenium in staple foods(wheat and corn) were[(0.045±0.036), (0.035±0.025)mg/kg, respectively]. The level of hair selenium in patients and healthy people were [(0.376±0.091), (0.384±0.077)mg/kg, respectively], with non-significant different (u=0.77, P>0.05). There were significant differences in whole blood selenium of patients, healthy people in KSD areas and healthy people in non-KSD areas[(0.071±0.017), (0.077±0.017), (0.090±0.016)mg/L, respectively; F=4.55, P<0.05), the whole blood selenium in patients lower than in healthy people in KSD areas (P<0.05), in healthy people in KSD areas lower than in non-KSD areas (P<0.05). Conclusions After the KSD condition being controlled, the situation in Shaanxi Province has become stable and exhibited a decreasing tendency. The selenium level of both internal and external environment in the endemic area increased significantly, that is the main factors of controlling disease.

Objective To explore the status of Keshan disease in Shaanxi province to provide a scientific basis for decision-making of prevention and control of Keshan disease. Methods Nineteen infected villages were randomly selected in 19 infected counties in the range of Keshan disease infected area in Shaanxi province in 2008 as the investigation sites. Clinical examination and electrocardiography were performed in the chosen people at every spots, chest X-ray of posteroanterior position film in 2-meter distance was taken in suspicious cardiac patients, and determining the selenium contents was also determined in the collected grain samples of the investigators. Results Of the 10 228 investigated residents in the endemic area, 110 Keshan disease patients were detected, the total detection rate was 1.08% (110/10 228). Among the 110 patients, 92 were potential Keshan disease, which accounted 0.90%(92/10 228); 18 chronic Keshan disease formed a detection rate of 0.18%( 18/10 228); no acute and sub-acute type of Keshan disease had been inspected. Potential Keshan disease patients often showed electrocardiogram abnormality of complete fight bundle branch block [48.57%(51/105)], ST-T change[ 19.05% ( 20/105 ) ], frequent premature ventricular contraction [ 10.48 % ( 11/105 ) ], left ventricular hypertrophy [ 5.71% (6/105) ], block in the anterosuperior division of the left branch[5.71%(6/105)]; Chronic of Keshan patients mostly presented atrial fibrillation [ 24.00% (6/25) ], left ventricular hypertrophy [ 20.00% (5/25) ], complete right bundle branch block [ 20.00% (5/25)]. The increase rate of cardiothoracie ratio was 18.08% (32/177). Food samples of wheat, corn, millet and rice in infected area residents were of selenium content, being (0.096± 0.028), (0.089 ±0.029), (0.087 ± 0.016), (0.047 ± 0.016)mg/kg, respectively. Conclusions Keshan disease in Shaanxi province is steadily declining, potential and chronic Keshan diseases are currently the main clinical types. Selenium content of food in endemic area has reached the level of the non-endemic area.

Objective To investigate the genes associated with Alzheimer's disease (AD) by bioinformatics methods to provide new thoughts for basic research and clinical treatment of AD.Methods The microarray data of AD-related genes were downloaded from the Gene Expression Omnibus (GEO) database and analyzed by bioinformatics methods using String,KEGG and Panther databases.Results Of all the 34 differentially expressed genes,25 were found to encode proteins with interactions; they referred to multiple biological pathways,biological processes and molecular functions.Conclusion The pathogenesis of AD involves multiple genes,especially genes with Ca2+ signaling,and investigations of these genes may provide valuablc insights into the mechanism of AD.

Objective:To study the potential effects of intensity modulated radiation therapy (IMRT) on clinical efficacy,oral mucosa reaction and immunological foundation;and to explore the effect of immunological changes on clinical efficacy and oral mucosa reaction in patients with nasopharyngeal carcinoma.Methods:A total of 200 patients with nasopharyngeal carcinoma,who came from First Department of Nasopharyngeal Radiotherapy,the First People's Hospital of Foshan from October 2008 to November 2011,were selected.The patients were treated with nasopharyngeal radiotherapy,and divided into an observation group and a control group (n=100 in each group).The control group underwent common conventional two-dimensional radiotherapy treatment,while the observation group underwent IMRT.The 5-year survival rates and recurrence rates were recorded at follow-up.After the radiotherapy,the oral mucosa in the patients were evaluated by the classification standard of acute radioactive mucositis by American Radiotherapy Oncology Group (RTOG),and the number of T lymphocyte subsets before and after treatment was detected.Results:There were significant difference in non-regional-recurrence survival rate,disease-free survival rate,local recurrence rate between the above 2 groups (all P＜0.05),but no significant difference in the distant metastasis-free survival rate (P＞0.05).The acute oral mucosa reactions of grade 1,2,3,4 in the control group were 8.00％,20.00％,12.00％,7.00％,respectively,and those were 7.00％,22.00％,15.00％,1.00％ respectively.There was no significant difference in the acute response of oral mucosa in grade 1,2 and 3 in the 2 groups (all P＞0.05),but there was significant difference in the grade 4 (P＜0.05).There were significantly difference in CD8+,CD4+/CD8+ and CD4+ T lymphocyte subsets before and after treatment in the above 2 groups (all P＜0.01);there were also significantly difference after treatment between the observation group and the control group (all P＜0.01).Conclusion:In the process of treatment in patients with nasopharyngeal carcinoma,the use of IMRT on the basis of chemotherapy is more effective than the conventional two-dimensional radiotherapy,which can reduce the proportion of grade 4 (severe) acute oral mucosa reaction.It may be related to the protective effect of IMRT on immune function in the patients.