Objective To develop a method for determination of mercury in blood by atomic fluorescence spectrometry. Methods Using a thiourea extraction method, the mercury in blood is determined by atomic fluorescence spectrometry. Results The linearity of calibration curve of mercury was in the concentration of 0.000-10.00 ?g/L. The detection limit was 0.06 ?g/L. The recovery rates were 95.5%-100.3%.The RSDs were 4.1%-4.5%. Conclusion The method has the advantages of simple operation, high sensitivity, good repeatability and is applicable to the determination of mercury in blood.

AIM: To evaluate the effect of the chosen incision on corneal astigmatism after implantable collamer lens ( ICL) surgery.
METHODS:The study included 195 eyes of 102 patients, and all eyes were randomly divided into two groups: the chosen incision group ( Group A, 97 eyes) and temporal corneal incision ( Group B, 98 eyes ) . Before the operation, and 1wk, 1mo and 3mo after the operation, each patient was examined with corneal topography to observe the changes of corneal astigmatism.
RESULTS: Preoperative corneal astigmatisms were (1-26±0. 35) D in group A and (1. 28±0. 38) D in group B, thus there was no statistically significant difference ( P>0-05). One week postoperatively, the astigmatism were (0.93±0.29)D in group A and (1.32±0.33)D in group B. One month postoperatively, the astigmatism were (0. 85±0.16)D in group A and (1.27±0.18)D in group B. Three months postoperatively, the astigmatism were ( 0. 80±0-13)D in group A and (1. 25±0. 20) D in group B. The differences between the two groups were statistically significant (P<0. 01).
CONCLUSION: The chosen incision can reduce postoperative astigmatism to a certain extent after ICL surgery.

Objective ST-T complex change, which represents the ventricle repolarization phase, is the main clinical indicator in detecting myocardial ischemia (MI) based on electrocardiogram (ECG) signals.However, its feature point location is not accurate due to interferences. In this paper, a new approach about myocardial ischemia analysis was proposed based on QRS complex. Methods QRS complex, representing the ventricle depolarization process, was used to analyze myocardial ischemia, and some parameters were extracted synthetically in time domain. Then they were used for statistical analysis of myocardial ischemia states and non-myocardial ischemia states. Results Five parameters had significant differences after verification of Non-MI signals in MIT-BIH database and MI signals in long-term ST database (LTST) and they were: QRS upward and downward slopes, transient heart rate, R angle and Q angle in a triangle QRS. Conclusion Five parameters extracted from QRS complex had significant differences. The proposed method provides an important basis for myocardial ischemia detection.

A patient was treated by multiple dental implants,the implanted 6 was adjucent to impacted 8 .Immediately after implanta-tion,4 month and 3 year after implantation the distace between 8 and 6 implant central line was 4.4,3.2 and 2.5 mm,the angle between 8 long axis and 6 implant central line was 42.3°,45.5°and 50.3°.Then 8 was extracted.

Objective To assess the feasibility and outcomes of fractionated stereotactice radiation therapy(FSRT) for brain metastases more than 3 cm in diameter. Methods From September 1996 to July 2006,47 patients(34 male and 13 female)with brain metastases larger than 3 cm were treated with FSRT. The median age was 58(range,31-87) years old. Pathologic diagnosis was adenocarcinoma in 19 patients, squamacarcinoma in 7, small cell carcinoma in 7, adeno-squamacarcinoma in 3, melanoma in 2, poor differen-tiated carcinoma, clear cell carcinoma, transitional cell carcinoma each in 1, and unknown in 6. FSRT was delivered as initial treatment for 26 patients, and as salvage therapy for 21. The largest diameter of brain me-tastases was 3.1-6.0 cm(median, 3.8 cm). Planning target volume were 2.5-33.8 cm3(median, 9.4 cm3). The median dose of FSRT was 30(range,16-57)Gy in 5(range,2 - 11) fractions. The treatment for primary tumor was surgery in 23 patients, radiotherapy and/or chemotherapy in 22, and none in 2. Results The last follow up was in April 2008. All patients were followed up and 33 had follow up more than 5 years. The 1-,2- and 5-year local control rate was 49%, 44% and 44%, respectively. The median survival time was 11 months(range,0.5-88.0 months, 95% CI=8.1-13.8 months). The corresponding overall survival rate was 40%, 17% and 6%, respectively. There were 46 patients died by the last follow up,including 21 died from brain metastases, 17 died from extracranial progression, and 8 died from other causes. Conclusion FSRT is safe and beneficial for selected patients with brain metastases larger than 3 cm.

Objective To compare the characteristics of dose distribution between hypofractionated intensity modulated radiotherapy (IMRT) and hypofractionated stereotactic radiotherapy (SRT) plans in lung tumor and to select an optimal clinical approach. Methods SRT plans were designed for 16 patients with lung tumors who had received IMRT between April 2007 and April 2008. The dose distribution of target volume and normal tissues, conformal index (CI) and heteregenous index (HI) were analyzed using the dose-volume histogram (DVH) for the IMRT and SRT plans. Results The mean dose and equivalent uni-form dose of planning target volume (PTV) in IMRT were similar to those in SRT. SRT had significantly better CI and HI than IMRT (t = 2.77, P < 0.05 and t = - 4.38, P < 0.01 ). The mean lung dose of IMRT and SRT was (492.4 ±368.5) cGy and ( 310.0 ± 73.1 ) cGy, respectively ( t = 1.68, P > 0.05 ). The lung V20 of IMRT and SRT was 6.9% ± 2.1% and 4.2%± 1.9%, respectively ( t = 3.30, P < 0.01 ). No sig-nificant differences were found in the mean dose to the heart or the spinal cord between IMRT and SRT. Conclusions When PTV is less than 57 cm3 or the long diameter of tumor is less than 4.7 cm, hypofrac-tionated SRT has similar dose distribution to hypofractionated IMRT, while the lung dose was lower in the former.

Objective To investigate the effect of ionizing radiation on the expression of transcription factor STAT3 target genes in the pulmonary adenocarcinoma cell line A549.Methods The expressions of VEGF,Bcl-2 and Survivin in A549 cells with or without STAT3 inhibition were detected by RT-PCR and/or Western blot 24 h after 2 or 4 Gy of γ-ray irradiation.Results After γ-ray irradiation with 2 or 4 Gy,the expression of VEGF and Survivin increased significantly.However,the expression of Bcl-2 was not affected by γ-ray irradiation.Furthermore,the increased expression of VEGF and Survivin induced by radiation was found to be inhibited after radiation-induced activation of STAT3 was blocked by AG490 inhibiter.Conclusions γ-ray irradiation could up-regulate the expression of Survivin and VEGF via activating STAT3.The increase of Survivin might partly inhibit the radiation-induced apoptosis of A549 cells,and the up-regulation of VEGF might contribute to the tumor angiogenesis.

AIM:To investigate the roles of feeder cells ln stratification of murine corneal epithelial cells and build an ideal method to engineer stratified epithelial sheet.METHODS:Using contact feeder culture,separated feeder culture,compound feeder culture and culture without feeder cells by Air-lifting method in Transwell chamber culture system,tissue engineered corneal epithelium was reconstructed.Corneal sheets were stained with hematoxylin and eosin(HE)for histological observation.The expression of p63 and keratin 19(K19)and involucrin(IVL)was investigated by immunocytochemistry analysis.RESULTS:Stratification was limited to three to four layers in the contact feeder group,whereas separate feeder sheets were slightly more stratified.The compound feeder group produced a stratified epithelium with five to seven layers of cells.The group without 3T3 feeder cells formed only two to three layers of cells.Immunostaining images in the compound feeder group showed expression of progenitor markers p63 and K19 in the basal and suprabasal layer,as well as differentiation marker involucrin in all layers.CONCLUSION:The remarkable stratification as well as the Iimbal phenotype makes the compound feeder system a candidate tool for cultivating transplantable epithelial sheets.

AIM:To investigate how to design personalized cataract surgery programs to achieve surgical correction of preoperative corneal astigmatism with surgical astigmatism under the guidance of corneal topography, improve postoperative visual quality and reduce the cost of treatment.
METHODS: Totally 202 cases ( 226 eyes ) cataract patients were divided into randomized treatment group and individualized treatment group. According to the method and location of the incision, randomized treatment group were divided into 8 groups. Surgical astigmatism after different incision were calculated with the use of preoperative and postoperative corneal astigmatism through vector analysis method. Individualized treatment groups were designed personably for surgical method with reference of every surgically induced astigmatism, the surgical method chooses the type of surgical incision based on close link between preoperative corneal astigmatism and surgically induced astigmatism, and the incision was located in the steep meridian. The postoperative corneal astigmatism of individualized treatment group was observed.
RESULTS: Postoperative corneal astigmatism of individualized treatment group were lower than that of 3.0mm clear corneal tunnel incision in the randomized treatment group, there were statistically significance difference, while with 3. 0mm sclera tunnel incision group there were no statistically significance difference. After 55. 8% of patients with the use of individualized surgical plan could undergo the operation of extracapsular cataract extraction with relatively low cost and rigid intraocular lens implantation, the per capita cost of treatment could be reduced.
CONCLUSION: Personalized cataract surgery programs are designed to achieve surgical correction of preoperative corneal astigmatism under the use of corneal topography, improve postoperative visual quality and reduce the cost of treatment.