The dual source computed tomography is equipped with two X-ray tubes and two corresponding detectors.With its 83 ms-temporal resolution of single segment reconstruction,high quality coronary artery CT angiography can be acquired without heart rate control.Dual energy output by two x-ray tubes improves the differentiation of body tissues,clinical application and lesion diagnostic accuracy of CT.

Objective To discuss the construction and principal of dual-source CT,as well as its superiorities in imaging of heart coronary artery and the clinical application of dual energy technique.Methods The structure of Siemens 64-slice CT was analyzed.The superiorities of dual-source CT in imaging of heart coronary artery were compared with conventional multi-slice CT,and the clinical value of dual energy technique was discussed.Results The dual-source computed tomography had high temporal resolution superiority,and high quality coronary artery CT angiography could be acquired without heart rate control.Dual energy technique could be applied to differentiate tissue component,display given tissue,evaluate the content of iodine in tissue.Conclusion Dual-source CT can not only enhance the diagnosis veracity of pathological changes of heart coronary artery but improve the ability of CT in tissue differentiation.

The low sensibility of MR molecular imaging to signals makes signal amplification exceptionally important.This paper reviews the strategy of the reporter gene signal amplification in MR molecular imaging.

Quantum dots,as nanometer-sized semiconductor crystals,are widely used in life sciences for their excellent optical characteristics.This article introduces the unique optical characteristics of quantum dots and their application in labeling cancer cells and tumor markers as well as in the targeting and imaging of tumor vasculature.

Objective:To investigate the expression of multidrug resistance (MDR1) gene and multidrug resistance-associated pro-tein (MRP) gene in patients with non-small-cell lung cancer (NSCLC) and its relation to histopathological type. Methods:The MDRi and MRP genes were determined by reverse transcription-polymerase chain reaction (RT-PCR) in 48 NSCLCspecimens. Results:The positive rates of the MDR1 and MRP gene expression were 62.5％ and 66.7％ respectively in the48 patients. Twenty-one of the 48 NSCLCs (43.8％) expressed both MDR1 and MRP genes. The positive rates of the MRPgene expression in squamous cell carcinoma was significantly higher than those in adenocarcinoma (P＜0.01), and therewas no significant difference in MDR1 gene expression between the two groups (P＞0.05). Conclusion: The MDR1 andMRP gene expressions were both or respectively in the NSCLCs. The incidence of the MRP gene expression in squamous cellcarcinoma was higher than that in adenocarcinoma.

OBJECTIVE:To study the pharmacokinetics and the bioequivalence of cefdinir dispersible tablets in healthy volunteers.METHODS:Microbiological assay method was used to determine the plasma concentration at different time in 20 healthy volunteers after oral administration of single dose of 400mg of cefdinir dispersible tablets(test preparation) and cefdinir capsule(reference preparation) by cross-over way.RESUTLS:The concentration-time curves of test preparation and reference preparation of cefdinir fitted one compartment open model.The pharmacokinetic parameters of the test preparation vs.the reference preparation were as follows:tmax(3.48?0.53)h vs.(3.60?0.48)h,Cmax(2.10?0.32)mg?L-1 vs.(2.15?0.26)mg?L-1.t1/2ke(2.41?0.39)h vs.(2.33?0.41)h,AUC0～12(9.51?1.65)mg?h?L-1 vs.(10.05?1.72)mg?h?L-1,AUC0～∞(10.43?1.62)mg?h?L-1 vs.(11.01?1.81)mg?h?L-1,respectively.The relative bioavailability of cefdinir dispersible tablet as against its reference preparation was(96.03?14.89)%.CONCLUSION:The two preparations of cefdinir were proved to be bioequivalent.

Objective To evaluate the treatment results and side-reactions of esophageal carcinoma with late course hyperfractionated radiotherapy ( LCHR) plus different chemotherapy. Methods A prospective research was carried out on 287 advanced stage esophageal carcinoma patients whom were randomized into there groups;LCHR + cisplatin +5-fluorouracil +leucovorin group( A group), LCHR +5-fluorouracil polyphase lipo- some group (B group) and LCHR group(C group). 115 patients were in A group and 107 patients in B group and 65 patients in C group. Radiotherapy method; there groups were treated by conventional fractionated radio- therapy during the first two-thirds of the whole course with 40 Cy,then followed by isocenter hyperfractionated radiotherapy to keep away of spinal marrow, 1. 3-1. 5Gy per time,2 times a day and 5 days a week. The total dose was 60-66 Gy in A, B group and 60-70 Gy in C group. The preventive dose was 50 Gy. Results There was no statistically difference among the there groups on the short-term curative effect The 1- ,2- ,3-year local control rate was 80% ,50.4% ,42.6% and 72.9% ,51.4% ,41. 1% and 63.1% ,38.5% ,30.8%

Objective To investigate the classification and its application in one-stage repair of massive posttraumatic bone defects which are infection-induced and refractory in lower extremities. Methods From March 2002 to December 2008, we treated 42 patients with massive posttraumatic refractory infection-induced bone defects in lower extremities. We classified the defects into 3 types: simple massive infection-induced bone defects (type Ⅰ), massive infection-induced bone and soft-tissue defects (type Ⅱ) and massive infection-induced bone defects plus limb shortening (type Ⅲ). After thorough debridement, various types of vascularized fibular grafts were used to repair the 3 kinds of defects accordingly. Simple fibular grafts were used in 6 cases, transplantation with fibular and skin flaps was used in 31 cases, fibular grafts combined with anterior lateral thigh flap in 4 cases, and one-stage limb lengthening and fibular graft in one. Results The follow-ups of 6 to 41 (average, 26. 3) months revealed that the refractory bone defects were repaired successfully in 38 cases, amputation due to necrosis of fibular grafts in 2 cases and uncontrolled infection in 2 cases. In the 38 cases, infections were controlled effectively, circulation of the traumatic limbs was good,contour and function were restored satisfactorily, and no obvious complication was found in donor limbs. By Johner-Wruhs evaluation, 17 cases were excellent, 18 cases good, 3 cases fair and 4 cases poor, with a total excellent and good rate of 83.33%. Conclusions Refractory and massive posttraumatic infection-induced bone defects in lower extremities can be classified into 3 types. They can be repaired using various types of vascularized fibular grafts according to the defect types at one-stage.

BACKGROUND: The structural and functional changes in resistance arteriole of external diameter ＜300 μm is one of the pathological foundations for ischemic cerebrovascular diseases, however there are few quantitative study on the arterioles of various external diameter at different brain area.OBJECTIVE: To probe the difference of arteriolar sclerosis of various external diameter at different brain area after cerebral infarction.DESIGN: Sample investigation.SETTING: Department of Nerve Internal Medicine, General Hospital of Beijing Military Area Command of Chinese PLA.SUBJECTS: Specimen was taken from donated autopsy case in General Hospital of Beijing Military Area Command of Chinese PLA from January 1980 to September 2000. According to the clinical manifestation, brain CT inspection and pathological diagnosis of autopsy, 38 cases were defined as arteriosclerosis cerebral infarction and taken as experimental group, other 15 cases with non-cardiac cerebrovascular disease were taken as controls.METHODS: specimen was obtained in 1-3 days after death from frontal and parietal cerebral cortex and basal gonglion white matters (3 pieces /case) and cut into slices. Five fields of vision were selected from each slice for microscopic observation. Arteriole was divided into ＜ 50 μm group,50-100 μm group and ＞100 μm group according to the arteriole external diameter. (External diameter- internal diameter)/internal diameter was used to assess vascular sclerosis.MAIN OUTCOME MEASURES: [1] Difference of arteriole sclerosis between corresponding external diameter cerebral infarction group and control group. [2] Arteriole sclerosis in various brain region in cerebral infarction group.RESULTS: Totally 38 experimental cases died from arteriosclerosis cerebral infarction and 15 controls died from non-cardiac cerebrovascular disease were enrolled and all data was entered the result analysis. [1] The arteriolar sclerosis index was obviously higher in ＜ 50 μm external diameter cerebral infarction group than in 50-100 μm group and ＞100 μm group[(138.55±76.67)% vs (116.82±58.80)%, (78.07±32.06)%, P ＜ 0.01], while it was approximately the same in the 100 μm external diameter group and control group [(78.07±32.06)% vs (46.38±13.41)%, P=0.174 ]. [2] In ＜ 50 μm external diameter cerebral infarction group, the arteriolar sclerosis index in white matters was significantly higher than that in gray matter [(152.86±87.83)%,(127.97±64.76)%, P ＜ 0.05 ].CONCLUSION: Arteriolar sclerosis degree is correlated with its external diameter and position in patients with cerebral infarction after arteriosclerosis, arteriole of small external diameter or in the white matter has higher arteriolesclerosis liability.

Objective To investigate the occurrence of p16 gene methylation in the population chronically exposed to arsenic in Inner Mongolia,and to study the molecular mechanisms of carcinogenesis associated with arsenic exposure.Methods The study group was composed of 40 cases of typical arseniasis selected from the epidemic area,and the two control groups consisting respectively of 40 non-arseniasis cases selected from the same epidemic area,and 40 healthy persons enrolled from non-epidemic area.Methylation of p16 gene in the blood specimens were analyzed for all the subjects with MS-PCR techniques,and statistical analysis was performed using chi square test.Results The positive rates of p16 hypermethylation in blood specimens were 65.0%,47.5% and 20.0% respectively in study group and two control groups,and the rate of hypermethylation increased with the increase in arsenic exposure with drinking water in epidemic areas.The positive rate of p16 hypermethylation showed significant differences(P