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 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 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.

BACKGROUNDTo study the diagnostic value of detection of p16 methylation of sputum exfoliated cells for peripheral lung cancer.

METHODSBefore operation, p16 methylation of the sputum exfoliated cells was detected in 20 normal persons and 50 patients with peripheral pulmonary nodi by p16 methylation-specific PCR (MSP) for judging the nature of the nodi. The results were compared with pathological reports after operation.

RESULTSThe p16 MSP positive rate of sputum exfoliated cells of peripheral lung cancer patients (27/44, 61.4%) was much higher than that of benign pulmonary nodi (1/6, 16.7%) and normal persons (3/20, 15.0%)(Chi-Square=4.281 and 11.869 respectively, both P < 0.05). No significant difference of p16 MSP positive rate of sputum exfoliated cells was found between benign pulmonary nodi and normal persons (Chi-Square= 0.136, P > 0.05). No significant difference of p16 MSP positive rate of sputum exfoliated cells was found between squamous cell carcinoma (13/18, 72.2%) and adenocarcinoma (8/19, 42.1%) (Chi-Square=3.416, P > 0.05 ). If the positive p16 MSP of sputum was chosen as criterion for peripheral lung cancer, its positive predictive value, negative predictive value, sensitivity and specificity were 96.4%, 22.7%, 61.4% and 83.0% respectively.

CONCLUSIONSThe detection of p16 methylation of sputum exfoliated cells is contributable to the diagnosis of lung cancer.

Objective To analyze the relationship between clinical pathology character and expression of E-cadherin，CerbB-2，p53，Ki-67 in breast cancer in order to evaluate its clinical significance.Methods To observe 93 cases of breast cancer.Immunohistochemical methods were used to detect the expression of E-cadherin，CerbB-2，p53，Ki-67.Results We found that the expressions of E-cadherin，CerbB-2，p53，Ki-67 in breast cancer samples were associated to histopathology grade and lymph node metastasis (p<0.05), but the expressions of CerbB-2，p53，Ki-67 were not associated to tumor size and histological type (p>0.05).Compared to other types, it showed low expression of E-cadherin in lobular carcinoma(p<0.05).Conclusion E-cadherin，CerbB-2，p53，Ki-67 can be regarded as molecular indexes of breast cancer, and they can be used to give diagnosis, choose treatment and forecast prognosis in clinical work.

T1 mapping is a new magnetic resonance imaging technique .By which the longitudinal relaxation time constant ( T1) of the myocardium can be measured to detect and quantitatively assess various focal or diffuse diseases .T1 mapping has various scan sequences , such as LL sequence , MOLLI sequence and ShMOLLI sequence .T1 mapping can be classified into two groups:pre--contrast and post-contrast T1 mapping.In addition, by measuring post-contrast T1 mapping and pre-contrast T1 mapping, myocardial extra-cellular volume (ECV) can be derived, which has been applied to assess myocardial edema and myocardial fibrosis with great clinical value .This review focuses on the techniques , methods and clinical application of cardiac magnetic resonance T 1 mapping technology .

Post-traumatic stress disorder ( PTSD) is an anxiety disorder that can develop following a traumatic event.Neuro-imaging techniques offer a noninvasive means to elucidate the brain circuit underlying PTSD, and may help to find effective biomarkers for diagnosis and treatment evaluation of this disorder.In this article, we review recent brain structural MRI studies in PTSD.Problems of the current research and possible directions for future research are also presented.

Mesial temporal lobe epilepsy (mTLE) is the most common type of refractory focal epilepsy. Diffusion tensor imaging (DTI) can provide qualitative and quantitative information on the microstructural arrangement of epileptic brain tissue. DTI is significant for insights to the pathophysiological mechanism of mTLE, and has potential for investigation of changes in structural connectivity of mTLE. The development and application of DTI in research of mTLE were reviewed in this article.

Objective To study the factors that might influence the PSA-value. Methods Serum samples were collected from 165 cases of benign prostate hyperplasia (BPH),43 cases of prostate cancer (PCa) and 41 cases of chronic prostatitis (CP),both before and after digital rectal examination (DRE),cystoscope examination,indwelling catheterization and finasteride intake. Results In the BPH group,T-PSA elevated from (2.28?2.07)ng/ml to (4.77?5.23)ng/ml, P