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.

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.

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.

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.

The paper analyzes the new theory of “a modern property right system” put forward for the first time at the Third Plenary Session of the Sixteenth Central Committee of the CPC. It dwells on the opportunities and challenges facing state owned hospitals in establishing a modern hospital system. It is suggested that domestic hospitals should adopt a modern hospital system that fits in with the modern market economy and embodies modern property right features.

Objective To evaluate the value of multi-slice spiral CT in nasal endoscopic surgery.Methods The multi-slice spiral CT data of 232 patients who were scanned prior to nasal endosopic surgery were analyzed.Results The nasal and sinus disease could be diagnosed correctly with multi-slice spiral CT.The ostiomeatal complex and the channels of the frontal sinus' drainage could be showed clearly.All the manifestation of the multi-slice spiral CT was in correspondence with the endoscopy showed in the surgery.Conclusion The multi-slice CT has the advantages of short scan time,less radiation dosage and multiplanar reconstruction.So it can display the nasal and sinus structures in detail,and has a great value in guiding the nasal endoscopic surgery.

Objective:To investigate the value of ultrasonography in the diagnosis of cystic renal cell carcinoma(CRCC).Methods:To review and analyze 32 cases confirmed by histological examination with the complete data and to sum up their characteristic features of ultrasonographic appearance,and then compared with the results of CT.Results:The sensitivity of ultrasonography in the diagnosis of cystic renal cell carcinoma was 75.00%(24/32),CT was 87.50%(28/32),therefore there was no obvious statistical difference between them.Conclusion:Color Doppler ultrasonography has diagnostic value in cystic renal cell carcinoma.

Argon-helium cryosurgical system has been widely used in the treatment of solid tumors.The basic mechanism of this technique is that the ultra low temperature(below 140℃ ) can act on the diseased tissues, resulting in the formation of ice crystals both inside and outside of the cells and causing the rupture of the cells, which will further produce a series of physical and chemical changes and finally bring about the necrosis of tumor cells.This paper aims to introduce the argon-helium cryosurgical system, focusing on its guiding mode, freezing extent and time, freezing immunity, curative effect and combination of treatments.

Dynamic contrasted-enhanced perfusion MR imaging can provide noninvasive and physical maps of cerebral microcirculation. The tumor vascularities are assessed by calculating cerebral blood volumes of the normal cerebral tissue and tumor tissue from imaging signal intensities. This technique is helpful to better evaluate the histopathological grade of gliomas, determine the biopsy site for tumors. And it is very useful for the preoperative diagnosis of gliomas, solitary metastases, cerebral lymphomas, as well as differentiating tumor recurrence after surgical resection and radiotherapy from radiation necrosis. But there are some limitations in evaluating extraaxial tumors and cerebral tumors with severe breakdown of blood-brain barrier.