Medical cyclotron supplies the positron isotope for PET examinations. The purpose of QA for medical cyclotron is to keep the cyclotron work well, so it can supply enough and high quality positron isotope. It is important to do the maintenance and serving of the cyclotron. Importance should be attached to the training of operators. At the same time, repairing work and the supply of spare parts are also important.

As the amount of PET/CT increases,the amount of cyclotron also increases.Hospitals are confronted with some similar problems in cyclotrons purchase.The article is about the stability,after service,yields of nuclide and the particle energy of cyclotron.The stability of cyclotron is the most important factor,and after service is in the next place,while the yields of nuclide are also very important.

To assess the impact of cytochrome P450 (CYP) 2C19*17 allelic variant on platelet aggregation and bleeding risk in Chinese patients with blood stasis syndrome undergoing percutaneous coronary intervention (PCI) and treated with clopidogrel.

Objective To evaluate the technique of multi-slice spiral CT angiography and it's value in diagnosing cerebrovascular diseases.Methods 77 cases were studied with GE Discovery Ultra 16-slice spiral CT scanner.The raw data were then transferred to ADW4.1 workstation and reconstructed with Volume Rendering(VR) and Maxium intensity projection(MIP)and Multiplanner Reconstraction(MPR).Results In 77 cases,49 were aneurysms,19 were AVM,7 were vaso-occlusive,2 were Moya-moya disease.Cerebrovascular was dispayed clearly in VR MIP and MPR.The images acquired with VR were more colorful and spatial than MIP and MPR,but the diagnosis value of MIP and MPR were higher.Conclusion MSCTA is an available noninvasive method in diagnosing the cerebrovascular disease.It could define character and position.MSCTA is an effective method and can be an nalterntive of DSA partially.

Objective To investigate whether there has any difference of gastric and small bowel transit time and completion rates between two capsule endoscopes with different size and weight. Methods Clinical data of patients who had undergone OMOM or MiroCam (smaller and lighter than OMOM) capsule endoscopy were retrospectively studied. Comparison of gastric and small bowel transit time and completion rates were made between the two kinds of capsule endoscopy. Results 1, 448 patients (628 in OMOM group and 820 in MiroCam group) were finally includ-ed. In patients with Crohn's disease or suspected Crohn's disease, gastric transit time of OMOM was significantly longer than that of MiroCam [(53.4 ± 52.6) minutes vs (41.1 ± 47.9) minutes, = 0.022]. In patients with gastroin-testinal bleeding, gastric transit time in OMOM was significantly shorter than that in MiroCam [(42.1 ± 44.8) minutes vs (62.0 ± 78.6) minutes, = 0.016). No significant difference in small bowel transit time or completion rate was found. Conclusions We conclude that the differences of gastric transit time, small bowel transit time and completion rates between the two kinds of capsule endoscopy with different size and weight are not significantly. Whereas, in patients with Crohn's disease or suspected Crohn's disease, gastric transit time of smaller and lighter capsule en-doscopy is shorter in patients with gastrointestinal bleeding, but longer of gastric transit time in smaller and lighter capsule endoscopy.

Objective To develop the dual-beam technology of cyclotron to produce radioactive nuclide, which can increase radiopharmaceuticals output. Methods A new target is installed in cyclotron standby target, and at the same time the tubes and electronic components are fixed to produce radioactive nuclide through dual-beam technology, the product is tested by the dose calibrator. Results The radioactive nuclide can be produced through dual-beam technology and the output is nearly double times about which a single target. Conclusion The productions of cyclotron radioactive isotope are improved by dual-beam technology and meet the clinical needs of PET/CT examination for drugs.

BACKGROUND:Elderly patients with degenerative lumbar degeneration often appear insufficient holding power of pedicle screw in spine surgery, which is prone to occur de-pinning and leads to insecure fixation. How to increase the holding power of screws has become a hot research. OBJECTIVE:To observe the early clinical effect of pedicle screws with cement augmentation for treating lumbar degenerative diseases in elderly patients. METHODS:A total of 65 old patients with lumbar degenerative diseases received a treatment between August 2012 and April 2014, and were divided into two groups according to the treatment strategy:treatment group (n=24;internal fixation of pedicle screws with cement augmentation) and control group (n=41;routine internal fixation of pedicle screws). General conditions of patients in two groups were observed and compared. Visual analog scale (VAS) and Japanese Orthopaedic Association (JOA) score system were used for evaluating the lumbar and back pain, and restoration of neurological function in lower limbs respectively. RESULTS AND CONCLUSION:Al of the patients successful y received the surgery and then were fol owed up from 3 to 20 months. The anterioposterior and lateral X-ray film revealed no loosening, loss, fracture of the screws, and no loss of intervetebral space height was found. There was no significant difference in the blood loss and hospital stay between two groups (P>0.05). JOA at postoperative 3 and 6 months, and VAS score at postoperative 3 months were significantly improved after the treatment of pedicle screws with cement augmentation, when compared to control group (P<0.05). VAS scores showed no difference at 6 months postoperatively in two groups (P>0.05). Pedicle screws with cement augmentation for treating lumbar degenerative diseases have the advantages of improving the screws holding strength, reconstructing the stability of lumbar vertebra and obtaining clinical efficacy on degenerative spine.

Objective To investigate insulin resistance in type 1 diabetes(T1DM)with euglycemic-hyperinsulinemic clamp.Methods Eight cases of newly diagnosed T1DM and 8 cases of newly diagnosed type 2 diabetes(T2DM)were selected.Their insulin sensitivity index(ISI)was evaluated with euglycemic-hyperinsulinemic clamp after 2 week insulin intensive treatment and compared with that of 10 heMthy volunteers(normal control group,NC group).Results Age,BMI,fasting insulin(Fins),fasting C-peptide in the TI DM group were significantly lower than those in the NC group.while waist-to-hip ratio (WHR),systolic blood pressure(SBP),diastolic blood pressure(DBP),TC,TG,LDL-C,HDL-C were not significantly different between the T1DM and NC groups.Age,BMI,WHR,Fins,fasting C-peptide,SBP,TC,TG in the T1DM group were significantly lower than those in the T2DM group.The ISI of the NC,TlDM and T2DM groups were 12.83±1.09,9.95±0.50,3.80±0.20,respectively.There was significant difference among the three groups(P＜0.05).Conclusion The ISI in T1DM Was significantly lower than that in NC group,but higher than that in T2DM.

Objective To compare the diagnostic accuracy of magnifying chromoendoscopy (MCE) and endoscopic ultrasonography (EUS) for preoperative endoscopic assessment of the invasion depth of colorectal laterally spreading tumour(LST).Methods Data of 104 cases of colorectal LST were included.With the final pathological diagnosis as the golden standard,the accuracies of MCE and EUS for preoperative assessment of the invasion depth of colorectal LST were compared.Results The diagnostic accuracies of MCE and EUS for evaluating the invasion depth of LST were 89.4％ (93/104) and 73.1％ (76/104),respectively(P＜0.05).The lesion size and the endoscopist could affect the accuracy of the EUS evaluation (P=0.017,OR=3.561;P=0.035,OR =1.399).The accuracy of EUS seemed to show a downward trend for colorectal LST of larger diameters.Conclusion Both MCE and EUS are effective for evaluating the invasion depth of colorectal LST,but the accuracy of MCE may be higher than that of EUS.Large diameter of the lesion and the doctor's experience inadequacy may be the risk factors for the accuracy of EUS.

Objective:To explore the possibility of constructing tissue-engineered cartilage three-dimensional nanoscaffolds with collagen Ⅱ (COLⅡ), hyaluronic acid (HA) and chondroitin sulfate (CS).Methods:The tissue-engineered cartilage scaffolds were prepared by electrospinning techniques with the mixture COLⅡ-HA-CS solvent, which dissolved by 3-trifluoroethanol-water. The surface topography was observed under electron microscope (SEM). And the diameter of nanofibers, the water absorption rate, contact angle and degradation rate were also detected. Generation 2 rabbit chondrocytes were seeded into the scaffold. The cell survival rate and proliferation were evaluated by Cell Counting Kit-8.Results:When the concentration range of electrospinning was 80-120 mg/ml and the mixing ratio of Col, HA and CS was 6-8∶1∶1-2, the tissue engineered cartilage nanoscaffolds could be successfully prepared. Their diameters were mainly distributed between 126.5±23.3 nm and 374.7±14.1 nm. The scaffolds had satisfactory hydrophilicity and degradability. The chondrocytes could well adhere and proliferate on the scaffold.Conclusions:The COLⅡ-HA-CS tissue-engineered cartilage nanoscaffolds have good physical and biological properties, which suggests its promising application in tissue-engineered cartilage.