Objective:To analyze and compare the dose monitoring and control systems of two types of medical linear accelerator systematically from the view of mechanical and electrical engineering, and establish the method of the quality assurance of the dosimetry system and the solution in the routine maintenance.Methods: To systematically compare and analyze the system of dose monitoring and control for two types of linear accelerators (Precise Elekta and C-series of Varian Medical Systems) from twofold aspects that included machine physics and electric engineering of medical linear accelerators.Results:The monitoring system that took ionization chamber as center was established between connotation of machine physics and concrete realization of electromechanical engineering, and explained the difference and similarity between open type and sealed type of ionization chamber, and the theory that Precise series needn't be serviced by PFN.Conclusion: Based on the analysis of ionization chambers structure of medical linear accelerators on the principle of quality assurance system, proposed dosimetric testing and adjustment method, and provide reference for the establishment of quality assurance system and technical procedures of the maintenance engineering.

Objective To investigate the risk factors of incidence of premature rupture of membranes and provide reference for prevention of premature rupture of membranes.Methods 890 cases of infants and maternal were studied,analyzing and screening the risk factors of premature rupture of membranes by Logistic.Results The single-factor analysis showed that the pregnant women with diabetes,pregnancy-induced hypertension,multiple preg-nancy and vaginifis had certain degree of contact with incidence of premature rupture of membranes.Multivariate Lo-gistic regression analysis showed that the multiple pregnancy and vaginitis were risk factors of incidence of premature rupture of membranes.Conclusion The multiple pregnancy and vaginitis were risk factors of incidence of premature rapture of membranes,assessment and control these risk factors could prevent and reduce the incidence of premature rupture of membranes.

Objective:To discuss the maintenance and testing method, reduce CT machine fault, ensure the quality of CT machine performance, reduce the use of CT machine cost, increase the use value of CT machine,the better service for the masses and treatment.Methods:Using regular maintenance and inspection, specific Toshiba 64 row CT machine each time the content of maintenance and testing content.Results:Regular service and maintenance are the most effective CT machine performance quality guarantee the most basic method, can avoid 30% to 50% of the machine fault, not only greatly reduce the machine hardware damage failure incidence, software programs or data error of failure rates.Conclusion: The regular maintenance and maintenance is hotly debated in recent years the core content of preventive maintenance, periodic testing is an effective guarantee quality of CT machine performance of necessary measures, called on metrology institute and the centers for disease control and coordinated with the hospital, turn the two detection time about half a year, also accord with the national strong inspection requirements so that the rationality of the quality assurance, to avoid most of the repeated testing of national resources waste.

The endotoxemia model was established by intraabdominal injection of endotoxin Coli B. (E. Coli O55B5,8 mg/kg weight)in albino rats. Two hours before administration of endotoxin, the ejiao recovery-pulse decoction was perfused into the stomach tube of the rats in the experimental group (10mg/kg weight), and 12h later, the platelets were counted, kaolin activated partial thromboplastin time (KPTT), prothrombin time (PT) and thrombin time (TT) were measured, and malondialdehyed (MDA) levels in plasma and platelet were determined by thiobarituric acid (TBA) fluorometry. The results demonstrate that the ejiao recovery-pulse decoction could prevent from peripheral platelet dropping, KPTT and TT prolonging and MDA level rising which were caused by endotoxin.

Objective To investigate the early effects of minimally invasive insert in of interlocking intramedullary nails in treatment of femoral shaft fractures. Methods From September 2002 to December 2004, 23 cases of femoral shaft fractures were treated with close reduction and internal fixation using interlocking intramedullary nails. The nail was inserted into the medullary cavity with minimally invasive technique through a small skin incision proximally at the greater trochanter. The mean operative time, volume of transfusion, mean length of hospital stay and early complications after operation were recorded. Results The mean operative time was 90 minutes (ranging from 60 to 150 min) and the mean volume of transfusion was 60 mL (from 0 to 400 mL). There were no early significant complications after operation. The mean hospital duration after operation was 4 days (from 3 to 7 d). Conclusion Minimally invasive insertion of anterograde interlocking nails to treat femoral shaft fractures has advantages of causing little operative trauma, little transfusion, quick rehabilitation and no significant complications after operation

Objective To report the clinical results of the treatment of proximal humeral fractures with a locking proximal humeral plate (LPHP) through a small skin incision on the anterolateral shoulder. Methods In the period from May 2004 to June 2005, 17 cases of proximal humeral fractures were treated in our department. There were 3 Neer two-part fractures, 10 Neer 3-part ones and 4 Neer 4-part ones. Starting from 1.5cm anterior to the acromion, the skin was incised for 6 cm in length and the deltoid muscle was separated along the muscle fibers to expose the fracture fragments. Under direct vision the indirect reduction of the fracture was performed and the fragments were temporarily fixed with K-wires. The LPHP was inserted distally beneath the deltoid muscle and the position between the distal plate and the humeral shaft was adjusted through another small skin incision on the lateral upper arm. 4 locking screws were inserted to the proximal plate to fix the fracture fragments while screws were percutaneously inserted to the distal plate to fix it to the humeral shaft. Results This series experienced a primary wound healing, a mean operation time of (128?35) min, a mean intraoperative blood loss of 65?19 mL, and an average hospitalization of 4 days. A follow-up of mean 6.1 months, ranging from 3 months to 14 months, was performed in 12 cases of the 17 and revealed fracture union in all, with a mean healing time of 15.7 (ranging from 12 to 24) weeks. The final follow-up demonstrated a normal sensation on the lateral arms and a motion range in shoulder abduction of 80?to 150?and flexion of 80?to 160?. Conclusion The treatment of proximal humeral fractures by open reduction and internal fixation with LPHP through a small skin incision on the anterolateral shoulder has the advantages of simplifying operative maneuver, reducing tissue damage, decreasing blood loss, shortening bone healing time and improving functional recovery.

Objective To study dose-response relationship for chromosome translocation and its persistence measured in human lymphocytes exposed to 60Co γ-rays.Methods The chromosome translocations in human peripheral lymphocytes were detected by fluorescence in situ hybridization using 4# and 7# combination of composite whole chromosome-specific DNA probes and Giemsa stain.Results The dose-response relationship for chromosome translocation induced by 60Co γ-rays in vitro could be described by the function:Y=0.0030+0.0134D+0.0165D2.The frequencies of chromosome translocations induced by 0.5 and 2 Gy γ-irradiation did not diminish over time,so it exhibited excellent persistence.Conclusions The results indicate that retrospective dose-reconstruction can be accomplished using chromosome translocation frequency.

Objective It has been unclear how osteopontin, one of metastasis-associated genes, could be regulated in HepG2 cells. The aim of this study was to investigate the effect of protein kinase B(Akt) on the expression of osteopontin in HepG2 cells, and to explore the relationship between Akt and osteopontin expression. Methods HepG2 cells were transfected with constitutively active Akt and dominant negative Akt by lipofectmine, and transfectants were confirmed using Western blot for Akt. Osteopontin expression was detected by Northern blot and Western blot. Results HepG2 cells were successfully transfected with Akt genes including constitutively active Akt and dominant negative Akt, and overexpression of exozegenes Akt could be detected in HepG2 cells by Western blot. Using Northern blot and Western blot, we found that Akt gene regulated osteopontin expression in RNA level and protein level. In serum-free condition, HepG2 cells constitutively expressed low levels of osteopontin. Transfection of constitutively active Akt increased osteopontin mRNA and protein expression. Transfection of dominant negative Akt decreased osteopontin expression.Conclusions The fact that osteopontin gene expression can be regulated by Akt indicates that osteopontin synthesis can be blocked by inactivation of Akt gene and that metastasis of liver cancer might be inhibited by this intervention.

Starting from the syntactic features of Medical English , namely extensive use of nominalization structure, passive voice and complex sentences, the present research attempts to carry out an in-depth study of Medical English translation on the sentence level guided by Nida 's Functional Equivalence Theory . It attempts to combine the translation theory with the translation practice of Medical English, with a view to improving students' translation proficiency and promoting Medical English teaching.

Objectives:To explore a new way in treatment of severe acute pancreatitis(SAP). Methods:From 1995 to 2001,23 patients with SAP proved by clinic and CT were treated, and compared the local artery infusion with intravenous drip on effect,mortality and time of hospitalization. Results:The mortality and time of hospitalization in 12 artery infusion and 11 intravenous drip were (14.4?3.1),(29.3?6.1) days of hospitalization and 8.33%,27.27%(mortality),respectively. Conclusions:The mortality and the time of hospitalization can be reduced by local artery infusion of medicine.