Good patient care requires accurate and comparable laboratory test results. To achieve standardization, a reference system consisting of a hierarchal framework of validated and reliable analytical methods linked by reference materials must be in place. Supported by national and municipal research programs, construction of reference systems has been pursued and progress been made. Candidate reference methods have been set up or developed for some important tests, and the methods have been used in the calibration or evaluation of routine methods, study of commutability of control materials and characterization of reference materials. Phenomenal roles of reference systems are expected in diagnostic reagent manufacturing, internal quality assurance and external quality assessments.

specifications are essential for total quality management in laboratory medicine. A consensus among worldwide professionals has been achieved and a hierarchy of strategies for setting analytical quality specifications has been proposed based on their relevance to medical decision-making. Quality specifications derived from biological variations have been widely accepted because of their objectivity and practicability and have more and more been used in the quality management in laboratory medicine.

Objective To evaluate CT and MRI findings of portal vein aneurysm(PVA)in order to improve its diagnostic accuracy.Methods CT and MRI findings of 9 patients with PVA proved by pathology and direct angiography were reviewed retrospectively.CT scanning was performed in 7 patients,including plain scan (n=2),both plain and enhanced scan (n=5),CT angiography (CTA)(n=3).Plain and enhanced MRI scan were performed in 3 patients.Results (1 )PVA showed a high predilection for old adults.(2 )Of the 9 tumors,4 located in portal vein trunk,2 located in junction of superior mesenteric vein and portal vein trunk,1 located in intrahepat-ic-extrahepatic portal vein,2 located in intra-hepatic portal vein.(3)8 tumors were characterized as well-defined and quasi-circular mass.1 patient occurred portal hypertension,thrombus as the portal vein trunk was oppressed by the tumor.(4)Plain CT showed the mass was slightly higher than pancreas parenchyma density,and uniform with the density of the liver parenchyma.Enhancement scanning showed 4 tumors represented mild or moderate enhancement in portal venous phase except for 1 patient accompany with portal vein thrombus.CTA showed clearly the relationship mass with portal vein,and classified the type of PVA .The 3 lesions represented hypo-intensity on T1 WI and even hyper-intensity on T2 WI.Enhancement scanning showed the tumor was significantly enhancement in portal venous phase on T1 WI.Conclusion CT and MRI have their own advantages in the diagnosis of portal vein aneurysm.Com-bination of CT and MRI could improve the diagnostic accuracy of portal vein aneurysm.

Roles of reference method in clinical biochemistry were introduced.Reference method is an important component of the reference system.Reference methods are primarily used for the establishment and assurance of the traceability of measurement results through calibrating and evaluating routine methods and assigning values to reference materials.Calibration biases and non-specificities of routine methods and the commutability of reference materials are the major issues in the standardization of clinical biochemistry.Standardization also requires availability of commutable reference materials.Reference methods are irreplaceable tools to identify the issues and to characterize reference materials.

Hepatic perfusion parameters play an important role in detecting and diagnosing diffusion diseases of liver. Based on a hemodynamic model. In this study, we described a fast and accurate method to calculate the perfusion parameters. First, we used a dual-input one-compartment kinetics model to illustrate the distribution of the contrast agent concentration among the body. Then, we used the Gaussian function to fit the scatter concentration data of portal vein and aorta, to obtain a liver agent concentration on function of time. Finally, we solved the model parameters by using Levenberg-Marquardt algorithm, and calculated the perfusion parameters. The results showed that the method proposed in this study could calculate the parameters precisely, and had a prosperous future application possibility.
Algorithms ; Contrast Media ; Hemodynamics ; Humans ; Liver ; physiology ; Models, Biological ; Perfusion

OBJECTIVE To find out the actual situations of antibiotics utilization in Respiratory Department of our hospital and provide feedback of improper applications to the clinic,so as to promote proper utilization of antibiotics.METHODS To take samples from clinical cases of 141 samples in Oct to Nov 2006 and fill the forms of the basic information and investigation items of General Hospital of Chinese People′s Armed Police Forces,the cases were finally sorted and summarized with Excel.RESULTS The antibiotics utilization ratio was 96.5%,their combination usage accounted for 70.2%,the etiology detection rate was 61.7%,the improper usage accounted for 34.8%.CONCLUSIONS The situation of antibiotics utilization in our hospital has changed a lot.Hospitals should define regulations and reinforce the management according to The Principle Guidelines of Antibiotics Utilization and actual situations.

OBJECTIVE To find out the situation of antimicrobial usage in cardiac surgical perioperative period.METHODS The use of antimicrobials in cardiac surgical perioperative patients during Jan-Jun 2007,and the data of reasonable use of antibacterial were surveyed and evaluated.RESULTS Of the 276 patients,100.00% of them had received antimicrobials involving 12 kinds,59.78% of them used one kind only and 34.78% used two kinds antibiotics and 5.43% used more three kinds.CONCLUSIONS The use of antimicrobials in cardiac surgical perioperative period is reasonable and scientific.

Objective To compare the efficacy,toxicity and prognosis on treating advanced non-small-cell lung cancer (NSCLC) between using weekly docetaxel (DOC) and using DOC associated with nedaplatin(NDP).Methods 56 cases of NSCLC patients were retrospectively analyzed.Group A included 34 cases who were treated with weekly DOC (35 mg/m2,dl,8).Group B included 22 cases who were treated with DOC associated with NDP (DOC 35 mg/m2,dl,8,NDP 80 mg/m2,d2).One treatment cycle was 21 days.Efficacy,toxicity and prognosis were evaluated after 2 treatment cycles.Results RR of group A was 8.8 ％ (3/34).RR of group B was 27.3 ％ (6/22).DCR of group A was 50.0 ％ (17/34).DCR of group B was 63.6 ％ (14/22).PFS of group A was 2.3 months.PFS of group B was 5.1 months.OS of group A was 8.7 months.OS of group B was 10.5 months.1-year survival rate of group A was 26.5 ％.1-year survival rate of group B was 31.8 ％.The above comparisons were not statistically different (all P ＞ 0.05).In adverse reactions,hematologic toxicity in group B was greater than that in group A (x2 =4.877,P =0.027).Other adverse reactions such as gastrointestinal reactions,fatigue and so on were grade Ⅰ-Ⅱ.Conclusions The treatment of weekly DOC used in advanced NSCLC is safe,effective an low toxicity.There are no significant difference of RR and PFS between single DOC and DOC associated with NDP.

Objective To explore the relationship between the plasma membrane glycoprotein ( PC-1 ) gene and obesity, type 2 diabetes mellitus, insulin resistance in Chinese population. Methods 53 norma1 subjects, 105 simple obesity subjects, 63 type 2 diabetic patients and 114 obesity type 2 diabetics have been genotyped with PCR-RFLP. Results The frequency of PC-1 gene Q allele was 3%, 18%, 4% and 30% in control, obesity subjects, diabetic patients and obesity diabetic individuals, respectively. Compared with control group, the relative risk (RR) in OB group, OBH grop, OBI group, OBL group and OBHIL group was 4. 26,4. 12,7. 36,5. 15 and 9. 70, respectively. Compared with diabetes group, the RR in diabetes with DMOB, diabetes with OBH group, diabetes with OBI group, diabetes with OBL group and diabetes with OBHIL group was 5.23,7. 37,12. 07,8. 53 and 13. 50, respectively. Concluision The frequency of PC-1 gene Q allele were significantly associated with obesity, obesity diabetics and insulin resistance in Chinese. The results suggested that the PC-1 gene Q allele was a potential genetic marker for obesity, type 2 diabetes and insulin resistance.

Objective:To prepare monoclonal antibodies specifically against an immunogenic fragment in ectodomain of prostate-specific membrane antigen ( PSMA ).Methods: An polypeptide immunogenic fragment in the ectodomain of PSMA was predicted by biological information technology,and then it was expressed prokaryotically.BALB/c mice were immunized with the prokar-ytically expressed recombinant polypeptide antigen,to prepare the monoclonal antibodies specifically against an immunogenic fragment in ectodomain of PSMA by hybridoma technology,purification of monoclonal antibody by affinity chromatography,characterization of the monoclonal antibodies by Western blot.The radioimmunoimaging in prostate cancer model was performed by using the labeled McAb.Results:Throught the software analysis,we got the antigen fragment in the ectodomain of PSMA containing 310aa sequences higher specificity, artificially synthesized gene sequence of the region, and constructed a prokaryotic expression vector pET-32a-r-ectodomain-PSMA,by prokaryotic expression we obtained the 50 kD target antigen,after hybridization,the three positive hybridoma cell lines (5E6,4A5 and 4D7) were selected by ELISA using target antigen,the isotypes of 5E6 and 4A5 were IgG2a,the isotypes of 4D7 were IgG1,the titer of three monoclonal antibodies was above 1∶256 000.Western blot results showed that the prepared monoclonal anti-bodies could binding specifically to the antigen in the ectodomain of PSMA.Radioimmunoimaging in prostate cancer animal model results further confirm that the prepared monoclonal antibodies could combinate with the antigen in the ectodomain of PSMA in the animal body, and make the tumor imaging.Conclusion: The prepared monoclonal antibodies can specifically recognizes the PSMA antigen,which laid the foundation for the immunodiagnosis and immunotherapy of prostate cancer.