Objective To explore the feasibility of DSCT dual-energy technique in pulmonary mass lesions.Methods A total of 100 patients with pulmonary masses underwent conventional plain CT scan and dual-energy enhanced CT scan.The virtual non-contrast (VNC) images were obtained at post-processing workstation.The mean CT value,enhancement value,signal to noise ratio (SNR),image quality and radiation dose of pulmonary masses were compared between the two scan techniques using F or t test and the detectability of lesions was compared using Wilcoxon test. Results There was no statistically significant difference among VNC ( A ) ( 32.89 ± 12.58 ) HU,VNC (S) ( 30.86 ± 9.60) HU and conventional plain images (35.89 ± 9.99 ) HU in mean CT value of mass ( F =2.08,P ＞ 0.05 ).There was statistically significant difference among VNC ( A ) ( 3.29 ± 1.45 ),VNC (S) ( 3.93 ± 1.49 ) and conventional plain image (4.61 ± 1.50) in SNR ( F =6.01,P ＜ 0.05 ),which of conventional plain scan was higher than that of VNC.The enhancement value of mass in conventional enhanced scan(60.74 ± 13.9)HU and distribution of iodine from VNC (A) ( 58.26 ± 31.99 ) HU was no statistically significant difference ( t =0.48,P ＞ 0.05 ),but there was a significant difference between conventional enhanced scan (56.51 ± 17.94 ) HU and distribution of iodine from VNC (S) (52.65 ± 16.78 ) HU (t =4.45,P ＜ 0.05 ).There was no statistically significant difference among conventional plain scan ( 4.69 ± 0.06 ) and VN C ( A ) ( 4.60 ± 0.09 ),VNC (S)(4.61 ±0.11 ) in image quality at mediastinal window ( F =3.014,P ＞ 0.05 ).The appearance,size,internal features of mass (such as necrosis,calcification and cavity) were showed the same in conventional plain scan,VNC (A) and VNC (S).Of 41 patients with hilar mass,18 patients were found to have lobular and segmental perfusion decrease or defect. Perfusion defect area was found in 59 patients with peripheral lung mass. The radiation dose of dual-energy enhanced scan was lower than that of conventional scan.Conclusion The virtual non-contrast,distribution of iodine and pulmonary virtual perfusion images can be obtained by DSCT dual-energy technique in one scan,which has a potential clinical value in the thorax.

Objective To explore the effects of ligustrazine (TMP) on acute drug -induced free radical for-mation in guinea pig cochlear ,and to explore possible mechanisms of TMP on gentamycin(GM)-induced ototoxici-ty .Methods Sixty guinea pigs were randomly divided into four groups ,control group ,GM group ,TMP group and TMP+GM group .GM group were injected with GM 120 mg/kg per day .TMP group were injected with TMP 40 mg/kg per day .TMP+GM group were injected with GM and TMP at the same dosage .Control group were injected with normal saline .All groups were injected for consecutive 10 days .Before injection and one day after the last injec-tion ,ABR thresholds were measured .Biochemical assays of Superoxide Dismutase (SOD1 ,SOD2 ,T -SOD) activity and ma1ondia1dehyde(MDA) content in guinea pig cochlear were detected by TBA .Results After the injection , ABR thresholds in GM group were significantly increased compared with those of in control group (P<0 .01) ,with significant difference between GM +TMP and GM group(P<0 .01) .Before and after the experiment ,ABR thresholds in control group were almost unchanged(P>0 .05) .SOD activity was significantly decreased while MDA content was increased in cochlear tissues after GM injection (P<0 .05) .Co -treatment with TMP evidently enhanced SOD activity and decreased MDA content (P<0 .05) .Conclusion TMP may enhance SOD activity and prevent lipid per-oxidation ,thus alleviate GM ototoxicity ,and improve auditory function .

Objective To investigate the effects of preconditioning with 3-nitropropionie acid on myocardial apoptosis induced by ischemia-reperfusion injury.Method Twenty-four rabbits were randomly divided into control group(group C,n=8),precondition group(group 3-NPA,n=8)and 5-HD group(group 5-HD,n=8).The group 5-HD was treated intravenously with 5 mg·kg-1 5-HD(ATP-sensitive potassium channels blocker),group C and group 3-NPA received normal saline instead of 5-HD.Ten minutes later,5-HD group and 3-NPA group were injected with 3-NPA(3 mg·kg-1)and the group C was injected with normal saline.Twenty-four hours later,the left anterior descending coronary artery was ligated for 30 min and then unclamped for 120 min to estabhsh ischemi-a-reperfitsion injury model.After reperfusion,the infarct sizes of ventricular myocardium,apoptotic myocardial cells and the expressions of Bcl-2 and Bax protein were measured.Results Infarct sizes and apoptotic myocardial cells in group 3-NPA were less than those in the others(P＜0.01).The expressions of Bcl-2 in group 3-NPA.in-creased as compared with group C(P＜0.05)and group 5-HD(P＜0.05),whereas the expressions of Bax in group 3-NPA decreased as compared with group C(P＜0.05)and group 5-HD(P＜0.05).Conclusions Preconditioning with 3-nitmpropionie acid reduces myocardial apoptosis induced by isehemia-reporfusion injury which is attributed to the opening of mitochondrial KATP channels.

Objective To study the effect of conditioned media for rat bone marrow mesenchymal stem cells (BMSCs-CM) on palmitic acid (PA)-induced insulin resistance (IR) in HepG2 cells and its underlying molecular mechanisms.Methods HepG2 cells were treated with or without BMSCs-CM and L-DMEM in the presence or absence of PA.Glucose utilization in HepG2 cells were detected with PAS,glucose and glycogen measurements.Western blotting was used to assess the expression of phospho-insulin receptor substrate (p-IRS),phosphatidylinositol 3-kinase (PI3 K) and p-AKT.Results (1) Incubation of HepG2 cells with 0.25 mmol/L PA for 24 hours significantly increased the glucose concentration and decreased the glycogen content (P ＜ 0.05) in the media.(2) Treatment with BMSCs-CM significantly ameliorated the glucose and glycogen alteration in cells pretreated with PA (P ＜ 0.05),however,no obvious effect of BMSCs-CM on the cell glucose and glycogen production.(3) BMSCs-CM treatment also increased protein expression of p-IRS,PI3K and p-AKT in PA incubated HapG2 cells (P＜ 0.05).The effect of BMSCs-CM on PI3K and p-AKT expression could be mimicked upon addition of 740Y-P,a PI3K agonist,but abolished by LY294002,a PI3K specific inhibitor.Conclusions BMSCs-CM could improve the insulin sensitivity in HepG2 cells pretreated with PA through upregulation of insulin signaling component expression.

Objective To investigate the influences of imatinib on Survivin gene expression in bcr-abl-transformed leukemia cells.Methods Firstly,PCR and Western blot were carried out to detected Survivin expression with imatinib treatment in 32Dcl3 and 32D-bcr-abl cell lines.Then the luciferase reporter plasmids containing human Survivin promoter as well as its deletion and site-directed mutation were constructed to identify the essential responsive elements for suppressing Survivin promoter activity by imatinib.Chromatin immunoprecipitation was performed to confirm the binding of c-myc to Survivin promoter.10058-F4,a small molecule c-myc inhibitor,was used to disrupt c-myc activity and evaluate its anti-leukemic effect combined with imatinib.Results Both of mRNA and protein level of Survivin in bcr-abl-transformed cells were downregulated upon imatinib treatment.The decrease of Survivin expression was controlled at the transcriptional level through a mechanism in which imatinib repressed survivin promoter activity by disturbing the interaction between c-myc and E-box elements.Interruption of c-myc activity by 10058-F4 exerted an anti-leukemia effect with enhancing the sensibility of K562/G01 cells to imatinib.Conclusion Imatinib down-regulates Survivin expression through c-myc-mediated transcription and interference with c-myc might be a potential utility for treatment of imatinib resistant leukemia.

Abstrac:Objective To analyze the efficacy and safety of medpor-coated tear drain in lacrimal bypass surgery without skin incision. Methods The data of 7 patients(7 eyes) who underwent no skin incision of lacrimal bypass surgery with medpor-coated tear drain were ret-rospective reviewed. The operation result and complications were observed. Results All patients were followed up for 5~17 months. Com-plete or significant improvement of epiphora was achieved in 5 cases at the last follow-up. Complications included conjunctival granulation hy-perplasia (3 eyes),nasal mucosal granulation hyperplasia (2 eyes),and discomfort (4 eyes). Conclusion The lacrimal bypass surgery with medpor-coated tear drain could be expected to improve epiphora of refractory lacrimal obstruction. The main complications are granulation hyperplasia and discomfort.

Objective To investigate the relationship between continuous hyperglycemia and the progression of early acute pancreatitis (AP) Methods Five hundred and twelve AP patients were included in this study, in which 418 patients were mild acute pancreatitis (MAP) and 94 were severe acute pancretitis (SAP) Fasting blood sugar was determined and APACHE Ⅱ score was calculated on admission, 2nd and 3rd day of hospitalization respectively Serum tumor necrosis factor (TNF?) and C reaction protein (CRP) levels were determined on the 2nd day of hospitalization Results The incidence of hyperglycemia was higher in SAP patients than that in MAP patients (74 5% vs 25 8%, P =0 001) In SAP, APACHE Ⅱ score in continuous hyperglycemia group (CHG) was significantly higher than that of non continuous hyperglycemia group (NCHG) on admission, 2nd and 3rd day of hospitalization respectively (13?4 vs 11?3, P =0 017; 13?4 vs 11?3, P =0 010; 14?4 vs 10?4, P =0 010, respectively) Continuous hyperglycemia was related to the severity of SAP ( ? 2=7 77, P =0 005) Moreover, serum TNF? and CRP levels of the CHG were also markedly higher than that of NCHG (20?14 vs 14?11, P =0 019; 123?81 vs 93?55, P =0 036, respectively) Conclusion Continuous hyperglycemia might be a risk factor for the aggravation of early acute pancreatitis

BACKGROUND: Previous studies have demonstrated that LRP16 is an estrogen-responsive gene. Its expression level is strongly associated with the proliferation and invasive growth of human breast cancer cells.OBJECTIVE: To construct a LRP16 targeting vector and screen mouse embryonic stem cell clones with homolougous recombination of an inactive LRP16 gene.DESIGN: Constructing an inserting inactivation target by inserting SA-RIES-β geo expression cassette.SETTING: Bioregulatory Laboratory of the Third Medical Department of Kyushu University in Japan and Department of Molecular Biology, General Hospital of Chinese PLA.MATERIALS: The materials used here were mainly provided by the Bioregulatory Laboratory, the Third Medical Department of Kyushu University in Japan. The mouse genomic library in pBeloBAC11 Vector was purchased from lnvitrogen Corp. The competent TopF10 was purchased from Beijing Tiangen Biotech Corp. pcDNA3.1(+) vector was kept in our laboratory. Mouse ES cells were provided by Kyushu University.METHODS: The experiment was performed in Kyushu University and Department of Molecular Biology of PLA General Hospital from November 2004 to May 2005. Targeting sequence of LRP16 gene was obtained from 129 mouse genomic Bacterial Artificial Chromosomes library based on polymerase chain reaction (PCR) screening. The SA-RIES-β geo fragment was inserted within LRP16 fifth exon to inactivate LRP16. ES cells were screened with G418 and the homologously recombinant clone was identified by Southern blot analysis.MAIN OUTCOME MEASURES: Clones with homologous recombination.RESULTS: The LRP16 fragment including exon 5 to 11 was subcloned into the pBluescript SK Ⅱvector. Restriction map demonstrated that the SA-IRES-β geo fragment was correctly inserted into the LRP16 fifth exon. Southern blot results showed that there was an ES clone with targeting sequence homologously inserted.CONCLUSION: A LRP16 gene targeting vector is constructed and a homologous recombinant is obtained.

Objective To investigate the risk factors for conversion of laparoscopic cholecystectomy (LC) to laparotomy.Methods In 1020 LC patients,36 patients with conversion of LC to laparotomy were chosen as the case group,108 patients with successful LC were chosen as the control group.Univariate analysis and Logistic multivariate regression model were used to analyze the risk factors for conversion of LC to laparotomy.Results Age ＞ 65 years (0R=3.234,95％ CI:0.532-6.853),course of disease ＞ 72h (OR =2.342,95％ CI:0.568 ～ 5.656),history of upper abdominal operation (OR =2.453,95％ CI:0.345-7.453),thickness of gallbladder wall ≥ 6 mm (OR =2.453,95％ CI:0.453-6.343),white bloodcell count ＞ 15.0 × 109/L (OR =4.532,95％ CI:0.535-8.329) were risk factors for conversion of LC to laparotomy.Conclusion Preoperative comprehensive evaluation the risk factors and selecting suitable program have important clinical significant in reducing the rate of conversion LC to laparotomy.

Prominent problems of clinical teaching in Tibet University school of medicine were analyzed and countermeasures were proposed from aspects of management system construction, facul-ty construction, curriculum construction, base construction and quality evaluation system construction. The aim was to increase students' opportunity, enhance students' learning interest and improve stu-dents' ability of analysis and problem solving so as to improve the practical effects of clinical teaching. All countermeasures taken above laid the foundation for future clinical work and provided help for clinical medical personnel in Tibetan border areas.