This article presents the feasibility on application of TiO 2 photocatalysis in drinking water disinfection involving the removal of organic contaminants, inactivation of bacteria and virus. However, the efficacies of TiO 2 photocatalyst in killing of recalcitrant pathogenic protozoans such as Giardia lambia and Cyptosporidium or persistent algae need frurther investigation, and the photocatalytic approach lacks any residual disinfection capacity.

The recent developments in purification and disinfect of drinking water as well as wastewater treatment adopting solar energy-titanium dioxide(TiO2)catalytic technology are introduced in general in the present review. The advantages of this technology are titanium dioxide catalytic agent with strong sunlight absorption in near ultraviolet ray range, lasting catalytic reaction, chemical stable and innocent for human and environment. The oxidizer produced during ray catalytic has strong oxide action that can kill most microorganisms and decompose most organic pollutants. This technology has widespread practical value in the remote areas and rural areas because it does not consume electric energy

Problem-based and student-centered learning patten brings new challenges to the both sides of teaching and learning.Clinical probation is the first step of medical students.The problem-based learning patten is used to clinical probation and achieves good results.It helps to improve medical students' quality and should be applied in China medical education.

Objective To investigate the effects and the mechanism of telmisartan and pyridoxamine on oxidative stress in spontaneously hypertensive rats(SHR).Methods SHRs(male,20 weeks of age) were randomly divided into four groups (n＝ 12 for each):hypertension control (HC) group (2 ml of distilled water),telmisartan group[T,6 mg/(kg · d)],pyridoxamine group[P,200 mg/(kg · d)]and combined group(TP,6 mg/kg telmisartan and 200 mg/kg pyridoxamine per day).Treatments were continued for 16 weeks.The normal control group included 13 WKY rats and received gastric lavage with distilled water.SBP of tail artery was measured during the intervention ervey 2 weeks.The levels of AGEs,SOD and MDA were measured by ELISA,xanthine oxidase and thiobarbituric acid methods after the intervention.Expressiones of NF-κBp65,ERK1 and ERK2 in renal tissue were detected by immunohistochemistry.Expression of RAGE in the renal cortex was investigated by Western blot.Results SOD activity was decreased in the HC group.The levels of AGEs,MDA,RAGE and the activations of NF-κBp65 and ERK1/2 were increased in the HC group (t＝4.53,5.52,2.93,al1 P＜0.05).After the 16 weeks' intervention,SOD activity was elevated in T,P and TP groups compared to that in HC group (P＜0.05).The positive expressiones of NF-κBp65,ERK1 and ERK2 were significantly reduced in T,P and TP groups compared to those in HC group (F＝20.13、148.82、18.70,all P＜0.05).All the positive expressiones of NF-κBp65,ERK 1and ERK2 were lowest in the TP group versus T and P groups (t ＝ 3.58、2.84,P ＜ 0.05).Conclusions Telmisartan and pyridoxamine can alleviate the oxidative stress in spontaneously hypertensive rats,which may result from the blocking effect of Ang Ⅱ,the reduction of AGEs-RAGE and inhibiting the signal pathways of ROS,NF-κBp65 and ROS-ERK1/2.

Objective:To explore influence of monotherapy or combined use of telmisartan and pyridoxamine on aor-tic remodeling in spontaneously hypertensive rats (SHR)and its possible mechanism.Methods:A total of 48 male SHE were randomly and equally divided into hypertension control group,telmisartan group,group,and telmisartan+ group (combined treatment group). Kyoto Wistar rats of the same age and gender were regarded as normal blood pressure control group (normal control group). Thoracic aortic section were examined by related staining af-ter 16 weeks intervention to calculate the ratio of aortic wall thickness to radius of lumen (Tw/Rl),the ratio of wall area to lumen area (W/L),and the area ratio of media elastic fiber/collagen fiber. Concentrations of related en-zymes and receptor etc. of abdominal aortic were measured.Results:Compared with hypertension control group, there was significant rise in ratio of media elastic fiber/collagen fiber area and significant reduction in media collagen fiber/media area ratio in telmisartan group,pyridoxamine monotherapy group and combined treatment group,and there were significant decrease in Tw/Rl [(0.17±0.02)vs. (0.12±0.01)]and W/L [(0.29±0.03)vs. (0.22± 0.02)]ratios in combined treatment group,P <0.05 or <0.01;immunohistochemistry indicated that there were significant reductions in thoracic aortic receptor of advanced glycation end products (RAGE) [(0.24±0.03)vs.(0.17±0.03)]and extracellular signal-regulated kinase 1/2 (p-ERK1/2 )expression [(0.63 ± 0.06)vs. (0.37± 0.04)]in combined treatment group,P <0.05,<0.01. Fluorescence quantitative PCR indicated that medication can significantly reduce nicotinamide adenine dinucleotide phosphate (NADPH)oxidase subunit p47phox mRNA ex-pression (P <0.01 all),especially in combined treatment group (P =0.001).Conclusion:Combined use of telmis-artan and pyridoxamine is superior to the single use of either drug on improving thoracic aortic remodeling in SHR, the mechanism may be related to it reduces local expression of RAGE and p-ERK1/2 ,and inhibits oxidase subunit p47 of NADPH.

Objective Research Dalian region of human papillomavirus infection rate,genotype and age distribution.Determine the area advantage type and high risk population,at the same time to verify that the HPV gene detection method and method of cytological examination of differences.Methods The real-time fluorescence quantitative PCR and gene chip hybridization typing technique in 4177 cases of Clinic Women for HPV genotyping assay.Analysis of genotype HPV infection distribution characteristics,calculation of the age in women at high risk of HPV infection rate.On HPV virus positive patients for cytology test,analysis of different types of infection patient cytology positive rate difference.Results Dalian region women's HPV infection rate was 17.09％ (711/4160),hr-HPV infection rate was 13.73％ (572/4160),low risk type HPV infection rate was 3.36％ (140/4160),the highest infection rate in genotype HPV16 (13.50％),followed by 58,56,33,35,and 68 type.The positive rate of hr-HPV between women of different age groups showed significant difference (P＜ 0.05),the positive rate was the highest in ＜ 30 years old.High risk group of mixed infection of cytology positive rate was higher than that of single hr-HPV infection group and the low risk of infection group.Conclusions Local people infected with HPV advantage of type HPV16.The positive rate of hr-HPV was associated with age,＜ 30 years is the peak of infection of high risk hr-HPV.The mixed infection of cytologically positive rate than other types of infection.

Objective To establish a dot blot hybridization technique for rapid detection of staphylococci and methicillin-resistant staphylococci.Methods Three pairs of primers were designed according to nuc gene of staphylococcus aureus,mecA gene of methicillin-resistance,tuf gene of staphylococci.Specific DNA probes were synthesized by polymerase chain reaction and labeled with biotin.The bacterial DNA inoculated on nitrocellulose filter was hybridized with these probes.The sensitivity and specificity were detected.Results The DNA probes with 270bp,310bp and 370bp were amplified by the three pairs of primers respectively.The probes were specific.Among 50 clinical isolates of staphylococcus aureus tuf and nuc gene were all positive and mecA gene in 22 isolates were positive.Positive rate of tuf,nuc and mecA gene in 30 staphylococcus epidermidis were 100%,0 and 30% (9/30) respectively.No hybridization in other non-staphylococci occurred.The established method could detect as low as 1ng of bacterial DNA.Conclusion The dot blot hybridization is of high value in rapid,effective identification of methicillin-resistant staphylococci.

Objective To explore the surgical extent and to improve the surgical techniques of the Piver class Ⅲ hysterectomy on invasivc cervical cancer,so as to reduce the urinary tract complications,shorten the surgical duration,decrease the hemorrhage and blood transfusion.Methods The study group,196 cases with stages Ⅰ b and Ⅱ a carcinoma of the cervix underwent the modified Piver class Ⅲ hysterectomy from June 2000 to May 2005.The control group,176 cases of the same stages underwent the Pivet class Ⅲ hysterectomy between June 1994 and May 1999.The modified Piver class Ⅲ hysterectomy mainly include the surgical extent and some surgical techniques as follows.The cervicovesical and vesicovaginal space are separated with assistance of electrotome.Half of the uterosacral ligaments are removed with electrotome.The tunnel of the ureters is separated and penetrated or not. The anterior leaf of the cervicovesical ligaments is removed and the uterine artery are removed at the same time.while the ureter branch from the uterine artery are preserved.When the ureters aIe drawn to the lateral side of the body with an "S" hook and the urocyst lateral recessus are expanded.the cardinal ligaments can be exposed and be removed of 3/4.But part of the inferior of these ligaments should be preserved.The paracolpium are resected about 2 cm.2-3 cm tissue of the vagina is removed.Results Compare with the control group,the urinary tract complications of the study group were significantly reduced(51.1%versus 23.0%,P<0.01).There were a shorter surgical duration[(132±20)min],less of the hemorrhage[(322±100) ml]and blood transfusion[(154±79)ml] in the study group than those in the control group(all P<0.05).While,there was no significant difference at the survival rates of 5 years between the two groups (87.8% versus 88.6%.P=0.793).Conclusion The modified Piver class Ⅲ hysterectomy is effective and applicable for patients with cervical cancer.

Objective To analyze the correlation between emphysema extent measured by high resolution computed tomography (HRCT) and pulmonary function tests, symptom score in patients with chronic obstructive pulmonary disease ( COPD ) , and to study the value of HRCT in the emphysema quantification in the clinical evaluation of COPD patients. Methods 78 patients with stable COPD were recruited to take the HRCT scan , and emphysema extent was qualified by measuring the proportion of low attenuation area in the whole lung (LAA%). Correlations between LAA% and indices of pulmonary function test, bronchial dilation test, mMRC scale, CAT score and six minutes walking distance (6MWD) were assessed. Results LAA% was negatively correlated with FEV1/FVC and DLCO%pred, and the correlation coefficients were -0.759 and -0.589 (P <0.01), respectively. LAA% was positively related to mMRC score (r = 0.342, P < 0.01), and negatively asso-ciated with 6MWD (r = -0.365,P< 0.01). There was no association between LAA% and indices of bronchodila-tion test (⊿FVC, ⊿FVC%, ⊿FEV1, ⊿FEV1%) (P > 0.05). Conclusions The severity of emphysema measured by HRCT is well correlated with the clinical symptoms , pulmonary function tests and exercise capacity in COPD patients. It can be used to diagnose emphysema early and to evaluate the severity of the disease com-prehensively. Thus, the risk factors of COPD can be controlled and the prognosis of the patients can be im-proved.

Objective: To observe the effect of pyridoxamine and telmisartan on the indexes of myocardial remodeling in spontaneous hypertensive rats (SHR). Methods: A total of 48 male SHR at 22 weeks of age were randomly divided into 4 groups:①Hypertension (H) control group, the rats received distilled water 2 ml/d,②telmisartan (T) group, the rats received telmisartan 6 mg/(kg.d),③pyridoxamine (P) group, the rats received pyridoxamine 200 mg/(kg.d),④Combination (TP) group, the rats received both telmisartan and pyridoxamine. All animals were treated for 16 weeks and the systolic blood pressure (SBP) was measured before and after treatment. After treatment, the serum levels of nitric oxide (NO) and super oxide dismutase (SOD) were examined by chemiluminescent method, advanced glycation end-products (AGEs) was detected by ELISA, left ventricular weight index and collagen volume fraction (CVF) in myocardial tissue were calculated, the mRNA expression of myocardial receptor of advanced glycation end products (RAGE) was evaluated by real time RT-PCR. Results: Compared with H group, SBP levels were decreased in T and TP groups,P<0.01, while SBP in P group stayed similar,P>0.05. Compared with H group, the serum levels of NO and SOD were increased in T, P and TP groups,P<0.01; while compared with T group and P group, the levels of NO and SOD were further increased in TP group,P<0.05. Compared with H group, left ventricular weight index and CVF were decreased in T, P and TP groups,P<0.01; while compared with T group and P group, left ventricular weight index and CVF were further decreased in TP group,P<0.05. Pyridoxamine and telmisartan had the coordinative effect on left ventricular weight index and CVF, P<0.05. The serum levels of AGEs were lower in T group (5.99 ± 0.51) mg/L, P group (5.57 ± 0.91) mg/L and TP group (5.24 ± 0.63) mg/L than that in H group, (6.71 ± 0.50) mg/L,P<0.01; while compared with T group and P group, AGEs was further decreased in TP group,P<0.05. The mRNA expressions of RAGE were reduced in T group (0.035 ± 0.010), P group (0.036 ± 0.005) and TP group (0.024 ± 0.007) than that in H group (0.053 ± 0.010),P <0.01; while compared with T group and P group, the mRNA of RAGE was further reduced in TP group, P<0.05. Conclusion: Pyridoxamine could improve the oxidative stress and the indexes of myocardial remodeling independently from decreasing blood pressure in SHR. Combined intervention of P and T may break the coordination systems between AGEs-RAGE and renin-angiotensin, therefore further improve the indexes of myocardial remodeling in SHR.