Objective To investigate the prevalence of benign prostatic hyperplasia (BPH) in Beijing. Methods A cross-sectional study was performed at Beijing communities in men aged over 50 years. The International Prostate Symptom Score (IPSS) questionnaire was used to evaluate the symptoms. Transabdominal ultrasonography was used to measure prostate size and the residual urine volume(RUV). Uroflowmetry was performed to record the maximum flow(Q_(max)). One-way ANOVA was used to analysis the differences. Results 1644 subjects were enrolled and the mean age was 64. 5 years (range 50 - 93 years). The mean IPSS, prostate weight andQ_(max) were 9. 9±8. 2, (30. 8± 19.4) and (14. 7 ± 7. 5)ml/s, respectively. They had correlation with age (r=0. 388,0. 262, - 0.371). The prevalence of moderate-severe lower urinary tract symptoms (LUTS) was 50. 8% (835/1644). Prostate volume was greater than 20 ml in 69. 7%(1146/1644) of the subjects.Q_(max) was less than 15 ml/s in 53. 8% (883/1642) of the subjects. Conclusions In men age over 50 years in Beijing, there is positive correlation between LUTS, prostate size and age, and negative correlation between Q_(max) and age. The prevalence of BPH, defined as IPSS greater than 7, maxium flow rate less than 15 ml/s and prostate size greater than 20 ml, is 26. 8%(441/1644).

The exploration of drug toxicity and mechanisms is a vital component in ensuring the safe use of drugs in clinical practice, as this topic has attracted widespread concern. The intestinal flora holds great significance for drug metabolism, efficacy and mechanism, and is an instrumental metabolic organ that facilitates material information transfer and biotransformation. However, an increasing number of studies have shown that intestinal bacteria are closely related to the toxicity of specific drugs. On the one hand, drugs are transformed into toxic metabolites under the influence of intestinal bacteria, thus inducing direct drug toxicity. On the other hand, the composition and function of the intestinal flora are altered under drug influence, resulting in disruption of endogenous metabolic pathways. Consequently, this disruption compromises the intestinal barrier and affects other organs, leading to indirect drug toxicity. This review meticulously compiles recent examples of drug toxicity attributed to intestinal bacteria, explores in depth the contention that metabolic enzymes of gut microbiota may be of great influence on oral drug toxicity, and outlines prospective avenues for future research on gut microbiota and drug toxicity and mechanisms. This not only provides novel perspectives for the judicious clinical utilization of drugs but also offers insights for the safety assessment of innovative pharmaceuticals.

Objective To investigate the curative effect of RevoLix 2 micron continuous wave laser va-poresection for treatment of elderly and high risk benign prostatic hyperplasia patients. Methods Clinical data of 36 benign prostatic hyperplasia patients with medical complications aging 70 -82 years were retro-spectively analyzed. Operations were done after their complications were controlled. The RevoLix 2 μm laser system with output power of 70 W was used, and normal saline was used as rinse solution. Operations were started after positions of seminal colliculns and distances to neck of bladder were confirmed. Results Oper-ation time varied from 65 to 135 rain with a mean time of (83.6±10. 6) rain. Occasional venous hemor-rhage occurred during operation but no arterial hemorrhage was observed. No blood transfusion necessitated and no TURP syndrome was observed. Catheter was removed 2-4 days after operation. All the patients could urinate freely. No urinary incontinence was found during follow-up except 2 patients with temporary urinary incontinence. A 3-6 months follow-up showed that IPSS decreased from 24. 26 ±2. 70 to 8.47±4. 32, QOL dropped from 4. 51±0. 56 to 1.34 ± 0. 53, and Qmax increased from (6. 37 ± 1.31) mL/s to (17.24± 2. 32) mL/s. Conclusions RevoLix 2 micron continuous wave laser vaporesection is a safe and effective method with less trauma and fast recovery for treating elderly and high risk benign prostatic hyperplasia pa-tients.

Objective To investigate the prevalence of sexual dysfunction in aged men and associated risk factors in Beijing. Methods A cross-sectional study was performed in communities of Beijing involved 1656 men aged over 50 years.The International Index of Erectile Function-5 (IIEF-5),Brief Male Sexual Function Inventory for Urology ( O'Leary 1995 ) and the International Prostate Symptom Score (IPSS)questionnaires was recorded.The body mass index (BMI),prostate size was measured.The survey was conducted to make sure if the patients had diabetes,high blood pressure,hyperlipidemia,cerebrovascular history,and smoking and drinking situation.Pearson's X2 test and unconditional logistic regression were used to investigate the factors associated with sexual dysfunction. Results 1644 subjects were enrolled.The incidence of ED,reduction of sexual desire and defective ejaculation was 90.45％,60.04％ and 38.81％ respectively,and significantly different according to age ( P ＜ O.05 ). Age was positively correlated with ED (3 =0.12,P＜0.05),reduction of sexual desire (β =0.10,P＜0.05) and defective ejaculation (β =0.10,P ＜ 0.05 ) ; ED was significantly associated with BMI (β =0.07,P ＜ 0.05 ).Hypertension and prostate size were risk factors for reduction of sexual desire and defective ejaculation; There was correlation between drinking and defective ejaculation ( β =- O.31,P ＜ 0.05 ). Conelusions Compared with high prevalence of ED and lower sexual desire,the incidence of defective ejaculation were lower; this may reflect the sexual activities of aged male were more active compared with the less success of really erection.The prevalence of ED,reduction of sexual desire or defective ejaculation increased with age.BMI was the risk factor for ED.Enlarged prostate and hypertension was associated with reduction of sexual desire,and drinking was the risk factor for defective ejaculation.

Objective To evaluate the feasibility of using pure laparoscopic radical nephrectomy and thrombectomy to treat renal tumor with renal vein and vena caval thrombus. Methods Two ca-ses o{ right renal tumor with renal vein and vena caval thrombus were reported. Contrast-enchanced CT showed renal tumor extended into renal vein and vena cava in 1 case, and filling defect was found in right renal vein and extended to vena cava in the other. Both patients received pure laparoscopic ra-dical nephrectomy and thrombectomy through retroperitoneal approach. Four trocars were placed du-ring the operation, and the renal artery was dissected before the vena cava was mobilized circumferen-tially above and below the renal vein, a faparoscopic vessel blockage clamp was used to partly occlude the vena cava containing the thrombus. The vena cava was repaired after the intact tumor thrombus was extracted. Results The tumor thrombus extended 0.3 cm and 1.0 cm above the renal vein, re-spectively. Both patients were discharged 5 d after operation. Pathological examinations showed that tumors were epithelioid renal angiomyolipoma and grade Ⅰ-Ⅱ clear cell carcinoma separately. Both patients were free of local recurrence and metastasis 5 months after operation. Conclusion Pure la- paroscopic radical nephrectomy and thrombectomy for renal tumor with vena caval and renal vein thrombus is feasible in carefully selected patients.

Objective To investigate the changes of target during fractionated radiotherapy for e-sophageal cancer, and to assess their impact on the implementation of radiotherapy. Methods Fourteen pa-tients with unresectable esophageal cancer were enrolled to receive full course conformal radiotherapy. CT scans were performed after every ten fractions. New targets (GTV) were delineated on repeated CT scans. Then the pretreatment radiotherapy plans were copied to the new targets to investigate the conformity between the new GTV and the plans. Results The majority of the GTVs decreased with the increasing fractions dur-ing radiotherapy. However, GTVs of 35.7% (5/14) patients increased by 2.0%-37.7% at the tenth frac-tion. The PTVs covered by 95% isodose curve at the time of pretreatment,tenth fraction,twentieth fraction and thirtieth fraction were 97.81%±1.53%, 91.95%±5.25%, 94.27%±4.23% and 94.03%±6.45%, respectively. Moreover, at tenth, twentieth and thirtieth fraction, there were 6,5, and 4 patients whose PTVs covered by 95% isodose curve were below 95%, respectively. Conclusions There are signifi-cant target changes during fractionated radiotherapy for esophageal cancer, which may result in uncertainties of radiotherapy implementation.

Objective: To study the influence of negative electrets on apoptosis of fibroblast cells and to probe its mechanism. Methods: Fibroblast cell were treated with -300, -500 and -1 000V PTFE electrets for 24, 48 and 72 h, respectively, and the influence of negative electrets on cell apoptosis was studied by means of flow cytometry and transmission electron microscope. Results: Compared with control group, apoptosis cells increased from 0.5% to 10% (some even to 15%) after 24，48 and 72 h action of -300, -500 and -1 000 V electrets. After action of -500 V PTFE electrets for 48-72 h, fibroblast cells showed characteristic morphological features of apoptosis. These features included chromatin aggregation, nuclear and cytoplasmic condensation and partition of cytoplasm and nucleus into membrane bound-vesicles (apoptotic bodies). The effect of negative electrets on apoptosis was in proportion to the time and electric field intensity. Conclusion: Negative electrets can enhance apoptosis of fibroblast cells.

A region of the D17S30(pYNZ22) locus was amplified in DNA from 120 unrelated chinese individuals was carried out. The amplified products were analysed by mini-polyacrylamide gel electrophoresis followed by silver stain. 11 alleles, ranging from 170bp to 870bp in size and from 0. 4 % to 30. 4 % in frequency, was detected. The heterozygosity was 73%, Dp value was 0.938. The family study showed that the Amp-FLP in pYNZ22 locus is inherited according to the Mendelian law. The correct genotyping results can be obtained from very little amount of biological material, such as mixed stains, blood stains, single hair and saliva.

Objective To study the structure of class 1 integrons in 90 strains of Pseudomonas aeruginosa isolated during two periods of 1992-1996 and 2003-2005,and to get information about the structure changing of class 1 integrons by comparing their structures in two different periods.Methods Routine PCR and long PCR were performed to amplify the class 1 integrons and the gene cassettes they carried, followed with sequencing and blast via GenBank.Results Thirteen out of 41 strians ioslated during the period of 1992-1996 were positive on class 1 intergrons.Long PCR showed that the class 1 integron was 1868 bp in length and contained 2 resistance genes averagely.Six types of resistance genes of qacEA1 (n=6), sull (n=14),aadA1 (n=2),aadB (n=1),PSE-1 (n=2) and tetA (n=1) were found in these integrons, which consisted of 5 patterns of resistance cassette arrangements.Nineteen strains were proved to carry class 1 integrons in 49 isolates from 2003-2005.The mean DNA sequence length of them was 3383 bp with 3.6 resistant genes in averagely,10 types of resistance genes,qacEA1 (n=18),sull (n=25),aadA1 (n=6), aadB (n=7),aacA4 (n=2),PSE-1 (n=3),VEB-1 (n=4),OXA10 (n=1),cm1 A (n=1) and tetA (n =2),were identified in these integrons,which were composed of 9 patterns of resistance cassette arrangements.Conclusion In terms of produce length and resistance cassettes carried in the integrons, greater complexity is found in the structure of class 1 integrons in strains isolated during 2003-2005 than those during 1992-1996.

The polymorphisms of minisatellite p33.6 (D1S111) locus were typed rapidly and accurately us- ing polymerase chain reaction (PCR). The amplified fragments were analyzed by mini- polyacrylamide gel electrophoresis followed by silver stain. The distribution of allele frequencies among 100 unrelated Chinese is reported. 14 alleles, containing 9 to 22 repeat units, had been detected with a heterozygosity of 76%. The allele frenquencies were from 0.5 %to 35.5 %. The size of amplified fragments ranged from 435 bp to 925bp. The discrimination power of p33.6 locus was 0. 916. The Amp --FLP was inherited according to the Mendelian Law. The results showed that the polymorphisms of p33.6 locus can be used for individual identification and paternity test.