In recent years, researches on cells, animals, and human beings have found that the carcinogenic mechanism of environmental carcinogen benzo (a) pyrene〔B(a)P〕can reduce methyla?tion of the whole genes, increase the tumor suppressor gene methylation and reduce the gene methyla?tion of proto-oncogene, in addition to the genetic toxicity. It can also cause changes in small RNA expression, the increase of long-chain non-coded RNA expression and imbalance in histone phosphor?ylation expressions. These changes can cause abnormalities in gene expression and chromosome structure and instability, directly leading to cancer. These changes can also cause the corresponding changes of genetic toxicity, such as gene mutation, abnormal genetic damage repair, increas of cell apoptosis and cell cycle arrest. All these are considered to be potential epigenetic mechanisms of B(a)P. Existing researches have provided the scientific basis for the mechanism of and prevention counter?measures for environment-related diseases and vocational diseases caused by B(a)P.

Objective To explore the value of ultrasound in assessment of treatment effect of diffuse toxic goiter.Methods 80 diffuse toxic goiter patients with 131I therapy were selected as research subjects.Before and after treatment,the serum thyroid hormone levels were detected and thyroids were checked by ultrasound.Results Before and after treatment,the FT3 levels were positively correlated with blood flow area ratio and flow grade (r =0.472,0.593,all P ＜ 0.05).After treatment,the thyroid weight,peak systolic velocity(PSV) and end diastolic velocity (EDV) [(12.89 ± 7.86) g,(32.24 ± 21.85) cm/s,(12.36 ± 19.22) cm/s] were significantly lower than those of before treatment [(30.12 ± 17.24) g,(68.58 ± 34.25) cm/s,(28.03 ± 21.24) cm/s] (t =11.265,4.762,3.672,all P ＜ 0.05).Before and after treatment,the RI and PI showed no significant difference(all P ＞ 0.05).The difference of thyroid blood flow grade before and after treatment was statistically significant (x2 =98.959,P =0.000),the proportion of flow grade class Ⅲ before treatment was higher(80.0％),while the proportion of flow grade class Ⅰ after treatment was higher(60.0％).After treatment,the FT3 and FT4 levels [(6.88 ± 4.14)pmol/L,(17.23 ± 7.35)pmol/L]were significantly lower than those of before treatment [(18.79 ± 6.45) pmol/L,(56.47 ± 22.97) pmol/L] (t =17.243,13.254,all P ＜ 0.05).The TSH level [(11.52 ± 8.27) mU/L] was significantly higher than that of before treatment[(0.01 ± 0.00)] mU/L (t =3.365,P ＜ 0.05).After treatment,the thyroid weight,PSV and EDV of cure group[(9.34 ±2.36) g,(20.13 ± 8.59) cm/s,(9.13 ± 5.34cmn/s)] were lower than those of non-cure group [(18.78 ± 8.76) g,(52.32 ± 13.24) cm/s,(17.24 ± 8.34crn/s)] (t =9.143,8.793,5.232,all P ＜ 0.05).The differences of RI and PI in the cure group and non-cure group were not statistically significant (all P ＞ 0.05).Conclusion Ultrasound has a better role in the evaluation effect of 131I therapy for diffuse toxic goiter.

Objective To analyze the correlation of acute pancreatitis with hyperlipemia and C reactive pro-tein. Methods 42 patients with acute pancreatitis with hyperlipemia were divided into two groups of SAP group and MAP group under the diagnostic code. The blood fat and CRP were compared between the two groups, also the scores of APACHE Ⅱ , Ranson and CT were measured. Results The CRP and TG in group SAP compared with those in group MAP had significant difference(P<0.01),but the CHOL has no-difference;the scores of APACHEⅡ , Ranson and CT after control lipid in 42 patients were significantly' different( P < 0.05). Conclusion Hyperlipe-mia is one risk factors of the AP;combined with the CRP, it can be one evaluating index of the severity.

Objective To study the influence of partial internal sphincterotomy on the postoperative pain after cutting seton treatment in patients with perianal infection. Methods A controlled study was carried out on 40 cases of cutting seton insertion with (Group A) or without (Group B) partial internal sphincterotomy. The subjects reported their postoperative pain at defecation and at rest respectively using a visual analogue scale (VAS). The intensity of pain between the two groups was compared. Results All the 40 patients were cured, without recurrence or fecal incontinence. During the period of cutting seton treatment, the pain scores at defecation and at rest were lower in the Group A than in the Group B ( P 0.05). Conclusions Internal sphincterotomy can significantly relieve anal pain after cutting seton treatment, being an effective method.

Objective [WT5”BZ]To evaluate the results of radical resection for the treatment of Budd Chiari syndrome (BCS) caused by short segmental lesions in inferior vena cava (IVC), and major hepatic veins (MHV).[WT5”HZ]Methods [WT5”BZ]In this series, resection of IVC occlusive segment and orthotopic artificial vascular graft transplantation were performed in 42 patients. Resection of major hepatic vein, hepatic venous plasty and orthotopic transplantation with artificial vascular graft were performed in 10 patients. Resection of major hepatic vein, anastomosis between hepatic vein and right artrium in 3 cases. Percutaneous transhepatic angioplasty in 10 cases.[WT5”HZ]Results [WT5”BZ]One patient died of complication. 58 cases were followed up for an average of 30 months. 3 cases in interventional group suffered recurrence and one in surgical group had recurrence.[WT5”HZ]Conclusions [WT5”BZ]The treatment of BCS by resecting inflicted segment of IVC or hepatic veins and orthotopic artificial vascular graft transplantation effect a radical cure in most cases.

Objective　To evaluate the results of radical resection for the treatment of Budd-Chiari syndrome (BCS) caused by short segmental lesions in inferior vena cava (IVC), and major hepatic veins (MHV).　Methods　In this series, resection of IVC occlusive segment and orthotopic artificial vascular graft transplantation were performed in 42 patients. Resection of major hepatic vein, hepatic venous plasty and orthotopic transplantation with artificial vascular graft were performed in 10 patients. Resection of major hepatic vein, anastomosis between hepatic vein and right artrium in 3 cases. Percutaneous transhepatic angioplasty in 10 cases.　Results　One patient died of complication. 58 cases were followed up for an average of 30 months. 3 cases in interventional group suffered recurrence and one in surgical group had recurrence.　Conclusions　The treatment of BCS by resecting inflicted segment of IVC or hepatic veins and orthotopic artificial vascular graft transplantation effect a radical cure in most cases.

Objective To understand the microcystin(MC-LR)pollution in drinking water in the city and countryside of Fuling District,Sichuan,China.Methods In 2004,285 water samples were collected from different types of water in Fuling district in different season and the concentration of LR(MC-LR),total phosphorus and total nitrogen in water were determined respectively.Results From July to November in 2004,no LR(MC-LR)was detected and the total phosphorus and total nitrogen did not exceed the national standard limits in the drinking water in the city,but in the secondary water supply in the city,the MC-LR was detected,the total phosphorus and total nitrogen exceed the standard limits.In the countryside,the MC-LR was detected,the total phosphorus and total nitrogen exceed the standard limits.Conclusion In the countryside of Fuling District,Sichuan,China,the drinking water,water source and tap water,was seriously contaminated by microcystin,the total phosphorus and total nitrogen exceed the national standard limits.

Objective To study the value of microwave coagulation therapy for liver malignant tumors.Methods Under local anesthesia,19 cases with hepatic malignant tumors treated with microwave knife under CT-guided.Results There were totally 23 tumors in 19 cases,13 tumors with≤3.5 cm in diameters were destroyed absolutely after the first treatmet,10 tumors among them were followed-up for 6-12 months and no recurred.10 tumors with＞3.5 cm in diameters treated at multiple points or angle,3～6 months later,CT showed that the tumors were destroyed completely in 6 and mostly in 4,by the hot condensate treatment secondly,3 tumors of 4 were destroyed completely 3 months later.There were no obvious complications.Conclusion The therapeutic effect under CT-guided microwave coagulation therapy for liver tumor which are ≤3.5 cm in diameter of the tumors is very reliable,the tumors＞3.5 cm in diameter can be destroyed mostly or completely by microwave treatment.

Objective To assess the value of blood perfusion of thyroid nodules using contrastenhanced ultrasonography(CEUS). Methods Blood perfusion parameters of 78 preoperative patients with thyroid nodule were examined using CEUS. Microvessel density(MVD) in the thyroid nodule specimens was calculated by immunohistochemical staining using anti-factor CD34. Results Compared to papillary thyroid carcinoma (PTC) and nodular goiter (NG), there was significant differences in peak value(PEAK),maximum value of video signal intensity(Slmax), and mean value of video signal intensity(SImean) in thyroid nodule with diameter ＜ 1 cm ( P ＜ 0. 05 ), the MVD of thyroid nodules was not statistically significant ( P ＞ 0.05). There were significant differences in regional blood volume and MVD in thyroid nodule with diameter ≥ 1 cm between two groups ( P ＜ 0.05). Conclusions The characteristics of blood perfusion are dissimilar for thyroid nodules with different sizes and properties. The quantitative analysis with CEUS can provide valuable information for clinical diagnosis.