The multi drug resistance(MDR) of tumor cells has become a difficult problem in the chemotherapy of tumor, meanwhile, the mechanism of MDR are various:relevant drugs with reversal effects have been discovered. This review will provide the most impossible mechanisms of MDR and some prospecting reversal drugs.

Objective To explore the experience in scalp operation of craniopagus and repairing of scalp and dura defect after separating Methods Analysis the cause and management of the complication after skin expander implantation Discuss the characteristic of repairing skull soft tissue defect by expanded scalp flap and fiber capsule Results Dural and scalp defect could be repaired satisfactory with expanded scalp at one stage Conclusion It's necessary and important for successful separation in D type craniopagus with preoperation care, an elabarate operative management, careful postoperative observation and timely treatment for complication

Objective To investigate the effect of nerve growth factor(NGF)in the process of muscular neurotization of denerva- ted vascularized skeletal muscle.Method By using NGF(0.5 ?g/d) to transplanted skeletal muscle,muscular neurotization was exa- mined with histological,histochemical,electron microscope and immunohistochemical methods at various time.Result NGF was effective in promoting muscular neurotization and diminishing denervated muscle atrophy in grafted denervated skeletal muscle.Conclusion NGF can promote the muscular neurotization and diminish denervated muscle atrophy.

Objective To compare the values of the mangled extremity syndrome index (MESI), the mangled extremity severity score (MESS) and the limb salvage index (LSI) in deciding amputation or salvage in the management of the mangled extremity syndrome (MES). Methods Clinical data of 353 MES patients including 95 with amputation and 258 with salvage admitted in recent eight years were retrospectively evaluated by using MESI, MESS and LSI, the value of which in deciding amputation or salvage was assessed with receiver operating characteristic ( ROC ). Results There was statistical difference in aspect of mean scores of three grading systems between patients with amputation or salvage (P＜0. 01). For MESI, MESS and LSI, the sensitivities was 89.47%, 85.26% and 83.15% respectively, the specificities was 100%, 96.89% and 96.12% respectively, the coincidence was 97.16%,93.76% and 92.63% respectively, the areas under ROC curves was 0. 924, 0905 and 0. 861 respectively and the cut-off points were equal or over 20, 7 and 6 respectively. Conclusions Three scoring systems are all highly capable of predicting early amputation or not in MES management. The MESI is recommended as a quantitative criterion for determining amputation or salvage.

Objective To discuss the value of preoperative digital design of struetund bone graft for acetabular wall defects. Methods The . dieom data from spiral CT scans were imported into Mimics 10.0 to build the 3D solid model of the pelvis of an old female patient with left acetabular wall defects. The 3D solid model of the defect area was built by Mirror and 3D mask editing. A simulated bone graft was conducted on the 3D model by segmentation and trimming according to the data measured on the reconstructed model. Results The reconstructed 3D model of the patient's pelvis could be presented in different colors, transparenees, or combinations of interested tissues. The acetabular wall defects could be visualized very clearly at different angles. The geometric data of the bone graft could be measured to ensure the bone graft would fit the defects accurately. Conclusion Preoperative digital design based on 3D com-puterized reconstruction of acetabular wall defects may provide a valuable aid to clinical treatment, because it is a simple, rapid, and accurate method of increasing the fitness of bone graft and the defects,

Objective To evaluate the modified Physical and Operative Severity Score for the Enumera-tion of Mortality and Morbidity (POSSUM) in predicting the postoperative morbidity in patients with fractures of the pelvis and acetabulum. Methods The clinical data of 94 patients with pelvic and acetabular fractures were retrospectively analyzed. Their postoperative prognosis during hospital stay was evaluated with the POSSUM scoring system modified according to the features of orthopedics and pelvic and acetabular fractures. The peritoneum in-fection in the severity index of operation was replaced by operative approach, the several operations at one time by operative duration, and the cancer by the associated injury. The size and type of operation were made into 4 grades with corresponding orthopedic scores. The scores were compared between the complication group and the non-complication group. The receiver operator characteristic (ROC) curve was drawn to describe the coincidence degree, define the cut points, and evaluate its predicting capability. Results The mean preoperative physi-ological score (PS) and operative severity score (OS) in the complication group (38 cases) were significantly higher than those in the noncomptication (56 cases) (17.26 ± 2.84 vs 16.04 ± 2.77; 19.50 ± 5. 14 vs 13.00 ±3.81 ) ( P ＜ 0.05) . In the modified POSSUM, the area under ROC curve was 0. 856, the cut point 43%, sen-sitivity 73.68%, specificity 80. 36%, and coincidence degree 77.66%. Conclusions Since the modified POSSUM scoring system has a high capability of predicting postoperative morbidity for fractures of the pelvis and acetabulum, it can be helpful for surgeons to lower operative risks and ensure safety in operation. When the score is higher than the cut point, the risk is too great for an operation. Therefore, the fracture should be treated non-operatively or mini-invasively until the score is lower than the cut point.

Objective: To study the epidemiological of social anxiety disorder in pupils of Zhanjiang urban districts. Methods:2409 pupils from 5 elementary schools in Zhanjiang city completed the SASC. Those with a total score higher than 2 standard deviation away from the mean were interviewed. SADC was diagnosed according to the standard of CCMD-3.Results:The overall prevalence rate of SADC was 2.74 in Zhanjiang urban districts, prevalence rate for boys was 2.6, while 2.9 for girls. No sex difference was found (?~2=0.11,P=0.744). There was no significant difference among different grades (?~2=5.47,P=0.361).Conclusions:SADC exists in pupils of Zhanjiang city, we should pay more attention to this disorder for children's mental health.

Objective To evaluate the efficacy and safety of low energy intracardiac cardioversion in persistent atrial fibrillation. Methods Low energy intracardiac cardioversion was performed by delivering R wave synchronized biphasic shocks in 7 patients(4 men, 3 women) with persistent atrial fibrillation. Prior to the procedure, all patients underwent transesophageal echocardiographic examinations to rule out the presence of intracardiac thrombus and received subcutaneous injection of low molecular weight heparin for 3 5 days. Two custom made 6 Fr catheters(Rhythm Technologies of Getz, USA) were used for de fibrillation shock delivery. One catheter was positioned in the lower right atrium so that the majority of the catheter electrodes had firm contact with the right atrial free wall. The second catheter was placed randomly either in coronary sinus through right internal jugular vein or in the left pulmonary artery through femoral vein. In addition, a standard diagnostic 6 F quadropolar catheter was placed at the right ventricular apex for ventricular synchronization and postshock ventricular pacing. Shocks were delivered by Implant Support Device(Model 4510, Teleceronics). After conversion, all patients were treated with intravenous amiodarone in the first 24 hours followed by oral administration. Results In all 7 patients cardioversion of atrial fibrillation to sinus rhythm was successfully obtained. A mean of 2?1 shocks per patient has been delivered with a total amount of 13 shocks. The average delivered energy was 7.8?2.2 Joules. No complication occurred. At a mean follow up of 18?9 months, 4 of the 7 patients treated successfully showed sinus rhythm there after. Atrial fibrillation recurred in 3 patients at the second, fifth day and eighth month after cardioversion. Conclusions Low energy intracardiac cardioversion is effective and safe, and can be easily performed in patients without geneal anesthesia. It offers a new option for restoring sinus rhythm in patients with persistent atrial fibrillation.

Objective To study clinical and histopathological features of high-risk small renal carcinoma and provide theoretical basis for the individualized treatment.Methods This retrospective study analyzed the clinical and histological data of 21 patients of high-risk small renal cell carcinomas which were highly aggressive or advanced stage, admitted from Jan 2000 to July 2015.There were 15 males and 6 females,and the average age was (61.5 ±7.1) years (ranged 27 to 75 years).The mean diameter of tumors was 3.3cm (ranged 2.0 to 4cm).The study mainly focused on pathological character and stage, Fuhrman grading, existence of perirenal tissue or vascular invasion, venous embolus and distant metastasis.Results Of all these 21 cases, 17 cases were clear cell carcinomas, 1 was papillary carcinoma, 2 were hybrid cellular tumor ( malignant rhabdoid tumor and sarcomatoid carcinoma) and 1 was sarcomatoid carcinoma. Among the 17 clear cell carcinoma cases, 12 were Fuhrman grade Ⅱ, 5 were grade Ⅲ and one was gradeⅣ.Tumor infiltrated renal vein or its branches and renal vein embolus were found in 7 cases.The tumor infiltrated perirenal or renal sinus fat were found in 11 cases.Synchronous lung and local lymph nodes metastasis were found in 3 patients respectively.Moreover, there was 1 case with metastasis to the brain (FuhrmanⅣ).The final clinical stage were T3a N0M0 in 14,T1a N1M0 in 3 and T1a N0M1 in 4 cases. Conclusions Small renal tumors are heterogeneous in its biological behavior and the minorities are aggressive with infringement of perirenal fat or simultaneous local lymph node or distant metastasis.When the tumor is greater than 3.0 cm in diameter and with high grade in Fuhrman classification, sarcomatoid carcinoma are more likely to be highly aggressive and advanced stage.

Opioid peptides and their receptors play an important r ole in the pathophysiologic process of stroke. The concentration of endogenous o pioid peptides elevates, while the density of opioid receptors decreases in CNS during cerebral ischemia; on the other hand, opioids influence the development o f stroke through regulating the contraction of cerebral vessel, immuno-endocrin e system and neuroprotection against injury. Thus, drugs that regulate the opioi d system may be a new therapeutic approach for prevention and treatment of cereb ral ischemia.