Upon the previous studies on the effect of spinal cord repair kinetics, we report the effect of extending the irradiation schedules to 3 treatment day per week. The animals in the experimental group received a pair of 2Gy fraction every other day separated by intervals (day/overnight) of 6h/42h and 8h/40h, respectively. There was significant shift by increasing interfraction intervals from 6/18h and 8/16h to6h/42h and 8h/40h, respectively. It is suggested that the tolerance of spinal cord is reduced while the overnight intervals are shortened from 42h and 40h to 18h and 16h, respectively and the repair of sublethal damage of spinal cord following multifraction treatment per day used in the clinic is not completed. With biexponential model, the ?/? ratio derived from these pooled data was 2.2Gy. T 1/2 values from spinal cord were obtained as 1.3h and 5.5h. It showed that the repair kinetics parameters are in well agreement with the results from the previous work. The repair processes are not influenced by interruption during radiotherapy.

The biology rationale for radiotherapy in the treatment of malignant disease is based on repair, repopulation,reoxygenation and cell cycle redistribution. Various aspects of the roles of the 4R' are discussed, including in determining the sensitivity of tumors and normal tissue tolerances. An improvement in therapeutic ratio may derive from reducing the dose per fraction and minimizing the overall treatmemt duration. Some methods have developed to predict the response of normal and tumor tissues before radiotherapy. The parameters of cell survival at 2Gy(SF2) was correlated with clinical outcome. There is reasons to suppose that the pretreatment tumor LI and Tpot mat be good predictors for tumor repopulation kinetics. This review also discussed the rationale for the use of LQ model in fractionated radiotherapy.

Objective To correctly apply the Capability Maturity Model Integration(CMMI) model to the development process of medical device software,thus optimizing and improving the development process and enhancing the software process capability.Methods The matching between CMMI and IEC62304 was analyzed.The compatibility on application was investigated by taking risk management(the core process) as an example.Results The interface between CMMI and IEC62304 was discovered as well as their optimized process in risk management.Conclusion The process of medical device software development not only can be improved by CMMI model,but also should be.

Objective To analyze the clinical characteristics, treatment and prognosis of primary parotid non-Hodgkin's lymphoma. Methods From March 1988 to February 2001, twenty-nine patients with primary parotid non-Hodgkin' s lymphoma treated in our hospital were retrospectively analyzed. The data were analyzed according to the following factors: sex, age, stage, pathologic classification, chemotherapy given or not, cycles of chemotherapy, radiotherapy given or not, and the dose at the parotid. Kaplan-Meier method and Log-rank method were used in the statistic analysis. Results The overall 5-year and 10-year survival rates were 73. 3% and 51.0% . Stage and pathologic classification were prognostic factors in our statistic analysis. The 5-year survival rates were 81.6% and 25.0% for early stage ( I E + IIE) and advanced stage ( III E + IVE) patients, with the difference significant ( P

Background and purpose:Radical cystectomy is viewed as the standard treatment for bladder carcinoma,but organ preservation has been attempted for patients with muscle-invasive bladder carcinoma over the past decades as an alternative to radical cystectomy.The majority of studies included transurethral resection of bladder tumor(TURB),radiotherapy,and chemotherapy,as a feasible and safe organ-sparing approach with the similar outcome to radical cystectomy.The current study evaluated the outcomes and complications of the radiation therapy for the patients with bladder cancer,and prognosis factors had been analyzed.Methods:We retrospectively analyzed 21 patients with bladder cancer.The clinical stages of the patients were 15 with T_2;5 with T_3 and 2 with T_4.2 of them were lymph node-positive,16 of patients were pathologically proved as transitional cell carcinoma,4 as adenocarcinoma and 1 as transitional cell carcinoma plus squamous cell carcinoma.Conventional fractionation radiotherapy was given at a median dose of 54.5Gy(ranged 49.2-69.9 Gy) after surgery.Kaplan-Meier method and Logrank method were used for the statistical analysis.Results:Median follow-up was 32 months.The overall survivals at 1 year,3 years and 5 years were 90.5%,47.1%,and 36.7% respectively.The local disease free rates were 95.0%,62.4%,and 47.5% respectively.15 of 16 patients' deaths were related to the tumor.In univariate analysis,only small field irradiation was found as a prognosis factor in survival(?~(2)=5.36,P=0.02).Conclusions:Combined treatment appears to provide high response rates and can be offered as an alternative option to radical cystectomy for selected patients who refuse or are unsuitable for surgery.A large number of patients,multicenter,prospective randomized trial would be desirable to evaluate the role of radiotherapy in the multi-modality treatment of bladder cancer.

Objective To explore whether pravastatin protects endothelium against the damage induced by homocysteine (Hcy) in isolated rabbit aorta. Methods Endothelium-dependent relaxation responses to acetylcholine (ACh) of thoracic aortic rings were measured by isometric tension recording before and after aortic rings exposed to Hcy in the absence or presence of pravastatin (PT) to estimate the injury effect of Hcy and the protective effect of pravatatin on rabbit aortic endothelium, respectively. Results Incubation of aortic rings with 1～10mmol/L Hcy for 30min significantly inhibited endothelium-dependent relaxation response to ACh of aortic rings in a concentration-dependent manner. Pre-incubation of aortic rings with 0.3～3mmol/L PT for 15min and co-incubation of aortic rings with 3mmol/L Hcy for another 30min markedly attenuated the inhibition of endothelium-dependent relaxation induced by Hcy in a concentration-dependent manner. Conclusion Pravastatin can improve the impairment of endothelium-dependent relaxation induced by Hcy in isolated rabbit aorta.

Objective To analyze the clinical feature, diagnosis, treatment a nd prognostic factors of primary lymphoma of the small bowel. Methods From Apr il 1989 to May 2002, 33 patients with non-Hodgkin's lymphoma of the small bowel were analyzed retrospectively. The Ann Arbor stages were: ⅠE 12, ⅡE 15 and Ⅳ E 6. The histological subtypes were: T-cell lymphoma 1 and B-cell lymphomas 32. A ll the patients received surgical treatment including radical or palliative rese ction. Twenty-six patients received postoperative radiotherapy including strip -f ield technique in 12 and opposed anterior-posterior fields in 14, with a median dose of 2543.5?cGy. Postoperative chemotherapy were applied to all patients inclu ding CHOP regimen in 17, COMP regimen in 6, COP regimen in 3, MINE regimen in 2, COPP regimen in 3 and BACOP regimen in 2. The median number of cycle was 4. Results The overall 5-year survival rate and disease-free survival rate were 48% and 39%. The 5-year survival rates were: ⅠE stage 42%, ⅡE stage 67% and ⅣE s tage 17%, respectively. Conclusions Most of the primary non-Hodgkin's lymphoma of the small intestine are in stage ⅠE and ⅡE, and the intermediate-grade and h igh-grade pathological subtypes are predominant. Surgery based combined treatme n t is effective and is advised. Radiotherapy and chemotherapy may improve the sur vival.

Objective To analyze the pregnancy outcome of laparoscopy cervical cerclage before pregnancy in treatment of uterine cervical insufficiency. Methods The clinical data of 78 uterine cervical incompetence patients having underwent cervical cerclage before pregnancy were retrospectively analyzed. Among them 40 cases underwent laparoscopy cervical cerclage (laparoscopy group), and 38 cases underwent transvaginal cervical cerclage (transvaginal group). The operation time, complications, length of cervix in pregnancy, lengthen time of gestational weeks, gestational weeks, perinatal infant weight, survival rate of perinatal infants and infection rate of uterine cavity were compared between 2 groups. Results The length of cervix in pregnancy, lengthened time of gestational weeks, perinatal infant weight, term labor rate and survival rate of perinatal infants in laparoscopy group were significantly higher than those in transvaginal group: (4.35 ± 0.52) cm vs. (3.51 ± 0.66) cm, (116.7 ± 9.8) d vs. (90.2 ± 5.2) d, (3 050 ± 759) g vs. (2 500 ± 431) g, 60.0%(24/40) vs. 31.6%(12/38) and 95.0%(38/40) vs. 78.9%(30/38), and the infection rate of uterine cavity was significantly lower than that in transvaginal group: 2.5% (1/40) vs. 18.4% (7/38), and there were statistical differences (P<0.05). There were no statistical differences in operation time and incidence of complications (P > 0.05). Conclusions Laparoscopy cervical cerclage before pregnancy in treatment of uterine cervical incompetence can effectively maintain the cervical length period of pregnancy, improve the success rate of surgery, prolong gestational weeks, and improve perinatal outcome.

Objective To study the pre- pregnancy cervical cerclage method in the different cervical length of uterine cervical incompetence patients. Methods The clinical data of 128 uterine cervical incompetence patients having underwent pre-pregnancy cervical cerclage were retrospectively analyzed. The preoperative cervical length was measured by transvaginal ultrasound. Cervical length >2.5 cm was in 60 cases, of which 34 cases underwent laparoscopic cervical cerclage, and 26 cases underwent transvaginal cervical cerclage; cervical length ≤ 2.5 cm was in 68 cases, of which 32 cases underwent laparoscopic cervical cerclage, and 36 cases underwent transvaginal cervical cerclage. Results For the patients with preoperative cervical length > 2.5 cm, there were no statistical differences in the postoperative pregnancy cervical length, gestational weeks time, perinatal birth weight, perinatal survival rate, gestational age of delivery and intrauterine infection rate between 2 methods (P>0.05). For the patients with preoperative cervical length ≤ 2.5 cm, the postoperative pregnancy cervical length, gestational weeks time, perinatal birth weight, perinatal survival rate and gestational age of delivery in laparoscopic cervical cerclage patients were significantly higher than those in transvaginal cervical cerclage patients: (3.85 ± 0.37) cm vs. (3.16 ± 0.49) cm, (101.75 ± 4.71) d vs. (80.62 ± 3.53) d, (2850 ± 323) g vs. (2330 ± 585) g, 90.6% (29/32) vs. 69.4% (25/36) and 50.0% (16/32) vs. 22.2%(8/36), but the intrauterine infection rate was significantly lower than that in transvaginal cervical cerclage patients:0 vs. 16.7%( 6/36), and there were statistical differences (P<0.05). All patients had no obvious complications. Conclusions For cervical length > 2.5 cm patients with uterine cervical incompetence, pre- pregnancy cervical cerclage can choose transvaginal or laparoscopic. But for patients with the cervical length≤2.5 cm or previous cervical cerclage failure, laparoscopic cervical cerclage is better than transvaginal cervical cerclage.

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