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101.
102.
Gambacorta MA Manfrida S D'Agostino G Digesù C D'Onofrio I Rosato H Valentini V 《Rays》2005,30(2):181-187
Based on the successful results achieved in survival and local control with radiotherapy of prostate cancer recent studies tried to establish some models to reliably predict late rectal toxicity. In fact, the rectum, due to its location, represents an organ at risk of acute and late toxicity with the onset of acute or chronic radiation proctitis. The concept of late consequential effect has gained ground. It implies that the late damage might be a direct consequence of the acute damage. Dose-escalation studies, conformal radiotherapy (3D-CRT) and intensity modulated radiotherapy (IMRT) led to the identification of parameters, based on dose-volume histograms (DVH), able to separate patients at low and high risk of toxicity. Precise predictive dosimetric factors play a major role in the definition of the onset of toxicity. The monitoring system of late toxicity used by the authors is presented. 相似文献
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104.
Anatomical radical retropubic prostatectomy: 'curtain dissection' of the neurovascular bundle 总被引:5,自引:0,他引:5
OBJECTIVE: To investigate the topographical relationship of the cavernosal nerves (CNs) to seminal vesicles, prostate, rhabdosphincter and urethra during the development of the prostate, and to use the resulting morphological data to modify the surgical technique of nerve-sparing radical prostatectomy. MATERIALS AND METHODS: The study included 29 male fetuses (gestational age 9-37 weeks) and eight adult specimens assessed anatomically and histologically. Using the plastination technique and anatomical dissection, the course of the CNs was investigated in all specimens. Based on these morphological results, the technique of dissecting the CNs during nerve-sparing radical retropubic prostatectomy was modified. RESULTS: During early fetal development the fibres of the CNs enclose the prostatic and membranous urethra dorsally and laterally. During the growth of the prostate, the CNs running along the prostate become displaced further anteriorly and spread, thus forming a concave shape (like a 'curtain') of the neurovascular bundles (NVB). Therefore, dissection of the NVB has to start anteriorly to preserve all the nerve fibres that are spread along the surface of the lateral lobes of the prostate. CONCLUSIONS: From these anatomical findings we propose a modified 'curtain dissection' to improve preservation of the CNs running in the NVB, in which the incision of the periprostatic fascia and dissection of the NVB is far more anterior than previously described. 相似文献
105.
Zanow J Kruger U Petzold M Petzold K Miller H Scholz H 《Journal of vascular surgery》2005,41(6):913-1012
OBJECTIVES: In this report we present a novel procedure that uses an arterioarterial prosthetic loop (AAPL) with the proximal axillary or the femoral artery as a vascular access for hemodialysis in patients who have inadequate vascular conditions for creating an arteriovenous fistula or graft. METHODS: Between April 1996 and September 2004, 34 patients received 36 AAPLs as vascular access, either as an axillary chest loop (n = 31) or as a femoral loop (n = 5). In this procedure the artery is ligated between the anastomoses to direct flow through the AAPL. Data from all patients undergoing the procedure were prospectively collected. RESULTS: The indication for an AAPL was the unsuitability of large deep veins in 64%, steal syndrome in 11%, the combination of only a suitable femoral vein and severe peripheral arterial disease in 22%, and congestive heart failure in 3%. All AAPLs were cannulated 18 +/- 4 days postoperatively. Mean follow-up was 31 months (range, 1 to 83). Primary patency was 73% and secondary patency was 96% at 1 year; these rates at 3 years were 54% and 87%, respectively. The rate of all interventions for the maintenance of AAPL function was 0.47 procedures per patient year. Four grafts were abandoned. More than 11,000 hemodialyses with proven efficiency were performed. CONCLUSIONS: The AAPL is an unusual but useful and easy-to-perform alternative procedure to create vascular access for hemodialysis. It can provide survival for strictly selected patients in whom conventional vascular access is not possible. The axillary chest AAPL is preferred. 相似文献
106.
Brevik A Vollset SE Tell GS Refsum H Ueland PM Loeken EB Drevon CA Andersen LF 《The American journal of clinical nutrition》2005,81(2):434-439
BACKGROUND: Nutritional biomarkers may be used to assess dietary exposure without the errors commonly associated with self-reported dietary data. OBJECTIVE: The objective was to examine the association between plasma folate and intake of folate, fruit, and vegetables in a large cohort of healthy adults consuming foods that had not been fortified with folic acid. DESIGN: The present study population included 5533 middle-aged (47-49 y) and old (71-74 y) subjects from the Hordaland Homocysteine Study. The participants completed a food-frequency questionnaire and provided blood samples for chemical analyses. RESULTS: We observed a significant difference in plasma concentrations of folate across increasing quartiles of fruit, vegetable, and orange juice consumption. The difference in plasma folate between the highest and lowest quartiles was 1.97 (95% CI: 1.86, 2.07) nmol/L for fruit intake, 1.79 (95% CI: 1.69, 1.89) nmol/L for vegetable intake, and 2.69 (95% CI: 2.51, 2.87) nmol/L for orange juice intake. A significant inverse relation was observed across increasing quartiles of milk and bread intakes. The difference between the highest and lowest quartiles was -1.03 (95% CI: -1.13, -0.92) nmol/L for milk and -1.60 (95% CI: -1.69, -1.50) nmol/L for bread. CONCLUSION: Plasma folate concentration may be a useful biomarker for the intake of fruit and vegetables in populations consuming unfortified food products. The association can be attenuated by and should be corrected for individual intake of folic acid supplements. 相似文献
107.
108.
Pyrethroids used indoor-ambient monitoring of pyrethroids following a pest control operation 总被引:1,自引:0,他引:1
Leng G Berger-Preiss E Levsen K Ranft U Sugiri D Hadnagy W Idel H 《International journal of hygiene and environmental health》2005,208(3):193-199
House dust and airborne particles (PM) were sampled before (T1) and 1 day (T2), 4-6 months (T3) as well as 10-12 months (T4) after a pest control operation (PCO). Cyfluthrin was applied in 11, cypermethrin in 1, deltamethrin in three and permethrin in four interiors. The pyrethroid concentrations in house dust and PM were measured by GC/MS with a detection limit for all pyrethroids of 0.5 mg/kg house dust and of 1 ng/m3 PM for deltamethrin and permethrin and 3 ng/m3 PM for cyfluthrin and cypermethrin. A general background concentration of permethrin (95th percentile: 5.9 mg/kg) and cyfluthrin (95th percentile: 34.9 mg/kg) in house dust was found. In general, an appropriately performed PCO lead to an increase of pyrethroids in house dust as well as in PM, in some cases up to 1 year after application. One day after the application the cyfluthrin concentration increased significantly from 0.25 (T1) to 33.8 mg/kg house dust (T2) and up to 4.9 ng/m3 in PM. The permethrin concentration increased significantly from 4.3 to 70 mg/kg in house dust and up to 18.1 ng/m3 in PM, deltamethrin increased to 54.5 mg/kg and 20.8 ng/m3 and cypermethrin to 14 mg/kg and 45.7 ng/m3. Thereafter a continuous decrease could be observed during the time course of 1 year. After 1 year the permethrin concentration in house dust was still 1/5 of the T2 concentration, whereas for cypermethrin and cyfluthrin only 1/14 and 1/23 of the T2 concentration were found. Deltamethrin was not detected at all after T2. Moreover, the data of this study showed significant, positive correlations between pyrethroids in house dust and in airborne particles especially one day after PCO. 相似文献
109.
110.
Synthesis and Pharmacological Test of 2- and 3-Substituted Pyrano[2,3-b]indolones . The condensation of oxindole (3a) with ethyl 2-methylacetoacetate (6b) leads to the propionyloxindole 4 . With the acetal esters 6f, 6g and 6h and the cyclic β-ketoesters 12, 13 and 14 the reaction results in the 3-acyloxindoles 7f, 7c , and 7d or 7h and 15a, 15b, 15c . These can be cyclised to the 2- and 3-substituted pyrano[2,3-b]indolones 16a–16c and 17a–17c . 相似文献