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41.
The purpose of this study was to evaluate the dose to normal tissues as a function of increasing margins around the lumpectomy cavity in accelerated partial breast irradiation (APBI) using 3D-conformal radiotherapy (3DCRT). Eight patients with Stage 0-I breast cancer underwent treatment planning for 3DCRT APBI. The clinical target volume (CTV) was defined as a 15-mm expansion around the cavity limited by the chest wall and skin. Three planning target volumes (PTV1, PTV2, PTV3) were generated for each patient using a 0, 5-, and 10-mm expansion around the CTV, for a total margin of 15, 20, and 25 mm. Three treatment plans were generated for every patient using the 3 PTVs, and dose-volume analysis was performed for each plan. For each 5-mm increase in margin, the mean PTV:total breast volume ratio increased 10% and the relative increase in the mean ipsilateral breast dose was 15%. The mean volume of ipsilateral breast tissue receiving 75%, 50%, and 25% of the prescribed dose increased 6% to 7% for every 5 mm increase in PTV margin. Compared to lesions located in the upper outer quadrant, plans for medially located tumors revealed higher mean ipsilateral breast doses and 20% to 22% more ipsilateral breast tissue encompassed by the 25% IDL. The use of 3DCRT for APBI delivers higher doses to normal breast tissue as the PTV increases around the lumpectomy cavity. Efforts should be made to minimize the overall PTV when this technique is used. Ongoing studies will be necessary to determine the clinical relevance of these findings.  相似文献   
42.
目的探讨单臂外固定支架联合腓肠肌内侧头肌皮瓣治疗胫腓骨骨折合并胫前大面积皮肤撕脱伤的疗效。方法18例患者先进行急诊清创,采用单臂AO外固定支架固定骨折、腓肠肌内侧头肌皮瓣局部旋转覆盖外露胫骨。撕脱的皮肤修成全厚皮片回植供皮区,其中5例仍有缺损,另取同侧大腿全厚皮片移植。结果均无感染,15例旋转皮瓣完全成活,2例皮瓣远端表皮坏死,经换药治愈,1例皮瓣远端全层坏死,经植皮治愈。撕脱皮片回植13例成活,5例小部分坏死,其中3例经换药治愈,2例经中厚皮片植皮愈合。5例大腿皮片完全成活。平均随访19.5(10~36)个月,骨折平均愈合时间4(3.5~6)个月。所有患者行走正常,3例膝关节屈伸活动受限,4例踝关节屈伸受限。结论采用单臂外固定支架联合腓肠肌内侧头肌皮瓣治疗胫腓骨骨折合并胫前大面积皮肤撕脱伤,疗效肯定。  相似文献   
43.
Ilizarov技术矫正儿童僵硬型马蹄内翻足畸形   总被引:1,自引:0,他引:1  
[目的]探讨Ilizarov技术矫正僵硬性马蹄内翻足畸形的方法和效果。[方法]作者在2000年3月~2005年3月间,使用Ilizarov技术矫正9例11足重度僵硬性马蹄内翻足畸形,将连接于胫骨、跟骨、跖骨的外固定环互相连接、组合成复杂的三维外固定架,通过逐渐调整外固定架矫正畸形,从而使患足达到或接近正常足的外形和功能。[结果]按Garceau标准评定疗效,优6足,良4足,差1足。[结论]Ilizarov外固定架三维矫正马蹄内翻足畸形效果确实,尤其适用于大年龄儿童之僵硬、复发或难治性马蹄内翻足,有一定的临床应用价值。  相似文献   
44.
EMG responses in the external anal sphincter (EAS), the rectus abdominis muscle (RA), and the anterior tibial muscle (TA) were recorded following single magnetic transcranial cortical stimulations (TCCS) in seven healthy volunteers. The responses in the EAS differed from the responses in the other muscles. They had comparatively long durations ranging from 1 to 2 seconds, no inhibitory periods were observed, and there was no tendency for habituation to occur following a limited number of stimuli. The responses recorded in the EAS were used as test responses in order to evaluate the excitability changes in the EAS motoneurons occurring during bladder filling. Cystometries with filling rates of 15, 50 and 200 ml/min were done. During these cystometries TCCS were applied repeatedly, with constant strength, after each 50 ml of filling up to bladder capacity. The responses following TCCS changed in a highly reproducible way during bladder filling. After 100–200 ml of filling, the responses had longer latencies, diminished sizes, and shorter durations. When the filling reached a level 50–150 ml below capacity, the responses in most subjects again became greater and the latencies shorter. The changes were believed to be physiological. It was concluded that the EAS motoneurons are under both inhibitory and facilitatory influence during bladder filling in intact healthy humans. Facilitatory influences are often observed when the bladder is filled close to capacity. At lower bladder volumes the observed influence is always inhibitory. A decrease in the EMG activity of the EAS during filling cystometry should consequently not be regarded as a pathological response.  相似文献   
45.
We report on the vaginal mucosal folds (VMF) at the urethral external meatus. Resection of the VMF reduces the dispersed micturition and other urinary symptoms. EDITORIAL COMMENT: The investigators describe the presence of a vaginal mucosal fold (VMF) just dorsal to the urethral meatus and its relationship to voiding abnormalities. VMF were found on physical examination in 8.9% of the clinic population, all of whom complained of dispersed micturition, and 79% also experienced other voiding abnormalities. The complaint of dispersed micturition was successfully treated with excision of the VMF, and the other associated symptoms were improved. This structure should be routinely looked for on physical examination, especially in patients with voiding symptoms. Only further investigation of this newly described entity at other centers around the world will determine the incidence of the anatomic finding and the prevalence of associated voiding disturbances across different populations.  相似文献   
46.
慢性体外反搏对高胆固醇血症猪动脉内皮细胞的影响   总被引:7,自引:0,他引:7  
目的 探讨慢性增强型体外反博(EECP)能否在体修复高胆同醇血症引起的猪动脉内皮细胞(ECs)损伤。方法 高胆固醇血症猪反搏36h后,取前降支进行扫捕电镜检查,收集胸主动脉ECs进行蛋白质组学检查。结果 高脂组冠脉ECs排列不规则、大量脱落、斑块形成,反搏组ECs呈流线型排列、脱落程度显著减轻:与高脂组相比,在反搏组的ECs检测到6种高表达的蛋白。结论 慢性EECP可能通过调节ECs蛋白表达,改善ECs粘附性和代谢及减轻ECs内皮凋亡,从而修复高胆固醇血症对动脉内皮形态和功能的损伤:  相似文献   
47.
Rats with catatonic freezing are characterized by low motor and explorative activity in the open field test and specific pattern of external respiration, so-called strenuous respiration, which is accompanied by a higher activity of the respiratory enzymes succinate dehydrogenase and NADH dehydrogenase in the hippocampus and motor cortex. No dependencies on the brain structure and animal age are noted. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 124, No. 8, pp. 138–140, August, 1997  相似文献   
48.
49.
目的:为设计阴部外动脉阴茎皮瓣转位尿道成形术提供依据。方法:30侧经动脉内灌注红色乳胶的成人尸体,解剖观测阴部外动脉起始、行程;着重阴部外动脉阴茎支在阴茎的走行、分支分布。结果:阴部外动脉始于股动脉,外径1.8±0.4mm,伴行静脉1-2支,汇入大隐静脉。阴茎支可视为本干的延续,经耻骨结节两侧靠近阴茎,分别经2(10)点、3(9)点和1(11)点进入阴茎,多数分出背侧支、腹侧支分布阴茎皮肤。外径0.8±0.2mm。结论:阴茎皮肤血管恒定,以阴茎支为蒂,可在阴茎外侧或背外侧、腹外侧设计皮瓣,用于尿道成形术。术式已在临床应用,效果满意。  相似文献   
50.
We have established stable, bright green fluorescent protein (GFP)- or red fluorescent protein (RFP)-expressing HT-1080 human fibrosarcoma clones. These cell lines showed similar cell proliferation rates and high-frequency experimental lung metastasis. The HT-1080-GFP and -RFP clones enable simultaneous real-time dual-color imaging in the live animal. HT-1080 cells were transduced with retroviral vectors containing GFP or RFP and the neomycin resistance gene. Stable transformants were selected stepwise with G418 up to 800 μl/ml. Subsequently, high GFP- or RFP-expressing clones, HT-1080-GFP or HT-1080-RFP, respectively, were selected. 3×106 cells from each clone were mixed and injected into the tail vein of SCID mice. The cells seeded the lung at high frequency with subsequent formation of pure green and pure red colonies as well as mixed yellow colonies with different patterns visualized directly on excised lungs. The lung metastases were also visualized by external fluorescence imaging in live animals through skin-flap windows over the chest wall. Lung metastases were observed on the lung surface of all mice. SCID mice well tolerated multiple surgical procedures for direct-view imaging via skin-flap windows. Real-time metastatic growth of the two different colored clones in the same lung was externally imaged with resolution and quantification of green, red, or yellow colonies in live animals. The color coding enabled determination of whether the colonies grew clonally or were seeded as a mixture with one cell type eventually dominating, or whether the colonies grew as a mixture. The simultaneous real-time dual-color imaging of metastatic colonies described in this report gives rise to the possibility of color-coded imaging of clones of cancer cells carrying various forms of gene of interest. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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