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41.
Contradictory results have been reported about the inhibitory input to the medial rectus subdivision of the oculomotor nucleus of the cat. In the present ultrastructural study, we quantified the GABAergic and glycinergic terminals in the various subdivisions of the rabbit oculomotor nucleus with the use of post-embedding immunocytochemistry combined with retrograde tracing of horseradish peroxidase. The density of the GABAergic input to the medial rectus subdivision was as substantial as that to the other subdivisions and the postsynaptic distribution of the GABAergic and glycinergic innervation did not differ among the different oculomotor subdivisions.  相似文献   
42.
报告105例Duchenne型肌营养不良症(DMD),其中男103例,女2例。年龄4~19岁,平均65岁。32例有阳性家族史。文中对DMD的临床表现,血清酶、肌肉病理、组织化学、电镜检查等特点进行了讨论。对其中4例骨骼肌进行肌纤维膜冷冻断裂电镜检查。结果表明,本病肌膜的E面和P面的膜蛋白颗粒密度降低,与2例正常骨骼肌相比有显著性差异,支持本病发病机理中的“膜缺陷”学说。  相似文献   
43.
A retrospective analysis of treatment for endometrial carcinoma is reported here. From 1987 to 1989, 138 patients were referred to the oncology department following total abdominal hysterectomy and bilateral salpingo-oophorectomy for endometrial cancer. Forty-seven patients were not prescribed postoperative radiotherapy; 31 had Stage I well differentiated adenocarcinoma with minimal myometrial invasion, while the remaining 16 patients were considered unfit for postoperative radiotherapy. There were no instances of local relapse amongst the 31 patients with minimal myometrial invasion.The remaining 91 patients all received external beam irradiation to the pelvis and, according to the preference of the individual therapist, 51 were prescribed additional intracavitary vault caesium-137. Patients receiving postoperative radiotherapy were analysed according to whether or not they received additional intracavitary vault caesium. The two groups were also analysed for incidence of vaginal vault recurrence and treatment related morbidity.In the group receiving additional intracavitary treatment more patients had Stage II or III disease (P<0.05), and had greater depth of myometrial invasion (P<0.05). Vaginal vault recurrence was not observed in patients receiving intracavitary therapy in addition to external beam therapy. Four patients (10%) receiving external beam therapy alone developed vaginal vault recurrence.The incidence of Kottmeier-Perez grade 2 or 3 bowel toxicity following treatment was significantly higher in those patients receiving combined treatment (18% vs. 2.5%; P<0.03). There was also a higher incidence of vaginal stenosis in the group receiving both external beam and intracavitary therapy (21% vs. 3%; P<0.05). There was only one instance of grade 2 bladder toxicity in the external beam and intracavitary treatment group and none in the external beam therapy alone group.In conclusion, postoperative radiotherapy for Stages I-III endometrial carcinoma was carried out in a non-randomized manner by two regimens; either external beam therapy alone or external beam therapy with additional intracavitary vaginal caesium. The combined therapy gave significantly better local control but resulted in significantly more late bowel and vaginal morbidity.  相似文献   
44.
马超  孙新臣 《现代医学》2004,32(6):397-399
目的 探讨局部性尤文肉瘤的综合治疗效果。方法 收集经综合治疗的 2 5例尤文肉瘤患者的临床资料 ,采用Kaplan Meier法进行分析、Logrank法检验 ,分析治疗方式和化疗周期对疗效的影响。结果 综合治疗局部性尤文肉瘤的有效率为 92 % (2 3 /2 5 )。治疗结束后病灶完全消退组患者的 1、3、5年生存率 (10 0 %、93 .8%和 81.3 % )明显高于病灶未完全消退组 (10 0 %、75 .0 %和 5 0 .0 % ) (均P <0 .0 5 )。行 6个周期化疗的患者 1、3、5年生存率 (10 0 %、93 .8%和 66.7% )高于 3个周期者 (88.9%、77.8%和 5 5 .6% ) (均P <0 .0 1)。局部采用手术或放疗对疗效无明显影响 (P >0 .0 5 )。结论 经综合治疗 ,局部性尤文肉瘤病灶完全消退者生存期明显延长 ,化疗周期的次数是影响疗效的重要因素。  相似文献   
45.
李文瑜 《循证医学》2004,4(4):210-213
目的 应用Meta分析的方法评价进展期霍奇金病经化疗达完全缓解后巩固放疗的作用。材料和方法 在MEDLINE、CBMdisc数据库检索进展期霍奇金病化疗达完全缓解行巩固性放疗或不行巩固性放疗的前瞻性随机对照研究。对入选研究的总生存、无事件生存优势比进行Meta分析。结果 4项研究入选,以α=0.05为检验水准,巩固性放疗组与对照组(不作巩固性放疗)相比,5年总生存优势比=1.18,P=0.46;5年无事件生存优势比=1.05.P=0.83:巩固性侵犯野放疗组与对照组相比,5年总生存优势比=0.96,P=0.87。结论 进展期霍奇金病经化疗达到完全缓解后,巩固性放疗对总生存及无事件生存均无益处。  相似文献   
46.
BACKGROUND: Electron beam tomography coronary calcium imaging is an evolving technique for the early detection of coronary atherosclerosis, and recent studies have established its prognostic value in asymptomatic individuals. The relationship of coronary artery calcium scores (CAC) to obstructive coronary artery disease (CAD) has been poorly studied but is clinically relevant because it determines which individuals are likely to benefit from revascularization procedures. Hence, we prospectively evaluated the prevalence of myocardial ischemia in asymptomatic patients with cardiovascular risk factors and subclinical atherosclerosis. METHODS AND RESULTS: We studied 864 asymptomatic patients with no previous CAD but with cardiovascular risk factors, referred for electron beam tomography coronary calcium imaging to our institution over an 18-month period. From this group, 220 consecutive patients (85% men; mean age, 61 +/- 9 years; age range, 31-84 years) with moderate to severe atherosclerotic disease (coronary calcium score > or =100 Agatston units) were prospectively evaluated by technetium 99m sestamibi single photon emission computed tomography (SPECT). Patients were followed up (mean follow-up, 14 months) and data regarding their subsequent clinical management recorded. Of the 220 patients, 119 had moderate atherosclerosis (CAC score of 100-400 Agatston units) and 101 had severe atherosclerosis (CAC score > or =400 Agatston units). Abnormal SPECT findings were seen in 18% of patients with moderate atherosclerosis (n = 21) and 45% of patients with severe atherosclerosis (n = 45). Increasing severity of atherosclerosis was related to increasing ischemic burden (summed difference score = 1 +/- 0.2 for CAC score of 100-400 Agatston units and 3.2 +/- 0.5 for CAC score > or =400 Agatston units). In a multivariate linear regression model incorporating risk factors, CAC was the only predictor of silent ischemia. CONCLUSION: In comparison to previously published data, we detected a higher prevalence of silent ischemia even in patients with moderate coronary atherosclerosis (18%). This may reflect the differing risk factor profile of our patient population. When coronary calcium screening is used to preselect asymptomatic patients with cardiovascular risk factors for myocardial perfusion imaging, the optimum coronary calcium score threshold will depend on the population prevalence of risk factors and asymptomatic obstructive CAD.  相似文献   
47.
目的 探讨以顺铂为主的化疗方案加放疗对局部晚期非小细胞肺癌的疗效。方法 86例局部晚期非小细胞肺癌患随机分为治疗组及对照组各43例,放疗方案以CAP、EP、MVP或MOP,每人至少化疗两个周期,化疗后10~14天放射治疗,放疗采用^60Co外照射。结果 治疗组有效率83.7%,中位生存期14.5个月,对照组有效率67.4%,中位生存期10个月,两组不良反应为骨髓抑制、胃肠道反应。结论 以顺铂为主的化疗方案加放疗治疗局部晚期非小细胞肺癌的疗效较高,可提高肿瘤的局部控制率和延长生存期。  相似文献   
48.
Masumi Ichikawa   《Brain research》1987,420(2):253-258
The rearrangement of terminations from the bed nucleus of stria terminalis (BST) was examined in the medial amygdaloid nucleus (MAN) at 2 months following the lesion of the accessory olfactory bulb (AOB) using an electron microscopy and degeneration study. At 2 days following a BST lesion, the number of degenerating synapses was 0.7 ± 0.1 (mean±S.E.M.) per unit area (2500 μm2 in the molecular layer, and 3/0 ± 0.3 in the cellular part. At 2 months after an AOB lesion, the degenerating synapses from the AOB had completely disappeared from the MAN. The BST was then lesioned at 2 months after the AOB lesion and, 2 days following this BST lesion, the degenerating synapses were counted in MAN. The numbers observed were 3.3 ± 0.6 per unit area in the molecular layer and 4.5 ± 0.4 in the cellular part. Therefore, the number of these degenerating synapses increased significantly within the molecular layer, though, in the cellular part the number of synapses was not significantly elevated over control. No differences in postsynaptic profiles (ratio of synapses on dendritic spine to dendritic shaft) were observed after the AOB lesion. These results indicate that the BST fibers formed new synapses in the molecular layer following the denervation of AOB fibers. The possibility of new synapse formation by other afferent fibers in addition to the AOB fibers is discussed as is the relationship between lesion induced synaptic reorganization and functional recovery after injury.  相似文献   
49.
Summary The histogenesis of stromal cells in capillary hemangioblastoma has been the subject of debate. The light and electron microscopic studies of hemangioblastomas presented here showed pericytic and leiomyoblastic features in stromal cells. Cells cultured by the monolayer method showed similar features to those of the original tumors. Immunohistochemical studies for glial fibrillary acidic protein and factor VIII/von Willebrand factor indicated that stromal cells were antigenically distinct from astrocytes and endothelial cells. These findings suggest that stromal cells are closely related to pericytes and smooth muscle cells, and support Rhodin's speculation that pericytes serve as a precursor to smooth muscle cells.  相似文献   
50.
食管癌三维适形后程加速超分割放射治疗的疗效分析   总被引:3,自引:0,他引:3  
目的评价三维适形后程加速超分割放射治疗食管癌的疗效及放疗反应、并发症。方法2002年2月至2004年5月,71例食管鳞癌随机分成两组,三维适形后程加速超分割组36例,食管病变上下外约4cm,前后、左右外约0.5~1cm作为PTV1,每次2GY,每周5次,DT40GY后,病变上下外约2cm,前后、左右外约0.5~1cm作为PTV2,每日2次,每次1.5GY,间隔4~6小时,总疗程6周,总剂量67GY/38次。非三维适形后程加速超分割组35例,时间、剂量、分割方式同适形组。所有病例均采用8MV-X外照射。结果1、2、3年的生存率和原发肿瘤的局控率,与非适形后程加速超分割比较,适形组明显提高,分别为88.9%、75%、63.9%比68.6%、51.4%、40%和86.1%、72.2%、58.3%比65.7%、48.5%、34.3%。适形组的急性放射反应明显低于非适形后程加速超分割组,两组有显著差别。结论本研究的初步结果表明食管癌适形后程加速超分割放射治疗的疗效优于非适形后程加速超分割组。  相似文献   
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