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81.
From June 1977 through March 1981, the Radiation Therapy Oncology Group sponsored a Phase I-II study (RTOG 77-05) on the use of fast neutrons for treating carcinomas of the urinary bladder. Patients entered on the study had Stage B1 (grade III or IV histology) or Stage B2, C, or D1 (any grade histology) disease. Thirteen patients received preoperative mixed-beam (neutron/photon) irradiation to 50 photon Gy-equivalent, and in 12 of these a cystectomy was performed in 4 to 6 weeks. The incidence of pathologic downstaging to Po was 58% in the cystectomy specimens. The projected survival at 30 months is 32%. Twenty-six patients were treated definitively with mixed-beam irradiation consisting of 50 photon Gy-equivalent to the pelvis followed by a 20 photon Gy-equivalent boost to the bladder itself. Eighteen of 26 patients (69%) achieved tumor clearance at some time during their follow-up but 8/18 (44%) of these ultimately exhibited some component of local failure. The projected survival at 30 months for this group of patients is 34%. However, the subset of patients with Stage B or C disease had a projected survival at 30 months of 60%. Four patients received definitive neutron irradiation alone and 3/4 achieved tumor clearance at some time during their follow-up. Actuarial curves are presented for patient survival and duration of local control, and results are compared with comparably staged patients treated with megavoltage photon irradiation. Treatment-related morbidity is also discussed.  相似文献   
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Fast neutrons were used in the management of 30 patients with advanced salivary gland tumors. Twenty-two patients are the subject of this analysis. Neutrons were used as the primary mode of management in only seven patients. The remaining patients either had recurrent disease after surgery and/or radiation, or received post-operative treatment with neutrons. After a minimum follow-up of one year, 66% of the patients are alive with no evidence of disease. Control in the treatment volume is as high as 72%, which suggests a significant improvement in the local control of advanced salivary gland tumors. However, longer periods of observation are necessary for more definitive conclusions.  相似文献   
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Postirradiation atrophic changes of bone and related complications   总被引:2,自引:0,他引:2  
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86.
Anatomical organization of primate visual cortex area VII   总被引:4,自引:0,他引:4  
The Golgi Rapid and Kopsch techniques have been used to provide material for an examination of the internal neuronal organization of cortical area VII of the Macaca monkey. The afferent and efferent relationships of area VII, as shown by axoplasmic transport tracing techniques in our own material and in previous studies in other laboratories, are reviewed. Comparison is made between the internal organisation of VI and VII cortex in terms of (1) the marked different in spiny and nonspiny neurons populations of granular layer 4, (2) the difference in relationship of lamina 6 pyramidal neurons to the overlying layers with a shift away from any relationship to granular layer 4 in VII, and (3) differences in the organization of VI lamina 4B and VII lamina 3B--both similarly placed, fiber-rich bands in the two cortical areas. The extrinsic relationships of VI and VII with the lateral geniculate nucleus, superior colliculus, pulvinar, peristriate cortex, cortical area STS, and with each other are compared in terms of laminar locations of efferent neurons and afferent axon terminal fields. It is hoped that this anatomical survey will provide a better foundation for physiological explorations of the region.  相似文献   
87.
A follow-up study of lens opacities, utilizing retro-illumination photography with the fundus camera is described. After giving technical details, results are discussed and possible errors pointed out. If evaluation by planimetry or other devices is not possible, a useful procedure is the evaluation of simultaneous projected slides by a group of ophthalmologists not directly involved in the trial. This is demonstrated by testing the effect of 1-hydroxy-pyrido-(3,2alpha)-5-phenoxazone-3-carboxylic acid on the progress of senile cataract in a total of 48 eyes. Together with slit image photography of Brown (2, 3) the method of retro-illumination photography of the lens presented in this paper is a definite improvement in demonstrating the temporal course of cataract development.  相似文献   
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