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Six types of photoreceptors in the red area (dorso-temporal quadrant) of the pigeon retina are identified using Golgi impregnation, light microscopy and electron microscopy. Golgi impregnation is used to categorize the receptors into morphological types. Examination of oil droplets in the inner segments of cones in fresh, unfixed tissue shows five different types which can be characterized by color, size and stratification. Therefore, in sections through the length of the receptors examined by electron microscopy, the oil droplets contained in the inner segments of the cones can be identified as to their color by their characteristics (i.e., size and stratification), and the groups of receptors thus classified, further characterized as to the morphology of their terminals. Rods have no oil droplets in their inner segments, and their synaptic terminals are located in the outermost stratum of the outer plexiform layer (OPL). Principal members of double cones have yellow oil droplets in their inner segments, while accessory members contain small colorless oil droplets. The synaptic terminals of double cones are located in the same (outermost) stratum of the OPL as rod synaptic terminals. Two types of single, straight cones house either red or orange oil droplets and terminate in the intermediate stratum of the OPL. Oblique single cones with yellow-green oil droplets in their inner segments contribute synaptic terminals to the innermost stratum of the OPL.  相似文献   
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Small bowel metastases from renal cell carcinoma (RCC) are very rare. Clinical presentation includes obstruction, bleeding, intussusception and rarely perforation. We report a case of a 48-year-old female presenting a jejunal intussusception due to intestinal metastasis from RCC. To our knowledge, there are only a few such cases reported in the literature (seven cases). However, if considered in the total summary of reported cases with small bowel metastases from RCC, intussusception is a probable cause.  相似文献   
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OBJECTIVE: The goal of this work was to assess retrospectively the role of wide/radical hysterectomy (RH) and pelvic lymph node dissection (LND) in endometrial cancer with cervical involvement. METHODS; From 1984 to 1993, 82 patients with endometrial cancer and cervical involvement were surgically managed at our institution. Of 57 patients with stage II (59%) or III (41%) disease receiving no preoperative therapy, 22 (39%) had simple hysterectomy (SH) and 35 (61%) had RH. Forty-four patients (77%) had pelvic LND, and 38 (67%) had adjuvant radiotherapy (RT). Median follow-up was 70 months. RESULTS: The 5-year disease-related survival (DRS) and recurrence-free survival (RFS) were 73 and 63%, respectively. Five-year DRS and RFS were 68 and 50%, respectively, in the SH group compared with 76% (P = 0.1) and 71% (P = 0.04) in the RH group. Distant recurrences occurred in 45% of patients with SH and in 23% with RH (P = 0.08). Local recurrence rates did not differ significantly. Considering only stage II tumors, we did not observe any recurrence among patients with negative nodes who had RH, irrespective of the administration of adjuvant RT. By contrast, adjuvant RT improved local control (even if not significantly) in stage II patients who had SH. Five-year DRS of stage III patients was 47%, but it was improved by adjuvant RT in the subgroup of patients who had RH. Independent variables associated with prognosis were stage III disease, deep myometrial invasion, RH, and adjuvant RT. CONCLUSION: RH and adjuvant RT appear to improve prognosis in endometrial cancer with cervical involvement. In particular, radical surgery alone is therapeutic in stage II patients with negative nodes, irrespective of the administration of RT. By contrast, RT can possibly improve local control in stage II patients who previously had SH. Overall, stage III patients have a poor prognosis that can be improved by a combination of radical surgery and adjuvant RT; however, associated therapy directed to extrapelvic sites is probably needed in patients with extrauterine disease.  相似文献   
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