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To analyze the influence of the topical use of basic fibroblast growth factor (bFGF) in the regeneration of the facial nerve in rats.

BACKGROUND: Carcinomas of the external auditory canal are rare neoplasms (<1% of all head and neck malignant neoplasms). OBJECTIVE: To evaluate the prognostic factors in 79 patients treated in a single institution. PATIENTS AND METHODS: The disease was staged as follows: 34 patients with stage T1 to T2 tumors; 43 patients with stage T3 to T4 tumors; 2 patients with stage TX tumors; 68 patients with stage NO tumors; and 11 patients with stage N1 tumors. The initial treatment was surgery in 59 patients and radiotherapy in 9 patients. Eleven patients were not considered candidates for treatment. RESULTS: To date, 29 patients have experienced local recurrences and 2, neck metastases. The 5-year survival rates were 65% for patients who underwent surgery, 29% for patients who underwent radiotherapy, and 63% for patients who underwent a combination of surgery and radiotherapy. Univariate survival analysis showed statistical difference according to tumor type (P=.003), bone involvement (P=.002), and tumor stage (P<.001). CONCLUSION: Every effort must be undertaken to make an early diagnosis and perform radical surgical resection of squamous cell carcinomas in the external auditory canal. This study validates the staging system used for squamous cell carcinoma of the ear treated with surgery.Arch Otolaryngol Head Neck Surg. 1997;123:720-724

The Amazon River mainstem of Brazil is so regulated by differences in the timing of tributary inputs and by seasonal storage of water on floodplains that maximum discharges exceed minimum discharges by a factor of only 3. Large tributaries that drain the southern Amazon River basin reach their peak discharges two months earlier than does the mainstem. The resulting backwater in the lowermost 800 km of two large southern tributaries, the Madeira and Purús rivers, causes falling river stages to be as much as 2–3 m higher than rising stages at any given discharge. Large tributaries that drain the northernmost Amazon River basin reach their annual minimum discharges three to four months later than does the mainstem. In the lowermost 300–400 km of the Negro River, the largest northern tributary and the fifth largest river in the world, the lowest stages of the year correspond to those of the Amazon River mainstem rather than to those in the upstream reaches of the Negro River.