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1.
Nature ; 467(7311): 64-7, 2010 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-20811453

RESUMO

The detection of circumstellar water vapour around the ageing carbon star IRC +10216 challenged the current understanding of chemistry in old stars, because water was predicted to be almost absent in carbon-rich stars. Several explanations for the water were postulated, including the vaporization of icy bodies (comets or dwarf planets) in orbit around the star, grain surface reactions, and photochemistry in the outer circumstellar envelope. With a single water line detected so far from this one carbon-rich evolved star, it is difficult to discriminate between the different mechanisms proposed. Here we report the detection of dozens of water vapour lines in the far-infrared and sub-millimetre spectrum of IRC +10216 using the Herschel satellite. This includes some high-excitation lines with energies corresponding to approximately 1,000 K, which can be explained only if water is present in the warm inner sooty region of the envelope. A plausible explanation for the warm water appears to be the penetration of ultraviolet photons deep into a clumpy circumstellar envelope. This mechanism also triggers the formation of other molecules, such as ammonia, whose observed abundances are much higher than hitherto predicted.

2.
Tumori ; 75(1): 53-6, 1989 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-2711475

RESUMO

This paper presents our experience of the problem of diagnosis and surgical treatment of malignant parotid tumors, based on a retrospective evaluation of a series of 478 parotid tumors, of which 100 were malignant. Out of 75 primaris malignant tumors of epithelial origin, 35 belonged to the "epidermoid" group (adenocarcinomas, undifferentiated carcinomas, malignant mixed tumors, squamous cell carcinoma), 20 were mucoepidermoid carcinomas, 15 adenoid cystic carcinomas and 5 were acinic cell carcinoma. Altogether, 58.7% of the treated patients do not at the moment present evidence of disease; 33.3% are dead from the disease or are alive with active disease; 5.3% are dead from other causes and 2.7% are lost to follow-up. Underlining the importance of histologic examination of the swelling by intraoperative biopsy, the authors propose a diagnostic and therapeutic protocol.


Assuntos
Neoplasias Parotídeas/terapia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Feminino , Humanos , Excisão de Linfonodo , Masculino , Pessoa de Meia-Idade , Neoplasias Parotídeas/diagnóstico , Neoplasias Parotídeas/patologia
3.
J Laryngol Otol ; 103(2): 181-6, 1989 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2926266

RESUMO

The results of 25 years of quasi-routine total parotidectomy performance are shown. At the Department of Otolaryngology of the University of Florence, 582 patients were treated as follows: on 527 occasions by total parotidectomy with facial nerve preservation; 24 occasions by lateral lobectomy; 27 occasions by total parotidectomy with removal of the whole facial nerve; four times by enucleo-resection of the disease. Benign tumours were 378; primary and metastatic malignant tumours--100; non tumoral lesions--104. The benign tumours follow-up showed three recurrences only (two pleomorphic adenomas--one of them proved to be an adenoid-cystic carcinoma, and one monomorphic adenoma, which also proved to be an adenoid-cystic carcinoma), respectively 6, 6 and 8 years later. The malignant tumours were also treated by total parotidectomy with adequate management both of the facial nerve and the neck lymph nodes. The results thoroughly justify the nerve preservation, when preserved.


Assuntos
Doenças Parotídeas/cirurgia , Glândula Parótida/cirurgia , Nervo Facial/cirurgia , Seguimentos , Humanos , Métodos , Recidiva Local de Neoplasia , Doenças Parotídeas/patologia , Glândula Parótida/patologia , Neoplasias Parotídeas/patologia , Neoplasias Parotídeas/cirurgia
6.
Pathologica ; 81(1076): 611-6, 1989.
Artigo em Italiano | MEDLINE | ID: mdl-2561405

RESUMO

Two rare cases of laryngeal paraganglioma are reported. The first patient was a 14-year-old girl, that had a new laterocervical paraganglioma, 4 years after the excision of a laryngeal tumor. The other patient was a 33-year-old man. In both the cases, the diagnosis was made on histopathological ground and the tumors displayed the typical histological pattern of paragangliomas: epithelioid tumor cell arranged in nests (Zell-ballen) in a vascular stroma. Neoplastic cells were found to contain argyrophil granules and chromogranin. Laryngeal paragangliomas reported in the literature are 73, they generally are supraglottic, show no sex predilection and prefer the V-VII decades of age.


Assuntos
Neoplasias Laríngeas/patologia , Paraganglioma Extrassuprarrenal/patologia , Adolescente , Adulto , Feminino , Humanos , Neoplasias Laríngeas/diagnóstico por imagem , Masculino , Paraganglioma Extrassuprarrenal/diagnóstico por imagem , Radiografia
7.
Eur Arch Otorhinolaryngol ; 254(6): 301-3, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9248740

RESUMO

The authors describe a rare case of three neurinomas arising in the parapharyngeal space. In spite of the large extension of the neoplasms, the only symptom reported by the patient was some dysphagia. Magnetic resonance imaging allowed us to identify the three masses and suppose their diagnosis. The therapeutic approach used is also reported.


Assuntos
Neoplasias Primárias Múltiplas/patologia , Neurilemoma/patologia , Neoplasias Faríngeas/patologia , Adulto , Humanos , Neoplasias Hipofaríngeas/patologia , Neoplasias Laríngeas/patologia , Masculino
8.
Radiol Med ; 81(4): 520-5, 1991 Apr.
Artigo em Italiano | MEDLINE | ID: mdl-2028045

RESUMO

The results were analyzed of 175 patients with glottic squamous cell carcinomas who were treated with curative purposes (1970-1986). One hundred and sixteen of them underwent surgery at the Otolaryngology Department of the University of Florence, and 59 were treated by radiation therapy at the Florence University and Hospital Departments of Radiotherapy. In the surgical series 78 cases were treated with radical surgery and 38 with conservative surgery. All patients were staged according to TNM system (UICC 1978) as T2. Overall 10-year local control rates were 74% for the surgical series and 69% for the cases treated by radiation therapy. After salvage therapy 10-year survival rates were 83% and 76%, respectively. The analysis of the results showed no statistically significant difference. In the group treated by radical surgery 80% local control was observed, versus 66% in the cases treated with conservative surgery. 10-year survival rate was higher in the latter group (89% versus 81%) because of better results of salvage therapy: 7 of 10 recurrences were salvaged with the second treatment. Several prognostic factors were evaluated, i.e., T extent, anterior commissure involvement, subglottic invasion, vocal cord mobility impairment, and ventricular involvement. Anterior commissure involvement was the main factor affecting outcome in the surgical series: in the presence of this factor, 64% 10-year local control was observed versus 85% in the patients without commissure involvement. This factor proved more important in the patients treated with conservative surgery (10-year control: 42% versus 88%) than in those undergoing radical surgery (78% versus 85%). Anterior commissure involvement and the number of involved subsites were found to worsen prognosis in the series treated by radiation therapy: cases with anterior commissure involvement had 59% 10-year local control versus 83%. The cases with a deeper spread had 60% local control versus 75%. Vocal cord mobility impairment was a less important prognostic factor in both series. Our results suggest radiation therapy as a valuable method in the treatment of the small T2 laryngeal cancers which are not suitable for conservative surgery.


Assuntos
Carcinoma de Células Escamosas/radioterapia , Carcinoma de Células Escamosas/cirurgia , Glote , Neoplasias Laríngeas/radioterapia , Neoplasias Laríngeas/cirurgia , Carcinoma de Células Escamosas/mortalidade , Feminino , Humanos , Neoplasias Laríngeas/mortalidade , Laringectomia , Masculino , Pessoa de Meia-Idade , Prognóstico , Dosagem Radioterapêutica , Fatores de Tempo
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