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D Chevalier

Publications and source records attributed to D Chevalier.

At least 73 records · Page 4Linked to original sources
PubMed1991

[Subtotal laryngectomy in the treatment of extensive tumors of the larynx].

The authors assess the possibility to perform subtotal laryngectomy for extensive tumors of the endolarynx. They describe a particular variety of T3/T4 tumor extending anteriorly to the thyroid cartilage or to the pre-epiglottic space. Such tumors do not affect the arytenoid cartilages posteriorly, which makes functional subtotal laryngectomy with CHP or CHEP possible. This surgery was performed in 28 patients from 1972 to 1985, with 20 patients still living after 5 years, ie. 72% of all cases.

Humans↗
PubMed1991

[Liposarcoma of the infratemporal fossa. Apropos of a case].

The authors report about one female patient with a liposarcoma of the right infratemporal fossa. Such tumors are rare, making up 10 to 12% of all soft-tissue sarcomas. Their occurrence in a cervical site is rare, unlike that in the inguinal region, the retroperitoneum or the lower limbs. Their diagnosis is mainly established by the histopathological study. Computed tomography and magnetic resonance imaging are particularly useful to choose the surgical approach. The technique chosen for this infratemporal tumor was a transmandibular cervical approach. Evolution was favorable, and the patient has currently had no reoccurrence after two years.

Adult↗
PubMed1990

[Medium-malignancy tumors of the parotid gland].

Among the 437 parotidectomies performed from 1966 to 1989, we observed 2 acinar-cell tumors and 11 mucoepidermoid carcinomas, ie. 3%. The acinar-cell tumors occurred in 2 men aged 45 and 71. A conservative complete parotidectomy was performed in both cases with a 6 and 7-year survival without local recurrence. The mucoepidermoid tumors affected 4 women and 7 men. The clinical appearance in 2 cases was highly suggestive of a malignant tumor, the picture including facial palsy, fixed gaze and adenopathy. In spite of excision completed by radiation therapy, the outcome soon was unfavorable. In the other 9 patients presenting with a limited tumor of the parotid gland, the facial nerve had to be partly sacrificed in 2 cases because no dissection was possible even under a microscope. The prognosis was generally favorable in the limited forms with 6/6 patients alive at more than 5 years and 3 patients alive at 3 years, 2 years and 1 year. Postoperative radiation therapy was not performed systematically, but only in 2/3 of cases (ill-delineated or ill-differentiated tumor).

Adolescent↗
PubMed1990

[Laryngectomy with Tucker's epiglottoplasty].

From 1980 to 1987, 37 patients were operated with a reconstructive anterior frontal laryngectomy including epiglottoplasty such as described by Tucker. These patients presented with epidermoid carcinomas of the glottis. The carcinological results are satisfactory, with a survival rate of 33 of 37 patients at 3 years and 22 of 25 patients at 5 years. However, the control of the paraglottic space still is insufficient after this type of surgery, and we reserve it for the tumors confined to the glottic level, without impairment of mobility. The anterior frontal laryngectomy performed is extensive and frontolateral. It is used for a few of its former indications, as showed by the comparison of the periods before and after 1980.

Carcinoma, Squamous Cell↗
PubMed1989

Surgical treatment of angiofibromas of the nasopharynx--34 cases.

Between 1966 and 1987 we have treated 34 angiofibromas. The patients were between 9 to 28 years of age (average 16.5 years). The tumour extension was determined formerly by tomography and angiography, but these two methods have been replaced by angioscanning, which give the best results. Nineteen patients were classified stage I, fourteen stage II and one stage III. The surgical approach was transmaxillary in most cases. After tumour resection, two local recurrences were seen and a second operation was necessary to achieve a definitive cure in these patients.

Adolescent↗
PubMed1989

[Endonasal ethmoidectomy in the treatment of polyposis].

The authors report their experience with 210 microsurgical ethmoidectomies carried out in 109 patients between 1980 and 1987. In 23 patients the anatomy was considerably modified due to previous surgery. Asthma was present in 56 patients and 25 patients suffered from Widal's syndrome. The complications noted included 1 case of meningitis cured by antibiotics and a case of transient diplopia. Patients were monitored for 1 to 6 years; In 69 cases no recurrence was noted (63% of cases), 31 patients (28%) only required minor local procedures for slight recurrence (28%). On the other hand, 6 patients (5.5%) required a second surgical procedure for recurrence between 3 and 6 years.

Asthma↗
PubMed1988

A plasmid of Rhizobium meliloti 41 encodes catabolism of two compounds from root exudate of Calystegium sepium.

Our objectives were to identify substances produced by plant roots that might act as nutritional mediators of specific plant-bacterium relationships and to delineate the bacterial genes responsible for catabolizing these substances. We discovered new compounds, which we call calystegins, that have the characteristics of nutritional mediators. They were detected in only 3 of 105 species of higher plants examined: Calystegia sepium, Convolvulus arvensis (both of the Convolvulaceae family), and Atropa belladonna. Calystegins are abundant in organs in contact with the rhizosphere and are not found, or are observed only in small quantities, in aerial plant parts. Just as the synthesis of calystegins is infrequent in the plant kingdom, their catabolism is rare among rhizosphere bacteria that associate with plants and influence their growth. Of 42 such bacteria tested, only one (Rhizobium meliloti 41) was able to catabolize calystegins and use them as a sole source of carbon and nitrogen. The calystegin catabolism gene(s) (cac) in this strain is located on a self-transmissible plasmid (pRme41a), which is not essential to nitrogen-fixing symbiosis with legumes. We suggest that under natural conditions calystegins provide an exclusive carbon and nitrogen source to rhizosphere bacteria which are able to catabolize these compounds. Calystegins (and the corresponding microbial catabolic genes) might be used to analyze and possibly modify rhizosphere ecology.

Alkaloids↗
PubMed1988

[Cystadenolymphoma of the parotid gland. A study of 40 cases].

A statistical review of 40 cases of adenolymphoma (Whartin's tumor) of the parotid gland is presented. In 10% of the cases, other tumors are found in the same concerned gland. Therefore, the authors perform a subtotal parotidectomy rather than a simple removal of the tumor of a superficial parotidectomy. This policy reduces the risk of facial nerve injury by repeated dissection.

Adenolymphoma↗
PubMed1987

[Severe laryngeal stenoses in adults. Results of the Réthi-Ward enlarging technic].

Treatment of severe cricoid stenosis with fixed vocal cords is difficult, the often used Réthi operation producing 20 to 30% of unsuccessful results. Use of a hyoid bone pedicle flap allows anterior enlargement with cricoid ring reconstruction, in addition to the classical posterior enlargement, and was successful in 8 of 9 cases treated by this method.

Adult↗
PubMed1984

Interaction of plasma fibronectin (pFN) with membranous constituents of peritoneal exudate cells and pulmonary macrophages.

The prominent role of plasma fibronectin (pFN) in the host defense system as an opsonin for gelatin (collagen)-coated colloids has been established. In the present study we investigated the interaction of pFN and membrane isolates from cells devoid of collagen, as well as several tissues. In a liver slice assay system it was shown that subcellular membrane fractions from lung macrophages, peritoneal exudate cells, spleen, tests, and liver were able to competitively inhibit the pFN-mediated uptake of 125I-gelatin coated latex beads (gLtx) at low concentrations. Endocytosis of 125I-labeled membrane isolates by macrophage monolayers was also promoted by addition of pFN. In an attempt to characterize the membrane component(s) interacting with pFN, it was found that mild extraction procedure with 1 M KBr could release a significant amount of this inhibitory activity. Further studies demonstrated that the agent(s) responsible for inhibition of gLtx uptake was heat sensitive, not altered by trypsin treatment, and did not contain actin, a protein known to interact with pFN. This work indicates that pFN interacts specifically with an as yet unknown membrane component(s) and that such interaction will promote clearance of cellular debris by macrophages. This suggests that pFN may be an important opsonin for the reticuloendothelial system in clearance of collagenous and noncollagenous cellular debris once they are exposed to interact with it.

Animals↗
PubMed1984

A new method for the simultaneous analysis of free and sulfoconjugated normetanephrine, metanephrine, and 3-methoxytyramine in human urine by HPLC with electrochemical detection.

A sensitive and specific assay for free and sulfoconjugated normetanephrine, metanephrine, and 3-methoxytyramine was achieved by tetraphenylboron complexing and by high-performance liquid chromatography with electrochemical detection. Sulfoconjugated metabolites were hydrolyzed by sulfatase. Complexing the 3-O-methylated catecholamines with tetraphenylboron followed by their extraction in either and reextraction in dilute hydrochloric acid succeeded in partially purifying the sample without the use of a prepacked column. Detection by electrochemical technique additionally eliminates unoxidable components in the urine. The relatively high sensitivity of this method permits measurement of metabolite concentrations as low as 10 ng/ml, allowing for the first time the determination of free 3-O-methylated catecholamines in human urine. Hydrolysis by sulfatase specifically identifies the form of the conjugated metabolite. The mean total (free plus sulfoconjugated) values of normetanephrine, metanephrine, and 3-methoxytyramine obtained from 25 normal volunteers were 214, 102, and 227 micrograms/day, respectively. Values were greatly increased in patients with pheochromocytoma. The degree of sulfoconjugation varied, and each individual metabolite was highest with normetanephrine (86%). This method is sensitive, rapid, simple, and can be easily standardized for clinical investigation of pheochromocytoma.

Adrenal Gland Neoplasms↗