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1.
Nat Mater ; 12(9): 808-14, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23749266

RESUMEN

The rich internal degrees of freedom of magnetic domain walls make them an attractive complement to electron charge for exploring new concepts of storage, transport and processing of information. Here we use the tunable internal structure of a domain wall in a perpendicularly magnetized GaMnAsP/GaAs ferromagnetic semiconductor and demonstrate devices in which piezoelectrically controlled magnetic anisotropy yields up to 500% mobility variations for an electrical-current-driven domain wall. We observe current-induced domain wall motion over a wide range of current-pulse amplitudes and report a direct observation and the piezoelectric control of the Walker breakdown separating two regimes with different mobilities. Our work demonstrates that in spin-orbit-coupled ferromagnets with weak extrinsic domain wall pinning, the piezoelectric control allows one to experimentally assess the upper and lower boundaries of the characteristic ratio of adiabatic and non-adiabatic spin-transfer torques in the current-driven domain wall motion.


Asunto(s)
Imanes , Semiconductores , Anisotropía , Arsenicales/química , Electricidad , Diseño de Equipo , Galio/química , Modelos Teóricos , Torque
2.
Rev Stomatol Chir Maxillofac ; 92(1): 39-43, 1991.
Artículo en Francés | MEDLINE | ID: mdl-2047732

RESUMEN

129 patients, who had oral cavity or oropharyngeal carcinoma underwent excision with intraoperative histopathologic examination. Thanks to this method, the number of satisfying resections has increased from 25% to 75%. Whatever the quality of the surgical excision may be, postoperative radiotherapy improves the prognosis.


Asunto(s)
Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/cirugía , Neoplasias de la Boca/patología , Neoplasias de la Boca/cirugía , Neoplasias Orofaríngeas/patología , Neoplasias Orofaríngeas/cirugía , Carcinoma in Situ/patología , Carcinoma in Situ/cirugía , Carcinoma de Células Escamosas/radioterapia , Terapia Combinada , Femenino , Humanos , Cuidados Intraoperatorios , Masculino , Persona de Mediana Edad , Neoplasias de la Boca/radioterapia , Invasividad Neoplásica , Estadificación de Neoplasias , Neoplasias Orofaríngeas/radioterapia , Tasa de Supervivencia
3.
Cancer ; 63(7): 1437-51, 1989 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-2646010

RESUMEN

Prognostic factors were evaluated in 109 soft tissue sarcomas of the extremities, walls of the trunk, head, and neck. All lesions were graded according to the systems proposed by the National Cancer Institute (NCI) and the French Federation of Cancer Centers (FNCLCC), and a correlation was found between tumor grade and prognosis. Univariate analysis selected the following variables as unfavorable prognostic factors: invasive tumor margins, extra-compartmental status, deep tumors, tumor diameters over 5 cm, inadequate excision, presence of necrosis, high mitotic count, histologically undifferentiated tumors, and blood vessel invasion. These variables were found to be interdependent. Multivariate analysis selected quality of surgery as the most important variable for predicting local recurrences. The factors selected with regard to overall and metastasis-free survival were tumor size, tumor margins, necrosis, and adequacy of excision. These results permitted classification of patients into four prognostic groups: two with good and two with bad prognosis. Five-year survival for the four groups was 100%, 83%, 53%, and 0%; 5-year metastatic rates were 0%, 12%, 67%, and 100%. Similar groups were obtained when the variables of tumor margins and size were combined with an adaptation of the NCI grading (low-grade tumors/high-grade tumors without necrosis/high-grade tumors with necrosis). Comparative analysis showed that patients with tumors of the same histologic grade or type were not necessarily classed in the same prognostic groups. A better clinicopathologic correlation was obtained using a combination of prognostic factors than with histologic grading or typing alone.


Asunto(s)
Extremidades , Neoplasias de Cabeza y Cuello/patología , Sarcoma/patología , Estadística como Asunto , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Francia , Neoplasias de Cabeza y Cuello/mortalidad , Humanos , Masculino , Persona de Mediana Edad , Invasividad Neoplásica , Recurrencia Local de Neoplasia , Pronóstico , Factores de Riesgo , Sarcoma/mortalidad
4.
J Radiol ; 70(1): 7-16, 1989 Jan.
Artículo en Francés | MEDLINE | ID: mdl-2715971

RESUMEN

The authors report their experience with follow-up cytohistological examination of subclinical thoracic lesions in oncology by transparietal puncture with CAT-scanning localization in 170 patients. They detail a few special points concerning the material used and their techniques, in view of reducing the most common incidents and of managing the most severe complications. They analyze their results in two groups of patients, one investigated in a context of known malignancy and the other, with no history of malignancy in whom bronchoscopy, bronchial lavage and brushing were negative. They found an overall sensitivity and specificity of 86% and 100%, respectively, in the diagnosis of malignant disease. The method showed an efficacy of 83.5%. For the two populations, sensitivity was 84% and 87% respectively, and efficacy was 82 and 85% respectively. Thus, the results were better in the patients who had never received anticancer therapy. They also observed significant differences depending on whether the targets were mediastinal, pleuropulmonary or parietal. While the rapid diagnostic information appears invaluable in both groups of patients, in contrast, the small volume of the specimens, which may be hemorrhagic, necrotic, with more or less extensive fibrosis of the stroma, and the immaturity of certain tumors, sometimes make it impossible for the pathologist to give a precise diagnosis of the tumor other than the benign or malignant structural character of the lesion. This represents a significant obstacle in hematology for affections which, although non surgical, nevertheless require precise identification of the lesion for effective therapy. The elaboration of more effective sampling material, repeated punctures and immunohistoenzymatic analysis techniques would probably further improve the results of the method.


Asunto(s)
Punciones , Neoplasias Torácicas/diagnóstico , Tomografía Computarizada por Rayos X , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/diagnóstico por imagen , Masculino , Neoplasias del Mediastino/diagnóstico , Neoplasias del Mediastino/diagnóstico por imagen , Persona de Mediana Edad , Neoplasias Pleurales/diagnóstico , Neoplasias Pleurales/diagnóstico por imagen , Neoplasias Torácicas/diagnóstico por imagen
5.
Breast Cancer Res Treat ; 7(2): 105-9, 1986.
Artículo en Inglés | MEDLINE | ID: mdl-3521767

RESUMEN

Between May 1978 and March 1982, 179 postmenopausal women with operable breast cancer were randomized to receive either adjuvant tamoxifen, 40 mg daily for three years (TAM group), or no further treatment (controls). The difference in five-year survival rates (61% in the control group, 72% in the TAM group) was not statistically significant. However, there was a significant improvement in disease-free survival in the TAM group (61%) relative to the controls (44%) (p = 0.008). In estrogen receptor positive patients, tamoxifen improved both the disease-free rate (47% controls, 80% with tamoxifen) and the survival rate (63% to 83%). Similar results were observed in progesterone receptor positive patients. In patients that were estrogen receptor negative, tamoxifen modified neither the survival rate nor the disease-free interval.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Tamoxifeno/uso terapéutico , Neoplasias de la Mama/análisis , Neoplasias de la Mama/cirugía , Ensayos Clínicos como Asunto , Terapia Combinada , Femenino , Estudios de Seguimiento , Humanos , Escisión del Ganglio Linfático , Metástasis Linfática , Mastectomía , Menopausia , Persona de Mediana Edad , Distribución Aleatoria , Receptores de Estrógenos/análisis , Receptores de Progesterona/análisis
6.
Artículo en Francés | MEDLINE | ID: mdl-3546474

RESUMEN

No new general review has appeared concerning the malignant changes that can occur in dermoid cysts of the ovary since the works of Peterson in 1957 and Climie and Heath in 1968. A personal case of epidermoid carcinoma--Stage II B--which occurred in a dermoid cyst gave us the opportunity of reviewing the 132 cases published between 1968 and 1985, which bring the total cases published to more than 400. The cancer arises in 1.78% of mature cystic teratomas. The mean age at diagnosis is 53 years and this pathological change is found five times more frequently after than before the menopause. Before laparotomy is carried out there is no clinical sign nor paraclinical evidence of the diagnosis over and above that of a benign cyst. There are all kinds of histological changes but the epidermoid carcinomas occur in 75% of cases. The survival rate for this kind of ovarian tumour is very poor, with 27% survival after 3 years, taking into account all states and all histological types. Epidermoid carcinomas seem to have a better prognosis than other histological types, and an important prognostic feature is the spread and the ability to remove the tumour surgically when it has extended beyond the capsule of the ovary. Although it is not easy to lay down the best therapy for this condition, by and large extended surgery followed by polychemotherapy or radiotherapy are apparently the only ways of improving the poor prognosis for these tumours.


Asunto(s)
Carcinoma de Células Escamosas/patología , Quiste Dermoide/patología , Neoplasias Ováricas/patología , Adenocarcinoma/patología , Adolescente , Adulto , Anciano , Carcinoma de Células Escamosas/mortalidad , Carcinoma de Células Escamosas/terapia , Niño , Quiste Dermoide/mortalidad , Quiste Dermoide/terapia , Femenino , Humanos , Melanoma/patología , Menopausia , Persona de Mediana Edad , Metástasis de la Neoplasia , Neoplasias Ováricas/mortalidad , Neoplasias Ováricas/terapia , Pronóstico , Factores de Tiempo
7.
Artículo en Francés | MEDLINE | ID: mdl-4031418

RESUMEN

There is now more or less general agreement how to classify and how to work out the development of symmetrical malformations of the female genital tract. On the other hand, asymmetrical malformations, as well as abnormalities of the development of the cervix and the isthmus are only rarely written about in the literature. It has not yet been possible to draw up a system to display the physiopathology and the embryology of these malformations. We here report a rare case of atresia of the cervix and isthmus as well as a pseudo unicornous uterus. This case should take its place as a piece in the embryological puzzle helping to fill in the details which might one day solve this puzzle.


Asunto(s)
Anomalías Múltiples/diagnóstico , Cuello del Útero/anomalías , Útero/anomalías , Anomalías Múltiples/embriología , Amenorrea/diagnóstico , Amenorrea/etiología , Cuello del Útero/embriología , Femenino , Humanos , Persona de Mediana Edad , Útero/embriología
9.
Nephrologie ; 5(2): 59-63, 1984.
Artículo en Francés | MEDLINE | ID: mdl-6483073

RESUMEN

9-hydroxy-2-methyl-ellipticinium (HME) is an intercaling agent mainly potent in metastatic breast cancer. Its almost complete lack of bone marrow toxicity is of greatest value. However, among 385 patients 20 cases of renal failure were observed: renal failure is gradual, non reversible except in four cases with acute renal failure. Histological and ultrastructural studies, performed in 8 cases, showed exclusively proximal tubular lesions, without glomerular or interstitial lesions. We have evidence that there is a relation between the cumulative dose and the severity of the lesions. A prospective study was done in 30 patients. An increase in enzymuria, proteinuria and glycosuria was observed in most patients after HME infusion. HME is an efficient drug in the treatment of bone metastases of breast cancer. Renal function should be carefully monitored during HME administration.


Asunto(s)
Alcaloides/efectos adversos , Antineoplásicos/efectos adversos , Neoplasias de la Mama/tratamiento farmacológico , Elipticinas/efectos adversos , Riñón/efectos de los fármacos , Lesión Renal Aguda/inducido químicamente , Anciano , Elipticinas/uso terapéutico , Femenino , Humanos , Túbulos Renales/patología , Persona de Mediana Edad , Estudios Retrospectivos , Enfermedades Urológicas/inducido químicamente , Enfermedades Urológicas/enzimología
10.
Presse Med ; 12(24): 1527-9, 1983 Jun 04.
Artículo en Francés | MEDLINE | ID: mdl-6222357

RESUMEN

In a period of 18 months, 187 cytology aspiration biopsies of the breast were performed at the Centre François Baclesse by clinicians and radiologists, using the conventional technique. Comparison of the results with clinical, radiological and histological findings by different specialists showed that one out of two aspiration biopsies gave an erroneous diagnosis. The authors believe that this failure was due to the fact that the biopsies were not performed by a cytologist. This prime condition of success should be more clearly expressed in the literature.


Asunto(s)
Neoplasias de la Mama/patología , Biopsia con Aguja/métodos , Biopsia con Aguja/normas , Errores Diagnósticos , Estudios de Evaluación como Asunto , Humanos
12.
Nouv Presse Med ; 7(19): 1652, 1978 May 13.
Artículo en Francés | MEDLINE | ID: mdl-662675

RESUMEN

PIP: The letter reports on 2 cases of hepatic lesions discovered by chance during laparotomy in patients on OCs. Such cases are multiplying all over the world. It would be advisable to systematically perform a biopsy of the liver during laparotomy when the patients have been on OCs, to avoid later, and possibly very serious, problems.^ieng


Asunto(s)
Enfermedad Hepática Inducida por Sustancias y Drogas/patología , Anticonceptivos Orales/efectos adversos , Hígado/patología , Adulto , Biopsia con Aguja , Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Femenino , Humanos , Hígado/efectos de los fármacos
13.
Nouv Presse Med ; 7(7): 545-8, 1978 Feb 18.
Artículo en Francés | MEDLINE | ID: mdl-643580

RESUMEN

The case reported is that of a young woman who underwent a termino-terminal jejno-ileal by-pass procedure for obesity which was refactory to usual forms of treatment. Eight months later, a cholecystectomy was carried out for lithiasis, presenting with abdominal pain. At the time of operation, lesions of cystic pneumatosis were discovered on the excluded length of small bowel. This complication frequently manifests itself in the form of pseudosurgical abdominal pain, or as diarrhoea. More rarly, it is a radiological finding. The pathogenesis remains a subject of discussion. The mechanical theory would seem the most logical, since colonic intraluminal pressure is higher than that in the intestine excluded from the circuit. Bacterial proliferation, classical in blind loops, would be a farourising factor.


Asunto(s)
Íleon/cirugía , Intestino Delgado , Yeyuno/cirugía , Obesidad/terapia , Neumatosis Cistoide Intestinal/etiología , Complicaciones Posoperatorias , Adulto , Femenino , Humanos , Intestino Delgado/patología , Neumatosis Cistoide Intestinal/patología
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