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71.
72.
We previously conducted a study of 88 cases of prostate cancer in an attempt to identify potential prognostic biomarkers that can distinguish aggressive cases that must be treated immediately. Prostate cancer is a serious disease affecting men worldwide and compromises the quality of life of its patients. Biomarkers studied included chromosome 7 trisomy, chromosome 8 trisomy, and HER-2/neu oncogene amplification. These biomarkers were initially studied because trisomy 8 and oncogene amplification of the HER-2/neu gene have been reported in many other cancers, including those studied in this laboratory. In view of the fact that HER-2/neu amplification was not found to play a prominent role in the group of prostate cancer specimens that we studied, an exploration of other biomarkers was felt to be warranted. Thus, we began a pilot study of c-myc oncogene copy number in prostate cancer using the same protocol for fluorescent in situ hybridization and a direct-labeled SpectrumOrange LSI c-myc probe (Vysis, Inc., Downers Grove, IL) on formalin-fixed, paraffin-embedded tissue. From a total of 36 cases of prostate cancers successfully analyzed, we found 11 (31%) tumors exhibiting 3 or more positive signals for c-myc in 15% or more of the cells. Of these, only 7 tumors (19% of the total cases studied) had >/=3 signals in 20% or more of the cells. No case had >/=3 signals in 25% or more of the cells. Compared to other molecular probes tested, the c-myc signals were more faint and the quality of the preparation was less optimal than other tumor specimens that we previously studied. Based on the information available thus far, we conclude that an increased copy number in c-myc oncogene copy number was not a prominent finding in our cohort of prostate cancer patients.  相似文献   
73.
AIMS: Three cases with features of so-called 'Warthin-like tumour' of the thyroid (WaLTT) are described, in order to evaluate its relationship with papillary carcinoma (PC). METHODS AND RESULTS: We performed an histological and immunohistochemical study with emphasis on RET/PTC expression. The most striking features are represented by marked lymphocytic infiltration in the stalks of papillae and by oxyphilic metaplasia of epithelium, resembling Warthin tumour of the salivary gland. In all cases, we found nuclear features reminiscent of PC. The neoplastic cells were strongly positive for Leu M1 and epithelial membrane antigen (EMA), less for thyroglobulin and negative for calcitonin. The lymphocytic infiltrate was composed of a mixed population of B and T-cells with sparse S100-positive Langerhans cells. An interesting finding was the strong positivity with the antibody against RET/PTC. CONCLUSION: All clinicopathological data along with the presence of the extensive lymphocytic infiltrate could imply a more favourable prognosis. The expression of RET/PTC fusion gene adds support to the hypothesis that this tumour is a variant of PC, probably related to the oncocytic variant of PC.  相似文献   
74.
A retroviral element (MSRV) defining a family of genetically inherited endogenous retroviruses (HERV-W) has recently been characterized in cell cultures from patients with multiple sclerosis (MS). To address the possible relationship with MS, direct detection of circulating virion RNA was proposed but revealed technically difficult to perform in standardized conditions, in the face of multiple endogenous HERV-W copies. A parallel approach has evaluated MSRV potential pathogenicity in relation to characteristic features of multiple sclerosis, in particular, T-lymphocyte-mediated immunopathology. We report here that MSRV particles induce T-lymphocyte response with a bias in the Vbeta16 chain usage in surface receptor, whatever the HLA DR of the donor. A recombinant MSRV envelope-but not core-protein reproduced similar nonconventional activation. Molecular analysis of Vbeta CDR3 showed that Vbeta16 expansions are polyclonal. Our results thus provide evidence that MSRV envelope protein can trigger an abnormal immune response with similar characteristics to that of superantigens.  相似文献   
75.
76.
Human T lymphocyte subsets, identified by means of OKT3, 4 and 8 monoclonal antibodies, were isolated by a fluorescence activated cell sorter (FACS IV) and analyzed for distribution of alpha-naphthyl acetate esterase (ANAE) activity. As compared to OKT8+ lymphocytes a higher proportion of OKT4+ lymphocytes was ANAE-positive exibiting a spot or dot-like pattern in the cytoplasm. OKT8 and 4 positive subsets showed a similar ANAE distribution in diffuse granular form. Although OKT4 and OKT8 populations presented a different ANAE dot-like reactivity, this marker did not allow as clear a distinction between them as that reported for TG and TM lymphocytes.  相似文献   
77.
Summary The authors have reported on the prognostic value of continuous monitoring of somatosensory evoked potentials (SEP) in a survey of 25 patients who underwent carotid surgery. SEP recordings were correlated with the EEG, stump pressure (SP) values and clinical outcome. A non-cephalic reference was used for SEP recordings to allow the analysis of both subcortical and cortical components. During surgery the conduction time between SEP peaks relating to the subcortical components remained stable or showed minimum variations in all patients. During carotid clamping, SEP variations were observed in 9 out of 25 cases (36%). The application of an intraluminal shunt was accompanied by the return to normal values in 7 out of 9 patients. In the remaining two cases SEP abnormalities continued post-operatively and were accompanied by new neurological deficits. EEG changes during carotid clamping were associated with SEP modifications in 6 out of 7 cases, although they were not always correlated. Results confirm that SEP recordings provide useful data concerning the function of the CNS in anaesthetized patients and that, being sensitive to CBF changes, SEP monitoring acts as an indicator of cerebral ischaemia.Presented in part at the Third International Evoked Potentials Symposium, Berlin-West, September 28th–October 1st, 1986.  相似文献   
78.
Summary Anterior displacement of the mandible (ADM) was performed in 34 patients undergoing surgery for malformations or atheromatous lesions of the distal segment of the extracranial internal carotid artery (ICA). This procedure greatly facilitates surgical access to the upper cervical region and has several advantages over mandibulotomy-mandibulectomy, namely: A shorter operating time, sparing of the inferior alveolar nerve and of the mandibular branch of cranial nerve VII, with no need for post-operative immobilization of the mandible. ADM permits the correction of ICA lesions extending as far as the first cervical vertebra. For lesions extending into the carotid canal ADM needs to be supplemented by various other procedures via the base of the skull.  相似文献   
79.
The sensitivity of preoperative imaging was evaluated for the localization of insulinomas in 2 series of 54 and 17 patients, respectively. In the first series, diagnosis was obtained with ultrasonography (US) in 14.8%, with computed tomographic (CT) scan in 60%, and with arteriography and/or angio CT scan in 75% of patients. In the second series, US, CT scan, and arteriography were performed preoperatively showing a sensitivity of 53% of one or more of the imaging techniques. The last 17 patients all underwent intraoperative pancreatosonography, and the insulinoma was localized in each. Considering the high reliability of intraoperative ultrasonography, and the high costs and low benefits of other current diagnostic techniques, a new management plan is suggested for patients with a definite laboratory diagnosis of insulinoma.
Resumen La sensibilidad de la imagenología preoperatoria para la localización de insulinomas fue evaluada en 2 series de 54 y 17 pacientes respectivamente. En la primera serie, el diagnóstico fue logrado con ultrasonografía en 14.8%, con escanografía computadorizada en 60%, y con arteriografía y/o angiografía con escanografía computadorizada en 75% de los casos. En la segunda serie, la ultrasonografía, la escanografía computadorizada, y la arteriografía fueron realizadas preoperatoriamente demostrando una sensibilidad de 53% en una o más de las técnicas de imagenología. En los últimos 17 pacientes se realizó pancreatosonografía, la cual permitió la localización del tumor en 100% de los casos.En consideración a la elevada confiabilidad de la ultrasonografía intraoperatoria, y los altos costos y bajo rendimiento de las técnicas corrientes de diagnóstico, se sugiere un nuevo plan de manejo para pacientes con un diagnóstico de laboratorio certero de insulinoma. Se fundamenta en la localización ultrasonográfica intraoperatoria del tumor, la cual puede ser aplicada en los más comprensivos centras médicos.

Résumé La sensibilité de l'imagerie pré-opératoire permettant la localisation des insulinomes a été étudiée dans 2 séries de 54 et 17 sujects. Dans la première série le diagnostic fut posé par l'échographie dans 14.8% des cas, par la tomodensitométrie dans 60% des cas, par l'artériographie et/ou l'angiotomodensitométrie dans 75% des cas. Dans la seconde série, l'échographie, la tomodensitométrie et l'artériographie furent pratiquées avant l'intervention avec une sensibilité de 53% pour l'une ou pour plusieurs techniques. Chez les 17 derniers malades l'échographie opératoire fut systématiquement pratiquée et permit la localisation de la tumeur dans 100% des cas.Considérant la haute fiabilité de l'échographie opératoire, le coût élevé et les faibles résultats des autres techniques de diagnostic, un nouveau plan d'investigation est proposé pour explorer les malades qui présentèrent certains signes biologiques d'insulinome. Il repose sur la localisation per-opératoire de la tumeur par l'échographie, méthode qui peut être pratiquée dans des centres spécialisés.
  相似文献   
80.
The cirrhotic condition is characterized by a series of changes in physiological functions and of subclinical alterations that imply an abnormal and fragile adaptive pattern with reduced resistance to superimposed distress. In the care of the critically ill cirrhotic patient, the supportive measures aimed at maintaining physiological stability through the control of such debilitating factors have a key role and are not secondary in importance to the more obvious measures needed to treat clinically evident and specific alterations or complications. The relationship between hepatic malfunction and the development of these physiological abnormalities is not fully understood. Our knowledge of the problem, however, has been recently improved and the need for supportive measures motivated by a series of notions on cardiorespiratory and metabolic abnormalities and interactions in hepatic decompensation.
Resumen La condición cirrótica se caracteriza por una serie de cambios en las funciones fisiológicas y por alteraciones subclinicas que implican un patrón de adaptación anormal y fragil de resistencia reducida al estrés. Estas incluyen disfunción respiratoria con tendencia a la hipoxemia arterial en presencia de elevados indices cardiacos, una situatión crónica de hiperdinamismo cardiovascular pero con precaria eficacia miocárdica y latente riesgo de falla de alto débito, y cambios metabólicos que se traducen en un estado de fallas multisistémicas interrelacionadas características del cirrótico. En el cuidado del paciente cirrótico en estado crítico, las medidas de soporte orientadas al mantenimiento de la estabilidad fisiológica mediante el control de tales factores debilitantes tienen una importancia capital y no son secundarias frente a aquellas muy obvias que se requieren para tratar alteraciones o complicaciones específicas y clínicamente evidentes. La relación entre la disfunción hepática y el desarrollo de las mencionadas anormalidades fisiológicas no está totalmente aclarada, sin embargo, el estado de nuestro conocimiento sobre el problema ha sido enriquecido recientemente y se ha fortalecido la necesidad de establecer medidas de soporte por una serie de nociones relativas a las anormalidades e interacciones cardiorrespiratorias y metabólicas de la descompensación hepática.

Résumé La cirrhose est caractérisée par des séries de variations des fonctions physiologiques et de modifications cliniques qui impliquent des modalités d'adaptation anormale et fragile se traduisant par une résistance réduite à l'état de détresse ou peut se trouver le cirrhotique. Des mesures appropriées pour maintenir la stabilité physiologique ont un rôle principal en présence de ces facteurs défavorables. Elles ne doivent pas être considérées comme moins importantes que les mesures essentielles qui sont nécessaires pour traiter les complications et les modifications cliniques spécifiques. La relation entre l'altération des fonctions du foie et le développement des anomalies physiologiques précitées n'est pas parfaitement élucidée, cependant, nos connaissances de ce problème ont été récemment améliorées et le besoin de mesures adéquates de soutien est devenu manifeste en raison de séries acquises de notions concernant les anomalies cardio-respiratoires et métaboliques ainsi que les interactions de la décompensation hépatique.
  相似文献   
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