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31.
Antonio López-Beltrán Alfonso S. Calañas Pilar Jimena Alberto L. Escudero Telma R. Campello Manuel Muñoz-Torres Fernando Escobar-Jiménez Rafael E. Carvia F. F. Nogales 《Virchows Archiv : an international journal of pathology》1997,431(2):149-151
Three further cases of mature benign cystic teratomas of the ovary associated with virilization are added to the three previously
reported in the literature. They were found in postmenopausal, obese, diabetic women aged 52, 61, and 67 years. The patients
presented with hirsutism and voice changes and clitoromegaly was present in one. Testosterone and androstenedione levels were
elevated but promptly regressed after removal of the tumours. Histologically, sheets of stromal luteinized cells were found
peripherally at the interface between the neoplasm and ovarian tissue. Luteinization of ovarian stroma induced by an unknown
factor related to diabetes mellitus is the origin of the virilization.
Received: 8 January 1997 / Accepted: 28 February 1997 相似文献
32.
Differential expression of stem cell mobilization-associated molecules on multi-lineage cells from adipose tissue and bone marrow 总被引:68,自引:0,他引:68
De Ugarte DA Alfonso Z Zuk PA Elbarbary A Zhu M Ashjian P Benhaim P Hedrick MH Fraser JK 《Immunology letters》2003,89(2-3):267-270
Our laboratory has characterized a population of stromal cells obtained from adipose tissue termed processed lipoaspirate cells (PLAs). PLAs, like bone-marrow derived mesenchymal stem cells (BM-MSCs), have the capacity to differentiate along the adipogenic, osteogenic, chondrogenic, and myogenic lineages, In order to better characterize these two multi-lineage populations, we examined the surface phenotype of both bone marrow and adipose tissue-derived cells from five patients undergoing surgery. PLA and BM-MSC cells were isolated, subcultivated, and evaluated for cell surface marker expression using flow cytometry. PLA and BM-MSC cells both expressed CD13, CD29, CD44, CD90, CD105, SH-3, and STRO-1. Differences in expression were noted for cell adhesion molecules CD49d (Integrin alpha4), CD54 (ICAM-1), CD34, and CD106 (VCAM-1). While markedly similar, the surface phenotypes of PLA and BM-MSC cells are distinct for several cell adhesion molecules implicated in hematopoietic stem cell homing, mobilization, and proliferation. 相似文献
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de Tommaso M Fiore P Camporeale A Guido M Libro G Losito L Megna M Puca F Megna G 《Neuroscience letters》2003,342(1-2):17-20
The aim of the study was to evaluate the effects of transcutaneous electric nerve stimulation (TENS) on CO(2) laser evoked potentials (LEPs) in 16 normal subjects. The volar side of the forearm was stimulated by 10 Hz TENS in eight subjects and by 100 Hz TENS in the remainder; the skin of the forearm was stimulated by CO(2) laser and the LEPs were recorded in basal conditions and soon after and 15 min after TENS. Both low and high frequency TENS significantly reduced the subjective rating of heat stimuli and the LEPs amplitude, although high frequency TENS appeared more efficacious. TENS seemed to exert a mild inhibition of the perception and processing of pain induced by laser Adelta fibres activation; the implications of these effects in the clinical employment of TENS remain to be clarified. 相似文献
35.
Lorenzo Cecchi Cecchi Lorenzo Marco Morabito Morabito Marco Maria Paola Domeneghetti Domeneghetti Maria Paola Alfonso Crisci Crisci Alfonso Marzia Onorari Onorari Marzia Simone Orlandini Orlandini Simone 《Annals of allergy, asthma & immunology》2006,96(1):86-91
BACKGROUND: Ambrosia pollen is an important allergen in North America and, as recently discovered, in some European countries. In Italy, the most affected area is the northeast, whereas ragweed has not been reported in the central and southern parts of the country. OBJECTIVE: To identify the source of ragweed pollen detected in Florence and Pistoia in central Italy. METHODS: Ragweed pollen data were collected in Florence and Pistoia for a 6-year period (1999-2004). The relationship between pollen counts and local ground prevalent wind directions was evaluated with analysis of variance and the least significant difference test. Weather conditions were also evaluated on a large-scale circulation pattern by analyzing weather maps and air mass back trajectories. RESULTS: A highly statistically significant relationship between daily prevailing wind direction and pollen count was found in the period under investigation; the ragweed pollen peaks were recorded when winds from northeast in Florence and north-northeast in Pistoia were observed. The synoptic weather situation and the path of back trajectories suggest an area around southern Hungary as a possible source of Ambrosia pollen. Furthermore, the pollen count was above the clinical threshold several times in both Florence and Pistoia. CONCLUSIONS: Several factors indicate that the detection of ragweed pollen in central Italy is due to long distance transport. Taking into consideration the high allergenicity of Ambrosia pollen, the present findings, if confirmed, suggest that the number of sensitized individuals might significantly increase in the near future. 相似文献
36.
Teresa Cabrera Maria Angustias Fernandez Angels Sierra Antonio Garrido Alfonso Herruzo Agustin Escobedo Angels Fabra Federico Garrido 《Human immunology》1996,50(2):127-134
We studied 105 tumor samples obtained from patients diagnosed as having breast carcinomas for HLA class I and II (DR) antigen expression, using a panel of mAbs defining HLA-monomorphic, locus-specific and allele-specific determinants. Peripheral blood lymphocytes from patients were also typed for HLA alleles. The results indicated total HLA class I losses in 55 patients (52.3%), HLA-A locus losses in four patients (3.8%), HLA-B locus losses in eight patients (7.6%), and A, B, locus losses in 10 patients (9.5%). The remaining 28 patients whose tissues reacted positively with monomorphic- and locus-specific mAbs were tested for HLA allelic losses using several anti-HLA mAbs defining A2, A3, A9, B8, B12, etc. Of these 28 patients, 16 (57%) showed one or more losses of HLA reactivity. These results indicated that in 88.5% of patients we detected a particular HLA-altered tumor phenotype. The downregulation of HLA class I antigens in breast carcinomas may thus be more frequent than previously reported, and patients without HLA class I downregulation may be the exception rather than the rule. It cannot be ruled out that HLA alterations are present in some of the 12 patients with an apparently normal HLA phenotype, as some HLA alleles could not be studied because of the lack of appropriate mAbs. These HLA alterations could represent an important step associated with tumor invasion, conferring to the tumor cells the ability to escape from T-lymphocyte recognition. 相似文献
37.
L. Doursounian J. M. Alfonso M. T. Iba-Zizen B. Roger E. A. Cabanis V. Meininger H. Pineau 《Surgical and radiologic anatomy : SRA》1989,11(4):313-322
Summary Sagittal sections of the brain-stem made by MRI reveal differences in the angle formed by the medulla and the cord. In order to study the normal mobility of this region of the CNS during flexion and extension of the head, sagittal MRI studies were made in the sagittal plane in 18 young volunteers. The volunteers were in dorsal decubitus with the cervical spine first flexed and then extended, with the movement localized to the cranio-cervical junction as far as possible. T1-weighted sequences were used, with body coils in 16 cases and surface coils in two. Measurements were related to global cranio-cervical range of movement, movement at the craniocervical junction and spino-medullary movement. Variations in the depth of the free space in front of the medulla, pons and spinal cord during movement were also noted. We also checked for downward shift of the lower part of the 4th ventricle and modification of the shape of the ventricle during flexion-extension. The global range of cranio-cervical movement was between 31 and 100° (average 63°). The range between the cranium and C1C2 was 4 to 39° (average 19°) and the spino-medullary range was from 1 to 32° (average 14°). During flexion, the free space narrowed in front of the pons 11 times, in front of the medulla 14 times and in front of the cervical cord 11 times. There was a downward shift of the lower part of the 4th ventricle during flexion in 4 cases but no change in shape was noted. Though this study is open to criticism from several aspects, it may be concluded that variations of the spino-medullary angle in the sagittal plane during flexion-extension do occur, that they are closely correlated with movements at the cranio-cervical junction, and that the spino-medullary junction moves forward during flexion.
Dynamique de la jonction bulbomédullaire et de la moelle cervicale: Étude in vivo dans le plan sagittal en imagerie par résonance magnétique
Résumé Dans le but d'étudier la mobilité normale de la jonction bulbomédullaire durant la flexionextension de la tête, nous avons exploré en IRM dans le plan sagittal 18 jeunes volontaires. L'appareil Magniscan 0,15 Tesla a été utilisé avec des séquences de spin écho courtes, 16 fois en antenne corps et 2 fois en antenne de surface. Dans les limites de notre méthodologie, le secteur global de mobilité cervico-céphalique varie de 31 à 100° (moyenne 63°), le secteur de mobilité O-C1C2 varie de 4 à 39° (moyenne 19°), le secteur de mobilité bulbomédullaire varie de 1 à 32° (moyenne 14°). Lors de la flexion, l'espace libre diminue 11 fois devant la protubérance, 14 fois devant le bulbe et 11 fois devant la moelle cervicale. La partie basse du V4 s'abaisse dans 4 cas en flexion. Aucune modification de la forme du V4 n'a pu être notée. Bien que cette étude soit critiquable à bien des égards, nous pouvons affirmer: que les variations de l'angle bulbomédullaire dans le plan sagittal durant la flexion-extension de la tête sont effectives; qu'elles sont étroitement corrélées à celles de la charnière cranio-rachidienne; que durant le mouvement de flexion, la jonction bulbomédullaire se déplace en avant.相似文献
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39.
Research over the last several decades has led to clear and empirically tractable proposals about the representation of conceptual knowledge in the brain. Here we argue that there are already sufficient data from neuropsychology to strongly constrain extant hypotheses about the representation of conceptual knowledge. One constraint imposed by these neuropsychological data is that recognition of actions and understanding of objects do not necessarily depend on the ability to produce object-associated actions. This conclusion compels a reconsideration of the role played by motor planning and/or execution processes in action and object recognition and understanding. 相似文献
40.