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51.
Thies A Schachner M Berger J Moll I Schulze HJ Brunner G Schumacher U 《The Journal of pathology》2004,203(4):933-939
Aberrant glycosylation is a common feature of metastatic sub-clones of malignant tumours and in uveal melanoma in particular, the HNK-1 glycotope has been positively correlated with poor prognosis. So far, no such correlation has been investigated in cutaneous melanoma. In order to do so, HNK-1 expression was evaluated immunohistochemically in 100 primary cutaneous melanomas and correlated with metastasis after up to 10-years' follow-up. Furthermore, HNK-1 expression was analysed in metastatic deposits (19 distant cutaneous metastases and six sentinel lymph node metastases), as well as in benign nevi. Kaplan-Meier analysis revealed a positive association between HNK-1 expression and metastasis (p < 0.005) and multivariate Cox regression analysis adjusted for the standard prognostic markers ulceration and vertical tumour thickness confirmed HNK-1 expression as an independent prognostic marker. HNK-1 expression was preserved in 42% of the distant cutaneous metastases, but metastatic cells in lymph nodes were devoid of HNK-1 immunoreactivity. None of the benign pigmented lesions exhibited HNK-1 immunoreactivity. Expression of the HNK-1 glycotope in cutaneous malignant melanoma is an independent prognostic marker of metastasis. Differential HNK-1 expression at the metastatic sites implies that its expression is modulated by the surrounding environment. As HNK-1 is also transiently expressed during migration of melanocyte precursor cells derived from the neural crest, recapitulation of this transient expression might occur during metastatic spread of cutaneous malignant melanoma. 相似文献
52.
Summary: In the last 10 years the continuing search for gene function has yielded many mutant mice that unexpectedly showed a complete lack of lymph nodes and/or Peyer's patches. With the realization that all these functionally highly diverse genes are involved at some point in the development of lymphoid organs, the challenge now is to assign a function to the molecules involved in lymphoid organ development. It will be important to determine the sequence of molecular events and assign this to the cellular events that lead to an accumulation of hematopoietic cells in one location, ultimately forming an organized lymphoid organ. Here we will focus on CD45+CD4+CD3– cells that are the early colonizing cells in lymph nodes and Peyer's patches and develop a hypothetical model of their contribution to the creation of organized lymphoid structures. 相似文献
53.
Perceived failure is reported to have detrimental effects on subsequent performance in patients with major depressive disorder. We investigated the error-related negativity (ERN)/error negativity (Ne), an electrophysiological correlate of response monitoring, using a 64-channel EEG. Sixteen patients with DSM-IV major depressive disorder and 16 matched controls participated in an Eriksen flanker task with continuous performance feedback that signaled monetary reward. Compared to controls, patients with major depressive disorder showed a less negative ERN/Ne in error trials following error trials. This result might reflect impaired response monitoring processes in major depressive disorder resulting from an underactivity in a central reward pathway and/or a deficit in strategic reasoning. 相似文献
54.
55.
The Topography of Non-Linear Cortical Dynamics at Rest, in Mental Calculation and Moving Shape Perception 总被引:3,自引:0,他引:3
Andreas Meyer-Lindenberg Ulrike Bauer Stefan Krieger Stefanie Lis Kinga Vehmeyer Georg Schüler Bernd Gallhofer 《Brain topography》1998,10(4):291-299
Differential cortical activation by cognitive processing was studied using dimensional complexity, a measure derived from nonlinear dynamics that indicates the degrees of freedom (complexity) of a dynamic system. We examined the EEG of 32 healthy subjects at rest, during a visually presented calculation task, and during a moving shape perception task. As a nonlinear measure of connectivity, the mutual dimension of selected electrode pairs was used. The first Lyapunov coefficient was also calculated. Data were tested for non-linearity using a surrogate data method and compared to spectral EEG measures (power, coherence). Surrogate data testing confirmed the presence of nonlinear structure in the data. Cognitive activation led to a highly significant rise in dimensional complexity. While both tasks activated central, parietal and temporal areas, mental arithmetic showed frontal activation and an activity maximum at T3, while the moving shape task led to occipital activation and a right parietal activity maximum. Analysis of mutual dimension showed activation of a bilateral temporal-right frontal network in calculation. The Lyapunov coefficent showed clear topographic variation, but was not significantly changed by mental tasks (p<.09). While dimensional complexity was almost unrelated to power values, nonlinear (mutual dimension) and linear (coherence) measures of connectivity shared up to 37% of variance. Data are interpreted in terms of increased cortical complexity as a result of recruitment of asynchronously active, distributed neuronal assemblies in cognition. The topography of nonlinear dynamics are related to neuropsychological and neuroimaging findings on mental calculation and moving shape perception. 相似文献
56.
Georg W. Oertel 《Journal of molecular medicine (Berlin, Germany)》1961,39(9):492-493
Ohne Zusammenfassung 相似文献
57.
Ohne Zusammenfassung 相似文献
58.
Gambichler T Moussa G Sand M Sand D Orlikov A Altmeyer P Hoffmann K 《Journal of biomedical optics》2005,10(6):064030
Noninvasive imaging techniques might be of particular diagnostic value for studying and monitoring cutaneous inflammatory conditions such as contact dermatitis. We evaluate acute allergic contact dermatitis (AACD) by means of optical coherence tomography (OCT) and correlate the clinical grading of patch test reactions with the findings obtained from OCT. Twenty positive patch test reactions (+, n = 6; ++, n = 7; +++, n = 7) are investigated using a conventional OCT scanner. In comparison to the control sites, OCT of AACD showed pronounced skin folds, thickened and/or disrupted entrance signals, and a significant increase in epidermal thickness. Moreover, clearly demarcated signal-free cavities within the epidermis and considerable reduction of dermal reflectivity are demonstrated by OCT. Notably, the latter findings strongly correlate with the clinical patch test grading. OCT may be a useful tool for visualization of micromorphological features of AACD. However, before OCT can be employed as an objective parameter in grading severity of patch test reactions, larger studies are required that correlate clinical patch test readings and OCT findings with histopathology. 相似文献
59.
The mechanisms of cell adhesion to the extracellular matrix (ECM) which are of fundamental importance for function, survival, and growth of cells involve the formation of focal adhesions to facilitate integrin signaling. Recently, it became evident that focal adhesions are not stable but move to enable cell migration and ECM formation. We examined the number, size, and dynamic behavior of focal adhesions in living MG-63 osteoblastic cells, which were cultured on titanium surfaces with different roughnesses and on stainless steel (SS). As a marker for focal adhesions we used GFP-tagged vinculin, a cytoskeletal protein. Focal adhesions were smaller on titanium and on SS than on collagen-coated glass coverslips. The corundum-blasted rough surface of titanium induced the smallest adhesions. On all the surfaces that we have tested, we observed a mobility of focal adhesions. On collagen-coated coverslips focal adhesions moved with a speed of 60 nm/min. The speed was reduced on titanium and still more restricted on SS. The topography did not affect the mobility of focal adhesions. We conclude that on the material surfaces that we have studied a reduced mobility of focal adhesions may strengthen the linkages between cell and ECM but impair the ability to dynamically organize and remodel the ECM. The results may have a great impact in the functional evaluation of tailored biomaterial surfaces for the application in tissue engineering. 相似文献
60.
Georg Brehmer Karl Heinz Hölzer Gerhard Binzus 《Journal of molecular medicine (Berlin, Germany)》1963,41(12):577-580
Zusammenfassung Es wird ein neues Verfahren zur automatischen Untersuchung von Enzymkinetiken angegeben. Die Umsatzgeschwindigkeit einer Enzymreaktion in Abhängigkeit von jeweils einer veränderlichen Größe wird hierbei am durchlaufenden Reaktionsgemisch kontinuierlich gemessen und registriert. Unabhängige Veränderliche kann eine Konzentration (z. B. Substrat-, Coenzym-, Wasserstoffionenkonzentration) oder die Temperatur sein. Am Beispiel der Ermittlung einer Aktivitäts-pS-Kurve (Koordinaten:v=Umsatzgeschwindigkeit;pS=negativer Logarithmus der Substratkonzentration) wird das Verfahren im Einzelnen beschrieben. Unsere Methode eignet sich bisher zur Untersuchung von Enzymen, deren Umsatz durch Messung der Lichtabsorption erfaßbar ist. Als Beispiel werden Aktivitäts-pS-Kurven von Lactatdehydrogenase aus menschlichem Herzmuskel- und Leberhomogenisat sowie von Kaninchenmuskel-LDH gezeigt und die ermittelten Michaeliskonstanten angegeben. 相似文献