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Chatelain D Devendeville A Rudelli A Bruniau A Geslin G Sevestre H 《Archives of pathology & laboratory medicine》2004,128(5):568-570
We report a case of gastric myeloid metaplasia in an 89- year-old woman with agnogenic myeloid metaplasia. The lesions were fortuitously discovered on upper endoscopy. The antral mucosa was thickened and polypoid, and on histologic examination contained immature granulocytes, megakaryocytes, and a few erythroblasts without desmoplastic stromal reaction. The granulocytes were positive for CD15, CD68, and myeloperoxidase on immunohistochemistry, and the megakaryocytes showed positive reactivity for factor VIII. Gastric myeloid metaplasia is a very rare event, and to our knowledge only 6 cases have been reported in the literature to date. It usually occurs in patients with advanced myeloproliferative syndrome. Gastric myeloid metaplasia often has a pseudotumoral appearance, leading to digestive symptoms. Histologic diagnosis is straightforward when trilinear hematopoietic elements are identified in gastric biopsies. Immunohistochemistry with anti-factor VIII antibody can be useful to confirm the presence of megakaryocytes. 相似文献
23.
Fabrice Bonnet Anne-Christine Jouvencel Marie Parrens Magali Joblon Leon Emmanuelle Cotto Isabelle Garrigue Philippe Morlat Jacques Beylot Hervé Fleury Marie-Edith Lafon 《Journal of clinical virology》2006,36(4):258-263
BACKGROUND: Epstein-Barr virus (EBV) may be causally associated with non-Hodgkin Lymphoma (NHL) in HIV-infected patients. OBJECTIVES: To compare EBV load in whole blood in AIDS-NHL patients, HIV non-AIDS patients and non-HIV-infected persons, and to prospectively measure EBV load in whole blood in AIDS-NHL patients. STUDY DESIGN: Longitudinal and prospective study. RESULTS: We observed no statistical difference in EBV load between AIDS-NHL (3.69log(10) copies/mL [interquartile range (IQR): 2.89-4.27]) and HIV non-AIDS patients (3.08log(10) copies/mL [IQR: 1.29-3.57]) but AIDS-NHL patients had significantly higher EBV loads than HIV-negative controls (1.19log(10) copies/mL [IQR: 0.00-3.29]). We noticed an inverse correlation between CD4+ lymphocytes count and EBV load in patients with AIDS-NHL (r(2)=0.41, P=0.01). In the longitudinal study, the mean EBV load three months after NHL diagnosis decreased significantly (mean difference=-1.69log(10) copies/mL [95% confidence interval: -0.32; -3.04]; P=0.03) under chemotherapy but was still elevated in patients with relapses or no response to chemotherapy. CONCLUSION: Although EBV load seems a suboptimal marker for the diagnosis of AIDS-NHL, we observed a significant decrease of EBV load in patients treated with chemotherapy and a strong association between NHL outcome and EBV load in whole blood. 相似文献
24.
Zusammenfassung Die CT ist nach neoadjuvanter Radio-Chemo-Therapie zur Charakterisierung der Tumorregression nur begrenzt einsetzbar. Daher sollte die Wertigkeit der 18F-FDG-PET als molekulares, nichtinvasives bildgebendes Verfahren analysiert werden.Bislang 32/100 Patienten mit NSCLC Stadium IIIA/IIIB wurden in einer multizentrischen, randomisierten Therapiestudie (LUCAS-MD) untersucht. Prätherapeutisch erfolgten eine 18F-FDG-PET und eine Spiral-CT. Der neoadjuvante Therapieblock bestand aus 2–3 Zyklen Paclitaxel und Carboplatin sowie einer simultanen Radio-Chemo-Therapie. Es folgte eine zweite PET direkt vor der Operation mit Bestimmung des Glukosemetabolismus für Primärtumor und Lymphknotenmetastasen sowie eine PET-CT-Bildfusion. Der am OP-Präparat bestimmte Regressionsgrad wurde mit den PET-Befunden und dem Überleben der Patienten korreliert.In Lymphknoten von 10 Patienten mit kompletter Remission in der FDG-PET zeigte sich ein Regressionsgrad/RG III im OP-Präparat (Sensitivität 100%). Zu 94% wiesen die 16/32 Patienten mit kompletter Remission im Primärtumor RG IIb oder III auf, ein Patient RG IIa (falsch-negativ). Die Zweijahresüberlebenswahrscheinlichkeit bei kompletter Remission war nach 24 Monaten signifikant erhöht (76 vs. 20%, p=0,0079). Patienten mit RG III bzw. IIb lebten signikant länger als Patienten mit RG IIa bzw. I (63 vs. 36%, p=0,0123).Der RG korreliert mit der in der FDG-PET bestimmten metabolischen Remission. Die PET eilt metabolisch dem durch die CT bestimmten Tumoransprechen nach neoadjuvanter Behandlung deutlich voraus und ermöglicht wahrscheinlich eine prospektive Aussage über den Langzeittherapieerfolg von Patienten mit NSCLC im Stadium III. 相似文献
25.
The error negativity, an EEG wave observed when subjects commit an error in a choice reaction time (RT) task, is often considered as a sign of error detection. Recently, reports of Ne-like waves on correct responses did challenge this interpretation. It has been proposed, however, that these Ne-like waves result either from an artifactual contamination of response-locked activities by stimulus-locked ones, or from an implicit monitoring of the time elapsing during the RT. Our aim was to reprocess published data: (1) to compare the shape and amplitude of EMG-locked and stimulus-locked ERPs on correct trials, and (2) to compare the size of the EMG-locked Ne-like waves obtained on fast and slow trials. The results neither support the artifact hypothesis nor the RT monitoring one. Therefore, it seems that the Ne-like waves observed on correct trials do correspond to a Ne, which suggests that the Ne has a broader significance than just error detection. 相似文献
26.
Identification of iduronate sulfatase gene alterations in 70 unrelated Hunter patients 总被引:4,自引:0,他引:4
Roseline Froissart Irène Maire Gilles Millat Stéphane Cudry Anne-Marie Birot Véronique Bonnet Olivier Bouton Dominique Bozon 《Clinical genetics》1998,53(5):362-368
We studied 70 unrelated Hunter patients and found a gene alteration in every patient. The molecular heterogeneity was very important. Large gene rearrangements were identified in 14 patients. Forty-three different mutations were identified in the 56 other patients and 31 were not previously described. Deletions and insertions, splice site mutations were associated with a severe phenotype as nonsense mutations except Q531X. Only a few mutations were present in several patients making difficult genotype-phenotype correlations. Mutation identification allows accurate carrier detection improving prenatal diagnosis. The mother was not found to be a carrier in five cases among the 44 sporadic cases. Haplotype analysis demonstrated a higher frequency of mutations in male meiosis. 相似文献
27.
It was hypothesized that the metabolic effects of caffeine, which can be objectively measured (i.e. physiological, "arousal"), could be used to develop a physiological arousal model of chronic insomnia in a group of normal young adults. Twelve normal young adult males participated for 11 nights after laboratory adaptation. Subjects received 400 mg of caffeine three times a day for 7 nights and days. As predicted, the use of caffeine resulted in increased metabolic rate. Sleep efficiency was significantly reduced by caffeine and multiple sleep latency tests (MSLTs) were significantly increased. Some adaptation to the metabolic, sleep efficiency, and MSLT effects of caffeine was seen over the week of administration. Withdrawal effects (i.e. rebound sleep or sleepiness) were not seen for metabolic, MSLT or sleep variables. The data indicated that caffeine was effective in producing significant metabolic and sleep effects and that those effects were related. The results were consistent with the interpretation that a chronic decrease in sleep efficiency associated with increased physiological arousal, although producing subjective dysphoria, does not produce a physiological sleep debt. 相似文献
28.
29.
Functional mapping of the human globus pallidus: contrasting effect of stimulation in the internal and external pallidum in Parkinson's disease 总被引:4,自引:0,他引:4
Yelnik J Damier P Bejjani BP Francois C Gervais D Dormont D Arnulf I M Bonnet A Cornu P Pidoux B Agid Y 《Neuroscience》2000,101(1):77-87
Our objective was to elaborate a functional map of the globus pallidus by correlating the intrapallidal localization of quadripolar electrodes implanted in parkinsonian patients with the clinical effect of the stimulation of each contact. Five patients with L-DOPA-responsive Parkinson's disease presenting severe motor fluctuations and L-DOPA-induced dyskinesias were treated by continuous bilateral high-frequency stimulation of the globus pallidus. The effects of stimulation on parkinsonian disability were tested through each of the four stimulating contacts of each electrode. The anatomical localization of each of the stimulating contacts was determined by confronting the pre- and post-operative magnetic resonance imaging with the anatomical atlas of Schaltenbrand and Wharen.(34) The registration procedure comprised digitization of the atlas, the use of deformation tools to fit atlas sections with magnetic resonance imaging sections, and three-dimensional reconstruction of both the atlas and the magnetic resonance imaging sections. Analysis of the 32 stimulating contacts tested did not reveal a somatotopic organization in the pallidal region investigated but demonstrated that high-frequency stimulation had contrasting effects depending on whether it was applied to the external or the internal pallidum. Akinesia was improved by stimulation of the external pallidum but worsened by stimulation of the internal pallidum. In contrast, parkinsonian rigidity was improved by stimulation of either part of the pallidum. The areas in the internal pallidum where stimulation worsened akinesia were those in which stimulation reduced or suppressed L-DOPA-induced dyskinesias. Conversely, stimulation applied to the external pallidum induced dyskinesias. The fact that rigidity was improved by stimulation of the internal and external pallidum suggests that the neuronal bases of parkinsonian rigidity are different from those of akinesia and dyskinesias. The effect on akinesia and dyskinesias is in agreement with the current model of basal ganglia circuitry(10) if high-frequency stimulation activates rather than inhibits pallidal neurons, a possibility which is very likely since there are marked anatomical, biochemical and electrophysiological differences between the globus pallidus and the subthalamic nucleus.This study demonstrates that high-frequency stimulation of the globus pallidus in parkinsonian patients has contrasting effects depending on whether it is applied to the external or the internal part of this nucleus. The effect on akinesia and dyskinesias suggests that stimulation activates pallidal neurons, a result which challenges the generally accepted concept that high-frequency stimulation inactivates neurons in the region stimulated. 相似文献
30.