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991.
La Seta F Buccellato A Albanese M Barbiera F Cottone M Oliva L Agricola A Costanzo GS Lagalla R 《La Radiologia medica》2004,108(5-6):515-521
PURPOSE: To evaluate the current role of small bowel (SB) radiologic barium examinations in adult celiac disease (ACD). MATERIALS AND METHODS: Retrospective review of 61 SB barium examinations in 280 ACD patients. Sixty-one examinations in 61 patients were performed: 7/61 with small bowel 'follow-through' (SBFT) method, and 54/61 with small bowel double-contrast enteroclysis (SBE). Radiological criteria for ACD diagnosis were divided in four groups: 1) definite ACD (reversal of jejuno-ileal fold pattern); 2) possible ACD (malabsorption pattern and ileal jejunization); 3) malabsorption (fluid, dilatation, 'moulage', flocculation); 4) complicated ACD (irregular, thickened, nodular folds; wall thickening; masses). RESULTS: In 49/61 patients RX examinations were performed before ACD diagnosis. In this group, clinical presentations included one or more of the following: diarrhea, weight loss, malabsorption, anemia, abdominal pain; 7/49 had a SBFT, and 42/49 a SBE. All 7 SBFTs showed pattern 3, and 8/42 SBEs showed pattern 2 (suspected ACD). In 34/42 patients SBE allowed a definite ACD diagnosis (pattern 1); however, 6/34 were also false-positive for complicated ACD (pattern 4). Ten out of sixty-one patients were clinically suspected of having complicated ACD, correctly excluded (8/8) or confirmed (2/2) by SBE. None of these 59/61 patients had a radiologic diagnosis of normal' SB. The last 2/61 patients with ACD, examined for persisting chronic anemia, had a normal SBE. CONCLUSIONS: This study confirm that SB radiology may be of value either in ACD diagnosis or in excluding complications: SBE is currently the most accurate examination. SBE alone is however less accurate in confirming complicated ACD; further imaging techniques are always needed in this clinical context. 相似文献
992.
Ortiz S Oliva JM Pérez-Rial S Palomo T Manzanares J 《Alcohol and alcoholism (Oxford, Oxfordshire)》2004,39(2):88-92
AIMS: The aim of this study was to examine the effects of chronic ethanol consumption in cannabinoid CB(1) receptor gene expression in Wistar rats. METHODS: Rats were exposed to a bottle containing a solution of ethanol (10% v/v) and saccharin (0.25% w/v) for 52 days. At the end of this period, rats were killed by decapitation and cannabinoid CB(1) receptor gene expression was measured by in situ hybridization histochemistry. RESULTS: Our results indicated that chronic ethanol consumption reduced cannabinoid CB(1) receptor gene expression in caudate-putamen (CPu) (24%), ventromedial nucleus of the hypothalamus (VMN) (43%), CA1 (27%) and CA2 (22%) fields of hippocampus and increased dentate gyrus (DG) (30%). CONCLUSIONS: These results reveal for the first time that prolonged exposure to ethanol produces marked alterations in cannabinoid CB(1) receptor gene expression in selected regions of the rat brain, supporting an interaction between ethanol consumption and the endogenous cannabinoid receptor. Furthermore, these findings suggest that cannabinoid CB(1) receptor may be considered as a new pharmacological target for treating ethanol dependence. 相似文献
993.
Nano R Barni S Chiari P Pinelli T Fossati F Altieri S Zonta C Prati U Roveda L Zonta A 《Oncology reports》2004,11(1):149-153
The effect of neutron boron capture therapy (BNCT) was studied in rat tumor liver cells after induction of the liver metastases by splenic inoculation of cells from DHA/K12/TRb line. Ten days following the treatment, the BPA was injected into rats and therefore the animals were sacrificed, the liver was exposed to neutron irradiation and processed. In some experiments the liver was reimplanted (after irradiation) in syngenic animals and studied 3 days later, following sacrifice. Samples of tissue obtained from metastasised and non-metastasised areas of the liver parenchyma, before and after the neutron irradiation, were examined in light microscopy and electron microscopy. The analysis pointed out damages induced by the neutron treatment in single tumor cells mostly localised in the synusoidal blood stream. Debris and apoptotic cells were sometimes observed in the neoplastic nodules before treatment, while the tumor cell death (apoptosis) increased in the tumor cells following BNCT treatment. An intense scavenger activity of Kupffer cells after irradiation was accompanied by a strong acid phosphatase reaction detectable in wide cytoplasmic areas. In the liver parenchyma of reimplanted animals, the presence of large collagen bundles spread among the hepatocytes was observed at electron microscopy. 相似文献
994.
Avilés A Fernándezb R Pérez F Nambo MJ Neri N Talavera A Castañeda C González M Cleto S 《Leukemia & lymphoma》2004,45(7):1385-1389
The role of adjuvant radiotherapy to sites of nodal bulky disease in patients with aggressive diffuse large cell lymphoma (DLCL), and stage IV remain undefined. We began a prospective controlled clinical trial to evaluate impact in event free survival (EFS) and overall survival (OS) in a large cohort of patients with a longer follow-up. Between 1989 and 1995; 341 patients with aggressive DLCL and presence of nodal bulky disease (tumor mass > 10 cm) in pathological proven complete response after intensive chemotherapy were randomized to received either radiotherapy (involved fields, 40 Gy) or not. The 5-year EFS and OS in radiated patients were respectively: 82% (95% Confidence interval (CI): 70-89%) and 87% (95% 80-99%), that were statistically significant to control group: 55% (41-64%) (P < 0.001) and 66% (95% CI: 51-73%) (P < 0.01) respectively. Radiotherapy was well tolerated, acute toxicity was mild and until now late toxicity did not appear. The use of adjuvant radiotherapy improve EFS and OS and probably the possibility of cure in patients diffuse large cell lymphoma with worse prognostic factors. Thus, we felt that adjuvant radiotherapy will be considered as part of the initial treatment in this setting of patients. 相似文献
995.
Cristina Corzo Contero Ignacio Tusquets Trias de Bes Marta Salido Galeote Josep Maria Corominas Torres Berta Laquente Saez Meritxel Bellet Ezquerra Xavier Fabregat Mayol Sergio Serrano Figueras Francesc Solé Ristol 《Clinical & translational oncology》2004,6(5):289-294
Background
HER2/neu encodes a receptor related to breast cancer pathogenesis and topoisomerase IIα is an enzyme involved in response to anthracycline chemotherapy. The aim of this study is to analyse HER2/neu and topoisomerase IIα in a homogenous series of 49 patients with locally-advanced breast cancer (LABC) to determine their status and predictive value with respect to response to treatment.Material and methods
Paraffin-embedded tissues samples from patients with LABC (prior to their neoadjuvant chemotherapy programme) were analysed using the FISH technique.Results
HER2 amplification was noted in 29% of cases of which 77% presented amplification in the topoisomerase IIα gene, 15% had deletion and 8% did not show any aberration in topoisomerase IIα status.Conclusions
These preliminary analyses show a correlation between HER2 amplification and topoisomerase IIα status (92%), and suggest that patients with non-amplified HER2/neu or topoisomerase IIα have better response and have and increase (albeit not statistically significant) in disease-free survival (DFS). However, the limited numbers of patients in the study preclude definitive conclusion regards the value of these genes in predicting patient response to anthracycline-based chemotherapy. 相似文献996.
We propose that the age-related accumulation of deltamtDNA(4977) mutations may serve a protective function against tumor-promoting effects of other somatic mutations. The evidence discussed here is consistent with the concept that deltamtDNA(4977) plays a tumor-suppressor role, thus shedding new light to the concept of a tumor suppressor mutation. This concept may help understand how a tumor-promoting mutation may be able to cause malignant transformation in cells lacking a tumor-suppressor mutation, while the same tumor-promoting mutation can be present in cells that carry a tumor-suppressor mutation, without causing cancer. 相似文献
997.
The Taenia crassiceps cysticercus is a cestode that naturally and experimentally infects rodents in which it reproduces by budding. In the laboratory, a persistent cellular immunosuppression with a concomitant increasing load of parasites has been observed in experimentally infected BALB/cAnN mice. In this study, enhanced apoptosis was found in spleen cells from 30-day infected mice with a typical "ladder-patterned" DNA fragmentation and an increase in phosphatidylserine expression. A characteristic poly-(ADP-ribose) polymerase cleavage indicates that this cell death is caspase-mediated. Apoptosis was detected in the CD4(+) and CD19(+) splenocytes of infected mice after in vitro stimulation with cysticercal antigens. Considering previous results on the crucial role that CD4(+) T cells play in controlling the extent of infection, apoptosis in this T-lymphocyte subpopulation induced by T. crassiceps cysticerci could be responsible for the immunosuppression that underlies parasite success. 相似文献
998.
Oehninger S Morshedi M Weng SL Taylor S Duran H Beebe S 《Reproductive biomedicine online》2003,7(4):469-476
Ejaculated spermatozoa, particularly in infertile men, have been shown to display morphological and biochemical features that are typical of an apoptotic phenotype in somatic cells. Deregulation of apoptosis is known to play roles in a number of disease processes, but roles for apoptosis in ejaculated spermatozoa and male infertility are poorly defined or have not been studied. Preliminary data demonstrated that populations of ejaculated spermatozoa express: (i) various degrees of plasma membrane translocation of phosphatidylserine and DNA fragmentation; and (ii) active caspase-3, the main executor of apoptosis in somatic cells, with an apparent exclusive cellular location to the mid-piece. Tests are currently being carried out on the effects of well-known apoptosis agonists and caspase inhibitors on such markers using purified populations of leukocyte-free ejaculated human spermatozoa. The main objective is to determine if somatic cell apoptosis markers are relevant indicators and/or causative factors of male infertility. 相似文献
999.
We report here the activity of 96 cells in primate primary motor cortex (MI) during exertion of isometric forces at the hand in constant spatial directions, while the hand was at five to nine different spatial locations on a plane. The discharge of nearly all cells varied significantly with both hand location and the direction of isometric force before and during force-ramp generation as well as during static force-hold. In addition, nearly all cells displayed changes in the variation of their activity with force direction at different hand locations. This change in relationship was often expressed in part as a change in the cell's directional tuning at different hand locations. Cell directional tuning tended to shift systematically with hand location even though the direction of static force output at the hand remained constant. These directional effects were less pronounced before the onset of force output than after force onset. Cells also often showed planar modulations of discharge level with hand location. Sixteen proximal arm muscles showed similar effects, reflecting how hand location-dependent biomechanical factors altered their task-related activity. These findings indicate that MI single-cell activity does not covary exclusively with the level and direction of net force output at the hand and provides further evidence that MI contributes to the transformation between extrinsic and intrinsic representations of motor output during isometric force production. 相似文献
1000.
G12S and H50R variations are polymorphisms in the SDHD gene 总被引:1,自引:0,他引:1
Cascón A Ruiz-Llorente S Cebrián A Letón R Tellería D Benítez J Robledo M 《Genes, chromosomes & cancer》2003,37(2):220-221