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排序方式: 共有6583条查询结果,搜索用时 15 毫秒
21.
Trisomy 8 in myelodysplasia and acute leukemia is constitutional in 15-20% of cases. 总被引:2,自引:0,他引:2
Emanuela Maserati Fiorenza Aprili Fabrizio Vinante Franco Locatelli Giovanni Amendola Adriana Zatterale Giuseppe Milone Antonella Minelli Franca Bernardi Francesco Lo Curto Francesco Pasquali 《Genes, chromosomes & cancer》2002,33(1):93-97
The trisomy 8 found in malignancies may derive from a constitutional trisomy 8 mosaicism (CT8M), and in these cases the trisomy itself may be regarded as the first mutation in a multistep carcinogenetic process. To assess the frequency of CT8M in hematological dysplastic and neoplastic disorders with trisomy 8, an informative sample of 14 patients was collected. The data ascertained included chromosome analyses of fibroblast cultures and of PHA-stimulated blood cultures in patients with normal blood differential count, as well as possible CT8M clinical signs. One patient showed trisomy 8 in all cell types analyzed and undoubtedly has a CT8M; a second patient consistently showed trisomy 8 in PHA-stimulated blood cultures when no immature myeloid cells were present in blood and should be considered as having CT8M; a third patient, with Philadelphia-positive chronic myelocytic leukemia, was more difficult to interpret, but the possibility that she had CT8M is likely. A few clinical signs of CT8M were also present in these three patients. Our data indicate that the frequency of CT8M in hematological dysplastic and neoplastic disorders with trisomy 8 is approximately 15-20%. 相似文献
22.
Silvia Natoli Marco Ciotti Pierpaolo Paba Gian Piero Testore Giampiero Palmieri Augusto Orlandi Alessandro Fabrizio Sabato Francesca Leonardis 《Journal of clinical virology》2006,37(1):72-74
BACKGROUND: Lethal varicella in immunocompetent hosts is rare and its pathogenesis is largely unknown. The discovery of glycoprotein E (gE) mutants showing attributes consistent with increased virulence in vitro and in animal models, provided a possible molecular mechanism underlying a more aggressive virus infection. However, these mutants have never been associated with unusually severe clinical cases. OBJECTIVES: To varicella-zoster virus (VZV) mutations that correlate with increased virulence. RESULTS: We report a case of fatal hepatitis caused by a VZV bearing a novel mutation on the 3B3 monoclonal antibody epitope of gE in an immunocompetent host. CONCLUSIONS: This report describes a mutant VZV responsible for an aggressive clinical course in an immunocompetent host. Linking these severe clinical presentations of VZV infection to virus mutations might provide insights into the underlying pathogenic mechanisms. 相似文献
23.
Maria Rosaria Gualano Alessio Corradi Gianluca Voglino Dario Catozzi Elena Olivero Michele Corezzi Fabrizio Bert Roberta Siliquini 《Vaccine》2021,39(6):901-914
Influenza is a disease responsible for thousands of deaths every year. Although healthcare workers (HCWs) represent a way of contagion for patients, vaccination coverage among them is low. Mandatory vaccination has been proposed, but controversies remain. This systematic review and meta-analysis aimed to assess the acceptance of mandatory vaccination by HCWs, and to investigate associated characteristics. MEDLINE, Scopus, Embase, PsycInfo, CINAHL and Web of Science were used to search for studies assessing the topic. PRISMA statements were followed. Of the 13,457 univocal records found, 52 studies were included in the systematic review and 40 in the meta-analysis. The pooled proportion of HCWs accepting the policy was of 61% (95% CI: 53%- 68%) but with great heterogeneity between continents (from 54% in Europe to 69% in Asia) and in different professionals (from 40% in nurses to 80% in students). Vaccinated HCWs agreed more frequently with mandatory vaccination than non-vaccinated ones. More studies that consider mandatory vaccination acceptance as the main outcome are needed, but the results of this study confirm that in some settings the majority of HCWs favour mandatory vaccination. This, combined with effects that a flu epidemic could have if overlapped to pandemics with similar symptoms, requires renewed considerations on mandatory vaccination. 相似文献
24.
Vianello F Olszak IT Poznansky MC 《Journal of molecular medicine (Berlin, Germany)》2005,83(10):752-763
Chemotaxis or active movement of leukocytes toward a stimulus has been shown to occur in response to chemokinetic agents including members of the recently identified superfamily of proteins called chemokines. Leukocyte chemotaxis is thought to play a central role in a wide range of physiological and pathological processes including the homing of immune cells to lymph nodes and the accumulation of these cells at sites of tissue injury and pathogen or antigen challenge. We have recently identified a novel biological mechanism, which we term fugetaxis (fugere, to flee from; taxis, movement) or chemorepulsion, which describes the active movement of leukocytes away from chemokinetic agents including the chemokine, stromal cell derived factor-1, and the HIV-1 envelope protein, gp120. In this article, we review the evidence that supports the observation that leukocyte fugetaxis occurs in vitro and in vivo and suggestions that this novel mechanism can be exploited to modulate the immune response. We propose that leukocyte fugetaxis plays a critical role in both physiological and pathological processes in which leukocytes are either excluded or actively repelled from specific sites in vivo including thymic emigration, the establishment of immune privileged sites and immune evasion by viruses and cancer. We believe that current data support the thesis that a greater understanding of leukocyte fugetaxis will lead to the development of novel therapeutic approaches for a wide range of human diseases. 相似文献
25.
Zoledronic acid-related angiogenesis modifications and survival in advanced breast cancer patients. 总被引:5,自引:0,他引:5
Bruno Vincenzi Daniele Santini Giordano Dicuonzo Fabrizio Battistoni Michele Gavasci Annalisa La Cesa Claudia Grilli Vladimir Virzì Simona Gasparro Laura Rocci Giuseppe Tonini 《Journal of interferon & cytokine research》2005,25(3):144-151
The proven antiangiogenic activity of zoledronic acid, a third-generation bisphosphonate widely used in bone metastatic cancer patients, led us to investigate if the vascular endothelial growth factor (VEGF)-related zoledronic acid modifications are correlated with survival advantages in advanced breast cancer patients. Forty-two consecutive breast cancer patients with scintigraphic and radiographic evidence of bone metastases were treated with a single infusion of 4 mg zoledronic acid before anticancer chemotherapy. The patients were prospectively evaluated for circulating levels of VEGF and interferon-gamma (IFN-gamma) just before and at 1, 2, 7, and 21 days after zoledronic acid infusion. Afterward, clinical outcome was prospectively monitored. The basal serum VEGF median levels were significantly decreased at each time point, but the major reduction was recorded 21 days after the infusion. In particular, 25 patients of 42 (59.5%) experienced a reduction of at least 25% in the VEGF circulating levels. In contrast, no statistically significant modifications of the IFN-gamma serum levels were recorded. We stratified patients on the basis of this VEGF reduction 21 days after the infusion. No differences in patient features were recorded between those with or without the VEGF reduction. The analysis of survival showed that patients with a reduction in the VEGF circulating levels had a longer time to first skeletal-related event (p = 0.0002), time to bone progression disease (p = 0.0024), and time to performance status worsening (p = 0.0352) than those without the VEGF reduction. No statistically significant differences were recorded in terms of overall survival and time to visceral progression. This study confirms that zoledronic acid could have an in vivo antiangiogenic property and that the VEGF modifications may represent a surrogate marker able to predict time to first skeletal-related event, time to bone progression disease, and time to worsening of performance status. 相似文献
26.
Valentina Mazzotta Alessandro Cozzi Lepri Francesca Colavita Silvia Rosati Eleonora Lalle Claudia Cimaglia Jessica Paulicelli Ilaria Mastrorosa Serena Vita Lavinia Fabeni Alessandra Vergori Gaetano Maffongelli Fabrizio Carletti Simone Lanini Emanuela Caraffa Eugenia Milozzi Raffaella Libertone Pierluca Piselli Enrico Girardi AnnaRosa Garbuglia Francesco Vaia Fabrizio Maggi Emanuele Nicastri Andrea Antinori INMI COVID- Outpatient Treatment Study Group 《Journal of medical virology》2023,95(1):e28186
27.
Crossed aphasia. An update 总被引:2,自引:0,他引:2
Luciano Mastronardi Luigi Ferrante Alberto Maleci Fabrizio Puzzilli Pierpaolo Lunardi Giuseppe Schettini 《Neurosurgical review》1994,17(4):299-304
The aim of this article is to present an update of a rare but interesting problem: crossed aphasia. This term indicates the presence of aphasia after unilateral cerebral lesion of the hemisphere ipsilateral to the patient's dominant hand. We report two cases, review the most relevant literature, and analyze clinical, neuroanatomical, and neurophysiological aspects, taking in consideration the various interpretations proposed to explain this unusual language disorder. 相似文献
28.
Troisi E Silvestrini M Matteis M Monaldo BC Vernieri F Caltagirone C 《Journal of neurology》1999,246(12):1172-1176
This study assessed the use of transcranial Doppler ultrasound in detecting selective changes in cerebral blood flow velocity
during emotional processes. The role of the respective hemispheres in emotional processing is controversial. Cerebral control
of emotional processing has previously been investigated by analysis of patients with unilateral brain damage, experiments
with selective stimulation of only one hemisphere, and more recently by imaging techniques measuring local cerebral blood
flow. We investigated mean flow velocity continuously and simultaneously in both the right and left middle cerebral arteries
(MCAs) in 16 healthy right-handed young subjects at rest and during the performance of three tasks: task 1: 15 slides with
nonemotional content; task 2: 15 slides with negative emotional content; task 3: 15 slides with nonemotional content with
different content from that in task 1. The three tasks produced significantly different effects on the right and left hemispheres.
During the two nonemotional tasks the increase in mean flow velocity over basal values was similar in the two MCAs (task 1:
left MCA = 3.27 ± 1.9%; right MCA = 3.63 ± 2.1%; task 3: left MCA = 2.42 ± 0.7%; right MCA = 2.56 ± 1.3%); the negative emotional
task was accompanied by a significantly higher increase in the right (11.31 ± 1.6%) than in the left MCA (4.72 ± 3.7%; analysis
of variance two-way interaction: side of recording x task, F = 43.6, P < 0.001). These results show the possibility of obtaining specific functional information from bilateral transcranial Doppler
ultrasound and suggest the involvement of the right hemisphere in emotional processing.
Received: 4 March 1999 Received in revised form: 29 June 1999 Accepted: 5 August 1999 相似文献
29.
Fabrizio Tagliavini Giorgio Giaccone Orso Bugiani Blas Frangione 《Acta neuropathologica》1993,85(3):267-271
Summary Here ditary cerebral hemorrhage with amyloidosis Dutch type (HCHWA-D) is characterized clinically by recurrent strokes and pathologically by deposition of amyloid (A) in cerebral vessel walls and, to a lesser extent, in the neuropil. Distinct from Alzheimer's disease, amyloid formation in HCHWA-D is not associated with neurofibrillary changes. Since a central issue in the pathophysiology of Alzheimer's disease and related conditions is the role of A in the neurodegencrative process, we investigated HCHWA-D brains for the presence of neuritic abnormalities using antibodies to ubiquitin and to phosphorylated neurofilaments. The study showed that amyloid deposits in the vessel walls and in the neuropil were surrounded by abnormal ubiquitinated neurites, suggesting that A deposition induces neuritic changes.Supported by the Italian Ministry of Health. Department of Social Services, and by N.I.H. Grants AG05891 and AG08721 (to B.F.) 相似文献
30.
Luigi Ferrante Luciano Mastronardi Pierpaolo Lunardi Fabrizio Puzzilli Aldo Fortuna 《European spine journal》1992,1(1):25-28
Summary We report 48 patients operated on for lumbar disc herniation in the second decade of life (aged 13–20 years) in our Neurosurgical Division. To analyze the clinical and diagnostic features and surgical outcome of the disease in teenagers and to point out any differences from adults, we made a detailed study of over 900 juvenile cases and compared them with 11000 adult cases reported in the literature. Low-back pain proved to be less frequent among youngsters both as a first symptom and at diagnosis, while sensorimotor deficits have the same frequency in the two age groups. Herniation occurs more often at L4–L5 and is more frequently median among teenagers. The long-term surgical results in children and adolescents are better than in adults. 相似文献