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Functional magnetic resonance imaging (fMRI) is used to distinguish areas of the brain responsible for different tasks and functions. It is possible, for example, by using fMRI images, to identify particular regions in the brain which can be considered as "functional organs at risk" (fOARs), i.e., regions which would cause significant patient morbidity if compromised. The aim of this study is to propose and validate a method to exploit functional information for the identification of fOARs in CyberKnife (Accuray, Inc., Sunnyvale, CA) radiosurgery treatment planning; in particular, given the high spatial accuracy offered by the CyberKnife system, local nonrigid registration is used to reach accurate image matching. Five patients affected by arteriovenous malformations (AVMs) and scheduled to undergo radiosurgery were scanned prior to treatment using computed tomography (CT), three-dimensional (3D) rotational angiography (3DRA), T2 weighted and blood oxygenation level dependent echo planar imaging MRI. Tasks were chosen on the basis of lesion location by considering those areas which could be potentially close to treatment targets. Functional data were superimposed on 3DRA and CT used for treatment planning. The procedure for the localization of fMRI areas was validated by direct cortical stimulation on 38 AVM and tumor patients undergoing conventional surgery. Treatment plans studied with and without considering fOARs were significantly different, in particular with respect to both maximum dose and dose volume histograms; consideration of the fOARs allowed quality indices of treatment plans to remain almost constant or to improve in four out of five cases compared to plans with no consideration of fOARs. In conclusion, the presented method provides an accurate tool for the integration of functional information into AVM radiosurgery, which might help to minimize undesirable side effects and to make radiosurgery less invasive.  相似文献   
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Emotions and feelings are the bricks of our social life and yet we often forget that they have a significant impact on our physical wellbeing. Indeed, a growing number of studies have shown that both an imbalanced or improved emotional state can significantly influence the way our immune system responds. In this commentary, we have summarized the most recent studies on the effects of different types of emotional states on the immune system and we have also explored the effects of mood modulator approaches on the immune response. We hope this commentary will prompt scientists and clinicians to think about the therapeutic value and potential of emotions and feelings in immune-related diseases. At the same time, we think that this commentary will shed some light on the scientific truth behind the very famous expression “It's in my blood” when we talk about feelings and personality.  相似文献   
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BACKGROUND: Some patients with cryoglobulinemic syndrome (CS) develop frank non-Hodgkin lymphoma (NHL), but the incidence and timing of this event are still poorly defined. METHODS: A retrospective multicenter study was performed of hepatitis C virus-positive patients with CS observed in 11 Italian centers belonging to the Italian Group for the Study of Cryoglobulinemia. RESULTS: The inclusion criteria were satisfied by 1,255 patients. During a cumulative follow-up of 8,928 patient-years, 59 cases of NHL were diagnosed, for an estimated rate of 660.8 new cases per 100,000 patient-years with 224.1 new cases of aggressive NHL subtypes per 100,000 patient-years. More than 90% of the patients developing NHLs had type II cryoglobulins. The NHLs were classified as nonaggressive in 31 cases (53%), aggressive in 20 (34%), and mucosa-associated lymphoid tissue lymphomas in 6 (10%); 2 cases were unclassifiable. The median time from the diagnosis of CS to the clinical onset of NHL was 6.26 years (range, 0.81-24 years). The clinical course and response to chemotherapy in the patients with CS who had NHL were similar to those usually described in patients with NHL without CS; the course of the CS only marginally benefited from chemotherapy. CONCLUSIONS: The overall risk of NHL in patients with CS is about 35 times higher than in the general population (12 times higher if nonaggressive lymphomas are excluded). The presence of CS did not significantly affect the treatment of newly diagnosed lymphomas.  相似文献   
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Sport Sciences for Health - The study has compared the effects of a program of guided walking (GW) and of a program of suggested walking (SW) on the blood pressure and on the lifestyle of sedentary...  相似文献   
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The human leukocyte antigen (HLA)-G is a “nonclassical” major histocompatibility complex (MHC) class Ib gene, located at chromosome 6, in the 6p21.3 region.  相似文献   
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In recent years, advances in diagnostics and deep sequencing technologies have led to the identification and characterization of novel viruses in cats as protoparviruses and chaphamaparvoviruses, unveiling the diversity of the feline virome in the respiratory tract. Observational, epidemiological and experimental data are necessary to demonstrate firmly if some viruses are able to cause disease, as this information may be confounded by virus- or host-related factors. Also, in recent years, researchers were able to monitor multiple examples of transmission to felids of viruses with high pathogenic potential, such as the influenza virus strains H5N1, H1N1, H7N2, H5N6 and H3N2, and in the late 2019, the human hypervirulent coronavirus SARS-CoV-2. These findings suggest that the study of viral infections always requires a multi-disciplinary approach inspired by the One Health vision. By reviewing the literature, we provide herewith an update on the emerging viruses identified in cats and their potential association with respiratory disease.  相似文献   
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CD34 is a transmembrane protein that is strongly expressed on hematopoietic stem/progenitor cells (HSCs); despite its importance as a marker of HSCs, its function is still poorly understood, although a role in cell adhesion has been demonstrated. To characterize the function of CD34 antigen on human HSCs, we examined, by both inhibition and overexpression, the role of CD34 in the regulation of HSC lineage differentiation. Our results demonstrate that CD34 silencing enhances HSC granulocyte and megakaryocyte differentiation and reduces erythroid maturation. In agreement with these results, the gene expression profile of these cells reveals the upregulation of genes involved in granulocyte and megakaryocyte differentiation and the downregulation of erythroid genes. Consistently, retroviral-mediated CD34 overexpression leads to a remarkable increase in erythroid progenitors and a dramatic decrease in granulocyte progenitors, as evaluated by clonogenic assay. Together, these data indicate that the CD34 molecule promotes the differentiation of CD34+ hematopoietic progenitors toward the erythroid lineage, which is achieved, at least in part, at the expense of granulocyte and megakaryocyte lineages.  相似文献   
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