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排序方式: 共有756条查询结果,搜索用时 15 毫秒
41.
Vargas-Gandica Jair Winter Daniel Schnippe Rainer Rodriguez-Morales Andrea G. Mondragon Johana Escalera-Antezana Juan Pablo Trelles-Thorne María del Pilar Bonilla-Aldana D. Katterine Rodriguez-Morales Alfonso J. Paniz-Mondolfi Alberto 《Journal of neurovirology》2020,26(5):785-789
Journal of NeuroVirology - Over the course of the pandemic due to the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), multiple new clinical manifestations, as the consequence of the... 相似文献
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43.
MC Chau SF Leung KM Kam KY Cheung WH Kwan KH Yu KW Chiu TC Chan 《Journal of Medical Imaging and Radiation Oncology》2007,51(5):480-484
To assess the dosimetric effect of using interpolated contours in planning intensity‐modulated radiation therapy (IMRT) for advanced T‐stage nasopharyngeal carcinoma. The present study focused on T3–T4 tumours where the proximity of targets to neurological organs poses a stringent test on the feasibility of such an approach. Contours of targets and organs were delineated on CT images of 2.5‐mm interval and a reference IMRT plan was generated. An investigative (INV) IMRT plan was then generated with the same planning protocol, but based on interpolated contours that replaced deleted contours on alternate slices. The reference and INV plans were compared. Regarding target coverage, all targets in the INV plans met the acceptance criteria except for the PTV in one case. Regarding organs, the mean dose to 1% volume of the brainstem and spinal cord in the INV plans were kept below their dose limits. No significant differences in the mean doses to others organs were found. Satisfactory target coverage and protection of critical organs to a degree similar to full‐scale contouring could be achieved with use of interpolated contours. The saving in manpower time for contouring is expected to significantly improve the throughput of the IMRT planning process. 相似文献
44.
Carrie E Bearden Paul M Thompson Rebecca A Dutton Benício N Frey Marco A M Peluso Mark Nicoletti Nicole Dierschke Kiralee M Hayashi Andrea D Klunder David C Glahn Paolo Brambilla Roberto B Sassi Alan G Mallinger Jair C Soares 《Neuropsychopharmacology》2008,33(6):1229-1238
Declarative memory impairments are common in patients with bipolar illness, suggesting underlying hippocampal pathology. However, hippocampal volume deficits are rarely observed in bipolar disorder. Here we used surface-based anatomic mapping to examine hippocampal anatomy in bipolar patients treated with lithium relative to matched control subjects and unmedicated patients with bipolar disorder. High-resolution brain magnetic resonance images were acquired from 33 patients with bipolar disorder (21 treated with lithium and 12 unmedicated), and 62 demographically matched healthy control subjects. Three-dimensional parametric mesh models were created from manual tracings of the hippocampal formation. Total hippocampal volume was significantly larger in lithium-treated bipolar patients compared with healthy controls (by 10.3%; p=0.001) and unmedicated bipolar patients (by 13.9%; p=0.003). Statistical mapping results, confirmed by permutation testing, revealed localized deficits in the right hippocampus, in regions corresponding primarily to cornu ammonis 1 subfields, in unmedicated bipolar patients, as compared to both normal controls (p=0.01), and in lithium-treated bipolar patients (p=0.03). These findings demonstrate the sensitivity of these anatomic mapping methods for detecting subtle alterations in hippocampal structure in bipolar disorder. The observed reduction in subregions of the hippocampus in unmedicated bipolar patients suggests a possible neural correlate for memory deficits frequently reported in this illness. Moreover, increased hippocampal volume in lithium-treated bipolar patients may reflect postulated neurotrophic effects of this agent, a possibility warranting further study in longitudinal investigations. 相似文献
45.
Lacerda AL Nicoletti MA Brambilla P Sassi RB Mallinger AG Frank E Kupfer DJ Keshavan MS Soares JC 《Psychiatry research》2003,124(3):129-140
The basal ganglia form a part of the brain neuroanatomic circuits that may be involved in mood regulation. Decreases in basal ganglia volumes have been previously reported in major depressive disorder patients in comparison to healthy controls. In this study, we measured caudate, putamen, and globus pallidus volumes in 25 patients with major depressive disorder (4 M; age+/-S.D.=41+/-11 years) and 48 healthy controls (29 M; age+/-S.D.=35+/-10 years), using high-resolution magnetic resonance imaging (MRI), in an attempt to replicate prior findings. Unlike most previous studies, we did not find significant differences between patient and control groups in basal ganglia volumetric measures. Nonetheless, there was a significant interaction between diagnosis and cerebral hemisphere, with MDD patients showing decreased asymmetry in globus pallidus volumes in comparison with healthy controls. Furthermore, in the patient group, left putamen volumes correlated inversely with length of illness, and left globus pallidus volume correlated directly with number of prior depressive episodes. These findings suggest that abnormalities in lateralization and possibly neurodegenerative changes in basal ganglia structures participate in the pathophysiology of major depressive disorder. 相似文献
46.
Management of odontoid fractures using anterior screw fixation: analysis of 15 cases 总被引:8,自引:0,他引:8
Dantas FL Prandini MN Caires AC Fonseca GA Raso JL 《Arquivos de neuro-psiquiatria》2002,60(3-B):823-829
A retrospective analysis of the results of 15 patients with odontoid fractures type II P and II N, according to Roy-Camille's classification is presented. They were operated on by an anterior approach and direct fixation of the odontoid process through a screw. There were 13 men and 2 women, the age ranging from 14 to 74 years. The follow up period was from 6 to 36 months (mean 20 months). There was only one complication related to the surgical technique: one screw was misplaced and it was necessary another surgery to replace it. There were no deaths in this series. There were no screw breakdown and the fusion rate was 94%. We propose, based on this study, that the classification of Roy-Camille for odontoid fractures should be always used, since it proposes one surgical approach for each type of fracture. The results of this series show that this technique is useful and has advantages over another modalities of treatment. The correct diagnosis of the type of fracture and an appropriate selection of patients are the main elements to achieve good results. 相似文献
47.
MJ Veness F Foroudi V Gebski I Timms Y Sathiyaseelan B Cakir KW Tiver 《Journal of Medical Imaging and Radiation Oncology》2006,50(5):468-474
Radiation‐induced mucositis is an acute reaction of the mucosa of patients undergoing head and neck radiotherapy. It can have debilitating and dose‐limiting consequences. There is no consensus on an accepted intervention that significantly reduces its severity. Misoprostol is a synthetic prostaglandin E1 analogue, with properties of a mucosal cytoprotectant. We designed a randomized, double‐blind, placebo‐controlled trial of misoprostol in patients with head and neck cancer. The aim of this study was to determine if topical misoprostol was effective in reducing the severity of radiation‐induced mucositis in patients receiving radical dose radiotherapy. The effect of this intervention on a patient’s general well‐being was also investigated. The primary end‐point of the study was the incidence of Radiation Therapy Oncology Group grade 3 mucositis. Between 1999 and 2002, 83 patients were recruited into the study at Westmead and Nepean Hospitals, Sydney. Forty‐two patients were randomized to receive misoprostol and 41 to receive a placebo. Most patients received radiotherapy in the adjuvant setting (52 of the 83) and had either an oral cavity (42 of the 83) or an oropharyngeal (16 of the 83) cancer. We could not identify any significant difference in the incidence of severe mucositis based on whether patients were allocated to receive misoprostol or placebo. There was no significant difference in the mean area under the mucositis curve (13.2 vs 16.6; P = 0.1). Patients allocated to misoprostol did report slightly increased soreness (7.6 vs 6.9; P = 0.04) and a greater use of analgesics. However, this difference did not translate into a worse feeling of general well‐being as measured by a simple visual analogue scale (5.8 vs 5.2; P = 0.3). In conclusion, we were unable to identify a reduction in radiation‐induced mucositis in patients receiving misoprostol. There is a paucity of high‐level evidence on potentially useful interventions and a continued need for new and innovative research, incorporating quality‐of‐life measurements, in patients experiencing radiation‐induced mucositis. 相似文献
48.
49.
Glahn DC Bearden CE Caetano S Fonseca M Najt P Hunter K Pliszka SR Olvera RL Soares JC 《Bipolar disorders》2005,7(6):546-554
OBJECTIVES: Impaired verbal declarative memory has been proposed as a trait marker for adult bipolar disorder. However, similar impairments in juvenile-onset bipolar disorder have not been yet documented. Here, we assessed declarative memory in a large sample of clinically well-characterized children with bipolar disorder. METHODS: Forty-one children and adolescents with bipolar disorder [21 bipolar I disorder (BP-I), 10 bipolar II disorder (BP-II), and 10 bipolar disorder, not otherwise specified (BP-NOS)] and 17 demographically matched healthy participants completed a standardized learning and memory test. RESULTS: BP-I children recalled and recognized significantly fewer words than healthy subjects, whereas children with BP-II and BP-NOS did not differ from controls. However, individuals with BP-NOS made more perseverative errors and intrusions than the other groups. Severity of mood symptomatology was not associated with memory performance in any bipolar subtype. CONCLUSIONS: Findings suggest that declarative memory impairments in juvenile BP-I are similar to those seen in the adult form of the illness. These impairments do not appear to be secondary to clinical state; rather, they may reflect trait-related impairments. Distinct performance patterns in BP-I, BP-II, and BP-NOS suggest that the broadly defined phenotype is significantly heterogeneous, and may not be informative for pathogenetic investigations of bipolar disorder. 相似文献
50.
Sassi RB Stanley JA Axelson D Brambilla P Nicoletti MA Keshavan MS Ramos RT Ryan N Birmaher B Soares JC 《The American journal of psychiatry》2005,162(11):2109-2115
OBJECTIVE: Converging evidence implicates prefrontal circuits in the pathophysiology of bipolar disorder. Proton spectroscopy studies performed in adult bipolar patients assessing prefrontal regions have suggested decreased levels of N-acetylaspartate (NAA), a putative marker of neuronal integrity. In order to examine whether such abnormalities would also be found in younger patients, a 1H spectroscopy study was conducted that focused on the dorsolateral prefrontal cortex of children and adolescents with bipolar disorder. METHOD: The authors examined the levels of NAA, creatine plus phosphocreatine, and choline-containing molecules in the left dorsolateral prefrontal cortex of 14 bipolar disorder patients (mean age=15.5 years, SD=3, eight female) and 18 healthy comparison subjects (mean age=17.3, SD=3.7, seven female) using short echo time, single-voxel in vivo 1H spectroscopy. Absolute metabolite levels were determined using the water signal as an internal reference. RESULTS: Bipolar patients presented significantly lower NAA levels and a significant inverse correlation between choline-containing molecules and number of previous affective episodes. No differences were found for other metabolites. CONCLUSIONS: These findings suggest that young bipolar patients have decreased NAA levels in the dorsolateral prefrontal cortex, similar to what was previously reported in adult patients. Such changes may reflect an underdevelopment of dendritic arborizations and synaptic connections. These neuronal abnormalities in the dorsolateral prefrontal cortex of bipolar disorder youth are unlikely to represent long-term degenerative processes, at least in the subgroup of patients where the illness had relatively early onset. 相似文献