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913.
In the last two decades functional magnetic resonance imaging (fMRI) has dominated research in neuroscience. However, only recently has it taken the first steps in translation to the clinical field. In this paper we describe the advantages of fMRI and DTI and the possible benefits of implementing these methods in clinical practice. We review the current clinical usages of fMRI and DTI and discuss the challenges and difficulties of translating these methods to clinical use. The most common application today is in neurosurgery. fMRI and DTI are done preoperatively for brain tumor patients who are having tumors removed and for epilepsy patients who are candidates for temporal resection. Imaging results supply the neurosurgeon with essential information regarding possible functional damage and thereby aid both in planning and performing surgery. Scientific research suggests more promising potential implementations of fMRI and DTI in improving diagnosis and rehabilitation. These advanced imaging methods can be used for pre-symptomatic diagnosis, as a differentiating biomarker in the absence of anatomical measurements, and for identification of mental response in the absence of motor-sensory abilities. These methods can aid and direct rehabilitation by predicting the success of possible interventions and rehabilitation options and by supplying a measure for biofeedback. This review opens a window to the state of the art neuroimaging methods being implemented these days into the clinical practice and provides a glance to the future clinical possibilities of fMRI and DTI. 相似文献
914.
Detection of precursor Th cells in mesenteric lymph nodes after oral immunization with protein antigen and cholera toxin 总被引:2,自引:0,他引:2
We have characterized the earliest antigen-specific Th cells in murine
mesenteric lymph nodes (MLN), following oral immunization with the hen egg
lysozyme (HEL) as antigen and cholera toxin (CT) as adjuvant. We did this
by analyzing in vitro proliferation and cytokine production in response to
HEL by the MLN T cells. MLN cells taken 5 days after a single oral
immunization with HEL and CT provided the earliest source of proliferating
HEL-specific T cells. This proliferation was completely inhibited by
anti-IL-2, but not inhibited by anti-IL-4 antibody. IL-2 protein was
detected in culture supernatants but not IL- 4 using ELISA or bioassays.
IL-4 mRNA was not found in responding cells using RT-PCR. Some of the day 5
MLN cultures produced IFN-gamma in response to HEL, but isolated T cells
from the same MLN did not. Exogenous IL-4 alone did not stimulate day 5 MLN
T cells, but IL-4 did synergize with HEL to induce a large proliferative
response. The data indicate that the HEL-specific CD4 T cell pool in MLN 5
days after oral immunization is composed of undifferentiated precursor Th
cells. These cells have the potential for IL-2 production and IL-4R
expression upon re-stimulation in vitro.
相似文献
915.
Rozen N Lewinson D Bick T Meretyk S Soudry M 《Critical reviews in eukaryotic gene expression》2007,17(3):197-213
Although most fractures heal in accordance with a highly regulated and well-known multistep process, 5%-10% of fractures result in delayed union or nonunion, causing morbidity, prolonged hospitalization, and economic cost for the individual and society. Ongoing research has improved our understanding of genes and molecules that are expressed during fracture healing. This knowledge has been translated into preclinical/clinical trials. Unfortunately, the success of most promising agents, and therefore most preclinically/clinically tested factors, is controversial and frequently disappointing. Taking advantage of our knowledge concerning the temporal events contributing to fracture healing, and as a result of our studies, we suggest that the application of several factors in sequence will intervene in different, crucial crossroads, accelerate remodeling, and result in an improved outcome. These factors will encompass stimulated recruitment and proliferation of stem cells to enlarge the progenitor pool, facilitate its differentiation into mature chondrocytes and osteoblasts, and stimulate cartilage resorption and its remodeling into bone by endochondral ossification--a process in which blood vessels, metalloproteinases, and osteoclasts work in concert to remodel immature bone into mature bone. The aim of this article is to highlight events that contribute to and drive the dynamic healing process in order to help clinicians to find successful, novel treatment protocols. 相似文献
916.
CC Bonifácio§ CJ Kleverlaan† DP Raggio‡ A Werner† RCR de Carvalho WE van Amerongen§ 《Australian dental journal》2009,54(3):233-237
Background: This study evaluated mechanical properties of glass ionomer cements (GICs) used for atraumatic restorative treatment. Wear resistance, Knoop hardness (Kh), flexural (Fs ) and compressive strength (Cs ) were evaluated. The GICs used were Riva Self Cure (RVA), Fuji IX (FIX), Hi Dense (HD), Vitro Molar (VM), Maxxion R (MXR) and Ketac Molar Easymix (KME).
Methods: Wear was evaluated after 1, 4, 63 and 365 days. Two-way ANOVA and Tukey post hoc tests (P = 0.05) analysed differences in wear of the GICs and the time effect. Fs , Cs , and Kh were analysed with one-way ANOVA.
Results: The type of cement (p < 0.001) and the time (p < 0.001) had a significant effect on wear. In early-term wear and Kh, KME and FIX presented the best performance. In long-term wear, F s and Cs , KME, FIX and HD had the best performance. Strong explanatory power between Fs and the Kh (r2 = 0.85), Cs and the Kh (r2 = 0.82), long-term wear and Fs of 24 h (r2 = 0.79) were observed.
Conclusions: The data suggested that KME and FIX presented the best in vitro performance. HD showed good results except for early-term wear. 相似文献
Methods: Wear was evaluated after 1, 4, 63 and 365 days. Two-way ANOVA and Tukey post hoc tests (P = 0.05) analysed differences in wear of the GICs and the time effect. F
Results: The type of cement (p < 0.001) and the time (p < 0.001) had a significant effect on wear. In early-term wear and Kh, KME and FIX presented the best performance. In long-term wear, F
Conclusions: The data suggested that KME and FIX presented the best in vitro performance. HD showed good results except for early-term wear. 相似文献
917.
Summary
Teleradiologysystems can differ considerably in their features. The most important differences lie in the mode of image data
acquisition, data transfer, data safety aspects and the possibilities of interaction between seperate teleradiology units.
A selection of commercially available teleradiologysystems is presented and compared.
Eingegangen am 3. Februar 1997 Angenommen am 19.Februar 1997 相似文献
918.
CT of the pulmonary nodule: a cooperative study 总被引:31,自引:0,他引:31
Zerhouni EA; Stitik FP; Siegelman SS; Naidich DP; Sagel SS; Proto AV; Muhm JR; Walsh JW; Martinez CR; Heelan RT 《Radiology》1986,160(2):319-327
To evaluate the role of computed tomography (CT) in the investigation of pulmonary nodules, a special reference phantom that enabled CT densitometric measurements independent of variations between scanners and patients was used in ten institutions. A total of 384 nodules not considered calcified by conventional methods were examined; 118 (31%) proved to be benign, and in 65 of these (55%), unsuspected calcification was demonstrated. In 28 of the 65, definite calcification could be identified on thin-section CT scans by simple inspection of the scans at narrow windows. In the remaining 37, presence of calcification could not be clearly established without comparison with the reference CT number from the calibration phantom. CT was most effective in establishing the benignancy of nodules 3 cm or less in diameter and those with discrete or smooth margins. CT rarely yields a confident diagnosis of benign disease in larger nodules and in those with irregular or spiculated borders. After review of prior spot radiographs, low kilovolt peak spot radiographs, and conventional tomograms, the authors conclude that thin-section CT aided by a reference phantom in equivocal cases should be an integral part of the diagnostic approach to the pulmonary nodule. 相似文献