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31.
Inhibitory motor control in children with attention-deficit/hyperactivity disorder: event-related potentials in the stop-signal paradigm. 总被引:4,自引:0,他引:4
Aneta Dimoska Stuart J Johnstone Robert J Barry Adam R Clarke 《Neuropsychopharmacology》2003,54(12):1345-1354
BACKGROUND: The aim of the study was to investigate the inhibitory control of an ongoing motor response and to identify underlying neural deficiencies, manifested in event-related potentials, that cause poorer inhibitory performance in children with attention-deficit/hyperactivity disorder. METHODS: A stop-signal paradigm with a primary visual task and auditory stop signal was used to compare performance in 13 children with attention-deficit/hyperactivity disorder and 13 control children, while event-related potentials were recorded simultaneously. RESULTS: Children with attention-deficit/hyperactivity disorder showed poorer inhibitory performance through a slower inhibitory process. Inhibitory processing of auditory stop signals was marked by a frontal N2 component that was reduced in the attention-deficit/hyperactivity disorder group relative to controls. A central positive component (P3) was associated with the success of inhibiting a response, but there were no group differences in its amplitude or latency. CONCLUSIONS: Findings support the hypothesis of deficient inhibitory control in children with attention-deficit/hyperactivity disorder. Slower inhibitory processing appears to be due to a specific neural deficiency that manifests in the processing of the stop signal as attenuated negativity in the N2 latency range. 相似文献
32.
Eberhard Henze Gerhard Graf Malte Clausen Bertram Rail Rolf Weller Dieter Derichs Joachim Kreidler Peter Heidenreich F. Sitzmann Willi Ernst Adam 《European journal of nuclear medicine and molecular imaging》1990,16(2):97-101
The exact regional correlation of findings of facial bone scans, planar or SPECT, to dental orthopan X-ray films (OPT) is difficult because of the very different projection techniques. To improve correlative imaging in this regard a projection algorithm was developed that uses SPECT data of the skull for reconstructing an orthopan tomoscintigraphic projection. Fourteen conventional SPECT slices of the upper and lower jaws were obtained during bone scanning. All mandibular slices were superimposed resulting in a horseshoe shaped structure, which was marked by an ROI which was divided into segments. All 14 SPECT slices were then masked by this segmental ROI, thereby marking the teeth-carrying bone in all slices. The information from this horseshoe like ROI is then transformed into lines. Line by line arrangement results in an orthopan projection, the orthopan tomoscintigram. This new display allows 1:1 true scale superimposition with the X-ray OPT and markedly facilitates correlative imaging. 相似文献
33.
Priv.-Doz. Dr. Arndt Klocke Bärbel Kahl-Nieke Gerhard Adam Jörn Kemper 《Journal of orofacial orthopedics》2006,67(6):424-429
BACKGROUND: In a previous investigation we reported on magnetic forces in the static magnetic field of a 1.5 Tesla MRI system. The aim of the present investigation was to assess forces on orthodontic wires in a high field strength MRI system at 3 Tesla. MATERIALS AND METHODS: Thirty-two different orthodontic wires (21 archwires, eight ligature wires and three retainer wires) were investigated in a 3 Tesla high field strength MRI system (Intera, Philips Medical Systems, Best, The Netherlands). Translational forces were measured by the deflection angle test (ASTM F2052-02), and rotational forces assessed on a 5-point qualitative scale. RESULTS AND CONCLUSION: Translational forces ranged between 43.5 mN and 136.1 mN for retainer wires and between 0.6 mN (Noninium) and 208.4 mN (Orthos Stainless Steel) for steel archwires. Translational forces were up to 53.8 times as high as gravitational forces for retainer wires and up to 54.5 times as high for steel archwires, associated with marked rotational forces for the most part. Archwires manufactured from nickel-titanium, titanium-molybdenum and cobalt-chromium and different ligature wires showed no or negligible forces in the magnetic field. Carefully ligated wires should not present a risk due to translational and rotational forces in the high field MRI system at 3 Tesla. 相似文献
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Björn-Christian Link Emre F. Yekebas Dean Bogoevski Asad Kutup Gerhard Adam Jakob R. Izbicki Gerrit Krupski 《Journal of gastrointestinal surgery》2007,11(2):166-170
Symptomatic biliary leakage following major upper abdominal surgery is a severe complication resulting in increased morbidity
and mortality. Treatment options usually include either endoscopic intervention or surgical revision. These options may be
burdened by a high perioperative risk for the patient (e.g., patients with severe disease) or simply may not be possible (e.g.,
nonpreserved gastroduodenal passage). In the past, percutaneous transhepatic cholangiodrainage did only seem to be a viable
option for patients with dilated bile ducts. Here, we present our experience in a consecutive series of patients with symptomatic
biliary leakage following major upper abdominal surgery and without dilation of the biliary system that underwent percutaneous
transhepatic cholangiodrainage. Percutaneous transhepatic cholangiodrainage was feasible in 15 of 18 patients (83.3%). The
procedure was technically not possible in three patients (16.7%). In 10 of the 15 patients (66.6%) with feasible percutaneous
transhepatic cholangiodrainage, biliary leakage was definitely controlled without the need for surgical revision. Depending
on the experience with the interventional procedure, percutaneous transhepatic cholangiodrainage should be considered as an
alternative for treatment of symptomatic biliary leakage instead of immediate reoperation.
Presented at the Digestive Disease Week 2005 (DDW), Chicago, IL, May 14–19, 2005 (poster presentation). 相似文献
37.
Kristin Fraser Adam Peets Ian Walker Janet Tworek Michael Paget Bruce Wright & Kevin McLaughlin 《Medical education》2009,43(8):784-789
Context Prior research has demonstrated that residents have poor clinical skills in cardiology and respirology. It is not clear how these skills can be improved because the number of patients with suitable clinical findings whose cooperation might help residents to better develop these clinical skills is limited.
Objectives Our objective was to evaluate the effect of training on a cardiorespiratory simulator (CRS) on skills acquisition, retention and transfer.
Methods We randomly allocated 146 students to CRS training in either chest pain or dyspnoea and compared each student's performance on the clinical presentation in which he or she had received CRS training with performance on the control presentation.
Results Immediately after training, students were more accurate in identifying abnormal clinical findings on the CRS (70.0% versus 52.2%; d = 7.6, P < 0.0001) and showed improved diagnostic performance (72.1% versus 55.6%; d = 4.3, P = 0.0007) on the training clinical presentation. At the end of the course they were still better at identifying abnormal findings (57.1% versus 51.7%; d = 2.5, P = 0.004) and diagnosing correctly (50.0% versus 38.1%; d = 3.0, P = 0.002) on problems included in the training clinical presentation. However, they showed no difference between training and control presentations in diagnostic performance when required to transfer their skills between problems (45.9% versus 43.8%; P = 0.5) or in performance on multiple-choice questions (64.1% versus 63.6%; P = 0.8).
Conclusions Students can acquire and retain clinical skills with CRS training, but demonstrate limited ability to transfer these to other problems. Further studies are needed to explore ways of improving learning and transfer with CRS training. 相似文献
Objectives Our objective was to evaluate the effect of training on a cardiorespiratory simulator (CRS) on skills acquisition, retention and transfer.
Methods We randomly allocated 146 students to CRS training in either chest pain or dyspnoea and compared each student's performance on the clinical presentation in which he or she had received CRS training with performance on the control presentation.
Results Immediately after training, students were more accurate in identifying abnormal clinical findings on the CRS (70.0% versus 52.2%; d = 7.6, P < 0.0001) and showed improved diagnostic performance (72.1% versus 55.6%; d = 4.3, P = 0.0007) on the training clinical presentation. At the end of the course they were still better at identifying abnormal findings (57.1% versus 51.7%; d = 2.5, P = 0.004) and diagnosing correctly (50.0% versus 38.1%; d = 3.0, P = 0.002) on problems included in the training clinical presentation. However, they showed no difference between training and control presentations in diagnostic performance when required to transfer their skills between problems (45.9% versus 43.8%; P = 0.5) or in performance on multiple-choice questions (64.1% versus 63.6%; P = 0.8).
Conclusions Students can acquire and retain clinical skills with CRS training, but demonstrate limited ability to transfer these to other problems. Further studies are needed to explore ways of improving learning and transfer with CRS training. 相似文献
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Botulinum Toxin A in the Treatment of Chromhidrosis 总被引:1,自引:0,他引:1
Wu Jessie M. Mamelak Adam J. MD † Nussbaum Rachel MD † McElgunn Patrick S. J. MD MBA † 《Dermatologic surgery》2005,31(8):963-965
Background. Chromhidrosis is an uncommon disorder characterized by secretion of colored sweat by apocrine glands, typically localized to the face or axilla. The current treatments available for chromhidrosis are time consuming and frequently ineffective.
Objective. Our purpose is to demonstrate a novel approach to the treatment of apocrine chromhidrosis.
Methods. We report a case of apocrine chromhidrosis successfully treated with botulinum toxin A (BTX-A; Botox).
Results. BTX-A therapy successfully controlled facial chromhidrosis, and the effects were visible at 19 weeks post-treatment. The therapeutic benefits may be attributed to its inhibitory effects on cholinergic stimulation, adrenergic stimulation, and substance P release, although further studies are necessary to elucidate the precise mechanism of action.
Conclusion. This report demonstrates a new therapeutic approach to patients suffering from chromhidrosis. 相似文献
Objective. Our purpose is to demonstrate a novel approach to the treatment of apocrine chromhidrosis.
Methods. We report a case of apocrine chromhidrosis successfully treated with botulinum toxin A (BTX-A; Botox).
Results. BTX-A therapy successfully controlled facial chromhidrosis, and the effects were visible at 19 weeks post-treatment. The therapeutic benefits may be attributed to its inhibitory effects on cholinergic stimulation, adrenergic stimulation, and substance P release, although further studies are necessary to elucidate the precise mechanism of action.
Conclusion. This report demonstrates a new therapeutic approach to patients suffering from chromhidrosis. 相似文献