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111.
Felix Matthews Valentin Neuhaus Daniel Schmucki Ronald Schwyn Thomas Gross Pietro Regazzoni Otmar Trentz Peter Messmer 《European Journal of Trauma》2005,31(6):568-574
Abstract During treatment of femoral shaft fractures, not only the actual fracture reduction but also the retention of the achieved
reduction is essential. Substantial forces may apply to the bone fragments, due to multidirectional muscular contraction.
Furthermore, forces from manipulation of one bone fragment may be transferred over the soft tissues onto the other fragments,
thus hindering accurate fracture reduction. Once a sufficient reduction has been achieved, this position must be retained
whilst definitive internal fixation is performed. Conventional methods comprise mounting patients on a traction table and
applying manual distraction or employing special distraction devices, such as the AO distractor device. These approaches,
however, only insufficiently stabilize both main fragments. For example, on the traction table the proximal femoral fragment
can pivot around the hip joint thus complicating precise reduction. A novel pneumatic stabilization device to assist surgeons
during operative procedures is described. This passive holding device “Passhold” connects to one main fragment through a minimally
invasive bone interface and statically locks the fragment’s position. Thereafter, only the other main fragment is manipulated
to achieve reduction. Mutual interference of the reciprocal fragment positions, due to soft-tissue force transfer during manipulation,
is avoided. The authors examined the stability of the novel retention device on a test rig and proved its functionality under
sterile settings using cadaver tests. It is concluded that this device largely facilitates the operative procedure in femoral
shaft fractures, is sufficiently stable and ergonomically suitable for intraoperative deployment. 相似文献
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BACKGROUND: Aripiprazole (Abilify) is an atypical antipsychotic drug primarily characterized by partial agonist activity at dopamine (DA) D2 receptors and low side effects. Based on pharmacologic properties that include a stabilization of mesocorticolimbic DA activity, a pathway implicated in addiction, aripiprazole was tested for its ability to prevent relapse to cocaine seeking in rats. METHODS: We assessed the dose-dependent effects of aripiprazole on conditioned cue-induced and cocaine-primed reinstatement of drug-seeking behavior following chronic intravenous cocaine self-administration in an animal model of relapse. RESULTS: Aripiprazole potently and dose-dependently attenuated responding on the previously cocaine-paired lever during both reinstatement conditions, with slightly greater efficacy at reducing conditioned-cued reinstatement. Aripiprazole was effective at doses that failed to alter cocaine self-administration, food self-administration, reinstatement of food-seeking behavior, or basal locomotor activity, suggesting selective effects of aripiprazole on motivated drug-seeking behavior. CONCLUSIONS: These results in a relapse model show that aripiprazole can block cocaine seeking without affecting other behaviors. The D2 partial agonist properties of aripiprazole likely account for the blockade of reinstatement of cocaine-seeking behavior. Given its established efficacy and tolerability as a treatment for psychosis, aripiprazole may be an excellent therapeutic choice for reducing craving and preventing relapse in people with cocaine dependency. 相似文献
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Verbal Working Memory and Atherosclerosis in Patients with Cardiovascular Disease: An fMRI study 总被引:1,自引:0,他引:1
Andreana P. Haley PhD Lawrence H. Sweet PhD John Gunstad PhD Daniel E. Forman MD Athena Poppas MD Robert H. Paul PhD David F. Tate PhD Ronald A. Cohen PhD 《Journal of neuroimaging》2007,17(3):227-233
BACKGROUND AND PURPOSE: Intimal-medial thickening (IMT) of the carotid wall is an accepted peripheral marker of atherosclerosis. It is associated with increased risk for myocardial infarction and stroke, and lower attention-executive-psychomotor functioning. The purpose of this study was to examine the relationship between IMT and brain activity during a verbal working memory (VWM) task in patients with cardiovascular disease (CVD). METHODS: Thirteen CVD patients underwent functional magnetic resonance imaging (fMRI) during a 2-Back VWM task, and B-mode ultrasound of the carotid arteries. IMT was calculated using an automated algorithm based on a validated edge-detection technique. The relationship between IMT and 2-Back-related brain activity was modeled using partial correlations controlling for age and small vessel disease as measured by white matter signal hyperintensities on MRI (WMH). RESULTS: Higher IMT was associated with lower 2-Back-related signal intensity and in the right middle frontal gyrus, independent of age and WMH. CONCLUSIONS: IMT may be one mechanism contributing to brain dysfunction in CVD. The blood oxygenation level-dependent (BOLD) contrast appears to be highly sensitive to peripheral vascular health as measured by IMT. Future studies should examine the sensitivity and specificity of the BOLD response for predicting cognitive decline in CVD. 相似文献
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The development and introduction of anti-oxytocic tocolytics 总被引:1,自引:0,他引:1
Ronald F. Lamont 《BJOG : an international journal of obstetrics and gynaecology》2003,110(S20):108-112
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