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151.
152.
OBJECTIVE: To test whether central motor processing can be impaired in chronic reflex sympathetic dystrophy (RSD). DESIGN: Experimental 2-group analysis. SETTING: Tertiary care center in the Netherlands. PARTICIPANTS: Five patients with stage 3 RSD of the left forearm, free of symptoms and complaints in the right forearm; and 10 healthy control subjects. INTERVENTION: On a digitizer, RSD patients and controls had to draw 3 sequences of graphemes of different complexity with their (unaffected) dominant right hand. The drawing tracks were segmented in time periods between points of velocity minima of the pen tip. MAIN OUTCOME MEASURES: Mean velocity, coefficients of variation of both length and movement time per segment, and mean intersegmental pausing time were calculated for each sequence. RESULTS: A repeated-measures analysis of variance by using the multivariate method yielded a 35% lower mean velocity (F(1,13) = 5.83, P =.031), a 110% larger segment length variability (F(1,13) = 9.72, P =.008) and a 60% larger variability of movement time per segment (F(1,13) = 5.78, P =.032) in RSD patients. No group difference was found for intersegmental pausing time or any interaction effect with the type of task. CONCLUSION: Patients with chronic RSD have a normal ability to preprogram sequential movements of their unaffected hand; but with impaired temporospatial coding and movement execution. We concluded that cortical mechanisms may be involved in motor impairments in patients with chronic RSD.  相似文献   
153.
To study the acute effect of norfenefrine, given orally in aqueous solution, on the urethral closure function, profilometry was performed before and after administration of placebo and increasing doses of norfenefrine in 6 females with genuine stress incontinence. A weak increase in urethral pressure was observed after administration of 90 mg of norfenefrine. No changes in heart rate and blood pressure occurred. The results indicate that the direct sympathomimetic effect of norfenefrine is weak. It is suggested that norfenefrine mainly acts via indirect mechanisms.  相似文献   
154.
First-line therapy for hepatitis C virus (HCV) infection comprises interferon-alpha (IFN-alpha) and ribavirin for 6 or 12 months. Mild complications of therapy are common, but more serious complications are rare. Three patients with chronic HCV infection, acquired through injecting drug use, developed idiopathic facial paralysis (Bell's palsy) during therapy, with spontaneous resolution after withdrawal of treatment. Large-scale cohort studies reveal that IFNs are associated rarely with neurologic complications, and only one previous report has linked IFN-alpha therapy and Bell's palsy. We postulate that IFN-alpha therapy led to a breakdown of peripheral tolerance to myelin sheath antigens, leading to neuropathy, just as IFN-alpha therapy can cause autoimmune thyroiditis through breakdown of tolerance to native thyroid antigens.  相似文献   
155.
Primary osteomyelitis of the pubic bone has not been recorded previously. The authors present a case of this unusual entity.  相似文献   
156.
Traditional experimental methods are unable to study the kinematics of whole lumbar spine specimens under physiologic compressive preloads because the spine without active musculature buckles under just 120 N of vertical load. However, the lumbar spine can support a compressive load of physiologic magnitude (up to 1200 N) without collapsing if the load is applied along a follower load path. This study tested the hypothesis that the load-displacement response of the lumbar spine in flexion-extension is affected by the magnitude of the follower preload and the follower preload path. Twenty-one fresh human cadaveric lumbar spines were tested in flexion-extension under increasing compressive follower preload applied along two distinctly different optimized preload paths. The first (neutral) preload path was considered optimum if the specimen underwent the least angular change in its lordosis when the full range of preload (0-1200 N) was applied in its neutral posture. The second (flexed) preload path was optimized for an intermediate specimen posture between neutral and full flexion. A twofold increase in flexion stiffness occurred around the neutral posture as the preload was increased from 0 to 1200 N. The preload magnitude (400 N and larger) significantly affected the range of motion (ROM), with a 25% decrease at 1200 N preload applied along the neutral path. When the preload was applied along a path optimized for an intermediate forward-flexed posture, only a 15% decrease in ROM occurred at 1200 N. The results demonstrate that whole lumbar spine specimens can be subjected to compressive follower preloads of in vivo magnitudes while allowing physiologic mobility under flexion-extension moments. The optimized follower preload provides a method to simulate the resultant vector of the muscles that allow the spine to support physiologic compressive loads induced during flexion-extension activities.  相似文献   
157.
The paraneoplastic autoantibody, collapsin response-mediator protein (CRMP)-5 immunoglobulin G (IgG), is specific for neuronal cytoplasmic CRMP-5, and is usually associated with small-cell lung carcinoma or thymoma. We report on details of a movement disorder that followed anti-B-cell therapy in a patient with lymphoma, and was accompanied by CRMP-5 IgG.  相似文献   
158.
We predicted that children's conceptions of various self-care behaviors and social relations would be related to their degree of experience with insulin dependent diabetes mellitus (IDDM). A total of 55 children were recruited for this study in three experience groups: children with IDDM (high experience), children having a sibling with IDDM (low experience), and normal healthy children (no experience). In line with our model, children with IDDM had a more developed and sophisticated understanding of concepts associated with disease management than did either siblings of children with diabetes or the comparison group; surprisingly, experience with the disease (children with IDDM) was associated with more complex conceptions of social relations as well.  相似文献   
159.
160.
Michaelis constants and maximal velocities for phenylacetaldehyde (a metabolite of phenylethylamine), 3,4-dihydroxyphenylacetaldehyde (a metabolite of dopamine), 5-hydroxyindole acetaldehyde (a metabolite of serotonin), and 3,4-dihydroxyphenylglycolaldehyde (a metabolite of epinephrine and norepinephrine) have been determined for both cytoplasmic (E1) and mitochondrial (E2) isozymes of human liver aldehyde dehydrogenase (EC 1.2.1.3). Kinetic constants with biogenic aldehydes have never been previously determined for individual homogeneous isozymes of aldehyde dehydrogenase from any species. Mathematical treatment of these constants suggests that competition with acetaldehyde during alcohol metabolism would severely inhibit dehydrogenation of biogenic aldehydes with the mitochondrial and not the cytoplasmic isozyme of human liver aldehyde dehydrogenase.  相似文献   
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