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The sequence effect (SE) in Parkinson's disease (PD) is progressive slowing of sequential movements. It is a feature of bradykinesia, but is separate from a general slowness without deterioration over time. It is commonly seen in PD, but its physiology is unclear. We measured general slowness and the SE separately with a computer‐based, modified Purdue pegboard in 11 patients with advanced PD. We conducted a placebo‐controlled, four‐way crossover study to learn whether levodopa and repetitive transcranial magnetic stimulation (rTMS) could improve general slowness or the SE. We also examined the correlation between the SE and clinical fatigue. Levodopa alone and rTMS alone improved general slowness, but rTMS showed no additive effect on levodopa. Levodopa alone, rTMS alone, and their combination did not alleviate the SE. There was no correlation between the SE and fatigue. This study suggests that dopaminergic dysfunction and abnormal motor cortex excitability are not the relevant mechanisms for the SE. Additionally, the SE is not a component of clinical fatigue. Further work is needed to establish the physiology and clinical relevance of the SE. © 2010 Movement Disorder Society.  相似文献   
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OBJECTIVE: Yale-Brown-Cornell Eating Disorder Scale (YBC-EDS) scores were assessed in recovered eating disorder patients, restrained dieters, and unrestrained nondieters. METHOD: YBC-EDS interviews were conducted with 53 recovered eating disorder patients who had no symptoms within at least 6 months, 29 restrained dieters, and 36 unrestrained controls. RESULTS: Unrestrained control subjects had no typical eating-disordered preoccupations or rituals. The majority (62%) of restrained dieters did have current eating-disordered preoccupations but only 5 had current eating-disordered rituals. Most recovered eating disorder subjects had no current eating-disordered preoccupations (66%) and 76% had no current eating-disordered rituals. Unrestrained eating controls had significantly lower Preoccupation, Total, and Motivation to Change scores on the YBC-EDS than the other groups and significantly lower Ritual scores than the recovered eating disorder group. There were no significant differences between the restrained dieters and the recovered eating disorder group. DISCUSSION: Recovered eating disorder patients who no longer meet any of the DSM-IV criteria for an eating disorder are similar in severity of eating concern to normal weight restrained eating dieters. Both of these groups have more eating and weight concerns as compared with the unrestrained eating, nondieting controls. The YBC-EDS effectively distinguishes the healthy eating controls from restrained eating dieters and recovered eating disorder patients.  相似文献   
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It has been suggested that proliferation of enterobacteriaceae and/or anaerobes in the duodenum of some children with acute diarrhoea determines whether the episode becomes persistent. A review of published studies and the comparison of cultures of duodenal aspirates from Peruvian children with acute and persistent diarrhoea and diarrhoea-free children did not support this hypothesis. Although many children had enterobacteriaceae and/or anaerobes cultured there was no correlation with clinical and nutritional outcome. Age, nutritional status, the environment and the aetiology of the episode were determinants of the duodenal microflora independent of diarrhoea. Culture of the duodenal aspirates did not increase the yield of enteropathogens which were isolated more frequently from stools than from the duodenum. Despite the presence of a single strain or serotype of enterobacteriaceae suggesting that these bacteria were colonizing the duodenum, we were unable to demonstrate any adherence mechanisms in the majority of them. Two often bacteria with no other evidence of virulence caused diarrhoea in the RITARD rabbit model.  相似文献   
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OBJECTIVE: Fibrous dysplasia (FD) is a skeletal disorder often associated with McCune-Albright syndrome, a rare multisystem disorder caused by GNAS1 gene mutation. FD frequently affects the craniofacial bones, including the maxilla and the mandible; nevertheless, its effects on dental tissues and the implications for dental care remain unclear. The aim of this study was to characterize the dental features associated with FD and the reaction of affected bones to routine dental therapy.Study design Thirty-two patients with FD underwent dental evaluation and endocrine testing as part of the diagnosis of FD/McCune-Albright syndrome. Any dental anomalies were recorded, and the associations between endocrinopathies and dental anomalies were analyzed statistically by means of the paired t test. RESULTS: Eighty-four percent had FD in the maxilla and/or mandible; endocrine dysfunction; and/or renal phosphate wasting. The caries index scores were 2.9 (ages 4-17 years) and 9.6 (ages 18-50 years). Malocclusion (81%) and other prevalent dental anomalies (41%) included tooth rotation, oligodontia, and taurodontism. The expansion of the maxilla or mandible by FD did not distort the dental arch curvature, and routine dental therapies such as extractions, restorations, and orthodontic treatment did not exacerbate FD lesions. CONCLUSION: Maxillomandibular FD was associated with higher rates of caries and malocclusion than were present in healthy patients. Furthermore, patients with FD did not require special dental management and were able to undergo routine dental care without an exacerbation of FD lesions.  相似文献   
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BACKGROUND: Lung development is sensitive to physiological stresses, and its development may be impaired by physical distortion, as in patients with congenital diaphragmatic hernia. Yet, little is known about how mechanical forces can influence lung morphogenesis. Studies with cultured cells suggest that cytoskeletal tension may play a key role in growth control. Since the small GTPase Rho plays an important role in the control of cell tension generation, we carried out studies to test the hypothesis that changes in Rho-mediated cell tension may influence branching morphogenesis. METHODS: Embryonic lung buds from timed pregnant Swiss Webster mice were microdissected on Embryonic Day 12 (E12), and whole organs were cultured in serum-free medium in the presence of the Rho activator cytotoxic necrotizing factor 1 (CNF-1) for 48 h. Serial measurements of the degree of epithelial branch formation and tissue maturation were performed using light microscopy and computerized image analysis. RESULTS: At 48 h, embryonic lungs treated with 2 ng/ml CNF-1 increased their terminal bud count by 236 +/- 18% (P = 0.01) compared with 132 +/- 2% for untreated controls. However, dose-response experiments revealed biphasic behavior: at a higher dose of CNF-1 (200 ng/ml), bud number was actually decreased relative to controls (43 +/- 1%, P < 0.001). Histological analysis revealed that individual glands appeared to be more highly developed at low-dose CNF-1, whereas the high dose produced gland contraction. CONCLUSIONS: These data support a potential role for Rho and cytoskeletal tension in control of epithelial pattern formation during lung development.  相似文献   
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The mortality and morbidity after hip and knee arthroplasty were reviewed retrospectively during a 3-year period in 14 patients who had chronic renal failure and who were receiving hemodialysis. The patients had a primary total hip or knee replacement, or a revision arthroplasty or resection arthroplasty. Four of the patients (29%) died in the hospital during the postoperative period. One of the seven patients (14%) having a primary joint replacement died, whereas three of the seven patients (86%) having a revision or resection died. Every patient had multiple medical comorbidities, and every patient had a complication. The results indicate that arthroplasty procedures, especially revisions and resections, in this patient population are associated with a high rate of complications and death, and that in-depth informed consent should be provided for all patients contemplating these procedures. Meticulous treatment of medical comorbidities is mandatory. Finally, data in the literature and in the current report question whether joint arthroplasty procedures should be done in patients with end-stage renal disease who are receiving hemodialysis.  相似文献   
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