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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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Among 750 symptomatic and asymptomatic patients, Dientamoeba fragilis was detected at a prevalence of 5.2% and more common than Giardia intestinalis. Most infected patients presented with diarrhea and abdominal pain with symptoms greater than 2 weeks duration being common. Bacterial and viral causes of infection were excluded by routine microbiological techniques. Treatment of D. fragilis infection with either iodoquinol, paromomycin, or combination therapy resulted in the eradication of the parasite and complete resolution of symptoms. Treatment failure/relapses were associated only with the use of metronidazole. Nineteen patients were examined for pin worm, no Enterobius vermicularis, a proposed vector of transmission, were detected. Intermittent shedding of D. fragilis was found to be highly variable. These studies confirm the pathogenic nature of D. fragilis and we recommend laboratories routinely test for the organism.  相似文献   
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As there is a 10% risk of hypertension developing in children with reflux nephropathy and the renin-angiotensin system has been implicated in its aetiology, a long term prospective study has been undertaken to explore the relationship between plasma renin activity (PRA) and blood pressure in such patients. In 1978, of 100 normotensive children with reflux nephropathy 8% were shown to have PRA above normal. Five years later of 85 subjects suitable for analysis 13% had increased PRA and it was shown that PRA and blood pressure SD scores significantly increased. The present study refers to the 10 year follow up in which 95 of the original group were traced but eight of these were unavailable for study and 28 others were excluded from analysis because of extraneous factors that might influence blood pressure or PRA. Results therefore on 59 have been analysed. PRA was above normal in 13/59 (20%) subjects, and PRA and blood pressure SD scores had further increased. The data continue to support the role of the renin-angiotensin system in the observed rise of blood pressure in reflux nephropathy, but individual PRA measurements do not appear so far to predict reliably the onset of hypertension in affected patients.  相似文献   
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Renovascular disease in childhood.   总被引:4,自引:0,他引:4  
Fifty-four children referred for investigation of hypertension had renovascular disease. In eight patients it was associated with neurofibromatosis, in three with idiopathic hypercalcemia of infancy, and in five cases it followed an arteritic illness. Fibromuscular dysplasia was the underlying abnormality in the majority of cases (46%). Twenty-six patients (48%) were first seen with accelerated hypertension; 38 children (70%) had bilateral renal arterial disease, and in 41 (76%), disease of the small intrarenal vessels was found. Renal vein renin ratios indicated unilateral disease in 31 cases; the results correlated with arteriography findings in 32 (62%) of 51 patients. Eleven children also had the middle aortic syndrome, and 9 of 16 patients, investigated by cerebral arteriography because of cranial bruits or focal neurologic signs, had cerebral vascular abnormalities. Twenty patients were treated surgically--10 by reconstructive procedures, 11 by nephrectomy or heminephrectomy, and 6 by transluminal angioplasty. Of these, 9 (45%) are normotensive with no treatment, 10 have a decreased requirement for antihypertensive drugs, and 1 had no improvement. Thirty-four patients were treated medically because of the extent of their disease; two patients have died of hypertensive complications. We conclude that renal vascular disease in children is often widespread, may be associated with intracerebral vascular disease, frequently affects both kidneys, including both intrarenal and extrarenal vessels, and is therefore not always amenable to surgical intervention and cure.  相似文献   
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Foregut motor function in chronic renal failure.   总被引:3,自引:0,他引:3  
In children with chronic renal failure (CRF) anorexia, nausea, and vomiting are common yet poorly understood symptoms. We studied oesophageal and gastric motor function in 12 children (age 7 months-6.8 years) with severe CRF not undergoing dialysis who had persistent anorexia and vomiting. Eight of 12 patients had significant gastro-oesophageal reflux (reflux index 5.2% to 21.9%, mean 11.3%; controls < 5%), 7/10 had altered gastric half emptying times (T1/2) for 5% glucose or milk (glucose meal--controls: 8-14 min, two CRF patients: 18-25 min; milk meal--controls: 48-72 min, five CRF patients 27, 28, 82, 83, and 110 min). Gastric antral electrical control activity was abnormal in 6/11 patients, with different types of gastric dysrhythmias whereas the remainder and controls showed a regular dominant frequency of 0.05 Hz. In 7/9 patients fasting serum gastrin concentration was raised (53 to > 400, mean 168 pmol/l, controls < 40 pmol/l). All CRF patients with anorexia and vomiting had one or more disorder of foregut motility. The nature and variety of the motor disorders and the raised concentrations of circulating gastrin suggest that the normal environment generated by CRF affects the function of the smooth muscle of the foregut.  相似文献   
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