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51.
Hyperexcitability of the motor system has been reported in Parkinson's disease (PD). We evaluate how cutaneous afferents modulate motor excitability in PD patients and whether abnormal modulation is correlated to parkinsonian symptoms. Digital stimulation causes abnormal enhancement of motor responses in patients. This effect may be one of the features of motor hyperexcitability in PD. Cutaneomotor hyperexcitability correlates with clinical scores, suggesting that abnormal processing of cutaneous inputs might contribute to the pathogenesis of parkinsonian symptoms.  相似文献   
52.
Autoantibodies to centromere proteins (anti-CENPs) and to topoisomerase-I are highly specific for scleroderma. Unlike most autoantibodies in other diseases, these autoantibodies are mutually exclusive. We have analysed the idiotypes (Ids) expressed by anti-CENP-B, antitopoisomerase-I, and IgGs from 20 scleroderma patients. Rabbit anti-Ids were prepared to antitopoisomerase-I from two scleroderma patients, and to anti-CENP-B from four patients. These six anti-Ids were used to study the purified autoantibodies from 20 scleroderma patients: four antitopoisomerase-I, 10 anti-CENP-B, and six purified IgG from scleroderma patients who were negative for both autoantibodies. In addition, we studied sera from 40 normal autoantibody-negative controls, and sera and purified immunoglobulins from 17 systemic lupus erythematosus (SLE) patients containing high titres of anti-double-stranded DNA, and/or autoantibodies to extractable nuclear antigens (ENA). Using direct binding, and competitive inhibition ELISAs and immunoblots, we identified an Id present in the heavy chains of all the affinity-purified antitopoisomerase-I, and anti-CENP-B. Interestingly, this Id was also present in the immunoglobulins of the scleroderma patients who had neither of the two autoantibodies. By contrast, cross-reactive Id-EM was not found in the sera or immunoglobulins from 17 SLE patients, or in the sera from 40 normal subjects. Several samples from two patients showed that this cross-reactive Id-EM was stable over time. The scleroderma disease-specific autoantibodies may be identified through a common structural feature at the variable region of the heavy chain: cross-reactive Id-EM.  相似文献   
53.
This study investigated whether domperidone could improve gastrointestinal symptoms in patients with Parkinson's disease who were receiving levodopa therapy. A total of 11 patients were studied. Following a baseline gastric emptying test, patients were treated with a starting dose of domperidone 20 mg p.o. q.i.d. A follow-up gastric emptying test was repeated at least 4 months after starting domperidone therapy. At the beginning and at each 3-month follow-up visit, symptoms of nausea, vomiting, anorexia, abdominal bloating, heartburn, regurgitation, dysphagia, and constipation were evaluated and scored on a scale of 0–3. The overall mean follow-up period was 3 years. Compared with their baseline evaluation, patients experienced a significant improvement in all symptoms (p < 0.05) except dysphagia and constipation. Gastric emptying of an isotope-labeled solid meal was significantly faster, with a baseline result of 60.2 ± 6.4% retention of isotope 2 h after the meal compared with 37.0 ± 2.2% retention during domperidone therapy (p < 0.05). Patients' global assessment of Parkinson's disease remained stable or improved. Serum prolactin was elevated in all patients after domperidone therapy (p < 0.05). Domperidone therapy significantly reduces upper gastrointestinal symptoms and accelerates gastric emptying of a solid meal, but does not interfere with response to antiparkinsonism treatment.  相似文献   
54.
Head injury in children causes special concern in most communities. From 1989 to 1994, 2,785 children younger than 16 years old were admitted to our neurosurgical service because of head injury. Fall from a height was the major cause of head injury leading to admission in infants and children in preschool age groups, whereas traffic-related or bicycle-related accidents were more likely to be the cause of head injury for those aged 11–15 years. In all age groups there was a male preponderance. The overall mortality was 0.6%. Traffic-ralated accidents caused more severe injury and accounted for 67% of all fatalities. For patients under 6 years old, about 40% of head injuries occurred at home. Preventive measures for pediatric head injury in Hong Kong are suggested.  相似文献   
55.
56.
This study examined the mitogenic response to keratinocyte growth factor (KGF) of normal and tumour-derived human oral keratinocytes in which the degree of cellular differentiation was known and in contiguous fibroblast cultures derived from the malignant epithelial cultures. Keratinocytes, but not fibroblasts, were stimulated by KGF. There by demonstrating epithelial target cell specificity of the ligand. KGF-induced stimulation of the tumour-derived keratinocytes cultured in the absence of the 3T3 fibroblast support broadly correlated with the degree of cellular differentiation; well-differentiated keratinocytes were stimulated more by KGF than their less differentiated counterparts. Malignant oral keratinocytes expressed KGF cell surface receptors (KD 451-709 pM; receptors/cell 2306-413645), but KGF receptor mRNA did not correlate with either KGF-induced mitogenesis or the degree of epithelial cell differentiation. When the tumour-derived keratinocytes were cultured in the presence of 3T3 fibroblasts, the mitogenic response to KGF was comparable to normal epithelial cells. The results suggest that KGF-mediated growth stimulation may not be significant in providing a selective advantage for the growth of malignant keratinocytes.  相似文献   
57.
We conducted a case-control study of the alpha-synuclein-interacting protein gene (SNCAIP, also known as synphilin-1) and Parkinson's disease (PD). A total of 319 PD cases and 195 controls were genotyped for four SNCAIP variants, including a microsatellite repeat in intron 4 and three restriction fragment length polymorphisms (RFLP) proximal to the 5' terminal of exons 1, 4, and 6. None of the variants were found associated with PD overall. Global score statistics were not significant for four, three, and two loci haplotypes. All four loci were in linkage disequilibrium for cases, controls, or both groups combined (P < 0.0001). Recursive partitioning showed no interactions between variants of the SNCAIP gene and variants of the alpha-synuclein gene (SNCA) or the parkin (PARK2) gene.  相似文献   
58.
Restless legs syndrome in Parkinson's disease: a case-controlled study.   总被引:5,自引:0,他引:5  
Restless legs syndrome (RLS) is a disorder of motor activity with a circadian pattern, occurring frequently in patients with Parkinson's disease (PD). We sought to estimate the prevalence of RLS in Indian PD patients. One hundred twenty-six consecutive PD patients and 128 healthy age- and sex-matched controls were evaluated using a predesigned questionnaire. RLS was present in 10 of 126 cases of PD (7.9%) and 1 of 128 controls (0.8%, P = 0.01). PD patients with RLS were older than those without RLS (63.70 +/- 7.80 years vs. 57.37 +/- 10.04 years; P = 0.05) and had higher prevalence of depression (40% vs. 10.3%; P = 0.023). No demographic factors or factors related to PD correlated with the presence or severity of RLS. RLS is more common among patients with PD than controls. A greater medical recognition of this disorder is needed in view of available effective treatment.  相似文献   
59.
Background : A retrospective analysis of 103 case records from 1978 to 1996 with a provisional diagnosis of Buerger's disease was undertaken at the Department of Surgery, University of Hong Kong, Queen Mary Hospital. The aim of the study was to elucidate the clinical course and evaluate the results of surgical intervention of Buerger's disease in Hong Kong Chinese people. Methods : Fourteen patients were subsequently excluded from the study because of inability to fulfil our diagnostic criteria. Data on clinical presentation, investigations, indications and results of surgical intervention were reviewed. Sympathectomies and arterial reconstructions were performed on 42 and four patients, respectively, for critical ischaemia or rest pain. Outcome was analysed with respect to the rate of ulcer healing, pattern of recurrence and limb loss. Results : The patients were all young male heavy smokers with a mean age of 36.5 years. The majority of patients (80%) presented with ischaemic ulceration or gangrene. Vascular reconstruction was undertaken in four patients and satisfactory long-term results were obtained in three patients. Sympathectomy was able to relieve symptoms in 87% of operated patients and ischaemic ulceration healed in 2.6 (mean) ± 1.7 (SD) months after the operation. If the patient continued to smoke, surgical intervention did not exempt the patient from a relapse or amputation. Conclusion : Sympathectomy provides short-term pain relief and promotes ulcer healing in patients with Buerger's disease but carries no long-term benefit. Complete abstinence from smoking is the only means of arresting the progression of the disease.  相似文献   
60.
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