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41.
Summary The cerebral changes are described in a woman of 54 who suffered from Binswanger's encephalopathy: there were no signs or symptoms of chronic arterial hypertension. The disease presented as dementia of about 3 years duration. Computed tomography of the brain 2. 5 years before her death showed bilateral widespread hypodense lesions in the cerebral white matter. She died of an asthmatic attack. Autopsy disclosed extensive bilateral degeneration of the central white matter, lacunes and gliosis. Severe obliterative arteriolosclerosis occurred in the meningeal vessels and those supplying the affected parts of the brain. Light microscopy showed that the most severe lesions occurred in the arterioles. Immunohistochemistry demonstrated profound extravasation of plasma proteins chiefly albumin, indicating dysfunction of the blood-brain barrier. Thus, the lesions characteristic of Binswanger's encephalopathy may develop in the absence of chronic arterial hypertension. Additional pathogenic factors, possibly genetic predisposition to vascular injury may play a role in the development of this condition.Supported by grants from the Swedish Medical Research Council, Project No 12X-03020 and 1987 Års Stiftelse för Strokeforskning 相似文献
42.
Differences between control and focal hand dystonia (FHD) subject groups in short interval intracortical inhibition (SICI) as determined by paired transcranial magnetic stimulation (TMS) can be difficult to demonstrate, due to interindividual differences. The purpose of this study was to compare two TMS methods for assessing SICI in 8 control and 7 FHD subjects. Electromyographic (EMG) data were recorded from the first dorsal interosseous (FDI) muscle of the dominant hands of the control subjects and affected hands of the FHD subjects. The first method used a conventional approach of setting conditioning stimulus intensity to 80% of rest threshold (RTh) and test stimulus intensity to 120% RTh. Three interstimulus intervals (ISIs) were used: 2 msec, 3 msec, and the ISI between 2 and 3 msec that produced optimal SICI. The second method was novel in that test stimulus intensity was set to 150% active threshold (ATh), and conditioning stimulus intensity was varied between 50% and 100% ATh. The latter was determined at the threshold for SICI and expressed as a ratio of ATh. There was no difference between the subject groups in the degree of SICI produced using the first method, at the three ISIs studied. However, using the second method, the SICI threshold:ATh ratio was found to be significantly higher for FHD subjects. This finding suggests that determining the SICI threshold:ATh ratio may be a more sensitive measure of intracortical inhibitory function than more conventional methods. 相似文献
43.
Shyamal K Das Tapas K Banerjee Atanu Biswas Trishit Roy Deepak K Raut Arijit Chaudhuri Abhijit Hazra 《Movement disorders》2007,22(14):2031-2036
An epidemiological study on dystonia has not been reported from India. As part of a major study to find out the prevalence of major neurological disorders in the large urban city of Kolkata, Eastern India, we planned to determine the prevalence of primary dystonia. The study design was a cross-sectional study of a sample population obtained through stratified random selection and conducted in a two-stage procedure of screening by a nonprofessional team followed by confirmation of screened positive cases by the study neurologist. A total population of 52,377 was screened, and 29 subjects with dystonia were diagnosed. Out of them 23 subjects had primary dystonias [crude prevalence rate (CPR), 43.91/100,000; 95% confidence interval (CI), 28.41-64.81; age-standardized rates to world standard population, 49.06 (95% CI,31.74-72.41)] and all cases were focal type and predominantly of limb dystonia variety. Mean onset of dystonias were earlier in women (43.5 years) as compared to men (46.6 years). Thus our study on primary dystonia shows higher prevalence when compared with that of many studies globally, predominantly of focal type, earlier onset among women, and more cases of limb dystonias when compared with more prominent blepharospasm and cervical dystonias in western reports. 相似文献
44.
E. M. Fredericks M. J. Lopez J. C. Magee V. Shieck L. Opipari-Arrigan 《American journal of transplantation》2007,7(8):1974-1983
The present study empirically assessed the relationships between adherence behaviors and HRQOL, parent and child psychological functioning and family functioning, and investigated the relationship between adherence behaviors and health outcomes in children who were within 5 years of their liver transplantation. Participants included 38 children (mean = 8.5 years, range 28 months to 16 years) and their parent/guardian(s). HRQOL and psychological functioning were examined using well-validated assessment measures. Measures of adherence included the rate of clinic attendance and standard deviations (SDs) of consecutive tacrolimus blood levels, which were collected and evaluated retrospectively. Measures of child health status included the frequency of hospital admissions, liver biopsies, episodes of rejection and graft function for the year prior to study participation. Results indicated that nonadherence was related to lower physical HRQOL, more limitations in social and school activities related to emotional and behavioral problems, parental emotional distress and decreased family cohesion. Nonadherence was also related to frequency and duration of hospitalizations, liver biopsies and rejection episodes. These results suggest that empirically based assessment of HRQOL, parenting stress and family functioning may help identify patients at risk for nonadherence, and may allow for the need-based delivery of appropriate clinical interventions. 相似文献
45.
J. F. Trotter J. Olson J. Lefkowitz A. D. Smith R. Arjal J. Kenison 《American journal of transplantation》2007,7(6):1624-1628
Priority for liver transplantation is based on the Model for Endstage Liver Disease (MELD) score, a mathematical function which includes international normalized ratio (INR). We present an analysis to determine the lab-to-lab variation in INR at 14 clinical laboratories across the United States. We performed a survey to identify representative clinical laboratories across the United States, where INR was measured in the determination of MELD score. Five 'standard' samples for INR were formulated and were sent to the 14 clinical laboratories to determine variation in INR and MELD score. Among the 14 clinical laboratories, the range in INR for the five samples was: sample 1 (1.2-2.0), sample 2 (1.4-2.5), sample 3 (1.7-3.4), sample 4 (1.9-3.7) and sample 5 (2.4-5.1). The range in calculated MELD score was: sample 1 (8-14), sample 2 (10-17), sample 3 (12-20), sample 4 (14-21) and sample 5 (16-25). The selection of the clinical laboratory used to determine INR may result in substantial changes in MELD score independent of severity-of-illness. These data suggest that further review of interlaboratory variation in MELD should be undertaken because of the potential impact on prioritization for liver transplantation. 相似文献
46.
目的探讨在肝肥大-萎缩征中肥大肝叶内胆管结石的处理方法。方法回顾性分析我科1990年6月~2004年12月收治的103例肥大肝叶内胆管结石病人的临床资料,总结其手术治疗的原则和方法。结果全体病例均经手术治愈,术后残石率17.5%,效果优良率83.7%。结论肥大肝叶内的胆管结石,手术难度大,应根据病情选择手术方式,既要遵循肝胆管结石的治疗原则,又要保护赖以生存的肥大肝叶(段)。 相似文献
47.
Eugene L. Dela Cruz DPM FACFAS Greg R. Brockbank DPM 《The Journal of foot and ankle surgery》2005,44(4):311-312
Talar dome lesions greater than 1 cm in diameter are often treated with ankle joint mosaicplasty. The purpose of this article is to present the use of a noninvasive ankle distractor that can improve access to the talus when used with a malleolar osteotomy. The use of the distractor allows for graft insertion at a more appropriate angle in relationship to the talar cartilage, avoidance of invasive distractor usage, and potential use of a smaller osteotomy. 相似文献
48.
Hector Rodriguez-Luna Hugo E. Vargas Adyr Moss Kunam S. Reddy Richard B. Freeman David Mulligan 《American journal of transplantation》2005,5(9):2244-2247
The Model for End-Stage Liver Disease (MELD) is used to assign priority for liver transplantation candidates. The Organ Procurement and Transplantation Network (OPTN) approved recognized exceptional diagnoses (RED's) for which MELD fails to accurately measure priority. Centers can request increased MELD points in cases not recognized by this policy (non-RED's). Our aim was to compare regional practices to justify non-RED requests for MELD adjustments. The UNOS/OPTN database was queried to extract all adult cases for which a non-RED MELD adjustment was requested from 2/27/02 until 8/27/03. The data were stratified by region and justification. Data for 29,510 listings were available. 26,947 had complete diagnosis information. There were 827 non-RED requests of which 477 (57.7%) petitions were approved by the regional review boards (RRBs). The approval rate varied significantly among regions (range: 28-75%, p<0.0001). The most common non-RED's were complications of portal hypertension (48%). The percentage of patients listed with non-RED's varied significantly among regions (0.7-8.3 %, p<0.0001), as did the proportion of patients transplanted with non-RED's (2.1-31.9%, p<0.0001). Demographics did not differ among regions requesting non-REDs.Widespread regional variations exist in the handling of requests for non-REDs. These variations point to the need for reform to standard exception criteria. 相似文献
49.
C. Bourdeaux A. Darwish J. Jamart T.T. Tri M. Janssen J. Lerut J.-B. Otte E. Sokal J. de Ville de Goyet R. Reding 《American journal of transplantation》2007,7(2):440-447
Timely access to a living donor (LD) reduced pretransplant mortality in pediatric liver transplantation (LT). We hypothesized that this strategy may provide better posttransplant outcome. Between July 1993 and April 2002, 235 children received a primary LT from a LD (n = 100) or a deceased donor (DD) (n = 135). Demographic, surgical and immunological variables were compared, and respective impact on posttransplant complications was studied using a multivariate analysis. Five-year patient survival rates were 92% and 85% for groups LD and DD, respectively (p = 0.181), the corresponding graft survival rates being 89% and 77% (p = 0.033). At multivariate analysis: (1) type of donor (DD) was correlated with higher rate of artery thrombosis (p < 0.012); (2) biliary complication rate at 5 years was 29% and 23% for groups LD and DD, respectively (p = 0.451); (3) lower acute rejection incidence could be correlated with type of donor (DD) (p = 0.001), and immunosuppressive therapy (tacrolimus) (p < 0.001). We conclude that (1) according to the multivariate analysis, LT with LD provided similar patient and graft outcome, when compared to DD; (2) a higher rate of artery thrombosis and a lower rate of rejection were observed in group DD; (3) this study confirms the efficacy of tacrolimus for immunoprophylaxis, whatever the type of organ donor is. 相似文献
50.
A case study is presented in which a focal hand dystonia seems to have developed in the right hand of a classical guitarist as a result of a neuromuscular peripheral defect caused by trauma. The trauma was a near total perforation of the first web space by a splinter. Healing was uneventful without apparent functional complications. Two years later the patient noticed difficulties in extending the index in playing, for which he received various unsuccessful treatments during seven years. However, we found more severe dystonic symptoms (cocontractions) in the thumb than in the index during playing, which correlated with an undiagnosed insufficiency in the flexor pollicis brevis (FPB). This defect allowed proposing a biomechanical analysis of compensations for diminished thumb control in playing, which would explain the dysfunction in the index in playing as overcompensation for the thumb problem. If this analysis is correct, the etiology of the case can be traced back to underlying multiarticular control problems in the thumb caused by an insufficient FPB. This defect was considered irrepairable. It was concluded that even with knowledge of the underlying cause, a potentially successful treatment of the dystonia might not exist in this case. The case would demonstrate that task-specific hand dystonias can arise as overcompensations for (peripheral) neuro-musculoskeletal defects. The case is illustrated by videos of playing and functional thumb tests. 相似文献