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BackgroundIn vagal nerve stimulation (VNS) therapy, the release of VNS model 106 (AspireSR) allowed for responsive VNS (rVNS). rVNS utilizes a cardiac-based seizure detection algorithm to detect seizure-induced tachycardia to trigger additional stimulation. There are some studies suggesting clinical benefits of rVNS over traditional VNS, but the performance and significance of autostimulation mode in clinical practice are poorly understood.ObjectivesTo assess the effect of initiation of rVNS therapy and altered stimulation settings on the number of daily stimulations and energy consumption in VNS therapy and to compare autostimulation performance in different epilepsy types.Materials and MethodsRetrospective follow-up of 30 patients with drug-resistant epilepsy treated with rVNS including 17 new implantations and 13 battery replaces at a single center in Finland. Our data consist of 208 different stimulation periods, that is, episodes with defined stimulation settings and both autostimulation and total stimulation performance-related data along with clinical follow-up.ResultsThe variation in autostimulation frequency was highly dependent on the duration of the OFF-time and autostimulation threshold (p < 0.05). There was a large additional effect of autostimulation mode on therapy time and energy consumption with longer OFF-times, but a minor effect with shorter OFF-times. Significantly more autostimulations were triggered in the temporal lobe and multifocal epilepsies than in extratemporal lobe epilepsies.ConclusionsThe initiation of autostimulation mode in VNS therapy increased the total number of stimulations. Shortening the OFF-time leads to a decreased number and share of automatic activations. Epilepsy type may affect autostimulation activity.  相似文献   
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Several cell lines secreting monoclonal antibodies (Mabs) against a major forebrain synaptic membrane (SM) glycoprotein, gp 50, have been raised. Western blots show that the Mabs react with a polypeptide doublet of Mrs 49 and 45 kDa. These polypeptides exist solely in a concanavalin A (Con A) binding form. Removal of the Con A receptors by digestion with endo-beta-N-acetylglucosaminidase H (endo H) lowers the Mrs of the glycoprotein doublet to 36.5 and 34 kDa. Western blots of 2D polyacrylamide gels indicate that gp 50 exists in several isoforms. Solid phase radioimmunoassay (RIA) and Western blots of brain subcellular fractions show the antigenic material to be concentrated in the SM fraction, but to be present in much lower amounts in synaptic junctions and postsynaptic densities. Gp 50 appears to be brain specific. Regional distribution studies show that it is present in all brain regions but is two-fold concentrated in cerebellum, brainstem and midbrain compared to forebrain. Immunocytochemical studies of several brain regions show that gp 50-like immunoreactivity is neuron specific and is concentrated in selected neuronal species, particularly granule cells. In both cerebellar and hippocampal granule cells gp 50-like immunoreactivity is localized in the perikarya and primary dendrites. Though immunocytochemistry did not show staining of synaptic regions this may be due to masking of the reactive epitope. The results are discussed in terms of the molecular properties of gp 50 and its subcellular localization in brain tissue.  相似文献   
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Immunologic contact urticaria to fish   总被引:1,自引:0,他引:1  
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Background  

Total hip arthroplasty is a successful surgery, that fails at a rate of approximately 10% at ten years from surgery. Causes for failure are mainly aseptic loosening of one or both components partially due to wear of articular surfaces and partially to design. The present analysis aimed to identify risk factors and quantify their effects on aseptic failure.  相似文献   
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PURPOSE: This study aims to determine the effect of loss of breast cancer metastasis suppressor 1 (BRMS1) protein expression on disease-free survival in breast cancer patients stratified by estrogen receptor (ER), progesterone receptor (PR), or HER2 status, and to determine whether loss of BRMS1 protein expression correlated with genomic copy number changes. EXPERIMENTAL DESIGN: A tissue microarray immunohistochemical analysis was done on tumors of 238 newly diagnosed breast cancer patients who underwent surgery at the Cleveland Clinic between January 1, 1995 and December 31, 1996, and a comparison was made with 5-year clinical follow-up data. Genomic copy number changes were determined by array-based comparative genomic hybridization in 47 breast cancer cases from this population and compared with BRMS1 staining. RESULTS: BRMS1 protein expression was lost in nearly 25% of cases. Patients with tumors that were PR negative (P=0.006) or HER2 positive (P=0.039) and <50 years old at diagnosis (P=0.02) were more likely to be BRMS1 negative. No overall correlation between BRMS1 staining and disease-free survival was observed. A significant correlation, however, was seen between loss of BRMS1 protein expression and reduced disease-free survival when stratified by either loss of ER (P=0.008) or PR (P=0.029) or HER2 overexpression (P=0.026). Overall, there was poor correlation between BRMS1 protein staining and copy number status. CONCLUSIONS: These data suggest a mechanistic relationship between BRMS1 expression, hormone receptor status, and HER2 growth factor. BRMS1 staining could potentially be used in patient stratification in conjunction with other prognostic markers. Further, mechanisms other than genomic deletion account for loss of BRMS1 gene expression in breast tumors.  相似文献   
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BACKGROUND: Recent research has addressed the issue of subtyping juvenile bipolar disorder (JBD). Accordingly, we set out to find out, in a naturalistic sample of bipolar children and adolescents with mania and mixed mania, whether the most useful subtyping should be based on clinical features (elated vs. irritable) or course (episodic vs. chronic). METHODS: We studied 136 patients, 81 male patients (59.6%) and 55 female patients (40.4%), mean age 13.5 +/- 2.9 years, meeting the DSM-IV diagnosis of bipolar disorder, assessed by a structured clinical interview (Schedule for Affective Disorders and Schizophrenia for School-Age Children-Present and Lifetime Version [K-SADS-PL]). RESULTS: Regarding course, 77 patients (56.6%) had an episodic course and 59 patients (43.4%) had a chronic course. Patients with chronic course were significantly younger, had an earlier onset of JBD, and presented a more frequent comorbidity with disruptive behavior disorders. According to the prevalent mood disturbance, 75 patients (55.1%) showed an elated and 61 patients (44.9%) showed an irritable mood. Elated mood was more frequent in patients with episodic course, whereas irritable mood was more frequent in the patients with chronic course. CONCLUSIONS: These findings suggest that chronic versus episodic course may be a putative differential feature. Further validation of such a distinction would require prospective studies, temperament evaluation, gender and neurobiologic approaches, and differential psychopharmacologic assignment and response.  相似文献   
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The European Society of Thoracic Surgeons (ESTS) organized a workshop dealing with lymph node staging in non-small cell lung cancer. The objective of this workshop was to develop guidelines for definitions and the surgical procedures of intraoperative lymph node staging, and the pathologic evaluation of resected lymph nodes in patients with non-small cell lung cancer (NSCLC). Relevant peer-reviewed publications on the subjects, the experience of the participants, and the opinion of the ESTS members contributing on line, were used to reach a consensus. Systematic nodal dissection is recommended in all cases to ensure complete resection. Lobe-specific systematic nodal dissection is acceptable for peripheral squamous T1 tumors, if hilar and interlobar nodes are negative on frozen section studies; it implies removal of, at least, three hilar and interlobar nodes and three mediastinal nodes from three stations in which the subcarinal is always included. Selected lymph node biopsies and sampling are justified to prove nodal involvement when resection is not possible. Pathologic evaluation includes all lymph nodes resected separately and those remaining in the lung specimen. Sections are done at the site of gross abnormalities. If macroscopic inspection does not detect any abnormal site, 2-mm slices of the nodes in the longitudinal plane are recommended. Routine search for micrometastases or isolated tumor cells in hematoxylin-eosin negative nodes would be desirable. Randomized controlled trials to evaluate adjuvant therapies for patients with these conditions are recommended. The adherence to these guidelines will standardize the intraoperative lymph node staging and pathologic evaluation, and improve pathologic staging, which will help decide on the best adjuvant therapy.  相似文献   
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After a number of years of evolutionary changes to the New Zealand health system, the government announced a radical restructuring of all publicly funded health services in July 1991, to be implemented on 1 July 1993. The primary features of these changes are a splitting of the purchaser and provider roles, and a restructuring of health services along more business-like lines. The proposals have been highly contentious and have attracted little support from within the health sector. This paper outlines the reasons for and nature of the reforms and explores some of the issues behind the changes. These include problems of pricing services for purchasing purposes, the potential conflict between financial and social objectives, and questions of accountability of purchasers and providers. Considerable uncertainty surrounding these and other issues means that any potential efficiency gains cannot be guaranteed. The costs of the reform process have, however, already been high, both in financial terms and in terms of their impact on the morale of health workers.  相似文献   
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