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Asymmetric acetylcholinesterase (AChE) is anchored to the basal lamina (BL) of cholinergic synapses via its collagenic tail, yet the complement of matrix receptors involved in its attachment remains unknown. The development of a novel overlay technique has allowed us to identify two Torpedo BL components that bind asymmetric AChE: a polypeptide of approximately 140 kDa and a doublet of 195-215 kDa. These were found to stain metachromatically with Coomassie blue R-250, were solubilized by acetic acid, and were sensitive to collagenase treatment. Upon sequence analysis, the 140 kDa polypeptide yielded a characteristic collagenous motif. Another AChE-binding BL constituent, identified by overlay, corresponded to a heparan sulfate proteoglycan. Lastly, we established that this proteoglycan, but not the collagenous proteins, interacted with at least one heparin binding domain of the collagenic tail of AChE. Our results indicate that at least two BL receptors are likely to exist for asymmetric AChE in Torpedo electric organ.  相似文献   
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BACKGROUND: Clinical trials have been performed to compare with standard heparin a once or a twice daily regimen of low-molecular-weight heparin but no direct comparison has been done between these two low-molecular-weight heparin regimens in terms of efficacy and safety with a long-term clinical evaluation. METHODS: Patients with proximal deep vein thrombosis, confirmed by venography were randomly assigned to either nadroparin (10,250 AXa IU/ml) twice daily or nadroparin (20,500 AXa IU/ml) once daily for at least 5 days. Regimens were adjusted to bodyweight. Oral anticoagulants were started on day 1 or 2 and continued for 3 months. Patients were followed up for 3 months. The composite outcome of venous thromboembolism and death possibly related to pulmonary embolism was the primary measure of efficacy. Major bleeding was the principal measure of safety. The study was designed to show equivalence between the two regimens. RESULTS: Recurrent thromboembolic events or death possibly related to pulmonary embolism were reported in 13 patients in the once daily group (4.1%) and in 24 patients of the twice daily group (7.2%): (absolute difference 3.1% in favor of the once daily regimen; 95% confidence interval -6.6%, +0.5%). Major bleeding episodes during nadroparin treatment occurred in 4 (1.3%) and 4 patients (1.2%) in the once and twice daily groups, respectively. CONCLUSIONS: A nadroparin regimen of one injection per day is at least as effective and safe as the same total daily dose divided over two injections for the treatment of acute deep vein thrombosis.  相似文献   
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Prognostic factors for survival of 62 fetuses and neonates with nonimmune hydrops fetalis (NIHF) were studied retrospectively. Twenty-eight infants survived >/=28 days which is 45% for all fetuses and newborns diagnosed with NIHF and 61% for liveborns with unresolved NIHF. Univariate analysis identified that mortality was associated with the presence of >/=2 serous cavity effusions and a need for chest compressions at birth. Multivariate logistic regression analysis confirmed that the presence of >/=2 serous cavity effusions was significantly associated with mortality from NIHF <28 days after birth [OR = 48.2 (CI 3.6, 662.9) (p < 0.004)]. We conclude that, compared to published cases from the 1970s and early 1980s, survival of liveborns with NIHF seems improved. The decrease in stillbirths is more notable. The severity of hydrops at birth is the key determinant for survival.  相似文献   
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Provides information about issues confronting neuropsychologists involved in brain injury litigation. Neuropsychologists are often involved as experts in the litigation process because of their unique role in assessment and treatment of brain injury sequelae. Focus is on evaluation, preparation of reports, testimony, professional credibility, ethics, and responsibilities to the patient. Criteria for evaluating the expertise and credentials of psychologists hired by attorneys are presented. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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BACKGROUND: Angiogenesis is an essential process required for growth and metastasis in cancer. In breast, gastric, and prostate cancer, vascular endothelial growth factor (VEGF) has been implicated in angiogenesis; however, little is known about VEGF in HNSCC. In this study, we hypothesize that VEGF is present in elevated levels in HNSCC and may therefore play a role in promoting angiogenesis. METHODS: We obtained tumor tissue from 63 HNSCC patients undergoing primary resection. All tissue samples were analyzed by immunohistochemistry (IHC) techniques for the presence and localization of VEGF; however, only 36 had sufficient amounts of tissue for quantitative analysis of VEGF by ELISA. Nine control specimens taken from patients undergoing uvulopalatopharyngoplasty were also analyzed. RESULTS: In all 63 of our patient samples we found VEGF to be present and localized to the cancer cells and endothelial cells. The poorly differentiated cancer cells stained more intensely in comparison with the well-differentiated ones. There was a 20-fold increase in the patient levels when compared with controls levels (P > or =0.05). Analysis by enzyme-linked immunosorbent assay revealed elevated mean levels of VEGF (241 +/- 326 pg/mg total protein [TP]) with a range of 2 to 1484 pg/mg TP. The control specimens had mean levels of 13 +/- 11 pg/mg TP and a range of 1 to 78 pg/mg TP. Patients who exhibited higher levels of VEGF tended to have a higher rate of disease recurrence (P < or =0.048) and shorter disease-free interval (P < or =0.05). CONCLUSIONS: The expression of VEGF in elevated levels in the HNSCC tumor microenvironment appears to be associated with more aggressive disease. Based on our results, VEGF may be an important angiogenic factor associated with cancer cells and endothelial cells in HNSCC. Further studies are needed to better define the role of VEGF in HNSCC and its role as a potential target for therapeutic intervention.  相似文献   
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OBJECTIVE: To examine differences in family and patient evaluation of neurobehavioral functioning in adults with traumatic brain injury (TBI). DESIGN: Differences were examined by conducting 70 paired sample t tests on scale items and 6 paired sample t tests on scale scores from a neurobehavioral inventory. SETTING: Medical center outpatient clinic. PARTICIPANTS: Three hundred one consecutive adult patients with TBI and 301 informants, primarily family members, completed the neurobehavioral inventory. MAIN OUTCOME MEASURE: Neurobehavioral Functioning Inventory (NFI) comprised of six scales with items describing symptoms and daily living problems. RESULTS: Paired t test analyses of the six scales indicated that patients reported a significantly greater level of communication problems than did their matched family members. No differences were found for the other five scales. Paired t test analyses of the 70 scale items revealed significant differences in patient and family ratings for only 13 items. In all 13 instances, patients reported greater levels of dysfunction than were reported by their family members. Analysis of variance (ANOVA) indicated a main effect of injury severity for only the Communication and Memory/Attention scales. CONCLUSIONS: Findings indicate general agreement between family members and patients regarding patients' everyday problems. Results do not support contentions that patients tend to underestimate difficulties. Agreement levels appear related to injury severity, item specificity, and item content. More research is needed to identify other variables relating to agreement levels, including age, injury severity, and amount of contact between patients and family members.  相似文献   
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DESC+ + (Discrete Event Simulation package using C+ +) has been developed as an object-oriented tool for quantitative simulation studies of communication protocols and architectures of telecommunication networks. The main issue of such performance studies is to secure proper statistical accuracy of the final simulation results. In DESC+ + this problem has been solved by automating analysis of simulation output data, aimed at stopping simulation when the estimates reach the required level of precision. The package consists of various object classes. While some of them are responsible for on-line output data analysis, others allow simulation programs of telecommunication networks to be easily developed by re-using existing (sub)models. We discuss main design and implementational issues of DESC+ +, and illustrate them by an example.  相似文献   
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Chemotactic factors which induce polymorphonuclear neutrophils (PMN) to migrate directionally and release granular enzyme constituents also induce these cells to aggregate. The potency of these factors in inducing aggregation closely parallels their chemotactic and enzyme-releasing potencies. Several reagents known to influence the migratory and degranulatory response of PMN to chemotactins have been examined for their influence on chemotactic factor-induced aggregation of PMN. We have found that ambient temperatures below 37 degrees C, deoxyglucose, and iodoacetic acid inhibit PMN aggregation, whereas sodium cyanide and dinitrophenol have no effect. Inhibitors of microtubules (colchicine and vinca alkaloids) and of protein synthesis (cyclohexamide) had no effect. Cytochalasin B markedly enhanced aggregation. We conclude that chemotactin-induced aggregation is similar to the other chemotactin-induced PMN functions in the requirements for proper temperature and intact glycolytic pathways; in contrast, however, and intact cytoskeletal microtubular system appears unessential for this response. This may be explained by assuming that the chemotactic factor-induced aggregation of PMN is predominantly a surface membrane-dependent phenomenon.  相似文献   
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