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R Ingemarson  H Lankinen 《Virology》1987,156(2):417-422
We have isolated two monospecific monoclonal mouse antibodies directed against the HSV-1 ribonucleotide reductase. When immobilized to Sepharose, both antibodies remove enzyme activity from solution. However, on immunoblots of crude extracts of HSV-1-infected cells, one antibody only detects a 140K protein and the other antibody only a 40K protein. Neither antibody recognizes the cellular ribonucleotide reductase or the related pseudorabies virus-induced enzyme. Therefore, our data strongly suggest that the HSV-1 ribonucleotide reductase consists of a 140K and a 40K protein. The 140K protein is sequentially degraded to 110K, 93K, and 81K proteins by a Vero cell-specific, N alpha-p-tosyl-L-lysine chloromethyl ketone-sensitive protease. Of the different proteolytic products, at least the 93K species seems to be enzymatically active, suggesting that part of the 140K protein may have functions not related to ribonucleotide reduction. There is a very high affinity between the 140K and 40K proteins as evident from affinity chromatography on antibody-Sepharose and sedimentation velocity centrifugation in a glycerol gradient. The 140K and 40K proteins cosediment with the HSV-1 ribonucleotide reductase activity at 17 S. This indicates that the active form of the HSV-1 reductase consists of the 140K and 40K proteins forming a tight complex of the alpha 2 beta 2 type.  相似文献   
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Purpose: The aim of this study was to investigate the ability of n-alkenyl succinic anhydrides (n-ASAs) to improve the film-forming characteristics of a novel coating polymer, potato starch acetate degree of substitution 2.8 (SA). n-ASAs were also applied to improve the otherwise brittle properties of ethyl cellulose (EC) aqueous dispersion (Aquacoat®) and EC solvent-based films. Methods: The effectiveness of two n-ASAs, 2-octenyl succinic anhydride (OSA) and 2-dodecen-1-ylsuccinic anhydride were evaluated as plasticizers. Mechanical properties, both water vapor and drug permeabilities, and glass transition temperatures of the cast free films were measured. Triethyl citrate and dibutyl sebacate were used as reference plasticizers. Results: The long hydrocarbon chain of n-ASA, with its accessible carbonyl groups, enabled a strong plasticization effect on the tested polymers. Due to the excellent mechanical properties (i.e., a tough film structure with considerable flexibility) and low permeability of the plasticized films, n-ASAs, and especially OSA proved to be an ideal plasticizer particularly for EC based coatings. Also, the EC aqueous dispersion plasticized with n-ASAs resulted in a markedly enhanced coalescence of the colloidal polymer particles, even at low drying temperatures. Conclusions: In applications where a coating with high flexibility is required, n-ASAs can be used as plasticizers at moderately high concentrations (up to 60–70%, w/w) without losing the high tensile strength, excellent toughness and low permeability of EC and SA films.  相似文献   
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We study the performance of stochastic local search algorithms for random instances of the K-satisfiability (K-SAT) problem. We present a stochastic local search algorithm, ChainSAT, which moves in the energy landscape of a problem instance by never going upwards in energy. ChainSAT is a focused algorithm in the sense that it focuses on variables occurring in unsatisfied clauses. We show by extensive numerical investigations that ChainSAT and other focused algorithms solve large K-SAT instances almost surely in linear time, up to high clause-to-variable ratios alpha; for example, for K = 4 we observe linear-time performance well beyond the recently postulated clustering and condensation transitions in the solution space. The performance of ChainSAT is a surprise given that by design the algorithm gets trapped into the first local energy minimum it encounters, yet no such minima are encountered. We also study the geometry of the solution space as accessed by stochastic local search algorithms.  相似文献   
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Objectives. Carbonic anhydrase IX (CA IX) expression is induced by local hypoxia. We studied whether CA IX deposits associate with ascending aortic dilatation. Design. Aortic wall histology, CA IX expression, presence of leukocytes, plasma cells, macrophages, endothelial cells, smooth muscle cells, cell proliferation, elastin and collagen were studied in histological specimens collected from 30 patients who underwent surgery for ascending aorta. The samples were grouped according to presence of CA IX deposits. Results. Twenty out of 30 patients had CA IX-positive deposits within the adventitia, whereas 10 specimens remained negative. Adventitial inflammation was increased in CA IX-positive samples as compared with CA IX-negative ones (p?<?0.01). The mean diameter of the ascending aorta at the sinotubular junction increased significantly in patients with CA IX-positive staining as compared with CA IX-negative cases (63?±?3 vs 53?±?2?mm, p?<?0.02). Receiver operating characteristic curve analysis confirmed the association of CA IX positivity with increased ascending aortic dilatation (AUC 0.766; S.E. 0.090; p?=?0.020; 95% C.I. 0.590–0.941). Conclusions. Positive CA IX staining in certain aortic specimens suggests that increased CA activity may contribute to ascending aortic dilatation.  相似文献   
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OBJECTIVE: To evaluate a newly developed education programme for Parkinson's disease (PD) patients. METHODS: The programme consisted of eight sessions and aimed at improving knowledge and skills related to self-monitoring, health promotion, stress management, depression, anxiety, social competence, and social support, all with special reference to PD. The programme was formatively evaluated in seven European countries (Spain, Finland, Italy, The Netherlands, United Kingdom, Estonia, Germany) with 151 patients diagnosed with idiopathic PD. The evaluation included patients' ratings of the comprehensibility and feasibility of the programme as well as mood ratings before and after each session. Patients also completed questionnaires at the beginning and end of the programme to explore possible changes in disease-related psychosocial problems, quality of life, and depression. RESULTS: The programme was feasible to run, and patients were able to understand its elements. Patients reported mood elevations following individual sessions and reduced disease-related psychosocial problems after completing the programme. There were no substantial differences in results between cultures. CONCLUSION: Patient education appears to have potential as a useful and feasible intervention, complementing medical treatment in PD. PRACTICE IMPLICATIONS: The present programme will soon be available in seven European languages and can be tested in different health care systems.  相似文献   
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The objective was to identify dental professionals' attitudes and awareness on evidence based dentistry (EBD), and to elucidate perceived barriers and views on how to move towards EBD. A questionnaire was sent to 290 dental professionals (dental hygienists, general dentists, specialist dentists) in the county of Halland, Sweden. The questionnaire consisted of closed questions and free text sections, related to attitudes, awareness and skills on databases, EBD, and terms related to scientific publications, as well as perceived barriers towards EBD. A majority of the respondents had a welcoming attitude towards EBD. The respondents perceived their colleagues less positive towards EBD. The respondents considered EBD, at least partly, useful in daily dental practice. With the exception of general dentists in private practice, a vast majority of the dental professionals thought that EBD would improve the care of their patients. Dental professionals in the county of Halland, in Sweden, had a welcoming attitude towards EBD, and indicated an open attitude for learning more about interpretation of evidence from scientific publications. The most commonly perceived barriers towards EBD, were 'lack of time' and 'poor availability of evidence'.  相似文献   
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Aseptic loosening of hip replacements is driven by the macrophage reaction to wear particles. The extent of particle‐induced macrophage activation is dependent on the state of macrophage polarization, which is dictated by the local cytokine microenvironment. The aim of the study was to characterize cytokine microenvironment surrounding failed, loose hip replacements with an emphasis on identification of cytokines that regulate macrophage polarization. Using qRT‐PCR, the expression of interferon gamma (IFN‐γ), interleukin‐4 (IL‐4), granulocyte–macrophage colony‐stimulating factor (GM‐CSF), IL‐13, and IL‐17A was low and similar to the expression in control synovial tissues of patients undergoing primary hip replacement. Using immunostaining, no definite source of IFN‐γ or IL‐4 could be identified. IL‐17A positive cells, identified as mast cells by double staining, were detected but their number was significantly reduced in interface tissues compared to the controls. Significant up‐regulation of IL‐10, M‐CSF, IL‐8, CCL2‐4, CXCL9‐10, CCL22, TRAP, cathepsin K, and down regulation of OPG was seen in the interface tissues, while expression of TNF‐α, IL‐1β, and CD206 were similar between the conditions. It is concluded that at the time of the revision surgery the peri‐implant macrophage phenotype has both M1 and M2 characteristics and that the phenotype is regulated by other local and systemic factors than traditional macrophage polarizing cytokines. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 32:1241–1246, 2014.  相似文献   
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