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991.
992.
María Luz Montesinos Manuel Castellano-Muoz Pablo García-Junco-Clemente Rafael Fernndez-Chacn 《Brain Research Reviews》2005,49(2):416-428
In neurons, a network of endocytic proteins accomplishes highly regulated processes such as synaptic vesicle cycling and the timely internalization of intracellular signaling molecules. In this review, we discuss recent advances on molecular networks created through interactions between proteins bearing the Eps15 homology (EH) domain and partner proteins containing the Asn–Pro–Phe (NPF) motif, which participate in important aspects of neuronal function as the synaptic vesicle cycle, the internalization of nerve growth factor (NGF), the determination of neuronal cell fate, the development of synapses and the trafficking of postsynaptic receptors. We discuss novel functional findings on the role of intersectin and synaptojanin and then we focus on the features of an emerging family of EH domain proteins termed EHDs (EH domain proteins), which are important for endocytic recycling of membrane proteins. 相似文献
993.
994.
S Ponce G Orive R M Hernández A R Gascón J M Canals M T Mu?oz J L Pedraz 《Journal of controlled release》2006,116(1):28-34
Alginates are the most employed biomaterials for cell encapsulation due to their abundance, easy gelling properties and apparent biocompatibility. However, as natural polymers different impurities including endotoxins, proteins and polyphenols can be found in their composition. Several purification protocols as well as different batteries of assays to prove the biocompatibility of the alginates in vitro have been recently developed. However, little is known about how the use of alginates with different purity grade may affect the host immune response after their implantation in vivo. The present paper investigates the long-term functionality and biocompatibility of murine erythropoietin (EPO) secreting C2C12 cells entrapped in microcapsules elaborated with alginates with different properties (purity, composition and viscosity). Results showed that independently of the alginate type employed, the animals presented elevated hematocrit levels until day 130, remaining at values between 70-87%. However, histological analysis of the explanted devices showed higher overgrowth around non-biomedical grade alginate microcapsules which could be directly related with higher impurity content of this type of alginate. Although EPO delivery may be limited by the formation of a fibrotic layer around non-biomedical grade alginate microcapsules, the high EPO secretion of the encapsulated cells together with the pharmacodynamic behaviour and the angiogenic and immune-modulatory properties of EPO result in no direct correlation between the biocompatibility of the alginate and the therapeutic response obtained. 相似文献
995.
There exists a constant need for a dental curing light that works reliably and conveniently in the general practitioner's office and can be used effectively for all the different curing procedures. Due to the need for improved physical properties of resin based composites (RBCs) and less stress at the marginal interface, light curing units (LCUs) experienced significant advances in the past years. The dental industry has focused on reducing the curing time by developing higher intensity curing lights and by altering the resin composition and photo-initiator concentration. As a result the dentist can now choose from a vast variety of curing lights, light intensities and curing methods. This article presents a review of the advances in light curing units and curing techniques, as well as the scientific principles that guided past developments and that will influence future advances. 相似文献
996.
Luis Chávez de Paz Gunnel Svens?ter Gunnar Dahlén Gunnar Bergenholtz 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2005,100(2):232-241
OBJECTIVES: The object of this study was to investigate the diversity among streptococcal species isolated from root canals in conjunction with endodontic therapy and to characterize their production of extracellular proteins. STUDY DESIGN: Consecutive root canal samples (RCS) taken as bacteriological controls during root canal treatment of teeth with apical periodontitis were analyzed in a total of 100 clinical cases. Bacteria were isolated and classified by selective media and gas liquid chromatography. Streptococcal strains were identified by carbohydrate fermentation, hydrolysis of aesculin/arginine, and production of enzymes. Releases of extracellular proteins by streptococci and Enterococcus spp in fluid culture media were examined with SDS-PAGE and 2-dimension gel electrophoresis (2 DE). Extracellular proteins produced were quantified and qualitatively analyzed. Specific proteins were targeted with Western immunoblot assays. Comparisons were made with type strains. RESULTS: Of a total of 241 bacterial strains recovered in the first samples submitted, Streptococcus gordonii, S anginosus, and S oralis were the most frequently isolated streptococci. In 49 of 89 resubmitted samples showing bacterial growth, S gordonii and S oralis still predominated among streptococci. Other common bacterial isolates were Enterococcus spp, Lactobacillus paracasei, and Olsenella uli. Quantitative and qualitative differences in extracellular protein production were observed among clinical isolates and laboratory streptococcal strains. In similar conditions for growth, S intermedius, S anginosus, S oralis, and S gordonii were strong producers of extracellular proteins (>3.0 microg/mL), while Enterococcus spp and S mutans were weak. Whole cell protein extracts showed a different profile from that of extracellular proteins. The chaperone protein DnaK was recognized to be produced extracellularly by S gordonii, S oralis, S anginosus, and S parasanguis. CONCLUSIONS: Being strong producers of extracellular proteins and by virtue of common presence in teeth undergoing endodontic therapy, S gordonii, S anginosus, and S oralis may be of pathogenic significance in posttreatment apical periodontitis. 相似文献
997.
Tod B Sloan Celia I Kaye William R Allen Brian E Magness Steven A Wartman 《Academic medicine》2005,80(11):994-1004
Changes in the education, research, and health care environments have had a major impact on the way in which medical schools fulfill their missions, and mission-based management approaches have been suggested to link the financial information of mission costs and revenues with measures of mission activity and productivity. The authors describe a simpler system, termed Mission-Aligned Planning (MAP), and its development and implementation, during fiscal years 2002 and 2003, at the School of Medicine at the University of Texas Health Science Center at San Antonio, Texas. The MAP system merges financial measures and activity measures to allow a broad understanding of the mission activities, to facilitate strategic planning at the school and departmental levels. During the two fiscal years mentioned above, faculty of the school of medicine reported their annual hours spent in the four missions of teaching, research, clinical care, and administration and service in a survey designed by the faculty. A financial profit or loss in each mission was determined for each department by allocation of all departmental expenses and revenues to each mission. Faculty expenses (and related expenses) were allocated to the missions based on the percentage of faculty effort in each mission. This information was correlated with objective measures of mission activities. The assessment of activity allowed a better understanding of the real costs of mission activities by linking salary costs, assumed to be related to faculty time, to the missions. This was a basis for strategic planning and for allocation of institutional resources. 相似文献
998.
999.
1000.
F. M. González Valverde F. Mauri Barberá M. Molto Aguado N. Torregrosa A. Hernández Quiles F. Menárguez Pina M. J. Gómez Ramos M. García Real J. A. Barreras Mateos J. L. Vázquez Rojas 《European Surgery》2004,36(4):253-256
Summary BACKGROUND: Endometriosis is a relatively common pathology in women of childbearing age and of low parity but rarely shows
extraperitoneal involvement. The main aim of this paper is to raise the attention of specialists to the necessity of carrying
out penetrating diagnosis of nonspecific extraperitoneal masses occurring in women of reproductive age. METHODS: We performed
a retrospective review of six patients diagnosed with extraperitoneal endometriosis who were treated at the Vega Baja University
Hospital (Spain) during the last 5 years. RESULTS: Surgical treatment had positive results in five patients. The preoperative
diagnosis was correctly made in only two patients. The accurate aetiology of endometriosis remains unknown and diagnosis is
based on clinical and cytopathological findings. CONCLUSIONS: Surgical treatment of extraperitoneal endometriosis is recommended.
However, postoperative follow-up is obligatory and hormonal suppressive therapy may be necessary. Medical treatment with gestagens,
Danazol, or agonists of the gonadotropin-releasing hormone are ineffective in endometriomas which are bigger than 2 cm.
相似文献