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61.
In the months following transection of adult rat peripheral nerve some sensory neurons undergo apoptosis. Two weeks after sciatic nerve transection some neurons in the L4 and L5 dorsal root ganglia begin to show immunoreactivity for nestin, a filament protein expressed by neuronal precursors and immature neurons, which is stimulated by neurotrophin-3 (NT-3) administration. The aim of this study was to examine whether NT-3 administration could be compensating for decreased production of neurotrophins or their receptors after axotomy, and to determine the effect on nestin synthesis. The levels of mRNA in the ipsilateral and contralateral L4 and L5 dorsal root ganglia were analyzed using real-time polymerase chain reaction, 1 day, 1, 2 and 4 weeks after unilateral sciatic nerve transection and NT-3 or vehicle administration via s.c. micro-osmotic pumps. In situ hybridization was used to identify which cells and neurons expressed mRNAs of interest, and the expression of full-length trkC and p75NTR protein was investigated using immunohistochemistry. Systemic NT-3 treatment increased the expression of brain-derived neurotrophic factor, nestin, trkA, trkB and trkC mRNA in ipsilateral ganglia compared with vehicle-treated animals. Some satellite cells surrounding neurons expressed trkA and trkC mRNA and trkC immunoreactivity. NT-3 administration did not affect neurotrophin mRNA levels in the contralateral ganglia, but decreased the expression of trkA mRNA and increased the expression of trkB mRNA and p75NTR mRNA and protein. These data suggest that systemically administered NT-3 may counteract the decrease, or even increase, neurotrophin responsiveness in both ipsi- and contralateral ganglia after nerve injury. 相似文献
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Arruda VR; Pieneman WC; Reitsma PH; Deutz-Terlouw PP; Annichino-Bizzacchi JM; Briet E; Costa FF 《Blood》1995,86(8):3015-3020
The molecular characterization of the mutations in hemophilia A patients is hampered by the large size of the factor VIII gene and the great heterogeneity of mutations. In this study, we have performed a protocol involving multiplex polymerase chain reaction in which 19 exons were amplified in four different combinations followed by nonradioactive single-strand conformational polymorphism (SSCP) to screen for mutations. Southern blotting was used to detect inversion of the factor VIII gene resulting from recombination between copies of the gene A (F8A) located in intron 22 of the factor VIII gene and two copies close telomeric region of X chromosome. Forty-two hemophilia A patients (21 with severe and 21 with mild-to-moderate disease) were studied. The inversion of factor VIII occurred in 13 of 21 patients affected by severe hemophilia A. One patient showed a large extra band in addition to the three bands observed after Southern blotting with the F8A probe. An abnormal electrophoretic pattern of SSCP was detected in 85% and 50% of the patients affected by mild-to-moderate and severe disease, respectively. Sixteen different mutations were identified. Eleven mutations were novel and comprised 9 point mutations and 2 small deletions. This study shows that the methodology used is safe and rapid and has potential for detecting almost all of the genetic defects of the studied hemophilia A patients. 相似文献
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Shalender Bhasin MB BS Thomas G. Travison PhD Todd M. Manini PhD Sheena Patel MS Karol M. Pencina PhD Roger A. Fielding PhD Jay M. Magaziner PhD Anne B. Newman MD MPH Douglas P. Kiel MD Cyrus Cooper DM FMedSci Jack M. Guralnik MD PhD Jane A. Cauley Dr.PH Hidenori Arai MD PhD Brian C. Clark PhD Francesco Landi MD PhD Laura A. Schaap PhD Suzette L. Pereira PhD Daniel Rooks PhD Jean Woo MD PhD Linda J. Woodhouse PhD Ellen Binder MD Todd Brown MD Michelle Shardell PhD Quian-Li Xue PhD Ralph B. DʼAgostino Sr PhD Denise Orwig PhD Greg Gorsicki PhD Rosaly Correa-De-Araujo MD PhD Peggy M. Cawthon PhD 《Journal of the American Geriatrics Society》2020,68(7):1410-1418
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Amanda M Balkhi Adam M Reid Joseph PH McNamara Gary R Geffken 《Pediatric diabetes》2014,15(6):408-415
Online forums for chronic health conditions emerged as early as 30 yr ago and interest in their study has blossomed. Type 1 diabetes (T1D) forums have grown exponentially since 2005. Therefore, a comprehensive evaluation of these forums is needed. This study assesses the demographics and motivations of parents who use type 1 diabetes forums and the potential impact that forum membership (FM) has on parenting stress and hypoglycemic fear. One hundred and two parents were recruited through online T1D forums and asked to complete qualitative and quantitative measures of their experience with the T1D forums. Results of this study suggest that parents who use T1D forums mirror those who participate in clinic‐based research protocols and are primarily motivated to participate in forums to increase their diabetes knowledge and gain social support. Indeed, parents who use T1D forums report high levels of trust, social support, and perceived knowledge gained. However, FM was positively related to increased self‐reported parenting stress frequency and hypoglycemic fear behaviors. Taken together, the relationships formed within these communities may have a significant impact on the experience of these caregivers. The need for future research and potential implications for physicians, including parent debriefing, are discussed. 相似文献
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Alexander E White Andrew FW Ho Nur Shahidah Nurul Asyikin Le Xuan Liew Pin Pin Pek Jade PH Kua Michael YC Chia Yih Yng Ng Shalini Arulanandam Sieu-Hon Benjamin Leong Marcus EH Ong 《Singapore medical journal》2021,62(8):438
Care for patients who experience out-of-hospital cardiac arrest (OHCA) has rapidly evolved in the past decade. Increased sophistication of care in the community, emergency medical services (EMS) and hospital setting is associated with improved patient-centred outcomes. Notably, Utstein survival doubled from 11.6% to 23.1% between 2011 and 2016. These achievements involved collaboration between policymakers, clinicians and researchers, and were made possible by a strategic interplay of policy, research and implementation. We review the development and current state of OHCA in Singapore using primary population-based data from the Pan-Asian Resuscitation Outcomes Study and an unstructured search of research databases. We discuss the roles of important milestones in policy, community, dispatch, EMS and hospital interventions. Finally, we relate these interventions to relevant processes and outcomes, such as the relationship between the strategic implementation of bystander cardiopulmonary resuscitation and placement of automated external defibrillator with return of spontaneous circulation, survival to discharge and survival with favourable neurological outcomes. 相似文献
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PH Young 《Nurse education today》1987,7(6):285-288
Writing for publication is rewarding; it requires specific skills which are identified and explored in this article. Intending authors are encouraged to be systematic in targeting the audience, prepararing the text, and presenting it to a publisher. The differing styles needed for academic articles, book reviews and letters are explored as are the stages in publication. 相似文献
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