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31.
32.
Parastoo Jangouk Thomas Dehmel Gerd Meyer Zu Hörste Andreas Ludwig Helmar C. Lehmann Bernd C. Kieseier 《Glia》2009,57(16):1765-1774
The disintegrin and metalloproteinase 10 (ADAM10) is a membrane‐anchored metalloproteinase with both proteolytic and disintegrin characteristics. Here, we investigate the expression, regulation, and functional role of ADAM10 in axonal outgrowth and myelination of the peripheral nerve. Expression pattern analysis of 11 ADAM family members in co‐cultures of rat dorsal root ganglia (DRG) neurons and Schwann cells (SCs) demonstrated the most pronounced mRNA expression for ADAM10. In further studies, ADAM10 was found to be consistently upregulated in DRG‐SC co‐cultures before the induction of myelination. Neurons as well as SCs widely expressed ADAM10 at the protein level. In neurons, the expression of ADAM10 was exclusively limited to the axons before the induction of myelination. Inhibition of ADAM10 activity by the hydroxamate‐based inhibitors GI254023X and GW280264X resulted in a significant decrease in the mean axonal length. These data suggest that ADAM10 represents a prerequisite for myelination, although its activity is not required during the process of myelination itself as demonstrated by expression analysis of myelin protein zero (P0) and Sudan black staining. Hence, during the process of myelin formation, ADAM10 is highly upregulated and appears to be critically involved in axonal outgrowth that is a requirement for myelination in the peripheral nerve. © 2009 Wiley‐Liss, Inc. 相似文献
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A serotonin (5-HT)-mediated phosphoinositide hydrolysis response was characterized in fibroblasts cultured from rabbit choroid plexus. 5-HT elicited a maximum 8-fold increase in [3H]inositol-phosphate ([3H]IP) formation, while the partial agonists, (+)-lysergic acid diethylamide and (−)-1-(4-bromo-2,5-dimethyoxyphenyl)-2-aminopropane caused 2- and 5-fold increases, respectively. Mianserin, ketanserin, and spiperone were equipotent at blocking the 5-HT-mediated response. Thus, agonist and antagonist profiles indicate interactions with 5-HT2 receptors. 相似文献
35.
Kevin Gruffydd-Jones Sandra Hollinghurst Sabbi Ward Gordon Taylor 《The British journal of general practice》2005,55(521):918-923
BACKGROUND: There is a high non-attendance rate for traditional clinic-based routine asthma care in general practice. Alternative methods of providing routine asthma care need to be examined. AIM: To examine the cost and effectiveness of targeted routine asthma care in general practice using telephone triage, compared to usual clinic care. DESIGN OF STUDY: An open randomised controlled trial. SETTING: A single semi-rural practice in the southwest of England. METHOD: Adult patients with asthma were randomised to receive either their routine asthma care in the surgery or care by telephone triage. Asthma control parameters, health status and NHS resource utilisation were measured over the 12-month study period. RESULTS: One hundred and ninety-four patients were randomised and 35% per cent more patients (n = 84 versus n = 62) received more than one consultation in the telephone group. Asthma control as measured by the asthma control questionnaire (ACQ) was similar in the clinic and telephone groups: mean change in ACQ = -0.11 (95% CI = -0.32 to 0.11) versus -0.18 (95% CI = -0.38 to 0.02). Mean NHS costs were 210 pounds sterling per patient per year in the telephone group compared to 334 pounds sterling in the clinic group (P-value of bootstrapped difference = 0.071). CONCLUSION: Targeted routine asthma care by telephone triage of adult asthmatics can lead to more asthma patients being reviewed, at less cost per patient and without loss of asthma control compared to usual routine care in the surgery. 相似文献
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J A Gottridge B R Meyer N S Schwartz R S Lesser 《Archives of internal medicine》1989,149(7):1660-1662
To determine the value of chest roentgenograms in the management of asymptomatic persons with positive tuberculin skin test results, we undertook a retrospective review of all tests administered by our Employee Health Service, North Shore University Hospital, Manhasset, NY, between July 1, 1983 and November 1, 1987. Of 5200 tests, 247 results were positive. Two hundred twenty-one of these charts were reviewed for roentgenographic results and the presence of symptoms. All persons were asymptomatic. Chest roentgenograms revealed the following: normal, 188; unrelated abnormalities, 24; apical pleural thickening, 5; granulomas, 2; calcified hilar node, 1; and calcified node plus granuloma, 1. We noted no active tuberculosis, nor did the chest roentgenographic results influence recommendations for isoniazid prophylaxis. We conclude that chest roentgenograms are of value in 0% to 1.3% of asymptomatic people with positive tuberculin test results. A larger study should be undertaken to further define the usefulness of chest roentgenograms in this population. 相似文献
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39.
Brain serotonin transporter binding in non-depressed patients with Parkinson's disease 总被引:2,自引:0,他引:2
M. Guttman I. Boileau J. Warsh J. A. Saint-Cyr N. Ginovart T. McCluskey S. Houle A. Wilson E. Mundo P. Rusjan J. Meyer S. J. Kish 《European journal of neurology》2007,14(5):523-528
Early post-mortem data suggest that damage to brain serotonin neurones might play a role in some features (e.g., depression) of Parkinson's disease (PD). However, it is not known whether such damage is a typical characteristic of living patients with PD or whether the changes are regionally widespread. To address this question we measured, by positron emission tomography imaging, levels of the brain serotonin transporter (SERT), a marker for serotonin neurones, as inferred from binding of [11 C]-3-amino-4-(2-dimethylaminomethyl-phenylsulfanyl)-benzonitrile (DASB), a second generation SERT radioligand, in subcortical and cerebral cortical brain areas of clinically advanced non-depressed (confirmed by structured psychiatric interview) patients with PD. SERT binding levels in PD were lower than those in controls in all examined brain areas, with the changes statistically significant in orbitofrontal cortex (−22%), caudate (−30%), putamen (−26%), and midbrain (−29%). However, only a slight non-significant reduction (−7%) was observed in dorsolateral pre-frontal cortex, an area implicated in major depression. Our imaging data suggests that a modest, regionally widespread loss of brain serotonergic innervation might be a common feature of advanced PD. Further investigation will be required to establish whether SERT binding is more or less decreased in those patients with PD who also have major depressive disorder. 相似文献
40.
The craft of surgery has always relied on the use of instruments. Innovations in surgery have paralleled innovations in instrumentation.
Advances in surgical instrumentation continue today and have enabled huge strides in surgical procedures and outcomes during
this generation. Computers and related technology are now changing the interface between the surgeon and the patient, and
are poised to improve patient outcomes by enhancing the surgeon’s skills and training. The application of computer enhanced
telemanipulators, or “robots”, may specifically enhance operations, for example Heller myotomy, that require good visualization
and precise careful dissection of delicate structures. This review covers the pathophysiology of achalasia and its history
of medical and surgical treatment, leading to modern robotic telesurgical approaches. Improvements in outcome from medical
to standard surgical to robotic telesurgical approaches are discussed. Current operative technique for robotic telesurgical
treatment of achalasia is described and the authors conclude with a glimpse of where, in the future, current research endeavors
will lead us in the treatment of achalasia. 相似文献