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91.
Jennifer M. Lynch Erin M. Buckley Peter J. Schwab Ann L. McCarthy Madeline E. Winters David R. Busch Rui Xiao Donna A. Goff Susan C. Nicolson Lisa M. Montenegro Stephanie Fuller J. William Gaynor Thomas L. Spray Arjun G. Yodh Maryam Y. Naim Daniel J. Licht 《The Journal of thoracic and cardiovascular surgery》2014
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Mary K. McCarthy Donald C. Goff Lee Baer Jillian Cioffi David B. Herzog 《The International journal of eating disorders》1994,15(3):219-226
Histories of childhood trauma have been reported previously in bulimic subjects but no study to date has assessed how these experiences may affect response to fluoxetine. Thirty outpatient subjects in a placebo-controlled trial of 60 mg of fluoxetine for the treatment of bulimia nervosa completed the Dissociative Experiences Scale and a self-report instrument assessing trauma. Response to treatment was measured with the Hamilton Depression Scale-17 (HAMD-17), the CGI, the PGI, and the change in number of binges per day. Subjects taking fluoxetine with histories of physical abuse showed a significantly greater drop in HAMD-17 scores than those without such histories. No relationship between a reported history of abuse and the response of binging to fluoxetine was found. A history of abuse does not appear to predict the response of hinging to fluoxetine but may predict a greater response of nonspecific symptoms like depression. © 1994 by John Wiley & Sons, Inc. 相似文献
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Glial cells have a major role in protecting neurons against various forms of stress. Especially, astrocytes mediate the bulk of glutamate clearance in the brain via specific membrane transporters (GLAST and GLT1), thereby preventing the occurrence of excitotoxic events. Although glutamate-mediated mechanisms are thought to contribute to nigral dopaminergic neuron degeneration in Parkinson's disease, detailed information on the organization of glia in the substantia nigra is still lacking. The present study was performed to provide quantitative information on the organization of astroglia and on the relationships between astrocytes and excitatory synapses in the rat substantia nigra. Using immunolabeling of GLT1 and confocal imaging, we found that the substantia nigra was filled with a dense meshwork of immunoreactive astrocyte processes. Stereological analysis performed on electron microscope images revealed that the density of immunoreactive astrocyte plasma membranes was substantial, close to 1 μm2/μm3, in the substantia nigra neuropil, both in the pars compacta and the pars reticulata. Excitatory synapses had on average two thirds of their perimeters free from glia, a disposition that may favor transmitter spillover. The density of glutamatergic synapses, as quantified on confocal images by the simultaneous detection of bassoon and of vesicular glutamate transporter 1 or 2, was very low (0.01 and 0.025 per μm3 in the reticulata and compacta subdivisions, respectively). Thus the ratio of GLT1-expressing glial membrane surface to glutamatergic synapses was very high (40–100 μm2), suggesting an efficient regulation of extracellular glutamate concentrations. 相似文献
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Differences in reendothelialization after balloon catheter removal of endothelial cells, superficial endarterectomy, and deep endarterectomy 总被引:1,自引:0,他引:1
S G Goff H D Wu L R Sauvage Y Usui A R Wechezak D E Coan R E Arnell M W Walker 《Journal of vascular surgery》1988,7(1):119-129
The process of reendothelialization was studied in a deendothelialized 3 cm segment of the canine descending thoracic aorta from which peripheral endothelial cell ingrowth had been prevented by impervious prosthetic graft sleeves. Three preparations were studied: (1) removal of only the endothelial cells, accomplished by flow surface drying and balloon catheter denudation, (2) removal of the superficial portion of the nonvasal media, accomplished by endarterectomy to a depth of 200 to 300 micron, and (3) removal of the entire inner (nonvasal) media, accomplished by endarterectomy to a depth of 500 to 600 micron to reach the outer (vasal) media. A total of 44 specimens were studied after implantation periods of 7, 14, 28, and 56 days. In all cases endothelial cell ingrowth from the host aorta into the test specimen was prevented by the impervious graft sleeves. In the deep endarterectomy group there were scattered areas of reendothelialization at 1 week, extensive reendothelialization at 2 weeks, almost complete reendothelialization at 4 weeks, and confluence by 8 weeks. However, in the superficial endarterectomy group scanning electron microscopy showed scattered areas of factor VIII/von Willebrand factor (FVIII/vWF)-negative, endothelial-like cells at 4 weeks, whereas at 8 weeks most of the surface was covered by endothelial cells identified by FVIII/vWF. In those specimens subjected to balloon catheter removal of endothelial cells only, reendothelialization was not seen, even at 8 weeks. 相似文献
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G A Schultz M Zammit L R Sauvage M P Spencer T E Kowalsky S G Goff J C Smith 《Journal of vascular surgery》1987,5(3):475-478
Of 394 carotid endarterectomies performed during a 10-year period, 36 (9%) included Dacron patch graft angioplasties. Patch graft angioplasties were used selectively in patients because they had undergone previous carotid endarterectomy or had small-caliber vessels. There were no postoperative infections, occlusions, emboli, stroke, or pseudoaneurysms. In addition, no clinically detectable recurrent stenoses developed in this high-risk group of patients. Twenty-four of the 27 patients available for follow-up were screened for asymptomatic stenoses with spectral analysis and B-mode imaging; there was no sign of hemodynamically significant recurrent stenosis in this group. These encouraging results support the continued selective use of Dacron patch graft angioplasty in carotid surgery. 相似文献