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61.
We investigated whether regenerating mature axons recapitulate embryonic features essential to successful reconnectivity within the injured nervous system. Strips from embryonic and adult chick retinae were cultured, and outgrowing axons were examined morphometrically and immunohistochemically. In addition, the target-recognition properties of adult neurites were analyzed. Regenerating adult axons elongate on a poly-L-lysine/laminin substratum with a speed about one order of magnitude slower than that of embryonic axons. Morphologically, adult axonal tips differ dramatically from embryonic growth cones in that they possess only filopodial extensions whereas embryonic growth cones possess both lamellipodial and filopodial processes. Both embryonic and adult neurites express the growth-associated protein GAP-43. When cultured on alternating stripes of anterior and posterior embryonic tectal membranes, both adult and embryonic retinal axons distinguish between the two membrane preparations. Our results demonstrate that during axonal regeneration the mature neurons express embryonic properties that are involved in the recognition of tectal positional cues.  相似文献   
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Emphysematous pyelonephritis is a severe life-threatening infection which continues to carry significant morbidity and mortality. We present a case recently managed at our institution by laparoscopic nephrectomy. The patient survived, and in comparison to some of the more conventionally managed patients in the literature, made an extremely speedy recovery. We would advocate this option to be seriously considered when patients are suitable and appropriately trained surgeons are available.  相似文献   
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Definitive treatment of extended thoracic aortic dilatation is a major surgical challenge. Histopathology of resected thoracic aortic wall may reveal undiagnosed aortitis affecting outcome. We sought to investigate the benefit of thorough histopathology after one-stage corrective surgery for the treatment of extended thoracic aortic dilatation. Five patients underwent one-stage corrective surgery using the hybrid open arch repair by the frozen elephant trunk together with endovascular aortic grafting. A representative sample of the resected aortic arch was procured for histology. T- and B-lymphocytes, plasma cells, macrophages, and immunoglobulin G4 (IgG4) positivity were evaluated by immunohistochemistry. The mean preoperative maximum aortic diameter was 54 mm (range, 41–79 mm). The mean follow-up was 18 months (range, 1–24 months). As confirmed by computed tomography (CT) upon follow-up, complete thrombosis of the false lumen at the level of the frozen elephant trunk was achieved in all patients with dissection. One patient was operated due to atherosclerotic dilatation of the thoracic aorta, and postoperative CT showed successful exclusion of the atherosclerotic dilatation; this 75-year-old man was diagnosed with IgG4-positive aortitis and experienced unexpected blindness after surgery without evidence of emboli or long-term neurological impairment upon repeated brain CT. The hybrid open arch repair by the frozen elephant trunk and simultaneous endovascular repair is a feasible choice for one-stage surgery through sternotomy aiming at definitive treatment of extended thoracic aortic pathology. However, systematic evaluation of inflammation may reveal concealed aortitis affecting postoperative outcome and need for long-term surveillance.  相似文献   
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Purpose Restorative proctocolectomy is the procedure of choice for patients undergoing proctocolectomy for familial adenomatous polyposis or ulcerative colitis. This meta-analysis was designed to identify differences in adverse events and functional outcomes between these two groups. Methods Studies published between 1986 and 2003 that compared outcomes between patients with familial adenomatous polyposis and ulcerative colitis were included. Meta-analytical techniques using random effect models were used to compare short-term and long-term adverse events as well as functional outcomes between the groups. Results Nineteen studies comprising 5,199 patients (familial adenomatous polyposis, 782; ulcerative colitis, 4,417) were analyzed. There were no significant differences in immediate postoperative adverse events between the two groups. Pouch-related fistulation was significantly increased in the ulcerative colitis group (10.5 percent vs. familial adenomatous polyposis 4.8 percent; odds ratio 2.31; P < 0.001). There was no significant difference in pouch failure between the two groups (ulcerative colitis 5.8 percent vs. familial adenomatous polyposis 4.5 percent; odds ratio 1.22; P = 0.43). The incidence of pouchitis was significantly greater in the ulcerative colitis group (30.1 vs. 5.5 percent; odds ratio 6.44; P < 0.001). Patients with familial adenomatous polyposis had a significant advantage in stool frequency with one less motion per 24 hours (95 percent confidence interval, 0.21–1.76; P = 0.01). Conclusions In contrast to studies reporting similar outcomes for patients undergoing restorative proctocolectomy for familial adenomatous polyposis or ulcerative colitis, the present meta-analysis suggested that patients with ulcerative colitis are at greater risk of pouch-related fistulation and pouchitis. Although there was an increase in the 24-hour stool frequency in the ulcerative colitis group, this may be accounted for by the younger age at surgery in the familial adenomatous polyposis group. Henry S. Tilney is sponsored by a research grant from The Royal College of Surgeons of England. Read at the meeting of the Association of Surgeons of Great Britain and Ireland, Edinburgh, Scotland, May 3 to 5, 2006.  相似文献   
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