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181.
Angiogenesis induction and regression in human surgical wounds 总被引:2,自引:0,他引:2
Nicola J. Brown PhD ; Edward A. E. Smyth Bmedsci ; Simon S. Cross MD ; Malcolm W. R. Reed MD 《Wound repair and regeneration》2002,10(4):245-251
Angiogenesis in human wound healing is not well characterized, with only sparse information available regarding the maturation and fate of vessels formed as a consequence of human tissue repair. Therefore, this study aimed to establish the temporal profile of angiogenesis in human dermal wounds. Punch biopsies were obtained under local anesthesia from 45 patients following breast surgery. Scars were predominantly between 2 and 52 weeks after surgery but in five patients were > 52 weeks. Control samples were taken from breast skin peroperatively (n = 24). Quantification of vascular density was performed using the Chalkley grid, following antibody staining for platelet endothelial cell adhesion molecule. Vascular patterns, wound cellularity and morphology were also determined. Cumulative microvessel density was increased in all samples when compared to controls (p < 0.05). This was greatest 2 to 24 weeks following surgery 17 (15-21) median (range), decreased thereafter, but remained elevated compared to controls even in the mature scars > 52 weeks. Control tissue showed an ordered morphological arrangement of dermal structures, collagen, and elastic fibers. However, wounding resulted in marked structural distortion for up to 15 weeks. In conclusion, this study shows for the first time the prolonged persistence of both microvessels and cellularity (fibroblastic cells), in addition to structural distortion in human dermal wounds, which is in contrast to previous in vitro and in vivo studies. 相似文献
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183.
Michael C. Dalsing MD Melissa Kevorkian BS Beth Raper BA Craig Nixon MS Stephen G. Lalka MD Dolores F. Cikrit MD Joseph L. Unthank PhD Malcolm B. Herring MD 《Annals of vascular surgery》1989,3(2):127-133
This study evaluates the potential for endothelial seeding of a collagen-impregnated Dacron graft with or without surface modifiers (fibronectin, heparin) to attach and retain these cells during flow. Human umbilical endothelial cells were harvested, cultured, labeled with Indium111-oxine and seeded onto 30 mm X 4 mm diameter grafts. Six graft surfaces were studied: 1) a collagen-impregnated Dacron graft, HemashieldR (C); 2) C + fibronectin (C + F); 3) C + heparin (C + H); 4) C + F + H; 5) HytrelR + F (Hyt + F); and 6) Hyt + F + H. Radioactive loss determined the percentage attachment and then percentage retention of labeled inoculum after a one-hour in vitro perfusion. Scanning electron and light microscopy demonstrated the endothelium on the graft surface following perfusion. Fibronectin-coated grafts had a significantly higher percentage attachment than those without fibronectin (ANOVA, P less than 0.05). However, the percentage retention following perfusion was similar for all Dacron grafts and statistically inferior to the HytrelR grafts studied (ANOVA, P less than 0.05). SEM evaluation of the C + F + H graft surface was qualitatively the most impressive Dacron surface for seeding, yet was inferior to the HytrelR graft. We conclude that fibronectin benefits the initial attachment of endothelium to collagen-coated Dacron rivaling the HytrelR surface. Fibronectin does not improve percentage retention of the HemashieldR surface during perfusion, therefore, some of its initial benefit is lost. 相似文献
184.
Infantile Digital Fibroma Treated With Mohs Micrographic Surgery 总被引:2,自引:0,他引:2
John G. Albertini MD Maj USAF MC Michael Jude Welsch MD CPT USA MC Leo A. Conger MD LTC USA MC Lester F. Libow MD COL USA MC Dirk M. Elston MD COL USA MC 《Dermatologic surgery》2002,28(10):959-961
BACKGROUND: Infantile digital fibroma (IDF) is a rare benign fibrous tumor of childhood that frequently recurs despite local excision. Conservative, nonsurgical management may result in regression and/or joint deformity. OBJECTIVE: To describe the histologic features of IDF and discuss a case excised using Mohs micrographic surgery (MMS). METHODS: Case report and review of the clinical, histologic, and ultrastructural features. RESULTS: Characteristic inclusion bodies of actin were identified with hematoxylin and eosin, Masson's trichrome, and rapid actin immunostain. The tumor was debulked and the majority was removed after one stage of MMS, except where the deep margin approached the joint space. The defect healed by secondary intention. At 2 years the patient had no recurrence or functional joint deformity. CONCLUSION: MMS is a surgical treatment option for IDF. 相似文献
185.
Kenneth K. H. Chao BS Eric Cheung BS William B. Armstrong MD Brian J. F. Wong MD 《Otolaryngology--head and neck surgery》2002,126(6):593
Objective: The study goal was to compare the laser spot size created using reflective and refractive micromanipulators with a CO2 laser and to determine the sensitivity of spot size to laser power. Study Design and Setting: A CO2 laser and operating microscope (400-mm focal length) was coupled to either a reflective (Cassegrain-like) or refractive micromanipulator. Laser spot size was determined by measuring the region of ablation created by laser irradiation of wood (dry tongue depressors), exposed photographic film, and agar gel using optical micrometry. Laser power varied from 0.5 to 20 W with pulse durations of 0.1 and 0.5 second. Results: The reflective micromanipulator demonstrated overall smaller spot sizes for a given laser power and lower incremental change in spot size with increasing power. The reflective design demonstrated less sensitivity to increases in laser power. Conclusions: Micromanipulator optical design can result in significant differences in laser spot size. The reflective device used in this study demonstrated less sensitivity to increasing laser power. (Otolaryngol Head Neck Surg 2002;126:593-597.) 相似文献
186.
187.
Elliot Carlisle MD Mario Luna MD Paul M. Tsou MD Jeffrey C. Wang MD 《The spine journal》2005,5(6):608-614
BACKGROUND CONTEXT: There is limited information describing the correlation between the initial quantitative measurements on magnetic resonance imaging (MRI) scans of disc herniation area, canal cross-section areas, percent canal compromise, and disc herniation location to the need for surgery. PURPOSE: Our aim is to determine if the size of disc herniation area, canal cross-section area, percent canal compromise, and disc herniation location taken from MRI images of patients with symptomatic single-level lumbar herniated intervertebral discs upon initial presentation to a spine surgeon, were predictive of the need for surgical treatment. STUDY DESIGN/SETTING: This is a retrospective case matched study of patient MRI images in the senior author's private practice. PATIENT SAMPLE: From a pool of 332 patients with sciatica caused by lumbar intervertebral disc herniations at our institution, 65 patients had surgery, of which MRI images were available and analyzed on 44 patients. Forty-four additional patients were randomly selected from the remaining 267 original group as nonoperative controls. METHODS: The axial MRI image showing the largest canal compromise by the herniated disc was selected for measurements. Using T1- and T2-weighted images, the areas of interest were digitally scanned at high resolution. The canal area and disc herniation area measurement were calculated from the total number of pixels per cross-sectional area, multiplied by a scan correction factor, mm(2) /pixel. Disc herniation locations were classified into either central or paracentral. The percent canal compromise was obtained by disc herniation area divided by canal cross-section area and multiplied by 100. RESULTS: The surgical group's overall mean herniated disc area was 219.6 square millimeter (mm(2)), 179.8 at L4-5, and 267.4 at L5-S1. The nonoperative group's overall mean herniated disc area was 178.4 mm(2), 135.1 at L2-3, 160.3 at L4-5, and 207.4 at L5-S1. The surgical group's overall mean canal cross-sectional area was 471.8 mm(2), 418.6 at L4-5, and 535.6 at L5-S1. The nonoperative group's overall mean canal cross-sectional area was 541.3 mm(2), 518.1 at L2-3, 446.8 at L4-5, and 669.9 at L5-S1. The overall percent canal compromise ratio in the surgery group was 46.7%, 44.1% at L4-5, and 49.8% at L5-S1. The overall percent canal compromise in the nonoperative group was 34.2%, 34.1% at L2-3, 36.1% at L4-5, and 31.8% at L5-S1. The percent canal compromise in central herniations at L4-5 level was 53.0% in the surgical group, and 32.8% in the nonoperative group; at the L5-S1 level surgical group percent canal compromise was 64.1% and in the nonoperative group canal compromise was 27%. L4-L5 level paracentral herniations canal compromise was 36.7% in the surgical group compared with 42.5% canal compromise in the nonoperative group. At the L5-S1 level the canal compromise was 45% in the surgical group and 34.8% in the nonoperative group. CONCLUSIONS: Our findings show a trend for patients treated with surgery to have larger disc herniation areas and smaller canal cross-section areas, corresponding to larger percent canal compromise than the nonoperative group. Centrally located herniations followed this trend closely at all levels studied. However, the paracentral herniation at the L4-5 level does not follow this trend, possibly because paracentral disc herniation clinical course is determined more by herniation location rather than the overall herniation size. 相似文献
188.
189.
Although lesions of the pterygopalatine space are uncommon, there are instances in which this relatively inaccessible region must be entered for biopsy or excision of masses. Traditional open approaches to the pterygopalatine space, involving external or intraoral incisions, provide limited visualization and carry associated morbidities. The evolution and advancement of endoscopic sinus surgical technique in recent years has led to its application to anatomic areas outside the strict limits of the sinonasal cavities. Such minimally invasive approaches are safe, effective, and spare unnecessary discomfort to the patient. This article describes the authors' method for performing an endoscopic approach to the pterygopalatine space. 相似文献
190.