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991.
The treatment of renal artery stenosis by angioplasty and stenting is an effective and accepted alternative to surgery for the treatment of renovascular hypertension and preservation of renal function. We report the technical and clinical outcomes of renal artery stenting in patients with a solitary functioning kidney and renal artery stenosis. From October 1993 to November 1999, 30 stents were placed in the renal arteries of 27 patients (mean age 72 ± 8 years) with a solitary functioning kidney and azotemia. The mean diameter renal artery stenosis was 86 ± 14%. The mean preprocedure serum creatinine (Cr) level was 3.0 ± 1.5 mg/dL (range 1.5–7.5 mg/dL), arterial blood pressure was 171 ± 29/85 ± 13 mmHg, and the number of antihypertensive drugs was 2.9 ± 1.1. Indications for stenting were suboptimal balloon dilation (n = 16), intimai dissection (n = 6), and restenosis following angioplasty (n = 5). Atherosclerotic ostial lesions were present in 25 (93%) of 27 renal arteries. This represents the largest series of renal artery stenting in patients with a solitary functioning kidney, and demonstrates this treatment modality to be a relatively safe alternative to conventional surgery in this high-risk patient group. Most (74%) of the patients in this series had improved or stabilized renal function. Further efforts to define preprocedural indicators of success are necessary to identify the patients who may benefit from revascularization of their solitary kidney. Presented at the Twenty-fifth Annual Meeting of the Peripheral Vascular Surgery Society, Toronto, Ontario, Canada, June 10, 2000.  相似文献   
992.
BACKGROUND: Eruptive syringomas are uncommon benign adnexal neoplasms. They are numerous and disseminated and often have a predilection for the neck, face, chest, and axillary fossae. Because they are persistent, usually numerous, and often on exposed sites, the lesions may be disfiguring and often pose significant cosmetic concerns for patients. Many treatment modalities such as dermabrasion, electrodesiccation with curettage, and scissors excision have been tried with some success, but more recently lasers have provided good to excellent results. OBJECTIVE: To describe an approach to the treatment of eruptive syringomas in an African American patient with a combination of trichloroacetic acid (TCA) and CO2 laser resurfacing, providing acceptable cosmetic results without significant side effects. METHODS: We describe an African American patient with eruptive syringomas of the face treated with a combination of TCA and CO2 laser resurfacing with good results. RESULTS: While the syringomas were not completely ablated, the combination of TCA and CO2 laser resurfacing provided acceptable cosmetic results without significant side effects. CONCLUSION: The TCA pretreatment probably removed some of the bulk of the surface of the lesions, thereby reducing the number of laser passes required to flatten the remainder of the lesions and thus lessening the potential for thermal damage at the treated sites and of surrounding normal skin.  相似文献   
993.
Healing of diabetic wounds still remains a critical medical problem. Polydeoxyribonucleotide (PDRN), a compound having a mixture of deoxyribonucleotide polymers, stimulates the A2 purinergic receptor with no toxic or adverse effect. We studied the effects of PDRN in diabetes‐related healing defect using an incisional skin‐wound model produced on the back of female diabetic mice (db+/db+) and their normal littermates (db+/+m). Animals were treated daily for 12 days with PDRN (8 mg/kg/ip) or its vehicle (100 μL 0.9%NaCl). Mice were killed 3, 6, and 12 days after skin injury to measure vascular endothelial growth factor (VEGF) mRNA expression and protein synthesis, to assay angiogenesis and tissue remodeling through histological evaluation, and to study CD31, Angiopoietin‐1 and Transglutaminase‐II. Furthermore, we measured wound breaking strength at day 12. PDRN injection in diabetic mice resulted in an increased VEGF message (vehicle=1.0±0.2 n‐fold vs. β‐actin; PDRN=1.5±0.09 n‐fold vs. β‐actin) and protein wound content on day 6 (vehicle=0.3±0.07 pg/wound; PDRN=0.9±0.1 pg/wound). PDRN injection improved the impaired wound healing and increased the wound‐breaking strength in diabetic mice. PDRN also caused a marked increase in CD31 immunostaining and induced Transglutaminase‐II and Angiopoietin‐1 expression. Furthermore, the concomitant administration of 3,7‐dimethyl‐1‐propargilxanthine, a selective adenosine A2A receptor antagonist, abolished PDRN positive effects on healing. However, 3,7‐dimethyl‐1‐propargilxanthine alone did not affect wound healing in both diabetic mice and normal littermates. These results suggest that PDRN might be useful in wound disorders associated with diabetes.  相似文献   
994.
Skin wound healing in Yorkshire pigs closely approximates human wound healing. Conversely, red Duroc pigs form fibroproliferative, hypercontractile scars. As mast cells have been implicated in several fibrotic conditions, the present study used these models to evaluate the potential role of mast cells in wound contraction and fibrosis. Immediately following the creation of full‐thickness excisional wounds, the mast cell stabilizer ketotifen was used to treat both Yorkshire and red Durocs. Control red Durocs showed significantly more wound contraction than Yorkshires, both before and after reepithelialization. Ketotifen treatment significantly reduced the first phase of contraction in red Duroc wounds to a level equivalent to Yorkshire wounds, but had no detectable effect on the postepithelialization phase of contraction. Cessation of drug treatment after 10 weeks did not lead to resumption of excessive contraction in red Durocs, indicating that ketotifen blocked rather than delayed such contraction during a critical phase of healing. Ketotifen treatment also reduced the deposition of collagen within the red Duroc wounds, but did not affect Yorkshire wound contraction or collagen deposition. These results suggest that ketotifen may be an effective treatment for the reduction of excessive wound contraction and fibrosis in human cutaneous injuries, without affecting the normal healing process.  相似文献   
995.
The use of hyperbaric oxygen therapy to treat chronic wounds: A review   总被引:3,自引:0,他引:3  
Chronic wounds, defined as those wounds which fail to proceed through an orderly process to produce anatomic and functional integrity, are a significant socioeconomic problem. A wound may fail to heal for a variety of reasons including the use of corticosteroids, formation of squamous cell carcinoma, persistent infection, unrelieved pressure, and underlying hypoxia within the wound bed. Hypoxia appears to inhibit the wound healing process by blocking fibroblast proliferation, collagen production, and capillary angiogenesis and to increase the risk of infection. Hyperbaric oxygen therapy (HBOT) has been shown to aid the healing of ulcerated wounds and demonstrated to reduce the risk of amputation in diabetic patients. However, the causal reasons for the response of the underlying biological processes of wound repair to HBOT, such as the up‐regulation of angiogenesis and collagen synthesis are unclear and, consequently, current protocols remain empirical. Here we review chronic wound healing and the use of hyperbaric oxygen as an adjunctive treatment for nonhealing wounds. Databases including PubMed, ScienceDirect, Blackwell Synergy, and The Cochrane Library were searched for relevant phrases including HBOT, HBO/HBOT, wound healing, and chronic/nonhealing wounds/ulcers.  相似文献   
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Background Tumor markers whose antigenic determinants have been demonstrated to consist of carbohydrates are probably one of the most extensive tools that have been used in routine cancer diagnosis. In this study, the relevance of carbohydrate antigen expression profile was examined in esophageal squamous cell carcinoma together with prognosis in 130 patients. Methods The expression of carbohydrate antigens was estimated immunohistochemically by anti–sialyl Lewis a (sialyl Lea) and anti–sialyl Lewis x (sialyl Lex) monoclonal antibodies, and correlation between their staining and clinicopathological status was examined. In addition, the correlation of both carbohydrate antigens expression was evaluated with microvessel density (MVD). Results Expressions of sialyl Lewis antigens and MVD were associated with several clinicopathological features that reflect the tumor aggressiveness in esophageal cancer. The 5-year survival rate of patients was found to be associated with expression of sialyl Lea and sialyl Lex antigens and with MVD; thus, all of them were revealed to be independent prognostic factors. Conclusions Combination of these factors offered a better prediction of prognosis of esophageal squamous cell carcinoma. Further, carbohydrate antigens represent a promising target for therapeutic approaches against the disease.  相似文献   
1000.
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