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R. Steven Singer  MD 《Headache》2004,44(6):626-626
  相似文献   
994.
The prevention of new blood vessel growth is an increasingly attractive strategy to limit tumor growth. However, it remains unclear whether anti-angiogenesis approaches will impair wound healing, a process thought to be angiogenesis dependent. Results of previous studies differ as to whether angiogenesis inhibitors delay wound healing. We evaluated whether endostatin at tumor-inhibiting doses delayed excisional wound closure. C57/BL6J mice were treated with endostatin or phosphate-buffered solution 3 days prior to the creation of two full-thickness wounds on the dorsum. Endostatin was administered daily until wound closure was complete. A third group received endostatin, but also had daily topical vascular endothelial growth factor applied locally to the wound. Wound area was measured daily and the wounds were analyzed for granulation tissue formation, epithelial gap, and wound vascularity. Endostatin-treated mice showed a significant delay in wound healing. Granulation tissue formation and wound vascularity were significantly decreased, but reepithelialization was not effected. Topical vascular endothelial growth factor application to wounds in endostatin-treated mice resulted in increased granulation tissue formation, increased wound vascularity, and wound closure approaching that of control mice. This study shows that the angiogenesis inhibitor endostatin delays wound healing and that topical vascular endothelial growth factor is effective in counteracting this effect.  相似文献   
995.
Background. For several years, magnification has been used to separate follicular groupings from donor strips to minimize transection of hair follicles. There has been no discussion regarding the use of magnification to create recipient sites to limit transection of existing hair follicles in recipient zones.
Objective. The study was performed to evaluate the role of magnification when creating hundreds or thousands of recipient sites in patients with existing hair.
Methods. A 2× magnified polarized light-emitting diode (LED) for graft and recipient site creation (Syris Scientific, Gray, Maine) was used in 75 consecutive male and female patients. A team of four experienced surgical assistants and the author evaluated the device for graft creation, recipient site creation, and insertion of grafts.
Results. There was no perceived advantage in creating grafts or placing grafts compared with other magnification devices and traditional methods. There was less eye strain and greater ease in creating recipient sites using polarized magnification compared with traditional surgical lights and no magnification.
Conclusion. In an era of medications that slow or stop hair loss, magnification in recipient sites can reduce transection of existing hair follicles in recipient zones, leading to maximum density from a procedure. Further studies are needed to confirm the reduced transection rate of hair follicles and determine the ideal magnification. The use of magnification with LED polarized light in the recipient zone is an important new tool in hair transplant.  相似文献   
996.
BACKGROUND: The results from four phase III, randomized, vehicle-controlled studies showed that imiquimod 5% cream (imiquimod) was safe and effective in the treatment of actinic keratosis (AK). Patients applied imiquimod or vehicle cream to AK lesions on the face or balding scalp, dosing three times per week or two times per week for 16 weeks. OBJECTIVE: To obtain long-term safety follow-up data and estimate AK recurrence in patients who completely cleared their AK lesions in the treatment area at the 8-week post-treatment visit in the phase III studies. METHODS: One hundred forty-six patients from 30 study centers in the United States were evaluated for clinical evidence of AK, and safety data were collected. RESULTS: After a median follow-up period of 16 months, 24.7% (19 of 77) of the patients administered imiquimod three times per week and 42.6% (23 of 54) of the patients administered imiquimod two times per week had a recurrence of AK (the appearance of at least one AK lesion) in the original treatment area. The median number of AK lesions present was one lesion for both patients receiving imiquimod three times and those receiving imiquimod two times per week compared with a median of six lesions at baseline in the combined three times per week and two times per week phase III studies. There were no long-term safety issues, and the skin quality seen in the imiquimod-treated patients at the end of the phase III studies was maintained. CONCLUSION: One and a half years following treatment, imiquimod continued to provide a long-term clinical benefit in a majority of patients who experienced complete clearance of their AK lesions.  相似文献   
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Endogenous Growth Factors as Cosmeceuticals   总被引:1,自引:0,他引:1  
Background. Research into the pathophysiology of photodamaged skin has revealed correlations with certain aspects of acute and chronic wound healing. In wound healing, growth factors accumulate at the wound site and interact synergistically to initiate and coordinate wound healing.
Objectives. To review the effects of topical growth factors in wound healing and their potential use in treating photodamaged skin.
Methods. A mixture of multiple growth factors derived from human fibroblasts was applied topically to 14 patients twice daily for 60 days to stimulate the remodeling phase of wound healing.
Results. A total of 78.6% of patients with photodamaged skin showed clinical improvement at 60 days. New collagen formation increased by 37%, and epidermal thickening increased by 27%.
Conclusions. These data, as well as other studies of growth factors in wound healing, demonstrate positive cosmetic and clinical outcomes of topical application of growth factors for the treatment of photodamaged skin.
DR. FITZPATRICK IS THE FOUNDER OF SKIN MEDICA AND OWNS STOCK AS WELL AS STOCK OPTIONS.  相似文献   
999.
BACKGROUND: Twenty subjects were treated with either polidocanol (POL) or sodium tetradecyl sulfate (STS) to compare the efficacy and adverse sequelae of each agent. OBJECTIVE: To determine the safety and efficacy of two widely used sclerosing agents. METHODS: After the exclusion of saphenofemoral junction incompetency, each subject's leg veins were categorized by size (< 1, 1-3, and 3-6 mm in diameter). Each leg was then randomized to be treated with 0.5%, 1%, or 1% foam of POL or 0.25%, 0.5%, or 0.5% foam of STS according to vein size. An independent panel of four physicians, blinded to treatment, performed randomized photographic evaluations obtained pretreatment and 12 weeks post-treatment. Subject satisfaction index and overall clinical improvement assessment were also obtained. RESULTS: An average 83% improvement was noted for all vein sizes in all subjects with both POL and STS after a single treatment. Subjects were satisfied with treatment, regardless of the sclerosing agent used or the vein size treated. There was no statistically significant difference in adverse effects between each group. CONCLUSION: Both POL and STS are safe and effective sclerosing agents in the treatment of varicose and telangiectatic leg veins. Both are very tolerable and demonstrate similar post-treatment sequelae.  相似文献   
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