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991.
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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993.
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   
994.
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   
995.
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997.
BACKGROUND: Botulinum toxin type A (BTX-A) injections are overwhelmingly safe and effective treatment in cosmetic treatment, but some patients are apprehensive about pain associated with injection. OBJECTIVE: To determine whether preprocedural application of lidocaine 4% topical anesthetic cream to the injection site will reduce pain on injection of BTX-A for the treatment of crow's feet. METHODS: Twenty-four participants receiving bilateral injections for crow's feet were enrolled. Subjects were randomized to one of four study groups. Prior to BTX-A injection, group 1 (n = 6) received lidocaine 4% cream on the right side of the face and vehicle cream on the left side of the face; group 2 (n = 6) received vehicle cream on the right side and lidocaine 4% on the left side; group 3 (n = 6) received lidocaine 4% on both sides; and group 4 (n = 6) received vehicle cream on both sides. RESULTS: We observed a statistically significant reduction in subject-reported procedural pain in participants pretreated with lidocaine 4% on both sides of the face compared with controls. CONCLUSION: Lidocaine 4% cream is effective in reducing the pain associated with BTX-A injection for crow's feet. We encourage further study to clarify the optimal use of topical anesthetics in the practice of cosmetic dermatology.  相似文献   
998.
Background Results from in vitro and animal studies suggest that cyclooxygenase (COX) inhibitors may reduce the risk of melanoma, but among humans, the evidence remains limited.
Objective In a pilot retrospective cohort, to determine the relationship between the use of COX inhibitors and the incidence, recurrence, and metastases of melanoma in high-risk patients.
Methods Reviewing computerized records at the Miami Veterans Affairs Medical Center, we retrospectively examined the association between COX inhibitor use and melanoma incidence, recurrence, and metastases in high-risk subjects: white subjects previously diagnosed with melanoma (1996–2003). We evaluated three potential outcomes: new melanoma diagnosis, recurrence of a previous melanoma, and melanoma metastasis.
Results Eighty-three subjects with melanoma were included. There was one metastasis among 28 subjects prescribed COX inhibitors, whereas four new melanomas (7.3%), two melanoma recurrences, and six metastases (10.9%) occurred among 55 patients not prescribed COX inhibitors. Although no individual outcomes measures reached statistical significance, combining the three measures, these were significantly lower in users of COX inhibitors compared with nonusers (1 vs 12;  p = .05  ). After adjustment for age and tumor depth of invasion, COX inhibitor users had significantly lower rates of melanoma outcome measures (odds ratio 0.08; 95% confidence interval 0.01–0.77;  p = .03  ).
Conclusion Potential exists for chemoprevention of melanoma among high-risk patients.  相似文献   
999.
Background. This article addresses the use of liquid injectable silicone as both an immediate and long-lasting treatment for broad-based, depressed acne scars. The only filler substance that maintains precision and permanence in improving and/or correcting these types of acne scar defects is medical-grade liquid silicone.
Objective. We describe five patients with a history of acne scarring who showed improvements from injections of liquid silicone at the initial treatment session and lasting over a 10-, 15-, and 30-year follow-up period.
Methods. Monthly liquid silicone injections using a technique known as the microdroplet, multiple-injection approach.
Results. This article documents the safety, effectiveness, and precision of silicone in addition to highlighting the fact that its permanence is what distinguishes it from other filler materials.
Conclusion. As a precise and permanent filling substance used for soft tissue augmentation, liquid injectable silicone can improve and/or eliminate depressed, broad-based acne scars through a technique known as the microdroplet, multiple-injection approach.  相似文献   
1000.
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