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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.
Early to mid-term fetuses heal cutaneous incisional wounds without scars; however, fetal response to burn injury has not been ascertained. We present a fetal model of thermal injury and subsequent analysis of fetal and lamb response to burn injury. A reproducible deep dermal burn injury was created in the fetus by application of water at 66 degrees C for 7 seconds, and at 82 degrees C for 10 seconds to the lamb. Macroscopically, the area of fetal scald was undetectable from day 7 post injury, while all lamb scalds were readily identified and eventually healed with scarring. Using a five-point histopathology scoring system for alteration in tissue morphology, differences were detected between control and scalded skin at all stages in lamb postburn, but no difference was detected in the fetal model after day 7. There were also large differences in content of alpha-smooth muscle actin and transforming growth factor-beta1 between control and scalded lamb and these differences were statistically significant at day 14 (P < 0.01). This novel model of fetal and lamb response to deep dermal injury indicates that the fetus heals a deep burn injury in a scarless fashion. Further elucidation of this specific fetal process of burn injury repair may lead to improved outcome for patients with burn injury.  相似文献   
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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   
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999.
BACKGROUND: Patients with varicose veins seek medical assistance for many reasons, including esthetic ones. The development of suitable and more flexible instruments, along with less invasive techniques, enables the establishment of new therapeutic procedures. OBJECTIVE: To compare endovenous great saphenous vein photocoagulation with an 810 nm diode laser and the conventional stripping operation in the same patient. METHODS: Twenty patients selected for operative treatment of primary great saphenous vein insufficiency on duplex scanning were assigned to a bilateral random comparison. In all cases, both techniques were performed, one on each lower limb. Clinically, evaluation was assessed on the seventh, thirtieth, and sixtieth postoperative days. Patients underwent examination with duplex ultrasonography and air plethysmography during the follow-up. RESULTS: Patients who received endovenous photocoagulation presented with the same pain but fewer swellings and less bruising than the stripping side. Most patients indicated that the limb operated on by laser received more benefits than the other. There was only one recanalization and no adverse effects. The venous filling time showed better hemodynamics in both techniques. CONCLUSION: The endovenous great saphenous vein photocoagulation is safe and well tolerated and presents results comparable to those of conventional stripping.  相似文献   
1000.
We determined the origin of new cartilage and new bone induced by recombinant human bone morphogenetic protein-2 (rhBMP-2) at the site of cricoid cartilage defects in rabbits randomly divided into eight groups. The cricoid cartilage was split vertically along the anterior midline and a strip was excised from the anterior part of the cricoid cartilage in all rabbits. The perichondrium from the anterior part of the cricoid cartilage was trimmed off in four groups; two groups treated with rhBMP-2 and two control groups. In four other groups, the anterior perichondrium was detached and used as a flap with two groups treated with rhBMP-2 and two groups serving as controls. The rabbits were killed 1 week or 4 weeks after surgery. The larynges were removed, fixed and sectioned, and the sections were stained for light microscopy using various cytochemical and immunological techniques. New cartilage was only present close to the host perichondrium adherent to cricoid cartilage in rabbits treated with rhBMP-2. New bone was present 4 weeks after surgery, although calcified matrix and alkaline phosphatase activity could be detected at the site of cricoid defects as early as 1 week after surgery. The cell proliferation marker Ki-67 was strongly expressed in granulation tissue and bone marrow, and it was moderately expressed in muscles adjacent to the cricoid cartilage in rhBMP-2-treated specimens. BMP receptors were strongly expressed in cartilage and moderately expressed in adjacent muscles. We conclude that new cartilage originates from the mesenchymal progenitor cells of host perichondrium adherent to cricoid cartilage in rabbits treated with rhBMP-2. New bone may originate from local muscle.  相似文献   
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