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761.
Wound healing in the adult is commonly compromised by excessive scar formation. In contrast, fetal wound healing is a regenerative process characterised by the conspicuous absence of scarring. Available evidence suggests that phenotypic differences between fetal and adult fibroblasts are important determinants of these distinct modes of tissue repair. In this context, a number of groups (including our own) have documented differences between fetal and adult fibroblasts with respect to such potentially relevant characteristics as migratory activity, motogenic response to cytokines and the synthesis of motility factors, cytokines and matrix macromolecules. The oral mucosa appears to be a privileged site in the adult in that it continues to display a fetal-like mode of wound healing. Data are presented in this review indicating that a subpopulation of gingival fibroblasts expresses several 'fetal-like' phenotypic characteristics. These observations are discussed in terms of both the continued expression of a fetal-like mode of wound healing in the oral mucosa and the possible differential involvement of distinct fibroblast subpopulations in the progression of periodontal disease.  相似文献   
762.
Topical retinoids are been used to successfully treat acne for almost 3 decades. At the beginning, a retinoid was a compound of similar structure and action to retinol (vitamin A).(1) Changes at the carboxylic end group, the polyene chain, and the aromatic ring can result in the modification of the original molecule. To date, three generations of retinoids have been developed: the nonaromatics (retinol, tretinoin, and isotretinoin), the monoaromatics (etretinate and acitretin), and the polyaromatics (arotinoid, adapalene, and tazarotene). The new synthetic retinoid molecules have little resemblance with retinol but nonetheless are included in this family because they have the ability to bind with or activate retinoid receptors. Therefore, retinoids are vitamins and also hormones.(3)  相似文献   
763.
764.
765.
Disease dissemination is the major cause of melanoma-related death. A crucial step in the metastatic process is the intravascular invasion and circulation of melanoma cells in the bloodstream with subsequent development of distant micrometastases that is initially clinically undetectable and will eventually progress into clinically apparent metastasis. Therefore, the use of molecular methods to detect circulating melanoma cells may be of value in risk stratification and clinical management of such patients. Herein, we review the currently applied techniques for the detection, isolation, enrichment and further characterization of circulating melanoma cells from peripheral blood samples in melanoma patients. Furthermore, we provide a brief overview of the various molecular markers currently being evaluated as prognostic indicators of melanoma progression.  相似文献   
766.
慢性无临床症状的炎症与2型糖尿病的发生有关,流行病学资料认为这种关联在妇女表现得更为强烈。虽然小型临床研究显示短期口服大剂量阿司匹林具有明显的降糖效果,但是并没有随机试验直接评估临床可接受的剂量的阿司匹林预防糖尿病的效果。在美国一项随机、双盲、安慰剂-对照的女性健康研究(Women's Health Study)中,38716名45岁以上的且无临床糖尿病的健康女性随机口服小剂量的阿司匹林(n=19326)或安慰剂(n=19390),  相似文献   
767.
Objectives This study aimed to characterize the spectrum of skin diseases affecting children in Greece. Methods We retrospectively studied data for 4071 children, aged 0–12 years, who were examined and diagnosed with dermatoses at the outpatient clinic of a university dermatological hospital between December 2005 and August 2007. To evaluate changes in disease patterns, these data were compared with data for a cohort of 12,700 children diagnosed with skin diseases at the same clinic two to three decades earlier (in 1977, 1980, and 1983). Results The most frequent disease was dermatitis/eczema (34.7%), with atopic dermatitis found in 20.7% of children, contact dermatitis in 6.9%, pityriasis alba in 2.1%, and seborrheic dermatitis in 1.8%. Infections (19.3%), nevi (5.6%), scabies (4.8%), and insect bites (4.3%) followed. More viral (12%) than bacterial (3.7%) and fungal (3.6%) infections were noted. Warts constituted 53.2% of viral infections. Immigrants had an increased risk for bacterial infections and scabies. Conclusions Children diagnosed with skin diseases 24–30 years earlier were younger; exhibited lower prevalences of dermatitis/eczema (P = 0.01), viral infections (P < 0.001) and nevi (P < 0.001); higher prevalences of bacterial and fungal infections (P < 0.001) and insect bites (P < 0.01); and similar rates of scabies (P = 0.17). This study documents the high prevalence of atopic dermatitis in the region, the increasing incidence of viral infections and nevi, and the continuing problem of scabies, especially in immigrants.  相似文献   
768.
Flutrimazole is an imidazole derivative that has been proven to be efficient in superficial skin fungal infections. The aim of this randomised double-blind study was to compare for the first time, the efficiency and safety of flutrimazole 1% shampoo versus ketoconazole 2% shampoo in the treatment of tinea versicolor. Study population consisted of 60 patients with pityriasis versicolor diagnosed clinically and through direct microscopy and culture. Patients were randomly assigned to two groups: one instructed to apply flutrimazole shampoo 1% and one instructed to apply ketoconazole shampoo 2% both on head and body for 14 days. Patients were re-evaluated 14 days after the end of treatment clinically and through direct microscopy and culture. Twenty-one of 26 patients (80.8%) in the ketoconazole and 22 of 29 patients (75.9%) in the flutrimazole group had both visual healing and negative mycological evaluation. Comparison of the response between the two groups with the Yates' corrected chi-square was found statistically not significant (chi(2) = 0.19, d.f. = 1, P = 0.91). None of the patients in the two groups reported any adverse effects. Fourteen (53%) patients in the ketoconazole group and 23 (79%) in the flutrimazole group assessed the shampoos as cosmetically acceptable regarding texture, smell and foam properties. Flutrimazole shampoo 1% appears to present efficacy comparable with ketoconazole 2% in the treatment of tinea versicolor.  相似文献   
769.
Schuening  FG; Storb  R; Stead  RB; Goehle  S; Nash  R; Miller  AD 《Blood》1989,74(1):152-155
Amphotropic helper-free retroviral vectors containing either the bacterial neomycin phosphotransferase gene (NEO) or a mutant dihydrofolate reductase gene (DHFR*) were used to infect canine hematopoietic progenitor cells. In previous experiments, successful transfer and expression of both genes in canine CFU-GM were achieved after 24-hour cocultivation with virus-producing cells. The average rate of gene expression was 10% (6% to 16%) as measured by the number of CFU-GM resistant to either the aminoglycoside G418 or methotrexate. In an attempt to increase the efficiency of gene transfer, marrow was cocultured for 24 hours with either NEO or DHFR* virus-producing packaging cells and then kept in long-term marrow culture fed three times with virus-containing supernatant (2 to 5 x 10(6) CFU/mL). After six days, cells were harvested and cultured in CFU-GM assay with and without a selective agent. The average rate of gene expression in CFU- GM in five independent experiments was 46% and ranged from 19% to 87%. In conclusion, the efficiency of gene transfer into canine hematopoietic progenitor cells has been increased fourfold by combining cocultivation with long-term marrow culture as compared with results obtained with cocultivation only.  相似文献   
770.
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