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991.
Background: Persons with basal cell skin cancer (BCSC) have shown increased risk of developing cancer at several other sites.
Methods: We identified 3164 persons with BCSC and 15,730 comparison subjects matched for age, sex, race, residence area and length of membership in a health maintenance organization.
Results: In retrospective follow-up for up to 24 years (mean 11.3 years), BCSC patients experienced statistically significant increases in the incidence of all cancer (relative risk [RR] = 1.2, 95% confidence interval [CI] = 1.1–1.4) lung cancer (RR = 1.4, CI = 1.0–1.8) and melanoma (RR = 2.2, CI = 1.6–3.0). Women experienced significantly increased risk for all cancer, lung cancer, melanoma and thyroid cancer, increases of borderline significance in breast cancer, non-Hodgkin's lymphoma and leukemia, and increased pre-existing bladder cancer. Men showed statistically significant increases in all cancer, melanoma, and kidney cancers, and mouth and throat cancers. Multivariate analysis incorporating available risk factor data did not weaken positive associations with BCSC except slightly for melanoma and for bladder cancer in women. Other previously reported associations were not confirmed.
Conclusion: Periodic skin examinations appear well justified after removal of BCSC to detect new skin cancers including melanoma. Given the relatively weak, unexplained associations of BCSC with internal cancers, the costs vs. benefits of extra efforts to detect the latter still need to be determined. 相似文献
992.
F. Mirrashed J. C. Sharp V. Krause J. Morgan B. Tomanek 《Skin research and technology》2004,10(3):161-168
BACKGROUND/AIMS: Puckered, dimply skin on the thighs, hips, and buttocks is known as cellulite. The cause of cellulite is not known, although there are a number of different hypotheses. In this study, we use magnetic resonance (MR) micro-imaging to study cellulite skin. To the best of our knowledge, this is the first reported MR study of cellulite. METHODS: High-resolution in vivo MR images of the postlateral thigh skin of two male groups and four female groups were obtained. Subjects were grouped according to their body mass index (BMI) and cellulite grade. A qualitative assessment of how MRI can be used to differentiate skin tissue at different levels of cellulite grading was performed. RESULTS: We found that changes in skin architecture with cellulite can be visualized by in vivo MR micro-imaging. The skin fat layers beneath the dermis and down to the level of muscles are well visualized in the images. Also, the diffuse pattern of extrusion of underlying adipose tissue into dermis is clearly imaged, and was found to correlate with cellulite grading. We also show that other skin tissue parameters such as (a) the percentile of adipose vs. connective tissue in a given volume of hypodermis and (b) the percentile of hypodermic invaginations inside the dermis are correlated with cellulite grade. CONCLUSION: MR images can be interpreted to measure tissue parameters correlated with cellulite. Considering that we had only three subjects in each group, the achievements of this pilot study were highly satisfactory. We have shown that the in vivo micro-MR is a technique able to detect the effects of cellulite and gender. This study can be extended for further investigations of drugs and/or medical devices for cellulite treatment. 相似文献
993.
F. G. Bechara T. Gambichler M. Stücker A. Orlikov S. Rotterdam P. Altmeyer K. Hoffmann 《Skin research and technology》2004,10(3):169-173
BACKGROUND: Optical coherence tomography (OCT) is a new and promising diagnostic technique for investigation of skin tumours. We describe a method that makes evaluation and definition of specific morphologic structures of skin tumours via OCT more accurate. MATERIALS AND METHOD: We investigated three patients with basal cell carcinoma and three patients with melanocytic nevi. Three-dimensional (3D) images were obtained from these skin tumours via OCT according to previously applied marks, which were tattooed with special histological marking dye after excision of the tumours. Corresponding to these marks, we investigated serial histological sections (haematoxylin&eosin staining). RESULTS: We could prove similar morphological structures both in OCT and histology. Due to tissue deformation, the compared measurements of structures like cell nests or epidermal thickness were slightly deviated. However, by this method we could prove similar tissue formations in OCT and histology. CONCLUSIONS: Due to the deformation by histological processing and slightly different sectioning levels, the comparison of histological pictures and OCT images seems difficult. Nevertheless, in two cases it was possible to demonstrate the same morphological structures with OCT imaging and histological investigation. Our method could play an important role for further evaluation of OCT images. We estimate better evaluation of OCT imaging using a 3D reconstruction method. 相似文献
994.
A. J. Schou K. Thomsen A. M. Plomgaard O. D. Wolthers 《Skin research and technology》2004,10(3):200-206
BACKGROUND: High-frequency ultrasound of the skin has recently been introduced for assessment of systemic effects in the cutis and subcutis of oral and inhaled glucocorticoids in children. However, the use of high-frequency skin ultrasound in clinical trials is invalidated because important methodological aspects have not been addressed. The aim of the present study was to evaluate inter- and intraobserver, day to day and diurnal variations of measurement of thickness of cutis and subcutis, and the fraction of low echogenic pixels (fLEP) in the cutis and, furthermore, to assess effects of exercise on the cutis and subcutis and variations in subcutaneous thickness between anatomical locations in children with a high-frequency B-mode ultrasound scanning device. METHODS: Three studies were conducted, each including 10 healthy prepubertal children. High-frequency skin ultrasound was performed with the 20 MHz Dermascan C (Cortex Technology, Hadsund, Denmark). In study 1, the same observer performed five consecutive scannings to assess intraobserver variations. In study two different observers performed scannings at 2 h intervals between 08:00 and 20:00 h, whereby interobserver and diurnal variations were assessed. In study 3, the same observer performed scannings in different anatomical locations on five consecutive days, and on one of these days before and after exercise. Thus day-to-day variations and the effect of exercise were assessed. RESULTS: Low inter- and intraobserver variations were found on assessment of the thickness of cutis and subcutis, whereas high variations were found on evaluation of the dermal water content. Diurnal variations were absent, and day-to-day variations were low. Exercise caused significant increases in the thickness of cutis and subcutis on the thigh. CONCLUSION: Low inter- and intraobserver variations make high-frequency ultrasound a precise and reliable tool for assessment of the cutaneous and subcutaneous thickness in children. In future trials, repetitive scannings need not to be performed at the same time of the day, whereas strenuous physical activity should be avoided on days of examination. 相似文献
995.
BACKGROUND: Asymptomatic skin sensitization (AS) has been shown to be a risk factor for respiratory allergic disease. OBJECTIVE: We investigated allergen and recall antigen-driven T cell proliferation, cytokine production and T cell expression of the chemokine receptor CCR4, in cultures derived from symptomatic atopics (SA), subjects with AS and healthy controls (HC). Numbers of allergen-specific precursor T cells in all three groups were also estimated. METHODS: Peripheral blood mononuclear cells from the three groups were isolated and stimulated with allergen and tetanus toxoid. Proliferation, cytokine production and CCR4 expression were measured by flow cytometry. RESULTS: A significantly increased proportion of CD4(+) memory T cells proliferated in response to allergen in SA as compared with subjects with AS (P<0.001) and HC (P<0.001). Only in SA was expansion of CD4(+)CCR4(+) T cells, after allergen stimulation observed. SA had higher frequencies of allergen-specific T cells than subjects with AS and HC (P=0.02, for both). With regard to allergen-induced production of T-helper type 1 (Th1) and Th2 cytokines, subjects with AS and HC resembled each other, while differing significantly from SA. CONCLUSION: We conclude, that subjects with AS, although clearly IgE sensitized, have significant diminished numbers of allergen-specific T cells as well as decreased allergen-induced CD4(+) memory T cell proliferation as compared with SA. To a large extent, our findings are capable of explaining the immunological characteristics associated with AS. Our findings may serve as better prognostic markers for subsequent allergic progression, than previously described clinical and paraclinical characteristics. 相似文献
996.
目的 总结成人阴茎段尿道缺损的于术修复方法及阴囊中缝区皮瓣的临床应用。方法 2000年1月~2005年11月,对不同原因的阴茎段尿道缺损患者26例,年龄18~40岁。应用局部阴茎皮瓣再造缺损尿道,其中先天性阴茎型尿道下裂16例;外伤性阴茎中段尿道缺损6例。远段尿道缺损4例。外伤1~4年,曾行尿道造瘘术,反复尿道外口开大。应用以阴囊前、后动脉为蒂的阴囊中隔岛状皮瓣进行刚茎腹侧再造尿道表面创面的覆盖,皮瓣范围在阴囊中缝区宽2.5cm,长5.5cm内。结果 术后除4例患者并发感染而漏尿,术后2~4周内自行愈合外,其余患者伤口均Ⅰ期愈合。术后随访7个月~4年,阴茎无弯曲,排尿无异常。结论 应用阴茎局部皮瓣再造尿道及阴囊中缝区带蒂岛状皮瓣覆盖创面,是修复青春期后阴茎段尿道缺损一种良好的方法,下术操作简便,皮瓣血运可靠,修复后阴茎外形及功能均良好。 相似文献
997.
Skin cancer is the most common cancer worldwide. Its incidence is doubling every 15–20 years likely because of an aging population,
changes in behaviour towards sun exposure, and increased UV light fluency at the earth surface due to ozone depletion. In
this review, we summarize the most important genetic changes contributing to the development of malignant melanoma, basal
cell carcinoma and squamous cell carcinoma, the main tumor entities arising in the skin. While our understanding of the oncogenes
and tumor suppressor genes involved in the development and progression of skin tumors is still fragmentary, recent advances
have shown alterations affecting conserved signalling pathways that control cellular proliferation and viability. These pathways
includeINK4a/Rb,ARF/p53, RAS/MAPKs, and sonic hedgehog/Gli.
Supported by an unrestricted educational grant by Bristol-Myers Squibb. 相似文献
998.
W Harth K Mayer R Linse 《Journal of the European Academy of Dermatology and Venereology》2004,18(4):503-507
The borderline syndrome is one of the most severe disturbances of psychosomatic dermatology. Patients with borderline syndrome are situated 'on the border' of psychosis, neurosis and personality disorders. The skin as a borderline organ carries a symbolic role. The clinical picture includes artefactual skin diseases due to self-mutilation by conscious or unconscious cutting, and rubbing, scratching or para-artefactual manipulations of pre-existing dermatoses. Leading symptoms of the borderline syndrome are poor impulse control, emotional instability and poor ego strength with low frustration tolerance and unstable personal relationships. We present the case of a 38-year-old female patient with borderline syndrome suffering from para-artefactual skin diseases of the face and a massive hyperhidrosis of the hands and feet. Within 9 months she was treated in four acute psychiatric hospitals and by 12 psychiatrists and psychotherapists. Early and accurate diagnosis and high-quality, sophisticated long-term therapy are necessary. 相似文献
999.
BACKGROUND/PURPOSE: Sagging of the face skin is a visible and unattractive characteristic of skin ageing. This phenomenon, due to both gravitational force and age-related alterations in the mechanical properties of skin, has never been quantitatively studied. The aim of this paper was, first, to define a method and a precise procedure allowing the objective measurement of this phenomenon and, second,to study how it is related to age. METHODS: We used an electronically controlled bed that allows the comparison of submental skin profiles in both the reclined and the upright positions. A parameter that characterises the sagging amplitude for an individual was defined and the reproducibility of measurement of this parameter was verified. RESULTS: Results, obtained from 66 female volunteers, demonstrated a statistically significant positive correlation between this new parameter and age, and also between this new parameter and the elastic recovery parameter of skin, as measured by torquemeter. CONCLUSION: Age-related changes of the skin's mechanical properties and of the various underlying skin tissues would explain this phenomenon. This new method and procedure should allow objective evaluation of the efficacy of any treatments (cosmetic, medical or surgical) proposed for rendering the appearance of people younger. 相似文献
1000.