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991.
C. Oprea P.J. Szalanski M.V. Gustova I.A. Oprea V. Buzguta 《Applied radiation and isotopes》2009,67(12):2142-2145
R-mode factor analysis was applied to characterize the chemical composition of human teeth investigated by particle induced X-ray emission (PIXE), Rutherford backscattering spectrometry (RBS) and X-ray fluorescence (XRF) techniques. The approach developed in this study enabled the separation between essential mineral teeth components and the pollutants deposited in teeth tissues during the human life. The three independent sources of metals incorporated in human teeth were found. The first source, representing about 43% of the variance of the concentration data, was characterized by pollutant elements of power industry emissions. The second factor was loaded with toxic elements of general urban pollution. The third factor represented the tooth source as it contained mainly large fractions of the mineral components of the tooth tissue as Ca and K. 相似文献
992.
993.
994.
E. González-Guerra M. R. Haro M. C. Fariña L. Martín L. Manzarbeitia L. Requena 《Clinical and experimental dermatology》2009,34(7):800-803
Glomeruloid haemangioma is considered a specific marker of POEMS ( p olyneuropathy, o rganomegaly, e ndocrinopathy, M -protein and s kin changes) syndrome and it is usually but not always associated with multicentric Castleman's disease. We report a 78-year-old man who presented with a single, red-violet soft nodule with superficial telangiectases on the scalp. Histopathologically, the lesion consisted of lobules of coiled aggregated capillaries that involved the lumina of dilated vascular structures, mimicking renal glomeruli. A collagenous stroma separated the capillary lobules, and eosinophilic, periodic-acid–Schiff positive globules of varying sizes and shapes were seen within the cytoplasm of endothelial cells. Immunohistochemical studies with antibodies against IgA and IgG, and against the kappa and lambda light chains of immunoglobulins showed immunoreactivity within the eosinophilic globules. Results of complete blood count, liver, renal and thyroid function tests, fasting blood sugar measurement, serum levels of oestradiol, testosterone, prolactin and cortisol, serum protein electrophoresis, immunoelectrophoresis and immunofixation yielded normal or negative results. No Bence–Jones proteinuria was found in a sample from a 24-h urine collection. To our knowledge, only two cases of glomeruloid haemangioma have been previously reported in patients without POEMS syndrome. We describe the third case of glomeruloid haemangioma in a patient without features of POEMS syndrome. 相似文献
995.
L.J. Mackintosh† M.N.C. de Koning‡ W.G.V. Quint‡ J. ter Schegget‡ I.M. Morgan R.M. Herd† M.S. Campo 《The British journal of dermatology》2009,161(1):56-62
Background Nonmelanoma skin cancer (NMSC) has been linked to cutaneous human papillomaviruses of the genus beta (betaPV).
Objectives We sought to assess the presence of betaPV in NMSC biopsies from a group of Scottish skin cancer patients, both immunocompetent (IC) patients and immunosuppressed (IS) organ transplant recipients.
Methods One hundred and twenty-one paraffin-embedded skin tumours (27 actinic keratosis, 41 intraepidermal carcinoma, 53 squamous cell carcinoma) and 11 normal skin samples were analysed for the presence of betaPV by a polymerase chain reaction–reverse hybridization assay designed to detect the presence of the 25 known betaPV genotypes.
Results In IC patients, betaPV was detected in 30 of 59 (51%) tumours and two of 11 (18%) normal skin samples ( P = 0·046). In IS patients, betaPV was found in 27 of 62 (44%) tumours; no normal skin samples were available for comparison. The most frequently found genotypes were HPV-24, HPV-15 and HPV-38. Of those tumours infected with betaPV, 28 of 57 (49%) were infected with more than one genotype (range 2–8). Tumours from IS patients were from a younger age group (mean age 57·4 years) than IC patients (mean age 73·8 years). Multiple infections were more common in tumours from IC patients (21 of 30; 70%) compared with those from IS patients (seven of 27; 26%) ( P < 0·001). In the IC group, age did not appear to influence the distribution of single and multiple infections whereas in IS patients the proportion of multiple infections to single infections increased with age. There were no multiple infections in normal skin.
Conclusions A wide spectrum of betaPV types was detected in our samples. Further characterization of betaPV in vivo is needed in order to determine the mechanisms by which the virus contributes to cutaneous carcinogenesis. 相似文献
Objectives We sought to assess the presence of betaPV in NMSC biopsies from a group of Scottish skin cancer patients, both immunocompetent (IC) patients and immunosuppressed (IS) organ transplant recipients.
Methods One hundred and twenty-one paraffin-embedded skin tumours (27 actinic keratosis, 41 intraepidermal carcinoma, 53 squamous cell carcinoma) and 11 normal skin samples were analysed for the presence of betaPV by a polymerase chain reaction–reverse hybridization assay designed to detect the presence of the 25 known betaPV genotypes.
Results In IC patients, betaPV was detected in 30 of 59 (51%) tumours and two of 11 (18%) normal skin samples ( P = 0·046). In IS patients, betaPV was found in 27 of 62 (44%) tumours; no normal skin samples were available for comparison. The most frequently found genotypes were HPV-24, HPV-15 and HPV-38. Of those tumours infected with betaPV, 28 of 57 (49%) were infected with more than one genotype (range 2–8). Tumours from IS patients were from a younger age group (mean age 57·4 years) than IC patients (mean age 73·8 years). Multiple infections were more common in tumours from IC patients (21 of 30; 70%) compared with those from IS patients (seven of 27; 26%) ( P < 0·001). In the IC group, age did not appear to influence the distribution of single and multiple infections whereas in IS patients the proportion of multiple infections to single infections increased with age. There were no multiple infections in normal skin.
Conclusions A wide spectrum of betaPV types was detected in our samples. Further characterization of betaPV in vivo is needed in order to determine the mechanisms by which the virus contributes to cutaneous carcinogenesis. 相似文献
996.
Eric Racine Marie-Josée Dion Christine A. C. Wijman Judy Illes Maarten G. Lansberg 《Neurocritical care》2009,11(3):345-352
Background
Advances in intensive care medicine have increased survival rates of patients with critical neurological conditions. The focus of prognostication for such patients is therefore shifting from predicting chances of survival to meaningful neurological recovery. This study assessed the variability in long-term outcome predictions among physicians and aimed to identify factors that may account for this variability. 相似文献997.
998.
A. Perez S. E. Clements E. Benton A. Robson B. Bhogal C. M. Stefanato D. McGibbon 《Clinical and experimental dermatology》2009,34(8):e931-e933
We report a case of localized bullous pemphigoid (BP) in a woman patient with primary lymphoedema tarda. There is only one previous case reported of localized pemphigoid in an area of lymphoedema, this being of the cicatricial variant. Slow circulation in the lymphatic vessels, increased capillary permeability with preferential localization of antibodies in the area, and potential cleavage of the epidermal junction due to increased hydrostatic pressure leading to autoimmunity, have all been advocated as possible pathogenic mechanisms. Nevertheless, we consider that the mechanism by which localized pemphigoid arises on lymphoedema remains elusive, based on a previous case of generalized BP sparing an area of postsurgical lymphoedema. 相似文献
999.
Background: The term 'pigmented epithelioid melanocytoma (PEM)' was recently used for borderline melanocytic tumor/low-grade melanoma including cases previously diagnosed as human animal-type melanoma and epithelioid blue nevus. No Japanese cases have been reported.
Methods: We reviewed 219 cases previously diagnosed as blue nevus in Japan. Common blue nevus was identified in 154 cases and cellular blue nevus in 65 cases.
Results: We have found two Japanese cases of PEM previously diagnosed as cellular blue nevus. Two patients were female. The age at presentation was 32 and 28 years. Two lesions were on the buttock. Two cases fulfilled histological criteria proposed for PEM. There is no evidence of recurrence or metastases.
Conclusions: PEM is a distinct melanocytic tumor and the unifying diagnostic term. PEM is present in Japanese, but these cases may be previously diagnosed as cellular blue nevus. Japanese pathologists should recognize a new concept of PEM, and when they make a diagnosis of PEM, they should be recommended sentinel lymph node sampling. 相似文献
Methods: We reviewed 219 cases previously diagnosed as blue nevus in Japan. Common blue nevus was identified in 154 cases and cellular blue nevus in 65 cases.
Results: We have found two Japanese cases of PEM previously diagnosed as cellular blue nevus. Two patients were female. The age at presentation was 32 and 28 years. Two lesions were on the buttock. Two cases fulfilled histological criteria proposed for PEM. There is no evidence of recurrence or metastases.
Conclusions: PEM is a distinct melanocytic tumor and the unifying diagnostic term. PEM is present in Japanese, but these cases may be previously diagnosed as cellular blue nevus. Japanese pathologists should recognize a new concept of PEM, and when they make a diagnosis of PEM, they should be recommended sentinel lymph node sampling. 相似文献
1000.
J.P. Thyssen P. Jensen B.C. Carlsen K. Engkilde T. Menné J.D. Johansen 《The British journal of dermatology》2009,161(6):1288-1293
Background Chromium allergy has traditionally been caused by occupational skin contact with cement. In 1983, Danish legislation made the addition of ferrous sulphate compulsory in cement to reduce the water‐soluble chromium content to not more than 2 ppm. An effect from this intervention has previously been demonstrated among Danish construction workers. Objectives To investigate the development of chromium allergy among patients with dermatitis tested between 1985 and 2007 in Denmark. Furthermore, to determine causative exposures in patients with chromium allergy. Patients and methods A retrospective analysis of patch test data was performed (n = 16 228) and charts from patients with chromium allergy were reviewed. Comparisons were made using a χ2 test. Logistic regression analyses were used to test for associations. Results The prevalence of chromium allergy decreased significantly from 3·6% in 1985 to 1% in 1995 (Ptrend < 0·001) but increased to 3·3% in 2007 (Ptrend < 0·001). The frequency of clinically relevant cement exposure decreased significantly among patients with chromium allergy from 12·7% in 1989–1994 to 3·0% (P < 0·01) in 1995–2007, whereas the frequency of relevant leather exposure increased significantly from 24·1% during 1989–1994 to 45·5% during 1995–2007 (P < 0·02). Conclusions Chromium allergy is currently increasing in Denmark due to leather exposure. 相似文献