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71.
72.
T Fikrle K Pizinger 《Journal of the European Academy of Dermatology and Venereology》2007,21(1):48-55
BACKGROUND: Digital computer analysis of dermatoscopical images has been reported to facilitate the differential diagnosis of pigmented skin lesions in recent years. OBJECTIVE: The aim of our study was to perform digital computer analysis of a set of different melanocytic lesions and compare the objective results. METHODS: The set of 260 melanocytic lesions (150 excised difficult cases (46 melanomas, 47 atypical nevi, 57 common nevi and 110 unexcised common nevi) was automatically analysed by the digital dermatoscopical system microDERM. We searched for differences in asymmetry, size, compactness and colour distribution. Perimeter/area ratio was calculated. RESULTS: The perimeter/area ratio was detected as the most important criterion for differentiation between malignant and benign melanocytic lesions (sensitivity 91.3% and specificity 90.7% for malignant melanomas vs. all benign nevi; sensitivity 91.3% and specificity 80.8% for melanomas vs. clinically atypical nevi). Differences in size of the lesion, shape and asymmetry of colour were found and statistically verified. Using step-wise logistic regression the formula for calculation of probability of malignant nature of every analysed lesion was constructed. CONCLUSION: The perimeter/area ratio is a simple parameter for the differential diagnosis of melanocytic skin lesions. 相似文献
73.
N.D. Stafford L.T. Condon M.J.C. Rogers A.W. MacDonald S.L. Atkin 《Clinical otolaryngology》2003,28(4):314-319
The expression of somatostatin receptors 1 and 2 in benign, pre‐malignant and malignant laryngeal lesions The role of chemotherapy in squamous cell carcinoma of the larynx has not been clearly defined. Whilst toxic chemotherapy regimes may confer a marginal improvement in survival, surgery and radiotherapy remain the mainstay of treatment. Somatostatin is a naturally occurring peptide, which exerts antiproliferative and antiangiogenic effects via five membrane‐bound receptor subtypes. The expression of somatostatin receptor subtypes (SSTRs) 1 and 2 was studied in benign, pre‐malignant and malignant laryngeal specimens. Epithelial expression of SSTR1 was detected in 4/6 (67%) Reinke's oedema, 5/6 (83%) pre‐malignant and 8/12 (67%) malignant specimens, with virtually no stromal or vascular expression. High levels of epithelial SSTR2 expression were noted in all Reinke's oedema specimens, compared with low‐to‐moderate levels in only 2/6 (33%) pre‐malignant and 3/12 (25%) malignant specimens (P < 0.01). This ‘loss’ of epithelial SSTR2 expression may provide a growth advantage in pre‐malignant and malignant laryngeal lesions. Vascular expression of SSTR2 was ubiquitous in all groups, with scant stromal expression. Overall, most (>80%) pre‐malignant and malignant laryngeal specimens expressed at least one of the two SSTR subtypes studied. Somatostatin analogues may have a therapeutic role in squamous cell carcinoma of the larynx. 相似文献
74.
75.
仓龙卿 《东南大学学报(医学版)》1993,(2)
分析了92例胸膜活检资料,认为其阳性率与下述因素有关:疾病种类、病例选择、活检器械、取材方法及技术、重复检查、临床医师与病理医师的配合。 相似文献
76.
José Manuel Valdueza Loris Cristante Jörg Freitag Christian Hagel Hans-Dietrich Herrmann 《Neurosurgical review》1995,18(4):273-275
The clinical, neuroradiological, and histological findings of an adult patient suffering from malignant optic glioma is reported. Rapid visual deterioration was misdiagnosed for several months until biopsy confirmed the tumor. The patient died despite radiation therapy nine months after first symptoms. Our presentation will focus on the problems of diagnosing and establishing therapeutic procedures in this rare malignant neoplasm. 相似文献
77.
Recent studies suggest that abnormalities occur at the lipid level in malignant hyperthermia susceptible humans and pigs. To test this hypothesis, we first investigated the physical state of plasma membranes of lymphocytes isolated from normal and malignant hyperthermia susceptible swine. In halothane-challenged pigs, malignant hyperthermia susceptibility was also assessed by ryanodine binding assay on purified sarcoplasmic reticulum membranes. The results clearly show that plasma membrane of lymphocytes from malignant hyperthermic pigs are significantly more fluid than controls. We then attempted to apply the same methodology to lymphocytes prepared from human patients previously diagnosed by the halothane and caffeine contracture test. In that case, there was no clear relationship between malignant hyperthermia susceptibility and the fluidity state of lymphocyte plasma membranes. 相似文献
78.
Akiomi Ogawa Masahiro Takano Kouichi Takagi Osamu Tokunaga Kohji Miyazaki 《Surgery today》1997,27(12):1167-1169
We describe herein a rare case of primary malignant melanoma of the rectum in an 85-year-old woman. The patient presented
with intermittent rectal bleeding, and a colonoscopy revealed an ulcerated polypoid mass in the rectum, located 5 cm from
the anal verge. The lesion was histologically characterized by solid growths of small round cells with scanty cytoplasm and
prominent nucleoli. Although no melanin pigment was found in the tumor cells, they were immunohistochemically positive for
HMB-45, a monoclonal antibody highly specific for malignant melanoma. Thus, HMB-45 proved very useful to establish a diagnosis
of amelanotic malignant melanoma of the rectum. 相似文献
79.
80.
Dr Alistair J. Cochran 《Pathology international》1998,48(2):168-170
The Association of Directors of Anatomic and Surgical Pathology have developed recommendations for the surgical pathology report for common malignant tumors. The recommendations for cutaneous melanoma are reported herein. 相似文献