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91.
Tubular adenoma (TA) and syringocystadenoma papilliferum (SCAP) may show histopathological overlap, with some lesions having features of both neoplasms (SCAP + TA). TA has been recently suggested to represent a carcinoma. Four observers blindly assessed 67 cases of TA, SCAP, and their lookalikes (poroma, apocrine adenoma, apocrine carcinoma; all lesions focally featuring a pseudopapillary pattern), and classified the lesions into one of four categories: (1) TA, (2) SCAP, (3) SCAP + TA, and (4) others. Lesions were also classified as benign or malignant. In only 29 cases was there unanimous agreement among the four observers, who classified 22 lesions as TA, three as SCAP, and four cases as others. Of the 38 cases where there was interobserver diagnostic variation, in 30, the diagnosis varied between TA or SCAP or SCAP + TA; the remainder fell in the others category. Analysis of the factors leading to interobserver variability indicated that diagnostic problems occurred when there were any of the following: epidermal acanthosis, papillomatosis, connection of the neoplastic tubules to the overlying epidermis and/or follicular infundibula, and plasma cell infiltration. These features accounted for the morphological overlap between TA and SCAP. All observers agreed that the lesions were benign; the only apocrine carcinoma included was recognized as such by all observers. From the study, it was concluded that TA may arise in the deep dermis without any epidermal connection, or, in other cases, it may be more superficially located with or without an epidermal connection. It may be reasonably inferred that, possibly as a response to infection, there may be accompanying plasma cells and variable acanthosis and papillomatosis, such that the appearances are those of "pure" SCAP, or lesions may have features "intermediate" or overlapping between TA and SCAP.  相似文献   
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Nine Italian population samples, for a total of 12,365 males and 8,043 females aged 11 to 84, were examined. The age and sex distribution of HDL-cholesterol levels were calculated for studying its relationship with major cardiovascular risk factors, and for estimating its predictive power on coronary events and on all causes of mortality.Mean values of HDL-cholesterol in the pool of the samples ranged, according to different age groups, from 46.4 to 56.8 mg/dl in males and from 53.7 to 55.8 mg/dl in females.The linear correlation coefficients between HDL-cholesterol and 10 risk factors did not show high levels except those with triglycerides in men aged 20-34 (–0.33) and 35–64 (–0.34).Using the multiple linear regression model the levels of HDL-cholesterol were estimated as a function of the 10 risk factors solving 4 equations (for males, females and for two age groups, 20–34 and 35–64). The factors showing significant coefficients were body mass index (negative), triglycerides (negative), cigarette smoking (negative), alcohol consumption (positive), physical activity (positive), and non-HDL-cholesterol (negative).The Cox model was used for the prediction of coronary death and all causes of death and the logistic function for the prediction of coronary incidence in two of the studies on men aged 46–65 (6 year follow-up) and aged 60–79 (5 year follow-up), and including 5 other factors as possible confounders. Only the univariate prediction of coronary deaths in one study (men aged 46–65) provided a significant coefficient for HDL-cholesterol (t = –2.7624).Corresponding author.See appendix for the composition of the 6 Research Groups.  相似文献   
95.
Summary: We reviewed the results of imaging studies on 111 children and adolescents with partial epilepsy to determine which imaging procedure had the greatest sensitivity and specificity for partial epilepsy in this age range. All cases were classified as idiopathic, lesional, and cryptogenic epilepsy based on the 1989 International League Against Epilepsy Classification. All patients had magnetic resonance imaging (MRI) and 98 also had computed tomography (CT). Thirty patients with negative CT had MRI lesions that were most likely the cause of the epilepsy, and the initial diagnosis of cryptogenic partial epilepsy was changed to lesional partial epilepsy. We concluded that CT use is unwarrantedly common. MRI should be considered the procedure of first choice. CT has a complementary role, and functional neuroimaging should be encouraged.  相似文献   
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The presence of epidermal growth factor, estrogen, and progesterone receptors (EGFR, ER, and PR) was investigated by a competitive binding assay in 43 colorectal adenocarcinomas and 32 normal colorectal mucosa specimens. EGFR were expressed in most of the tumor specimens analyzed at levels comparable with normal mucosa. There was no correlation between EGFR and tumor localization, tumor size, tumor stage, and grading. Among tumor specimens, 13.9% and 6.9% expressed very low but detectable ER and PR levels, respectively. No statistically significant difference was found between steroid hormone receptor levels in the tumor and normal mucosa specimens, and neither was there any correlation of ER and PR with the pathological findings. Our results suggest that the EGFR system may play a role in regulating the growth of colorectal tissues. Further studies should demonstrate whether, despite the lack of correlation with histopathological parameters, EGFR expression may have a biological significance in human colorectal cancer.  相似文献   
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The relationship between smoking habits and plasma thiocyanate levels has been evaluated in four adult samples of the general population containing men and women aged 20–84 and in a sample of 11-year-old non-smoking children of both sexes, for a total of 7577 individuals.Mean levels of plasma thiocyanate was found be approximately 20 mol/l in children, 30 mol/l in non-smoking adults and increasingly higher in smoking adults.The slopes of the regression equations of thiocyanate on cigarettes smoked per day range from 3.041 to 5.740, with correlation coefficients of from 0.638 to 0.809. In another occupational sample of 280,2 men aged 46 to 65, where the correlation coefficient (between cigarette consumption and thiocyanate) was only 0.49, plasma thiocyanate was a better predictor of 4 year fatal events than cigarette consumption, 4 other covariates being considered in the same mulivariate model.Corresponding author.  相似文献   
100.
AIMS: Predicting the clinical behaviour of gastrointestinal stromal tumours (GISTs) is difficult and criteria delineating benign from malignant cases are not firmly established. The aims of this study were to define the clinicopathological and molecular features of 66 GISTs, and to determine whether any specific parameters were associated with patient outcome. METHODS: Archival cases of GIST from two major teaching hospitals in Western Australia were studied. Inclusion criteria for the study were: (1) appropriate morphology, (2) CD117 positivity, (3) adequacy of pathological material for study, and (4) exclusion of other tumour types on the basis of immunophenotypic and/or ultrastructural features. Expression of CD117, CD34, S100 protein, keratin (using broad spectrum MNF116), alpha-smooth muscle actin (SMA) was determined by immunohistochemistry. PCR and single strand conformation polymorphism (PCR-SSCP) analysis were used to screen for mutations in exons 11 and 9 of c-kit. RESULTS: There were equal numbers of males and females with a mean age at diagnosis of 60 years, followed up for a mean of 54 months. Thirteen patients (21%) had died of GIST by the end of the study. Tumours were mostly located in the stomach (67%) and small intestine (SI; 25%). The cell types were pure spindle (68%), pure epithelioid (12%) and mixed epithelioid/spindle (20%). c-kit mutations were found in 69% of GISTs, with the large majority (91%) occurring in exon 11. Size > or = 10 cm, tumour necrosis and pure epithelioid cell morphology each were the only factors significantly associated with adverse survival (p=0.038, and p=0.047 and p=0.028, respectively). Mitotic activity > or = 5/50 HPF showed a definite trend association with adverse survival, but unlike some other studies, did not achieve statistical significance (p=0.067). c-kit mutations were more frequent in small intestinal GISTs (p=0.05) and in those with pure spindle cell morphology (p=0.023) but were not associated with patient outcome. CONCLUSION: In this study, size > or = 10cm, necrosis and/or pure epithelioid cell morphology correlated significantly with adverse survival. Mitotic activity showed a strong association with survival but this did not reach statistical significance. c-kit mutations occurred mainly in GISTs of the SI, and in purely spindle cell tumours. While the mutation status did not associate with patient outcome in this series, this remains a controversial issue, and further studies are needed to assess whether the type of mutation affects response to tyrosine kinase inhibitor therapy in metastatic GISTs. CD117 staining of any mesenchymal lesion of the gastrointestinal tract should be mandatory for accurate classification. PCR-SSCP analysis is a fast, sensitive and relatively inexpensive method of analysing c-kit mutations, which may be important prognostically and also of therapeutic relevance in the assessment of new tyrosine kinase inhibitor therapies.  相似文献   
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