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排序方式: 共有1834条查询结果,搜索用时 31 毫秒
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Feinmesser M Schachter JM Tobar A Sulkes J Gutman H Kruk N Okon E 《The American Journal of dermatopathology》2002,24(2):108-117
Malignant melanomas, which produce a large number of substances active in connective tissue modulation, must contend with the dermis to grow and propagate. We studied the morphologic interactions between tumorigenic malignant melanomas and dermal elastin. Formalin-fixed and paraffin-embedded tissues of 108 tumorigenic malignant melanomas were stained for elastic tissue with the Verhoeff-van Gieson method. Various aspects of the relationship between malignant melanoma and dermal elastin were analyzed in relation to the histologic and clinical data using univariate and multivariate analyses. Tumor thickness, mitotic rate, and the presence of elastin remnants within the tumors were found to be independent negative prognostic factors, the latter with borderline significance. Tumors with more remnants of elastin were associated with higher stage of disease and lymph node and distant metastases. Tumor infiltration between the elastic fibers in the tumor depth was associated with high Clark level, greater tumor thickness, high stage of disease, and lymph node metastases. At least partial preservation of elastic fibers in the tumor depth was a relatively good prognostic factor whereas complete absence of elastin was an adverse factor. Focal or multifocal absence of elastin in the midst of the tumors or in their depth was usually associated with lymphocytic infiltrates. We suggest that tumors with remnants of elastic fibers and/or invasion between elastic fibers in their depth may be fast growing and highly invasive. The absence of elastin within tumors and at their advancing edge may be related to the elaboration of elastin-degrading substances by melanoma cells or various inflammatory cells. Our findings indicate that the relationship between malignant melanomas and dermal connective tissue components, specifically elastin, may have prognostic significance. 相似文献
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We describe an 18-month-old boy who suffered venous air embolism during an arthrogram. Dangers associated with air injection are emphasized, illustrating the importance of careful monitoring to detect adverse events. We recommend caution when employing this method of hip joint evaluation. 相似文献
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BACKGROUND: Chromogranin A (CGA), Pro-gastrin-releasing peptide (ProGRP) and neuron-specific enolase (NSE) are known as immunohistochemical tissue markers closely associated with neuroendocrine differentiation in non-small-cell lung carcinoma (NSCLC). The aim of the present study was to assess the value of serum levels of these markers in predicting response to chemotherapy and survival of patients with unresectable NSCLC. METHODS: The study included 67 patients with advanced NSCLC treated with chemotherapy. Before treatment, serum levels of CGA, ProGRP and NSE were measured with commercial kits. RESULTS: No association was found between serum NSE and age, gender, histology, performance status or extent of the disease. Distribution of serum CGA differed significantly according to gender and histology, with higher levels being found in men (p = 0.01) and in squamous cell carcinoma (p = 0.01). Serum ProGRP levels correlated with disease extent, being higher in patients with metastatic disease (M1) than in those with locoregional disease (M0; p = 0.02). The association of NSE, CGA and ProGRP levels with response to chemotherapy was not significant. While NSE had no impact on survival, the median survival was shorter for patients with elevated serum CGA and longer for patients with high ProGRP levels. Association with survival was significant when the Classification and Regression Tree (CART)-derived or median cutoff points were explored. On inclusion in multivariate Cox models, both CGA and ProGRP retained significance with high levels showing an opposite effect on survival [CART-derived cutoff points: CGA, relative risk (RR) -4.0; p < 0.001, and ProGRP, RR -0.4; p = 0.006, and median cutoff points: CGA, RR -1.8; p = 0.04, and ProGRP, RR -0.5; p = 0.03]. The combined use of CGA, ProGRP and NSE allowed for definition of two sets of patients with significantly different median survival times (25.2 vs. 8.8 months, p = 0.0001). CONCLUSIONS: In the circulation, CGA and Pro-GRP appear to bear important information related to the prognosis for NSCLC patients before chemotherapy. While a high CGA before treatment was found as an unfavorable prognostic determinant, a high ProGRP conferred a survival advantage. The combined use of serum CGA, ProGRP and NSE may supply additional information to prognosis. 相似文献
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Avi Orr-Urtreger Anat Bar-Shira Dani Bercovich Noa Matarasso Uri Rozovsky Serena Rosner Sonya Soloviov Gad Rennert Luna Kadouri Ayala Hubert Hanna Rennert Haim Matzkin 《Cancer epidemiology, biomarkers & prevention》2006,15(3):474-479
Epidemiologic and genetic studies support the considerable effect of heritable factors on prostate tumorigenesis, although to date, no unequivocal susceptibility gene has been identified. The extensive study of RNASEL in prostate cancer patients worldwide has yielded conflicting results. We reevaluated the role of the RNASEL 471delAAAG Ashkenazi founder mutation in 1,642 Ashkenazi patients with prostate, bladder, breast/ovarian, and colon cancers; Ashkenazi controls; and in non-Ashkenazi prostate cancer patients and controls. The entire RNASEL coding sequence was also screened using denaturing high-performance liquid chromatography and multiplex ligation-dependent probe amplification for possible sequence variations or copy number changes in a population of prostate cancer patients. The 471delAAAG mutation was detected in 2.4% of the Ashkenazi prostate cancer patients; in 1.9% of patients with bladder, breast/ovarian, and colon cancers; and in 2.0% of the Ashkenazi controls. Seven additional variants were detected in RNASEL, including a novel potentially pathogenic splice site mutation, IVS5+1delG, although none were associated with increased prostate cancer risk. Multiplex ligation-dependent probe amplification analysis showed two RNASEL gene copies in all 300 prostate cancer patients tested. We estimated that the RNASEL 471delAAAG founder mutation, which was detected in 2% of the Ashkenazi Jews, originated between the 2nd and 5th centuries A.D., compared with the less frequent (1%) BRCA1 185delAG founder mutation, which originated hundreds of years earlier. Taken together, our analysis does not support a role for the RNASEL 471delAAAG Ashkenazi mutation nor for the other alterations detected in RNASEL in prostate cancer risk in Jewish men. 相似文献
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BACKGROUND: Trans-tubular potassium gradient (TTKG) is considered to reflect mainly aldosterone bioactivity with regard to its kaliuretic response. We determined both TTKG and aldosterone serum concentrations in patients with severe drug-induced hyperkalemia (DIH). METHODS: Ten hyperkalemic patients with serum potassium of more than 5.5 mEq/l, and serum creatinine of less than 2.5 mg/dl (221 micromol/l) were studied prospectively. Two control groups of 10 patients each were used. Control 1 group with normal renal function, and control 2 group with normokalemia and renal failure of the same magnitude as that of the hyperkalemic patients. Serum osmolarity, electrolytes, creatinine, aldosterone and urine electrolytes and osmolarity were measured and TTKG calculated. RESULTS: DIH patients had lower TTKG values than control 1 patients (2.58 +/- 0.36 vs. 6.68 +/- 0.55, p < 0.001), and also lower than that of the control 2 patients (2.58 +/- 0.36 vs. 5.51 +/- 0.87, p < 0.01). Serum aldosterone concentration in the DIH group was higher than that of the control 1 group [24.30 +/- 5.0 vs. 7.4 +/- 2.1 pg/ml (674 +/- 139 vs. 205 +/- 58 pmol/l), p < 0.006] but not different from that of the control 2 group [24.3 +/- 5.0 vs. 15.3 +/- 3.8 pg/ml (674 +/- 139 vs. 424 +/- 106 pmol/l), respectively, p = 0.18]. Although there was some overlap in TTKG between DIH and control groups, 6 of 10 DIH patients had TTKG of less than 2.5, while none of the control patients had such a low value. CONCLUSION: DIH is characterized by lower TTKG values than those observed in patients with normal or mild-to-moderate renal failure. Other factors in addition to aldosterone seem to be involved. 相似文献
98.
Michael Vaiman Gal Shoval Haim Gavriel 《European archives of oto-rhino-laryngology》2008,265(6):663-668
The article discusses the usefulness and technique of investigation of suspected psychogenic dysphagia by surface electromyography
(sEMG) of deglutition. Thirty-two patients with suspected psychogenic dysphagia (Group 1) and 40 healthy individuals (Group
2) were involved in the study. The timing, amplitude and graphic patterns of activity of the masseter, submental, infrahyoid
and trapezius muscles were examined during voluntary single water swallows (“normal”), and continuous drinking of 100 cc of
water. The muscle activity in oral, pharyngeal and initial oesophageal stages of swallowing was measured, and graphic records
were evaluated in relation to timing and voltage. Globus hystericus was found in only 14 patients of the Group 1 (43.75%).
The main sEMG pattern of psychogenic dysphagia is a lack of any pathologic changes of timing, voltage and graphic patterns
of deglutition. In 28% of cases tension of skeletal muscles not involved in deglutition was observed during single swallowing
(vs. 0% in controls). Psychogenic/hysteria-conversion dysphagia has no pathologic sEMG patterns associated with deglutition.
Skeletal muscle tension during deglutition, being observed in some cases has no connection with the act of swallowing itself.
Surface EMG, being non-invasive and non-radiographic, can be used for screening purposes for patients with dysphagia thus
avoiding expensive and time-consuming investigation. 相似文献
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