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221.
The colon carcinogen 1,2‐dimethylhydrazine (DMH) was cultured with rat colon epithelial cells to determine if these cells have the ability to metabolize DMH. Colon epithelial cells isolated from conventional and germfree Sprague‐Dawley rats were incubated in CMRL 1066 supplemented medium containing 14C‐DMH. Cells from both groups of rats metabolized DMH to gaseous metabolites, to metabolites in the medium that were putatively identified as azoxymethane and methylazoxymethanol, and to products that bound to DNA. Cells from germfree rats metabolized DMH at an equal or greater rate than cells from conventional rats for the criteria examined. This report demonstrates that rat colon epithelial cells can metabolize DMH without previous metabolism by other tissues or colon bacteria. 相似文献
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Roisin T. Dolan Joseph S. Butler Malcolm R. Kell Thomas F. Gorey Maurice A. Stokes 《The surgeon》2010,8(5):252-258
BackgroundNipple discharge accounts for up to 5% of referrals to breast surgical services. With the vast majority of breast carcinomas originating in the ductal system, symptomatic dysfunction of this system often raises disproportionate clinical concern. The aim of this study is firstly, to evaluate the clinical importance of nipple discharge as an indicator of underlying malignancy and secondly, to assess the diagnostic application of duct cytology in patients presenting with nipple discharge.Study designWe performed a retrospective analysis of all patients presenting with nipple discharge as their primary symptom to the symptomatic breast unit at a tertiary referral center over a 30-month period (n = 313). The Hospital Inpatient Enquiry (HIPE) System and BreastHealth database were used to identify our study cohort. Parameters evaluated included patient demographics, clinical presentation, clinical evaluation, radiological assessment and histological/cytological analysis.ResultsThree-hundred and thirteen patients presented with nipple discharge as their primary complaint. Invasive breast carcinoma was diagnosed by Triple Assessment in 5% of patients. 24% of patients presenting with nipple discharge underwent nipple aspiration and cytological analysis. Duct cytology was diagnostic of the underlying breast carcinoma in 50% of triple assessment diagnosed carcinoma. Four risk factors were identified as having a significant association with breast carcinoma, these included (a) age >50 years (p < 0.0001), (b) bloody nipple discharge (p < 0.008), (c) presence of a breast lump (p < 0.0001) and (d) single duct discharge (p < 0.006).ConclusionsNipple discharge is a poor indicator of an underlying malignancy. Use of nipple aspiration and duct cytology for the assessment of nipple discharge is of limited diagnostic benefit. However, by utilizing the systematic, gold standard approach of Triple Assessment (clinical, radiological and cytological evaluation), the risk of underlying carcinoma can be accurately defined. 相似文献
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Sam CK Cheng BScOptom Maurice KH Yap PhD MCOptom FAAO Ernest Goldschmidt MD DrSci Peter G Swann BSc MAppSc FCOptom FAAO honFIES Larry HY Ng PDOptom OD FAAO FBCLA Carly SY Lam PhD MSc MCOptom FAAO 《Clinical & experimental optometry》2008,91(4):373-378
Background: Optomap uses the ultra‐wide field scanning laser ophthalmoscopy to provide retinal examination. It permits fundus examination without the use of a mydriatic, which is more comfortable for the patients. This paper determines the sensitivity and specificity of the Optomap for detecting retinal signs under non‐mydriatic conditions. Methods: Fifty‐four eyes identified with retinal/choroidal signs and eight normal eyes were recruited from 31 Hong Kong Chinese subjects. Photo‐documentation of fundal changes was obtained with the Optomap under non‐mydriatic conditions before a dilated fundus examination by a clinician using standard procedures. The eyelid was retracted using a cotton bud when necessary. Dilated fundus examinations were performed by another clinician using binocular indirect ophthalmoscopy and slitlamp biomicroscopy with a fundus lens. The Optomap images were evaluated by four other investigators under masked condition. The International Classification of Disease, Ninth Revision (ICD‐9‐CM) was adopted for recording retinal features. Screening results were compared with those obtained using the dilated fundus examination as the gold standard. Results: The cotton bud method for eyelid retraction showed an improvement in the area of retina that could be visualised. The sensitivity and specificity of the Optomap averaged 76.4 and 71.9 per cent, respectively. Some fundal signs were missed by all observers in the Optomap but not with the biomicroscope. These included white‐without‐pressure, lattice degeneration, paramacular drusen and pigmentary changes at central fundus. Conclusion: Optomap serves as a reliable screening tool for fundus examination especially because it covers a much wider area of the peripheral retina than other digital instruments for fundus photography. 相似文献
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The essential difficulty of these adolescents suffering of anorexia nervosa lies within their personalities and their incapacity to deal with conflict. The relationships of these patients to others are similar to their relationships to food: both are often characterized by a paradoxical aspect: an alternating between a great eagerness for relationships and a capacity for isolation and withdrawal, with intolerance for loneliness; a great awareness of the attitude and the opinion of others; difficulties in regulating relationships and in finding optimal distancing; oscillation between an anxiety due to fear of separation and an anxiety due to fear of intrusion; the coexistence of exacerbated expectations concerning important people, along with the ability to be easily influenced, but at the same time a large capacity for opposition and an obstinate refusal of change. Globally these characteristics find a common ground in the concept of dependency. In all these patients there is a predisposition towards an exaggerated dependency on certain people in the outside world, especially parents with a lack of autonomy. The psychopathological significance of these conducts; its stakes, and its therapeutical consequences are discussed. 相似文献
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Association of an extracellular matrix gene cluster with breast cancer prognosis and endocrine therapy response 总被引:1,自引:0,他引:1
Jozien Helleman Maurice P H M Jansen Kirsten Ruigrok-Ritstier Iris L van Staveren Maxime P Look Marion E Meijer-van Gelder Anieta M Sieuwerts Jan G M Klijn Stefan Sleijfer John A Foekens Els M J J Berns 《Clinical cancer research》2008,14(17):5555-5564
PURPOSE: We previously discovered an extracellular matrix (ECM) gene cluster associated with resistance to first-line tamoxifen therapy of patients with metastatic breast cancer. In this study, we determined whether the six individual ECM genes [collagen 1A1 (COL1A1), fibronectin 1 (FN1), lysyl oxidase (LOX), secreted protein acidic cysteine-rich (SPARC), tissue inhibitor of metalloproteinase 3 (TIMP3), and tenascin C (TNC)] were associated with treatment response, prognosis, or both. EXPERIMENTAL DESIGN: In 1,286 primary breast tumors, mRNA expression (quantitative real-time PCR) was related to clinicopathologic factors and disease outcome in univariate and multivariate analysis including traditional factors. RESULTS: TIMP3, FN1, LOX, and SPARC expression levels (continuous variables) were significantly associated with distant metastasis-free survival (MFS) in 680 lymph node-negative untreated patients (P<0.03). Using a calculated linear prognostic score, these patients were evenly divided into five prognostic groups with a significant difference in 10-year MFS of approximately 40% between the two extreme prognostic groups. Furthermore, high TNC expression as continuous variable was associated with (a) shorter MFS in 139 estrogen receptor-positive and lymph node-positive patients who received adjuvant tamoxifen therapy (hazard ratio, 1.53; P=0.001), and (b) no clinical benefit (odds ratio, 0.81; P=0.035) and shorter progression-free survival (hazard ratio, 1.19; P=0.002) in 240 patients in whom recurrence was treated with tamoxifen as first-line monotherapy. These results were also significant in multivariate analyses. CONCLUSION: FN1, LOX, SPARC, and TIMP3 expression levels are associated with the prognosis of patients with breast cancers, whereas TNC is associated with resistance to tamoxifen therapy. Further validation and functional studies are necessary to determine the use of these ECM genes in decisions regarding treatment and whether they can serve as targets for therapy. 相似文献