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Tamoxifen prevents recurrence of breast cancer and is suggested for preventive risk-reducing therapy. Tamoxifen reduces mammographic density, a proxy for therapy response, but little is known about its effects in remodelling normal breast tissue. Our study, a substudy within the double-blinded dose-determination trial KARISMA, investigated tamoxifen-specific changes in breast tissue composition and histological markers in healthy women. We included 83 healthy women randomised to 6 months daily intake of 20, 10, 5, 2.5, 1 mg of tamoxifen or placebo. The groups were combined to “no dose” (0-1 mg), “low-dose” (2.5-5 mg) or “high-dose” (10-20 mg) of tamoxifen. Ultrasound-guided biopsies were collected before and after tamoxifen exposure. In each biopsy, epithelial, stromal and adipose tissues was quantified, and expression of epithelial and stromal Ki67, oestrogen receptor (ER) and progesterone receptor (PR) analysed. Mammographic density using STRATUS was measured at baseline and end-of-tamoxifen-exposure. We found that different doses of tamoxifen reduced mammographic density and glandular-epithelial area in premenopausal women and associated with reduced epithelium and increased adipose tissue. High-dose tamoxifen also decreased epithelial ER and PR expressions in premenopausal women. Premenopausal women with the greatest reduction in proliferation also had the greatest epithelial reduction. In postmenopausal women, high-dose tamoxifen decreased the epithelial area with no measurable density decrease. Tamoxifen at both low and high doses influences breast tissue composition and expression of histological markers in the normal breast. Our findings connect epithelial proliferation with tissue remodelling in premenopausal women and provide novel insights to understanding biological mechanisms of primary prevention with tamoxifen.  相似文献   
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We thank Geluk and Zijlstra for their kind words as well astheir considerations and proposals. The latter hits right intothe heart of the issue: should one stick to the ‘anatomic’paradigm urging us to detect and treat coronary stenoses andcalcifications rather than follow  相似文献   
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OBJECTIVE: Analysis of the effects of a comprehensive focal spasticity program in adult patients. DESIGN: Retrospective study of an out-patient cohort. PATIENTS: One hundred patients were enrolled in the study (54 men and 46 women, mean age 41 years (SD 14). Cerebral palsy and stroke were equally common (80% in total). The remaining patients had miscellaneous diagnoses, including traumatic brain injury. METHODS: On average 230 units (SD 101) of botulinum toxin A Botox was given for 227 principal therapy targets chosen by the patient or the caregiver. One patient could have several targets for therapy. Administration of botulinum toxin was combined with 260 additional therapeutic interventions, most of which were forms of physical therapy. The effects were assessed after 6 weeks and compared with baseline functional abilities 1-2 weeks prior to therapy. RESULTS: Improvement was observed for 211 (93%) therapy targets, no change in 15 (7%), and impairment in 1, corresponding to an overall improvement in 90 patients (90%), 9 unchanged (9%) and worsening in 1. Spasticity assessment (Ashworth scale 0-4; 30 patients) showed a statistically significant improvement (median at baseline was 3 vs 2 after therapy, mean difference 1.2, p<0.001). CONCLUSION: Improvement was observed in >or=90% of patients and in their principal therapeutic targets in a cohort receiving their first focal spasticity treatment with botulinum toxin A and additional therapy. A strict strategy for patient selection and comprehensive management was followed.  相似文献   
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Bone turnover before and after withdrawal of estrogen/gestagen treatment was studied in a randomized trial with 110 healthy female volunteers, who had passed a natural menopause 6 months to 3 years before the start of the study. Urinary excretion of intravenously injected 99m-technetium diphosphonate was measured as an index of bone turnover; plasma bone Gla protein and serum alkaline phosphatase were measured as indices of bone formation; and fasting urinary excretion of hydroxyproline and calcium were measured as estimates of bone resorption. During 2 years of hormone treatment, all variables decreased highly significantly (p less than 0.001) to a constant low level. Three months after withdrawal all variables increased highly significantly (p less than 0.001) towards, but not above, pretreatment and placebo levels. We conclude that withdrawal of estrogen/gestagen replacement therapy in postmenopausal women increases bone turnover, but not in excess of pretreatment values. This indicates that bone loss (after withdrawal) is similar to that seen in the placebo group and that a rebound phenomenon is unlikely.  相似文献   
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