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1.
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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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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In the present experiments we have investigated the influence of wall shear rate and axial position on platelet and fibrin deposition which results when flowing human non-anticoagulated blood is exposed to either non-procoagulant fibrillar collagen (human type III) or procoagulant subendothelium (rabbit aorta). Platelet adhesion, thrombus volume and fibrin deposition were morphometrically evaluated at axial positions of 1 and 13 mm following perfusions for 5 min at shear rates of 100, 650 and 2,600 s-1. An axially-dependent decrease of platelet adhesion (34-57%, p less than 0.01-0.05) and thrombus volume (57-80%, p less than 0.05) was observed on collagen at all shear rates. On subendothelium, an axially-dependent decrease was observed for platelet adhesion only at 100 s-1 (29%; p less than 0.01) and for thrombus volume at shear rates of 650 s-1 and above (49-58%, p less than 0.01). Deposition of fibrin on subendothelium was axially decreased (16-42%, p less than 0.05) at all shear rates, while no significant axial differences were seen on collagen. However, substantially more fibrin was deposited on the subendothelium (p less than 0.05), and the upstream platelet adhesion and thrombus volume were lower than on collagen (p less than 0.05) at 100 s-1 and 650 s-1. The axially-dependent phenomena on the two surfaces are consistent with the concept of rapid-growing upstream thrombi which deplete the blood layer streaming adjacent ot the surface of platelets, leading to decreased platelet deposition further downstream.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Thylakoids are membranes isolated from plant chloroplasts which have previously been shown to inhibit pancreatic lipase/colipase catalysed hydrolysis of fat in vitro and induce short‐term satiety in vivo. The purpose of the present study was to examine if dietary supplementation of thylakoids could affect food intake and body weight during long‐term feeding in mice. Female apolipoprotein E‐deficient mice were fed a high‐fat diet containing 41% of fat by energy with and without thylakoids for 100 days. Mice fed the thylakoid‐enriched diet had suppressed food intake, body weight gain and body fat compared with the high‐fat fed control mice. Reduced serum glucose, serum triglyceride and serum free fatty acid levels were found in the thylakoid‐treated animals. The satiety hormone cholecystokinin was elevated, suggesting this hormone mediates satiety. Leptin levels were reduced, reflecting a decreased fat mass. There was no sign of desensitization in the animals treated with thylakoids. The results suggest that thylakoids are useful to suppress appetite and body weight gain when supplemented to a high‐fat food during long‐term feeding. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
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Background  

It is well known that physicians' night-call duty may cause impaired performance and adverse effects on subjective health, but there is limited knowledge about effects on sleep duration and recovery time. In recent years occupational stress and impaired well-being among anaesthesiologists have been frequently reported for in the scientific literature. Given their main focus on handling patients with life-threatening conditions, when on call, one might expect sleep and recovery to be negatively affected by work, especially in this specialist group. The aim of the present study was to examine whether a 16-hour night-call schedule allowed for sufficient recovery in anaesthesiologists compared with other physician specialists handling less life-threatening conditions, when on call.  相似文献   
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