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31.
Raloxifene hydrochloride binds to the estrogen receptor and shows tissue‐selective effects; thus, it belongs to a class of drugs recently described as selective estrogen receptor modulators (SERMs). Tissue selectivity of raloxifene may be achieved through several mechanisms: the ligand structure, interaction of the ligand with different receptor subtypes in various tissues, and intracellular events after ligand binding. Raloxifene has estrogen‐agonist effects on bone and lipids and estrogen antagonist effects on the breast and uterus. In addition to its well established effects on osteoporosis, recent preclinical and clinical findings suggest that raloxifene also possesses beneficial effects on the cardiovascular system. These findings indicated that raloxifene may have cardioprotective properties without an increased risk of cancer or other side effects. Raloxifene has been shown to reduce total and low‐density lipoprotein cholesterol concentrations in plasma, an effect similar to that produced by estrogens. Unlike estrogens, however, raloxifene does not increase high‐density lipoprotein cholesterol and triglyceride levels in plasma. Endothelium is thought to play an important role in the genesis of atherosclerosis. Several lines of evidence suggest that an intervention with endothelial function might influence the progression of coronary disease and the incidence of cardiovascular events. Raloxifene increases the nitric oxide/endothelin‐1 ratio, and improves endothelium‐dependent vasomotion in post‐menopausal women to the same extent as estrogens. Furthermore, in two randomized trials on post‐menopausal women raloxifene reduced homocysteine levels, another independent risk factor for the development of cardiovascular disease. Although estrogens remain the drugs of choice in the hormonal therapy of most postmenopausal women, raloxifene may represent an alternative in women who are at risk of coronary artery disease.  相似文献   
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Bone stress injuries, whose incidence is increasing among competitive and recreational athletes, represent a pathophysiological continuum along which a bone responds to a changing mechanical environment. Frank stress fracture is the endpoint of this process, resulting from the accumulation of microinjuries due to repeated abnormal stresses. The legs are largely the most frequently affected bone district. The aim of this paper is to review the imaging findings of the whole spectrum of stress-induced bone lesions of the leg in athletes. We emphasise the role of computed tomography and magnetic resonance imaging, which allow recognition of early alterations.  相似文献   
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Rarely, hypertrophic cardiomyopathy can be associated with ST elevation on electrocardiogram. We report a rare case of anterior hypertrophic cardiomyopathy mimicking an acute myocardial infarction where the diagnosis of myocardial hypertrophy was made by cardiac magnetic resonance. The method was able to identify the myocardial hypertrophy located in basal segments of anterior wall respect to echocardiography.  相似文献   
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Background and aimsThe WHO Global Action Plan for the Prevention of non-communicable diseases (NCDs) recommends a 30% relative reduction in mean population salt/sodium intake. The study assessed the trend in the habitual salt intake of the Italian adult population from 2008 to 2012 to 2018–2019 based on 24-h urinary sodium excretion, in the framework of the CUORE Project/MINISAL-GIRCSI/MENO SALE PIU’ SALUTE national surveys.Methods and resultsData were from cross-sectional surveys of randomly selected age and sex–stratified samples of resident persons aged 35–74 years in 10 (out of 20) Italian Regions distributed in North, Centre and South of the Country. Urinary sodium and creatinine measurements were carried out in a central laboratory. The analyses included 942 men and 916 women examined in 2008–2012, and 967 men and 1010 women examined in 2018–2019. The age-standardized mean daily population salt (sodium chloride) intake was 10.8 g (95% CI 10.5–11.1) in men and 8.3 g (8.1–8.5) in women in 2008–2012 and respectively 9.5 g (9.3–9.8) and 7.2 g (7.0–7.4) in 2018–2019. A statistically significant (p<0.0001) salt intake reduction was thus observed over 10 years for both genders, and all age, body mass index (BMI) and educational classes.ConclusionsThe average daily salt intake of the Italian general adult population remains higher than the WHO recommended level, but a significant reduction of 12% in men and 13% in women has occurred in the past ten years. These results encourage the initiatives undertaken by the Italian Ministry of Health aimed at the reduction of salt intake at the population level.  相似文献   
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The effects of recombinant human erythropoietin (rHuEPO) in diabetes-related healing defects were investigated by using an incisional skin-wound model produced on the back of female diabetic C57BL/KsJ-m(+/+)Lept(db) mice (db(+)/db(+)) and their normoglycemic littermates (db(+/+)m). Animals were treated with rHuEPO (400 units/kg in 100 microl s.c.) or its vehicle alone (100 microl). Mice were killed on different days (3, 6, and 12 days after skin injury) for measurement of vascular endothelial growth factor (VEGF) mRNA expression and protein synthesis, for monitoring angiogenesis by CD31 expression, and for evaluating histological changes. Furthermore, we evaluated wound-breaking strength at day 12. At day 6, rHuEPO injection in diabetic mice resulted in an increase in VEGF mRNA expression (vehicle = 0.33 +/- 0.1 relative amount of mRNA; rHuEPO = 0.9 +/- 0.09 relative amount of mRNA; P < 0.05) and protein wound content (vehicle = 23 +/- 5 pg/wound; rHuEPO = 92 +/- 12 pg/wound; P < 0.05) and caused a marked increase in CD31 gene expression (vehicle = 0.18 +/- 0.05 relative amount of mRNA; rHuEPO = 0.98 +/- 0.21 relative amount of mRNA; P < 0.05) and protein synthesis. Furthermore, rHuEPO injection improved the impaired wound healing and, at day 12, increased the wound-breaking strength in diabetic mice (vehicle = 12 +/- 2 g/mm; rHuEPO 21 +/- 5 g/mm; P < 0.05). Erythropoietin may have a potential application in diabetes-related wound disorders.  相似文献   
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PURPOSE: To prospectively compare computed tomography (CT), magnetic resonance (MR) imaging, and bone scintigraphy in athletes with clinically suspected early stress injury of tibia. MATERIALS AND METHODS: Medical ethics committee approval and informed consent were obtained. A total of 42 patients experiencing tibial pain due to early stress injuries were evaluated. Eight patients had bilateral involvement; thus, 50 tibiae were evaluated. All patients underwent initial radiography that was negative for injury. MR imaging, CT, and bone scintigraphy were performed in all patients within 1 month of onset of symptoms. Ten asymptomatic volunteers served as the control group. Location of stress injuries, types of bone alterations, and presence of periosteal and bone marrow edema were evaluated. Sensitivity, specificity, accuracy, and positive and negative predictive values of MR imaging and CT were assessed, as was sensitivity of bone scintigraphy. McNemar test was used to detect statistically significant differences. RESULTS: Sensitivity of MR imaging, CT, and bone scintigraphy was 88%, 42%, and 74%, respectively. Specificity, accuracy, and positive and negative predictive values were 100%, 90%, 100%, and 62%, respectively, for MR imaging and 100%, 52%, 100%, and 26%, respectively, for CT. Significant difference in detection of early tibial stress injuries was found between MR imaging and both CT and bone scintigraphy (McNemar test; P < .001 and P = .008, respectively). CONCLUSION: MR imaging is the single best technique in assessment of patients with suspected tibial stress injuries; in some patients with negative MR imaging findings, CT can depict osteopenia, which is the earliest finding of fatigue cortical bone injury.  相似文献   
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CT and MR findings in neoplastic perineural spread along the vidian nerve   总被引:2,自引:0,他引:2  
The aims of this article are to describe the findings of perividian tumor spread and to compare the accuracy of MRI and CT in diagnosing perineural metastasis along the vidian nerve. Moreover, the frequency of perividian metastasis in patients with head and neck cancer was evaluated. The CT and MR examinations of 98 consecutive untreated patients with histologically proven head and neck cancer were retrospectively reviewed. We considered as criteria for perineural tumor spread along the vidian nerve the following CT and MR findings: For CT (a) enlargement of the pterygoid canal, (b) erosion of its bony wall, and (c) obliteration of its normal fatty content; and for MR (a) enlargement of the vidian nerve, (b) enhancement of the nerve, and (c) obliteration of fat, particularly in the anterior part of the pterygoid canal. Ten patients met the selected criteria for perineural metastasis, which was bilateral in 3 patients, with a total of 13 vidian metastases. The CT scans demonstrated unilateral involvement of the vidian nerve in 9 patients. The MRI scans showed 13 perineural metastases. In 3 patients MR scans demonstrated involvement of four vidian nerves that appeared normal on CT examinations. The diagnostic difference between CT and MRI was statistically significant (Fisher's exact test; p = 0.04). Perineural spread along the vidian nerve is an event more frequent than previously reported and must be investigated with a careful imaging technique. Although a major limitation of our study is the lack of histological proof, the MR finding of a significant enhancement of the nerve, whether enlarged or normal in size, could be considered very suggestive of this kind of metastatic spreading, particularly if associated with simultaneous involvement of the neighboring structures (pterygopalatine fossa, foramen lacerum, trigeminal branches, etc.). Received: 5 January 1999; Revision received 11 May 1999; Accepted: 17 June 1999  相似文献   
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