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581.
Sarcoidosis is a systemic granulomatous disease of unknown aetiology. The breast is involved in less than 1% of cases. Breast can be either a primary or a secondary site of presentation. Breast sarcoidosis often mimics carcinomas at clinical examination. We report a case of breast sarcoidosis detected during screening mammography in a 57-year-old woman. The lesion presented as a 1.4 cm nodule located in the right breast. On histology, it was characterized by non-caseating giant cell granulomas. Differential diagnoses included idiopathic granulomatous mastitis, tuberculosis, fungal infection, cat-scratch disease and sarcoid-like reactions to cancer. Further clinical and laboratory investigations were consistent with a diagnosis of sarcoidosis. Specifically, serum levels of angiotensin-converting enzyme (ACE) were elevated and a CT scan showed small bilateral pulmonary nodules distributed along the pleura and bronchovascular bundles (perilymphatic pattern), as well as enlarged bilateral hilar and mediastinal lymph nodes. The patient received corticosteroid treatment, and is presently asymptomatic. Breast involvement by sarcoidosis, although rare, should be considered when dealing with granulomatous lesions of the breast.  相似文献   
582.
To clarify the role of gene polymorphisms on the effect of losartan and losartan plus hydrochlorothiazide on blood pressure (primary end point) and on cardiac, vascular and metabolic phenotypes (secondary end point) after 4, 8, 12, 16 and 48 weeks treatment, an Italian collaborative study - The Study of the Pharmacogenomics in Italian hypertensive patients treated with the Angiotensin receptor blocker losartan (SOPHIA) - on never-treated essential hypertensives (n = 800) was planned. After an 8 week run-in, losartan 50 mg once daily will be given and doubled to 100 mg at week +4 if blood pressure is more than 140/90 mmHg. Hydroclorothiazide 25 mg once daily at week +8 and amlodipine 5 mg at week +16 will be added if blood pressure is more than 140/90 mmHg. Cardiac mass (echocardiography), carotid intima-media thickness, 24 h ambulatory blood pressure, homeostatic model assessment (HOMA) index, microalbuminuria, plasma renin activity and aldosterone, endogenous lithium clearance, brain natriuretic peptide and losartan metabolites will be evaluated. Genes of the renin-angiotensin-aldosterone system, salt sensitivity, the beta-adrenergic system and losartan metabolism will be studied (Illumina custom arrays). A whole-genome scan will also be performed in half of the study cohort (1M array, Illumina 500 GX beadstation).  相似文献   
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Forty-three patients with liver metastases were imaged using 14 different pulse sequences (average, 7.5 sequences per patient) to allow direct comparison of their performance. "T2-weighted" spin-echo (SE) images, "T1-weighted" inversion recovery (IR) images, and "T1-weighted" SE images were obtained using a wide range of timing parameters. Pulse sequence performance was quantitated by measuring liver signal-to-noise (S/N) ratios and cancer-liver signal difference-to-noise (SD/N) ratios. Data were standardized to reflect a constant imaging time of 9 minutes for all pulse sequences. The SE 2,000/120 (TR [repetition time]/TE [echo time]) sequence resulted in the greatest SD/N ratio of the T2-weighted SE sequences but also yielded the low S/N ratios, poor anatomic resolution, and motion artifacts common to all T2-weighted SE images. IR sequence images were also sensitive to motion artifacts because of the use of a long TR (1,500 msec). Short TR/TE T1-weighted SE sequences (SE 260/18) had the greatest SD/N ratio (P less than .05), S/N ratio, and anatomic resolution. Furthermore, extensive signal averaging appears to be a powerful solution to all types of motion artifacts in the abdomen.  相似文献   
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