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31.
Fully inverting spins, instead of merely saturating them, provides superior contrast for tagging procedures. The resulting improvement in tag contrast-to-noise ratio (CNR) yields higher-precision tag detection. Also, thinner slices and hence reduced tag separations can be employed, providing displacement and strain measurements with better spatial resolution. Alternatively, the improved tag contrast can be used to obtain cine images covering a greater portion of the cardiac cycle. The use of standard magnitude reconstruction for images of these inversion tags causes rectification of the negative-valued signals from the tags, confounding the image interpretation. Therefore, a phase-sensitive reconstruction scheme of the inverted tags must be employed. Here we demonstrate the implementation of inverted tags with phase-sensitive reconstruction in a ramped-flip-angle, steady-state free precession (SSFP) sequence.  相似文献   
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A lump on the midface of a child can pose as a diagnostic dilemma. There is a wide variety of possible differential diagnoses, ranging from simple benign conditions such as a sebaceous cyst, dermoid cyst, lipoma, neuroma and neurofibroma, to potentially devastating conditions such as odontogenic myxoma.A case of a child in which the formulation of a definite diagnosis was clinically and histologically challenging is presented.  相似文献   
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A near-patient testing facility was provided at an anticonvulsant clinic and compared with the previously offered service. Productivity was increased by over 20%, with savings in medical and nursing staff time. This saving in time is offset by increased consumable costs but still enables a significant net saving.  相似文献   
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Segmented cine MRI generally requires breath-holding, which can be problematic for many patients. Navigator echo techniques, particularly successful for free-breathing coronary MRA, are incompatible with the acquisition strategies and SSFP pulse sequences commonly used for cine MRI. The purpose of this work is to introduce a new self-gating technique deriving respiratory gating information directly from the raw imaging data acquired for segmented cine MRI. The respiratory self-gating technique uses interleaved radial k-space sampling to provide low-resolution images in real time during the free-breathing acquisition that are compared to target expiration images. Only the raw data-producing images with high correlation to the target images are included in the final high-resolution reconstruction. The self-gating technique produced cine series with no significant differences in quantitative image sharpness to series produced using comparable breath-held techniques. Because of the difficulties associated with breath-holding, the respiratory self-gating technique represents an important practical advance for cardiac MRI. , Inc.  相似文献   
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PURPOSE: To compare scleral Tono-Pen (Medtronic Solan, Jacksonville, FL) readings to corneal Tono-Pen readings. METHODS: Intraocular pressure (IOP) was measured prospectively in 72 eyes of 37 adult patients and in 10 eyes of 5 children. Measurements were taken on the central cornea and on the sclera. Recorded measurements were within 5% confidence levels by Tono-Pen. RESULTS: Corneal IOP ranged from 10 to 28 mm Hg (mean +/- standard deviation, 17.0 +/- 3.8 mm Hg). Scleral measurements ranged from 4 to 99 mm Hg (40.4 +/- 23.0 mm Hg). Scleral measurements ranged from 11 mm Hg lower to 76 mm Hg higher than corneal measurements. CONCLUSIONS: Tono-Pen readings obtained from sclera are of no clinical value and should not be used to approximate corneal IOP.  相似文献   
39.
Studies have found naltrexone useful in the treatment of diseases other than opiate addiction in which endogenous opioids presumably play a role, such as alcoholism and eating disorders. Some of these studies involve high doses (100–200 mg bid). Because investigational studies with high doses (300 mg/day) reported clinically significant increases in liver enzyme levels, the authors measured a spectrum of liver function parameters in response to high doses of naltrexone in a double-blind, crossover trial (100 mg bid) followed by an open-label period (200 mg bid). They observed no adverse clinical or laboratory changes in liver function in association with high-dose naltrexone therapy in eating disorders.  相似文献   
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BACKGROUND: Acquired cerebriform intradermal naevus (CIN) is a rare form of pseudo cutis verticis gyrata. CASE REPORT: A case of acquired CIN of the scalp in a 46-year-old male patient is presented. The clinical and histopathological presentations of CIN are described and the therapeutic possibilities are discussed. CONCLUSIONS: In each individual case the physician must decide whether to do surgery or follow a wait-and-see policy. There is little risk of malignant change of CIN, and surgical excision of such lesions often involves evident mutilation.  相似文献   
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