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41.
Magnetic resonance imaging of the adrenal glands was performed in 9 patients with Addison’s disease to evaluate the role of magnetic resonance (MR) in this entity. All patients had bilateral adrenal masses demonstrated by computed tomography (CT); etiologies included adrenal hemorrhage (2 patients), granulomatous disease (1 patient), adrenal lymphoma (3 patients), and adrenal metastases (3 patients). Spin-echo axial images were obtained at repetition times (TR) 0.5, 2.0 s and TE 28, 56 ms, using a Diasonics superconducting magnet operating at 0.35 T. In the patients with lymphoma, metastases, and granulomatous disease, the adrenal masses appeared hypointense or isointense with liver on the T1-weighted images (TR 0.5 s, TE 28 ms). In cases of adrenal hemorrhage, areas of hyperintensity were seen on TR 0.5, TE 56 ms sequences, due to shortening of T1 values. In both groups of patients the masses were hyperintense on T2 weighted sequences. Mean calculated T1 of the hemorrhagic glands was 449 ms, compared with a mean of 782 ms for mestastases and lymphoma. While MR is not capable of distinguishing between acute inflammatory and metastatic disases of the adrenal glands, it may be equally efficacious as CT in suggesting the diagnosis of adrenal hemorrhage in patients with Addison’s disease. 相似文献
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The well established differential pulmonary handling of angiotensins I and II indicates the possibility that vascular receptors for the deca- and octa-peptides do not necessarily involve common sites in the renal vasculature either. Experimental findings involving haemodynamic changes within the kidney in anaesthetised and conscious sheep, with utilization of the angiotensins, and also of noradrenaline, are briefly presented; the implications of the intra-renal water and creatinine transfers are discussed, especially as they concern the possible location of angiotensin receptors in the renal blood vessels. Other aspects of the relationships between the peptides are also taken into account particularly with regard to a postulated angiotensin I [NaCl] dependent peritubular capillary antidiuretic action, angiotensin converting enzyme inhibition, Goldblatt clamp induced hypertension and blood flow through the hind-limbs. 相似文献
44.
Shirley Kobar Coni C Francis Samantha MaWhinney Teresa Sharp 《Nutrition in clinical practice》2003,18(5):417-421
BACKGROUND: Development of an acclimation protocol for use when measuring resting energy expenditure (REE) would simplify and standardize data collection. The purpose of this study was to determine if our 2 metabolic carts could be used interchangeably and to determine if excluding the first 3 or 5 minutes of data collected as an acclimation period would significantly improve the coefficients of variation (CVs) for oxygen consumed (VO(2)) and carbon dioxide produced (VCO(2)) when performing REE assessments with our metabolic cart systems. METHODS: Thirteen healthy, nonsmoking adults ranging in age from 32 to 45 years, with activity levels ranging from sedentary to highly active, participated. Indirect calorimetry was performed twice in the morning after 30 minutes of supine resting. Subjects had fasted for 12 hours, and did not exercise within the last 24 hours. The system order for testing was randomized for the first measurement. When the first measurement was completed, subjects were crossed over for measurement using a second metabolic cart. RESULTS: The CVs for VO(2) and VCO(2) were significantly lower when excluding the first 3 (VO(2), p = .0005), (VCO(2), p = .0024) or 5 minutes (VO(2), p = .0001, VCO(2), p = .0021) of data compared with no exclusions. No significant differences in CVs between the 3- and 5-minute exclusions were found for VO(2) (p = .3224) or VCO(2) (p = .2255). CONCLUSIONS: Clearly, our machines cannot be used interchangeably within a study. An acclimation period improves CVs of VO(2) and VCO(2.) The similarities in CVs led us to adopt a 3-minute acclimation period for measuring REE. 相似文献
45.
A device called the Dex Frame has recently been marketed as an aid for children with specific learning difficulties. Using a test of reading speed and a test of reading accuracy we have attempted to evaluate the device. Two groups of children with learning difficulties were used, one having sole use of the device and being allowed to carry it with them and a second group who only used the device when attending for remedial tuition and assessment. The results show that no significant improvement occurred in reading performance of the groups with learning difficulties using the Dex Frame as compared with a control group. The teachers of the groups did, however, feel that on an individual basis some children (< 10%) expressed that they felt more comfortable using the device. 相似文献
46.
47.
Francis Y. Yao MD 《Current hepatitis reports》2006,5(1):14-22
A new era in the treatment of chronic hepatitis B began approximately a decade ago. Three oral nucleoside or nucleotide analogues—lamivudine,
adefovir dipivoxil, and entecavir—are now approved in the United States for the treatment of chronic hepatitis B. Other new
oral agents, including telbivudine, clevudine, and emtricitabine, are in various stages of clinical investigation. This article
reviews the efficacy and resistance data of these oral antiviral agents, and the preliminary results of combination therapy
for chronic hepatitis B. 相似文献
48.
Virginia L Willour Peter P Zandi Judith A Badner Jo Steele Kuangyi Miao Victor Lopez Dean F MacKinnon Francis M Mondimore Barbara Schweizer Melvin G McInnis Erin B Miller J Raymond Depaulo Elliot S Gershon Francis J McMahon James B Potash 《Neuropsychopharmacology》2007,61(5):725-727
BACKGROUND: We are interested in identifying susceptibility genes that predispose subjects to attempted suicide. METHODS: We conducted a secondary analysis of genome-wide linkage data from 162 bipolar pedigrees that incorporated attempted suicide as a clinical covariate. RESULTS: The strongest covariate-based linkage signal was seen on 2p12 at marker D2S1777. The logarithm of odds (LOD) score at marker D2S1777 rose from 1.56 to 3.82 after inclusion of the suicide covariate, resulting in significant chromosome-wide empirically derived p-values for the overall linkage finding (p = .01) and for the change in LOD score after the inclusion of the covariate (p = .02). CONCLUSIONS: The finding on chromosome 2 replicates results from two previous studies of attempted suicide in pedigrees with alcohol dependence and in pedigrees with recurrent early-onset depression. Combined, these three studies provide compelling evidence for a locus influencing attempted suicide on 2p12. 相似文献
49.
50.
Monitoring the protective effects of minocycline treatment with radiolabeled annexin V in an experimental model of focal cerebral ischemia. 总被引:3,自引:0,他引:3
Xian Nan Tang Qing Wang Maya A Koike Danye Cheng Michael L Goris Francis G Blankenberg Midori A Yenari 《Journal of nuclear medicine》2007,48(11):1822-1828
Minocycline is an antibiotic now recognized to have antiapoptotic and antiinflammatory properties. Because of these properties, minocycline may be of benefit in reducing neuronal apoptosis from ischemia and subsequent postischemic inflammation if administered soon after a stroke. We now explore the feasibility of using (99m)Tc-annexin V, an in vivo marker of apoptosis, with SPECT to monitor the antiapoptotic effects of minocycline therapy. METHODS: CB6/F1 adult male mice underwent unilateral distal middle cerebral artery occlusion (dMCA) occlusion and were imaged and sacrificed at 1, 3, 7, or 30 d after injury. Animals were given minocycline (or vehicle) 30 min and 12 h after dMCA occlusion and then given 22.5 mg/kg twice daily for up to 7 d. Before imaging, behavioral tests were performed to evaluate the neurologic function. After imaging, brains were collected for histology and assessed for the degree of apoptosis and microglial activation. RESULTS: (99m)Tc-Annexin V uptake in injured hemispheres was significantly decreased 2- to 3-fold by minocycline at all time points. Minocyline reduced infarct size as seen histologically and improved behavioral indices as late as 30 d. Infarct volume as seen histologically correlated with radiolabeled annexin V uptake seen by SPECT. In situ fluorescent microscopy demonstrated that annexin V bound primarily to neurons at 1 and 3 d, with a shift toward microglia by 7 and 30 d. CONCLUSION: We found that minocycline significantly reduces neuronal apoptosis and infarct size and improves neurologic outcome in mice after acute focal cortical ischemia. 相似文献