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排序方式: 共有1390条查询结果,搜索用时 15 毫秒
991.
Utility of serum ferritin as a measure of iron deficiency in normal males undergoing repetitive phlebotomy 总被引:1,自引:0,他引:1
Hematologic indices and iron balance data were obtained on 22 normal male volunteers who were subjected to a mean +/- SD phlebotomy of 164 +/- 34 ml whole blood/mo while living in a controlled environment. Over an average stay of 5 mo, volunteers did not develop anemia, but did display a reduction in iron stores that was quantitated by measurement of serum ferritin and iron balance. The percent saturation of transferrin and the usual erythrocyte parameters did not reflect changes in iron status. Loss of iron, which was calculated from quantitative phlebotomy and iron balance data, showed that a decrease of 1 ng of serum ferritin represented a loss of 4.5 +/- 5.3 mg of iron in 10 men whose initial serum ferritins were greater than 25 ng/ml, and 25.3 +/- 58.8 mg of iron in 7 men whose initial serum ferritins were less than 25 ng/ml. The period required for 3 volunteers who consumed a self-selected mixed diet at home to replace their depleted iron stores to prephlebotomy levels was about 4.5 mo. The sensitivity of serum ferritin as an index of iron stores was affirmed. In addition it was found that normal men who were consuming a mixed diet containing about 15 mg of iron daily and losing blood at a rate of 164 +/- 34 ml/mo did not increase their iron absorption sufficiently to compensate for the iron loss. 相似文献
992.
993.
Teplick SK; Haskin PH; Sammon JK; Clearfield HR; Borowsky LM; Gambescia RA; Zitomer N; Goldstein RC 《Radiology》1986,161(1):135-138
Percutaneous transcholecystic cholangiography was performed in 20 patients. Fifteen patients had normal-sized bile ducts on sonograms and computed tomographic scans, and five had partial common bile duct obstruction. Gallbladder pressures were measured in 14 patients. In all cases the intrahepatic and extrahepatic bile ducts were well visualized. Only one clinically significant complication, bile peritonitis, occurred, and it was relieved by inserting a cholecystostomy catheter. Techniques as well as the potential indications for transcholecystic cholangiography are discussed. The authors believe the transcholecystic approach is a useful alternative to transhepatic cholangiography. 相似文献
994.
Probable Alzheimer disease: diagnosis with proton MR spectroscopy 总被引:25,自引:0,他引:25
995.
996.
Dorfman GS; Cronan JJ; Paolella LP; Lambiase RE; Haas RA; Scola FH; Schepps B 《Radiology》1989,173(1):159-162
To determine the prevalence of iatrogenic abnormalities associated with percutaneous delivery of Greenfield filters, the authors prospectively evaluated 69 peripheral veins used for filter placement in 68 patients. Of the 69 venotomy sites, 63 were not associated with preexisting thrombosis and were evaluated with compression and Doppler ultrasound within 1 week of placement and over 13-541 days. New thrombosis developed at the puncture site in nine of 63 sites (14.3%), although clinical suspicion of clot was raised in only one patient. Fifty-four sites (85.7%) showed no evidence of acute deep venous thrombosis, even though three patients had signs and symptoms suggestive of thrombosis. During the follow-up, most new thromboses resolved, yielding a 96.3% long-term patency rate. The authors conclude that postplacement increase in symptoms of venous stasis and occlusion may not correlate with placement site thrombosis. New filters should be evaluated for their ability to capture potential pulmonary emboli while maintaining caval patency and for mechanical and biologic stability because placement site complications occur at low rates and resolve in most cases. 相似文献
997.
Atlas SW; Grossman RI; Axel L; Hackney DB; Bilaniuk LT; Goldberg HI; Zimmerman RA 《Radiology》1987,164(2):510-514
Thirteen orbital lesions in 12 patients were evaluated with both conventional spin-echo magnetic resonance (MR) imaging and phase-dependent proton spectroscopic imaging. This technique, which makes use of small differences in the resonant frequencies of water and fat protons, provides excellent high-resolution images with simultaneous chemical shift information. In this method, there is 180 degrees opposition of phase between fat protons and water protons at the time of the gradient echo, resulting in signal cancellation in voxels containing equal signals from fat and water. In this preliminary series, advantages of spectroscopic images in orbital lesions included better lesion delineation, with superior anatomic definition of orbital apex involvement; more specific characterization of high-intensity hemorrhage with a single pulse sequence; elimination of potential confusion from chemical shift misregistration artifact; further clarification of possible intravascular flow abnormalities; and improved apparent intralesional contrast. 相似文献
998.
Imaging the testis: comparison between MR imaging and US 总被引:1,自引:0,他引:1
The potential role of magnetic resonance (MR) imaging in the diagnosis and local staging of testicular tumors was evaluated in 23 patients who subsequently underwent surgery or biopsy. Findings at MR imaging were compared with those at ultrasonography (US) and were correlated with the surgical-histologic findings. At surgery, three patients were found to have extratesticular and 20 patients intratesticular abnormalities. This distinction had been correctly made with both imaging modalities, but US did not demonstrate the intratesticular abnormality in four patients with diffuse infiltrating tumors. Neither modality allowed differentiation of benign from malignant disorders. When local tumor staging was analyzed in 11 patients, the accuracy of both modalities was disappointing (true-positive findings with MR imaging in seven patients and with US in five). At present, US remains the primary imaging modality for testicular disease. MR imaging should be employed when findings at physical examination and US are discrepant and considered when diffuse infiltrative disease is suspected. 相似文献
999.
1000.
FM Buonaguro † ML Tornesello † L Buonaguro † RA Satriano § E Ruocco § G Castello ‡ V Ruocco§ 《Journal of the European Academy of Dermatology and Venereology》2003,17(2):138-154
Kaposi's sarcoma (KS) represents today one of the most common skin cancers in transplanted Mediterranean subjects and, since the epidemic of human immunodeficiency virus/acquired immune deficiency syndrome, in young unmarried single men. The disease has been associated with the recent identified human herpesvirus (HHV)-8 or KS herpesvirus and its incidence in the general population shows a north to south gradient that parallels the HHV-8 increasing prevalence from Nordic countries to sub-Saharan regions. The identification of the aetiopathogenetic mechanisms (viral agents and immunodeficiency) involved in the pathogenesis of KS, are relevant for identifying susceptible subjects (HHV-8 seropositive subjects), monitoring the immune levels in iatrogenic immune suppressed patients, and developing new therapeutic approaches based on antiviral and immune modulators. Learning objective: This article should enable the reader: (i) to learn about the clinical and molecular aspects of KS in order to have a multidisciplinary approach to a tumour that shows unique features; (ii) to consider the role of viral agents and immunity; and (iii) to recognize properties of an opportunistic neoplasm. The identification of the HHV-8 role in KS pathogenesis should establish a relevant tool in the clinical management of KS patients. 相似文献