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排序方式: 共有879条查询结果,搜索用时 31 毫秒
71.
72.
Carotid sinus hypersensitivity and the carotid sinus syndrome 总被引:4,自引:0,他引:4
B Strasberg A Sagie S Erdman J Kusniec S Sclarovsky J Agmon 《Progress in cardiovascular diseases》1989,31(5):379-391
73.
Soy products and the human diet 总被引:2,自引:0,他引:2
This review focuses upon the nutritional significance of soy products in the human diet. The impact of the consumption of soy foods on a range of diet and health issues are discussed, including protein quality and growth promoting effects of soy protein, allergies in children, hypocholesterolemic effects of soy protein and soy fiber, effects of soy products upon glucose tolerance, and the bioavailability of zinc and iron from soy foods. Recent research reports involving humans and relevant animal studies are reviewed. 相似文献
74.
Mammographic findings after breast cancer treatment with local excision and definitive irradiation 总被引:1,自引:0,他引:1
Following local excision and definitive irradiation of 163 breast cancers in 160 women, alterations in mammographic patterns were observed for up to 7 years. Skin thickening was observed in 96% of mammograms obtained within 1 year of completing therapy and was most pronounced in women treated with iridium implant, chemotherapy, or axillary dissection. In 76% of mammograms, alterations in the parenchymal pattern, including coarsening of stroma and increased breast density, were seen at 1 year. Neither skin nor parenchymal changes progressed after 1 year. Within 3 years of treatment the parenchymal density, which usually regressed, did not change in all patients. At 3 years skin thickness and the parenchymal pattern had returned to normal in less than 50% of the breasts of these women. Scars developed in approximately one-quarter of women. They were present on the initial post-treatment mammogram and remained unchanged on serial studies. Coarse, benign calcifications also developed in the breasts of about one-quarter of women. Microcalcifications developed in 11 breasts; biopsy specimens of six were benign. Benign microcalcifications may be related to therapy. 相似文献
75.
Lymphangiomas in children: MR imaging 总被引:9,自引:0,他引:9
Seventeen lymphangiomas in 15 patients were imaged with magnetic resonance (MR) to define the nature, extent, and anatomic relationships of these lesions. The MR and pathologic findings were then compared to determine the histologic basis for the signal-intensity characteristics of these lesions. The signal intensity of 13 lesions was similar to or slightly less than that of muscle on T1-weighted images and greater than that of fat on T2-weighted images. This appearance correlated with the presence of ectatic lymphatic channels containing clear fluid on histologic section. Four lymphangiomas had high signal intensity, approximately equal to that of fat, on T1-weighted images, reflecting the presence of clotted blood or small cystic spaces with a higher ratio of fat to fluid. Sixteen of 17 lesions had visible septations on MR images. The authors' experience suggests that most lymphangiomas have a characteristic appearance on MR images. The information obtained with MR imaging can help in providing a preoperative diagnosis, in planning surgical resection, and in defining recurrence. 相似文献
76.
This article updates the previous review in the Journal regarding theophylline dosing methods. Among the predictive algorithms evaluated, the dose-titration scheme of Weinberger and Hendeles was extensively tested in 1073 asthmatic patients. When the scheme was followed appropriately, 78% of initial serum concentrations and 66% of repeat serum concentrations were within the therapeutic range of 10 to 20 mg/L. Several authors have also demonstrated that the 'condition correction factor' method for estimating theophylline clearance is of limited value. The individualised methods of Chiou, Koup and Vozeh have been evaluated in over 300 patients. In addition, numerous authors have reported the relative predictive performance of Bayesian dosing programs for theophylline. All methods continue to be a rapid and accurate means of individualizing dosing requirements for patients with a diverse range of theophylline disposition characteristics. Overall, the Bayesian predictions have been less biased and slightly more precise than the pharmacokinetics-based dosing methods. The most recent cost-effectiveness data has shown that a pharmacokinetic dosing program resulted in fewer toxic serum concentrations (18.9% vs 37.8%), a shorter mean duration of hospital stay (6.3 vs 8.7 days) and more therapeutic concentrations with subsequent oral therapy (71.1% vs 44.4%) than among control patients receiving dosages prescribed by physicians. 相似文献
77.
Liver metastases: detection by phase-contrast MR imaging 总被引:1,自引:0,他引:1
Forty patients with biopsy-proved metastatic liver cancers were studied by magnetic resonance (MR) imaging using one or more conventional (in-phase) pulse sequences and a corresponding phase-contrast (opposed-phase) pulse sequence. Pulse-sequence performance was quantitated by measuring signal-difference-to-noise (SD/N) ratios between cancerous tissue and liver. The SD/N performance of T2-weighted spin-echo (SE) pulse sequences improved when used with the phase-contrast technique. SE 2,000/30 opposed-phase images showed improved (P less than .001) SD/N in 72% of patients over in-phase images. The SD/N of T1-weighted SE or inversion recovery pulse sequences deteriorated when used with the phase-contrast technique. Changes in measured SD/N correlated well with image appearance and actual lesion detectability in individual cases. Phase-contrast imaging should be employed routinely when T2-weighted SE pulse sequences are relied on to detect liver cancer. 相似文献
78.
Vallbracht C; Liermann DD; Prignitz I; Beinborn W; Roth FJ; Kollath J; Landgraf H; Kaltenbach M 《Radiology》1989,172(2):327-330
Between December 1986 and October 1988, 83 patients with chronic peripheral artery occlusions were treated with a new technique. In 56 patients, the superficial femoral artery was completely occluded; in 21 patients, the popliteal artery; and in six patients, the iliac artery. The length of occlusion ranged from 5 to 35 cm (mean, 12.5 cm). The duration, estimated by history, was 5-48 months (mean, 16.5 months). In seven patients, durations of 6-36 months were documented angiographically. A flexible, blunt, motor-driven rotating catheter was introduced through an 8-F sheath, and rotational angioplasty was performed at low speed (up to 200 rpm). In 49 of 60 (82%) patients in whom this new technique was used as the primary intervention, the occlusions were successfully reopened. In 23 patients in whom conventional methods had failed more than 4 weeks earlier, the success rate for rotational angioplasty was 67% (12 of 18 patients); when the time interval was less than 4 weeks, only one of five patients was treated successfully. In none of the 83 patients did a perforation occur. This new technique can reopen chronic artery occlusions with a high degree of success and without the danger of vessel-wall perforation, even after failure of conventional techniques. 相似文献
79.
80.
H P Erdman J H Greist D H Gustafson J E Taves M H Klein 《The Journal of clinical psychiatry》1987,48(12):464-467
A computer interview program that uses a subjective Bayesian probability model to assess suicide risk was evaluated. Predictions made by clinicians for 52 patients were compared with predictions made by the computer for the same patients. The computer was significantly (p = .001) better at predicting attempters, and clinicians were significantly (p = .01) better at predicting nonattempters. An analysis of receiver operating characteristic curves showed that the computer had better overall discrimination, but the difference was nonsignificant. 相似文献