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MA Rafferty AD Hill AP Zbar SG Shering M Lucey EW McDermott NJ O'Higgins 《Canadian Metallurgical Quarterly》1997,90(5):188-189
Parathyroidectomy should be considered in every patient with hypercalcaemia and primary hyperparathyroidism even if the symptoms are vague. Cervical exploration is a safe operation with very satisfactory results. Our experience in 214 patients over 25 years shows permanent postoperative normocalcaemia in 95% of cases with a complication rate of 2.8%. All patients with primary HPT, regardless of age or the severity of symptoms should be candidates for cervical exploration. 相似文献
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A 17-amino acid arginine-rich peptide from the bovine immunodeficiency virus Tat protein has been shown to bind with high affinity and specificity to bovine immunodeficiency virus transactivation response element (TAR) RNA, making contacts in the RNA major groove near a bulge. We show that, as in other peptide-RNA complexes, arginine and threonine side chains make important contributions to binding but, unexpectedly, that one isoleucine and three glycine residues also are critical. The isoleucine side chain may intercalate into a hydrophobic pocket in the RNA. Glycine residues may allow the peptide to bind deeply within the RNA major groove and may help determine the conformation of the peptide. Similar features have been observed in protein-DNA and drug-DNA complexes in the DNA minor groove, including hydrophobic interactions and binding deep within the groove, suggesting that the major groove of RNA and minor groove of DNA may share some common recognition features. 相似文献
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AD Vellet J Saliken B Donnelly E Raber RF McLaughlin D Wiseman NH Ali-Ridha 《Canadian Metallurgical Quarterly》1997,203(3):653-659
PURPOSE: To evaluate the usefulness of contrast material-enhanced magnetic resonance (MR) imaging in objective assessment of prostatic cryosurgery and the role of MR imaging in the modification of prostatic cryosurgical technique. MATERIALS AND METHODS: Thirty-eight consecutive patients with localized (T1-3, N0, M0) prostatic adenocarcinoma treated with prostatic cryosurgery underwent MR imaging without contrast enhancement before cryosurgery and unenhanced and gadolinium-enhanced MR imaging within 1-3 weeks after cryosurgery. The first 20 patients also underwent MR imaging at 3 months after cryosurgery. MR imaging findings were correlated with those from transrectal ultrasound-directed prostatic staging biopsy. RESULTS: Cryonecrotic prostate was identified as avascular regions characterized by absolute signal void on contrast-enhanced images. With progressive modification of cryosurgical technique, complete cryoablation of the prostate was achieved in the latter nine of the 38 patients. When cryoablation was considered complete according to MR imaging criteria, findings invariably correlated with those at biopsy, with no residual prostate tissue or tumor. CONCLUSION: Gadolinium-enhanced MR imaging of the prostate after cryosurgery provides a highly accurate means of monitoring success. Objective MR imaging findings allow modifications to the technology and technique, resulting in optimal therapeutic results with prostatic cryosurgery. 相似文献