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681.
682.
EF Bernstein RB Dilley WS Thomas HF Randolph HJ Knowles M Saeed 《Canadian Metallurgical Quarterly》1994,8(2):186-194
The development of interventional radiologic techniques during the past decade has changed our approach to the treatment of lower extremity peripheral arterial disease (LE-PAD). Balloon and laser-assisted angioplasty, atherectomy (rotary and directional devices), stent implantation, and thrombolysis as well as combinations of all of these approaches, at times with concomitant or secondary surgery, have been used in our institution. A review of our practice patterns during the past 5 years was performed to analyze changing attitudes and results with these newer techniques. All new patients seen in consultation for LE-PAD during three alternate years were reviewed with regard to demographics, initial complaints, initial treatment modality, initial outcome, indications for and results of secondary treatment, and ultimate outcome (at 1 year). The 603 patients were seen during the following three 12-month periods: 1987 to 1988, 1989 to 1990, and 1991 to 1992. An intention-to-treat analysis revealed (1) the number of patients seen for peripheral arterial disease has increased steadily; (2) in the last year more were initially treated with intervention as the primary modality; (3) the results of such catheter-based procedures improved only slightly over this 5-year period, despite our learning curve and the fact that we discarded several ineffective interventional approaches; (4) the fraction of patients primarily operated on and the excellent results of surgery have not changed; and (5) the number of operations for proximal (aortoiliac) disease has decreased markedly, with a corresponding increase in distal reconstructions. The evolution of our current approach to the treatment of LE-PAD is based on this continuing experience. 相似文献
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The development of transplant atherosclerosis, a manifestation of chronic rejection, is the major obstacle to long-term survival of cardiac and renal allografts. The incidence of transplant atherosclerosis is increased in transplant recipients producing antidonor HLA antibodies following transplantation, suggesting that anti-HLA antibodies play a role in the pathogenesis of the disease. We have postulated that anti-HLA antibodies mediate the development of transplant atherosclerosis by binding to class I molecules on the endothelium and smooth muscle of the graft and transducing signals which stimulate cell proliferation. In this report we demonstrate that anti-HLA class I antibodies transduce signals in smooth muscle cells stimulating increased tyrosine phosphorylation of intracellular proteins and up-regulation of fibroblast growth factor (FGF) receptors. Antibody binding to class I molecules on smooth muscle cells is also accompanied by increased responsiveness to basic FGF and augmented cell proliferation. These findings may explain the increased occurrence of transplant atherosclerosis in recipients producing anti-donor HLA antibodies. 相似文献
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MJ van Dongen MM Mooren EF Willems GA van der Marel JH van Boom SS Wijmenga CW Hilbers 《Canadian Metallurgical Quarterly》1997,25(8):1537-1547
The three-dimensional structure of the hairpin formed by d(ATCCTA-GTTA-TAGGAT) has been determined by means of two-dimensional NMR studies, distance geometry and molecular dynamics calculations. The first and the last residues of the tetraloop of this hairpin form a sheared G-A base pair on top of the six Watson-Crick base pairs in the stem. The glycosidic torsion angles of the guanine and adenine residues in the G-A base pair reside in the anti and high- anti domain ( approximately -60 degrees ) respectively. Several dihedral angles in the loop adopt non-standard values to accommodate this base pair. The first and second residue in the loop are stacked in a more or less normal helical fashion; the fourth loop residue also stacks upon the stem, while the third residue is directed away from the loop region. The loop structure can be classified as a so-called type-I loop, in which the bases at the 5'-end of the loop stack in a continuous fashion. In this situation, loop stability is unlikely to depend heavily on the nature of the unpaired bases in the loop. Moreover, the present study indicates that the influence of the polarity of a closing A.T pair is much less significant than that of a closing C.G base pair. 相似文献
689.
MB Dahl B H?lund B S?rensen S Ahrons P Grinsted EF Poulsen 《Canadian Metallurgical Quarterly》1998,160(40):5798-5801
The outcome of screening for cervical cancer in the county of Funen was evaluated in two sequential periods (1.7.-31.12.1989 and 1.7.-31.12.1992), comprising 17,493 and 18,135 respectively. About 10.5% of the screened women had a define non-negative smear. From the first and the second period 80% and 85.1% of the non-negative smears respectively were followed up within six months. The follow-up of positive smears was 96% in both periods. Four point nine percent and 3.3% respectively of the non-negative smears were not followed up within 18 months. No women were actually lost in the screening system, unless they renounced further follow-up themselves. The follow-up was improved from the first to the second period, presumably as a result of a better general acquaintance with the screening procedures. The study indicates that reorganization of a screening programme requires both time and adjustment. Moreover, it is important that a successful screening programme frequently adjusts its procedures. 相似文献
690.
EF Magann SP Chauhan BG Nevils MF McNamara MJ Kinsella JC Morrison 《Canadian Metallurgical Quarterly》1998,178(6):1279-1287
OBJECTIVE: Our purpose was to determine the optimal management of pregnancies beyond 41 weeks' gestation with a cervix unfavorable for induction. STUDY DESIGN: All uncomplicated pregnancies that reached 41 weeks' gestation with a Bishop score of < or = 4 were randomly assigned to one of three groups: (1) daily cervical examinations, (2) daily membrane stripping, or (3) daily placement of prostaglandin gel until 42 weeks. RESULTS: In 105 pregnancies the Bishop score on admission to labor and delivery was significantly greater in the groups receiving prostaglandin or stripping of the membranes versus the control group, whereas the converse was time of gestational age at delivery (p = 0.0001). Fewer patients required induction in the two treatment groups (20%, 17%) versus the control (69%) patients (p < 0.0001). CONCLUSIONS: Daily membrane stripping or daily placement of prostaglandin gel is successful in reducing the number of inductions at 42 weeks for postdatism. 相似文献