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We have determined the frequency of heterozygosity of the short arm of chromosome 17 in 20 cervical tumours using the highly polymorphic probe pYNZ22. Only 25% of the tumours were heterozygous at this locus. This is significantly lower than the level of 86% heterozygosity for this locus in the general population indicating that loss of one allele occurs in cervical cancer. Heterozygosity for a locus on the long arm of the same chromosome showed no significant difference between the tumours and the general population indicating that genetic loss was confined to the short arm of the chromosome. The analysis of premalignant lesions showed 70% of patients were heterozygous suggesting that loss of material from the short arm of chromosome 17 took place at a late stage in tumour development. This report confirms predictions made from previous karyotypic analysis and is the first indication of allele loss on the short arm of chromosome 17 in cervical cancer. 相似文献
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Boyle M; Gawley W; Hickey D; Drumm J; Murphy D; Hanson J; Glacken P 《Nephrology, dialysis, transplantation》1997,12(9):1934-1939
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Regional gene therapy for full-thickness articular cartilage lesions using naked DNA with a collagen matrix. 总被引:3,自引:0,他引:3
Paul E Di Cesare Sally R Frenkel Cathy S Carlson Carrie Fang Chuanju Liu 《Journal of orthopaedic research》2006,24(5):1118-1127
A novel gene therapy approach for treating damaged cartilage is proposed that involves placing endotoxin-free cDNA containing the gene for bone morphogenetic protein-2 (BMP-2) in type I collagen sponges and then transferring the naked plasmid DNA construct to the injury site. A full-thickness cartilaginous defect in rabbits implanted with plasmid containing a marker gene (beta-galactosidase) showed expressed protein as detected by immunostaining. At 1 week postimplantation, mesenchymal cells subjacent to the defect had incorporated the implanted naked plasmid DNA and, once transfected, served as local bioreactors, transiently producing the gene product. Plasmids containing the gene for BMP-2 implanted in collagen sponges in cartilage lesions stimulated hyalinelike articular cartilage repair at 12 weeks postimplantation, nearly equivalent in quality to that induced by collagen sponges with recombinant BMP-2 protein. Our approach circumvents the risks of inflammation and immunogenic response associated with the use of viral vectors. Naked plasmid DNA as a vehicle for transferring therapeutic genes has been shown to be effective in a therapeutic model within rabbit articular cartilage and appears to be safe and cost effective. 相似文献
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Margaret J. Harrison Kaysi Eastlick Kushner Karen Benzies Gwen Rempel Cathy Kimak 《分娩》2003,30(2):109-115
ABSTRACT: Background: Increasingly, women seek involvement in decisions about their health care. The purpose of this study was to examine women's experience of, and satisfaction with, their involvement in health care decisions during a high‐risk pregnancy. Methods: Forty‐seven women with hypertension or threatened preterm delivery (including multiple births) were interviewed after the birth of their child. They received prenatal care at home from nurses in a community program or were hospitalized. The in‐depth interviews were audiotaped and transcribed; data were analyzed using constant comparative methods. Results: Women identified an increased feeling of responsibility for the health of their baby and themselves, but differed in choosing active or passive involvement in health care decisions. Women who wanted active involvement achieved it through one of three processes: struggling for, negotiating, or being encouraged. Women who wanted passive involvement and women facing health crises used the process of trusting in the expertise of nurses and physicians. Women were satisfied if the care from health care professionals was congruent with how they wanted to be involved in decision‐making. Conclusions: Although most women want to be actively involved in health decision‐making during a high‐risk pregnancy, some prefer a passive role. The setting of prenatal care, community‐based or in‐hospital, was less important than the ability of nurses and physicians to support the woman in her preferred role in decision‐making. (BIRTH 30:2 June 2003) 相似文献
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Dawn Stacey RN MScN CON Annette M. O'Connor RN PhD † Cathy DeGrasse RN MScN ‡ Shailendra Verma MD FRCP § 《Health expectations》2003,6(1):3-18
Objective To develop and evaluate the effectiveness of a breast cancer prevention decision aid for women aged 50 and older at higher risk of breast cancer. Design Pre‐test–post‐test study using decision aid alone and in combination with counselling. Setting Breast Cancer Risk Assessment Clinic. Participants Twenty‐seven women aged 50–69 with 1.66% or higher 5‐year risk of breast cancer. Intervention Self‐administered breast cancer prevention decision aid. Main outcome measures Acceptability; decisional conflict; knowledge; realistic expectations; choice predisposition; intention to improve life‐style practices; psychological distress; and satisfaction with preparation for consultation. Results The decision aid alone, or in combination with counselling, decreased some dimensions of decisional conflict, increased knowledge (P < 0.01), and created more realistic expectations (P < 0.01). The aid in combination with counselling, significantly reduced decisional conflict (P < 0.01) and psychological distress (P < 0.02), helped the uncertain become certain (P < 0.02), and increased intentions to adopt healthier life‐style practices (P < 0.03). Women rated the aid as acceptable, and both women and practitioners were satisfied with the effect it had on the counselling session. Conclusion The decision aid shows promise as a useful decision support tool. Further research should compare the effect of the decision aid in combination with counselling to counselling alone. 相似文献
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Long H. Phan Michael J. Hickey Zahid B. M. Niazi Alastair G. Stewart 《Microsurgery》1994,15(10):703-707
Nitric oxide (NO), originally identified as the mediator of endothelial-dependent relaxation of vascular smooth muscle, is now known to also have cytotoxic effects under certain conditions. Thus, we have investigated the effects of inhibition of NO synthesis on ischemia/reperfusion injury in the rabbit rectus femoris muscle. Three and a half hours of ischemia and 24 hours of reperfusion resulted in a 56% loss of viability. In muscles receiving an infusion of the nitric oxide synthase inhibitor, L-NIO (30 μM), the loss of viability was reduced to 15%. Post-ischemic blood flow was increased in muscles receiving a saline infusion, whereas there was a marked decrease in blood flow for at least the first 60 minutes of reperfusion in muscles treated with L-NIO (30 μM). The increase in myeloperoxidase levels (indicative of neutrophil accumulation) following 24 hours of reperfusion was attenuated with L-NIO infusion by approximately 50% and the reperfusion-induced edema was also attenuated in L-NIO treated muscle. These findings suggest that endogenous NO production during ischemia/reperfusion injury may be deleterious to muscle survival. © 1994 Wiley-Liss, Inc. 相似文献