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91.
92.
Yekaterina Y Zaytseva Xin Wang R Chase Southard Natalie K Wallis Michael W Kilgore 《Molecular cancer》2008,7(1):90
Background
Peroxisome proliferator-activated receptor gamma (PPARγ) is a member of the nuclear hormone receptor superfamily and is highly expressed in many human tumors including breast cancer. PPARγ has been identified as a potential target for breast cancer therapy based on the fact that its activation by synthetic ligands affects the differentiation, proliferation, and apoptosis of cancer cells. However, the controversial nature of current studies and disappointing results from clinical trials raise questions about the contribution of PPARγ signaling in breast cancer development in the absence of stimulation by exogenous ligands. Recent reports from both in vitro and in vivo studies are inconsistent and suggest that endogenous activation of PPARγ plays a much more complex role in initiation and progression of cancer than previously thought. 相似文献93.
94.
Smith P Masterson A Basford L Boddy G Costello S Marvell G Redding M Wallis B 《Nurse education today》2000,20(7):563-570
This paper arose from a research study and its follow-up in four schools of nursing and midwifery. The study was concerned with evaluating the extent to which a philosophy of health had been integrated into the educational curricula of nurses, midwives and health visitors. The purpose of the follow-up was to disseminate and implement the study findings in the four centres. The findings showed that the interpretation and implementation of a philosophy of health in nursing had been variable. Health was operationalized as both health education and health promotion ranging from individualized information giving and disease prevention. Action research was chosen as the appropriate methodology for the follow-up because of its emphasis on participation and partnership. As the follow-up study progressed a number of issues emerged which were indicative of the changes taking place in nurse education as its institutional base shifted into higher education. Other issues were associated with the gap between the rhetoric and reality of action research and the expectations and needs of the key partners. The authors conclude that the follow-up study presented both challenges and opportunities to nurse educators in their endeavour to undertaken research and implement educational change. 相似文献
95.
Host adapted serotypes of Salmonella enterica 总被引:1,自引:0,他引:1
Uzzau S Brown DJ Wallis T Rubino S Leori G Bernard S Casadesús J Platt DJ Olsen JE 《Epidemiology and infection》2000,125(2):229-255
96.
Cyanosis, clubbing, and arterial oxygen desaturation may occur in patients with liver disease, and are attributed to the presence of pulmonary or peripheral arterio-venous shunting. Cardiac catheterisation and angiocardiography in a patient with a normal heart did not demonstrate the presence of abnormal arterio-venous anastomoses. Pulmonary shunting was proved when intravenous technetium-labelled macroaggregated albumin, normally held up in capillary networks, was passed quickly through the lungs and immediately detected in high systemic blood flow organs. The opening of peripheral and pulmonary anastomoses in patients with liver disease may be owing to the presence of a vasodilatory substance such as ferritin, which was found to be abnormally increased in the patient's blood. 相似文献
97.
98.
Bush A Wallis C 《American journal of respiratory and critical care medicine》2003,167(11):1577; author reply 1577-1577; author reply 1578
99.
Posttransplant lymphoproliferative disorders in liver transplantation: a 20-year experience 总被引:10,自引:0,他引:10
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Jain A Nalesnik M Reyes J Pokharna R Mazariegos G Green M Eghtesad B Marsh W Cacciarelli T Fontes P Abu-Elmagd K Sindhi R Demetris J Fung J 《Annals of surgery》2002,236(4):429-437
OBJECTIVE: To evaluate the incidence of posttransplant lymphoproliferative disease (PTLD) and the risk factors and the impact of this complication on survival outcomes in a large cohort of liver transplant recipients at a single institution. SUMMARY BACKGROUND DATA: Liver transplantation has been accepted as a therapeutic option for patients with end-stage liver disease since 1983, in large part due to the availability and reliance on the use of nonspecifically directed immunosuppression. However, as predicted and subsequently verified in 1968, an increased incidence of certain de novo malignancies has been observed, particularly with regards to lymphoid neoplasms. While many reports have confirmed and clarified the nature of PTLD, the literature is fraught with conflicting experience and outcomes with PTLD. METHODS: Four thousand consecutive patients who underwent liver transplants between February 1981 and April 1998 were included in this analysis and were followed to November 2001. The effect of recipient age at the time of transplant, recipient gender, diagnosis, baseline immunosuppression, grading of PTLD, and association with Epstein-Barr virus were compared. The causes of death were also examined. Treatment for PTLD varied over the 20-year period, but all included massive reduction or elimination of baseline immunosuppression. RESULTS: The 1-year patient survival for liver transplant patients with PTLD was 85%, while the overall patient survival for the entire cohort was 53%. The actuarial 20-year survival was estimated at 45%. The overall median time to PTLD presentation was 10 months, and children had an incidence of PTLD that was threefold higher than adults. Patient survival was better in children, in patients transplanted in the era of tacrolimus immunosuppression, in patients with polymorphic PTLD, and in those with limited disease. Interestingly, neither the presence or absence of Epstein-Barr virus nor the timing of PTLD presentation appeared to influence overall patient survival. Patients transplanted for alcohol-related liver disease had a similar incidence of PTLD but had a higher risk of mortality. CONCLUSIONS: While PTLD continues to pose problems in patients receiving liver transplants, improvements in patient survival have been observed over time. While it is too early to assess the impact of new advances in prophylaxis, diagnosis, and treatment, such approaches are based on an increased knowledge of the pathophysiology of PTLD. 相似文献
100.
Magnetic resonance imaging appearances of the uterus following microwave endometrial ablation 总被引:2,自引:0,他引:2
AIM: Microwave endometrial ablation (MEA) is a treatment for dysfunctional uterine bleeding. It is a second generation ablative technique which is as effective as hysteroscopic methods but quicker and easier to perform. Our aim is to describe the Magnetic Resonance Imaging (MRI) appearances of the uterus following this procedure. METHODS: 15 women underwent MRI immediately before MEA, and again at one day and 4 months after treatment. T1 and T2 sequences were performed at 1.0T using a body coil. Images were assessed by 2 independent observers for quantitative and qualitative changes. Clinical questionnaires were completed before treatment and at 4 months. RESULTS: On images obtained one day post-ablation, 14 patients had a low signal intensity band subjacent to the treated area of the endometrial cavity on T2 images. Imaging at 4 months showed significant amounts of endometrial tissue in 11 patients, including 3 of the 6 patients who were amenorrhoeic. There were no changes in the appearances of myometrium or uterine dimensions and there were no haematometra. CONCLUSIONS: The detection of residual endometrium by MRI means that unopposed oestrogen hormone replacement therapy should be avoided after MEA, even in women who have amenorrhoea. Thepost-operative sub-endometrial low signal intensity zone corresponds to the region of tissue necrosis detected on vital staining of the treated uterus in in vivotesting. Depth of tissue destruction is a surrogate marker for clinical effectiveness. MRI may have a role in early assessment of patients participating in clinical research who are undergoing a modified MEA technique while retaining their uterus. 相似文献