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71.
Tomas Norlander Sam-Hyun Kwon Gert Henriksson Karl Magnus Westrin Karin Sandstedt Pontus Stierna 《The Laryngoscope》1998,108(3):411-417
To investigate possible effects of corticosteroids on polyp formation and local bacterial colonization, pneumococcal sinusitis was experimentally induced in rabbits pretreated with betamethasone or saline. After 7 days, macroscopic polyps were counted post-mortem and on histologic slides after serial sectioning. Histologic sections were also examined with light microscopy. Macroscopic polyps were significantly fewer in animals given betamethasone, while there was no difference regarding the number of microscopic polyps. Ingrowth of pathogenic microorganisms was found in five of eight rabbits given placebo but in none of the animals treated with corticosteroids (P < 0.05). The reduced number of pathogenic strains in these animals may be explained by a better-preserved local host defense. The lower number of macroscopic polyps in the same animals could be because of a delayed mucosal repair and subsequent polyp formation. 相似文献
72.
Ilona Kryspin S rensen Eva Kristiansen Alicja Mortensen Gert M. Nicolaisen Jolanda A. H. Wijnands Henk J. van Kranen Coen F. van Kreijl 《Cancer letters》1998,130(1-2):217-225
Data from epidemiological studies suggest that isoflavones in soy may have a protective effect on the development of colon cancer in humans. Therefore, we have investigated whether soy isoflavones will inhibit intestinal tumour development in ApcMin mice. The mice were fed a Western-type high risk diet (high fat, low fibre and calcium) containing two different isolates of soy protein as a protein source. For the control and test groups this resulted in the administration of about 16 and 475 mg of total isoflavones per kg diet, respectively. As a positive control, a third group of mice was administered a low isoflavone diet supplemented with 300 ppm sulindac. No significant differences in the incidence, multiplicity, size and distribution of intestinal tumours were observed between Min mice fed low and high isoflavone-containing diets. However, a clear reduction in the number of small intestinal tumours was observed for the sulindac diet. Thus, in contrast to epidemiological studies, our results demonstrate that high amounts of soy isoflavones present in a Western-type high risk diet do not protect against intestinal tumour development in a relevant animal model such as the Min mice. 相似文献
73.
Anna van Rhenen Nicole Feller Angèle Kelder August H Westra Elwin Rombouts Sonja Zweegman Marjolein A van der Pol Quinten Waisfisz Gert J Ossenkoppele Gerrit Jan Schuurhuis 《Clinical cancer research》2005,11(18):6520-6527
PURPOSE: In CD34-positive acute myeloid leukemia (AML), the leukemia-initiating event originates from the CD34(+)CD38(-) stem cell compartment. Survival of these cells after chemotherapy may lead to minimal residual disease (MRD) and subsequently to relapse. Therefore, the prognostic impact of stem cell frequency in CD34-positive AML was investigated. EXPERIMENTAL DESIGN: First, the leukemogenic potential of unpurified CD34(+)CD38(-) cells, present among other cells, was investigated in vivo using nonobese diabetic/severe combined immunodeficient mice transplantation experiments. Second, we analyzed whether the CD34(+)CD38(-) compartment at diagnosis correlates with MRD frequency after chemotherapy and clinical outcome in 92 AML patients. RESULTS: In vivo data showed that engraftment of AML blasts in nonobese diabetic/severe combined immunodeficient mice directly correlated with stem cell frequency of the graft. In patients, a high percentage of CD34(+)CD38(-) stem cells at diagnosis significantly correlated with a high MRD frequency, especially after the third course of chemotherapy. Also, it directly correlated with poor survival. In contrast, total CD34(+) percentage showed no such correlations. CONCLUSIONS: Both in vivo data, as well as the correlation studies, show that AML stem cell frequency at diagnosis offers a new prognostic factor. From our data, it is tempting to hypothesize that a large CD34(+)CD38(-) population at diagnosis reflects a higher percentage of chemotherapy-resistant cells that will lead to the outgrowth of MRD, thereby affecting clinical outcome. Ultimately, future therapies should be directed toward malignant stem cells. 相似文献
74.
Tumor lymphangiogenesis in inflammatory breast carcinoma: a histomorphometric study. 总被引:11,自引:0,他引:11
Ilse Van der Auwera Gert G Van den Eynden Cecile G Colpaert Steven J Van Laere Peter van Dam Eric A Van Marck Luc Y Dirix Peter B Vermeulen 《Clinical cancer research》2005,11(21):7637-7642
PURPOSE: At the time of diagnosis, metastatic dissemination of tumor cells via the lymphatic system has occurred in nearly all patients with inflammatory breast cancer (IBC). The objective of this study was twofold: (a) to determine which is the most suitable marker of lymph vessels in primary breast tumors and (b) to compare histomorphometric lymph vessel variables in IBC and non-IBC. EXPERIMENTAL DESIGN: Serial sections of 10 IBCs and 10 non-IBCs were immunostained for D2-40, LYVE-1, podoplanin, and PROX-1. Relative lymph vessel area, lymph vessel perimeters, and counts and lymphatic endothelial cell proliferation (LECP) were then measured in D2-40/Ki-67 double-immunostained sections of 10 normal breast tissues, 29 IBCs, and 56 non-IBCs. RESULTS: D2-40 was the most suitable antibody for staining peritumoral and intratumoral lymph vessels. D2-40-stained intratumoral lymph vessels were present in 80% of non-IBCs and 82.8% of IBCs (P = 0.76). In non-IBC, lymph vessels located in the tumor parenchyma were smaller and less numerous than those at the tumor periphery (P < 0.0001) whereas in IBC, intratumoral and peritumoral variables were not significantly different. The mean relative tumor area occupied by lymph vessels was larger in IBC than in non-IBC (P = 0.01). LECP at the tumor periphery was higher in IBC than in non-IBC: median LECP was 5.74% in IBC versus 1.83% in non-IBC (P = 0.005). CONCLUSIONS: The high LECP in IBC suggests that lymphangiogenesis contributes to the extensive lymphatic spread of IBC. 相似文献
75.
It has been argued in previous issues of this journal that health technology assessment can be used as a tool to assess the efficiency of pharmaceutical care by linking its impact on clinical and humanistic outcomes to the resources required to achieve these outcomes. Additionally, as policy-makers appreciate the need to evaluate projects on the basis of their costs and benefits, the application of health technology assessment to pharmaceutical care may serve as a way of communicating with policy-makers and informing policy on pharmaceutical care.This article elaborates on this idea by arguing that policy-makers will be more likely to appreciate the value of pharmaceutical care if researchers pay more attention to some methodological principles underlying health technology assessment in the context of pharmaceutical care, and if they take into account the decision-making context facing policy-makers. In order to raise the methodological quality of studies, researchers need to take care to define better the pharmaceutical care intervention; to evaluate the costs of the intervention and its impact on the utilization of other health services; and to aggregate the various clinical and humanistic outcome measures that are commonly used in this type of research. In order to increase the usefulness of study findings to policy-makers, researchers need to identify the multiple objectives that policy-makers pursue, and show how study findings will aid policy-makers in attaining these objectives. 相似文献
76.
Health promotion (HP) amongst older people is an increasingly prominent policy concern for governments. The development of an evidence-base and the advocacy of effective interventions in the light of this act as legitimation tools for the overall HP phenomenon – assisting the growth of state and non-state funding for public health initiatives for older people. In structuring decision-making as to which individual projects/initiatives receive funding, frameworks for acknowledging efficacy impact on formats of HP work both positively and negatively. Drawing on recent research across the EU and focusing on the specific national contexts of Austria and England, this comparative policy analysis triangulates best-practice modelling, evaluation data and interviews with project coordinators to explore how policy contexts impact on the nature and format of HP interventions. Amidst a developing awareness of what effective practice looks like, successful HP initiatives must advocate their legitimacy within narrow rules of quality, where measurable outcomes have become the keys which unlock financial resources. Findings across both countries suggest that this instrumentalisation of legitimation, driven by economic pressures and bureaucratic generalisability, threatens the rationality of HP. From a Habermasian perspective, tensions emerge between projects’ remaining reflexive towards processes and their need to articulate the ‘success’ of the interventions in a language of outcomes. Over time, in an era where resources are increasingly scarce and competition over these intensifies, a danger exists whereby the instrumentality of HP begins to separate from, and impinge upon, the capacity for projects to think and act holistically. 相似文献
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