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61.
Antagonism of arachidonic acid is linked to the antitumorigenic effect of dietary eicosapentaenoic acid in Apc(Min/+) mice 总被引:1,自引:0,他引:1
The multiple intestinal neoplasia (Apc(Min/+)) mouse possesses a germline mutation at codon 850 of the adenomatous polyposis coli (Apc) gene resulting in the formation of a nonfunctional truncated gene product. Following a somatic mutation of the remaining wild-type allele, mice spontaneously develop approximately 40-50 tumors throughout the intestinal tract. This mouse model has been used to study intestinal tumorigenesis because this mutation is analogous to the inherited APC mutation in humans with familial adenomatous polyposis (FAP). These individuals characteristically develop numerous adenomas throughout their intestinal tracts. Only a few studies have evaluated the effects of dietary fatty acids on tumorigenesis in this animal model with varying results, and none have linked these effects to alterations in arachidonic acid (AA) metabolism. This study was designed to evaluate the antitumorigenic effect of dietary (n-3) polyunsaturated fatty acids (PUFA) in the Apc(Min/+) mouse model and to determine whether these effects are related to inhibition of AA metabolism. Male Apc(Min/+)mice were fed diets supplemented with eicosapentaenoic acid (EPA), AA or a combination of AA + EPA. Mean tumor number in the EPA group was 68% lower (P<0.05) compared with the control group, whereas AA supplementation did not significantly alter tumor load. The reduction in tumor load coincided with significant reductions in intestinal AA content and levels of prostaglandins. However, supplementing AA to the EPA diet (AA + EPA) abolished the antitumorigenic effect of EPA, increased tissue AA content fourfold and prostaglandin production two- to fourfold. These results indicate that AA is involved in tumorigenesis and suggest that EPA's ability to reduce tumor load in Apc(Min/+) mice is related to reductions in tissue AA content or its metabolism. 相似文献
62.
63.
Predicting readmission to hospital with asthma 总被引:2,自引:0,他引:2
D RAYMOND RL HENRY N HIGGINBOTHAM & M COORY 《Journal of paediatrics and child health》1998,34(6):534-538
64.
Bolontrade MF; Stern MC; Binder RL; Zenklusen JC; Gimenez-Conti IB; Conti CJ 《Carcinogenesis》1998,19(12):2107-2113
In this study we have analyzed the vascular response induced in the two-
stage carcinogenesis model in SENCAR mice. The role of angiogenesis has not
been explored in this model, which is the paradigm of multistage
carcinogenesis and a model for neoplastic lesions derived from exophytic
premalignant lesions (e.g. colon carcinoma, bladder papilloma). We
investigated if angiogenesis is involved in the formation of papillomas and
in the progression from papilloma to carcinoma. To this end we analyzed the
vasculature of normal and hyperplastic skin, focal epidermal hyperplasias
that are precursors of papillomas, papillomas at different stages and
squamous cell carcinomas. We also analyzed the vascularization of
papillomas induced in two strains of mice that differ in their
susceptibility to malignant progression. We show here that angiogenesis is
turned on in the earliest stages of papilloma formation. In late stages,
regardless of state of progression, the predominant response is an increase
in the size of blood vessels. Thus, in the SENCAR mouse model,
representative of exophytic tumors, the angiogenesis switch is a very early
event, probably mechanistically related to the development of the primarily
exophytic lesions. Therefore, the density of blood vessels cannot be used
as a predictor of malignant progression in this model.
相似文献
65.
K. Whelan J. E. Thomas S. Cooper† R. Hilton‡ S. C. Jones§ T. Newton¶ B. O'Neill & E. E. Gill 《Journal of human nutrition and dietetics》2005,18(6):461-466
BACKGROUND: Interprofessional education (IPE) is a novel teaching and learning initiative where students of more than one health profession learn interactively together. However, despite its potential for improving interprofessional relationships, there is little information regarding the participation of student dietitians in IPE. The aim of this paper was to consider the reaction of student dietitians to an IPE course in order to stimulate debate between dietitians regarding the issues relating to IPE. METHODS: Student dietitians participated in an IPE course consisting of seven sessions on communication and ethics in health care together with students of medicine and nursing. Student dietitians completed an evaluation questionnaire following each session that surveyed their reaction to the session using both a Likert scale and free-text comments. RESULTS: Twenty-six student dietitians completed the IPE course. All sessions were rated positively for interest value (P < or = 0.14), learning experience (P < or = 0.036) and value for clinical practice (P < or = 0.05). The limited number of free-text comments indicated some positive experiences regarding interprofessional learning, teaching content and teaching strategy. CONCLUSIONS: This is one of very few evaluations to describe the reaction of student dietitians to IPE. Student dietitians had largely positive reactions to the IPE course. Further research is required to evaluate whether these positive reactions were a direct consequence of the inclusion of students from other health professions and whether these translate into positive effects on learning, behaviour and results. The opportunities for the dietetic profession posed by students' involvement in IPE are discussed. 相似文献
66.
Objective.To describe the clinical, radiological and MRI features of six atypical cases of histologically proven appendicular Ewing
sarcoma/ primitive neuroectodermal tumour (PNET). Design. Retrospective review of case notes and available imaging was carried out. Patients. Six patients (4 male, 2 female; mean age 27years, range 19–44 years), presenting over a 77-month period, were identified
from the Bone Tumour Register. All had unusual clinical and imaging features for Ewing sarcoma/PNET.
Results and conclusions. Four tumours were centred on the distal femoral metaphysis, one in the proximal tibial metaphysis and one in the distal
tibial metaphysis. Plain radiographs were available in four cases and showed minor cortical changes. MRI demonstrated a relatively
small, eccentrically located intraosseous component with a large, eccentric extraosseous component. Extension into the epiphysis
was seen in three cases and into the adjacent joint in two cases. Intraosseous ”skip” metastases were present in three cases.
The clinical and imaging features were atypical for conventional intraosseous Ewing sarcoma/PNET and the exact site of origin
(intraosseous, periosteal or soft-tissue) was unclear.
Received: 6 December 1999 Revision requested: 7 February 2000 Revision received: 20 July 2000 Accepted: 4 August 2000 相似文献
67.
Bowel transit in two women with protracted constipation was evaluated after oral administration of In-111 DTPA in water. Serial abdominal images were obtained for as long as 96 hours to assess transit through the stomach, small bowel, and colon. In both patients, large bowel transit was delayed. A pattern of colonic inertia was observed in one patient, whereas retention in the distal colon was seen in the other patient. Both patients underwent total colectomy with marked symptomatic relief. Colonic transit studies of these patients are presented, and the literature is reviewed. 相似文献
68.
Craig Gerrand Nick Athanasou Bernadette Brennan Robert Grimer Ian Judson Bruce Morland David Peake Beatrice Seddon Jeremy Whelan On behalf of the British Sarcoma Group 《Clinical sarcoma research》2016,6(1):7
This document is an update of the British Sarcoma Group guidelines published in 2010. The aim is to provide a reference standard for the clinical care of patients in the UK with bone sarcomas. Recent recommendations by the European Society of Medical Oncology, The National Comprehensive Cancer Network and The National Institute for Health and Care Excellence have been incorporated, and the literature since 2010 reviewed. The standards represent a consensus amongst British Sarcoma Group members in 2015. It is acknowledged that these guidelines will need further updates as care evolves. The key recommendations are that bone pain or a palpable mass should always lead to further investigation and that patients with clinico-radiological findings suggestive of a primary bone tumour at any site in the skeleton should be referred to a specialist centre and managed by a fully accredited bone sarcoma multidisciplinary team. Treatment recommendations are provided for the major tumour types and for localised, metastatic and recurrent disease. Follow up schedules are suggested. 相似文献
69.
Using patient‐reported outcome measures to improve service effectiveness for supervisors: a mixed‐methods evaluation of supervisors' attitudes and self‐efficacy after training to use outcome measures in child mental health
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70.