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71.
72.
Canonical Wnt signals are essential for homeostasis of the intestinal epithelium 总被引:25,自引:0,他引:25 下载免费PDF全文
To assess the critical role of Wnt signals in intestinal crypts, we generated transgenic mice ectopically expressing Dickkopf1 (Dkk1), a secreted Wnt inhibitor. We find that epithelial proliferation is greatly reduced coincidentally with the loss of crypts. Although enterocyte differentiation appears unaffected, secretory cell lineages are largely absent. Disrupted intestinal homeostasis is reflected by an absence of nuclear beta-catenin, inhibition of c-myc expression, and subsequent up-regulation of p21CIP1/WAF1. Thus, our data are the first to establish a direct requirement for Wnt ligands in driving proliferation in the intestinal epithelium, and also define an unexpected role for Wnts in controlling secretory cell differentiation. 相似文献
73.
Economic evaluation of pharmaceuticals: a European perspective 总被引:1,自引:0,他引:1
Drummond M Rutten F Brenna A Pinto CG Horisberger B Jönsson B Le Pen C Rovira J von der Schulenburg MG Sintonen H 《PharmacoEconomics》1993,4(3):173-186
In recent years there has been a large increase in the number of economic evaluations of pharmaceuticals. Many of these studies have been commissioned by individual pharmaceutical companies, in support of new or existing products. In 2 countries, Australia and Canada (in the province of Ontario), draft guidelines issued by the government have outlined the requirements for economic evaluations to be submitted in support of requests for reimbursement (government subsidy) of particular products. One consequence of the guidelines is that they clarify what is required, and in specifying the procedure for submission of dossiers, identify a clear audience for the economic evaluation. In contrast, the situation in Europe is diverse. A wide range of healthcare systems exist, including national health services and more liberal systems, involving a wide range of insurers and providers. European countries also differ widely in their approach to the pricing and reimbursement of pharmaceuticals. Because of this diversity, the nature, conduct and impact of economic evaluation in Europe is not clear. It is therefore difficult for pharmaceutical companies to develop appropriate strategies for economic evaluation and for analysts to decide on appropriate study methodology. This article reviews the nature of any official guidance or requirements for economic evaluation, the potential for use of economic evaluation, the range of studies carried out and the identifiable impacts. There is currently no official guidance in any country, although some countries are considering issuing guidelines. In some countries there is official encouragement to pharmaceutical companies to undertake studies, and where economic data have been presented they have been considered by the relevant committees. The potential uses of economic evaluation vary widely from country to country. These can be classified in terms of a potential role in undertaking national price negotiations, deciding on reimbursement status or copayment level, deciding on inclusion in local formularies or in treatment guidelines, or in improving prescribing decisions. Approximately 80 economic evaluations of pharmaceutical products have been conducted to date in Europe, covering a wide range of clinical areas. There are relatively few examples of identifiable effects of such studies. In part this is because it is often difficult to assess the part played by various items of data. Nevertheless, the overriding conclusion is that economic evaluation of medicines is likely to be more relevant in Europe in the future. The problem for the pharmaceutical industry is in determining when and how. 相似文献
74.
Competition in the health care market has intensified in recent years. Health care providers are increasingly adopting innovative marketing techniques to secure their positions in the marketplace. This paper examines an innovative marketing technique, situational segmentation, and assesses its applicability to the health care market. Situational segmentation has proven useful in many consumer goods markets but has received little attention in the context of health care marketing. A two-stage research process is used to develop a taxonomy of situational factors pertinent to health care choice. In stage one, focus group interviews are used to gather information which is instrumental to questionnaire development. In stage two, the responses of 151 subjects to a 51 item questionnaire are factor analyzed. The results demonstrate that situational segmentation is a viable strategy in the health care market. 相似文献
75.
Pinto LF 《Jornal de pediatria》1995,71(5):248-254
The author describes television as a factor of influence in the sexual (mis)education in adolescence. He considers the role of eroticism in television as a dysfunctional factor in the sexual education of youth. In accordance with its pervasion, accessibility and attractive and seductive contents TV may be considered an alternative source and an efficient instrument of sexual (mis)education, because adolescents find in it a lot of information that satisfies their curiosity about the sexual world of adults. This occurs through a process of more and more explicit eroticism that abuses the freedom of sexual expression and exhibition and transmits all kinds of sexual information: faithful, correct, tendentious, preconceptual, ambiguous and distorted. 相似文献
76.
Lutz S Greene J Fitzgerald J Pinto C Jaklevic MC Japsen B Kertesz L Moore JD Pallarito K Scott L 《Modern healthcare》1995,25(38):31-2, 36, 38-42 passim
Modern Healthcare's Up & Comers are working to improve the quality of medical care, expand access to healthcare and formulate a cost-efficient delivery system best suited to the needs of the 21st century. These professionals, 40 or younger, are nominated by our staff and readers as examples of the best healthcare has to offer. 相似文献
77.
The paper addresses some limitations of the QALY approach and outlines a valuation procedure that may overcome these limitations. In particular, we focus on the following issues: the distinction between assessing individual utility and assessing societal value of health care; the need to incorporate concerns for severity of illness as an independent factor in a numerical model of societal valuations of health outcomes; similarly, the need to incorporate reluctance to discriminate against patients that happen to have lesser potentials for health than others; and finally, the need to combine measurements of health-related quality of life obtained from actual patients (or former patients) with measurements of distributive preferences in the general population when estimating societal value. We show how equity weights may serve to incorporate concerns for severity and potentials for health in QALY calculations. We also suggest that for chronically ill or disabled people a life year gained should count as one and no less than one as long as the year is considered preferable to being dead by the person concerned. We call our approach 'cost-value analysis'. 相似文献
78.
The purpose of this investigation was to analyse nurse's role in the organization of the health work at the Informatics Department of the Health Bureau of the city of Ribeir?o Preto, regarding the process of municipalization. We verified that nurses were involved in the organization of this area since its implementation. Nurses also performed organization and control activities related to the production, storage and analysis of the necessary data about the different stages of the health care, as well as training and supervising activities of the individuals who work with the information system. 相似文献
79.
de Almeida CE Pereira AJ Marechal MH Pereira G Cruz JC Ferraz JC Giordani AJ Khalil CM Martins RH Menegussi G Moreira D Rocha JR Pinto MA 《Physics in medicine and biology》1999,44(3):N31-N38
The lack of well established dosimetry protocols for HDR sources is a point of great concern regarding the uniformity of procedures within a particular country and worldwide. The main objective of this paper is to report the results from ten institutions of an intercomparison of calibration procedures for 192Ir HDR sources currently in use in Brazil. The treatment irradiator of one institution was calibrated by a reference system and used by all participants with their own measuring electrometers and ionization chambers under the same experimental conditions. Two methods were used: the calibration jig and the well-type ionization chamber. Each participant was allowed to use their own method and formalism. The results of this exercise were very positive since this was the first time in Brazil that a group of users gathered to share their experience and openly discuss the physical concepts behind the calibration procedures. The results were all within +/-3.0%, except one case where -4.6% was observed and later identified as a problem with the Nk value for x-rays. Though the magnitude of the deviations found was generally acceptable considering the diversity of formalisms currently in use, a proposal is now being prepared to be adopted as a national protocol. The identification of the institutions was left out for the sake of confidentiality. 相似文献
80.
p53 Accumulation Is a Prognostic Factor in Intestinal-Type Gastric Carcinoma but Not in the Diffuse Type 总被引:2,自引:0,他引:2
Roviello F Marrelli D Vindigni C De Stefano A Spina D Pinto E 《Annals of surgical oncology》1999,6(8):739-745
Background: The prognostic value of p53 nuclear accumulation in gastric cancer is still unclear, as shown by the discordant results still reported in the literature. In this study, we evaluated the correlation between p53 accumulation and long-term survival of patients resected for intestinal and diffuse-type gastric cancer.Methods: Eighty-three patients with carcinoma of the intestinal type and 53 patients with carcinoma of the diffuse type were included in the study. Immunohistochemical staining of the paraffin sections was performed by using monoclonal antibody DO1; cases were considered positive when nuclear immunostaining was observed in 10% or more of the tumor cells. Prognostic significance of different variables was investigated by univariate and multivariate analysis.Results: p53 positivity was found in 51.8% of intestinal-type and 50.9% of diffuse-type cases. No significant correlation between the rate of p53 overexpression and age, sex, tumor location, tumor size, depth of invasion, lymph node involvement, distant metastases, and surgical radicality was found in the two groups of patients. A statistically significant difference in survival rate was observed between p53-negative and p53-positive cases in the intestinal type (P < .05), confirmed by multivariate analysis (P < .005; relative risk = 3.09). On the contrary, no correlation with survival was found in diffuse-type cases according to p53 overexpression.Conclusions: These results suggest that the immunohistochemical detection of p53 accumulation is a useful indicator of poor prognosis in the intestinal but not in the diffuse type of gastric cancer, and are indicative of distinct molecular pathways and pattern of progression in the two histotypes. 相似文献