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991.
BACKGROUND: Colorectal cancer is the second most common cause of cancer-related death in Scotland. For patients, the journey from diagnosis through treatment is complex and there are inequalities in survival rates. OBJECTIVES: The aim of the present study was to explore how patients with colorectal cancer perceive their care. METHODS: This was a qualitative study involving 95 patients and relatives of patients with colorectal cancer in the North, Northeast and Northern Isles, Scotland. Focus groups (32 participants) were conducted in hospital, and interviews (63 participants) in patients' own homes in order to explore their experiences of health services for cancer-what was good, what was bad and what was needed. Analysis was inductive, with exploration of similar and divergent perspectives within themes. RESULTS: Patients wanted rapid diagnosis, specialist treatment and good communication, but their experiences of and perspectives on these areas were often divergent. Delays in diagnosis could stem from late presentation by patients, but also from early presentation when the cancer could go undetected. GP continuity was desirable, but sometimes implicated in delays. Patients preferred their GPs to be advocates, not gatekeepers. The context, however, was one where some patients pursued their care tenaciously while others did not. For some, speed of progress through the system was everything, but others found this could be impersonal. Outlying patients had to balance transport difficulties with the benefits of distant specialist treatment. Some patients wanted full information to be provided directly, but others could not cope with this. CONCLUSIONS: From patients' perspectives, ideal cancer care cannot be achieved in a uniform way. For some of the key goals of cancer treatment to be met, including rapid access to specialist treatment for all and good communication of bad news and test results, a balance must be struck which tailors care to individuals. 相似文献
992.
In recent years, ethnographic research has challenged the notion within demography that fertility-related behaviour is the outcome of individualistic calculations of the costs and benefits of having children. Anthropology has further criticised the abstraction in demographic analysis of sexual behaviour and fertility decision-making from the socio-cultural and political context in which the individual or couple is located. Within demography itself, institutional and political-economic analyses have argued strongly that sexual and reproductive behaviour must be understood within locally specific social, cultural, economic and political contexts. Positivist and empiricist research methods, such as the sample survey and focus groups, which continue to dominate demographic inquiry and applied research into sexual and reproductive behaviour, have been shown to be limited in their ability to inform about the process of behaviour change and contexts within which different behaviours occur. The article introduces a new methodology for researching sexual and reproductive behaviour, called the peer ethnographic approach, which the authors have developed in an attempt to address some of the limitations of the methods which currently dominate research into sexual and reproductive behaviour. The peer ethnographic methodology is discussed in detail and the results of recent field-testing are reported, which show that, although the approach has limitations, it also has the potential to make a significant contribution to our understanding of sexual and reproductive behaviour. 相似文献
993.
994.
Reiss R Mackay N Habig C Griffin J 《Environmental toxicology and chemistry / SETAC》2002,21(11):2483-2492
A modeling study was conducted to examine the distribution of concentrations of the antimicrobial triclosan (2,4,4'-trichloro-2'-hydroxydiphenyl ether) in rivers following discharge from wastewater treatment plants (WWTPs). Most uses of triclosan are disposed of down residential drains and ultimately reach WWTPs. A modeling analysis was conducted to simulate the discharge of triclosan in WWTP effluents to rivers and calculate the expected concentrations based on characteristics of the reach where the discharge occurred, the estimated concentration of triclosan in the WWTP effluent, and the physicochemical properties of triclosan. A probabilistic exposure assessment was conducted based on data on the characteristics of U.S. reaches receiving wastewater discharges and the physicochemical characteristics of triclosan. A risk assessment was conducted by comparing the estimated concentrations with toxicity endpoint concentrations for species representative of key ecological groups. For fish and invertebrates, neither acute nor chronic risks are of concern, and no concerns exist for vascular aquatic plants. However, certain types of algae are the most sensitive species to triclosan by more than an order of magnitude than other algal or aquatic plant species. For these algae, the potential exists for some risk from triclosan exposure near the WWTP discharge location during low-flow-rate periods for some WWTPs with small dilutions. The risks downstream are lower because of dissipation of triclosan. 相似文献
995.
González MJ Miranda-Massari JR Mora EM Jiménez IZ Matos MI Riordan HD Casciari JJ Riordan NH Rodríguez M Guzmán A 《Puerto Rico health sciences journal》2002,21(1):39-41
The effect of vitamin C in cancer has been a subject of great controversy; mainly because of the inconsistent results obtained by oral intakes of ascorbate when used as an anticancer agent. We believe the intravenous application of ascorbate will provide more consistent results in cancer patients since Vitamin C blood levels attained are substantially higher in a range proven cytotoxic to malignant cells. In this article we will present and discuss our proposed mechanism on the chemotherapeutic activity exhibited by ascorbate. 相似文献
996.
Can cardiovascular risk factors explain the association between education and cardiovascular disease in young women? 总被引:1,自引:0,他引:1
We sought to explain the observed variation in the relationship between education and cardiovascular disease (CVD) among young women in countries at different stages of economic development. Data comprised 2,478 cases of acute myocardial infarction (AMI) or stroke and 6,819 age-matched controls from Africa, Asia, Eastern Europe, and Latin America. The risks of AMI associated with lower education observed in Eastern Europe and higher education in non-European countries were reduced by 92% in Eastern Europe and totally abolished in non-European countries by adjustment for standard cardiovascular risk factors. The inverse associations between education and stroke risk in the three non-African regions were attenuated by 22, 47, and 60% after adjustment. In Africa, the slight inconsistent trend towards lower stroke risk in less well educated women was unaffected by adjustment. These data suggest that standard risk factors explain a substantial proportion if not all of the difference in AMI risk associated with education but a lesser proportion of educationally linked stroke risk. 相似文献
997.
Hasen KV Few JW Fine NA 《Oncology (Williston Park, N.Y.)》2002,16(12):1685-98; discussion 1698, 1702-5, 1708
Plastic surgery represents a small but critical component of the comprehensive care of cancer patients. Its primary role in the treatment of cancer patients is to extend the ability of other surgeons and specialists to more radically treat cancer, offering patients the best opportunity for cure. Although the most convincing data for improved psychosocial well-being through plastic surgery is in the setting of breast cancer reconstruction after mastectomy, it is reasonable to assume that all patients who undergo major reconstruction to minimize deformity due to cancer therapy feel some improvement in quality of life. This article will provide an overview of the role of plastic surgery in cancer treatment. 相似文献
998.
Anti-tumor activity of GW572016: a dual tyrosine kinase inhibitor blocks EGF activation of EGFR/erbB2 and downstream Erk1/2 and AKT pathways 总被引:10,自引:0,他引:10
Xia W Mullin RJ Keith BR Liu LH Ma H Rusnak DW Owens G Alligood KJ Spector NL 《Oncogene》2002,21(41):6255-6263
Dual EGFR/erbB2 inhibition is an attractive therapeutic strategy for epithelial tumors, as ligand-induced erbB2/EGFR heterodimerization triggers potent proliferative and survival signals. Here we show that a small molecule, GW572016, potently inhibits both EGFR and erbB2 tyrosine kinases leading to growth arrest and/or apoptosis in EGFR and erbB2-dependent tumor cell lines. GW572016 markedly reduced tyrosine phosphorylation of EGFR and erbB2, and inhibited activation of Erk1/2 and AKT, downstream effectors of proliferation and cell survival, respectively. Complete inhibition of activated AKT in erbB2 overexpressing cells correlated with a 23-fold increase in apoptosis compared with vehicle controls. EGF, often elevated in cancer patients, did not reverse the inhibitory effects of GW572016. These observations were reproduced in vivo, where GW572016 treatment inhibited activation of EGFR, erbB2, Erk1/2 and AKT in human tumor xenografts. Erk1/2 and AKT represent potential biomarkers to assess the clinical activity of GW572016. Inhibition of activated AKT in EGFR or erbB2-dependent tumors by GW572016 may lead to tumor regressions when used as a monotherapy, or may enhance the anti-tumor activity of chemotherapeutics, since constitutive activation of AKT has been linked to chemo-resistance. 相似文献
999.
1000.
Many therapeutically active anticancer treatments exert their effect by the induction of apoptosis and necrosis. Serial biopsies in breast cancer patients have suggested that response to therapy correlates with early posttreatment increases in tumor apoptotic index. Radiolabeled technetium Tc 99m-recombinant human (rh) annexin V provides a noninvasive technique for imaging treatment-induced cell death. Annexin V is a naturally occurring human protein that binds avidly to membrane-associated phosphatidylserine (PS). PS is normally found only on the inner leaflet of the cell membrane double layer, but it is actively transported to the outer layer as an early event in apoptosis and becomes available for annexin binding. Annexin also gains access to PS as a result of the membrane fragmentation associated with necrosis. In vitro studies of apoptosis using fluorescein annexin have shown good correlation with assessments of apoptosis documented by nuclear DNA degradation and caspase activation. In vivo localization of intravenously administered Tc 99m-annexin V has been demonstrated in numerous preclinical models of apoptosis, including anti-Fas-mediated hepatic apoptosis, rejection of allogeneic heterotopic cardiac allografts, cyclophosphamide treatment of murine lymphoma, cyclophosphamide-induced apoptosis in bone marrow, and leukocyte apoptosis associated with abscess formation. Scintigraphic studies in humans using Tc 99m-rh annexin V have demonstrated the feasibility of imaging cell death in acute myocardial infarction, in tumors with a high apoptotic index, and in response to anti-tumor chemotherapy of non-small cell lung cancer, small-cell lung cancer, breast cancer, lymphoma, and sarcoma. Increased localization of Tc 99m-rh annexin V within 1 to 3 days of chemotherapy has been noted in some, but not all, subjects with these tumors. To date, most subjects showing increased Tc 99m-rh annexin V uptake after the first course of chemotherapy have shown objective clinical responses. A single site study in 15 subjects with 1-year follow-up has suggested that increased posttreatment Tc 99m-rh annexin uptake is associated with improved time to progression of disease and survival time. In vivo imaging of cell death may have the potential to improve the treatment of cancer patients by allowing rapid, objective, patient-by-patient assessment of the efficacy of tumor cell killing. 相似文献