ISSN:0959-8278    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

Platelet-derived growth factor (PDGF) is a potent mitogen for a variety of cells. Abnormal PDGF activity has been reported in many chronic diseases including cancer. Existing data suggest that fluctuations or reset homeostasis in normal growth factor production due to specific agents or changes in cellular environment are potential mechanisms of colonic carcinogenesis. Currently identified risk factors for colorectal cancer include diet, non-steroidal anti-inflammatory drug use, alcohol consumption and physical activity. Certain constituents of diet, including retinoids, fish oils and soybeans, inhibit the activity of PDGF and could reduce paracrine stimulation of the colonic epithelium. Aspirin and physical activity, through reduction in platelet aggregation, may inhibit platelet release of PDGF and lead to reset homeostasis. Alcohol affects platelet aggregation and, depending on consumption patterns, could alter platelet release of PDGF. It is important to determine which of these environmental factors may result in transient effects on growth factor activity and which result in long-term adaptive responses. Further studies could examine the impact of these risk factors on (1) growth factor communication between colonic epithelial cells and fibroblastsin vitroand (2) PDGF concentrations and mitogenic activity in blood and tissue obtained in population-based studies of colorectal cancer.

ISSN:0959-8278    

出版商:OVID    

年代:1993

数据来源: OVID

ISSN:0959-8278    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

Diet has been identified as a risk factor for various cancers. The geographic distribution of cancer frequency within the European Economic Community shows how the Mediterranean area has the lowest incidence rates for most tumours associated with diet. The first studies on diet and cancer realized in this area are fairly recent and their results have been especially informative. This article endeavours to review Spanish epidemiological studies on diet and cancer, highlighting the most important findings on colorectal, stomach, bladder and breast cancer and the repeated observations of the protective effect of high vegetable consumption of different tumours.

ISSN:0959-8278    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

In order to evaluate the effectiveness of colorectal cancer screening by the faecal occult blood test (FOBT) in Germany a population-based case-control study was conducted in Saarland, a southwestern state of Germany. As cases, we identified 522 persons (244 males, 278 females) who died of colorectal cancer between 1983 and 1986 between the ages of 55 and 75 years. For 163 male cases complete screening histories were retrieved together with up to five age-matched controls who had not died of colorectal cancer identified from the files of the case's referring general practitioner (GP). For 209 female cases screening histories were retrieved from their GPs and gynaecologists as well as for age-matched controls. Individual screening histories were established with emphasis on identifying whether FOBTs were carried out asymptomatically or symptomatically. In the time period 6–36 months prior to diagnosis 13|X%of the male cases and 14|X% of the male controls had at least one asymptomatic FORT with a corresponding matched odds ratio of 0.92 (95|X%CI: 0.61, 1.75). For the same prediagnostic period 16|X% of the female cases and 29|X% of the female controls had at least one asymptomatic FOBT leading to an odds ratio of 0.43 (95|X% CI: 0.27, 0.68). Thus, for males where participation rates are generally low, no protective effect could be seen but for females where participation rates are higher a clear protective effect is seen. Possibilities for bias need to be taken into consideration when interpreting these results. Organizational measures ensuring a high penetrance of a mass screening programme are seen as a way to elevate efficacy.

ISSN:0959-8278    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

Good compliance with screening programmes is essential and experience from ongoing studies points to the importance of involving general practitioners (GPs). The aim of this study was to evaluate factors influencing the participation of GPs in a screening programme, as well as acceptance of the test by the population. Fifty GPs were randomly chosen among the 117 practices of three districts in Calvados (France) where Haemoccut test-based mass screening for colorectal cancer was underway. Each GP was asked to fill in a personal questionnaire as well as a detailed record for each patient between 45 and 74 years seen in the practice during a 1-week period. The GPs offered the test to 95|X% of the patients. The overall refusal rate was 7.8|X%, and was higher in women than in men (9.9|X%vs5.9|X%; P < 0.05). Manual workers had a lower refusal rate than other occupational groups (2.5|X% vs 8.5|X%; P < 0.05). The GP's motivation was an important factor in patient compliance: the refusal rate was 5.4|X% in the case of highly motivated GPs, against 20.0|X%when the GP was poorly motivated (P < 0.01). GP motivation was higher in urban than in rural areas (P < 0.05) but did not depend on sex, age or the duration or type of practice. According to the GPs, motivating factors were the perceived need for screening, involvement in planning the campaign, and regular feedback. Conversely, a lack of time and the possibility of false-negative results were the most important impediments. This study demonstrates that patient compliance is closely linked to practitioner motivation. Good GP motivation requires specific organization,eginvolvement in planning the screening programmes from the outset, continual feedback on results, and prior training course.

ISSN:0959-8278    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

An attempt was made to undertake a randomized clinical trial of weight reduction in obese postmenopausal breast cancer patients as an adjuvant to primary surgical and radiotherapeutic treatment. The rationale was to improve prognosis which has been shown to be worse in the obese (probably because of its effect on extra-ovarian oestrogen production). Difficulties in recruiting a sufficient number of patients and the introduction of tamoxifen as anti-oestrogenic adjuvant therapy led to the decision to modify the aim of the study by limiting it to a feasibility study in 102 patients. In three hospitals in The Netherlands and in two hospitals in Poznan, Poland these patients were randomized in intervention and control groups according to a 3:2 ratio. Weight reduction in the intervention group was achieved by dietary means,iecaloric restriction was adapted to personal needs and behaviour of the patients. After 1 year a median weight loss of 6 kg was reached in both countries. In The Netherlands further follow-up indicated that this result could be maintained for another 2 years.

ISSN:0959-8278    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

We compared the gastric mucosa lesions of 63 direct relatives of 24 patients with gastric carcinoma with those observed in 151 dyspeptic patients and in seven members of a family with familial gastric carcinoma of diffuse type. We found a higher prevalence ofHelicobacter pyloriinfection (96.8|X%) and gastritis (98.4|X%) in the relatives of patients with sporadic carcinoma than in the dyspeptic patients. One-third of the individuals of the former group displayed chronic atrophic gastritis and intestinal metaplasia. Dysplasia was only observed in the group of cancer patient relatives. The relatives of patients with intestinal carcinoma showed a higher prevalence of chronic atrophic gastritis (40.0|X%), incomplete intestinal metaplasia (22.9|X%) and dysplasia (5.7|X%) than the relatives of patients with diffuse carcinoma (10.0|X%, 0.0|X% and 0.0|X%, respectively). The only striking feature that emerged from the comparison of relatives of patients with sporadic gastric carcinoma with the members of the family with familial gastric carcinoma was the significantly higher prevalence of hyperplastic lesions (100|X%) in the latter group. These results reinforce the existence of two main pathways of carcinogenesis of gastric mucosa, one leading to intestinal carcinoma via chronic atrophic gastritis and intestinal metaplasia and the other leading to diffuse carcinoma via hyperplastic changes.

ISSN:0959-8278    

出版商:OVID    

年代:1993

数据来源: OVID

ISSN:0959-8278    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

In recent years, the countries of central and eastern Europe, the Baltic States, and the newly-independent countries (established in place of the former Soviet Union), have experienced a much heavier burden of cancer as compared to other subregions of Europe. This appears to be the result of a decline in the standard of health care services, environmental neglect and the high prevalence of health-damaging behaviour, smoking in particular. Their anti-cancer potential falls short of their needs. The existing and still widening gap between what are considered best and worst patterns, practices and prospects in cancer control in Europe has posed a challenge to both the World Health Organization (WHO) and the international cancer community. On WHOs initiative, a group of major European cancer organizations is determined to use their considerable potential, both moral and scientific, in supporting national efforts in all possible ways in those countries that need progress. Recently, WHO has initiated an all-European alliance with the intention of narrowing the gap between what are regarded as best and worst patterns, practices and prospects in cancer control in Europe.

ISSN:0959-8278    

出版商:OVID    

年代:1993

数据来源: OVID