ISSN:0959-8278    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

Oesophageal cancer is a substantial cause of mortality in the Western world and recent data indicate that the incidence is increasing. Despite better understanding of the pathogenesis and in the surgical management of the disease, little improvement in the survival rates has been achieved anywhere in the world, especially because screening for detection of premalignant lesions cannot, at present, be adequately applied to populations at risk. The present review summarizes current knowledge of the use of conventional screening methods as well as possible applications of new techniques to targeted populations to permit earlier diagnosis of premalignant lesions of the oesophagus.

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:

The authors have hypothesized that iodine-deficiency (I-def) or in some cases iodine-excess (I-excess) is associated with the development of gastric cancer. They report a short review of their own work and general literature on this subject in three fields: (1) epidemiology, where geographical and temporal correlations between territories with I-def (or I-excess) endemic goitre and high GC-death rate are reported; (2) immunology, where the possible correlations between I-def, immune-deficiency and GC are reported; and (3) thyroid gland and stomach correlations, both being embryologically derived from primitive gut and able to concentrate iodine. This ability is impaired by nitrates, thiocyanate, salt and by I-excess, which in fact can cause goitre. In our study I-def goitrous people have shown more atrophic gastritis than normal subjects. These data enable us to hypothesize that I-def or I-excess might constitute a new risk factor for gastric cancer, both by regulating gastric trophism and by antagonizing the action of those I-inhibitors (such as nitrates, thiocyanate and salt) previously studied as risk factors for gastric cancer.

ISSN:0959-8278    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

The concentration of N-nitrosamines (NNA) in gastric juice was determined as an indicator of intragastric N-nitrosation in 85 subjects from a high-risk area for gastric cancer (GC) to examine the relationship between N-nitroso compounds (NOC), pH and intragastric lesions under strictly controlled conditions. Mean gastric pH in subjects with GC or dysplasia (Group GD, 5.0 ± 2.7) was higher than that from subjects with intestinal metaplasia (Group IM, 3.8 ± 2.1,p= 0.068) and significantly higher than in those with normal mucosa or superficial gastritis (Group NS, 2.6 ± 1.9,p< 0.001). No significant difference (p> 0.1) was found in total NNA concentrations between the three groups (GD 1.81 ± 1.05 μg/1, IM 1.46 ± 0.79 μg/1, NS 1.56 ± 1.38 μg/1). However, two obvious peaks of nitrosation were observed at pH ranges of < 2.0 and 5.5–7.5. These observations were confirmed by using the N-nitrosoproline test in the same subjects under the same conditions (r= 0.772,p< 0.05). These results indicate that intragastric nitrosation can occur in both acidic and nearly neutral conditions. The first peak is related to acid-catalysed nitrosation (ACN) and the second is related to biologically catalysed nitrosation (BCN). According to these and other published results the hypothesis that there are two basic mechanisms, ACN and BCN, for intragastric N-nitrosation in humans is explored. Gastric carcinogenesis in high-risk areas is more likely to be related to intragastric NOC formed by ACN, compared to low-risk areas where it is more likely to be related to intragastric NOC formed by BCN. Fruit juices and orange peel significantly inhibited intragastric nitrosation by both ACN and BCN.

ISSN:0959-8278    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

Previous work has established that women who attend for mammography differ from non-attenders in a number of socio-demographic and attitudinal characteristics. The present study was conducted to determine whether women who attended for mammography differed from non-attenders in a number of key areas: (1) in how they obtained information about screening; (2) in their understanding of the disease and basic screening precepts: and (3) in the extent to which they perceived their general practitioners (GPs) and other members of the primary case team, such as practice nurses, had actively promoted the programme. Three hundred attenders and 300 non-attenders were interviewed in their own homes using a structured questionnaire. Only 5% of women interviewed had ever asked their GP for any advice about breast screening, and only 18% recalled their family doctor ever discussing or raising the subject with them. Although attenders and non-attenders differed significantly in their understanding of the scope and purpose of screening, both groups obtained information more often from friends and relatives and broadcast media than fromofficialsources. Attenders were more likely to cite material in the GP's surgery as an important source of information (x2= 5.1,p= 0.02). Attenders were marginally more likely than non-attenders to have previously attended a well-woman clinic in primary care (x2= 3.1,p= 0.08) and were more likely to say that such clinics were being offered by their family doctor (x2= 9.8,p= 0.008). Attenders were no more likely to have asked for advice or to have been given counsel from their GP regarding mammography. These results suggest that women may retain information to which they are exposed in routine surgeries but that women currently attending well-woman clinics are probably a selected group unrepresentative of all those who are to be invited for screening. The majority of Northern Irish women do not actively seek advice about mammography from their family doctor.

ISSN:0959-8278    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

Alkylating antineoplastic drugs (ADs) are carcinogenic to humans and most ADs cause reproductive failures in animal experiments. Studies of occupationally exposed health personnel have shown increased risks for miscarriages (two studies), malformations (two studies) and leukaemia (two studies). During the past decade, work practice guidelines have been issued by authorities in several countries but universal agreement on a set of guidelines which would secure both the work environment and the treatment of patients is yet to come. We reviewed the existing guidelines in the European Community (EC) countries on health personnel's handling of ADs. Five countries had guidelines on the safe handling of ADs. The main principles were to use exhaust cabinets and personal protective equipment. Two sets of guidelines included recommendations for pregnant women. In general, the EC countries' guidelines were less extensive than those issued by the US Occupational Safety and Health Administration. It is argued that the existence of more uniform guidelines in all the member states would be valuable. Specifically, measures should be devised to prevent adverse effects on reproduction.

ISSN:0959-8278    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

Barrett's oesophagus is a pre-malignant condition with an increased risk of adenocarcinoma. The prevalence of adenocarcinoma in Barrett's oesophagus is about 10% but its true incidence in the general population is unknown. The development of adenocarcinoma in Barrett's oesophagus is a multi-step process. Gastro-oeso-phageal reflux symptoms are absent in many Barrett's patients and both Barrett's oesophagus and adenocarcinoma are usually but not always diagnosed simultaneously. When a carcinoma is identified, the treatment of choice is resection. Three-stage oesophagectomy is considered the most appropriate procedure. The prognosis of Barrett's carcinoma is dismal and the survival rate is related to stage of the tumour. However, encouraging results have been reported in the past 5 years. Endoscopic surveillance for Barrett's oesophagus is still a controversial topic but for some high-risk subgroups of patients regular surveillance is advocated. At the present time, dysplasia is the best available indicator of malignancy in Barrett's oesophagus.

ISSN:0959-8278    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

The prevalence of precancerous lesions of the oesophagus and their association with alcohol drinking, tobacco smoking and some dietary factors were examined in an endoscopic survey carried out in Lower Normandy, France, a high-risk area for oesophageal cancer. The study included 134 male volunteers of 35–64 years of age. In 124 of the volunteers oesophageal biopsies were evaluable. At histology, the prevalence of chronic oesphagitis, epithelial atrophy and dysplasia was 63%, 1.6% and 4.8%, respectively. The prevalence of these precancerous lesions was significantly associated with cigarette smoking and frequent consumption of butter.

ISSN:0959-8278    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

Increase of ornithine decarboxylase (ODC) activity is known to be associated with cell proliferation and, very likely, with tumour promotion. This prompted us to study the activity of ODC in gastric mucosa of patients with chronic atrophic gastritis that has been considered as a precursor of stomach cancer. Examination of 124 patients with this disease revealed the considerable increase in ODC activity in atrophic mucosa (29.8 ± 2.9vs7.9 ± 1.8 units in normal mucosa,p= 0.001). Supplementation of the patient's diet with beta-carotene (20 mg daily during 3 weeks) results in a statistically significant decrease in ODC activity in gastric mucosa. The data obtained confirm the possibility of application of ODC determination to the detection of early premalignant lesions and suggest the antipromoter activity of beta-carotene in gastric carcinogenesis.

ISSN:0959-8278    

出版商:OVID    

年代:1993

数据来源: OVID