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排序方式: 共有639条查询结果,搜索用时 12 毫秒
61.
Stenström B Zhao CM Rogers AB Nilsson HO Sturegård E Lundgren S Fox JG Wang TC Wadström TM Chen D 《Carcinogenesis》2007,28(9):2041-2046
The Swedish variant of moist oral smokeless tobacco (snus) is popular in Sweden and Norway, banned from sale within the European Union and is currently being introduced in USA. The aim of the present study was to determine if snus is carcinogenic to the stomach, particularly in Helicobacter pylori (H.P.)-infected hosts at increased risk for gastric cancer development. Snus (Generaltrade mark; Swedish Match, Sweden) was mixed with powdered standard mouse chow at a concentration of 5-9% (wt/wt) and given to wild-type (WT, FVB) and gastrin transgenic (INS-GAS, FVB) mice for 6 months with or without H.P. (strain 67:21, CagA+, VacA+) infection. At necropsy, pathological evaluation of stomachs from uninfected snus-treated WT mice showed mild morphological changes, whereas 50% snus-treated INS-GAS mice developed carcinoma in situ (CIS), compared with 25% not exposed to snus. When snus was given to H.P.-infected mice, 9 of 17 WT mice developed CIS with intramucosal invasion, and the remaining 8 of 17 WT mice developed high-grade dysplasia (score >1.5) that was associated with increased gastritis, epithelial defects, oxyntic atrophy, hyperplasia and intestinal metaplasia. Twelve of 12 H.P.-infected INS-GAS mice developed CIS with intramucosal invasion and submucosal herniation. We suggest that snus is a potential gastric carcinogen in mice. The development of CIS was associated with increased rates of the epithelial cell proliferation and apoptosis, common features of gastric carcinogenesis. 相似文献
62.
OBJECTIVE: To compare symptomatic outcome after antibacterial treatment in patients with acute lower urinary tract infection and the acute urethral syndrome. DESIGN: A multipractice study; patients registering symptoms prospectively for 3 days by means of a diary. SETTING: General practices in western Norway. SUBJECTS: 153 adult women with acute lower urinary tract symptoms. MAIN OUTCOME MEASURE: Patient's prospective registration of symptom distribution and duration after starting antibacterial treatment. RESULTS: Fifty-one patients with acute lower urinary tract infection and 58 patients with the acute urethral syndrome were included. There were no differences in age, history of urinary tract infection, actual symptoms, or symptom duration between the groups. Symptom duration was nearly identical in the two groups among those who became asymptomatic during the 3 days of registration, ranging from 1.2 days for urgency to 1.6 days for dysuria. Almost half of the patients in each group still had some symptom left after 3 days. CONCLUSIONS: Symptomatic outcome was equal after antibacterial treatment whether the patient was classified as having acute cystitis or the acute urethral syndrome. Consequently, the general practitioner may rely on symptoms alone when starting antibacterial treatment in adult women with suspected cystitis. 相似文献
63.
Daniel Weiss Erik R. Sund Jeremy Freese Steinar Krokstad 《Sociology of health & illness》2020,42(7):1548-1565
This study investigates patterns of adoption and diffusion of innovative health technologies by socioeconomic status (SES) in order to assess the extent to which these technologies may be a fundamental cause of health-related inequalities. Quantitative analyses examined SES-based inequalities in the adoption and diffusion of diabetes technologies. Diabetes data from three panels of the Nord-Trøndelag Health Study (HUNT), Norway, were combined with income and education data. Cross-sectional and longitudinal regression analyses were used to examine relevant inequalities. Cross-sectional analyses suggest often present SES-based gradients in the adoption of diabetes technologies, favouring high-SES groups. Statistically significant differences (p ≤ 0.05) were most often present when technologies were new. In a cohort followed from 1984 to 1997, high SES individuals were more likely to adopt insulin injection technologies but, due to modest sample sizes, these inequalities were not statistically significant after adjusting for age, gender, and duration of illness. Moreover, compared to low SES individuals, high SES individuals are more active users of diabetes technologies. Results suggest that SES-based variations in access and use of innovative health technologies could act as a mechanism through which inequalities are reproduced. This study provides a discussion of mechanisms and a methodological foundation for further investigation. 相似文献
64.
Ovrebø KK Svanes K Aase S Grong K Kvinnsland S Sørbye H 《Digestive diseases and sciences》2002,47(10):2354-2369
The mucosal changes by which duodenogastric reflux may predispose to gastric cancer have not been fully clarified. In this study in rats, duodenal fluid was directed into the stomach through a gastroenterostomy (jejunal reflux, N = 29) or through the pylorus (pyloric reflux, N = 30) and compared with 30 controls. Twenty-four weeks later the stomach was exposed to N-[3H]methyl-N-nitro-N-nitrosoguanidine ([3H]MNNG). The corpus mucosa was examined for proliferating cells (bromodeoxyuridine labeled) and cells at risk of methyl-N-nitro-N-nitrosoguanidine-induced carcinogenesis (cells labeled with bromodeoxyuridine and [3H]MNNG). The number of double-labeled cells increased from 0.8 ± 0.1/mm mucosa in the control group to 5.2 ± 0.9 in the jejunal reflux group (P < 0.05) and 2.7 ± 0.5 in the pyloric reflux group (P < 0.05). An erosion or ulcer appeared at the gastroenterostomy in 52% of animals with jejunal reflux and 17% of those with pyloric reflux (P < 0.006). Within erosions the mean number of double-labeled cells was 9.6 ± 2.2 in the jejunal reflux group and 7.7 ± 4.8 in the pyloric reflux group, and significantly higher than in the nonlesion area of the mucosa (0.6 ± 0.2 and 0.8 ± 0.3). In erosions the distance between the gastric lumen and the proliferating cells was significantly shorter and the cell proliferation significantly higher than in the nonlesion area of the mucosa. We conclude that duodenogastric reflux increases the penetration of [3H]MNNG into the corpus mucosa of rats and also induces mucosa lesions, which further increase the penetration of [3H]MNNG into the corpus mucosa. 相似文献
65.
66.
Asthildur Erlingsdottir Emil L. Sigurdsson Jon Steinar Jonsson Hildur Kristjansdottir Johann A. Sigurdsson 《Scandinavian journal of primary health care》2014,32(1):11-16
Objective. To study the prevalence and possible predictors for smoking during pregnancy in Iceland. Design. A cross-sectional study. Setting. Twenty-six primary health care centres in Iceland 2009–2010. Subjects. Women attending antenatal care in the 11th–16th week of pregnancy were invited to participate by convenient consecutive manner, stratified according to residency. A total of 1111 women provided data in this first phase of the cohort study. Main outcome measures. Smoking habits before and during early pregnancy were assessed with a postal questionnaire, which also included questions about socio-demographic background, physical and emotional well-being, and use of medications. Results. The prevalence of smoking prior to pregnancy was 20% (223/1111). During early pregnancy, it was 5% (53/1111). In comparison with women who stopped smoking during early pregnancy, those who continued to smoke had on average a significantly lower level of education, had smoked more cigarettes per day before pregnancy, and were more likely to use nicotine replacement therapy in addition to smoking during pregnancy. A higher number of cigarettes consumed per day before pregnancy and a lower level of education were the strongest predictors for continued smoking during pregnancy. Conclusion. The majority of Icelandic women who smoke stop when they become pregnant, and the prevalence of smoking during pregnancy in Iceland is still about 5%. Our results indicate stronger nicotine dependence in women who do not stop smoking during pregnancy. Awareness of this can help general practitioners (GPs) and others providing antenatal care to approach these women with more insight and empathy, which might theoretically help them to quit.Key Words: Antenatal care, childbirth and health, general practice, Iceland, pregnancy, primary health care, smoking habitsSmoking during pregnancy is a major preventable risk factor for foetal and neonatal morbidity and mortality.
- This study shows that the prevalence of smoking during early pregnancy in Iceland is 5%.
- A history of heavy smoking before pregnancy and low level of education characterize the women who do not stop smoking early in pregnancy.
- Our results can help GPs and midwives to identify women at risk of continued smoking during pregnancy and possibly assist them to quit.
67.
Kjell K. Ovrebo Halfdan Sorbye Steinar Kvinnsland Ketil Grong Knut Svanes 《Digestive diseases and sciences》1998,43(9):2012-2020
Clinical conditions with low gastric acidsecretion have been associated with increased risk ofgastric cancer. There has also been concern aboutgastric acid inhibition and N-nitroso compound formation in the stomach. This study investigates theeffect of gastric acid secretion on the penetration ofN-3H-methyl-N-nitro-N-nitrosoguanidine, anN-nitroso compound and gastric carcinogen, into thegastric mucosa of rats. Gastric acid secretion wasstimulated by pentagastrin (40 g/kg/hr) andinhibited by omeprazole (40 mumol/kg) before mucosalexposure toN-3H-methyl-N-nitro-N-nitrosoguanidine.Penetration of the carcinogen was evaluated by lightmicroscopic identification of cells in the S-phaselabeled withN-3Hmethyl-N-nitro-N-nitrosoguanidine. Thispopulation of double-labeled cells is considered at risk fromN3-methyl-N-nitro-N-nitrosoguanidine-inducedcarcinogenesis. The percentage of double-labeled cellswas significantly higher in antrum than in corpus mucosa(P < 0.0001). Stimulation or inhibition of gastric acid secretion did notaffect the penetration of N-3H-methyl-N-nitro-N-nitrosoguanidine in antrum or corpusmucosa. We conclude that modulation of gastric acidsecretion does not affect the penetration of the carcinogeninto the gastric mucosa nor does it explain thedifferent penetration of the carcinogen into corpus andantrum mucosa. 相似文献
68.
Olafsdottir LB Gudjonsson H Jonsdottir HH Jonsson JS Bjornsson E Thjodleifsson B 《World journal of gastroenterology : WJG》2012,18(28):3715-3720
AIM: To study if and how physicians use the irritable bowel syndrome (IBS) diagnostic criteria and to assess treatment strategies in IBS patients. METHODS: A questionnaire was sent to 191 physicians regarding IBS criteria, diagnostic methods and treatment. Furthermore, 94 patients who were diagnosed with IBS underwent telephone interview. RESULTS: A total of 80/191 (41.9%) physicians responded to the survey. Overall, 13 patients were diag-nosed monthly with IBS by specialists in gastroenterology (SGs) and 2.5 patients by general practitioners (GPs). All the SGs knew of the criteria to diagnose IBS, as did 46/70 (65.7%) GPs. Seventy-nine percent used the patient’s history, 38% used a physical examination, and 38% exclusion of other diseases to diagnose IBS. Only 18/80 (22.5%) physicians used specific IBS criteria. Of the patients interviewed, 59/94 (62.8%) knew they had experienced IBS. Two out of five patients knew IBS and had seen a physician because of IBS symptoms. Half of those received a diagnosis of IBS. A total of 13% were satisfied with treatment. IBS affected daily activities in 43% of cases. CONCLUSION: Half of the patients with IBS who consulted a physician received a diagnosis. Awareness and knowledge of diagnostic criteria for IBS differ between SGs and GPs. 相似文献
69.
Stocks T Van Hemelrijck M Manjer J Bjørge T Ulmer H Hallmans G Lindkvist B Selmer R Nagel G Tretli S Concin H Engeland A Jonsson H Stattin P 《Hypertension》2012,59(4):802-810
Observational studies have shown inconsistent results for the association between blood pressure and cancer risk. We investigated the association in 7 cohorts from Norway, Austria, and Sweden. In total, 577799 adults with a mean age of 44 years were followed for, on average, 12 years. Incident cancers were 22184 in men and 14744 in women, and cancer deaths were 8724 and 4525, respectively. Cox regression was used to calculate hazard ratios of cancer per 10-mmHg increments of midblood pressure, which corresponded with 0.7 SDs and, for example, an increment of systolic/diastolic blood pressure of 130/80 to 142/88 mmHg. All of the models used age as the time scale and were adjusted for possible confounders, including body mass index and smoking status. In men, midblood pressure was positively related to total incident cancer (hazard ratio per 10 mmHg increment: 1.07 [95% CI: 1.04-1.09]) and to cancer of the oropharynx, colon, rectum, lung, bladder, kidney, malignant melanoma, and nonmelanoma skin cancer. In women, midblood pressure was not related to total incident cancer but was positively related to cancer of the liver, pancreas, cervix, uterine corpus, and malignant melanoma. A positive association was also found for cancer mortality, with HRs per 10-mmHg increment of 1.12 (95% CI: 1.08-1.15) for men and 1.06 (95% CI: 1.02-1.11) for women. These results suggest a small increased cancer risk overall in men with elevated blood pressure level and a higher risk for cancer death in men and women. 相似文献
70.