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B Moum  A Ekbom  M H Vatn  E Aadland  J Sauar  I Lygren  T Schulz  N Stray    O Fausa 《Gut》1997,40(3):328-332
BACKGROUND: The incidence figures for ulcerative colitis (UC) and Crohn's disease (CD) have been difficult to interpret, and geographical variations may be due to differences in classification criteria and study design. Few studies have based the incidence on prospective systematic follow up to confirm the initial diagnosis. METHODS: Between 1990 and 1993, in a prospective incidence study of inflammatory bowel disease (IBD) in south eastern Norway, 527 cases of UC, 228 cases of CD, 36 cases of indeterminate colitis (IND), and 55 cases of possible IBD were identified, yielding an annual incidence of 13.6, 5.9, 0.9, and 1.4 per 10(5) respectively. The diagnosis and all clinical data were reviewed by two gastroenterologists independently of each other. One to two years after diagnosis, all patients were offered a clinical follow up in which the initial diagnosis was assessed. RESULTS: Between the time of diagnosis and the follow up, 16 patients had died, four of complications related to IBD. Of the remaining 830 patients, 98% (814/830) were available for follow up, 93% (772/830) attended a clinical examination which included a colonoscopy in 77% (637/830), and the remainder had had a telephone interview, or reassessment based on hospital records, or both. Twenty seven patients were reclassified as not having IBD (3%), and 65 patients were characterised as possible IBD (8%). Of the patients initially classified as UC, 88% had their diagnosis confirmed, compared with 91% with an initial diagnosis of CD. In patients with indeterminate colitis, 33% were classified as definite UC and 17% as CD. This reclassification of patients yielded a corrected annual incidence of 12.8 for UC and 6.0 for CD. CONCLUSION: At follow up one to two years after the diagnosis of IBD, the initial incidence was only marginally altered. This is probably due to uniform inclusion criteria and careful diagnostic methods. The study also illustrates the importance of the re-evaluation of the initial diagnosis as close to 10%, both among patients with UC and CD, were reclassified at follow up.  相似文献   
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Highly malignant cell lines and low-malignant cell lines isolated from three different methylcholanthrene-induced murine fibrosarcomas were examined for their ability to attach to plastic dishes and collagen-coated dishes under serumfree conditions and in the presence of serum. Most of the cells from the three highly malignant lines attached and spread under all conditions. By 72h, there was a significant increase in the number of cells indicating that at least some of the cells had undergone division (even in the absence of serum). In contrast, fewer of the cells from the three low-malignant lines attached and spread on the plastic or collagen substrates in the absence of serum or in the presence of 0.1 per cent serum. However, when 15g laminin per dish was added along with the lowmalignant cells, they then attached and spread on the plastic and collagen-coated dishes. Previous studies have indicated that the highly malignant lines express cell surface antigens that cross-react with laminin while the low-malignant cell lines do not. We speculate that the differences between the high- and low-malignant cells in the expression of cell surface laminin-like antigens contribute to the dissimilarities in attachment and spreading capacity. These differences may also contribute to the dissimilarity between these cells in malignant potential.  相似文献   
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To determine whether the use of an electronic, sensor based stethoscope affects the cardiac auscultation skills of undergraduate medical students.  相似文献   
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Genomic typing of in vitro amplified DNA with sequence-specific oligonucleotide (SSO) probes was performed for DRB1, DQA1, DQB1, DPA1 and DPB1 alleles in 54 random Norwegian rheumatoid arthritis (RA) patients and 181 healthy controls. DRB1 alleles encoding the serological specificity DR4 were found in 80% of the patients, compared to 34% of the controls (relative risk = 7.9, p less than 0.0001). All DR4-positive RA patients carried either DRB1*0401 (Dw4), 0404 (Dw14), or 0405 (Dw15), while no patients were found to carry DRB1*0402 (Dw10) or 0403 (Dw13). The frequency of the DRB1*0101 allele encoding DR1 was not increased, even among DR4-negative RA patients, and we were unable to detect any sharing of other class II alleles among DR4-negative patients. No contribution of any DQA1, DQB1, DPA1 or DPB1 alleles to RA susceptibility could be detected. The results suggest that in the Norwegian population RA is primarily associated with a shared sequence at residues 67-74 of the DR beta 1 chain, but only when this sequence is expressed on DR4 molecules.  相似文献   
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Infection by Toxoplasma gondii may lead to complications in the foetus if the mother suffers from primary infection during pregnancy . Previously infected women have produced toxoplasma‐specific IgG antibodies. The most recent study on prevalence of toxoplasma IgG in the Norwegian pregnant population was conducted 20 years ago. The present study is part of a research programme initiated by the Norwegian Institute of Public Health. We aimed to update the knowledge regarding the prevalence of toxoplasma IgG among pregnant women in Norway. In this cross‐sectional study, sera from 1922 pregnant women in Buskerud (992) and Sør‐Trøndelag counties (930) in Norway were collected consecutively. The presence of toxoplasma IgG was identified by values ≥8 IU/mL using an ELISA test. The overall prevalence of toxoplasma IgG seropositivity was 9.3% (95% CI 8.1–10.7); Sør‐Trøndelag 10.4% (95% CI 8.6–12.6) and Buskerud 8.3% (95% CI 6.7–10.2). There was no difference between the counties (p = 0.13), and the result did not differ from prevalences found in 1974 (12.1%) and 1994 (10.7%). We found a higher prevalence among women ≥40 years (OR 2.65, 95% CI 1.30–5.42). The prevalence of toxoplasma IgG among pregnant women in Norway is low and has been stable during the last decades.  相似文献   
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In clinical practice, it is commonly assumed that occlusal splints have therapeutic value in the treatment of temporomandibular disorders (TMD), but the evidence based on randomized controlled trials is scarce. This study evaluated the short-term (10-week) efficacy of a stabilization splint in subjects with recurrent secondary otalgia and active TMD treatment need using a randomized, controlled, double-blind design. Thirty-six subjects were randomly allocated to the two treatment groups: the stabilization splint and the control splint group. After 10 weeks' treatment, the intensity of secondary otalgia, measured on a VAS scale (from 0 to 100 mm), decreased statistically significantly in the stabilization splint group (t 2.12; P 0.006), but not in the control group. Improvement in active TMD treatment need in subjects showing moderate or severe signs and symptoms of TMD was reported significantly more often in the stabilization splint group than in the control splint group (χ2 5.71; P .017). A statistically significant decrease in the Helkimo clinical dysfunction index was seen in the subjects with stabilization splint (Z -2.63; P .009), but not in the subjects with control splint. The results indicate that the use of a stabilization splint is beneficial with regard to secondary otalgia and active TMD treatment need.  相似文献   
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