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1.
Obesity is a risk factor for colorectal cancer. Yet, some research indicates that weight-reducing bariatric surgery also increases colorectal cancer risk. Our study was undertaken because current evidence examining bariatric surgery and risk of colorectal cancer is limited and inconsistent. This population-based cohort study included adults with a documented obesity diagnosis in Denmark, Finland, Iceland, Norway or Sweden in 1980–2015. The incidence of colorectal cancer in participants with obesity who had and had not undergone bariatric surgery was compared to the incidence in the corresponding background population by calculating standardized incidence ratios (SIR) with 95% confidence intervals (CI). Additionally, operated and nonoperated participants with obesity were compared using multivariable Cox regression, providing hazard ratios (HR) with 95% CIs adjusted for confounders. Among 502,772 cohort participants with an obesity diagnosis, 49,931(9.9%) underwent bariatric surgery. The overall SIR of colon cancer was increased after bariatric surgery (SIR 1.56; 95% CI 1.28–1.88), with higher SIRs ≥10 years postsurgery. The overall HR of colon cancer in operated compared to nonoperated participants was 1.13 (95% CI 0.92–1.39) and 1.55 (95% CI 1.04–2.31) 10–14 years after bariatric surgery. Bariatric surgery did not significantly increase the risk of rectal cancer (SIR 1.14, 95% CI 0.83–1.52; HR 1.08, 95% CI 0.79–1.49), but the risk estimates increased with longer follow-up periods. Our study suggests that bariatric surgery is associated with an increased risk of colon cancer, while the support for an increased risk of rectal cancer was weaker.  相似文献   
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Using hierarchical cluster analysis, applied to 47 cases of Guillain-Barre Syndrome (GBS) incident in South-West Stockholm (SWS) during the period from January 1973 to June 1992, we identified three major clinicoepidemiological subgroups. The first subgroup, 25.5% of the cases (26.7 ± 6.7 years), recorded a peak incidence at ages 20–29 years and presented significant differences from other subgroups, a high proportion of cases with onset at low age preceded by respiratory infection (83.3%) and with normal motor conduction velocity (50.0%). Also found, were less affected biological parameters, a rapidly progressive course and independence in gait at one month after onset. A second subgroup, 27.7% of cases, was severely affected, clinically and functionally. It consisted predominantly of young individuals (22.7 ± 11.1 years), with a high incidence (69.2% of cases) in autumn. A third subgroup, comprising 40.47; of cases, was older (61.1 ± 11.0 years) and, in general, also severely affected. The incidence of this form appeared to be invariant with time.  相似文献   
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The technique of positron emission tomography (PET) is described. PET is an in vivo imaging and quantitative technique which allows the visualization of various functional and biochemical parameters. PET is a tracer technique in which bioactive tracer substances are labelled with short-lived positron emitting radionuclides. The most important of these are 15O, 13N, 11C and 18F with decay times ranging from 2 min to 2 h. The radiolabeled substance is injected intravenously and the distribution, uptake and binding are registered externally with the PET camera using of the order of 4 000 small detectors. The camera produces simultaneously 15 tomographic slices in which the absolute concentration of the tracer substance can be measured. Using a dynamic imaging sequence starting after the injection of the tracer, the dynamics of the tracer uptake is recorded and can be used to deduce functional parameters, such as perfusion flow, tracer distribution, binding to receptor or enzyme systems, etc. depending on the choice of tracer substance. The great versatility of PET and its potential of direct noninvasive study of tumor function will make it a very important clinical and research tool in oncology. With the choice of substances selective for a certain aspect of a tumor's biochemistry the potential opens for a better diagnosis, improved differential diagnosis and, especially with the use of metabolic tracers, an improved possibility to evaluate the response to treatment.  相似文献   
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For a PET agent to be successful as a biomarker in early clinical trials of new anticancer agents, some conditions need to be fulfilled: the selected tracer should show a response that is related to the antitumoral effects, the quantitative value of this response should be interpretable to the antitumoral action, and the timing of the PET scan should be optimized to action of the drug. These conditions are not necessarily known at the start of a drug-development program and need to be explored. We proposed a translational imaging activity in which experiments in spheroids and later in xenografts are coupled to modeling of growth inhibition and to the related changes in the kinetics of PET tracers and other biomarkers. In addition, we demonstrated how this information can be used for planning clinical trials. METHODS: The first part of this concept is illustrated in a spheroid model with BT474 breast cancer cells treated with the heat shock protein 90 (Hsp90) inhibitor NVP-AUY922. The growth-inhibitory effect after a pulse treatment with the drug was measured with digital image analysis to determine effects on volume with high accuracy. The growth-inhibitory effect was described mathematically by a combined E(max) and time course model fitted to the data. The model was then used to simulate a once-per-week treatment; in these experiments the uptake of the PET tracers (18)F-FDG and 3'-deoxy-3'-(18)F-fluorothymidine ((18)F-FLT) was determined at different doses and different time points. RESULTS: A drug exposure of 2 h followed by washout of the drug from the culture medium generated growth inhibition that was maximal at the earliest time point of 1 d and decreased exponentially with time during 10-12 d. The uptake of (18)F-FDG per viable tumor volume was minimally affected by the treatment, whereas the (18)F-FLT uptake decreased in correlation with the growth inhibition. CONCLUSION: The study suggests a prolonged action of the Hsp90 inhibitor that supports a once-per-week schedule. (18)F-FLT is a suitable tracer for the monitoring of effect, and the (18)F-FLT PET study might be performed within 3 d after dosing.  相似文献   
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Beta-interferon (IFN-β) is a promising treatment in multiple sclerosis (MS), reducing the exacerbation rate and MRI lesion burden, as well as the disease progression in relapsing-remitting MS. IFN-β was originally defined by its antiviral effects, but the interest has recently been focused on its immunomodulatory properties. Myelin basic protein (MBP) is one of several autoantigens considered to be the target for autoaggressive immune responses, which eventually might lead to the development of MS. To study in-vitro effects of IFN-β1b on MBP induced cytokine expression, mRNA for the Th1 cytokines IFN-γ and TNF-α, the Th2 related IL-4 and IL-6, the cytolytic perforin and the immune response downregulating TGF-β was measured with in situ hybridization after culture of blood mononuclear cells (MNC) in the presence and absence of MBP. Numbers of cells expressing IFN-γ, TNF-α, perforin and IL-4 mRNA were significantly suppressed after culture with 10 U/ml IFN-β1b. No such effect was seen on MBP induced IL-6 or TGF-β mRNA expression. These observations suggest that one of the major effects of IFN-β1b is the induction of a shift in the cytokine mRNA profile towards a more immunosuppressive pattern. In parallel in vitro tests, the control substance dexametasone (40 μg/ml) reduced the numbers of cells expressing mRNA for all cytokines under study with the exception of TGF-β, to an extent equal to or even more pronounced than IFN-β1b.  相似文献   
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Under designations like small areas action research and intervention, directed ‘ground-up’ health promotion and prevention in the population form an important part of the ongoing medical systems development. There is recent evidence of the success of community intervention against cardiovascular disease. In osteoporosis, however, there is still a lack of conclusive data on both the logics and logistics of such an approach. Since 1988, a county health policy program has been formulated and implemented in Östergötland, Sweden, following the principles and guidelines of the WHO HFA 2000 declaration. Vadstena (n ? 7,600) was chosen for a local and generalizable osteoporosis prevention project mediated by the primary care organization by means of health promotion and education in the community. In the present report we emphasize that community intervention is an important new advancement of the medical systems, where the basic research questions include operational and management aspects as equally vital and measurable requisites and results as other performance and outcome variables. We found that a community intervention trial against osteoporosis is both motivated and feasible and in this report wish to provide evidence on these crucial issues of logics and logistics.  相似文献   
9.
Fifty alcoholics who attended a 2-year out-patient treatment program with standardized evaluations every third month were followed-up 2 years after completion of the program. One patient refused to be followed-up and four were dead. Corroboration was available in 78% of the cases. The number of abuse days from the second half-year of therapy and forward was strongly related to the number of abuse days during the follow-up period as were ratings both of drinking goal fulfillment and fulfillment of other treatment goals at termination of the treatment period. On the contrary initial characteristics and background data as well as the number of abuse days during the first half-year were not related to number of abuse days during the follow-up period. Our findings indicate that improvement during long term out-patient treatment for alcoholism is stable during the following 2 years with a socially stable sample.  相似文献   
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