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1.
Zusammenfassung Die Beobachtung ernes Phytobezoars wird referiert, wo gastroskopisch die Diagnose gesichert und ein Trichobezoar ausgeschlossen werden konnte. Gastroskopisch fanden sich noch zwei kleine Magengeschwüre, diese waren röntgenologisch nicht nachzuweisen. Mit den Fällen des Schrifttums zusammen ist das die fünfte veröffentlichte gastroskopische Beobachtung über Phytobezoar.  相似文献   
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Polyclonal rabbit anticotinine antiserum, which can be used for biomonitoring nicotine uptake by the determination of cotinine in body fluids, was checked by a competitive ELISA for its cross-reactivity with nine nicotine metabolites. The highest percentage of relative crossreactivity (about 30%) was observed with trans-3-hydroxycotinine, a metabolite which is known to be excreted in 3-fold higher amounts than cotinine in the urine of human smokers. Therefore, it is possible that cotinine determinations performed by immunochemical methods — especially in urine — may yield overestimated cotinine concentrations.  相似文献   
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For identification of toxicological modes of action (MoAs) a database (MetaMap®Tox) was established containing plasma metabolome consisting of approximately 300 endogenous metabolites. Each five male and female Wistar rats per groups were treated with >500 reference compounds over a period of 28 days. More than 120 specific toxicity patterns of common metabolite changes associated with unique MoAs were established.  相似文献   
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As part of an ongoing dose reconstruction project, equivalent organ dose rates from photons and neutrons were estimated using the energy spectra measured in the central hall above the graphite reactor core located in the Russian Mayak Production Association facility. Reconstruction of the work environment was necessary due to the lack of personal dosimeter data for neutrons in the time period prior to 1987. A typical worker scenario for the central hall was developed for the Monte Carlo Neutron Photon-4B (MCNP) code. The resultant equivalent dose rates for neutrons and photons were compared with the equivalent dose rates derived from calculations using the conversion coefficients in the International Commission on Radiological Protection Publications 51 and 74 in order to validate the model scenario for this Russian facility. The MCNP results were in good agreement with the results of the ICRP publications indicating the modeling scenario was consistent with actual work conditions given the spectra provided. The MCNP code will allow for additional orientations to accurately reflect source locations.  相似文献   
7.
Accuracy of self-reported cancer-screening histories: a meta-analysis.   总被引:3,自引:0,他引:3  
BACKGROUND: Survey data used to study trends in cancer screening may overestimate screening utilization while potentially underestimating existing disparities in use. METHODS: We did a literature review and meta-analysis of validation studies examining the accuracy of self-reported cancer-screening histories. We calculated summary random-effects estimates for sensitivity and specificity, separately for mammography, clinical breast exam (CBE), Pap smear, prostate-specific antigen testing (PSA), digital rectal exam, fecal occult blood testing, and colorectal endoscopy. RESULTS: Sensitivity was highest for mammogram, CBE, and Pap smear (0.95, 0.94, and 0.93, respectively) and lowest for PSA and digital rectal exam histories (0.71 and 0.75). Specificity was highest for endoscopy, fecal occult blood testing, and PSA (0.90, 0.78, and 0.73, respectively) and lowest for CBE, Pap smear, and mammogram histories (0.26, 0.48, and 0.61, respectively). Sensitivity and specificity summary estimates tended to be lower in predominantly Black and Hispanic samples compared with predominantly White samples. When estimates of self-report accuracy from this meta-analysis were applied to cancer-screening prevalence estimates from the National Health Interview Survey, results suggested that prevalence estimates are artificially increased and disparities in prevalence are artificially decreased by inaccurate self-reports. CONCLUSIONS: National survey data are overestimating cancer-screening utilization for several common procedures and may be masking disparities in screening due to racial/ethnic differences in reporting accuracy.  相似文献   
8.
Enhanced cellular immune response to bovine beta-casein has been reported in patients with type 1 diabetes. In this study we aimed to establish beta-casein-specific T cell lines from newly diagnosed type 1 diabetic patients and to characterise these cell lines in terms of phenotype and epitope specificity. Furthermore, since sequence homologies exist between beta-casein and putative beta-cell autoantigens, reactivity to the latter was also investigated. T cell lines were generated from the peripheral blood of nine recent onset type 1 diabetic patients with different HLA-DQ and -DR genotypes, after stimulation with antigen pulsed autologous irradiated antigen presenting cells (APCs) and recombinant human interleukin-2 (rhIL-2). T cell line reactivity was evaluated in response to bovine beta-casein, to 18 overlapping peptides encompassing the whole sequence of beta-casein and to beta-cell antigens, including the human insulinoma cell line, CM, and a peptide from the beta-cell glucose transporter, GLUT-2. T cell lines specific to beta-casein could not be isolated from HLA-matched and -unmatched control subjects. beta-Casein T cell lines reacted to different sequences of the protein, however a higher frequency of T cell reactivity was observed towards the C-terminal portion (peptides B05-14, and B05-17 in 5/9 and 4/9 T cell lines respectively). Furthermore, we found that 1 out of 9 beta-casein-specific T cell lines reacted also to the homologous peptide from GLUT-2, and that 3 out of 4 of tested cell lines reacted also to extracts of the human insulinoma cell line, CM. We conclude that T cell lines specific to bovine beta-casein can be isolated from the peripheral blood of patients with type 1 diabetes; these cell lines react with multiple and different sequences of the protein particularly towards the C-terminal portion. In addition, reactivity of beta-casein T cell lines to human insulinoma extracts and GLUT-2 peptide was detected, suggesting that the potential cross-reactivity with beta-cell antigens deserves further investigation.  相似文献   
9.
Metabolite profiling (metabolomics) elucidates changes in biochemical pathways under various conditions, e.g., different nutrition scenarios or compound administration. BASF and metanomics have obtained plasma metabolic profiles of approximately 500 compounds (agrochemicals, chemicals and pharmaceuticals) from 28-day rat studies. With these profiles the establishment of a database (MetaMap®Tox) containing specific metabolic patterns associated with many toxicological modes of action was achieved. To evaluate confounding factors influencing metabolome patterns, the effect of fasting vs. non-fasting prior to blood sampling, the influence of high caloric diet and caloric restriction as well as the administration of corn oil and olive oil was studied for its influence on the metabolome. All mentioned treatments had distinct effects: triacylglycerol, phospholipids and their degradation product levels (fatty acids, glycerol, lysophosphatidylcholine) were often altered depending on the nutritional status. Also some amino acid and related compounds were changed. Some metabolites derived from food (e.g. alpha-tocopherol, ascorbic acid, beta-sitosterol, campesterol) were biomarkers related to food consumption, whereas others indicated a changed energy metabolism (e.g. hydroxybutyrate, pyruvate). Strikingly, there was a profound difference in the metabolite responses to diet restriction in male and female rats. Consequently, when evaluating the metabolic profile of a compound, the effect of nutritional status should be taken into account.  相似文献   
10.
Innate immune cells respond to invading microbes upon detection of pathogen-associated molecular patterns (PAMPS). PAMP-recognition machinery is evolutionarily conserved, allowing for characterization in model organisms. The model organism Dictyostelium discoideum can exist as single-celled amoebae, which phagocytize bacteria for nutrients. Although D. discoideum is used extensively to study phagocytosis, it has not been determined if D. discoideum detects bacterial PAMPs using pattern-recognition machinery. Here we show that D. discoideum mounts responses against the bacterial cell wall PAMP, lipopolysaccharide (LPS). Upon treatment with LPS or its active component Lipid A, D. discoideum cells more efficiently clear phagocytized bacteria. LPS-enhanced bactericidal activity appears dependent both on MAPK signaling pathways as well as on the D. discoideum toll/interleukin-1 receptor domain-containing protein, TirA. These findings indicate that pattern-recognition machinery required to detect and respond to bacterial PAMPs may be conserved in D. discoideum.  相似文献   
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