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Pancreatic pseudotumor in pancreas divisum: CT characteristics 总被引:1,自引:0,他引:1
P M Silverman L McVay R K Zeman B S Garra E G Grant M H Jaffe 《Journal of computer assisted tomography》1989,13(1):140-141
We report a case in which a focally spared area of pancreatic tissue in a gland otherwise replaced by fat created a "pseudomass" mimicking neoplasm on sonography and CT. The "pseudomass" appearance was related to the anomalous ductal anatomy in pancreas divisum. The spared area of pancreas creating a "pseudomass" was drained by the dorsal duct and the remainder of the pancreas that had undergone relative fatty replacement was drained by the ventral duct. 相似文献
6.
Murine tissues exposed to cytotoxic drugs display altered patterns of Candida albicans adhesion. 下载免费PDF全文
An ex vivo adhesion assay was used to examine the binding of Candida albicans yeast cells to tissues from mice treated with cytotoxic drugs such as lipopolysaccharide and the clinically used anticancer drugs doxorubicin, cisplatin, and vincristine. No major differences were observed in binding of the fungal cells to liver and kidney tissues from treated or untreated animals. All drug-treated spleens displayed altered patterns of C. albicans adhesion compared with the control group, with yeast cells bound not only to the marginal zone but also to the white and red pulp. Immunostaining for macrophages, which are proposed as the site of normal adhesion, showed no apparent differences between the control and the experimental spleens that could account for the change in adhesion patterns. Scanning electron microscopy images suggested that yeast binding to the white pulp of treated tissue is mediated through fibers, perhaps extracellular matrix components exposed as result of the cytotoxic treatment. Exposure of new attachment sites for C. albicans in treated tissues may facilitate initiation of infection. 相似文献
7.
Jolinda LD Schram Joost Oude Groeniger Merel Schuring Karin I Proper Sandra H van Oostrom Suzan JW Robroek Alex Burdorf 《Scandinavian journal of work, environment & health》2021,47(2):127
Objective:Using a novel mediation method that presents unbiased results even in the presence of exposure–mediator interactions, this study estimated the extent to which working conditions and health behaviors contribute to educational inequalities in self-rated health in the workforce.Methods:Respondents of the longitudinal Survey of Health, Ageing, and Retirement in Europe (SHARE) in 16 countries were selected, aged 50–64 years, in paid employment at baseline and with information on education and self-rated health (N=15 028). Education, health behaviors [including body mass index (BMI)] and working conditions were measured at baseline and self-rated health at baseline and two-year follow-up. Causal mediation analysis with inverse odds weighting was used to estimate the total effect of education on self-rated health, decomposed into a natural direct effect (NDE) and natural indirect effect (NIE).Results:Lower educated workers were more likely to perceive their health as poor than higher educated workers [relative risk (RR) 1.48, 95% confidence interval (CI) 1.37–1.60]. They were also more likely to have unfavorable working conditions and unhealthy behaviors, except for alcohol consumption. When all working conditions were included, the remaining NDE was RR 1.30 (95% CI 1.15–1.44). When BMI and health behaviors were included, the remaining NDE was RR 1.40 (95% CI 1.27–1.54). Working conditions explained 38% and health behaviors and BMI explained 16% of educational inequalities in health. Including all mediators explained 64% of educational inequalities in self-rated health.Conclusions:Working conditions and health behaviors explain over half of the educational inequalities in self-rated health. To reduce health inequalities, improving working conditions seems to be more important than introducing health promotion programs in the workforce. 相似文献
8.
The length of the optic nerves is a reflection of normal postnatal cranio-orbital development. Unilateral elongation of an optic nerve has been observed in two patients with orbital and skull base neoplasms. In the first case as compared to the patient's opposite, normal optic nerve, an elongated length of the involved optic nerve of 45 mm was present. The involved optic nerve in the second patient was 10 mm longer than the normal opposite optic nerve. The visual and extraocular function was preserved in the second patient. The first patient had only light perception in the affected eye. In this paper, the embryology, anatomy, and physiology of the optic nerve and its mechanisms of stretch and repair are discussed. 相似文献
9.
Characterization of xenobiotic-metabolizing enzymes and nitrosamine metabolism in the human esophagus 总被引:5,自引:2,他引:5
Smith TJ; Liao A; Wang LD; Yang GY; Starcic S; Philbert MA; Yang CS 《Carcinogenesis》1998,19(4):667-672
Esophageal cancer has been associated with tobacco smoking, and
nitrosamines are possible causative agents for this cancer. The present
study investigated the metabolism of the tobacco carcinogens N'-
nitrosonornicotine (NNN), 4-(methylnitrosamino)-1-(3-pyridyl)-1- butanone
(NNK), and N-nitrosodimethylamine (NDMA), as well as the presence of
xenobiotic-metabolizing enzymes in human esophageal tissues from
individuals in the United States and Huixian, Henan Province, China (a
high-risk area for esophageal cancer). All esophageal microsomal samples
activated NNN and the metabolic rate was 2-fold higher in the esophageal
samples from China than the USA. All microsomal samples activated NDMA.
However, most of the microsomal samples did not activate NNK.
Troleandomycin (an inhibitor of cytochrome P450 3A) decreased the formation
of NNN-derived keto acid by 20-26% in the esophageal microsomes. The
activities for NADPH: cytochrome c reductase, ethoxycoumarin O-deethylase,
NAD(P)H: quinone oxidoreductase and glutathione S-transferase were present
in the esophageal samples. Coumarin 7-hydroxylase (a representative
activity for P450 2A6) activity was not detected in the esophageal
microsomal samples. The activities for nitrosamine metabolism and
xenobiotic- metabolizing enzymes were decreased (by 30-50%) in the squamous
cell carcinomas compared with their corresponding non-cancerous mucosa. The
presence of activation and detoxification enzymes in the esophagus may play
an important role in determining the susceptibility of the esophagus to the
carcinogenic effect of nitrosamines. Our results suggest that P450s 3A4 and
2E1 are involved in the activation of NNN and NDMA, respectively, in the
human esophagus.
相似文献
10.
Jerrold Hill Janine M McVay Adrian Walter-Ginzburg Charles S Mills Janice Lewis Barbara E Lewis Howard Fillit 《Disease management》2005,8(4):223-234
The aim of this research was to examine the validity of a brief screen for cognitive impairment (BSCI) consisting of three questions administered by telephone (delayed recall, frequency of help with planning trips for errands, and frequency of help remembering to take medications). The study design was an age and gender matched case-control study. Seventy managed care members, 35 with dementia (cases) and 35 without dementia (controls), were assessed using BSCI embedded within a longer health assessment questionnaire commonly used in Medicare-managed care. A number of measures were used to examine validity of BSCI, including comparisons of the differences between cases and controls in BSCI scores, comparisons of the correlations between patient scores on BSCI and the Mini Mental Status Exam (MMSE, a common screening test for dementia) and the Alzheimer's Disease Assessment Scale (ADAS, a common dementia assessment test), and comparisons of the areas under the receiver operating characteristic (ROC) curves for the three instruments. BSCI scores for cases and controls were significantly different, as were their scores for the MMSE and ADAS. Scores on BSCI were significantly correlated with scores for the MMSE and ADAS using both the Kendall's tau-b and Spearman rank-order correlation; correlations ranged from 0.654 between BSCI and ADAS to -0.83 for the correlation between BSCI and the MMSE (p < 0.001 for both). The areas under the ROC curves ranged from 0.94 to 0.96 for the three tests, meaning that they were equally accurate in discriminating between demented and nondemented patients. BSCI, a brief telephone screen for cognitive impairment due to dementia, discriminates between demented patients and normal controls as well as two standard tests of dementia, and may be considered a valid screen for dementia. Compared to existing screening tests, it has the additional advantages of extreme brevity, and ease of administration and scoring by lay interviewers via telephone. The use of brief screening instruments for dementia, such as the one validated here, will be increasingly important for the effective management of dementia and other chronic diseases where dementia is a coexisting condition. 相似文献