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排序方式: 共有588条查询结果,搜索用时 718 毫秒
1.
Hanna Lee Mary K. Tan Andrew T. Yan Paul Angaran Paul Dorian Claudia Bucci Jean C. Gregoire Alan D. Bell Martin S. Green Peter L. Gross Allan Skanes Charles R. Kerr L. Brent Mitchell Jafna L. Cox Vidal Essebag Brett Heilbron Krishnan Ramanathan Carl Fournier Shaun G. Goodman 《The Canadian journal of cardiology》2019,35(2):160-168
Background
Physicians treating nonvalvular atrial fibrillation (AF) assess stroke and bleeding risks when deciding on anticoagulation. The agreement between empirical and physician-estimated risks is unclear. Furthermore, the association between patient and physician sex and anticoagulation decision-making is uncertain.Methods
We pooled data from 2 national primary care physician chart audit databases of patients with AF (Facilitating Review and Education to Optimize Stroke Prevention in Atrial Fibrillation and Coordinated National Network to Engage Physicians in the Care and Treatment of Patients with Atrial Fibrillation Chart Audit) with a combined 1035 physicians (133 female, 902 male) and 10,927 patients (4567 female and 6360 male).Results
Male physicians underestimated stroke risk in female patients and overestimated risk in male patients. Female physicians estimated stroke risk well in female patients but underestimated the risk in male patients. Risk of bleeding was underestimated in all. Despite differences in risk assessment by physician and patient sex, > 90% of patients received anticoagulation across all subgroups. There was modest agreement between physician estimated and calculated (ie, CHADS2 score) stroke risk: Kappa scores were 0.41 (0.35-0.47) for female physicians and 0.34 (0.32-0.36) for male physicians.Conclusions
Our study is the first to examine the association between patient and physician sex influences and stroke and bleeding risk estimation in AF. Although there were differences in agreement between physician estimated stroke risk and calculated CHADS2 scores, these differences were small and unlikely to affect clinical practice; further, despite any perceived differences in the accuracy of risk assessment by sex, most patients received anticoagulation. 相似文献2.
We report five cases of asymptomatic patients with persistently abnormal liver function tests in whom copper metabolism abnormalities resulted in a misleading suspicion of Wilson's disease. Ceruloplasmin levels assessed by nephelometric immunoassay, single radial immunodiffusion and the enzymatic method averaged 53.8, 61 and 52.8% of the mean value obtained in age- and sex-matched controls (p less than 0.001). Twenty-four-hour urinary copper excretion was higher than the normal range in three instances. Four patients exhibited hypertriglyceridemia. Liver histology showed fatty change with or without sinusoidal fibrosis. Electron microscopic examination unexpectedly disclosed mitochondrial and lysosomal changes identical to those described in Wilson's disease. The present observations indicate that biochemical and ultrastructural changes suggestive for Wilson's disease may be observed in the absence of increased liver copper content. Whether such cases represent isolated cases of heterozygosity for the Wilson's disease gene remains to be elucidated. 相似文献
3.
Disposition and pharmacokinetics of [14C]finasteride after oral administration in humans. 总被引:2,自引:0,他引:2
J R Carlin P H?glund L O Eriksson P Christofalo S L Gregoire A M Taylor K E Andersson 《Drug metabolism and disposition》1992,20(2):148-155
The disposition of [14C]finasteride, a competitive inhibitor of steroid 5 alpha-reductase, was investigated after oral administration of 38.1 mg (18.4 microCi) of drug in six healthy volunteers. Plasma, urine, and feces were collected for 7 days and assayed for total radioactivity. Concentrations of finasteride and its neutral metabolite, omega-hydroxyfinasteride (monohydroxylated on the t-butyl side chain), in plasma and urine were determined by HPLC assay. Mean excretion of radioactivity equivalents in urine and feces equaled 39.1 +/- 4.7% and 56.8 +/- 5.0% of the dose, respectively. The mean peak plasma concentrations reached for total radioactivity (ng equivalents), finasteride, and omega-hydroxyfinasteride were 596.5 +/- 88.3, 313.8 +/- 99.4, and 73.7 +/- 11.8 ng/ml, respectively, at approximately 2 hr; the mean terminal half-life for drug and metabolite was 5.9 +/- 1.3 and 8.4 +/- 1.7 hr, respectively. Of the 24-hr plasma radioactivity, 40.9% was finasteride, 11.8% was the neutral metabolite, and 26.7% was characterized as an acidic fraction of radioactivity. Binding of [14C]finasteride to plasma protein was extensive (91.3 to 89.8%), with a trend suggesting concentration dependency (range 0.02 to 2 micrograms/ml). Little of the dose was excreted in urine as parent (0.04%) or omega-hydroxyfinasteride (0.4%). Urinary excretion of radioactivity was largely in the form of acidic metabolite(s)--18.4 +/- 1.7% of the dose was eliminated as the omega-monocarboxylic acid metabolite. Finasteride was scarcely excreted unchanged in feces. In humans, finasteride is extensively metabolized through oxidative pathways.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
4.
Cross-antigenicity of horse serum albumin with dog and cat albumins: study of three short peptides with significant inhibitory activity towards specific human IgE and IgG antibodies. 总被引:2,自引:0,他引:2
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Horse serum albumin is present in the near vicinity of the animal, while dog and cat serum albumins are very common allergens present in house dust. Human patients clinically defined as allergic to horse could react with horse serum albumin by means of IgE or IgG antibodies. Studies regarding the specificities of these antibodies by inhibition enzyme-linked immunosorbent assay (ELISA) and depletion experiments have demonstrated that they are directed against dog serum albumin and cross-react not only with horse serum albumin but with other serum albumins from different origins. To investigate these observations further, we isolated and characterized three tryptic peptides (P1, P2 and P3) from horse serum albumin. The peptide P1 contains loops 1 and 2 of the first domain, P2 is derived from loop 4 of the second domain, and P3 contains the disulphide loop 9 of the third domain. These were able to inhibit the binding of the patients' IgE and IgG antibodies to horse albumin as well as to dog and cat serum albumins. This indicates that these peptides are involved in the observed cross-reactions. They also shared common epitopes, as revealed by human IgE antibodies. After reduction and alkylation, they totally lost their inhibitory capacity, suggesting that the intra-chain disulphide bridges, essential for the preservation of the loop structure, probably maintain their allergenic/antigenic reactivity. 相似文献
5.
Rapid eye movements (REMs), EEG alpha, and tonic heart rate (HR) were measured during 6 types of cognitive tasks—imagining a liked person, suppressing thoughts of the person, searching one's mind for alternative solutions, arithmetic involving little concentration, problems involving high concentration, and choosing a preferred activity. The latter 3 required verbalization, the former 3 did not. Only suppression and search did not differ significantly from each other on at least one physiological variable. Imagining, suppression, and search yielded few REMs, high alpha, and low HR. High concentration yielded many REMs, low alpha, and high HR. Choice yielded many REMs, low alpha, and intermediate HR. Low concentration yielded few REMs, low alpha, and high HR. Suppression produced somewhat less alpha than imagining but did not differ significantly in REMs. 相似文献
6.
Tight junction proteins claudin-3 and claudin-4 are frequently overexpressed in ovarian cancer but not in ovarian cystadenomas. 总被引:18,自引:0,他引:18
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9.
Audrey L. Begun Sheila M. Barnhart Thomas K. Gregoire Edward G. Shepherd 《Social work in health care》2014,53(5):446-459
The Empowering Mothers to Establish Smoke-free Homes (EMESH) project developed in response to an interdisciplinary health team seeking effective interventions for reducing/eliminating the environmental tobacco smoke exposure of infants with compromised respiratory status. Two study phases that informed the EMESH intervention design are described. Phase I involved semi-structured interviews with 20 caretakers of infants diagnosed with Bronchopulmonary Dysplasia (BPD). In Phase II, 75 randomly selected medical records of infants with BPD were reviewed to explore the family demographics and staff behavior regarding environmental tobacco smoke (ETS) interventions. Interview results suggest that families are open to partnering with social workers and interdisciplinary team members in addressing infants’ ETS exposure, families’ unique circumstances indicate a need for tailored interventions, and the use of self-efficacy and decisional balance tools are feasible options. Results from the medical records review indicate that many families are economically vulnerable and reside in regions where smoking is common. There is a paucity of staff documentation regarding ETS conversations and interventions, indicating that these conversations may not take place. Together these results suggest a two-pronged approach in the next phases of EMESH: staff training in hosting and documenting ETS conversations and a tailored, parent-driven set of intervention options. 相似文献
10.
Annelies Suetens Marjan Moreels Roel Quintens Els Soors Jasmine Buset Sabina Chiriotti Kevin Tabury Vincent Gregoire Sarah Baatout 《Journal of radiation research》2015,56(1):11-21
Hadrontherapy is an advanced form of radiotherapy that uses beams of charged particles (such as protons and carbon ions). Compared with conventional radiotherapy, the main advantages of carbon ion therapy are the precise absorbed dose localization, along with an increased relative biological effectiveness (RBE). This high ballistic accuracy of particle beams deposits the maximal dose to the tumor, while damage to the surrounding healthy tissue is limited. Currently, hadrontherapy is being used for the treatment of specific types of cancer. Previous in vitro studies have shown that, under certain circumstances, exposure to charged particles may inhibit cell motility and migration. In the present study, we investigated the expression of four motility-related genes in prostate (PC3) and colon (Caco-2) cancer cell lines after exposure to different radiation types. Cells were irradiated with various absorbed doses (0, 0.5 and 2 Gy) of accelerated 13C-ions at the GANIL facility (Caen, France) or with X-rays. Clonogenic assays were performed to determine the RBE. RT-qPCR analysis showed dose- and time-dependent changes in the expression of CCDC88A, FN1, MYH9 and ROCK1 in both cell lines. However, whereas in PC3 cells the response to carbon ion irradiation was enhanced compared with X-irradiation, the effect was the opposite in Caco-2 cells, indicating cell-type–specific responses to the different radiation types. 相似文献