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991.
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Sunitinib is an oral tyrosine kinase inhibitor, which is indicated for the treatment of renal cell carcinoma and gastrointestinal stromal tumors. The authors report the case of a patient who underwent treatment for renal cell carcinoma and noted additional benefit by improvement in his psoriatic skin lesions. This may be attributed to the antiangiogenic activity of sunitinib by inhibition of vascular endothelial growth factor receptors.  相似文献   
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No studies have quantified the impact of pre-culture antibiotic use on the recovery of individual blood-borne pathogens or on population-level incidence estimates for Streptococcus pneumoniae. We conducted bloodstream infection surveillance in Thailand during November 2005–June 2008. Pre-culture antibiotic use was assessed by reported use and by serum antimicrobial activity. Of 35,639 patient blood cultures, 27% had reported pre-culture antibiotic use and 24% (of 24,538 tested) had serum antimicrobial activity. Pathogen isolation was half as common in patients with versus without antibiotic use; S. pneumoniae isolation was 4- to 9-fold less common (0.09% versus 0.37% by reported antibiotic use; 0.05% versus 0.45% by serum antimicrobial activity, P < 0.01). Pre-culture antibiotic use by serum antimicrobial activity reduced pneumococcal bacteremia incidence by 32% overall and 39% in children < 5 years of age. Our findings highlight the limitations of culture-based detection methods to estimate invasive pneumococcal disease incidence in settings where pre-culture antibiotic use is common.  相似文献   
994.

Background  

Parents are the ones who decide whether or not to participate in parent focused prevention trials. Their decisions may be affected by internal factors (e.g., personality, attitudes, sociodemographic characteristics) or external barriers. Some of these barriers are study-related and others are intervention-related. Internal as well as external barriers are especially important at the screening stage, which aims to identify children and families at risk and for whom the indicated prevention programs are designed. Few studies have reported their screening procedure in detail or analyzed differences between participants and dropouts or predictors of dropout. Rates of participation in prevention programs are also of interest and are an important contributor to the efficacy of a prevention procedure.  相似文献   
995.
Research on the relation of guilt to psychopathology is highly inconsistent. Some studies suggest that guilt contributes to psychopathology; others suggest that guilt serves a protective role. This review of 23 theory-based definitions of guilt and 25 measures of guilt suggests that a lack of conceptual clarity may be to blame. Measures of guilt do not correspond well to the definitions from which they derive. Many definitions and measures reflect the intrusion of extraneous constructs that could confound guilt research. Furthermore, definitions and measures of guilt change with developmental level. Nevertheless, two broad conceptualizations of guilt emerge. Central to both is a focus on one's action or inactions involving real or imagined moral transgressions. Distinguishing the two conceptualizations is whether or not guilt is inherently adaptive construct, generating remorse, augmenting a sense of responsibility, and motivating reparation. Recommendations for the definition and measurement of guilt are discussed.  相似文献   
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Sulforaphane (SFN), is an effective in vitro antagonist of ligand activation of the human pregnane and xenobiotic receptor (PXR). PXR mediated CYP3A4 up-regulation is implicated in adverse drug-drug interactions making identification of small molecule antagonists a desirable therapeutic goal. SFN is not an antagonist to mouse or rat PXR in vitro; thus, normal rodent species are not suitable as in vivo models for human response. To evaluate whether SFN can effectively antagonize ligand activation of human PXR in vivo, a three-armed, randomized, crossover trial was conducted with 24 healthy adults. The potent PXR ligand — rifampicin (300 mg/d) was given alone for 7 days in arm 1, or in daily combination with 450 μmol SFN (Broccoli Sprout extract) in arm 2; SFN was given alone in arm 3. Midazolam as an in vivo phenotype marker of CYP3A was administered before and after each treatment arm. Rifampicin alone decreased midazolam AUC by 70%, indicative of the expected increase in CYP3A4 activity. Co-treatment with SFN did not reduce CYP3A4 induction. Treatment with SFN alone also did not affect CYP3A4 activity in the cohort as a whole, although in the subset with the highest basal CYP3A4 activity there was a statistically significant increase in midazolam AUC (i.e., decrease in CYP3A4 activity). A parallel study in humanized PXR mice yielded similar results. The parallel effects of SFN between humanized PXR mice and human subjects demonstrate the predictive value of humanized mouse models in situations where species differences in ligand-receptor interactions preclude the use of a native mouse model for studying human ligand-receptor pharmacology.  相似文献   
999.
Due to health reasons, toxic metals must be removed from soils contaminated by mine tailings and smelter activities. The phytoremediation potential of Prosopis pubescens (screw bean mesquite) was examined by use of inductively-coupled plasma optical emission spectroscopy. Transmission electron microscopy was used to observe ultrastructural changes of parenchymal cells of leaves in the presence of copper. Elemental analysis was used to localize copper within leaves. A 600-ppm copper sulfate exposure to seedlings for 24 days resulted in 31,000 ppm copper in roots, 17,000 ppm in stems, 11,000 in cotyledons and 20 ppm in the true leaves. For a plant to be considered a hyperaccumulator, the plant must accumulate a leaf-to-root ratio <1. Screw bean mesquite exposed to copper had a leaf-to-root ratio of 0.355 when cotyledons were included. We showed that P. pubescens grown in soil is a hyperaccumulator of copper. We recommend that this plant should be field tested.  相似文献   
1000.
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