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Background Itching is a cardinal symptom of atopic dermatitis (AD). Objective The study aim was to evaluate the relationships between pruritus and stress, health‐related quality of life (HRQoL) and depression in adult patients with AD. Methods Eight‐nine patients (30 men and 59 women) with AD were included. Demographic and clinical data were collected. The intensity of pruritus was assessed according to the 10‐point Visual Analogue Scale (VAS) and the 4‐Item Itch Questionnaire, HRQoL according to Dermatology Life Quality Index, and depression symptoms with Beck’s Depression Inventory (BDI). Stress experienced by patients was evaluated with Social Readjustment Rating Scale and Stress Self‐assessment Scale. Results The mean intensity of pruritus according to VAS was 7.9 ± 2.2 points, and according to 4‐Item Itch Questionnaire 14.0 ± 4.4 points. The intensity of pruritus was related to the stress experienced by the patients prior to disease exacerbation (ρ = 0.37, P < 0.001). A significant correlation between pruritus and HRQoL was also found (VAS: ρ = 0.5, P < 0.001, 4‐Item Itch Questionnaire: ρ = 0.5, P < 0.001) as well as between pruritus and BDI (VAS: ρ = 0.44, P < 0.001, 4‐Item Itch Questionnaire: ρ = 0.51, P < 0.001). Patients with symptoms suggesting depression had more intense pruritus compared with the rest of patients (VAS: 9.1 ± 1.6 vs. 7.6 ± 2.2 points, P = 0.004; 4‐Item Itch Questionnaire: 17.3 ± 2.5 vs. 13.1 ± 4.4 points, P < 0.001). Conclusions Itching intensity in AD plays an important role in determining patients’ psychosocial well‐being. Patients with atopic dermatitis require an effective, long‐term antipruritic therapy to improve their QoL and reduce the potential risk of depression.  相似文献   
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Walter Reich 《Psychiatry》2013,76(4):400-403
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Visualizing myelin in human brain may help the study of diseases such as multiple sclerosis. Previous studies based on T1 and T2 relaxation contrast have suggested the presence of a distinct water pool that may report directly on local myelin content. Recent work indicates that T2* contrast may offer particular advantages over T1 and T2 contrast, especially at high field. However, the complex mechanism underlying T2* relaxation may render interpretation difficult. To address this issue, T2* relaxation behavior in human brain was studied at 3 and 7 T. Multiple gradient echoes covering most of the decay curve were analyzed for deviations from mono‐exponential behavior. The data confirm the previous finding of a distinct rapidly relaxing signal component (T2* ~ 6 ms), tentatively attributed to myelin water. However, in extension to previous findings, this rapidly relaxing component displayed a substantial resonance frequency shift, reaching 36 Hz in the corpus callosum at 7 T. The component's fractional amplitude and frequency shift appeared to depend on both field strength and fiber orientation, consistent with a mechanism originating from magnetic susceptibility effects. The findings suggest that T2* contrast at high field may be uniquely sensitive to tissue myelin content and that proper interpretation will require modeling of susceptibility‐induced resonance frequency shifts. Magn Reson Med, 2011. © 2011 Wiley‐Liss, Inc.  相似文献   
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Illicit drug profiling performed by forensic laboratories assists law enforcement agencies through providing information about chemical and/or physical characteristics of seized specimens. In this article, a model was developed for the comparison of seized cocaine based on retrospective analysis of data generated from ultrahigh performance liquid chromatography with time-of-flight mass spectrometry (UHPLC-TOF-MS) comprehensive drug screening. A nontargeted approach to discover target compounds was employed, which generated 53 potential markers using data from cocaine positive samples. Twelve marker compounds were selected for the development of the final profiling model. The selection included a mixture of commonly used cocaine profiling targets and other cocaine-related compounds. Combinations of pretreatments and comparison metrics were assessed using receiver operating characteristic curves to determine the combination with the best discrimination between linked and unlinked populations. Using data from 382 linked and 34,519 unlinked distances, a classification model was developed using a combination of the standardization and normalization transformations with Canberra distance, resulting in a linked cut-off with a 0.5% false positive rate. The present study demonstrates the applicability of retrospectively developing a cocaine profiling model using data generated from UHPLC-TOF-MS nontargeted drug screening without pre-existing information about cocaine impurities. The developed workflow was not specific to cocaine and thus could potentially be applied to any seized drug in which there are both sufficient data and impurities present.  相似文献   
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Using data from The Collaborative Study on the Genetics of Alcoholism, we compare direct interview diagnoses of alcohol dependence to those obtained by history from family members. Using a requirement of three or more positive implications by history, the specificity, sensitivity, and positive predictive values are 98%, 39%, and 45%, respectively.
A logistic analysis found the gender of the relative and alcoholism in the informant to be significant, but not the gender of the informant. The partial odds ratio of a diagnosis at interview associated with a positive family history diagnosis was 13.6. The relationship between the informant and relative was significant, with negative reports from an offspring or mate more influential than a negative report from a parent or second-degree relative.
We derived a recursive equation to combine a variable number of family history reports, wherein the probabilities associated with a single report are computed from the logistic analysis. This permits the use of family history information both as a proxy for an uninterviewed relative, as well as a second source of information to be used in the analysis of genetic family data.  相似文献   
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