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701.

Background

Thyroid Imaging Reporting and Data System (TIRADS) was developed to improve patient management and cost-effectiveness by avoiding unnecessary fine needle aspiration biopsy (FNAB) in patients with thyroid nodules. However, its clinical use is still very limited. Strain elastography (SE) enables the determination of tissue elasticity and has shown promising results for the differentiation of thyroid nodules.

Methods

The aim of the present study was to evaluate the interobserver agreement (IA) of TIRADS developed by Horvath et al. and SE. Three blinded observers independently scored stored images of TIRADS and SE in 114 thyroid nodules (114 patients). Cytology and/or histology was available for all benign (n = 99) and histology for all malignant nodules (n = 15).

Results

The IA between the 3 observers was only fair for TIRADS categories 2–5 (Coheńs kappa = 0.27,p = 0.000001) and TIRADS categories 2/3 versus 4/5 (ck = 0.25,p = 0.0020). The IA was substantial for SE scores 1–4 (ck = 0.66,p<0.000001) and very good for SE scores 1/2 versus 3/4 (ck = 0.81,p<0.000001). 92–100% of patients with TIRADS-2 had benign lesions, while 28–42% with TIRADS-5 had malignant cytology/histology. The negative-predictive-value (NPV) was 92–100% for TIRADS using TIRADS-categories 4&5 and 96–98% for SE using score ES-3&4 for the diagnosis of malignancy, respectively. However, only 11–42% of nodules were in TIRADS-categories 2&3, as compared to 58–60% with ES-1&2.

Conclusions

IA of TIRADS developed by Horvath et al. is only fair. TIRADS and SE have high NPV for excluding malignancy in the diagnostic work-up of thyroid nodules.  相似文献   
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The risk for Alzheimer's disease (AD) is associated with lifestyle factors, especially cigarette smoking. In this study we investigated the influence of smoking on the serum levels of folic acid, LDL and HDL in AD patients, patients with minimal cognitive impairment (MCI) and patients with major depression. We investigated a total of n = 374 patients in the diagnostic categories:, AD: n = 272, MCI: n = 60, Major depression: n = 42. We found significantly lower HDL levels in smokers and previous smokers in comparison to non-smokers, p<0,05. The LDL: HDL ratio in smokers was significant higher (+20%) compared to previous smokers and non-smokers, p < 0.05. The mean levels of folic acid were statistically significant (p<0.05) lower (-24%) in smokers compared to non-smokers. Patients with MCI and Alzheimer;s disease (and also major depression) who are "smokers" show serum levels of HDL and folic acid that are known to be strong risk factors for vascular damage and increased risk for vascular brain damage and impaired cognitive function. Therefore cessation of smoking, substitution with folate or statin therapy of smoking patients with MCI or AD might be beneficial to slow down further cognitive decline.  相似文献   
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We describe a localized proton magnetic resonance spectroscopy ((1)H-MRS) method for in vivo measurement of lipid composition in very small voxels (1.5 mm x 1.5 mm x 1.5 mm) in adipose tissue in mice. The method uses localized point-resolved spectroscopy to collect (1)H spectra from voxels in intra-abdominal white adipose tissue (WAT) and brown adipose tissue (BAT) deposits. Nonlinear least-squares fits of the spectra in the frequency domain allow for accurate calculation of the relative amount of saturated, monounsaturated, and polyunsaturated fatty acids. All spectral data are corrected for spin-spin relaxation. The data show BAT of NMRI mice to be significantly different from BAT of NMRI nu/nu mice in all aspects except for the fraction of monounsaturated fatty acids (FM); for WAT, only the FM is different. BAT and WAT of NMRI mice differ in the amount of saturated and di-unsaturated fatty acids. This method provides a potential tool for studying lipid metabolism in small animal models of disease during the initiation, progression, and manifestation of obesity-related disorders in vivo. Our results clearly demonstrate that localized (1)H-MRS of adipose tissue in vivo is possible at high spatial resolution with voxel sizes down to 3.4 ml.  相似文献   
708.
Lipase from Candida rugosa was loaded into an amphiphilic polymer co-network (APCN) composed of the chiral poly[(R)-N-(1-hydroxybutan-2-yl) acrylamide] [P-(R)-HBA] and P-(S)-HBA, respectively, linked by poly(dimethylsiloxane). The nanophase-separated amphiphilic morphology affords a 38,000-fold activation of the enzyme in the esterification of 1-phenylethanol with vinyl acetate. Further, the enantioselectivity of the entrapped lipase was influenced by the configuration of the chiral, hydrophilic polymer matrix. While the APCN with the (S)-configuration of the APCN affords 5.4 faster conversion of the (R)-phenylethanol compared to the respective (S)-enantiomer, the (R)-APCN allows an only a 2.8 faster conversion of the (R)-enantiomer of the alcohol. Permeation-experiments reveal that the enantioselectivity of the reaction is at least partially caused by specific interactions between the substrates and the APCN.  相似文献   
709.
A combination of high ionic conductivity and facile processing suggest that sulfide‐based materials are promising solid electrolytes that have the potential to enable Li metal batteries. Although the Li2S‐P2S5 (LPS) family of compounds exhibit desirable characteristics, it is known that Li metal preferentially propagates through microstructural defects, such as particle boundaries and/or pores. Herein, it is demonstrated that a near theoretical density (98% relative density) LPS 75‐25 glassy electrolyte exhibiting high ionic conductivity can be achieved by optimizing the molding pressure and temperature. The optimal molding pressure reduces porosity and particle boundaries while preserving the preferred amorphous structure. Moreover, molecular rearrangements and favorable Li coordination environments for conduction are attained. Consequently, the Young's Modulus approximately doubles (30 GPa) and the ionic conductivity increases by a factor of five (1.1 mS cm?1) compared to conventional room temperature molding conditions. It is believed that this study can provide mechanistic insight into processing‐structure‐property relationships that can be used as a guide to tune microstructural defects/properties that have been identified to have an effect on the maximum charging current that a solid electrolyte can withstand during cycling without short‐circuiting.  相似文献   
710.

Introduction

Reporting guidelines (e.g. CONSORT) have been developed as tools to improve quality and reduce bias in reporting research findings. Trial registration has been recommended for countering selective publication. The International Committee of Medical Journal Editors (ICMJE) encourages the implementation of reporting guidelines and trial registration as uniform requirements (URM). For the last two decades, however, biased reporting and insufficient registration of clinical trials has been identified in several literature reviews and other investigations. No study has so far investigated the extent to which author instructions in psychiatry journals encourage following reporting guidelines and trial registration.

Method

Psychiatry Journals were identified from the 2011 Journal Citation Report. Information given in the author instructions and during the submission procedure of all journals was assessed on whether major reporting guidelines, trial registration and the ICMJE’s URM in general were mentioned and adherence recommended.

Results

We included 123 psychiatry journals (English and German language) in our analysis. A minority recommend or require 1) following the URM (21%), 2) adherence to reporting guidelines such as CONSORT, PRISMA, STROBE (23%, 7%, 4%), or 3) registration of clinical trials (34%). The subsample of the top-10 psychiatry journals (ranked by impact factor) provided much better but still improvable rates. For example, 70% of the top-10 psychiatry journals do not ask for the specific trial registration number.

Discussion

Under the assumption that better reported and better registered clinical research that does not lack substantial information will improve the understanding, credibility, and unbiased translation of clinical research findings, several stakeholders including readers (physicians, patients), authors, reviewers, and editors might benefit from improved author instructions in psychiatry journals. A first step of improvement would consist in requiring adherence to the broadly accepted reporting guidelines and to trial registration.  相似文献   
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