379 research outputs found
The Value of Autofluorescence Bronchoscopy Combined with White Light Bronchoscopy Compared with White Light Alone in the Diagnosis of Intraepithelial Neoplasia and Invasive Lung Cancer: A Meta-Analysis
ObjectiveTo compare the accuracy of autofluorescence bronchoscopy (AFB) combined with white light bronchoscopy (WLB) versus WLB alone in the diagnosis of lung cancer.MethodsThe Ovid, PubMed, and Google Scholar databases from January 1990 to October 2010 were searched. Two reviewers independently assessed the quality of the trials and extracted data. The relative risk for sensitivity and specificity on a per-lesion basis of AFB + WLB versus WLB alone to detect intraepithelial neoplasia and invasive cancer were pooled by Review Manager.ResultsTwenty-one studies involving 3266 patients were ultimately analyzed. The pool relative sensitivity on a per-lesion basis of AFB + WLB versus WLB alone to detect intraepithelial neoplasia and invasive cancer was 2.04 (95% confidence interval [CI] 1.72–2.42) and 1.15 (95% CI 1.05–1.26), respectively. The pool relative specificity on a per-lesion basis of AFB + WLB versus WLB alone was 0.65 (95% CI 0.59–0.73).ConclusionsAlthough the specificity of AFB + WLB is lower than WLB alone, AFB + WLB seems to significantly improve the sensitivity to detect intraepithelial neoplasia. However, this advantage over WLB alone seems much less in detecting invasive lung cancer
Self‐Sacrificial Template‐Directed Synthesis of Metal–Organic Framework‐Derived Porous Carbon for Energy‐Storage Devices
Metal–organic framework (MOF)‐derived carbon materials exhibit large surface areas, but dominant micropore characteristics and uncontrollable dimensions. Herein, we propose a self‐sacrificial template‐directed synthesis method to engineer the porous structure and dimensions of MOF‐derived carbon materials. A porous zinc oxide (ZnO) nanosheet solid is selected as the self‐sacrificial template and two‐dimensional (2D) nanostructure‐directing agent to prepare 2D ZIF‐8‐derived carbon nanosheets (ZCNs). The as‐prepared ZCN materials exhibit a large surface area with hierarchical porosity. These intriguing features render ZCN materials advanced electrode materials for electrochemical energy‐storage devices, demonstrating large ion‐accessible surface area and high ion‐/electron‐transport rates. This self‐sacrificial template‐directed synthesis method offers new avenues for rational engineering of the porous structure and dimensions of MOF‐derived porous carbon materials, thus exploiting their full potential for electrochemical energy‐storage devices.On the surface: A self‐sacrificial template‐directed synthesis method is proposed to engineer the porosity and dimensions of MOF‐derived carbon materials. By using a porous nanosheet solid as the self‐sacrificial template and two‐dimensional (2D) nanostructure‐directing agent, 2D ZIF‐8‐derived carbon nanosheets are prepared, which exhibit a large ion‐accessible surface area and rapid ion transport as the electrode materials for electrochemical energy‐storage devices.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/137193/1/celc201500536-sup-0001-misc_information.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/137193/2/celc201500536.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/137193/3/celc201500536_am.pd
Significant change in the electronic behavior associated with structural distortions in the single crystalline SrAg4As2
We report a combined study of transport and thermodynamic measurements on the
layered pnictide material SrAg4As2. Upon cooling, a drop in electrical and Hall
resistivity, a jump in heat capacity and an increase in susceptibility and
magnetoresistance (MR) are observed around 110 K. These observations suggest
that non-magnetic phase transitions emerge at around 110 K, that are likely
associated with structural distortions. In sharp contrast with the
first-principles calculations based on the crystal structure at room
temperature, quantum oscillations reveal small Fermi pockets with light
effective masses, suggesting a significant change in the Fermi surface topology
caused by the low temperature structural distortion. No superconductivity
emerges in SrAgAs down to 2 K and under pressures up to 2.13 GPa;
instead, the low temperature structural distortion increases linearly with
temperature at a rate of ~13 K/GPa above 0.89 GPa
Current research in perineural invasion of cholangiocarcinoma
<p>Abstract</p> <p>Background</p> <p>Perineural invasion is a common path for cholangiocarcinoma (CCA) metastasis, and it is highly correlated with postoperative recurrence and poor prognosis. It is often an early event in a disease that is commonly diagnosed in advanced stages, and thus it could offer a timely therapeutic and diagnostic target if better understood. This article systematically reviews the progress of CCA neural invasion-related molecules.</p> <p>Methods</p> <p>Studies were identified by searching MEDLINE and PubMed databases for articles from January 1990 to December 2009, using the keywords "cholangiocarcinoma," "perineural invasion," "nerve growth factor"(NGF), "neural cell adhesion molecule" (NCAM), "matrix metalloproteinase"(MMP), "neurotransmitter," "acetylcholine" (Ach), and "transforming growth factor" (TGF)." Additional papers and book chapters were identified by a manual search of references from the key articles.</p> <p>Results</p> <p>From above we found that the molecules NGF, NCAM, MMP, Ach and TGF may have prognostic significance in, and offer clues to the mechanism of CCA neural invasion.</p> <p>Conclusions</p> <p>Cholangiocarcinoma's increasing worldwide incidence is especially poignant in view of both the lacking effective therapies, and the fact that it is commonly diagnosed in advanced stages. As CCA neural invasion often appears early, more complete characterization of its molecular pathology could lead to the identification of targets for the diagnosis and therapy of this devastating malignancy.</p
An Algorithm for Identifying Novel Targets of Transcription Factor Families: Application to Hypoxia-inducible Factor 1 Targets
Efficient and effective analysis of the growing genomic databases requires the development of adequate computational tools. We introduce a fast method based on the suffix tree data structure for predicting novel targets of hypoxia-inducible factor 1 (HIF-1) from huge genome databases. The suffix tree data structure has two powerful applications here: one is to extract unknown patterns from multiple strings/sequences in linear time; the other is to search multiple strings/sequences using multiple patterns in linear time. Using 15 known HIF-1 target gene sequences as a training set, we extracted 105 common patterns that all occur in the 15 training genes using suffix trees. Using these 105 common patterns along with known subsequences surrounding HIF-1 binding sites from the literature, the algorithm searches a genome database that contains 2,078,786 DNA sequences. It reported 258 potentially novel HIF-1 targets including 25 known HIF-1 targets. Based on microarray studies from the literature, 17 putative genes were confirmed to be upregulated by HIF-1 or hypoxia inside these 258 genes. We further studied one of the potential targets, COX-2, in the biological lab; and showed that it was a biologically relevant HIF-1 target. These results demonstrate that our methodology is an effective computational approach for identifying novel HIF-1 targets
Acetonitriletriaqua[3-ethoxy-1,8-(3,6,9-trioxaundecane-1,11-diyldioxy)-9H-xanthen-9-one]terbium(III) tris(perchlorate)
In the title compound, [Tb(CH3CN)(C23H26O8)(H2O)3](ClO4)3, the Tb3+ atom is eight-coordinated by one N atom of an acetonitrile molecule, three water O atoms and four ligand O atoms. The Tb3+ atom is located on one side of the macrocycle and the carbonyl oxygen coordinated to the terbium [Tb1—O1= 2.210 (3) Å] is bent out of the xanthone plane by 0.514 (3) Å. The geometry around terbium is a distorted two-capped trigonal prism
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