BACKGROUND: The purpose of this study was to evaluate whether the chest radiograph is a reliable tool to assess response to radiotherapy. MATERIALS AND METHODS: Pre- and post-treatment chest radiographs and computed tomographs (CT) of 63 patients with nonsmall cell lung cancer (NSCLC) treated by radiotherapy were reviewed by four observers with regard to suitability for tumor measurement, and response. Suitability for tumor measurement was expressed as the number of measurable diameters. In addition, the consequences to clinical outcome were studied by survival analysis. RESULTS: The CT turned out to be more suited for tumor measurement before as well as after radiotherapy, resulting in an increase of the number of measurable cases. The number of measurable cases with CT was 52 (83%) as compared to 28 (44%) with chest radiography. Especially in case of centrally localized tumors, the presence of an atelectasis, or squamous cell carcinoma, CT contributed to a higher rate of measurable cases. The interobserver agreement with regard to response using chest radiograph was good (mean kappa = 0.74). In 25 of 28 cases (89%) measurable with CT as well as with chest radiograph, response was equally classified. When CT was used, the median survival of the responders was 14.2 months as compared to 6.8 months of the nonresponders. When chest radiograph was used, the median survival of these groups was 12.0 and 6.6 months respectively, which was not significantly different when response was assessed by CT. CONCLUSION: We conclude that CT is more suited for tumor measurement because more measurable lesions can be found and more evaluable lesions on chest radiograph become measurable on CT. The chest radiograph does have a valuable role to play in those lesions that are measurable because of the good interobserver agreement with regard to the response classification, the high overall agreement between CT and chest radiograph in case of measurable cases, and the lack of important differences with regard to survival. 相似文献
The question answer (QA) system for a reading comprehension task tries to answer the question by retrieving the needed phrase from the given content. Precise answering is the key role of a QA system. An ambiguity is developed when we need to answer a negative question with a positive reply. The negation words change the polarity of the sentence, and hence, the scope of negation words is notable.
This has paved the way for studying the role of ‘negation’ in the natural language processing (NLP) task. The handling of these words is considered a major part of our proposed methodology. In this paper, we propose an algorithm to retrieve and replace the negation words present in the content and query. A comparative study is done for performing word embedding over these words using various state-of-the-art methods. In earlier works when handling the negation the semantics of the sentences are changed. Hence, in this paper we try to maintain the semantics through our proposed methodology. The updated content is embedded into the bi-directional long short-term memory (Bi-LSTM) and thus makes the retrieving of an answer for a question answer system easier. The proposed work has been carried over the Stanford Negation, and the SQuAD dataset with a higher precision value of 96.2% has been achieved in retrieving the answers that are given in the dataset.
For some years now, the Nederlandse Taalunie (Dutch Language Union) has been active in promoting the development of human
language technology (HLT) applications for speakers of Dutch with communicative disabilities. The reason is that HLT products
and services may enable them to improve their communication skills and verbal autonomy. We sought to identify a minimum common
set of HLT resources that is required to develop tools for a wide range of communication disabilities. In order to reach this
goal, we investigated the specific needs of communicatively disabled people and related these needs to the underlying HLT
software components. By analysing the availability and quality of these essential HLT resources, we were able to identify
which of the crucial elements need further research and development to become usable for developing applications for communicatively
disabled speakers of Dutch. The results obtained in the current survey can be used to inform policy institutions on how they
can stimulate the development of HLT resources for this target group. In the current survey results were obtained for Dutch,
but a similar approach can also be applied to other languages. 相似文献
A novel poly(p-xylylene), PPX, derivative bearing alkoxyphenyl side groups was electrochemically synthesized in 87% yield. The polymer, poly(4′-hexyloxy-2,5-biphenyleneethylene) (PHBPE), presented a fraction (92%) soluble in common organic solvents. It showed to be thermally resistant up to 185 °C. UV–vis analysis revealed an Egap of 3.5 eV. Gas sensors made from thin films of 10-camphorsulfonic acid-doped PHBPE deposited on interdigitated electrodes exhibited significant changes in electrical conductance upon exposure to five VHOCs: 1,2-dichloroethane, bromochloromethane, trichloromethane, dichloromethane and tetrachloromethane. The conductance decreased after exposure to tetrachloromethane and increased after exposure to all the other VHOCs. Three-dimensional plots of relative response versus time of half response versus time of half recovery showed good discrimination between the five VHOCs tested. 相似文献
The recognition of digital shapes is a deeply studied problem. The arithmetical framework, initiated by Reveillès [Géométrie discrète, calcul en nombres entiers et algorithmique, Thèse d’Etat, 1991], provides a powerful theoretical basis, as well as many algorithms to deal with digital objects. The tangential cover, first presented in Feschet and Tougne [Optimal time computation of the tangent of a discrete curve: application to the curvature, in: G. Bertrand, M. Couprie, L. Perroton (Eds.), 8th Discrete Geometry for Computer Imagery, Lecture Notes in Computer Science, vol. 1568, Springer, Berlin, 1999, pp. 31-40] and Feschet [Canonical representations of discrete curves, Pattern Anal. Appl. 8(1-2) (2005) 84-94] is a useful tool for representing geometric digital primitives. It computes the set of all maximal segments of a digital curve and permits either to obtain minimal length polygonalization or asymptotic convergence of tangents estimations. Nevertheless, the arithmetical approach does not tolerate the introduction of irregularities, which are however inherent to the acquisition of digital shapes. The present paper is an extension of Faure and Feschet [Tangential cover for thick digital curves, in: D. Coeurjolly, I. Sivignon, L. Tougne, F. Dupont (Eds.), DGCI 2008, Lecture Notes in Computer Science, vol. 4992, Springer, Berlin, 2008, pp. 358-369], in which we propose a new definition for a class of the so-called “thick digital curves” that applies well to a large class of digital object boundaries. We then propose an extension of the tangential cover to thick digital curves and provide an algorithm with an O(nlogn) time complexity, where n denotes the number of points of specific subparts of the thick digital curve. In order to keep up with this low complexity, some critical points must be taken into account. We describe all required implementation details in this paper. 相似文献
Variants in genes encoding for microRNAs have been associated with their deregulation in breast cancer (BC). Sequencing of microRNAs deregulated in BC was performed using DNA from Chilean patients with a strong family history and negative for mutations in BRCA1/BRCA2. Seventeen variants were identified, three of which were selected for a case-control association study: rs376491654 (miR-335), rs755634302 (miR-497), and rs190708267 (miR-155). For rs190708267 C>T, the heterozygous T allele was detected in four BC cases and absent in controls, while homozygous TT cases were not detected. Variants were modelled in silico, cloned in a plasmid, expressed in BC cell lines, and functional in vitro assays were performed. Overexpression of the miR-155-T allele increased mature miR-155-5p levels in both BC cell lines, suggesting that its presence alters pre-miR-155 processing. Moreover, BC cells overexpressing the miR-155-T allele showed increased proliferation, migration, and resistance to cisplatin-induced death compared to miR-155-C overexpressing cells. Of note, the 3′UTR of APC, GSK3β, and PPP1CA genes, all into the canonical Wnt signaling pathway, were identified as direct targets. APC and GSK3β mRNA levels decreased while PP1 levels increased. These results suggest a pathogenic role of the variant rs190708267 (miR-155) in BRCA 1/2 negative BC, conferring susceptibility and promoting traits of aggressiveness. 相似文献
p27kip1 is a multifunctional protein that promotes cell cycle exit by blocking the activity of cyclin/cyclin-dependent kinase complexes as well as migration and motility via signaling pathways that converge on the actin and microtubule cytoskeleton. Despite the broad characterization of p27kip1 function in neural cells, little is known about its relevance in microglia. Here, we studied the role of p27kip1 in microglia using a combination of in vitro and in situ approaches. While the loss of p27kip1 did not affect microglial density in the cerebral cortex, it altered their morphological complexity in situ. However, despite the presence of p27kip1 in microglial processes, as shown by immunofluorescence in cultured cells, loss of p27kip1 did not change microglial process motility and extension after applying laser-induced brain damage in cortical brain slices. Primary microglia lacking p27kip1 showed increased phagocytic uptake of synaptosomes, while a cell cycle dead variant negatively affected phagocytosis. These findings indicate that p27kip1 plays specific roles in microglia. 相似文献
Tumor necrosis factor (TNF)-α is a pleiotropic cytokine implicated in the etiology of several autoimmune diseases, including rheumatoid arthritis (RA). TNF-α regulates diverse effector functions through the activation of TNF-α receptor (TNFR)1 and TNFR2. Although the detrimental role of this cytokine has been addressed in distinct disease settings, the effects of TNF-α on cytokine production by isolated CD4+ T helper type 1 (Th1) and Th17 cells, two T cell subpopulations that contribute to the pathogenesis of RA, have not been completely elucidated. Here, we show that TNF-α promotes a reduction and expansion in the frequency of both T cell subsets producing IFN-γ and IL-17, respectively. Selective blockade of TNFR1 or TNFR2 on Th1 and Th17 cells revealed that TNFR2 mediates the decrease in IFN-γ production, while signaling through both receptors augments IL-17 production. We also demonstrate that Th1, but not Th17 cells from RA patients present lower levels of TNFR1 compared to healthy controls, whereas TNFR2 expression on both T cell types is similar between patients and controls. Since TNF-α receptors levels in RA patients are not significantly changed by the therapeutic blockade of TNF-α, we propose that targeting TNFR2 may represent an alternative strategy to normalize the levels of key cytokines that contribute to RA pathogenesis. 相似文献