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MiRNAs play an essential role in the networks of gene regulation by inhibiting the translation of target mRNAs. Several computational approaches have been proposed for the prediction of miRNA target-genes. Reports reveal a large fraction of under-predicted or falsely predicted target genes. Thus, there is an imperative need to develop a computational method by which the target mRNAs of existing miRNAs can be correctly identified. In this study, combined pattern recognition neural network (PRNN) and principle component analysis (PCA) architecture has been proposed in order to model the complicated relationship between miRNAs and their target mRNAs in humans. The results of several types of intelligent classifiers and our proposed model were compared, showing that our algorithm outperformed them with higher sensitivity and specificity. Using the recent release of the mirBase database to find potential targets of miRNAs, this model incorporated twelve structural, thermodynamic and positional features of miRNA:mRNA binding sites to select target candidates.  相似文献   
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Current research includes the effects of asphalt forest roads on changes of plant cover and tree regeneration from asphalt forest roads edges towards its inner parts in two compartments of Nave Asalem forests located in the north of Iran. For this reason, in each side of road, 6 sample plots (20 m × 20 m) were established for measuring plant species diversity. In each sample plot, ground vegetation and tree regeneration were assessed within nine 2 × 2 m micro plots. In total, 12 sample plots and 108 μ plots were established. Results indicated that the road positions were effective on plant species diversity. The highest diversity and evenness indices value were observed down of the road compared to the up of the road position for herbal and tree regeneration layers. The same results were found also for herbal richness indices. Up of road position had the greatest value of richness indices in comparison to the other road position for tree regeneration layer. Also, the results showed that diversity, richness, and evenness indices were decreased with the increasing of distance from the road side for herbs and tree regeneration layers. This study indicated that roads can increase plant biodiversity; that is, tree regeneration density.  相似文献   
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The study presents length–weight relationships (LWRs) and length–length relationships (LLRs) for three algae‐scraper species; Capoeta coadi from the Kouhrang River (Iran; 32°23′N, 50°08′E) a part of the Tigris drainage basin, Capoeta pyragyi from Cheshmeh Langan River (32°55′N, 50°10′E) a part of Zayanderud River basin and Capoeta umbla from Chooman River (35°57′N, 45°47′E). Fish were sampled by electro fishing (Samus1000; Power Out: 200 watts) in August, September and October 2017. Sampling was carried out each months in sites covering an area of about 100 m2 including runs, riffles and pools at a water depth of 10–60 cm. The obtained LWRs and LLRs showed a high level of correlation (r> 0.99).  相似文献   
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Cancer recurrence is believed to be one of the major reasons for the failure of cancer treatment strategies. This biological phenomenon could arise from the incomplete eradication of tumour cells after chemo- and radiotherapy. Recent developments in the design of models reflecting cancer recurrence and in vivo imaging techniques have led researchers to gain a deeper and more detailed insight into the mechanisms underlying tumour relapse. Here, we provide an overview of three important drivers of recurrence including cancer stem cells (CSCs), neosis, and phoenix rising. The survival of cancer stem cells is well recognized as one of the primary causes of therapeutic resistance in malignant cells. CSCs have a relatively latent metabolism and show resistance to therapeutic agents through a variety of routes. Neosis has proven to be as an important mechanism behind tumour self-proliferation after treatment which gives rise to the expansion of tumour cells in the injured site via production of Raju cells. Phoenix rising is a pro-recurrence pathway through which apoptotic cancer cells send strong signals to the neighbouring diseased cells leading to their multiplication. The mechanisms involved in therapeutic resistance and tumour recurrence have not yet been fully understood and mostly remain unexplained. Without doubt, an improved understanding of the cellular machinery contributing to recurrence will pave the way for the development of novel, sophisticated and effective anti-tumour therapeutic strategies which can eradicate tumour without the threat of relapse.  相似文献   
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This study evaluated the ability of a hydrothermal time model (HTT) to describe the kinetics of watermelon (Citrullus vulgaris cv. ‘Crimson sweet’) seed germination under different temperatures (T) and water potentials (ψ) and also to determine the cardinal temperatures of watermelon. Results indicated that ψ influenced germination rate and germination percentage. For this seed lot, cardinal temperatures were 10 °C for T b, 28.34 °C for T o and 40.8 °C for T c in the control (0 MPa) treatment. There was a decrease in hydrotime constant (θ H) when T was increased to T o and then remained constant at supra-optimal temperatures (30 MPah?1). Also, at temperatures above T o, ψ b(50) values increased linearly with T. The k T value (the slope of the relationship between ψ b(50) and T exceeds T o) of this seed lot was calculated as 0.076 MPa°Ch?1. Results this study show that when the HTT model is applied, it can accurately describe ψ b(g) and the course of germination around Ts (R 2 = 0.82). Moreover, the ψ b(50) was estimated to be ?0.96 MPa based on this model. Consequently, the germination response of watermelon for all Ts and ψs can be adequately described by the HTT model and enabling it to be used as a predictive tool in watermelon seed germination simulation models.  相似文献   
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Biological Trace Element Research - Selenium is known to be a neuroprotective agent in respect to a number of neuronal diseases and pain. The aim of this study was to evaluate the neuroprotective...  相似文献   
130.
The anticancer activity of triamterene on HCT116 and CT26 colon cancer cells lines was investigated. Furthermore, the mechanism of interaction between triamterene and calf thymus DNA (ct-DNA) and also human serum albumin (HSA) was conducted using spectroscopic and molecular docking techniques. In vitro cytotoxicity of triamterene against HCT116 and CT26 cells showed promising anticancer effects with IC50 values of 31.30 and 24.45 μM, respectively. Competitive studies of the triamterene with NR (neutral red) and MB (methylene blue) as intercalator probes showed that triamterene can be replaced by these probes. The viscosity data also confirmed that triamterene binds to calf–thymus DNA through intercalation binding mode. Binding properties of triamterene with HSA in the presence of warfarin and ibuprofen showed that triamterene competes with warfarin for the site I of human serum albumin (HSA). In addition, the binding modes of triamterene with DNA and HSA were verified by molecular docking technique. Abbreviations ct-DNA calf thymus DNA

CV cyclic voltammetry

DNA deoxyribonucleic acid

DPV differential pulse voltammetry

FBS fetal bovine serum

HSA human serum albumin

NR neutral red

MB methylene blue

MTT 3-(4,5-dimethylthiazol-2yl)-2,5-diphenyltetrazoliumbromide

Communicated by Ramaswamy H. Sarma  相似文献   

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