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31.
Xiaoqing Wu Xiaorui Xie Linjuan Su Na Lin Bin Liang Nan Guo Qingquan Chen Liangpu Xu Hailong Huang 《Journal of cellular and molecular medicine》2021,25(18):8929-8935
Pallister-Killian syndrome (PKS) is a rare sporadic genetic disorder usually caused by mosaicism of an extra isochromosome of 12p (i(12p)). This retrospective study analysed the prenatal ultrasound manifestations and molecular and cytogenetic results of five PKS foetuses. Samples of amniotic fluid and/or cord blood, skin biopsy and placenta were collected. Conventional karyotyping and single nucleotide polymorphism array (SNP array) were performed on all the amniotic fluid or cord blood samples. Copy number variants sequencing (CNV-seq) and fluorescence in situ hybridization (FISH) were also used for the validation for one foetus. All the five foetuses were from pregnancies with advanced parental age. Two foetuses involved structural abnormalities and one foetus had only soft markers, all of which included increased nuchal translucency. The rest two foetuses had normal ultrasounds in the second trimester, which has rarely been reported before. The karyotype revealed typical i(12p) in four cases and a small supernumerary marker chromosome consisting of 12p and 20p in the remaining one case. The proportion of cells with i(12p) ranged from 0 to 100% in cultural cells, while SNP array results suggested 2−4 copies of 12p. For one foetus, metaphase FISH showed normal results, but the interphase FISH suggested cell lines with two, three and four copies of 12p in the amniotic fluid. Advanced parental age may be an important risk factor for PKS, and there were no typical ultrasound manifestations related to PKS. A combination of karyotype analysis and molecular diagnosis is an effective method for the diagnosis of PKS. 相似文献
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Photosynthesis-irradiance (PI) curves are extensively used in field and laboratory research to evaluate the photon-use efficiency of plants. However, most existing models for PI curves focus on the relationship between the photosynthetic rate (Pn) and photosynthetically active radiation (PAR), and do not take account of the influence of environmental factors on the curve. In the present study, we used a new non-competitive inhibited Michaelis-Menten model (NIMM) to predict the co-variation of Pn, PAR, and the relative pollution index (I). We then evaluated the model with published data and our own experimental data. The results indicate that the Pn of plants decreased with increasing I in the environment and, as predicted, were all fitted well by the NIMM model. Therefore, our model provides a robust basis to evaluate and understand the influence of environmental pollution on plant photosynthesis. 相似文献
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Xian-Hui Dong Dong-Xue Ma Tian-Ci Zhang Xiao-Ping He Li-Jun Xu Ya-Lei Liu Hao Li Wei-Juan Gao 《Neurochemical research》2021,46(5):1068-1080
Neurochemical Research - Alzheimer’s disease (AD) process is characterized classically by two hallmark pathologies: β-amyloid (Aβ) plaque deposition and neurofibrillary tangles of... 相似文献
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Plasmonics - We investigate aluminum nanopatch/nanohole arrays surrounded by a dielectric material on plastic substrates for large area color printing. In this specific arrangement, metallic... 相似文献
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Genome‐wide detection of CNVs associated with beak deformity in chickens using high‐density 600K SNP arrays 下载免费PDF全文
H. Bai Y. Sun N. Liu Y. Liu F. Xue Y. Li S. Xu A. Ni J. Ye Y. Chen J. Chen 《Animal genetics》2018,49(3):226-236
Beak deformity (crossed beaks) is found in several indigenous chicken breeds including Beijing‐You studied here. Birds with deformed beaks have reduced feed intake and poor production performance. Recently, copy number variation (CNV) has been examined in many species and is recognized as a source of genetic variation, especially for disease phenotypes. In this study, to unravel the genetic mechanisms underlying beak deformity, we performed genome‐wide CNV detection using Affymetrix chicken high‐density 600K data on 48 deformed‐beak and 48 normal birds using penncnv . As a result, two and eight CNV regions (CNVRs) covering 0.32 and 2.45 Mb respectively on autosomes were identified in deformed‐beak and normal birds respectively. Further RT‐qPCR studies validated nine of the 10 CNVRs. The ratios of six CNVRs were significantly different between deformed‐beak and normal birds (P < 0.01). Within these six regions, three and 21 known genes were identified in deformed‐beak and normal birds respectively. Bioinformatics analysis showed that these genes were enriched in six GO terms and one KEGG pathway. Five candidate genes in the CNVRs were further validated using RT‐qPCR. The expression of LRIG2 (leucine rich repeats and immunoglobulin like domains 2) was lower in birds with deformed beaks (P < 0.01). Therefore, the LRIG2 gene could be considered a key factor in view of its known functions and its potential roles in beak deformity. Overall, our results will be helpful for future investigations of the genomic structural variations underlying beak deformity in chickens. 相似文献
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This paper studies a Non-convex State-dependent Linear Quadratic Regulator (NSLQR) problem, in which the control penalty weighting matrix in the performance index is state-dependent. A necessary and sufficient condition for the optimal solution is established with a rigorous proof by Euler-Lagrange Equation. It is found that the optimal solution of the NSLQR problem can be obtained by solving a Pseudo-Differential-Riccati-Equation (PDRE) simultaneously with the closed-loop system equation. A Comparison Theorem for the PDRE is given to facilitate solution methods for the PDRE. A linear time-variant system is employed as an example in simulation to verify the proposed optimal solution. As a non-trivial application, a goal pursuit process in psychology is modeled as a NSLQR problem and two typical goal pursuit behaviors found in human and animals are reproduced using different control weighting . It is found that these two behaviors save control energy and cause less stress over Conventional Control Behavior typified by the LQR control with a constant control weighting , in situations where only the goal discrepancy at the terminal time is of concern, such as in Marathon races and target hitting missions. 相似文献