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Autism spectrum disorder:difficulties in diagnosis and microRNA biomarkers
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作者 Bridget Martinez Philip V.Peplow 《Neural Regeneration Research》 SCIE CAS 2025年第10期2776-2786,共11页
We performed a PubMed search for microRNAs in autism spectrum disorder that could serve as diagnostic biomarkers in patients and selected 17 articles published from January 2008 to December 2023,of which 4 studies wer... We performed a PubMed search for microRNAs in autism spectrum disorder that could serve as diagnostic biomarkers in patients and selected 17 articles published from January 2008 to December 2023,of which 4 studies were performed with whole blood,4 with blood plasma,5 with blood serum,1 with serum neural cell adhesion molecule L1-captured extracellular vesicles,1 with blood cells,and 2 with peripheral blood mononuclear cells.Most of the studies involved children and the study cohorts were largely males.Many of the studies had performed microRNA sequencing or quantitative polymerase chain reaction assays to measure microRNA expression.Only five studies had used real-time polymerase chain reaction assay to validate microRNA expression in autism spectrum disorder subjects compared to controls.The microRNAs that were validated in these studies may be considered as potential candidate biomarkers for autism spectrum disorder and include miR-500a-5p,-197-5p,-424-5p,-664a-3p,-365a-3p,-619-5p,-664a-3p,-3135a,-328-3p,and-500a-5p in blood plasma and miR-151a-3p,-181b-5p,-320a,-328,-433,-489,-572,-663a,-101-3p,-106b-5p,-19b-3p,-195-5p,and-130a-3p in blood serum of children,and miR-15b-5p and-6126 in whole blood of adults.Several important limitations were identified in the studies reviewed,and need to be taken into account in future studies.Further studies are warranted with children and adults having different levels of autism spectrum disorder severity and consideration should be given to using animal models of autism spectrum disorder to investigate the effects of suppressing or overexpressing specific microRNAs as a novel therapy. 展开更多
关键词 autism spectrum disorder BIOMARKER blood cells blood plasma blood serum DIAGNOSIS MICRORNA peripheral blood mononuclear cells serum neural cell adhesion molecule L1-captured extracellular vesicles whole blood
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On The Hardening of The Spectrum of High-Energy Particles Formed in Heavy-Ion Collisions Considered within The Framework of The Hydrodynamic Approach
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作者 Alexander T. D’ yachenko Konstantin A. Gridnev 《Journal of Modern Physics》 2011年第1期8-11,共4页
The emission of high-energy particles in 16O + 197Au collisions at energy 20 MeV / nucleon is considered within the framework of the time evolution of a hot spot taking into account the hydrodynamic compression and ex... The emission of high-energy particles in 16O + 197Au collisions at energy 20 MeV / nucleon is considered within the framework of the time evolution of a hot spot taking into account the hydrodynamic compression and expansion stages. In addition, the evaporation of the particles that are formed in the early (hot) stage of the evolution of the hot spot is included in the calculation of the spectrum. This leads to a hardening of the particle spectrum in its high-energy part, which is in agreement with experimental data. 展开更多
关键词 HARDENING of The spectrum High-Energy Particles HEAVY-ION Hydrodynamics Hot Spot FERMI-LIQUID FREEZE-OUT Density Skyrme-Type Interaction Double Differential Cross-Section Time Evolution Evaporation
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Dynamic Promotional Resource Allocation for Segment Specific and Spectrum Effect of Promotion for a Product Line Incorporating Repeat Purchase Behavior 被引量:1
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作者 Prakash Chandra Jha Prerna Manik Anshu Gupta 《American Journal of Operations Research》 2013年第3期350-362,共13页
Promotion is an essential element in the marketing mix. It is used by businesses to inform, influence and persuade customers to adopt the products and services they offer. Without promotion, business would be stagnant... Promotion is an essential element in the marketing mix. It is used by businesses to inform, influence and persuade customers to adopt the products and services they offer. Without promotion, business would be stagnant and lack substantial growth because the brands would have low visibility in the market. Moreover, today’s vast and assorted markets comprise of customers with different needs and varied behavior. So it is rarely possible for companies to satisfy all customers by treating them alike. Thus there arises a need to divide the market into segments having customers with similar traits/characteristics. After identifying appropriate market segments, firms can design differentiated promotional campaigns for each segment. At the same time there can be a mass market promotional campaign that reaches different segments with a fixed spectrum. Also since promotional effort resources are limited, one must use them judiciously. In this paper, we formulate mathematical programming problem under repeat purchase scenario, which optimally allocates mass promotional effort resources and differentiated promotional effort resources across the segments dynamically in order to maximize the overall sales obtained from multiple products of a product line under budgetary and minimum sales aspiration level constraint on each product under consideration in each segment. The planning horizon is divided into multi periods, the adoption pattern of each product in each segment is observed in every subinterval and accordingly promotional effort allocations are determined for the next period till we reach the end of planning period. The optimization model has been further extended to incorporate minimum aspiration level constraints on total sales for each product under consideration from all the segments taken together. The non linear programming problem so formulated is solved using differential evolution approach. A numerical example has been discussed to illustrate applicability of the model. 展开更多
关键词 MARKET Segmentation DIFFERENTIATED MARKET PROMOTION Mass MARKET PROMOTION spectrum EFFECT Promotional Effort Allocation REPEAT Purchase Product Line Non Linear Programming Problem Differential Evolution
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Frequency Hopping Spread Spectrum Security Improvement with Encrypted Spreading Codes in a Partial Band Noise Jamming Environment 被引量:1
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作者 Amirhossein Ebrahimzadeh Abolfazl Falahati 《Journal of Information Security》 2013年第1期1-6,共6页
Frequency Hopping Spread Spectrum (FHSS) system is often deployed to protect wireless communication from jamming or to preclude undesired reception of the signal. Such themes can only be achieved if the jammer or unde... Frequency Hopping Spread Spectrum (FHSS) system is often deployed to protect wireless communication from jamming or to preclude undesired reception of the signal. Such themes can only be achieved if the jammer or undesired receiver does not have the knowledge of the spreading code. For this reason, unencrypted M-sequences are a deficient choice for the spreading code when a high level of security is required. The primary objective of this paper is to analyze vulnerability of linear feedback shift register (LFSRs) codes. Then, a new method based on encryption algorithm applied over spreading codes, named hidden frequency hopping is proposed to improve the security of FHSS. The proposed encryption security algorithm is highly reliable, and can be applied to all existing data communication systems based on spread spectrum techniques. Since the multi-user detection is an inherent characteristic for FHSS, the multi-user interference must be studied carefully. Hence, a new method called optimum pair “key-input” selection is proposed which reduces interference below the desired constant threshold. 展开更多
关键词 FREQUENCY HOPPING SPREAD spectrum KEY Distribution Centre KEY Encryption KEY Linear Feedback Shift REGISTER FREQUENCY HOPPING Code Division Multiple Access Direct Sequence SPREAD spectrum
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Association of GTF2IRD1–GTF2I polymorphisms with neuromyelitis optica spectrum disorders in Han Chinese patients 被引量:4
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作者 Jing-Lu Xie Ju Liu +7 位作者 Zhi-Yun Lian Hong-Xi Chen Zi-Yan Shi Qin Zhang Hui-Ru Feng Qin Du Xiao-Hui Miao Hong-Yu Zhou 《Neural Regeneration Research》 SCIE CAS CSCD 2019年第2期346-353,共8页
Variants at the GTF2I repeat domain containing 1(GTF2IRD1)–GTF2I locus are associated with primary Sj?gren's syndrome, systemic lupus erythematosus, and rheumatoid arthritis. Numerous studies have indicated that ... Variants at the GTF2I repeat domain containing 1(GTF2IRD1)–GTF2I locus are associated with primary Sj?gren's syndrome, systemic lupus erythematosus, and rheumatoid arthritis. Numerous studies have indicated that this susceptibility locus is shared by multiple autoimmune diseases. However, until now there were no studies of the correlation between GTF2IRD1–GTF2I polymorphisms and neuromyelitis optica spectrum disorders(NMOSD). This case control study assessed this association by recruiting 305 participants with neuromyelitis optica spectrum disorders and 487 healthy controls at the Department of Neurology, from September 2014 to April 2017. Peripheral blood was collected, DNA extracteds and the genetic association between GTF2IRD1–GTF2I polymorphisms and neuromyelitis optica spectrum disorders in the Chinese Han population was analyzed by genotyping. We found that the T allele of rs117026326 was associated with an increased risk of neuromyelitis optica spectrum disorders(odds ratio(OR) = 1.364, 95% confidence interval(CI) 1.019–1.828; P = 0.037). This association persisted after stratification analysis for aquaporin-4 immunoglobulin G antibodies(AQP4-IgG) positivity(OR = 1.397, 95% CI 1.021–1.912; P = 0.036) and stratification according to coexisting autoimmune diseases(OR = 1.446, 95% CI 1.072–1.952; P = 0.015). Furthermore, the CC genotype of rs73366469 was frequent in AQP4-IgG-seropositive patients(OR = 3.15, 95% CI 1.183–8.393, P = 0.022). In conclusion, the T allele of rs117026326 was associated with susceptibility to neuromyelitis optica spectrum disorders, and the CC genotype of rs73366469 conferred susceptibility to AQP4-IgG-seropositivity in Han Chinese patients. The protocol was approved by the Ethics Committee of West China Hospital of Sichuan University, China(approval number: 2016-31) on March 2, 2016. 展开更多
关键词 nerve REGENERATION neuromyelitis optica spectrum DISORDERS GTF2I GTF2IRD1 single-nucleotide polymorphism AUTOIMMUNE diseases AQUAPORIN-4 linkage disequilibrium HAPLOTYPE neural REGENERATION
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极区中层顶区域重力波谱的季节变化
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作者 吴永富 徐寄遥 《空间科学学报》 CAS CSCD 北大核心 2005年第3期191-198,共8页
使用MAP/WINE和MAC/SINE两次试验中测量的25m高分辨率水平速度数据和1km低分辨率温度数据,研究极区中层顶区域重力波谱的季节变化.温度的直接测量使计算的谱振幅和Richardson数更接近真实大气.结果显示,极区中层顶区域水平速度垂直波数... 使用MAP/WINE和MAC/SINE两次试验中测量的25m高分辨率水平速度数据和1km低分辨率温度数据,研究极区中层顶区域重力波谱的季节变化.温度的直接测量使计算的谱振幅和Richardson数更接近真实大气.结果显示,极区中层顶区域水平速度垂直波数谱的斜率和振幅存在相当大的变率,这些大的观测变率用各种饱和模式及普适垂直波数谱不能解释.然而平均垂直波数谱显示了明显的季节变化,在夏季,平均谱具有饱和特性;在冬季,平均谱具有非饱和特性.这意味着饱和过程存在于夏季而不是冬季.因此,夏季比冬季应有更强的湍流.这个结果与湍流季节变化的观测大致一致.从Brunt-Vaisala频率N和水平风切变计算的Richardson数Ri剖面也显示出季节差异,Ri<1/4的动力不稳定区出现在夏季,而Ri>0.4的稳定区出现在冬季.这些不稳定区与夏季谱结合很好,而稳定区则与冬季谱结合很好. 展开更多
关键词 Richardson WINE MAC MAP
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A Dynamic Distributed Spectrum Allocation Mechanism Based on Game Model in Fog Radio Access Networks 被引量:2
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作者 Yao Yu Shumei Liu +1 位作者 Zhongshi Tian Siyu Wang 《China Communications》 SCIE CSCD 2019年第3期12-21,共10页
With the explosive growth of highspeed wireless data demand and the number of mobile devices, fog radio access networks(F-RAN) with multi-layer network structure becomes a hot topic in recent research. Meanwhile, due ... With the explosive growth of highspeed wireless data demand and the number of mobile devices, fog radio access networks(F-RAN) with multi-layer network structure becomes a hot topic in recent research. Meanwhile, due to the rapid growth of mobile communication traffic, high cost and the scarcity of wireless resources, it is especially important to develop an efficient radio resource management mechanism. In this paper, we focus on the shortcomings of resource waste, and we consider the actual situation of base station dynamic coverage and user requirements. We propose a spectrum pricing and allocation scheme based on Stackelberg game model under F-RAN framework, realizing the allocation of resource on demand. This scheme studies the double game between the users and the operators, as well as between the traditional operators and the virtual operators, maximizing the profits of the operators. At the same time, spectrum reuse technology is adopted to improve the utilization of network resource. By analyzing the simulation results, it is verified that our proposed scheme can not only avoid resource waste, but also effectively improve the operator's revenue efficiency and overall network resource utilization. 展开更多
关键词 FOG radio access networks(F-RAN) game theory spectrum REUSE technology base station DYNAMIC COVERAGE spectrum PRICING and allocation
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二正丁基二硫代氨基甲酸锌配合物的量子化学研究 被引量:9
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作者 许旋 方亮 +3 位作者 徐志广 陈兆星 钟昀 章伟光 《无机化学学报》 SCIE CAS CSCD 北大核心 2005年第7期1049-1054,共6页
The geometric configurations of binuclear Zinc( complex Zn2[(n-Bu)2NCSS]4 and the ligand Na[(n-Bu)2 NCSS] have been optimized by B3LYP quantum chemical method. The electronic structures have been performed by density ... The geometric configurations of binuclear Zinc( complex Zn2[(n-Bu)2NCSS]4 and the ligand Na[(n-Bu)2 NCSS] have been optimized by B3LYP quantum chemical method. The electronic structures have been performed by density functional theory at B3LYP/6-31G* level. The electronic spectrums of the complex and ligand were calculated by ZINDO/S-CIS method. It is indicated from the calculation that: (1) The coordination effect of bridging ligand is bigger than that of chelating one, and the bridging ligands also translate more charge to Zn than the chelating one. (2) The calculated results about electronic spectrums are similarly to experimental measurement, and farther explain that absorption band at λ=267 nm of complex is assigned to two n → π* transitions :one arising from the bridging ligands and the another mainly arising from the chelating ligands;but absorption band at λ=236 nm of complex is assigned to π → π* transition which the electron mainly translates from the bridging ligands to the chelating ligands. (3) By consideration of delocalization and polar effects in coordination, the charge transfer from ligand to metal decreases the π-π and p-π conjugation effects in the chromophore group NCS2 and to increase the energy needed for the π → π* and n → π* transitions, and results in the absorption bands shifting towards the short wavelength direction. 展开更多
关键词 experimental complex effects quantum direct the and The B3LYP polar metal group Zinc more LIGA to is at one are for π
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Cognitive inflexibility in Japanese adolescents and adults with autism spectrum disorders 被引量:1
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作者 Yuka Yasuda Ryota Hashimoto +5 位作者 Kazutaka Ohi Hidenaga Yamamori Michiko Fujimoto Satomi Umeda-Yano Haruo Fujino Masatoshi Takeda 《World Journal of Psychiatry》 SCIE 2014年第2期42-48,共7页
AIM: To investigate executive function in Japanese adolescents and adults with autism spectrum disorders(ASD) compared to Japanese controls.METHODS: Thirty-three individuals with ASD and 33 controls participated. The ... AIM: To investigate executive function in Japanese adolescents and adults with autism spectrum disorders(ASD) compared to Japanese controls.METHODS: Thirty-three individuals with ASD and 33 controls participated. The ASD and control groups' demographic variables were matched for gender(male/female: 20/13 vs 20/13), age(26.1 ± 11.5 vs 26.8 ± 9.6), years of education(13.2 ± 2.9 vs 14.2 ± 1.9), full-scale intelligence quotient(IQ)(103.0 ± 16.7 vs 103.7 ± 14.7), performance IQ(96.2 ± 16.1 vs 97.8 ± 15.0), and verbal IQ(107.9 ± 16.3 vs 107.7 ± 14.4). Participants performed the Wisconsin Card Sorting Test(WCST), which assesses the executive processes involved in problem solving and cognitive flexibility, and the Continuous Performance Test(CPT), which assesses attention and impulsivity. Symptoms were assessed by the Autism-Spectrum Quotient Japanese version(AQ-J). First, we compared the scores of the WCST between the groups using a Mann-Whitney U-test and conducted an analysis of covariance for the variables with the scores of category archives and CPT scores as covariates. Second, we analyzed the correlation between the scores of the WCST and the AQ-J in the ASD group using Pearson's r.RESULTS: The total errors(TE) and the percentages of perseverative errors of the Milner type(%PEM) and Nelson type(%PEN) among the TE in the ASD group were significantly worse compared with the control group(ASD vs Control, respectively: TE: 16.0 ± 6.2 vs 12.6 ± 3.5, P = 0.012; %PEM: 11.7 ± 10.7 vs 6.6 ± 8.9, P = 0.037; %PEN: 20.1 ± 14.5 vs 8.7 ± 10.4, P = 0.0011). In contrast, no significant difference was observed between the two groups in the scores of categories achieved on the WCST or the CPT. An analysis of covariance revealed significant differences between the groups in the %PEN scores(P = 0.0062) but not in the TE or the %PEM scores. These results suggest that Japanese adolescents and adults with ASD have cognitive inflexibility. Furthermore, our results suggest that Japanese adolescents and adults with ASD may have difficulties using negative feedback because perseverative errors of the Nelson type indicate persistence in choosing the incorrect reaction. By contrast, there was no significant correlation between the WCST and AQ-J scores.CONCLUSION: We confirmed the presence of cognitive inflexibility in Japanese adolescents and adults with ASD. Our results also indicated that subjects with ASD may not use negative feedback effectively. 展开更多
关键词 EXECUTIVE function AUTISM spectrum DISORDERS Perseverative errors of NELSON type Negative feedback WISCONSIN Card Sorting Test
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Molecular Features of Highly Pathogenic Avian and Human H5N1 Influenza A Viruses in Asia
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作者 Wei Hu 《Computational Molecular Bioscience》 2012年第2期45-59,共15页
The highly pathogenic avian H5N1 influenza virus could infect humans with high mortality rate, even though it has not yet become efficiently transmissible among humans. This proteomic study investigated the molecular ... The highly pathogenic avian H5N1 influenza virus could infect humans with high mortality rate, even though it has not yet become efficiently transmissible among humans. This proteomic study investigated the molecular basis of interspecies transmission and host range of this lethal virus in Asia, due to its potential pandemic threat. Although there are host markers located in previous research between general avian and human influenza viruses, the novelty of our work was to uncover host markers between highly pathogenic avian and human H5N1 viruses in Asia. Many host markers we found were not present in the previous general markers, thus expanding the current repertoire of host markers with these strain-specific host markers. Ranked by their order of importance, the top 10 host markers discovered in this report were PB2_627, HA_325, NS1_205, PB2_524, HA_86, NA_201, NP_373, NS1_7, HA_156, NA_74, confirming our current knowledge that PB2_627 is the most critical site for distinguishing avian and human H5N1. We also identified several naturally-occurred mutations in the HA protein that might shift the receptor binding preference of Asian avian H5N1, since early detection of mutations that might lead to emergence of a new pandemic virus is of prime importance. Finally, we analyzed the distinctive interaction patterns within and between proteins of avian and human H5N1 in Asia at protein level and individual residue level. From multiple viewpoints, our findings reinforced the experimental observation that multiple genes of Asian avian H5N1 are involved in its gradual adaptation to human hosts. 展开更多
关键词 Entropy H5N1 HEMAGGLUTININ HOST Marker INFLUENZA Informational spectrum Method Mutation Mutual Information Random Forest Receptor Binding SPECIFICITY
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超声波对胰蛋白酶水解酪蛋白的影响 被引量:32
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作者 朱少娟 施用晖 乐国伟 《食品与生物技术学报》 CAS CSCD 北大核心 2005年第2期50-54,共5页
研究了超声场下胰蛋白酶水解酪蛋白的酶解反应条件与动力学.在超声波频率 20 kHz、作用与间歇时间比为1∶1时,测定了不同功率下胰蛋白酶活性及该酶的最适温度、最适 pH和米氏常数Km 的影响.结果表明,180,225 W功率下,超声10 min的酪蛋... 研究了超声场下胰蛋白酶水解酪蛋白的酶解反应条件与动力学.在超声波频率 20 kHz、作用与间歇时间比为1∶1时,测定了不同功率下胰蛋白酶活性及该酶的最适温度、最适 pH和米氏常数Km 的影响.结果表明,180,225 W功率下,超声10 min的酪蛋白水解率显著高于常规对照组(P<0.05); 225 W超声功率下,在5 ℃,10 ℃,20 ℃下水解率分别比对照组提高 4.4 倍、2.47倍和2.33倍(P<0.01);超声场下胰蛋白酶 Km 值减小,Vm 增大.将胰蛋白酶、底物分别进行超声处理,紫外和荧光光谱分析观察到,超声处理后,酶溶液荧光发射光波长从334 nm移至332 nm,荧光强度提高,表明一定的超声波可能使酶及底物分子构象发生变化,提高胰蛋白酶水解活性. 展开更多
关键词 pH 20 KM
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流域年径流时间序列的奇异谱分析 被引量:7
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作者 李亚伟 詹卫华 +1 位作者 卫东山 董青 《水电能源科学》 北大核心 2010年第10期19-22,共4页
将奇异谱分析(SSA)法应用于新疆维吾尔自治区伊犁河雅马渡站年径流预报,分析了流域多年径流时间序列奇异谱,提取年径流序列的时间主成分量,重构了原序列中的周期震荡成分,获得了径流时间序列规律,并采用时间序列分析中的AR(p)自回归模... 将奇异谱分析(SSA)法应用于新疆维吾尔自治区伊犁河雅马渡站年径流预报,分析了流域多年径流时间序列奇异谱,提取年径流序列的时间主成分量,重构了原序列中的周期震荡成分,获得了径流时间序列规律,并采用时间序列分析中的AR(p)自回归模型预测了流域年径流序列。实例结果表明,SSA法具有较好的实用性,为深入研究流域径流规律提供了依据。 展开更多
关键词 Time Series Annual RUNOFF Singular spectrum Analysis SSA
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Post-appendectomy pelvic abscess with extended-spectrum beta-lactamase producing Escherichia coli : A case report and review of literature 被引量:1
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作者 Andrew Tse Rajkumar Cheluvappa Selwyn Selvendran 《World Journal of Clinical Cases》 SCIE 2018年第16期1175-1181,共7页
BACKGROUND Appendicitis, the inflammation of the appendix, is the most common abdominal surgical emergency requiring expedient surgical intervention. Extendedspectrum beta-lactamases(ESBLs) are bacterial enzymes that ... BACKGROUND Appendicitis, the inflammation of the appendix, is the most common abdominal surgical emergency requiring expedient surgical intervention. Extendedspectrum beta-lactamases(ESBLs) are bacterial enzymes that catalyse the degradation of the betalactam ring of penicillins and cephalosporins(but without carbapenemase activity), leading to resistance of these bacteria to beta-lactam antibiotics. Recent increases in incidence of ESBL-producing bacteria have caused alarm worldwide. Proportion estimates of ESBLEnterobacteriaceae hover around 46% in China, 42% in East Africa, 12% in Germany, and 8% in the United States.CASE SUMMARY The impact of ESBL-producing bacteria on appendiceal abscesses and consequent pelvic abscesses are yet to be examined in depth. A literature review using the search words "appendiceal abscesses" and "ESBL Escherichia coli(E. coli)" revealed very few cases involving ESBL E. coli in any capacity in the context of appendiceal abscesses. This report describes the clinical aspects of a patient with appendicitis whodeveloped a postoperative pelvic abscess infected with ESBL-producing E. coli. In this report, we discuss the risk factors for contracting ESBL E. coli infection in appendicitis and post-appendectomy pelvis abscesses. We also discuss our management approach for postappendectomy ESBL E. coli pelvic abscesses, including drainage, pathogen identification, and pathogen characterisation. When ESBL E. coli is confirmed, carbapenem antibiotics should be promptly administered, as was done efficaciously with this patient. Our report is the first one in a developed country involving ESBL E. coli related surgical complications in association with a routine laparoscopic appendectomy.CONCLUSION Our report is the first involving ESBL E. coli and appendiceal abscesses, and that too consequent to laparoscopic appendectomy. 展开更多
关键词 APPENDECTOMY APPENDICEAL ABSCESS Appendicitis BETA-LACTAM Antibiotic resistance BETA-LACTAMASE Carbanepem CEPHALOSPORIN Escherichia coli Extended-spectrum BETA-LACTAMASE Infection Pelvic ABSCESS Penicillin Case report
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Rational use of mesenchymal stem cells in the treatment of autism spectrum disorders 被引量:6
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作者 Qiang Liu Mo-Xian Chen +5 位作者 Lin Sun Chloe U Wallis Jian-Song Zhou Li-Juan Ao Qi Li Pak C Sham 《World Journal of Stem Cells》 SCIE CAS 2019年第2期55-72,共18页
Autism and autism spectrum disorders(ASD) refer to a range of conditions characterized by impaired social and communication skills and repetitive behaviors caused by different combinations of genetic and environmental... Autism and autism spectrum disorders(ASD) refer to a range of conditions characterized by impaired social and communication skills and repetitive behaviors caused by different combinations of genetic and environmental influences. Although the pathophysiology underlying ASD is still unclear, recent evidence suggests that immune dysregulation and neuroinflammation play a role in the etiology of ASD. In particular, there is direct evidence supporting a role for maternal immune activation during prenatal life in neurodevelopmental conditions. Currently, the available options of behavioral therapies and pharmacological and supportive nutritional treatments in ASD are only symptomatic. Given the disturbing rise in the incidence of ASD, and the fact that there is no effective pharmacological therapy for ASD, there is an urgent need for new therapeutic options. Mesenchymal stem cells(MSCs) possess immunomodulatory properties that make them relevant to several diseases associated with inflammation and tissue damage. The paracrine regenerative mechanisms of MSCs are also suggested to be therapeutically beneficial for ASD.Thus the underlying pathology in ASD, including immune system dysregulation and inflammation, represent potential targets for MSC therapy. This review willfocus on immune dysfunction in the pathogenesis of ASD and will further discuss the therapeutic potential for MSCs in mediating ASD-related immunological disorders. 展开更多
关键词 AUTISM spectrum DISORDERS MESENCHYMAL stem cells Major HISTOCOMPATIBILITY complex Inflammation MATERNAL immune activation Cell therapy
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A Fault-Tolerant Cooperative Spectrum Sensing Algorithm over Cognitive Radio Network Based on Wireless Sensor Network
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作者 Mohammad Akbari Abolfazl Falahati 《Wireless Sensor Network》 2011年第3期83-91,共9页
A serious threat to cognitive radio networks that sense the spectrum in a cooperative manner is the transmission of false spectrum sensing data by malicious sensor nodes. SNR fluctuations due to wireless channel effec... A serious threat to cognitive radio networks that sense the spectrum in a cooperative manner is the transmission of false spectrum sensing data by malicious sensor nodes. SNR fluctuations due to wireless channel effects complicate handling such attackers even further. This enforces the system to acquire authentication. Actually, the decision maker needs to determine the reliability or trustworthiness of the shared data. In this paper, the evaluation process is considered as an estimation dilemma on a set of evidences obtained through sensor nodes that are coordinated in an underlying wireless sensor network. Then, a likelihood-based computational trust evaluation algorithm is proposed to determine the trustworthiness of each sensor node's data. The proposed procedure just uses the information which is obtained from the sensor nodes without any presumptions about node’s reliability. Numerical results confirm the effectiveness of the algorithm in eliminating malicious nodes or faulty nodes which are not necessarily conscious attackers. 展开更多
关键词 Cognitive Radio NETWORK (CRN) Cooperative spectrum Sensing Wireless Sensor NETWORK (WSN) TRUST Evaluation Maximum LIKELIHOOD Estimation (MLE)
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奇异谱分析在太阳10.7cm射电流量中期预测中的应用 被引量:7
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作者 钟秋珍 刘四清 +1 位作者 何卷雄 龚建村 《空间科学学报》 CAS CSCD 北大核心 2005年第3期199-203,共5页
首次尝试利用信号处理技术奇异谱分析方法预测太阳活动低年未来27天太阳10.7cm射电流量.选取的预报试验时间段是2004年4月30日至5月30日,此试验期内太阳活动水平相对较低.在样本时间序列的构建上,吸取了相似周数据分析思路,采取的是23... 首次尝试利用信号处理技术奇异谱分析方法预测太阳活动低年未来27天太阳10.7cm射电流量.选取的预报试验时间段是2004年4月30日至5月30日,此试验期内太阳活动水平相对较低.在样本时间序列的构建上,吸取了相似周数据分析思路,采取的是23周实时观测数据与其相似周第20周下降年部分数据相结合的方式,既增加了样本长度又避开了太阳活动的活跃期.这31天的预报试验结果表明,大部分情况下,预报值基本上体现出F10.7的变化趋势,平均相对误差为10.5%;比同时期美国空军预测值的平均相对误差小,前者为11.3%,后者为14.6%;除两天外,SSA每一次27天的预报结果的平均相对误差比美国空军(AAF)的要小;对不同的时间提前量而言,AAF提前1天到提前12天的预报准确性较奇异谱分析方法要高,即AAF较短期的预报效果更好. 展开更多
关键词 20044 23
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麦蚜对小麦冠层光谱特性的影响研究 被引量:30
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作者 乔红波 程登发 +3 位作者 孙京瑞 田喆 陈林 林芙蓉 《植物保护》 CAS CSCD 北大核心 2005年第2期21-26,共6页
通过对田间不同程度麦蚜危害的小麦冠层反射光谱测量,研究了各波段反射光谱的变异特征,并对光谱反射曲线进行微分分析。结果表明:在麦蚜危害的初期,近红外反射率明显降低,即陡坡效应受到明显的削弱,随着麦蚜危害程度加重,小麦冠层的反... 通过对田间不同程度麦蚜危害的小麦冠层反射光谱测量,研究了各波段反射光谱的变异特征,并对光谱反射曲线进行微分分析。结果表明:在麦蚜危害的初期,近红外反射率明显降低,即陡坡效应受到明显的削弱,随着麦蚜危害程度加重,小麦冠层的反射率在不同波段有明显下降,尤其在近红外区下降更为显著。利用光谱微分技术,对受麦蚜不同程度危害的小麦冠层反射率求一阶导数,得到红边斜率。结果表明,麦蚜危害后小麦冠层的红边斜率在近红外波段发生剧烈的变化,且随着危害程度的加重其值逐步下降。将归一化植被指数(NDVI)分别和百株蚜量进行相关及回归分析,并对监测蚜虫敏感波段的选择做了初步的探讨。 展开更多
关键词 线
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核质互作不育和光敏核不育聚合的粳稻不育系选育 被引量:15
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作者 王守海 杜士云 +1 位作者 王德正 李成荃 《中国农业科学》 CAS CSCD 北大核心 2005年第7期1289-1294,共6页
针对粳型核质互作不育系高温自交结实和粳型光敏核不育系低温自交结实的现状,选择BT型核质互作不育系与含有BT型保持基因的粳型光敏核不育系,通过杂交和回交,使雄性核不育基因与核质互作不育基因聚合,育成了粳型光敏核质互作不育系2308S... 针对粳型核质互作不育系高温自交结实和粳型光敏核不育系低温自交结实的现状,选择BT型核质互作不育系与含有BT型保持基因的粳型光敏核不育系,通过杂交和回交,使雄性核不育基因与核质互作不育基因聚合,育成了粳型光敏核质互作不育系2308SA和2310SA。该不育系的不育性是由两套相互独立的基因系统控制的,分期播种育性观察结果表明,在长日高温下,雄性光敏核不育隐性纯合基因控制水稻不育性,避免了BT型不育基因因穗期受高温影响而导致不育系自交结实;在长日适温下,水稻不育性由核不育基因和核质互作不育基因共同控制而表现稳定;在低温(低于光敏不育系不育临界温度)或短日适温(日最高气温<32℃)下,BT型核质互作不育基因控制水稻不育性,消除了育性敏感期低温导致核不育系“打摆子”造成杂交种子不纯的风险。还对粳型光敏感核质互作不育系的可恢性、可繁性和配合力进行了研究。 展开更多
关键词 BT
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Identification of the interactive region by the homology of the sequence spectrum
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作者 Masatoshi Nakahara Masaharu Takeda 《Journal of Biomedical Science and Engineering》 2010年第9期868-883,共16页
The base sequence in genome was governed by some fundamental principles such as reverse-complement symmetry, multiple fractality and so on, and the analytical method of the genome structure, the “Sequence Spectrum Me... The base sequence in genome was governed by some fundamental principles such as reverse-complement symmetry, multiple fractality and so on, and the analytical method of the genome structure, the “Sequence Spectrum Method (SSM)”, based on the structural features of genomic DNA faithfully visualized these principles. This paper reported that the sequence spectrum in SSM closely reflected the biological phenomena of protein and DNA, and SSM could identify the interactive region of protein-protein and DNA-protein uniformly. In order to investigate the effectiveness of SSM we analyzed the several protein-protein and DNA-protein interaction published primarily in the genome of Saccharomyces cerevisiae. The method proposed here was based on the homology of sequence spectrum, and it advantageously and surprisingly used only base sequence of genome and did not require any other information, even information about the amino-acid sequence of protein. Eventually it was concluded that the fundamental principles in genome governed not only the static base sequence but also the dynamic function of protein and DNA. 展开更多
关键词 spectrum of GENOME Base SEQUENCE HOMOLOGY of SEQUENCE spectrum Interactive Region Reverse-Complement Symmetry Multiple FRACTALITY Analytical Method Of GENOME
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用密度泛函理论研究一种新型有机硅化合物异构体的振动光谱 被引量:9
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作者 赵一新 崔孟忠 +1 位作者 唐小真 王曙光 《化学学报》 SCIE CAS CSCD 北大核心 2005年第14期1257-1262,i001,共7页
在B3LYP/6-31+G(d)的水平上,对两种含有手性Si原子的新型有机硅单体Si_2(CH_3)_2H_2N_2(C_2H_5)_4和Si_4(CH_3)_4H_4N_2(C_6H_5)_2的几种异构体进行了研究,在全参量几何构型优化的基础上,进行了简谐振动频率计算,同时对所研究的体系进... 在B3LYP/6-31+G(d)的水平上,对两种含有手性Si原子的新型有机硅单体Si_2(CH_3)_2H_2N_2(C_2H_5)_4和Si_4(CH_3)_4H_4N_2(C_6H_5)_2的几种异构体进行了研究,在全参量几何构型优化的基础上,进行了简谐振动频率计算,同时对所研究的体系进行了热力学性质和低能激发态的含时密度泛函理论(TDDFT)计算.理论计算表明,构象异构体之间的红外光谱差异不大,热力学和低能激发态性质也相似;顺/反结构相似的异构体之间红外光谱差异不大,但热力学和低能激发态性质却呈现差异;旋光异构体或顺/反结构相差较大的异构体之间,红外光谱和热力学及低能激发态性质有明显的差异.从理论上解释了实验红外光谱中Si—H振动峰的裂分是由异构体的存在所致,并找到裂分峰所对应的异构结构.Si—H键振动频率与其键长相关. 展开更多
关键词 B3LYP
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