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Association of conventional chromosomal polymorphic variants in 580 couples with idiopathic recurrent pregnancy loss:A retrospective cohort study
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作者 Sunny Kumar Jignesh Kumar Patel Amit Roy Chowdhury +2 位作者 Shagufa Sheikh Purna Chandra Mahapatra Birendranath Banerjee 《Asian pacific Journal of Reproduction》 2026年第1期11-22,共12页
Objective:To investigate the potential link between chromosomal polymorphisms in couples who had a medical history of idiopathic recurrent pregnancy loss.Methods:Cytogenetic investigation was conducted with mitogen(Ph... Objective:To investigate the potential link between chromosomal polymorphisms in couples who had a medical history of idiopathic recurrent pregnancy loss.Methods:Cytogenetic investigation was conducted with mitogen(Phytohemagglutinin-M,Gibco)stimulated blood T lymphocytes by Giemsa trypsin Giemsa banding and Ag-NOR banding on 580 couples with a history of idiopathic recurrent pregnancy loss and 240 couples from the general population.Thirty good chromosomal spreads were captured,karyotyped,and analyzed.The karyotypes were designated using the International System for Human Cytogenomic Nomenclature 2024.Pearson Chi-square test was used to compare the frequency of chromosomal polymorphism variations in the idiopathic recurrent pregnancy loss group with the general population group.Results:A conventional cytogenetic investigation revealed that 45.43%of couples experiencing idiopathic recurrent pregnancy loss presented with various types of chromosomal polymorphic variants,compared to 11.88%in the general population.The overall frequency of these chromosomal polymorphic variants was significantly higher in the idiopathic recurrent pregnancy loss group compared to the general population group(OR 9.97,95%CI 6.99-14.21;P<0.05).Additionally,the prevalence of polymorphic variants was higher among males(49.14%)than females(41.72%)(P=0.01).Conclusions:Chromosomal polymorphic analysis may play a crucial role in the assessment and careful clinical management of cases with idiopathic recurrent pregnancy loss,especially when no other conclusive reasons are identified during the initial evaluation.Therefore,heteromorphism should not be overlooked while investigating the causes of idiopathic recurrent pregnancy loss. 展开更多
关键词 polymorphic variants Chromosomal anomalies Repeated pregnancy loss Cytogenetic investigation
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Deciphering performance heterogeneity and polymorphic transformation in siliceous ramming materials:a mechanistic exploration
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作者 Ben-Jun Cheng Wei-Bin Xu +3 位作者 Zhong-Fei Liu Feng Wu Guo-Qi Liu Xiao-Cheng Liang 《Journal of Iron and Steel Research International》 2026年第3期45-59,共15页
As a distinctive unshaped refractory material used in steelmaking induction furnace linings,significant variations in raw material performance,particularly erosion resistance,have been observed across silica sources f... As a distinctive unshaped refractory material used in steelmaking induction furnace linings,significant variations in raw material performance,particularly erosion resistance,have been observed across silica sources from different regions.To clarify the causes of performance discrepancies and reveal the erosion resistance mechanisms,erosion resistance experiments were conducted on three quartzite raw materials from distinct regions.Furthermore,the enhancement effects of mineralizers on the raw material with the poorest performance were investigated,and the erosion resistance mechanisms of representative raw materials and mineralization effects in silica ramming materials were proposed.The results demonstrated that the presence of dolomite and iron oxide in raw materials is critical for improving the erosion resistance of silica ramming materials.However,the material with 1 wt.%dolomite as a standalone mineralizer exhibited optimal erosion resistance compared to iron oxide composite mineralizers.This improvement is attributed to the formation of uniformly distributed tridymite and an appropriate liquid phase,which mitigates volume expansion effects caused by quartz phase transformation,thereby minimizing aggregate cracking.Additionally,magnesium derived from dolomite plays a specialized role in the operational environment,with the synergistic effects of these two factors collectively enhancing the material’s erosion resistance. 展开更多
关键词 SILICA Unshaped refractory Mineralization mechanism Quartz polymorphic transformation Erosion resistance
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Structural and Phase Engineering in Two-Dimensional Polymorphic In_(2)Se_(3)
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作者 Ming Yang Guang Wang +4 位作者 Bo Li Yayun Yu Bowen Yao Zhihui Qin Jiayu Dai 《Chinese Physics Letters》 2025年第12期239-252,共14页
The two-dimensional van der Waals layered semiconductor In_(2)Se_(3) has emerged as a promising candidate for non-volatile ferroelectric memory,optoelectronic devices,and polymorphic phase engineering.Polymorphic In_(... The two-dimensional van der Waals layered semiconductor In_(2)Se_(3) has emerged as a promising candidate for non-volatile ferroelectric memory,optoelectronic devices,and polymorphic phase engineering.Polymorphic In_(2)Se_(3) typically stabilizes in three distinct phases:α-,β′-,and β^(*)-In_(2)Se_(3),each dominant within specific temperature ranges.Although the crystal structures and ferroelectric properties of these phases have been widely studied,the unambiguous assignment of their in-plane and out-of-plane ferroelectric behaviors,as well as the mechanisms governing their phase transitions,remains a subject of active debate.In this study,we investigate the evolution of atomic and electronic structures in molecular beam epitaxy-grown ultrathin In_(2)Se_(3) films through correlated microstructural and macroscopic physical property analysis.By employing scanning tunneling microscopy/spectroscopy,temperature-dependent Raman spectroscopy,and piezoresponse force microscopy,we demonstrate a reversible temperature-induced phase transition between the in-plane ferroelectric β^(*)and antiferroelectric β′phases.Furthermore,we confirm robust out-of-plane ferroelectric polarization in the as-grown films and achieve an electric-field-driven transition from the β^(*)to β′phase.Our findings not only advance the fundamental understanding of phase transitions and polarization evolution in two-dimensional semiconductors but also open new avenues for the design of tunable,non-volatile ferroelectric memory devices. 展开更多
关键词 polymorphic phase engineeringpolymorphic structural engineering optoelectronic devices two dimensional polymorphic ferroelectric properties SE crystal structures phase engineering
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Polymorphic reactive oxygen species(ROS)storm for enhanced tumor therapy
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作者 Yanhong Sun Sihuai Xiong +10 位作者 Xingwu Jiang Jing Jin Tianlin Song Fan Wu Fei Chen Di Wu Yuanchen Wang Xianfu Meng Wenbin Zou Zhuan Liao Wenbo Bu 《Rare Metals》 2025年第11期8732-8743,共12页
Generating excessively reactive oxygen species(ROS)within tumor cells is a widely adopted therapeutic strategy.However,single-type ROS exhibit fixed attack sites and mechanisms of action in tumor cells,rendering them ... Generating excessively reactive oxygen species(ROS)within tumor cells is a widely adopted therapeutic strategy.However,single-type ROS exhibit fixed attack sites and mechanisms of action in tumor cells,rendering them susceptible to resistance via cellular repair mechanisms.To overcome this limitation,this study proposes a polymorphic ROS strategy that simultaneously induces multiple types of ROS to enhance the therapeutic efficacy.A nanoplatform named as AuPd@Mn_(x)O_(y)/L/DOX(APM@L/D)is developed.AuPd core can catalyze oxygen to generate superoxide anions(O_(2)^(·-)),and the released multivalent manganese ions in tumor can trigger the production of singlet oxygen(^(1)O_(2))and hydroxyl radicals(·OH).The polymorphic ROS(O_(2)^(·-),^(1)O_(2),·OH)with different reactivity,lifetime,and diffusion capacity can achieve multifaceted oxidative damage,significantly improving tumor eradication.Concurrently,photothermal heating and DOX release can enhance catalytic reaction rate and intracellular hydrogen peroxide levels,further amplifying polymorphic ROS generation.Both in vitro and in vivo experiments demonstrate that AP-M@L/D induces significant intracellular oxidative stress and enhances cell-killing efficiency by activating the apoptotic pathway.In summary,the spatiotemporally controllable polymorphic ROS can enhance antitumor efficacy and provide a guidance for ROS therapy. 展开更多
关键词 polymorphic ROS APOPTOSIS Oxidative damage
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Polymorphic variants in GABA-A receptor and their association with epilepsy and drug resistance:A North Indian cohort study
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作者 Pradeep Kumar Dabla Swati Singh +5 位作者 Aroop Viswas Swapan Gupta Manisha Yadav Subash C Sonkar BidhanC Koner Nafija Serdarevic 《World Journal of Psychiatry》 2025年第11期269-275,共7页
BACKGROUND Gamma-aminobutyric acid type A receptor has long been acknowledged as a key target in the pathophysiology of epilepsy.The GABRA1 and GABRG2 genes encode the α1 and γ2 subunits of the gamma-aminobutyric ac... BACKGROUND Gamma-aminobutyric acid type A receptor has long been acknowledged as a key target in the pathophysiology of epilepsy.The GABRA1 and GABRG2 genes encode the α1 and γ2 subunits of the gamma-aminobutyric acid type A receptor,a key protein implicated in the development of epilepsy.However,the specific association of the GABRA1 IVS11+15 A>G rs2279020 and GABRG2 G3145A rs211013 polymorphisms with antiepileptic drug resistance has been elucidated in only a limited number of investigations.AIM To elucidate the association between GABRA1 IVS11+15 A>G rs2279020 and GABRG2 G3145A rs211013 gene mutations and drug resistance in epilepsy patients.METHODS A total of 100 epilepsy patients(50 drug responsive and 50 drug resistant subjects)were recruited and rs2279020-and rs211013-polymorphism analyzed by restriction fragment length polymorphism-polymerase chain reaction technique.RESULTS For GABRA1 rs2279020 polymorphism,AG genotype exhibited risk association with an odds ratio of 0.966(95%confidence interval=0.346-2.698)with P value=0.948;however,this association did not achieve statistical significance(P=0.948).Additionally,a higher risk association was identified with the GG genotype,with an odds ratio of 1.808(P=0.382).GABRG2 rs211013 polymorphism revealed no significant association with drug resistance.CONCLUSION The GABRA1 rs2279020 genetic variation is associated with an increased risk for the AG and GG variants,although this association was not statistically significant.Limited investigations have explored the relevance of genetic variations in epilepsy and drug resistance.Longitudinal research is needed to better understand their significance in epilepsy management and to optimize therapeutic strategies. 展开更多
关键词 EPILEPSY Single nucleotide polymorphism Drug-resistant epilepsy Gamma-aminobutyric acid type A receptor GABRA1 rs2279020 GABRG2 rs211013
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Substantia nigra-related gene polymorphisms associated with acute antipsychotic-induced movement disorders
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作者 Kenji Hashimoto 《Military Medical Research》 2026年第2期338-339,共2页
Antipsychotics,especially many second-generation antipsychotics(SGAs),remain central to schizophrenia treatment,are indispensable in acute mania and for bipolar maintenance(with selected roles in bipolar depression),a... Antipsychotics,especially many second-generation antipsychotics(SGAs),remain central to schizophrenia treatment,are indispensable in acute mania and for bipolar maintenance(with selected roles in bipolar depression),and serve as evidence-based augmenters in treatment-resistant depression.Nonetheless,acute antipsychotic-induced movement disorders(AIMDs)[extrapyramidal symptoms(EPS)]are common and clinically costly,impairing quality of life,adherence,and outcomes.The acute spectrum is dominated by dystonia(sustained,often painful contractions). 展开更多
关键词 ANTIPSYCHOTIC Movement disorder polymorphISM Substantia nigra
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Random Amplified Polymorphic DNA (RAPD) Markers on Genomic DNA Polymorphism in 8 Main Grasshoppers in Inner Mongolia
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作者 高书晶 刘爱萍 +1 位作者 李东伟 闫志坚 《Plant Diseases and Pests》 CAS 2010年第4期28-31,57,共5页
[ Objective] The relationship between the genetic evolution and phylogenesis of the main grasshopper species in Inner Mongolia grasslands in molecular level was studied. [ Method] Random amplified polymorphic DNA (R... [ Objective] The relationship between the genetic evolution and phylogenesis of the main grasshopper species in Inner Mongolia grasslands in molecular level was studied. [ Method] Random amplified polymorphic DNA (RAPD) technique was used to amplify the 80 individuals of 8 grasshoppers (4 families, 6 genera) in Acridoidea, the polymorphisms of their genomic DNA were compared. [ Result] 64 specific fragments were amplified by 7 primers with the molecular weight of 300 -2 000 bp. The genetic distance between 8 grasshoppers was 0.228 2 -0.589 6. Band pat- tern showed that polymorphism was commonly existed in different genus within the same family and different species within the same genus. The resuits were conducted UPGMA cluster analysis according to Neis' genetic distance, the results showed that the species within the same genus first clustered together, then the species in the same family clustered together. [ Condusloa] The study could provide molecular biological basis for system development and evolution research of main grasshoppers in Inner Mongolia grassland. 展开更多
关键词 DNA polymorphism RAPD Affinity relationship GRASSHOPPER
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Analysis and modeling of web services flow using π-calculus
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作者 何涛 缪淮扣 钱忠胜 《Journal of Southeast University(English Edition)》 EI CAS 2006年第3期315-318,共4页
In order to increase the effectiveness and the reliability of web services flow, the ~r-calculus formal method is introduced as a development language for web services flow. The π-calculus overcomes inabilities of we... In order to increase the effectiveness and the reliability of web services flow, the ~r-calculus formal method is introduced as a development language for web services flow. The π-calculus overcomes inabilities of web service flow languages in demonstrating the consistency, validating the correctness and so on. The π- calculus analysis and modeling of web services flow is presented, the dynamic actions and basic activities of WS-BPEL with π-calculus formally are described, and the mapping from π-calculus expression to WS-BPEL is built. The basic construction of web services flow with the π-calculus method after the analysis of the syntax of WS-BPEL and inter-description between WS-BPEL and π-calculus is expressed. Also discussed are the approaches to web services flow by modeling from different views, and the proposed approaches through the development and modeling of an e-commerce web service flow application are illustrated. 展开更多
关键词 business process execution language (BPEL) web services work flow Π-calculus
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Analysis of genetic diversity for wild and captive green peafowl populations by random amplified polymorphic DNA technique 被引量:2
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作者 柯亚永 常弘 张国萍 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第3期203-206,共4页
The genetic diversity of the populations for 14 wild green peafowls (Pavo muticus) and 18 captive green pea-fowls was investigated by using the technology of random amplified polymorphic DNA (RAPD). Totally 161 and 16... The genetic diversity of the populations for 14 wild green peafowls (Pavo muticus) and 18 captive green pea-fowls was investigated by using the technology of random amplified polymorphic DNA (RAPD). Totally 161 and 166 ampli-fied bands were obtained by using 23 arbitrary primers to amplify the genomic DNA of wild and captive green peafowls re-spectively. The results showed that the average relative genetic distance of the wild and captive green peafowls popula-tions was 0.0555 and 0.1355, respectively, and difference of the average relative genetic distances between the two popu-lations was 0.1635. The Shannon diversity index for the wild and captive green peafowl populations was 0.4348 and 1.0163, respectively, which means that there exists significant difference in genetic diversity between the two populations, and the genetic diversity of wild green peafowl was low. The two populations originated from two different families according to analysis by the UPGMA method. This research can provide the theoretical basis for supervising genealogies management of peafowl populations. 展开更多
关键词 Green peafowl Pavo muticus Genomic DNA Random amplified polymorphic DNA (RAPD)
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Heavy metal induced DNA changes in aquatic macrophytes: Random amplified polymorphic DNA analysis and identification of sequence characterized amplified region marker 被引量:9
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作者 Meetu Gupta Neera Bhalla Sarin 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第5期686-690,共5页
Plants have been used as good bio-indicators and genetic toxicity of environmental pollution in recent years. In this study, aquatic plants Hydrilla verticillata and Ceratophyllum demersum treated with 10umol/L Cd, 5 ... Plants have been used as good bio-indicators and genetic toxicity of environmental pollution in recent years. In this study, aquatic plants Hydrilla verticillata and Ceratophyllum demersum treated with 10umol/L Cd, 5 umol/L Hg, and 20 umol/L Cu for 96 h, showed changes in chlorophyll, protein content, and in DNA profiles. The changes in DNA profiles included variation in band intensity, presence or absence of certain bands and even appearance of new bands. Genomic template stability test performed for the qualitative measurement of changes in randomly amplified polymorphic DNA (RAPD) profiles, showed significant effect at the given concentration of metals. Cloning and sequencing of bands suggested that these markers although may not be homologous to any known gene but its conversion as a sequence characterized amplified region (SCAR) marker is useful in detecting the effects of genotoxin agents. 展开更多
关键词 RAPD Hydrilla verticillata Ceratophyllum demersum DNA polymorphism SCAR marker
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Meiotic abnormalities in metaphase I human spermatocytes from infertile males: frequencies, chromosomes involved, and relationship with polymorphic karyotype and seminal parameters 被引量:5
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作者 Zaida Sarrate Francesca Vidal Joan Blanco 《Asian Journal of Andrology》 SCIE CAS CSCD 2014年第6期838-844,共7页
The aim of this study was to look in depth at the relationship between meiotic anomalies and male infertility, such as the determination of the chromosomes involved or the correlation with patient features. For this p... The aim of this study was to look in depth at the relationship between meiotic anomalies and male infertility, such as the determination of the chromosomes involved or the correlation with patient features. For this purpose, a total of 31 testicular tissue samples from individuals consulting for fertility problems were analyzed. Metaphase I cells were evaluated using a sequential methodology combining Leishman stained procedures and multiplex fluorescence in situ hybridization protocols. The number of chromosomal units and chiasmata count per bivalent were established and a hierarchical cluster analysis of the individuals was performed. The relationship of the seminogram and the karyotype over recombination were evaluated using Poisson regression models. Results obtained in this study show a significant percentage of infertile individuals with altered meiotic behavior, mostly specified as a reduction in chiasmata count in medium and large chromosomes, the presence of univalents, and the observation of tetraploid metaphases. Moreover, the number and the type of anomalies were found to be different between cells of the same individual, suggesting the coexistence of cell lines with normal meiotic behavior and cell lines with abnormalities. In addition, chromosomal abnormalities in metaphase I are significantly associated with oligozoospermia and/or polymorphic karyotype variants. 展开更多
关键词 chiasmata count human spermatocytes multiplex fluorescence in situ hybridization polymorphic karyotype seminalparameters
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A Cleaved Amplified Polymorphic Sequence Marker to Detect Variation in Wx Locus Conditioning Translucent Endosperm in Rice 被引量:12
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作者 CHEN Tao ZHANG Ya-dong ZHAO Ling ZHU Zhen LIN Jing ZHANG Suo-bing WANG Cai-lin 《Rice science》 SCIE 2009年第2期106-110,共5页
The translucent endosperm trait in a japonica rice variety 'Kantou 194' is controlled by a Wx-mq gene which is allelic to Wx locus by genetic analysis and allelic test. The amylose content analysis showed that an in... The translucent endosperm trait in a japonica rice variety 'Kantou 194' is controlled by a Wx-mq gene which is allelic to Wx locus by genetic analysis and allelic test. The amylose content analysis showed that an intermediate amylose content between those of glutinous and non-glutinous rice existed in endosperm of homozygous Wx-mq genotype. The slight changes of amylose content in different varieties and F1 grains with an identical Wx-mq genotype might be influenced by dissimilar genetic background. To identify the Wx-mq genotype simply and rapidly, a cleaved amplified polymorphic sequence (CAPS) marker was designed. The result from the molecular detection indicated that it could be used for marker-assisted selection for low amylose content varieties in rice breeding. 展开更多
关键词 RICE amylose content translucent endosperm mutant waxy gene molecular marker-assisted selection cleaved amplified polymorphic sequence marker
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Retrieval of leaf biochemical properties by inversed PROSPECT model and hyperspectral indices:an application to Populus euphratica polymorphic leaves 被引量:4
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作者 ZhongGuo MA Xi CHEN +2 位作者 Quan WANG PingHeng LI Guli Jiapaer 《Journal of Arid Land》 SCIE 2012年第1期52-62,共11页
Leaf biochemical properties have been widely assessed using hyperspectral reflectance information by inversion of PROSPECT model or by using hyperspectral indices, but few studies have focused on arid ecosystems. As a... Leaf biochemical properties have been widely assessed using hyperspectral reflectance information by inversion of PROSPECT model or by using hyperspectral indices, but few studies have focused on arid ecosystems. As a dominant species of riparian ecosystems in arid lands, Populus euphratica Oliv. is an unusual tree species with polymorphic leaves along the vertical profile of canopy corresponding to different growth stages. In this study, we evaluated both the inversed PROSPECT model and hyperspectral indices for estimating biochemical properties of P. euphratica leaves. Both the shapes and biochemical properties of P. euphratica leaves were found to change with the heights from ground surface. The results indicated that the model inversion calibrated for each leaf shape performed much better than the model calibrated for all leaf shapes, and also better than hyperspectral indices. Similar results were obtained for estimations of equivalent water thickness (EWT) and leaf mass per area (LMA). Hyperspectral indices identified in this study for estimating these leaf properties had root mean square error (RMSE) and R2 values between those obtained with the two calibration strategies using the inversed PROSPECT model. Hence, the inversed PROSPECT model can be applied to estimate leaf biochemical properties in arid ecosystems, but the calibration to the model requires special attention. 展开更多
关键词 Populus euphratica inversed model hyperspectral index vertical profile polymorphic leaf
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Screening,Preparation,Characterization and Solubility of Polymorphic Forms of Ethinyl Estradiol 被引量:2
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作者 徐娟 王慧萍 +1 位作者 李鹏 宁丽峰 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第6期949-957,共9页
Ethinyl estradiol(EE) as a contraceptive,(17α)-19-nopregna-1,3,5-(10)-trien-20-yne-3,17-diol(formula: C(20)H(24)O2, molecular weight: 296.4, CAS number: 57-63-6), is known to have different pseudo-poly... Ethinyl estradiol(EE) as a contraceptive,(17α)-19-nopregna-1,3,5-(10)-trien-20-yne-3,17-diol(formula: C(20)H(24)O2, molecular weight: 296.4, CAS number: 57-63-6), is known to have different pseudo-polymorphic forms. Some EE polymorphs have been synthesized by means of physical or chemical methods, characterized by X-ray powder diffraction(XRPD), thermogravimetric(TG), differential scanning calorimetry(DSC) and IR spectra. Dissolution profile was tested by high performance liquid chromatography(HPLC). Meanwhile, the crystal structure of the new EE solvate(formamide) was characterized by single-crystal X-ray structure analysis(SXRD). The results confirmed that EE existed polymorphism. Five crystal forms of EE were presented and two of them were reported firstly. Furthermore, five polymorphs' dissolution curves were drawn and they could be identified by several analysis methods. Our study on polymorphs of EE could provide a variety of crystal material composition, preparation methods and solubility. 展开更多
关键词 ethinyl estradiol polymorphISM useful characterization methods dissolutionprofiles96
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Differential Polymorphic Transformation Behavior of Polybutene-1 with Multiple Isotactic Sequences 被引量:11
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作者 Ya-Ping Ma Wei-Ping Zheng +3 位作者 Chen-Guang Liu Hua-Feng Shao Hua-Rong Nie Ai-Hua He 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2020年第2期164-173,I0007,共11页
For the solid-solid transformation from formⅡto formⅠof isotactic polybutene-1(iPB),the temperature dependence of formⅠnucleation and growth was deemed to control the transformation process.However,the relationship... For the solid-solid transformation from formⅡto formⅠof isotactic polybutene-1(iPB),the temperature dependence of formⅠnucleation and growth was deemed to control the transformation process.However,the relationship between formⅠformation and formⅡdisappearance in the transformation process is not clear.In this work,the spontaneous crystal transformation from formⅡtoⅠof iPB with 81 mol%mmmm sequence concentration is studied firstly by tracking the two processes,the decay of formⅡand the yielding of formⅠin a wide range of temperature spanning from 0℃to 50℃and in a long transformation time ranging from 5 min to 65 days with in situ FTIR and WAXD.Unlike the literature reports,the decay rate of formⅡis firstly found to be lower than the yielding rate of formⅠat all studied temperatures,especially at low transition temperature.This is attributed to the amorphous chains which locate near crystal lamella participating into the nucleation of formⅡ.The regular chain folding and growth of i PB formⅠfrom amorphous chains containing short isotactic sequences also lead to an increase in crystallinity of formⅠcompared with that of initial formⅡcrystallized at 60℃.An increase in the annealing temperature results in decrease in crystallinity and increase in lamellae thickness of i PB formⅠ. 展开更多
关键词 POLYBUTENE-1 polymorphic transformation Isotactic sequence CRYSTALLINITY Lamellae thickness
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Theoretical Framework for a Polymorphic Network Environment 被引量:6
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作者 Jiangxing Wu Junfei Li +2 位作者 Penghao Sun Yuxiang Hu Ziyong Li 《Engineering》 SCIE EI CAS CSCD 2024年第8期222-234,共13页
The question of whether an ideal network exists with global scalability in its full life cycle has always been a first-principles problem in the research of network systems and architectures.Thus far,it has not been p... The question of whether an ideal network exists with global scalability in its full life cycle has always been a first-principles problem in the research of network systems and architectures.Thus far,it has not been possible to scientifically practice the design criteria of an ideal network in a unimorphic network system,making it difficult to adapt to known services with clear application scenarios while supporting the ever-growing future services with unexpected characteristics.Here,we theoretically prove that no unimorphic network system can simultaneously meet the scalability requirement in a full cycle in three dimensions—the service-level agreement(S),multiplexity(M),and variousness(V)—which we name as the“impossible SMV triangle”dilemma.It is only by transforming the current network development paradigm that the contradiction between global scalability and a unified network infrastructure can be resolved from the perspectives of thinking,methodology,and practice norms.In this paper,we propose a theoretical framework called the polymorphic network environment(PNE),the first principle of which is to separate or decouple application network systems from the infrastructure environment and,under the given resource conditions,use core technologies such as the elementization of network baselines,the dynamic aggregation of resources,and collaborative software and hardware arrangements to generate the capability of the“network of networks.”This makes it possible to construct an ideal network system that is designed for change and capable of symbiosis and coexistence with the generative network morpha in the spatiotemporal dimensions.An environment test for principle verification shows that the generated representative application network modalities can not only coexist without mutual influence but also independently match well-defined multimedia services or custom services under the constraints of technical and economic indicators. 展开更多
关键词 polymorphic network environment Impossible triangle Network development paradigm Future network
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Influence of Teflon Substrate on Crystallization and Enzymatic Degradation of Polymorphic Poly(butylene adipate) 被引量:1
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作者 Zhen-bo Ning Ronnie Nielsen +2 位作者 Li-fen Zhao Dong-hong Yu 甘志华 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2014年第9期1243-1252,共10页
Oriented and non-oriented Teflon films, which were found to have the same crystalline structure, but different surface morphologies, were used to sandwich poly(butylene adipate) (PBA) films during isothermal cryst... Oriented and non-oriented Teflon films, which were found to have the same crystalline structure, but different surface morphologies, were used to sandwich poly(butylene adipate) (PBA) films during isothermal crystallization. It was found that both the Teflon surface structure and the PBA polymorphic structure are the determining factors to induce epitaxial crystallization. The oriented Teflon film was able to induce epitaxial crystallization of PBA α crystal, while the non-oriented Teflon did not induce any epitaxial crystallization of PBA. Epitaxial crystallization did not occurred for PBA β crystals between neither the oriented nor the non-oriented Teflon films. The enzymatic degradation rate of PBA films was not determined by the epitaxial crystallization, in fact it was still dependent on the polymorphic crystal structure of PBA. The morphological changes of PBA films after enzymatic degradation confirmed again that the epitaxial crystallization only occurred for the PBA film with α crystal structure which was produced by being sandwiched between oriented Teflon films, and it happened only on the surface of PBA films. 展开更多
关键词 Poly(butylene adipate) Epitaxial crystallization polymorphic crystals Enzymatic degradation Morphology.
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Synthesis and Crystal Structure of the Polymorphic Isomer [Cu(dafone)_2(H_2O)_2](Hphth)_2 被引量:1
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作者 HEXue-Yan LIUXun-Gao LIBao-Long ZHANGYong 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2005年第7期831-835,739,共6页
The polymorphic isomer [Cu(dafone)2(H2O)2](Hphth)2 1 (dafone = 4,5- diazafluoren-9-one, phth = 1,2-benzenedicarboxyl) has been synthesized and the structure was determined by single-crystal X-ray diffraction. Crystal ... The polymorphic isomer [Cu(dafone)2(H2O)2](Hphth)2 1 (dafone = 4,5- diazafluoren-9-one, phth = 1,2-benzenedicarboxyl) has been synthesized and the structure was determined by single-crystal X-ray diffraction. Crystal data: C38H26CuN4O12, monoclinic, space group P21/a with a = 11.5863(18), b = 25.512(4), c = 11.878(2) ?, β = 111.696(3)o, V = 3262.1(9) ?3, Mr = 794.17, Z = 4, Dc = 1.617 g/cm3, F(000) = 1628, μ = 0.748 mm-1, R = 0.0603 and wR = 0.1132 for 6878 observed reflections with I > 2σ(I). 1 consists of one [Cu(dafone)2(H2O)2]2+ cation and two monoprotonated 1,2-benzenedicarboxyl (Hphth) anions and forms a two-dimensional hydrogen bond network via intermolecular hydrogen bond interactions between the coordinated water molecules and carboxylato-oxygen atoms from monoprotonated benzenedicarboxyl anions. 展开更多
关键词 crystal structure polymorphISM copper complex 4 5-diazafluoren-9-one benzenedicarboxyl
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Distribution and effects of polymorphic RANTES gene alleles in HIV/HCV coinfection - A prospective cross-sectional study 被引量:3
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作者 Golo Ahlenstiel Agathe Iwan +9 位作者 Jacob Nattermann Karin Bueren Jürgen K Rockstroh Hans H Brackmann Bernd Kupfer Olfert Landt Amnon Peled Tilman Sauerbruch Ulrich Spengler Rainer P Woitas 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第48期7631-7638,共8页
AIM: Chemokines and their receptors are crucial for immune responses in HCV and HIV infection. RANTES gene polymorphisms lead to altered gene expression and influence the natural course of HIV infection. Therefore,the... AIM: Chemokines and their receptors are crucial for immune responses in HCV and HIV infection. RANTES gene polymorphisms lead to altered gene expression and influence the natural course of HIV infection. Therefore,these mutations may also affect the course of HIV/HCV coinfection.METHODS: We determined allele frequencies of RANTES-403 (G→A), RANTES-28 (C→G) and RANTESIN1.1 (T→C) polymorphisms using real-time PCR and hybridization probes in patients with HIV (n = 85), HCV (n= 112), HIV/HCV coinfection (n = 121), and 109 healthy controls. Furthermore, HIV and HCV loads as well as CD4+ and CD8+ cell counts were compared between different RANTES genotypes.RESULTS: Frequencies of RANTES-403 A, RANTES-28 G and RANTES-IN1.1 C alleles were higher in HIV infected patients than in healthy controls (-403: 28.2% vs 15.1%,P = 0.002; -28: 5.4% vs 2.8%, not significant; IN1.1:19.0% vs 11.0%, P = 0.038). In HIV/HCV coinfected patients, these RANTES alleles were less frequent than in patients with HIV infection alone (15.4% P = 0.002;1.7%; P = 0.048; 12.0%; not significant). Frequencies of these alleles were not significantly different between HIV/HCV positive patients, HCV positive patients and healthy controls.CONCLUSION: All three RANTES polymorphisms showed increased frequencies of the variant allele exclusively in patients with HIV monoinfection. The finding that the frequencies of these alleles remained unaltered in HIV/HCV coinfected patients suggests that HCV coinfection interferes with selection processes associated with these alleles in HIV infection. 展开更多
关键词 RANTES polymorphism HIV/HCV-coinfectJon HCV
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