Objective:To analyze the clinical value of non-invasive prenatal testing(NIPT)in detecting chromosomal copy number variations(CNVs)and to explore the relationship between gene expression and clinical manifestations of...Objective:To analyze the clinical value of non-invasive prenatal testing(NIPT)in detecting chromosomal copy number variations(CNVs)and to explore the relationship between gene expression and clinical manifestations of chromosomal copy number variations.Methods:3551 naturally conceived singleton pregnant women who underwent NIPT were included in this study.The NIPT revealed abnormalities other than sex chromosome abnormalities and trisomy 13,18,and 21.Pregnant women with chromosome copy number variations underwent genetic counseling and prenatal ultrasound examination.Interventional prenatal diagnosis and chromosome microarray analysis(CMA)were performed.The clinical phenotypes and pregnancy outcomes of different prenatal diagnoses were analyzed.Additionally,a follow-up was conducted by telephone to track fetal development after birth,at six months,and one year post-birth.Results:A total of 53 cases among 3551 cases showed chromosomal copy number variation.Interventional prenatal diagnosis was performed in 36 cases:27 cases were negative and 8 were consistent with the NIPT test results.This indicates that NIPT’s positive predictive value(PPV)in CNVs is 22.22%.Conclusion:NIPT has certain clinical significance in screening chromosome copy number variations and is expected to become a routine screening for chromosomal microdeletions and microduplications.However,further interventional prenatal diagnosis is still needed to identify fetal CNVs.展开更多
INTRODUCTION A lot 0fwork has been done on the variation of natural ^(15)N abundance in soils andtheir N components (Chen et al., 1964). However, these reports mostly concerned thegeochemical mean of natural ^(15)N ab...INTRODUCTION A lot 0fwork has been done on the variation of natural ^(15)N abundance in soils andtheir N components (Chen et al., 1964). However, these reports mostly concerned thegeochemical mean of natural ^(15)N abundance, and only a little work has been done on thecharacteristics of variation of the natural ^(15)N abundance in different ecosystems and itsrelationship with the properties and conditions of soil, which is the aim of our recent re-展开更多
Background:The nitrogen isotope natural abundance(δ^(15)N)provides integrated information on ecosystem N dynamics,and carbon isotope natural abundance(δ^(13)C)has been used to infer how water-using processes of plan...Background:The nitrogen isotope natural abundance(δ^(15)N)provides integrated information on ecosystem N dynamics,and carbon isotope natural abundance(δ^(13)C)has been used to infer how water-using processes of plants change in terrestrial ecosystems.However,howδ^(13)C andδ^(15)N abundances in plant life and soils respond to N addition and water availability change is still unclear.Thus,δ^(13)C andδ^(15)N abundances in plant life and soils were used to investigate the effects of long-time(10 years)N addition(+50 kg N·ha^(−1)·yr^(−1)and precipitation reduction(−30%of throughfall)in forest C and N cycling traits in a temperate forest in northern China.Results:We analyzed theδ^(13)C andδ^(15)N values of dominant plant foliage,litterfall,fungal sporophores,roots,and soils in the study.The results showed thatδ^(15)N values of foliage,litterfall,and surface soil layer’s(0–10 cm)total N were significantly increased by N addition,whileδ^(15)N values of fine roots and coarse roots were considerably decreased.Nitrogen addition also significantly increased theδ^(13)C value of fine roots and total N concentration of the surface soil layer compared with the control.The C concentration,δ^(13)C,andδ^(15)N values of foliage andδ^(15)N values of fine roots were significantly increased by precipitation reduction,while N concentration of foliage and litterfall significantly decreased.The combined effects of N addition and precipitation reduction significantly increased theδ^(13)C andδ^(15)N values of foliage as well as theδ^(15)N values of fine roots andδ^(13)C values of litterfall.Furthermore,foliarδ^(15)N values were significantly correlated with foliageδ^(13)C values,surface soilδ^(15)N values,surface soil C concentration,and N concentrations.Nitrogen concentrations andδ^(13)C values of foliage were significantly correlated withδ^(15)N values and N concentrations of fine roots.Conclusions:This indicates that plants increasingly take up the heavier 15N under N addition and the heavier 13C and 15N under precipitation reduction,suggesting that N addition and precipitation reduction may lead to more open forest ecosystem C and N cycling and affect plant nutrient acquisition strategies.展开更多
A Objective3 This study was to understand the genetic variation characters of the H9N2 subtype avian influenza virus isolate (A/Chicken/ Hebei/WD/98, abbreviated as WD98) by comparing with other reference strains. I...A Objective3 This study was to understand the genetic variation characters of the H9N2 subtype avian influenza virus isolate (A/Chicken/ Hebei/WD/98, abbreviated as WD98) by comparing with other reference strains. I-Method3 Eight complete genes were amplified by RT-PCR and sequenced. The homology and genetic evolution relationship were analyzed between these sequences and that of the seven reference strains. [Result] The whole genomic sequence of WD98 strain was 91.1% -95.8% homologous to that of seven reference strains tested. This isolate shared the highest homology (95.8%) to D/HK/Y280/97 and the lowest homology (91.1% ) to C/Pak/2/99. The HA cleavage site of the WD98 strain was R-S-S-R G, and the 226th amino acid at receptor-binding site was Gin. [ Condmion] WD98 strain belongs to mildly pathogenic avian in- fluenza virus and may not infect human. The genetic relationship is the closest between A/Chicken/Hebei/wD/98 and A/duck/HongKong/Y280/ 97, both of which belong to the sub-line of A/Chicken/Beijing/1/94 in Eurasian line. And A/Chicken/Hebei/WD/98 and A/Chicken/Beijing/1/94 are genetically distant within the same sub-line.展开更多
The Coefficient of Variation(CV)of hectometer yarn's weight is one of the guidelines to evaluate its intrinsic quality.In the spinning manufacturing,the control of cotton yarn's weight unevenness is accomplish...The Coefficient of Variation(CV)of hectometer yarn's weight is one of the guidelines to evaluate its intrinsic quality.In the spinning manufacturing,the control of cotton yarn's weight unevenness is accomplished mainly in terms of a spot-check on semi-product and a succedent adjust in process parameters during spinning based on technicians' experience.However,it is theoretically believed among manufacturers that with fixed technical levels and parameters in the spinning process,the quality parameters of assorted cotton have a certain influence on the CV.In order to find out a rule of the influence that assorted cotton has on the CV,a GM(1,N)model,correlated raw cotton's quality parameter with the CV,has firstly been developed according to the modeling theory of grey system,and then been applied in the designing step to predict the CV.It has been approved by practical modeling and validation that the model could fit preferably an accrual CV value,and provide a method of quantitative predicting analysis for textile manufacturers to design cotton yarn's quality.展开更多
基金Dongguan City Social Development Project(Project number:20161081101023)。
文摘Objective:To analyze the clinical value of non-invasive prenatal testing(NIPT)in detecting chromosomal copy number variations(CNVs)and to explore the relationship between gene expression and clinical manifestations of chromosomal copy number variations.Methods:3551 naturally conceived singleton pregnant women who underwent NIPT were included in this study.The NIPT revealed abnormalities other than sex chromosome abnormalities and trisomy 13,18,and 21.Pregnant women with chromosome copy number variations underwent genetic counseling and prenatal ultrasound examination.Interventional prenatal diagnosis and chromosome microarray analysis(CMA)were performed.The clinical phenotypes and pregnancy outcomes of different prenatal diagnoses were analyzed.Additionally,a follow-up was conducted by telephone to track fetal development after birth,at six months,and one year post-birth.Results:A total of 53 cases among 3551 cases showed chromosomal copy number variation.Interventional prenatal diagnosis was performed in 36 cases:27 cases were negative and 8 were consistent with the NIPT test results.This indicates that NIPT’s positive predictive value(PPV)in CNVs is 22.22%.Conclusion:NIPT has certain clinical significance in screening chromosome copy number variations and is expected to become a routine screening for chromosomal microdeletions and microduplications.However,further interventional prenatal diagnosis is still needed to identify fetal CNVs.
基金Project supported by the National Natural Science Foundation of China.
文摘INTRODUCTION A lot 0fwork has been done on the variation of natural ^(15)N abundance in soils andtheir N components (Chen et al., 1964). However, these reports mostly concerned thegeochemical mean of natural ^(15)N abundance, and only a little work has been done on thecharacteristics of variation of the natural ^(15)N abundance in different ecosystems and itsrelationship with the properties and conditions of soil, which is the aim of our recent re-
基金from National Natural Science Foundation of China(Grant Nos:41773075,41575137,31370494,31170421).
文摘Background:The nitrogen isotope natural abundance(δ^(15)N)provides integrated information on ecosystem N dynamics,and carbon isotope natural abundance(δ^(13)C)has been used to infer how water-using processes of plants change in terrestrial ecosystems.However,howδ^(13)C andδ^(15)N abundances in plant life and soils respond to N addition and water availability change is still unclear.Thus,δ^(13)C andδ^(15)N abundances in plant life and soils were used to investigate the effects of long-time(10 years)N addition(+50 kg N·ha^(−1)·yr^(−1)and precipitation reduction(−30%of throughfall)in forest C and N cycling traits in a temperate forest in northern China.Results:We analyzed theδ^(13)C andδ^(15)N values of dominant plant foliage,litterfall,fungal sporophores,roots,and soils in the study.The results showed thatδ^(15)N values of foliage,litterfall,and surface soil layer’s(0–10 cm)total N were significantly increased by N addition,whileδ^(15)N values of fine roots and coarse roots were considerably decreased.Nitrogen addition also significantly increased theδ^(13)C value of fine roots and total N concentration of the surface soil layer compared with the control.The C concentration,δ^(13)C,andδ^(15)N values of foliage andδ^(15)N values of fine roots were significantly increased by precipitation reduction,while N concentration of foliage and litterfall significantly decreased.The combined effects of N addition and precipitation reduction significantly increased theδ^(13)C andδ^(15)N values of foliage as well as theδ^(15)N values of fine roots andδ^(13)C values of litterfall.Furthermore,foliarδ^(15)N values were significantly correlated with foliageδ^(13)C values,surface soilδ^(15)N values,surface soil C concentration,and N concentrations.Nitrogen concentrations andδ^(13)C values of foliage were significantly correlated withδ^(15)N values and N concentrations of fine roots.Conclusions:This indicates that plants increasingly take up the heavier 15N under N addition and the heavier 13C and 15N under precipitation reduction,suggesting that N addition and precipitation reduction may lead to more open forest ecosystem C and N cycling and affect plant nutrient acquisition strategies.
基金supported by subproject of National Program on Key Basic Research Project (973 Program )(2005CB523001)
文摘A Objective3 This study was to understand the genetic variation characters of the H9N2 subtype avian influenza virus isolate (A/Chicken/ Hebei/WD/98, abbreviated as WD98) by comparing with other reference strains. I-Method3 Eight complete genes were amplified by RT-PCR and sequenced. The homology and genetic evolution relationship were analyzed between these sequences and that of the seven reference strains. [Result] The whole genomic sequence of WD98 strain was 91.1% -95.8% homologous to that of seven reference strains tested. This isolate shared the highest homology (95.8%) to D/HK/Y280/97 and the lowest homology (91.1% ) to C/Pak/2/99. The HA cleavage site of the WD98 strain was R-S-S-R G, and the 226th amino acid at receptor-binding site was Gin. [ Condmion] WD98 strain belongs to mildly pathogenic avian in- fluenza virus and may not infect human. The genetic relationship is the closest between A/Chicken/Hebei/wD/98 and A/duck/HongKong/Y280/ 97, both of which belong to the sub-line of A/Chicken/Beijing/1/94 in Eurasian line. And A/Chicken/Hebei/WD/98 and A/Chicken/Beijing/1/94 are genetically distant within the same sub-line.
基金Hunan Provincial Basic Science Foundation of China(No.2007FJ3046)Key Scientific Research Fundof Hunan Provincial Education Department,China(No.07A048)
文摘The Coefficient of Variation(CV)of hectometer yarn's weight is one of the guidelines to evaluate its intrinsic quality.In the spinning manufacturing,the control of cotton yarn's weight unevenness is accomplished mainly in terms of a spot-check on semi-product and a succedent adjust in process parameters during spinning based on technicians' experience.However,it is theoretically believed among manufacturers that with fixed technical levels and parameters in the spinning process,the quality parameters of assorted cotton have a certain influence on the CV.In order to find out a rule of the influence that assorted cotton has on the CV,a GM(1,N)model,correlated raw cotton's quality parameter with the CV,has firstly been developed according to the modeling theory of grey system,and then been applied in the designing step to predict the CV.It has been approved by practical modeling and validation that the model could fit preferably an accrual CV value,and provide a method of quantitative predicting analysis for textile manufacturers to design cotton yarn's quality.