Background:The supine position is the most common birth position adopted in China,but the World Health Organization recommends non-supine positions for delivery.The handsand-knees position shows several advantages,suc...Background:The supine position is the most common birth position adopted in China,but the World Health Organization recommends non-supine positions for delivery.The handsand-knees position shows several advantages,such as wide pelvic diameter and easy fetal rotation during delivery.Small trials conducted in China in 2011 revealed that the handsand-knees position resulted in improved maternal and neonate outcomes than those in the supine position.However,a comprehensive study must be conducted before the handsand-knees position can be introduced into clinical practice.Hence,we conducted this multicenter trial to comprehensively examine the benefits of the hands-and-knees position over the supine position during delivery.Methods:Our clinical study was conducted in 11 hospitals in China from May to December 2012.A total of 446 pregnant women who gave birth in the hands-and-knees position were assigned into the experimental group,and 440 women who gave birth in the supine position were classified into the control group.Episiotomy rate was evaluated as the primary outcome,and perineum laceration degree was considered the secondary outcome.Results:Women in the experimental group achieved lower rates of episiotomy and higher rates of intact perineum and first-degree perineum lacerations compared with those in the control.Postpartum bleeding amount,neonatal asphyxia,and APGAR scores at 1 and 5 min were not significantly different between the two groups.Conclusions:This study proves that women who delivered in the hands-and-knees position achieved low rates of episiotomy and intact perineum.Moreover,the rates of neonatal asphyxia and postpartum bleeding did not increase.Pregnant patients who prefer to adopt the hands-and-knees position should be assisted in assuming such position during delivery.展开更多
CrAlYN coatings with different Y contents(0,5 and 12 at.%)were deposited by cathodic arc evaporation to investigate the influence of Y-addition on the structure,mechanical and thermal properties of CrAlN coatings by u...CrAlYN coatings with different Y contents(0,5 and 12 at.%)were deposited by cathodic arc evaporation to investigate the influence of Y-addition on the structure,mechanical and thermal properties of CrAlN coatings by using X-ray diffraction,scanning electron microscopy,differential scanning calorimetry,thermal gravimetric analysis and nanoindentation.The structural transformation of single phase cubic Cr_(0.42)Al_(0.58)N and Cr_(0.39)Al_(0.56)Y_(0.05)N coatings to cubic−wurtzite mixed Cr_(0.32)Al_(0.56)Y_(0.12)N coating leads to a drop in hardness from(30.2±0.7)GPa of Cr_(0.42)Al_(0.58)N and(32.0±1.0)GPa of Cr_(0.39)Al_(0.56)Y_(0.05)N to(25.2±0.7)GPa of Cr_(0.32)Al_(0.56)Y_(0.12)N.The incorporation of 5 at.%Y retards the thermal decomposition of CrAlN,verified by the postponed precipitation of w-AlN and N-loss upon annealing.Correspondingly,Cr_(0.39)Al_(0.56)Y_(0.05)N coating consistently exhibits the highest hardness value during thermal annealing.Nevertheless,alloying with Y exerts an adverse effect on the oxidation resistance of CrAlN.展开更多
N6-methyladenosine(m^(6)A)plays an important role in embryogenesis,nuclear export,transcription splicing,and protein translation control.Herein,we demonstrate a copper-free click chemistry-mediated assembly of single ...N6-methyladenosine(m^(6)A)plays an important role in embryogenesis,nuclear export,transcription splicing,and protein translation control.Herein,we demonstrate a copper-free click chemistry-mediated assembly of single quantum dot(QD)nanosensor for accurately monitoring locus-specific m^(6)A in cancer cells.The m^(6)A-sensitive endoribonuclease MazF can digest the unmethylated A-RNA,and the intact m^(6)A-RNA then hybridizes with DNA probes a and b to produce a sandwich hybrid,initiating the click chemistry to generate probe a–b ligation product via first tandem ligation detection reaction(LDR)cycle.Subsequently,DNA probes c and d can hybridize with the probe a–b ligation product to generate the probe c–d ligation product via second LDR cycle.Both LDR cycles can be repeated through denaturation and annealing reaction to generate abundant biotin-/fluorophore-modified probe c–d ligation products that can easily assemble on the QD surface to induce distinct fluorescence resonance energy transfer(FRET)between QD and Cy5.This assay can be homogenously performed without the involvement of copper catalyst,m^(6)A-specific antibody,radioactive labeling,ligase enzyme,enzymatic reverse transcription,and next-generation sequencing.Moreover,it can discriminate even 0.01% m^(6)A level in complex samples and accurately measure cellular m^(6)A-RNA expression,providing a promising avenue for clinical diagnostics and biomedical research.展开更多
Background There is tremendous increase in obesity worldwide.Many factors including diet,life style,genetic,and epigenetic changes contribute to obesity.The fat mass and obesity-associated (FTO) gene polymorphisms are...Background There is tremendous increase in obesity worldwide.Many factors including diet,life style,genetic,and epigenetic changes contribute to obesity.The fat mass and obesity-associated (FTO) gene polymorphisms are strongly associated with obesity.It has been reported that FTO single-nucleotide polymorphisms (SNPs) are associated with obesity in European populations;however,it was controversial in Chinese population.The present meta-analysis study was designed to investigate the association between FTO polymorphisms and obesity risk in Chinese population.Methods The investigators searched studies using the following databases:PubMed,web of science,and Cochrane Central Register of Controlled Trials.A random-effects model was used to calculate the pooled odds ratios (ORs).The heterogeneity among the studies was measured by I2 value.Subgroup analysis was used to find out the potential factors influencing the heterogeneity.Results A total of 18 articles including 26 studies were included in the present meta-analysis.Overall,the FTO SNPs were significantly associated with obesity in Chinese population (OR 1.30;95% CI 1.19-1.42;P < 0.001) under per-allele comparison.The subgroup analysis also showed strong association between four FTO SNPs (rs9939609,rs6499640,rs8050136,and rs 1558902) and obesity risk.Furthermore,subgroup analysis stratified by children/adolescent and adult groups showed same trend.Conclusion The present meta-analysis indicated that FTO SNPs are associated with obesity risk in both children/adolescents and adults in Chinese population.展开更多
文摘Background:The supine position is the most common birth position adopted in China,but the World Health Organization recommends non-supine positions for delivery.The handsand-knees position shows several advantages,such as wide pelvic diameter and easy fetal rotation during delivery.Small trials conducted in China in 2011 revealed that the handsand-knees position resulted in improved maternal and neonate outcomes than those in the supine position.However,a comprehensive study must be conducted before the handsand-knees position can be introduced into clinical practice.Hence,we conducted this multicenter trial to comprehensively examine the benefits of the hands-and-knees position over the supine position during delivery.Methods:Our clinical study was conducted in 11 hospitals in China from May to December 2012.A total of 446 pregnant women who gave birth in the hands-and-knees position were assigned into the experimental group,and 440 women who gave birth in the supine position were classified into the control group.Episiotomy rate was evaluated as the primary outcome,and perineum laceration degree was considered the secondary outcome.Results:Women in the experimental group achieved lower rates of episiotomy and higher rates of intact perineum and first-degree perineum lacerations compared with those in the control.Postpartum bleeding amount,neonatal asphyxia,and APGAR scores at 1 and 5 min were not significantly different between the two groups.Conclusions:This study proves that women who delivered in the hands-and-knees position achieved low rates of episiotomy and intact perineum.Moreover,the rates of neonatal asphyxia and postpartum bleeding did not increase.Pregnant patients who prefer to adopt the hands-and-knees position should be assisted in assuming such position during delivery.
基金The authors are grateful for the financial supports from the National Natural Science Foundation of China(No.51775560).
文摘CrAlYN coatings with different Y contents(0,5 and 12 at.%)were deposited by cathodic arc evaporation to investigate the influence of Y-addition on the structure,mechanical and thermal properties of CrAlN coatings by using X-ray diffraction,scanning electron microscopy,differential scanning calorimetry,thermal gravimetric analysis and nanoindentation.The structural transformation of single phase cubic Cr_(0.42)Al_(0.58)N and Cr_(0.39)Al_(0.56)Y_(0.05)N coatings to cubic−wurtzite mixed Cr_(0.32)Al_(0.56)Y_(0.12)N coating leads to a drop in hardness from(30.2±0.7)GPa of Cr_(0.42)Al_(0.58)N and(32.0±1.0)GPa of Cr_(0.39)Al_(0.56)Y_(0.05)N to(25.2±0.7)GPa of Cr_(0.32)Al_(0.56)Y_(0.12)N.The incorporation of 5 at.%Y retards the thermal decomposition of CrAlN,verified by the postponed precipitation of w-AlN and N-loss upon annealing.Correspondingly,Cr_(0.39)Al_(0.56)Y_(0.05)N coating consistently exhibits the highest hardness value during thermal annealing.Nevertheless,alloying with Y exerts an adverse effect on the oxidation resistance of CrAlN.
基金supported by the National Natural Science Foundation of China(Grant No.21735003).
文摘N6-methyladenosine(m^(6)A)plays an important role in embryogenesis,nuclear export,transcription splicing,and protein translation control.Herein,we demonstrate a copper-free click chemistry-mediated assembly of single quantum dot(QD)nanosensor for accurately monitoring locus-specific m^(6)A in cancer cells.The m^(6)A-sensitive endoribonuclease MazF can digest the unmethylated A-RNA,and the intact m^(6)A-RNA then hybridizes with DNA probes a and b to produce a sandwich hybrid,initiating the click chemistry to generate probe a–b ligation product via first tandem ligation detection reaction(LDR)cycle.Subsequently,DNA probes c and d can hybridize with the probe a–b ligation product to generate the probe c–d ligation product via second LDR cycle.Both LDR cycles can be repeated through denaturation and annealing reaction to generate abundant biotin-/fluorophore-modified probe c–d ligation products that can easily assemble on the QD surface to induce distinct fluorescence resonance energy transfer(FRET)between QD and Cy5.This assay can be homogenously performed without the involvement of copper catalyst,m^(6)A-specific antibody,radioactive labeling,ligase enzyme,enzymatic reverse transcription,and next-generation sequencing.Moreover,it can discriminate even 0.01% m^(6)A level in complex samples and accurately measure cellular m^(6)A-RNA expression,providing a promising avenue for clinical diagnostics and biomedical research.
文摘Background There is tremendous increase in obesity worldwide.Many factors including diet,life style,genetic,and epigenetic changes contribute to obesity.The fat mass and obesity-associated (FTO) gene polymorphisms are strongly associated with obesity.It has been reported that FTO single-nucleotide polymorphisms (SNPs) are associated with obesity in European populations;however,it was controversial in Chinese population.The present meta-analysis study was designed to investigate the association between FTO polymorphisms and obesity risk in Chinese population.Methods The investigators searched studies using the following databases:PubMed,web of science,and Cochrane Central Register of Controlled Trials.A random-effects model was used to calculate the pooled odds ratios (ORs).The heterogeneity among the studies was measured by I2 value.Subgroup analysis was used to find out the potential factors influencing the heterogeneity.Results A total of 18 articles including 26 studies were included in the present meta-analysis.Overall,the FTO SNPs were significantly associated with obesity in Chinese population (OR 1.30;95% CI 1.19-1.42;P < 0.001) under per-allele comparison.The subgroup analysis also showed strong association between four FTO SNPs (rs9939609,rs6499640,rs8050136,and rs 1558902) and obesity risk.Furthermore,subgroup analysis stratified by children/adolescent and adult groups showed same trend.Conclusion The present meta-analysis indicated that FTO SNPs are associated with obesity risk in both children/adolescents and adults in Chinese population.