Background The International Association of Diabetes and Pregnancy Study Group （IADPSG） recommended new diagnostic criteria for gestational diabetes mellitus （GDM） after extensive analyses of the Hyperglycemia and...Background The International Association of Diabetes and Pregnancy Study Group （IADPSG） recommended new diagnostic criteria for gestational diabetes mellitus （GDM） after extensive analyses of the Hyperglycemia and Adverse Pregnancy Outcomes （HAPO） study. Unfortunately, there was no data from mainland of China in this study. We evaluated the feasibility of IADPSG criteria for GDM diagnosis in China. Methods A large prospective study was conducted. We reviewed medical records of a total of 25 674 pregnant women who underwent GDM screening and diagnosis between January 1, 2005 and December 31, 2012 in the Peking University First Hospital. The prevalence of gestational glucose metabolism abnormalities was calculated according to different cut off values defined by the National Diabetes Data Group （NDDG） or the IADPSG, and the incidence of adverse pregnancy outcomes related to GDM was analyzed. Results According to the cut off values of NDDG and IADPSG criteria, the prevalence of gestational glucose metabolism abnormalities was 8.4% and 18.9% （P 〈0.01） respectively, and the prevalence of cesarean section （52.5% vs. 46.0%, P 〈0.01）, macrosomia （7.5% vs. 6.3%, P 〈0.05）, neonatal hypoglycemia （1.6% vs. 1.0%, P 〈0.01）, and perinatal death （0.5% vs. 0.2%, P 〈0.01）; the prevalence was significantly lower when IADPSG criteria were applied. The prevalence of macrosomia, cesarean section, neonatal hypoglycemia, pregnancy induced hypertension, etc. was also higher in the GDM group than in the normal group. The prevalence of cesarean section （62.3%） and macrosomia （14.8%） was the highest in untreated mild GDM patients. Conclusions Our results indicated that treatment/intervention of women with GDM identified by IADPSG criteria was related to significantly lower risk of multiple adverse pregnancy outcomes. Such findings provide support for applying IADPSG criteria in China.展开更多
This paper analyzes the monitored data of the 4 times of stream water conveyances to the river section where the stream flow was cut-off, of 9 groundwater-monitoring sections and 18 vegetation plots in the lower reach...This paper analyzes the monitored data of the 4 times of stream water conveyances to the river section where the stream flow was cut-off, of 9 groundwater-monitoring sections and 18 vegetation plots in the lower reaches of Tarim River. The results show that the groundwater depth in the lower reaches of Tarim River rose from 9.87 m before the conveyances to 7.74 m and 3.79 m after the first and second conveyances, 3.61 and 3.16 m after the 2 phases of the third conveyance, and 2.66 m after the fourth conveyance. The transverse response scope of groundwater level was gradually enlarged along both sides of the channel of conveyances, i.e., from 450 m in width after the first conveyance to 1050 m after the fourth conveyance, but the response degree of groundwater level was reduced with the increase of the distance away from the channel of conveyances. The composition, distribution and growth status of the natural vegetation are directly related to the groundwater depth. The indexes of Simpson’s biodiversity, McIntosh’s evenness and Margalef’s richness, which reflect the change of the quantity of species and the degree of biodiversity, are reduced from 0.70, 0.48 and 0.90 to 0.26, 0.17 and 0.37 re- spectively along with the drawdown of groundwater level from the upper reaches to the lower reaches. After the stream water conveyances, the natural vegetation in the lower reaches is saved and restored along with the rise of groundwater level, the response scope of vegetation is gradually enlarged, i.e., from 200— 250 m in width after the first conveyance to 800 m after the fourth conveyance. However, there is still a great disparity to the objective of protecting the “Green Corridor”in the lower reaches of Tarim River. Thus, it is suggested to convey the stream water in double-channel way, combine the conveyance with water supply in surface scope, or construct the modern pipe-conveyance network systems so as to save the natural vegetation in an intensive way, achieve the efficient water consumption and speed u展开更多
随着剖宫产率的逐年上升，有剖宫产史的孕妇也日益增多，有剖宫产史孕妇再次妊娠分娩问题及相应并发症的出现逐渐成为我国产科临床面临的常见问题。1916年，Cragin提出“1次剖宫产，次次剖宫产的说法”（once a cesarean，always a cesa...随着剖宫产率的逐年上升，有剖宫产史的孕妇也日益增多，有剖宫产史孕妇再次妊娠分娩问题及相应并发症的出现逐渐成为我国产科临床面临的常见问题。1916年，Cragin提出“1次剖宫产，次次剖宫产的说法”（once a cesarean，always a cesarean）。1980年，美国提出剖宫产术后阴道试产（trialoflabor，TOL）的概念，此后开展了大量的关于剖宫产术后阴道分娩（vaginal birth after cesarean section，VBAC）的研究。展开更多
Background：In the mainland of China, the trial of labor after cesarean section is still a relatively new technique. In this study, we aimed to investigate the effects of labor onset, oxytocin use, and epidural anesth...Background：In the mainland of China, the trial of labor after cesarean section is still a relatively new technique. In this study, we aimed to investigate the effects of labor onset, oxytocin use, and epidural anesthesia on maternal and neonatal outcomes for vaginal birth after cesarean section （VBAC） in a tertiary hospital in China.Methods：This was a retrospective study carried out on 212 VBAC cases between January 2015 and June 2017 in Beijing Obstetrics and Gynecology Hospital, Capital Medical University. Relevant data were acquired on a form, including maternal age, gravidity and parity, body mass index before pregnancy, weight gain during pregnancy, type of labor onset, gestational age, the use of oxytocin and epidural anesthesia, birth mode, the duration of labor, and neonatal weight. The factors affecting maternal and neonatal outcomes for cases involving VBAC, especially with regards to postpartum hemorrhage （PPH） and fetal distress, were evaluated by univariate analysis and multivariable logistic regression.Results：Data showed that 36 women （17.0%） had postpartum hemorrhage （PPH） and 51 cases （24.1%） featured fetal distress. Normal delivery took place for 163 infants （76.9%） while 49 infants （23.1%） underwent operative vaginal deliveries with forceps. There were 178 cases （84.0%） of spontaneous labor and 34 cases （16.0%） required induction. Oxytocin was used in 54 cases （25.5%） to strengthen uterine contraction, and 65 cases （30.7%） received epidural anesthesia. The rate of normal delivery in cases involving PPH was significantly lower than those without PPH （61.1% vs. 80.1%; χ2 = 6.07, P = 0.01）. Multivariate logistic analysis showed that the intrapartum administration of oxytocin （odds ratio [OR] = 2.47; 95% confidence interval [CI] = 1.07–5.74; P = 0.04） and birth mode （OR = 0.40; 95% CI = 0.18–0.87; P = 0.02） was significantly associated with PPH in VBAC cases. Operative vaginal delivery occurred more frequently in the group with feta展开更多
Both gradual and sharp decrease in organic and carbonate carbon isotope values were detected across the Permian-Triassic boundary in the Meishan section, Changxing, Zhejiang Province, China. The gradual decrease in or...Both gradual and sharp decrease in organic and carbonate carbon isotope values were detected across the Permian-Triassic boundary in the Meishan section, Changxing, Zhejiang Province, China. The gradual decrease in organic carbon isotope values started at the bottom of Bed 23, coinciding with the strong oscillations of total organic carbon (TOC) contents, indicates increasing fluxes from carbonate to organic carbon reservoir during this interval. A 2.3‰ sharp drop of inorganic carbon isotope values occurred at the uppermost part of Bed 24e. A 3.7‰ sharp drop of organic carbon isotope values occurred in Bed 26. The dramatic drop of inorganic carbon isotope value of 8‰ reported previously is not confirmed from the unweathered carbonate samples in Bed 27. The large-scale fluctuation of organic carbon isotope values in the Yinkeng Formation reflects different extent of mixing of marine and terrestrial organic matters. The gradual depletion and subsequent sharp drop of carbon isotopes near the展开更多
Background： After the two-child policy is frilly implemented, new challenges regarding pregnancy management and the treatment of pregnancy complications will arise. The aim of this study was to analyze the characteri...Background： After the two-child policy is frilly implemented, new challenges regarding pregnancy management and the treatment of pregnancy complications will arise. The aim of this study was to analyze the characteristics of pregnancy and delivery before and after the implementation of the two-child policy to make suggestions on the quality assurance of the new era of obstetrics. Methods： In total, 5895 cases of pregnant women who delivered from April 2016 to March 2017 in Peking University Third Hospital served as the study group and 5103 cases of pregnant women who delivered from January to December 2015 served as the control group. The characteristics of pregnancy and delivery were retrospectively analyzed. Results： In the study group, the percentage of pregnant women who were older （over 40 years） （3.6% vs. 2.2%）, were multipara （30.3% vs. 17.0%）, received irregular prenatal care （ 1.5% vs. 0.9%）, were transferred for treatment from a subordinate hospital （4.4% vs. 2.8%）, and were not residents of Beijing （3.8% vs. 2.2%）, were significantly increased compared with the control group （P 〈 0.05）. In the study group, the rate of a hypertensive disorder complicating pregnancy （6.4% vs. 5.0%）, gestational diabetes mellitus （25.3% vs. 23.1%）, dangerous placenta previa （3.0% vs. 2.3%）, placental implantation （2.4% vs. 1.8%）, and severe postpartum hemorrhage （2.8% vs. 1.9%） was significantly increased compared with the control group （P 〈 0.05）. In the study group, the cesarean section rate during primipara was significantly reduced compared with the control group （42.0% vs. 44.2%）. However, the rate during inultipara was significantly increased compared with the control group （P 〈 0.05）. Indications for cesarean section in the study group as well as the percentages of scared uterus and placenta previa were significantly increased compared with the control group （P 〈 0.05）. Conclusions： According to the current situation, better methods are展开更多
In this paper,a new GLKKM type theorem is established for noncompact complete L-convex metric spaces.As applications,the properties of the solution set of variational in-equalities,intersection point sets,Ky Fan secti...In this paper,a new GLKKM type theorem is established for noncompact complete L-convex metric spaces.As applications,the properties of the solution set of variational in-equalities,intersection point sets,Ky Fan sections and maximal element sets are shown,and a Fan-Browder fixed point theorem is obtained.展开更多
Three-dimensional geological modeling （3DGM） assists geologists to quantitatively study in three-dimensional （3D） space structures that define temporal and spatial relationships between geological objects. The 3D ...Three-dimensional geological modeling （3DGM） assists geologists to quantitatively study in three-dimensional （3D） space structures that define temporal and spatial relationships between geological objects. The 3D property model can also be used to infer or deduce causes of geological objects. 3DGM technology provides technical support for extraction of diverse geoscience information, 3D modeling, and quantitative calculation of mineral resources. Based on metallogenic concepts and an ore deposit model, 3DGM technology is applied to analyze geological characteristics of the Tongshan Cu deposit in order to define a metallogenic model and develop a virtual borehole technology; a BP neural network and a 3D interpolation technique were combined to integrate multiple geoscience information in a 3D environment. The results indicate： （1） on basis of the concept of magmatic-hydrothermal Cu polymetallic mineraliza- tion and a porphyry Cu deposit model, a spatial relational database of multiple geoscience information for mineralization in the study area （geology, geophysics, geochemistry, borehole, and cross-section data） was established, and 3D metallogenic geological objects including mineralization stratum, granodiorite, alteration rock, and magnetic anomaly were constructed; （2） on basis of the 3D ore deposit model, 23,800 effective surveys from 94 boreholes and 21 sections were applied to establish 3D orebody models with a kriging interpolation method; （3） combined 23,800 surveys involving 21 sections, using VC＋＋ and OpenGL platform, virtual borehole and virtual section with BP network, and an improved inverse distance interpolation （IDW） method were used to predict and delineate mineralization potential targets （Cu-grade of cell not less than 0.1%）; （4） comparison of 3D ore bodies, metallogenic geological objects of mineralization, and potential targets of mineralization models in the study area, delineated the 3D spatial and temporal relationship and causal processes among th展开更多
Determination of the age of the Precambrian-Cambrian boundary is critical in understanding early evolution of life on Earth. SIMS U-Pb zircon analyses of the Bed 5 tuff layer of the Meishucun section were carried out ...Determination of the age of the Precambrian-Cambrian boundary is critical in understanding early evolution of life on Earth. SIMS U-Pb zircon analyses of the Bed 5 tuff layer of the Meishucun section were carried out closely following the guidance of cath展开更多
文摘Background The International Association of Diabetes and Pregnancy Study Group （IADPSG） recommended new diagnostic criteria for gestational diabetes mellitus （GDM） after extensive analyses of the Hyperglycemia and Adverse Pregnancy Outcomes （HAPO） study. Unfortunately, there was no data from mainland of China in this study. We evaluated the feasibility of IADPSG criteria for GDM diagnosis in China. Methods A large prospective study was conducted. We reviewed medical records of a total of 25 674 pregnant women who underwent GDM screening and diagnosis between January 1, 2005 and December 31, 2012 in the Peking University First Hospital. The prevalence of gestational glucose metabolism abnormalities was calculated according to different cut off values defined by the National Diabetes Data Group （NDDG） or the IADPSG, and the incidence of adverse pregnancy outcomes related to GDM was analyzed. Results According to the cut off values of NDDG and IADPSG criteria, the prevalence of gestational glucose metabolism abnormalities was 8.4% and 18.9% （P 〈0.01） respectively, and the prevalence of cesarean section （52.5% vs. 46.0%, P 〈0.01）, macrosomia （7.5% vs. 6.3%, P 〈0.05）, neonatal hypoglycemia （1.6% vs. 1.0%, P 〈0.01）, and perinatal death （0.5% vs. 0.2%, P 〈0.01）; the prevalence was significantly lower when IADPSG criteria were applied. The prevalence of macrosomia, cesarean section, neonatal hypoglycemia, pregnancy induced hypertension, etc. was also higher in the GDM group than in the normal group. The prevalence of cesarean section （62.3%） and macrosomia （14.8%） was the highest in untreated mild GDM patients. Conclusions Our results indicated that treatment/intervention of women with GDM identified by IADPSG criteria was related to significantly lower risk of multiple adverse pregnancy outcomes. Such findings provide support for applying IADPSG criteria in China.
基金supported by the National Natural Science Foundation of China(Grant No.90102007)the Knowledge Innovation Project of the Chinese Academy of Sciences(Grant No.KZCX1-08-03).
文摘This paper analyzes the monitored data of the 4 times of stream water conveyances to the river section where the stream flow was cut-off, of 9 groundwater-monitoring sections and 18 vegetation plots in the lower reaches of Tarim River. The results show that the groundwater depth in the lower reaches of Tarim River rose from 9.87 m before the conveyances to 7.74 m and 3.79 m after the first and second conveyances, 3.61 and 3.16 m after the 2 phases of the third conveyance, and 2.66 m after the fourth conveyance. The transverse response scope of groundwater level was gradually enlarged along both sides of the channel of conveyances, i.e., from 450 m in width after the first conveyance to 1050 m after the fourth conveyance, but the response degree of groundwater level was reduced with the increase of the distance away from the channel of conveyances. The composition, distribution and growth status of the natural vegetation are directly related to the groundwater depth. The indexes of Simpson’s biodiversity, McIntosh’s evenness and Margalef’s richness, which reflect the change of the quantity of species and the degree of biodiversity, are reduced from 0.70, 0.48 and 0.90 to 0.26, 0.17 and 0.37 re- spectively along with the drawdown of groundwater level from the upper reaches to the lower reaches. After the stream water conveyances, the natural vegetation in the lower reaches is saved and restored along with the rise of groundwater level, the response scope of vegetation is gradually enlarged, i.e., from 200— 250 m in width after the first conveyance to 800 m after the fourth conveyance. However, there is still a great disparity to the objective of protecting the “Green Corridor”in the lower reaches of Tarim River. Thus, it is suggested to convey the stream water in double-channel way, combine the conveyance with water supply in surface scope, or construct the modern pipe-conveyance network systems so as to save the natural vegetation in an intensive way, achieve the efficient water consumption and speed u
文摘随着剖宫产率的逐年上升，有剖宫产史的孕妇也日益增多，有剖宫产史孕妇再次妊娠分娩问题及相应并发症的出现逐渐成为我国产科临床面临的常见问题。1916年，Cragin提出“1次剖宫产，次次剖宫产的说法”（once a cesarean，always a cesarean）。1980年，美国提出剖宫产术后阴道试产（trialoflabor，TOL）的概念，此后开展了大量的关于剖宫产术后阴道分娩（vaginal birth after cesarean section，VBAC）的研究。
文摘Background：In the mainland of China, the trial of labor after cesarean section is still a relatively new technique. In this study, we aimed to investigate the effects of labor onset, oxytocin use, and epidural anesthesia on maternal and neonatal outcomes for vaginal birth after cesarean section （VBAC） in a tertiary hospital in China.Methods：This was a retrospective study carried out on 212 VBAC cases between January 2015 and June 2017 in Beijing Obstetrics and Gynecology Hospital, Capital Medical University. Relevant data were acquired on a form, including maternal age, gravidity and parity, body mass index before pregnancy, weight gain during pregnancy, type of labor onset, gestational age, the use of oxytocin and epidural anesthesia, birth mode, the duration of labor, and neonatal weight. The factors affecting maternal and neonatal outcomes for cases involving VBAC, especially with regards to postpartum hemorrhage （PPH） and fetal distress, were evaluated by univariate analysis and multivariable logistic regression.Results：Data showed that 36 women （17.0%） had postpartum hemorrhage （PPH） and 51 cases （24.1%） featured fetal distress. Normal delivery took place for 163 infants （76.9%） while 49 infants （23.1%） underwent operative vaginal deliveries with forceps. There were 178 cases （84.0%） of spontaneous labor and 34 cases （16.0%） required induction. Oxytocin was used in 54 cases （25.5%） to strengthen uterine contraction, and 65 cases （30.7%） received epidural anesthesia. The rate of normal delivery in cases involving PPH was significantly lower than those without PPH （61.1% vs. 80.1%; χ2 = 6.07, P = 0.01）. Multivariate logistic analysis showed that the intrapartum administration of oxytocin （odds ratio [OR] = 2.47; 95% confidence interval [CI] = 1.07–5.74; P = 0.04） and birth mode （OR = 0.40; 95% CI = 0.18–0.87; P = 0.02） was significantly associated with PPH in VBAC cases. Operative vaginal delivery occurred more frequently in the group with feta
基金This work was supported by the Major Basic Research Projects of the Ministry of Science Technology of China (Grant No. G2000077700) Opening Laboratory of Palaeobiology and Stratigraphy of Nanjing Institute of Geology and Palaeontology, the Chinese
文摘Both gradual and sharp decrease in organic and carbonate carbon isotope values were detected across the Permian-Triassic boundary in the Meishan section, Changxing, Zhejiang Province, China. The gradual decrease in organic carbon isotope values started at the bottom of Bed 23, coinciding with the strong oscillations of total organic carbon (TOC) contents, indicates increasing fluxes from carbonate to organic carbon reservoir during this interval. A 2.3‰ sharp drop of inorganic carbon isotope values occurred at the uppermost part of Bed 24e. A 3.7‰ sharp drop of organic carbon isotope values occurred in Bed 26. The dramatic drop of inorganic carbon isotope value of 8‰ reported previously is not confirmed from the unweathered carbonate samples in Bed 27. The large-scale fluctuation of organic carbon isotope values in the Yinkeng Formation reflects different extent of mixing of marine and terrestrial organic matters. The gradual depletion and subsequent sharp drop of carbon isotopes near the
文摘Background： After the two-child policy is frilly implemented, new challenges regarding pregnancy management and the treatment of pregnancy complications will arise. The aim of this study was to analyze the characteristics of pregnancy and delivery before and after the implementation of the two-child policy to make suggestions on the quality assurance of the new era of obstetrics. Methods： In total, 5895 cases of pregnant women who delivered from April 2016 to March 2017 in Peking University Third Hospital served as the study group and 5103 cases of pregnant women who delivered from January to December 2015 served as the control group. The characteristics of pregnancy and delivery were retrospectively analyzed. Results： In the study group, the percentage of pregnant women who were older （over 40 years） （3.6% vs. 2.2%）, were multipara （30.3% vs. 17.0%）, received irregular prenatal care （ 1.5% vs. 0.9%）, were transferred for treatment from a subordinate hospital （4.4% vs. 2.8%）, and were not residents of Beijing （3.8% vs. 2.2%）, were significantly increased compared with the control group （P 〈 0.05）. In the study group, the rate of a hypertensive disorder complicating pregnancy （6.4% vs. 5.0%）, gestational diabetes mellitus （25.3% vs. 23.1%）, dangerous placenta previa （3.0% vs. 2.3%）, placental implantation （2.4% vs. 1.8%）, and severe postpartum hemorrhage （2.8% vs. 1.9%） was significantly increased compared with the control group （P 〈 0.05）. In the study group, the cesarean section rate during primipara was significantly reduced compared with the control group （42.0% vs. 44.2%）. However, the rate during inultipara was significantly increased compared with the control group （P 〈 0.05）. Indications for cesarean section in the study group as well as the percentages of scared uterus and placenta previa were significantly increased compared with the control group （P 〈 0.05）. Conclusions： According to the current situation, better methods are
基金Foundation item： the Natural Science Research Foundation of Guizhou Provincial Education Department （No. 2008072） the Natural Science Foundation of Science and Technologe Bureau of Bijie Area （No. 2008-06）.
文摘In this paper,a new GLKKM type theorem is established for noncompact complete L-convex metric spaces.As applications,the properties of the solution set of variational in-equalities,intersection point sets,Ky Fan sections and maximal element sets are shown,and a Fan-Browder fixed point theorem is obtained.
基金supported by the National Basic Research Program of China(Grant No.1212010881001 )the National Scicnce of the 12th "Five-Year Technology Support Program"(Grant No.2010BAE00281-6)+1 种基金the National Natural Science Foundation of China(Grant Nos.40772157,40972232, 41072070)the State Key Laboratory of Geological Processes and Mineral Resources(Grant Nos.GPMR0941,200624)
文摘Three-dimensional geological modeling （3DGM） assists geologists to quantitatively study in three-dimensional （3D） space structures that define temporal and spatial relationships between geological objects. The 3D property model can also be used to infer or deduce causes of geological objects. 3DGM technology provides technical support for extraction of diverse geoscience information, 3D modeling, and quantitative calculation of mineral resources. Based on metallogenic concepts and an ore deposit model, 3DGM technology is applied to analyze geological characteristics of the Tongshan Cu deposit in order to define a metallogenic model and develop a virtual borehole technology; a BP neural network and a 3D interpolation technique were combined to integrate multiple geoscience information in a 3D environment. The results indicate： （1） on basis of the concept of magmatic-hydrothermal Cu polymetallic mineraliza- tion and a porphyry Cu deposit model, a spatial relational database of multiple geoscience information for mineralization in the study area （geology, geophysics, geochemistry, borehole, and cross-section data） was established, and 3D metallogenic geological objects including mineralization stratum, granodiorite, alteration rock, and magnetic anomaly were constructed; （2） on basis of the 3D ore deposit model, 23,800 effective surveys from 94 boreholes and 21 sections were applied to establish 3D orebody models with a kriging interpolation method; （3） combined 23,800 surveys involving 21 sections, using VC＋＋ and OpenGL platform, virtual borehole and virtual section with BP network, and an improved inverse distance interpolation （IDW） method were used to predict and delineate mineralization potential targets （Cu-grade of cell not less than 0.1%）; （4） comparison of 3D ore bodies, metallogenic geological objects of mineralization, and potential targets of mineralization models in the study area, delineated the 3D spatial and temporal relationship and causal processes among th
基金Supported by National Natural Science Foundation of China (Grant Nos. 40730211 and 40821091)
文摘Determination of the age of the Precambrian-Cambrian boundary is critical in understanding early evolution of life on Earth. SIMS U-Pb zircon analyses of the Bed 5 tuff layer of the Meishucun section were carried out closely following the guidance of cath
