Background： Gestational diabetes mellitus （GDM） is associated with both short- and long-term adverse health consequences for both the mother and her offspring. The aim was to study the prevalence and risk factors f...Background： Gestational diabetes mellitus （GDM） is associated with both short- and long-term adverse health consequences for both the mother and her offspring. The aim was to study the prevalence and risk factors for GDM in Beijing. Methods： The study population consisted of 15,194 pregnant women attending prenatal care in 15 hospitals in Beijing, who delivered between June 20, 2013, and November 30, 2013, after 28 weeks of gestation. The participants were selected by cluster sampling from the 15 hospitals identified through random systematic sampling based on the number of deliveries in 2012. A questionnaire was designed to collect information. Results： A total of 2987 （19.7%） women were diagnosed with GDM and 208 （1.4%） had diabetes in pregnancy （DIP）, Age （OR： 1.053, 95% CI： 1.033-1.074, P 〈 0.01）, family history of diabetes mellitus （OR： 1.481, 95% CI：1.254 1.748, P 〈 0.01）, prepregnancy body mass index （BMI） （OR： 1.481, 95% CI：1.254 1.748, P 〈 0.01）, BMI gain before 24 weeks （OR： 1.126, 95% CI： 1.075-1.800, P 〈 0.01 ）, maternal birth weight （P 〈 0.01）, and fasting plasma glucose at the first prenatal visit （P 〈 0.01） were identified as risk factors for GDM. In women with birth weight 〈3000 g, GDM rate was significantly higher. Conclusions： One out of every five pregnant women in Beijing either had GDM or DIP and this constitutes a huge health burden for health services. Prepregnancy BMI and weight gain before 24^th week are important modifiable risk factors for GDM. Ensuring birth weight above 3000 g may help reduce risk for future GDM among female offsprings.展开更多
Background： With the progress ofperinatal medicine and neonatal technology, more and more extremely low birth weight （ELBW） survived all over the world. This study was designed to investigate the short-term ontcome...Background： With the progress ofperinatal medicine and neonatal technology, more and more extremely low birth weight （ELBW） survived all over the world. This study was designed to investigate the short-term ontcomes of ELBW infants during their Neonatal Intensive Care Unit （NICU） stay in the mainland of China. Methods： All infants admitted to 26 NICUs with a birth weight （BW） 〈1000 g were included between January 1,2011 and December 31,2011. All the data were collected retrospectively from clinical records by a prospectively designed questionnaire. The data collected from each NICU transmitted to the main institution where the results were aggregated and analyzed. Categorical variables were performed with Pearson Chi-square test. Binary Logistic regression analysis was used to detect risk factors. Results： A total of 258 ELBW infants were admitted to 26 NICUs, of whom the mean gestational age （GA） was 28.1 ± 2.2 weeks, and the mean BW was 868 ± 97 g. The overall survival rate at discharge was 50.0%. Despite aggressive treatment 60 infants （23.3%） died and another 69 infants （26.7%） died after medical care withdrawal. Furthermore, the survival rate was significantly higher in coastal areas than inland areas （53.6% vs. 35.3%, P = 0.019）. BW 〈750 g and GA 〈28 weeks were the largest risk factors, and being small for gestational age was a protective factor related to mortality. Respiratory distress syndrome was the most common complication. The incidence of patent ductus arteriosus, intraventricular hemorrhage, periventricular leukomalacia, bronchopulmonary dysplasia, retinopathy of prematurity was 26.2%, 33.7%, 6.7%, 48.1%, and 41.4%, respectively. Ventilator associated pneumonia was the most common hospital acquired infection during hospitalization. Conclusions： Our study was the first survey that revealed the present status of ELBW infants in the mainland of China. The mortality and morbidity of ELBW infants remained high as compared to other developed countries.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
This is a retrospective,observational study to evaluate the effect of maternal age on the outcomes of in vitro fertilization and embryo transfer(IVF-ET).11830 IVF-ET cycles from 10268 women were included.Four groups o...This is a retrospective,observational study to evaluate the effect of maternal age on the outcomes of in vitro fertilization and embryo transfer(IVF-ET).11830 IVF-ET cycles from 10268 women were included.Four groups of different maternal age periods were compared.The groups were 21 30 years old group(4549 cycles),31-35 years old group(4424 cycles),36-40 years old group(2429 cycles),and over 40 years old group(428 cycles).The mean starting dose of Gn and mean total dose of Gn in each cycle were significantly higher(P<0.01),while the mean retrieved oocyte number was significantly lower(P<0.01) in groups of higher maternal age period than those in each of the lower groups.The biochemical pregnancy rate and the clinical pregnancy rate were significantly lower(P<0.01),while the miscarriage rate was significantly higher(P<0.01) in groups of higher maternal age period than those in the lower groups.No difference was found in two-pronuclear zygotes(2PN) rate and good quality embryo rate among different groups.Birth defect rate was also comparable in the born babies in different groups.In the group with patients' age over 40 years old,the pregnancy rate was 26.87%,the clinical pregnancy rate was 19.39%,while the miscarriage rate after clinical pregnancy was 36.14%.To draw the conclusion,patients with higher maternal age had worse IVF outcomes.In women of fertile age,patients between 20 and 30 years old have the best IVF outcomes.Patients over 40 years old have poor IVF outcome and high miscarriage rate,which suggested the necessity of preimplantation genetic screening(PGS).展开更多
China recently instituted a two-child policy in response to its aging population, declining workforce and demographic dividend, and the need to develop asocial economy. Additionally, women generally delay having a sec...China recently instituted a two-child policy in response to its aging population, declining workforce and demographic dividend, and the need to develop asocial economy. Additionally, women generally delay having a second child because of the overwhelming pressure in their lives. With the improvements in assisted fertility technologies in recent years, the number of elderly women attempting to bear children has increased. The quality of woman＇s eggs and a man＇s sperm declined dramatically with increasing age, leading to an increased risk of pregnancy-related complications among older women. Therefore, the types of fertility problems experienced by elderly females must be provided with considerable attention by obstetricians. This commentary article focuses on the medical problems faced by older second-child pregnant women. This work discusses their increased rates of infertility, spontaneous abortion, fetal malformation, gestational diabetes, cesarean section, placenta previa, postpartum hemorrhage, postpartum depression, and hypertensive disorders, which complicate pregnancy.展开更多
Objective To explore the etiology, incidence and methods to prevent and treat severe retinopathy of prematurity （ROP）,which is rapidly becoming a threat to the vision of babies in areas of the world where increasing...Objective To explore the etiology, incidence and methods to prevent and treat severe retinopathy of prematurity （ROP）,which is rapidly becoming a threat to the vision of babies in areas of the world where increasing numbers of premature babies are surviving.Data sources The data used in this review were mainly from Medline and PubMed published in English. The search term was ＂retinopathy of prematurity and premature birth＂.Study selection We discuss the historical perspectives, prevalence and incidence, classification and treatment methods of ROP in premature babies.Results Peripheral retinal ablation for eyes with severe ROP can help prevent progression to blindness and several large clinical trials have shown the effectiveness of this treatment in high risk eyes. As a greater proportion of VLBW and ELBW babies survive, the population of babies at risk increases. In various regions of the world, different identification criteria are used to determine which babies are at risk of blindness in order to provide timely diagnostic examinations and treatment as needed. Methods for preventiing ROP include better ante-natal and obstetric care leading to a reduction in the rate of prematurity, the use of ante-natal corticosteroids, and better neonatal care practices. Recent developments have indicated that management of oxygen supplementation is important for the prevention of severe ROP; however,there is not yet known what oxygen saturation target should be adopted. Sepsis increases severe ROP in very preterm infants. Genetic associations and a telemedicine approach may be explored to detect ROP. Treatment of anti-VEGF therapy are potentially useful in eyes with severe ROP, but long term effects are not yet known and such treatment should be used with great caution.Conclusions ROP is a potentially binding disease for premature babies which is becoming more prevalent with the development improving neonatal services in many countries in recent years. High priority should be placed on developing approaches to preven展开更多
Based on a new explicit representation of the solution to the Poisson equation with respect to single birth processes, the unified treatment for various criteria on classical problems （including uniqueness, recurrenc...Based on a new explicit representation of the solution to the Poisson equation with respect to single birth processes, the unified treatment for various criteria on classical problems （including uniqueness, recurrence, ergodicity, exponential ergodicity, strong ergodicity, as well as extinction probability, etc.） for the processes are presented.展开更多
Objective:To observe the effect of curcumin on expressions of nuclear transcription factorkappa Bp65(NF-κBp65),TNF--α and IL-8 in placental tissue of premature birth of infected mice induced by lipopolysaccharide(LP...Objective:To observe the effect of curcumin on expressions of nuclear transcription factorkappa Bp65(NF-κBp65),TNF--α and IL-8 in placental tissue of premature birth of infected mice induced by lipopolysaccharide(LPS).Methods:A total of 60 C57BL/6 mice pregnant with 15 d were collected and randomly divided into control group,model group,treatment group and preventative group.LPS was repeatedly injected in abdominal cavity to construct infected premature birth model,while mice of control group were given with 100 mg/kg of vitamin C through abdominal cavity injection and mice of treatment group and preventative group were given curcumin of 100 mg/kg through abdominal cavity injection after modeling operation and before 1 d of modeling operation,respectively.A total of 5 mice of four groups respectively were executed by cervical dislocation after 6 h,12 h and 24 h after constructing model.Placental tissues were collected and the immunohistochemical mothod SABC of immunologic tissue was used to detect the expression of NF-d mice after 24 h was collected tκBp65,TNF-o detect the co-and IL-8 and peripheral blood of executencentrations of IL-8,malondialdehyde(MDA) and superoxide dismutase(SOD),meanwhile live birth rate of four groups was contrasted.Results:Staining intensity of NF-tissue of treatment group and preventative group was κBp65,TNF-significantly-αand IL-8 in placental higher than control group but lower than model group(P<0.05).Level of serum IL-8 and MDA of control group was significantly lower than the other three groups(P<0.05) and level of blood of SOD in model group was significantly lower than control group(P<0.05).Levels of serum IL-8 and MDA of treatment group and preventative group were significantly lower than model group(P<0.05) while level of SOD was significantly higher than model group(P<0.05).Live birth rate of treatment group and preventative group was significantly higher than model group(P<0.05).Conclusions:Curcumin can effectively prevent the active pathway of NF-t tissue of premature b展开更多
Maternal diabetes constitutes an unfavorable environment for embryonic and fetoplacental development. Despite current treatments, pregnant women with pregestational diabetes are at increased risk for congenital malfor...Maternal diabetes constitutes an unfavorable environment for embryonic and fetoplacental development. Despite current treatments, pregnant women with pregestational diabetes are at increased risk for congenital malformations, materno-fetal complications, placental abnormalities and intrauterine malprogramming. The complications during pregnancy concern the mother (gravidic hypertension and/or preeclampsia, cesarean section) and the fetus (macrosomia or intrauterine growth restriction, shoulder dystocia, hypoglycemia and respiratory distress). The fetoplacental impairment and intrauterine programming of diseases in the offspring's later life induced by gestational diabetes are similar to those induced by type 1 and type 2 diabetes mellitus. Despite the existence of several developmental and morphological differences in the placenta from rodents and women, there are similarities in the alterations induced by maternal diabetes in the placenta from diabetic patients and diabetic experimental models. From both human and rodent diabetic experimentalmodels, it has been suggested that the placenta is a compromised target that largely suffers the impact of maternal diabetes. Depending on the maternal metabolic and proin ammatory derangements, macrosomia is explained by an excessive availability of nutrients and an increase in fetal insulin release, a phenotype related to the programming of glucose intolerance. The degree of fetal damage and placental dysfunction and the availability and utilisation of fetal substrates can lead to the induction of macrosomia or intrauterine growth restriction. In maternal diabetes, both the maternal environment and the genetic background are important in the complex and multifactorial processes that induce damage to the embryo, the placenta, the fetus and the offspring. Nevertheless, further research is needed to better understand the mechanisms that govern the early embryo development, the induction of congenital anomalies and fetal overgrowth in maternal diabetes.展开更多
Objective To investigate the relation between air pollution exposure and preterm birth in Shanghai, China. Methods We examined the effect of ambient air pollution on preterm birth using time-series approach in Shangha...Objective To investigate the relation between air pollution exposure and preterm birth in Shanghai, China. Methods We examined the effect of ambient air pollution on preterm birth using time-series approach in Shanghai in 2004. This method can eliminate potential confounding by individual risk factors that do not change over a short period of time. Daily numbers of preterm births were obtained from the live birth database maintained by Shanghai Municipal Center of Disease Control and Prevention. We used the generalized additive model （GAM） with penalized splines to analyze the relation between preterm birth, air pollution, and covariates. Results We observed a significant effect of outdoor air pollution only with 8-week exposure before preterm births. An increase of 10 μg/m^3 of 8-week average PM10, SO2, NO2, and O3 corresponded to 4.42% （95%CI 1.60%, 7.25%）, 11.89% （95%CI 6.69%, 17.09%）, 5.43% （95%CI 1.78%, 9.08%）, and 4.63% （95%CI 0.35%, 8.91%） increase of preterm birth. We did not find any significant acute effect of outdoor air pollution on preterm birth in the week before birth. Conclusion Ambient air pollution may contribute to the risk of preterm birth in Shanghai. Our analyses also strengthen the rationale for further limiting air pollution level in the city.展开更多
The single birth process is a Markov chain, either time-continuous or time-discrete, valuedin the non-negative integers: the system jumps with positive rate from k to k + 1 but not tok +j for all j 2 (this explains th...The single birth process is a Markov chain, either time-continuous or time-discrete, valuedin the non-negative integers: the system jumps with positive rate from k to k + 1 but not tok +j for all j 2 (this explains the meaning of 'single birth') . However, there is no restrictionfor the jumps from k to k - j(1 j< k). This note mainly deals with the uniqueness problemfor the time-continuous processes with an extension: the jumps from k to k + 1 may also beforbidden for at most finite number of k. In both cases (time-continuous or -discrete), thehitting probability and the first moment of the hitting time are also studied展开更多
Residual stresses can have a strong effect on the usability of machined parts,and the X-ray diffraction(XRD)measuring equipment,which is commonly used to measure residual stresses,is very expensive.This paper presents...Residual stresses can have a strong effect on the usability of machined parts,and the X-ray diffraction(XRD)measuring equipment,which is commonly used to measure residual stresses,is very expensive.This paper presents a method of measuring the residual stresses induced by boring in the internal surface of a tube with much cheaper equipment.The method,called the strain-based method is mainly based on the strains measured on the external surface of the tube.It is proposed on the basis of the very long tube assumption.The finite element method(FEM)analysis is thus used to validate the length of the tube.Guided by the FEM results,an appropriate length of the tube is chosen,and the residual stresses are obtained from both the strain-based method and the XRD method.Stress profiles obtained from both two methods are compared.The comparison result indicates that the profiles of the two methods agree well with each other.Therefore,it can be concluded that the accuracy of the strain-based method is high enough,and it can be applied to residual stress measurement in practice.展开更多
文摘Background： Gestational diabetes mellitus （GDM） is associated with both short- and long-term adverse health consequences for both the mother and her offspring. The aim was to study the prevalence and risk factors for GDM in Beijing. Methods： The study population consisted of 15,194 pregnant women attending prenatal care in 15 hospitals in Beijing, who delivered between June 20, 2013, and November 30, 2013, after 28 weeks of gestation. The participants were selected by cluster sampling from the 15 hospitals identified through random systematic sampling based on the number of deliveries in 2012. A questionnaire was designed to collect information. Results： A total of 2987 （19.7%） women were diagnosed with GDM and 208 （1.4%） had diabetes in pregnancy （DIP）, Age （OR： 1.053, 95% CI： 1.033-1.074, P 〈 0.01）, family history of diabetes mellitus （OR： 1.481, 95% CI：1.254 1.748, P 〈 0.01）, prepregnancy body mass index （BMI） （OR： 1.481, 95% CI：1.254 1.748, P 〈 0.01）, BMI gain before 24 weeks （OR： 1.126, 95% CI： 1.075-1.800, P 〈 0.01 ）, maternal birth weight （P 〈 0.01）, and fasting plasma glucose at the first prenatal visit （P 〈 0.01） were identified as risk factors for GDM. In women with birth weight 〈3000 g, GDM rate was significantly higher. Conclusions： One out of every five pregnant women in Beijing either had GDM or DIP and this constitutes a huge health burden for health services. Prepregnancy BMI and weight gain before 24^th week are important modifiable risk factors for GDM. Ensuring birth weight above 3000 g may help reduce risk for future GDM among female offsprings.
文摘Background： With the progress ofperinatal medicine and neonatal technology, more and more extremely low birth weight （ELBW） survived all over the world. This study was designed to investigate the short-term ontcomes of ELBW infants during their Neonatal Intensive Care Unit （NICU） stay in the mainland of China. Methods： All infants admitted to 26 NICUs with a birth weight （BW） 〈1000 g were included between January 1,2011 and December 31,2011. All the data were collected retrospectively from clinical records by a prospectively designed questionnaire. The data collected from each NICU transmitted to the main institution where the results were aggregated and analyzed. Categorical variables were performed with Pearson Chi-square test. Binary Logistic regression analysis was used to detect risk factors. Results： A total of 258 ELBW infants were admitted to 26 NICUs, of whom the mean gestational age （GA） was 28.1 ± 2.2 weeks, and the mean BW was 868 ± 97 g. The overall survival rate at discharge was 50.0%. Despite aggressive treatment 60 infants （23.3%） died and another 69 infants （26.7%） died after medical care withdrawal. Furthermore, the survival rate was significantly higher in coastal areas than inland areas （53.6% vs. 35.3%, P = 0.019）. BW 〈750 g and GA 〈28 weeks were the largest risk factors, and being small for gestational age was a protective factor related to mortality. Respiratory distress syndrome was the most common complication. The incidence of patent ductus arteriosus, intraventricular hemorrhage, periventricular leukomalacia, bronchopulmonary dysplasia, retinopathy of prematurity was 26.2%, 33.7%, 6.7%, 48.1%, and 41.4%, respectively. Ventilator associated pneumonia was the most common hospital acquired infection during hospitalization. Conclusions： Our study was the first survey that revealed the present status of ELBW infants in the mainland of China. The mortality and morbidity of ELBW infants remained high as compared to other developed countries.
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
文摘This is a retrospective,observational study to evaluate the effect of maternal age on the outcomes of in vitro fertilization and embryo transfer(IVF-ET).11830 IVF-ET cycles from 10268 women were included.Four groups of different maternal age periods were compared.The groups were 21 30 years old group(4549 cycles),31-35 years old group(4424 cycles),36-40 years old group(2429 cycles),and over 40 years old group(428 cycles).The mean starting dose of Gn and mean total dose of Gn in each cycle were significantly higher(P<0.01),while the mean retrieved oocyte number was significantly lower(P<0.01) in groups of higher maternal age period than those in each of the lower groups.The biochemical pregnancy rate and the clinical pregnancy rate were significantly lower(P<0.01),while the miscarriage rate was significantly higher(P<0.01) in groups of higher maternal age period than those in the lower groups.No difference was found in two-pronuclear zygotes(2PN) rate and good quality embryo rate among different groups.Birth defect rate was also comparable in the born babies in different groups.In the group with patients' age over 40 years old,the pregnancy rate was 26.87%,the clinical pregnancy rate was 19.39%,while the miscarriage rate after clinical pregnancy was 36.14%.To draw the conclusion,patients with higher maternal age had worse IVF outcomes.In women of fertile age,patients between 20 and 30 years old have the best IVF outcomes.Patients over 40 years old have poor IVF outcome and high miscarriage rate,which suggested the necessity of preimplantation genetic screening(PGS).
文摘China recently instituted a two-child policy in response to its aging population, declining workforce and demographic dividend, and the need to develop asocial economy. Additionally, women generally delay having a second child because of the overwhelming pressure in their lives. With the improvements in assisted fertility technologies in recent years, the number of elderly women attempting to bear children has increased. The quality of woman＇s eggs and a man＇s sperm declined dramatically with increasing age, leading to an increased risk of pregnancy-related complications among older women. Therefore, the types of fertility problems experienced by elderly females must be provided with considerable attention by obstetricians. This commentary article focuses on the medical problems faced by older second-child pregnant women. This work discusses their increased rates of infertility, spontaneous abortion, fetal malformation, gestational diabetes, cesarean section, placenta previa, postpartum hemorrhage, postpartum depression, and hypertensive disorders, which complicate pregnancy.
文摘Objective To explore the etiology, incidence and methods to prevent and treat severe retinopathy of prematurity （ROP）,which is rapidly becoming a threat to the vision of babies in areas of the world where increasing numbers of premature babies are surviving.Data sources The data used in this review were mainly from Medline and PubMed published in English. The search term was ＂retinopathy of prematurity and premature birth＂.Study selection We discuss the historical perspectives, prevalence and incidence, classification and treatment methods of ROP in premature babies.Results Peripheral retinal ablation for eyes with severe ROP can help prevent progression to blindness and several large clinical trials have shown the effectiveness of this treatment in high risk eyes. As a greater proportion of VLBW and ELBW babies survive, the population of babies at risk increases. In various regions of the world, different identification criteria are used to determine which babies are at risk of blindness in order to provide timely diagnostic examinations and treatment as needed. Methods for preventiing ROP include better ante-natal and obstetric care leading to a reduction in the rate of prematurity, the use of ante-natal corticosteroids, and better neonatal care practices. Recent developments have indicated that management of oxygen supplementation is important for the prevention of severe ROP; however,there is not yet known what oxygen saturation target should be adopted. Sepsis increases severe ROP in very preterm infants. Genetic associations and a telemedicine approach may be explored to detect ROP. Treatment of anti-VEGF therapy are potentially useful in eyes with severe ROP, but long term effects are not yet known and such treatment should be used with great caution.Conclusions ROP is a potentially binding disease for premature babies which is becoming more prevalent with the development improving neonatal services in many countries in recent years. High priority should be placed on developing approaches to preven
基金Acknowledgements This work was supported by the National Natural Science Foundation of China （Grant No. 11131003）, the Specialized Research Fund for the Doctoral Program of Higher Education （No. 20100003110005）, the ＂985＂ project from the Ministry of Education in China, the Fundamental Research Funds for the Central Universities, and the Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions.
文摘Based on a new explicit representation of the solution to the Poisson equation with respect to single birth processes, the unified treatment for various criteria on classical problems （including uniqueness, recurrence, ergodicity, exponential ergodicity, strong ergodicity, as well as extinction probability, etc.） for the processes are presented.
基金supported by Key Science and Technology Program of Education Department of Shaanxi Province(Grant No.11JK06640)
文摘Objective:To observe the effect of curcumin on expressions of nuclear transcription factorkappa Bp65(NF-κBp65),TNF--α and IL-8 in placental tissue of premature birth of infected mice induced by lipopolysaccharide(LPS).Methods:A total of 60 C57BL/6 mice pregnant with 15 d were collected and randomly divided into control group,model group,treatment group and preventative group.LPS was repeatedly injected in abdominal cavity to construct infected premature birth model,while mice of control group were given with 100 mg/kg of vitamin C through abdominal cavity injection and mice of treatment group and preventative group were given curcumin of 100 mg/kg through abdominal cavity injection after modeling operation and before 1 d of modeling operation,respectively.A total of 5 mice of four groups respectively were executed by cervical dislocation after 6 h,12 h and 24 h after constructing model.Placental tissues were collected and the immunohistochemical mothod SABC of immunologic tissue was used to detect the expression of NF-d mice after 24 h was collected tκBp65,TNF-o detect the co-and IL-8 and peripheral blood of executencentrations of IL-8,malondialdehyde(MDA) and superoxide dismutase(SOD),meanwhile live birth rate of four groups was contrasted.Results:Staining intensity of NF-tissue of treatment group and preventative group was κBp65,TNF-significantly-αand IL-8 in placental higher than control group but lower than model group(P<0.05).Level of serum IL-8 and MDA of control group was significantly lower than the other three groups(P<0.05) and level of blood of SOD in model group was significantly lower than control group(P<0.05).Levels of serum IL-8 and MDA of treatment group and preventative group were significantly lower than model group(P<0.05) while level of SOD was significantly higher than model group(P<0.05).Live birth rate of treatment group and preventative group was significantly higher than model group(P<0.05).Conclusions:Curcumin can effectively prevent the active pathway of NF-t tissue of premature b
文摘Maternal diabetes constitutes an unfavorable environment for embryonic and fetoplacental development. Despite current treatments, pregnant women with pregestational diabetes are at increased risk for congenital malformations, materno-fetal complications, placental abnormalities and intrauterine malprogramming. The complications during pregnancy concern the mother (gravidic hypertension and/or preeclampsia, cesarean section) and the fetus (macrosomia or intrauterine growth restriction, shoulder dystocia, hypoglycemia and respiratory distress). The fetoplacental impairment and intrauterine programming of diseases in the offspring's later life induced by gestational diabetes are similar to those induced by type 1 and type 2 diabetes mellitus. Despite the existence of several developmental and morphological differences in the placenta from rodents and women, there are similarities in the alterations induced by maternal diabetes in the placenta from diabetic patients and diabetic experimental models. From both human and rodent diabetic experimentalmodels, it has been suggested that the placenta is a compromised target that largely suffers the impact of maternal diabetes. Depending on the maternal metabolic and proin ammatory derangements, macrosomia is explained by an excessive availability of nutrients and an increase in fetal insulin release, a phenotype related to the programming of glucose intolerance. The degree of fetal damage and placental dysfunction and the availability and utilisation of fetal substrates can lead to the induction of macrosomia or intrauterine growth restriction. In maternal diabetes, both the maternal environment and the genetic background are important in the complex and multifactorial processes that induce damage to the embryo, the placenta, the fetus and the offspring. Nevertheless, further research is needed to better understand the mechanisms that govern the early embryo development, the induction of congenital anomalies and fetal overgrowth in maternal diabetes.
基金The current work was co-funded by China National Science Foundation through grant 30500397 (PI: Y. Zhang)ShanghaiRising-Star Program for Young Investigators through grant 04QMX1402 (PI: H. Kan).
文摘Objective To investigate the relation between air pollution exposure and preterm birth in Shanghai, China. Methods We examined the effect of ambient air pollution on preterm birth using time-series approach in Shanghai in 2004. This method can eliminate potential confounding by individual risk factors that do not change over a short period of time. Daily numbers of preterm births were obtained from the live birth database maintained by Shanghai Municipal Center of Disease Control and Prevention. We used the generalized additive model （GAM） with penalized splines to analyze the relation between preterm birth, air pollution, and covariates. Results We observed a significant effect of outdoor air pollution only with 8-week exposure before preterm births. An increase of 10 μg/m^3 of 8-week average PM10, SO2, NO2, and O3 corresponded to 4.42% （95%CI 1.60%, 7.25%）, 11.89% （95%CI 6.69%, 17.09%）, 5.43% （95%CI 1.78%, 9.08%）, and 4.63% （95%CI 0.35%, 8.91%） increase of preterm birth. We did not find any significant acute effect of outdoor air pollution on preterm birth in the week before birth. Conclusion Ambient air pollution may contribute to the risk of preterm birth in Shanghai. Our analyses also strengthen the rationale for further limiting air pollution level in the city.
文摘The single birth process is a Markov chain, either time-continuous or time-discrete, valuedin the non-negative integers: the system jumps with positive rate from k to k + 1 but not tok +j for all j 2 (this explains the meaning of 'single birth') . However, there is no restrictionfor the jumps from k to k - j(1 j< k). This note mainly deals with the uniqueness problemfor the time-continuous processes with an extension: the jumps from k to k + 1 may also beforbidden for at most finite number of k. In both cases (time-continuous or -discrete), thehitting probability and the first moment of the hitting time are also studied
基金Supported by the National Defense Program of China(C152012C002)the Specialized Research Fund for the Doctoral Program of Higher Education of China(20123218120025)
文摘Residual stresses can have a strong effect on the usability of machined parts,and the X-ray diffraction(XRD)measuring equipment,which is commonly used to measure residual stresses,is very expensive.This paper presents a method of measuring the residual stresses induced by boring in the internal surface of a tube with much cheaper equipment.The method,called the strain-based method is mainly based on the strains measured on the external surface of the tube.It is proposed on the basis of the very long tube assumption.The finite element method(FEM)analysis is thus used to validate the length of the tube.Guided by the FEM results,an appropriate length of the tube is chosen,and the residual stresses are obtained from both the strain-based method and the XRD method.Stress profiles obtained from both two methods are compared.The comparison result indicates that the profiles of the two methods agree well with each other.Therefore,it can be concluded that the accuracy of the strain-based method is high enough,and it can be applied to residual stress measurement in practice.
