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991.
目的 分析异常生育史与遗传性家族史、孕期危险因素暴露的多重对应关系,为进一步完善出生缺陷监测系统和降低出生缺陷发生率提供新的科学依据。方法 对2003至2015年西安市各级开设产科的医疗保健机构分娩的孕28周至生后7 d的围产儿进行出生缺陷监测,并收集相关资料。结果 共监测围产儿1 236 937例,其中出生缺陷患儿10 619例,平均出生缺陷发生率为0.86%(0.70%~1.15%)。多重对应分析显示生育出生缺陷患儿(既往生育1个或2个出生缺陷患儿)与自然流产史、遗传性家族史、有毒有害物质接触史有关,既往生育≥3个出生缺陷患儿与遗传性家族史接近相同区域且距离更近,关系更密切。有自然流产史产妇(257/10 619)再次生育出生缺陷患儿类型依次为先天性心脏病、多指(趾)、神经管缺陷、先天性脑积水、唇裂合并腭裂、单纯唇裂;生育过出生缺陷患儿的产妇(135/10 619)再次生育出生缺陷患儿类型依次为唇裂合并腭裂、无脑畸形、脑积水、神经管缺陷、唇裂、马蹄内翻足。结论 异常生育史与孕期危险因素暴露和遗传性家族史均相关,既往生育≥3个出生缺陷患儿与遗传性家族史关系更密切。 相似文献
992.
Photodynamic therapy (PDT) is a treatment that aims to kill cancer cells by reactive oxygen species, mainly singlet oxygen, produced through light activation of a photosensitiser (PS). Amongst photosensitisers that attracted the most attention in the last decade are cationic and amphiphilic molecules based on porphyrin, chlorin and phthalocyanine structures. Our aim was to join this search for more optimal balance of the lipophilic and hydrophilic moieties in a PS. A new amphiphilic porphyrin, 5-(4-octadecanamidophenyl)-10,15,20-tris(N-methylpyridinium-3-yl)porphyrin trichloride (5) was synthesised and characterised by 1H NMR, UV–vis and fluorescence spectroscopy, and by MALDI-TOF/TOF spectrometry. In vitro photodynamic activity of 5 was evaluated on HeLa cell lines and compared to the activity of the hydrophilic 5-(4-acetamidophenyl)-10,15,20-tris(N-methylpyridinium-3-yl)porphyrin trichloride (7). Low fluence rate (2 mW cm−2) of red light (643 nm) was used for the activation, and both porphyrins showed a drug dose-response as well as a light dose-response relationship, but the amphiphilic porphyrin was presented with significantly lower IC50 values. The obtained IC50 values for 5 were 1.4 μM at 15 min irradiation time and 0.7 μM when the time of irradiation was 30 min, while for 7 these values were 37 and 6 times higher, respectively. These results confirm the importance of the lipophilic component in a PS and show a potential for 5 to be used as a PS in PDT applications. 相似文献
993.
侯文通 《国外畜牧学(草食家畜)》2016,(2):21-29
选择断奶佳米驴、1.5岁驴及当地成年退役驴70头,用传统饲料或全价料加不同粗料肥育,分7个小群,饲喂63 d或113 d。结果表明,63 d日增重1.5岁驴(444.44~560.16)g,成年退役驴(611.11~670.15)g,断奶驴为(185.17~292.86)g;83 d日增重,1.5岁驴(423.42~566.08)g,成年退役驴(493.75~562.00)g。1.5岁驴日增重,以A2全价料加部分苜蓿效果好,与传统料A1群差异极显著(P<0.01),与全价料不加部分苜蓿而加青贮A3群差异显著(P<0.05)。优质肉比例,饲养63 d断奶驹平均为57.03%,饲养113 d,1.5岁佳米驴平均为57.52%,成年退役驴平均为61.92%。1.5岁驴和成年退役驴,屠宰率分别为,43.37%~50.94%,46.64%~50.63%;净肉率分别为34.85%~38.32%,36.03%~36.14%;骨肉比3.19%~4.02%,4.00%~5.45%;脂肉比20.70%~22.65%,4.09%~8.01%。皮厚和皮重,饲养63 d断奶驴分别为(0.60~0.75)cm,(8.27~9.00)kg;肥育113 d 1.5岁佳米驴分别为(0.79~0.99)cm,(9.50~10.33)kg,退役成年驴分别为(0.85~1.04)cm,(10.00~11.60)kg,呈现皮厚随年龄增厚,皮重随年龄营养增重趋势。试驴内脏重量随年龄增大而增加,同龄不同营养群间内脏重量互有高低。试验认为,断奶驴不宜肥育肉用;成年退役驴以63 d强度肥育较好;1.5岁驴可短期(63 d,83 d)强度肥育生产优质驴肉,或肥育数月生产高中档驴肉。 相似文献
994.
目的应用高频定量超声方法比较寒区陆航某部飞行人员不同体位、不同军龄多裂肌收缩功能。方法医务人员携带设备在驻地将飞行人员分为A组(军龄>10年,n=22)与B组(军龄<10年,n=36),在L5平面定量超声测量放松体位、燕飞体位及bird dog体位3种体位的多裂肌厚度及截面积,并进行组间统计学分析。结果 3种体位中,多裂肌收缩最显著的为bird dog体位,其次为燕飞体位。B组多裂肌截面积收缩率明显高于A组(P<0.05);多裂肌厚度收缩率,两组间比较,差异无统计学意义(P>0.05)。结论多裂肌收缩功能可能会随飞行时间延长而降低。针对性加强多裂肌功能,可能会降低飞行人员腰背痛。超声可作为一种无创伤、无辐射、连续、便携、实时影像检查技术用于评估多裂肌功能。 相似文献
995.
Lisa M. Bodnar Barbara Abrams Lara Siminerio Timothy L. Lash 《Maternal & child nutrition》2016,12(3):632-638
Birth certificates are an important source of pre‐pregnancy body mass index (BMI) and gestational weight gain (GWG) data for surveillance and aetiologic studies, but little is known about their validity in twin pregnancies. Twins experience high rates of adverse perinatal outcomes that have been associated with BMI and GWG in singletons. Our objective was to evaluate the accuracy of birth certificate‐derived pre‐pregnancy BMI and GWG compared with medical record‐derived data in a sample of 186 twin pregnancies at a teaching hospital in Pennsylvania (2003–2010). Twelve strata were created by simultaneous stratification on pre‐pregnancy BMI (underweight, normal weight/overweight, obese class 1, obese classes 2 and 3) and GWG (<20th, 20–80th, >80th percentile). The agreement of birth certificate‐derived pre‐pregnancy BMI category with medical record BMI category was lowest among underweight mothers [75% (95% confidence interval 51–91%) ] and highest among normal/overweight [97% (90–99%) ] and obese classes 2 and 3 mothers [97% (85–99%) ]. Agreement for GWG category from the birth certificate varied from 57% (41–70%) for GWG >80th percentile to 80% (65–91%) and 82% (72–89%) for GWG <20th and 20th–80th percentiles, respectively. The misclassification of BMI and GWG was primarily due to error in pre‐pregnancy weight rather than weight at delivery or height. Agreement proportions for twins were not meaningfully different from the proportions in a comparable sample of singleton pregnancies. These data suggest that birth certificate‐based BMI and GWG data are prone to error in twin pregnancies. Those who use these data should conduct internal validation studies and adjust their results using bias analyses. 相似文献
996.
997.
Safak Ozdemirci Derya Akdag Cirik Neslihan Yerebasmaz Fulya Kayikcioglu Funda Salgur 《The journal of maternal-fetal & neonatal medicine》2016,29(20):3391-3394
Objective: To compare the obstetrical and neonatal outcomes of late adolescent (LA) and adult pregnancies.Methods: Between January 2012 and December 2012, a total of 313 late adolescent pregnant aged between 16 and 19 years and 418 adult pregnant women aged between 20 and 35 years having given birth in our maternity service were enrolled into this case–control study. The demographic and clinical data were reviewed from hospital database and patients’ medical records.Results: The incidence of preterm birth (PB) in the LA group was significantly higher than in the adult group (p?=?0.001), while the incidence of gestational diabetes mellitus was significantly lower (p?=?0.001). The mean birth weight and the rate of delivered macrosomic fetuses in the study group were lower than in the control group (p?=?0.03). The LA group had significantly higher rate of vaginal delivery when compared to the adult group (p?=?0.001). Both the rate of pregnancy induced hypertensive disorders and postpartum hemorrhage were not statistically different between the two groups (p?=?0.31; p?=?0.38, respectively). The LA group had lower rate of stillbirth when compared to the adult group; however, the difference was statistically insignificant (0.3% versus 1.2%) (p?=?0.24).Conclusions: The LA pregnancy should be closely followed up during their antenatal care period due to the significantly higher rate of PB. 相似文献
998.
Faranak Behnia Morgan Peltier Darios Getahun Cheryl Watson George Saade 《The journal of maternal-fetal & neonatal medicine》2016,29(22):3583-3589
Objective: The objective of this study is to determine if BPA exposure, as measured by maternal plasma (MP) and amniotic fluid (AF) BPA concentrations is associated with an increased risk of spontaneous preterm birth (PTB) and preterm premature rupture of membranes (pPROM).Methods: In this nested case–control study, MP samples from women in term labor (n?=?30), preterm labor that ended with preterm delivery (n?=?25), or who had pPROM (n?=?30) and amniotic fluid samples from term labor (n=?45), preterm labor (n?=?60), and pPROM (n?=?35) were assayed for BPA by enzyme immunoassay.Results: BPA was detectible in 100% of MP and AF samples. Women with MP BPA concentrations in the fourth quartile were at increased risk of PTB (cOR?=?4.12, 95% CI?=?1.32–12.87; aOR?=?4.78, 95% CI?=?1.14–20) but not pPROM. High (fourth quartile) AF BPA values also tended to increase the risk of pPROM (cOR?=?2.47, 95% CI?=?0.96–6.37) but results were not statistically significant.Conclusions: Increased BPA concentration is associated with an increased risk for PTB or pPROM depending on the maternal–fetal compartment(s) affected. High MP plasma BPA concentrations are associated with PTB with intact membranes but high AF BPA concentrations may weakly be associated with pPROM. 相似文献
999.
Felipe Tudela Simi Gupta Andrei Rebarber Daniel H. Saltzman Chad K. Klauser Nathan S. Fox 《The journal of maternal-fetal & neonatal medicine》2016,29(23):3796-3799
Objective: We sought to assess the association between maternal height and the risk of preterm birth, fetal growth restriction and mode of delivery in twin gestations.Study design: Cohort study of patients with twin pregnancies delivered from 2005 to 2014. We compared pregnancy outcomes between patients of short stature?≤159?cm to those of normal stature?≥160?cm. Patients with monoamniotic twins and major fetal anomalies were excluded. Pearson’s correlation, Chi-square and Student’s t-test were used as appropriate.Results: Six hundred and sixty-six patients were included, 159 (23.9%) of whom had short stature (mean height 155.8?±?2.5?cm) and 507 (76.1%) of whom had normal stature (mean height 167.2?±?5.5?cm). There were no differences in outcomes between the groups in regards to preterm birth, gestational age (GA) at delivery, birth weight of either twin, preeclampsia, gestational diabetes or cesarean section rate. Results were similar when the groups were stratified by parity. As a continuous variable, maternal height did not correlate with GA at delivery (p=?0.388), cesarean delivery (p?=?0.522) nor the birth weight of the larger (p?=?0.206) or smaller (p?=?0.307) twin.Conclusion: In twin pregnancies, maternal short stature is not associated with preterm birth, fetal growth restriction or cesarean section rate. This suggests that although anthropometric measurements have long been used to counsel patients in regards to outcomes, patients of short stature should be reassured that their height does not appear to lead to adverse twin pregnancy outcomes. 相似文献
1000.
目的:探讨在控制性卵巢刺激(COS)周期中晚卵泡期孕酮(P)水平变化趋势对体外受精-胚胎移植(IVF-ET)结局的影响。方法:回顾分析2013年1月至2014年6月在我中心行IVF-ET长方案助孕治疗的676个周期。按促排卵中晚卵泡期起始日(主导卵泡直径达13mm日)与人绒毛膜促性腺激素(HCG)注射日孕酮水平变化,分为升高趋势组和降低趋势组;按HCG日孕酮水平是否1.0ng/ml将升高趋势组和降低趋势组中新鲜移植周期分别分为A组(P≤1ng/ml)、B组(P1ng/ml)和C组(P≤1ng/ml)、D组(P1ng/ml)。结果:(1)升高趋势组与降低趋势组的卵裂率、优质胚胎率比较,差异有统计学意义(99.65%vs 99.00%,70.57%vs 63.09%;P0.05);(2)A组与B组的临床妊娠率、活产率比较,差异有统计学意义(56%vs 43.00%;50%vs 37.76%,P0.05);C组与D组的临床妊娠率、活产率比较,差异无统计学意义(P0.05)。结论:IVF-ET长方案周期中,COS过程中孕酮变化呈升高趋势的优质胚胎率较降低趋势高;新鲜移植周期,P呈升高趋势时,HCG日P1.0ng/ml,活产率下降;呈降低趋势时,HCG日P水平不影响活产率。 相似文献