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991.
992.
Ibtisam Salim Eleonora Staines-Urias Sam Mathewlynn Lior Drukker Manu Vatish Lawrence Impey 《PLoS medicine》2021,18(1)
BackgroundBreech presentation at term contributes significantly to cesarean section (CS) rates worldwide. External cephalic version (ECV) is a safe procedure that reduces term breech presentation and associated CS. A principal barrier to ECV is failure to diagnose breech presentation. Failure to diagnose breech presentation also leads to emergency CS or unplanned vaginal breech birth. Recent evidence suggests that undiagnosed breech might be eliminated using a third trimester scan. Our aim was to evaluate the impact of introducing a routine 36-week scan on the incidence of breech presentation and of undiagnosed breech presentation.Methods and findingsWe carried out a population-based cohort study of pregnant women in a single unit covering Oxfordshire, United Kingdom. All women delivering between 37+0 and 42+6 weeks gestational age, with a singleton, nonanomalous fetus over a 4-year period (01 October 2014 to 30 September 2018) were included. The mean maternal age was 31 years, mean BMI 26, 44% were nulliparous, and 21% were of non-white ethnicity. Comparisons between the 2 years before and after introduction of routine 36-week scan were made for 2 primary outcomes of (1) the incidence of breech presentation and (2) undiagnosed breech presentation. Secondary outcomes related to ECV, mode of birth, and perinatal outcomes. Relative risks (RRs) with 95% confidence intervals (CIs) are reported. A total of 27,825 pregnancies were analysed (14,444 before and 13,381 after). A scan after 35+0 weeks was performed in 5,578 (38.6%) before, and 13,251 (99.0%) after (p < 0.001). The incidence of breech presentation at birth did not change significantly (2.6% and 2.7%) (RR 1.02; 95% CI 0.89, 1.18; p = 0.76). The rate of undiagnosed breech before labour reduced, from 22.3% to 4.7% (RR 0.21; 95% CI 0.12, 0.36; p < 0.001). Vaginal breech birth rates fell from 10.3% to 5.3% (RR 0.51; 95% CI 0.30, 0.87; p = 0.01); nonsignificant increases in elective CS rates and decreases in emergency CS rates for breech babies were seen. Neonatal outcomes were not significantly altered. Study limitations include insufficient numbers to detect serious adverse outcomes, that we cannot exclude secular changes over time which may have influenced our results, and that these findings are most applicable where a comprehensive ECV service exists.ConclusionsIn this study, a universal 36-week scan policy was associated with a reduction in the incidence but not elimination of undiagnosed term breech presentation. There was no reduction in the incidence of breech presentation at birth, despite a comprehensive ECV service.Ibtisam Salim and co-workers report on incidence of breech presentation in pregnant women receiving a 36-week scan. 相似文献
993.
994.
Ibrahim M. Gosadi Khaled A. Daghriri Abdullah A. Otayf Abdulrhman A. Nemri Abdulaziz A. Kaal Abdullah M. Qussadi Manal M. Maashi Alshaymaa M. Arishy Hadeel M. Mushafa Abdulrhman M. Salim 《Saudi Journal of Biological Sciences》2021,28(5):2951-2955
BackgroundPatient’s awareness of their clinical and laboratory parameters is an indicator of the degree of involvement in achieving their management goals. This investigation aimed to identify awareness of patients affected by chronic non-communicable diseases of their clinical and laboratory parameters and factors associated with the awareness.MethodsThis study was a cross-sectional investigation conducted in the Jazan region, between January and August 2020. Data was collected during phone interviews utilizing a semi-structured questionnaire. Odds ratios (ORs) were calculated to estimate the likelihood of awareness of each clinical and laboratory parameter according to the measured demographic variables.ResultsThe total number of recruited patients was 675. The mean age of participants was 53.7 years and the 28.7% of patients were illiterate. About 17% of the patient do not attend follow-up visits to any healthcare provider. When patients were asked about their parameters, 87% of them were able to report their body weight and 74% were able to report their height. However, less than half of patients were aware of their glycated hemoglobin level (HbA1c) (271/675 patients) and systolic blood pressure (BP) level (329/ 675 patients), and a minority were aware of their total cholesterol level (71/675 patients). Being female, resident in a rural area, illiterate, and older than 53 was strongly associated with high odds of limited awareness about their own clinical and laboratory parameters (P values < 0.05).ConclusionAwareness of patients affected by chronic non-communicable diseases of their own clinical and laboratory parameters in the Jazan region is sub-optimal where this limited awareness is likely to be associated with the lower engagement of patients with achieving their desired management targets. 相似文献
995.
Mustafa Al-Saiedy Ryan Pratt Patrick Lai Evan Kerek Heidi Joyce Elmar Prenner Francis Green Chang-Chun Ling Ruud Veldhuizen Salim Ghandorah Matthias Amrein 《Biochimica et Biophysica Acta (BBA)/General Subjects》2018,1862(4):1040-1049
Pulmonary surfactant forms a cohesive film at the alveolar air-lung interface, lowering surface tension, and thus reducing the work of breathing and preventing atelectasis. Surfactant function becomes impaired during inflammation due to degradation of the surfactant lipids and proteins by free radicals. In this study, we examine the role of reactive nitrogen (RNS) and oxygen (ROS) species on surfactant function with and without physiological cholesterol levels (5–10%). Surface activity was assessed in vitro in a captive bubble surfactometer (CBS). Surfactant chemistry, monolayer fluidity and thermodynamic behavior were also recorded before and after oxidation. We report that physiologic amounts of cholesterol combined with oxidation results in severe impairment of surfactant function. We also show that surfactant polyunsaturated phospholipids are the most susceptible to oxidative alteration. Membrane thermodynamic experiments showed significant surfactant film stiffening after free radical exposure in the presence of cholesterol. These results point to a previously unappreciated role for cholesterol in amplifying defects in surface activity caused by oxidation of pulmonary surfactant, a finding that may have implications for treating several lung diseases. 相似文献
996.
997.
The crystal structure of the human DNA repair endonuclease HAP1 suggests the recognition of extra-helical deoxyribose at DNA abasic sites. 总被引:14,自引:1,他引:13 下载免费PDF全文
M A Gorman S Morera D G Rothwell E de La Fortelle C D Mol J A Tainer I D Hickson P S Freemont 《The EMBO journal》1997,16(21):6548-6558
The structure of the major human apurinic/ apyrimidinic endonuclease (HAP1) has been solved at 2.2 A resolution. The enzyme consists of two symmetrically related domains of similar topology and has significant structural similarity to both bovine DNase I and its Escherichia coli homologue exonuclease III (EXOIII). A structural comparison of these enzymes reveals three loop regions specific to HAP1 and EXOIII. These loop regions apparently act in DNA abasic site (AP) recognition and cleavage since DNase I, which lacks these loops, correspondingly lacks AP site specificity. The HAP1 structure furthermore suggests a mechanism for AP site binding which involves the recognition of the deoxyribose moiety in an extrahelical conformation, rather than a 'flipped-out' base opposite the AP site. 相似文献
998.
999.
Salim Zerrouk Olga Escuredo María Shantal Rodríguez-Flores María Carmen Seijo 《Grana》2021,60(1):69-80
Abstract A melissopalynological study was carried out on 46 samples of Ziziphus lotus honey from Laghouat and Djelfa region (central Algeria). The number of pollen types identified per honey sample ranges between nine and 39 with a mean of 24. These correspond to 52 botanical families with 79 different pollen types in the whole samples. Asteraceae and Fabaceae families were present in all the samples where as Apiaceae, Brassicaceae and Nitrariaceae (Peganum harmala) were identified in more than 90%. Other plant families as Boraginaceae, Cistaceae, Myrtaceae, Oleaceae, Salicaceae or Urticaceae were identified in more than 50% of the samples but frequently as minor pollen. Ziziphus lotus pollen had a mean content of 68.9% (with a range of 45.3% to 93.4%). The secondary pollen types were Ononis natrix, Peganum harmala, Brassica napus, Echium and Olea europaea. Regarding the important pollen it is highlighted the presence Lotus t., Eucalyptus, Pimpinella anisum t., Trifolium t., Eryngium campestre t., Centaurea t., Galega officinalis t., Citrus or Scrophularia t. The sedra honeys of the studied region are characterised by their high content in pollen grains with a mean content of 188 403 grains/10 g. The presence of some pollen types in the pollen spectra of honeys such as Peganum harmala, Thapsia garganica, Launaea, Muscari comosum, Carthamus or Limonium bonduellei together several Asteraceae as Centaurea, Taraxacum, Carduus, Artemisia and Matricaria was proposed as geographical markers of this honey type. 相似文献
1000.