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61.
Introduction and hypothesis
To evaluate lower urinary tract injuries in women with ≥2 prior cesarean deliveries (CD) undergoing benign hysterectomies.Methods
This is a planned secondary analysis of all hysterectomies performed from 2000 to 2009 at Grady Memorial Hospital. Demographic, operative and postoperative data were reviewed. Women undergoing benign hysterectomies with ≥2 CD were compared with women with no prior CD. Categorical variables were analyzed using Chi-squared or Fisher’s exact test, while Student’s t test was used for continuous variables. Logistic regression was used for multivariate analysis.Results
2,214 women met the inclusion criteria (284 with ≥2 CD, 1,930 with no CD). The proportion of women having vaginal hysterectomy, abdominal hysterectomy, and laparoscopically assisted vaginal hysterectomy were 38 %, 53 %, and 9 % respectively. Women with multiple CD had greater blood loss and longer operative times. They also required more transfusions (23 % vs 15 %, P?=?0.001) and developed more abdominal wounds (6 % vs 3 %, P?=?0.002) or urinary infections (6 % vs 3 %, P?=?0.03). Women with ≥2 CD were at greater risk of incidental cystotomies (OR: 8.55, 95 % CI: 3.98–18.36).Conclusions
Multiple prior cesarean deliveries increase a woman’s risk of cystotomy during hysterectomy. They also require more transfusions and develop more urinary or abdominal wound infections. 相似文献62.
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64.
Nguyen My Nuong Nguyen Thuy Vy Ho-Huynh Thuy Duong 《African journal of traditional, complementary, and alternative medicines》2014,11(4):136-141
Background
Traditional formulae usually exhibit therapeutic effects through the combinations of different ingredients. The purpose of this study was to investigate in vitro anti-oxidative activity of Thanh Hao Miet Giap Thang (THMGT) (Sweet Wormwood and Tortoise Shell Decoction) formula and the interactions of its ingredients leading to the overall anti-oxidative effect.Materials and Methods
We prepared 31 combinations containing two to four of the five ingredients including Herba Artemisia apiacea L (HbA), Carapax Trionycis (Tryonix sinensis) (CT), Rhizoma Anemarrhenae (Anemarrhena asphodeloides) (RzA), Radix Rehmanniae (Rehmannia glutinosa Libosch) (RdR), Moutan Cortex (Paeonia suffruticosa) (MC). These combinations were tested for anti-oxidative activity using DCFH-DA and DPPH assays on Hep G2 cells. We also analyzed changes in expression of genes involved in antioxidant defense system including Nuclear Factor Erythroid-Derived 2-Like 2 (NFE2L2), catalase (CAT), heme oxygenase-1 (HO-1), glutathione peroxidase (GPx), cytoplasmic superoxide dismutase (SOD1), mitochondrial superoxide dismutase (SOD2).Results
The complete formula and all combinations containing Moutan Cortex showed high antioxidant activity in both radical solution-based chemical assay and cellular-based assay. On the contrary, Carapax Trionycis displayed inhibitory effect on the overall antioxidant activity when present in a combination, an effect clearly emphasized in cellular-based assay. Hep G2 cells treated with the formula showed increased gene expression of HO-1 and SOD2 while expression of CAT, SOD1, GPx was unchanged.Conclusion
Our results suggested that THMGT had anti-oxidative activity essentially through intrinsic reducing capacities and the overall activity of the formula resulted from enhancing and inhibiting interactions of ingredients. 相似文献65.
Thi Le Anh Nguyen Thi Hoai Nam Doan Dinh Hieu Truong Nguyen Thi Ai Nhung Duong Tuan Quang Dorra Khiri Sonia Taamalli Florent Louis Abderrahman El Bakali Duy Quang Dao 《RSC advances》2021,11(35):21433
Antioxidant and UV absorption activities of three aaptamine derivatives including piperidine[3,2-b]demethyl(oxy)aaptamine (C1), 9-amino-2-ethoxy-8-methoxy-3H-benzo[de][1,6]naphthyridine-3-one (C2), and 2-(sec-butyl)-7,8-dimethoxybenzo[de]imidazo[4,5,1-ij][1,6]-naphthyridin-10(9H)-one (C3) were theoretically studied by density functional theory (DFT). Direct antioxidant activities of C1–C3 were firstly evaluated via their intrinsic thermochemical properties and the radical scavenging activity of the potential antioxidants with the HOO˙/HO˙ radicals via four mechanisms, including: hydrogen atom transfer (HAT), single electron transfer (SET), proton loss (PL) and radical adduct formation (RAF). Kinetic calculation reveals that HOO˙ scavenging in water occurs via HAT mechanism with C1 (kapp, 7.13 × 106 M−1 s−1) while RAF is more dominant with C2 (kapp, 1.40 × 105 M−1 s−1) and C3 (kapp, 2.90 × 105 M−1 s−1). Antioxidant activity of aaptamine derivatives can be classified as C1 > C3 > C2. Indirect antioxidant properties based on Cu(i) and Cu(ii) ions chelating activity were also investigated in aqueous phase. All three studied compounds show spontaneous and favorable Cu(i) ion chelating activity with ΔG0 being −15.4, −13.7, and −15.7 kcal mol−1, whereas ΔG0 for Cu(ii) chelation are −10.4, −10.8, and −2.2 kcal mol−1 for C1, C2 and C3, respectively. In addition, all compounds show UVA and UVB absorption; in which the excitations are determined mostly as π–π* transition. Overall, the results suggest the potential applications of the aaptamines in pharmaceutics and cosmetics, i.e. as a sunscreen and antioxidant ingredient.Antioxidant and UV absorption activities of three aaptamine derivatives were theoretically studied by density functional theory (DFT) and time-dependent density functional theory (TD-DFT). 相似文献
66.
67.
Ngo Tuan Cuong Nguyen Thi Mai Nguyen Thanh Tung Ngo Thi Lan Long Van Duong Minh Tho Nguyen Nguyen Minh Tam 《RSC advances》2021,11(63):40072
Geometrical and electronic structures of the 13-atom clusters AlxScy with x + y = 13, as well as their thermodynamic stabilities were investigated using DFT calculations. Both anionic and neutral isomers of AlxScy were found to retain an icosahedral shape of both Al13 and Sc13 systems in which an Al atom occupies the endohedral central position of the icosahedral cage, irrespective of the number of Al atoms present. Such a phenomenon occurs to maximize the number of stronger Al–Al and Sc–Al bonds instead of the weaker Sc–Sc bonds. NBO analyses were applied to examine their electron configurations and rationalize the large number of open shells and thereby high multiplicities of the mixed clusters having more than three Sc atoms. The SOMOs are the molecular orbitals belonged to the irreducible representations of the symmetry point group of the clusters studied, rather than to the cluster electron shells. Evaluation of the average binding energies showed that the thermodynamic stability of AlxScy clusters is insignificantly altered as the number y goes from 0 to 7 and then steadily decreases when y attains the 7–13 range. Increase of the Sc atom number also reduces the electron affinities of the binary AlxScy clusters, and thus they gradually lose the superhalogen characteristics with respect to the pure Al13.The icosahedral structure of the AlxScy clusters with x + y = 13. 相似文献
68.
Rupa Narayan MD Traci M. Blonquist MS Ashkan Emadi MD PhD Robert P. Hasserjian MD Meghan Burke BS Christopher Lescinskas BS Donna S. Neuberg ScD Andrew M. Brunner MD Gabriela Hobbs MD Hanno Hock MD PhD Steven L. McAfee MD Yi-Bin Chen MD Eyal Attar MD Timothy A. Graubert MD Christina Bertoli MSN Jenna A. Moran MSN Meghan K. Bergeron MSN Julia E. Foster MSN Aura Y. Ramos BSN Tina T. Som BSN Megan K. Vartanian BSN RN Jennifer L. Story LPN Kristin McGregor MS Molly Macrae BS Tanya Behnan BS Margaret C. Wey PhD Jessica Rae BSN Frederic I. Preffer PhD Patricia Lesho BA Vu H. Duong MD Mason L. Mann BA Karen K. Ballen MD Christine Connolly BS Philip C. Amrein MD Amir T. Fathi MD 《Cancer》2020,126(6):1264-1273
69.
70.
Guillaume Doucet Roberto A. Gulli Benjamin W. Corrigan Lyndon R. Duong Julio C. Martinez‐Trujillo 《Hippocampus》2020,30(3):192-209
Primates use saccades to gather information about objects and their relative spatial arrangement, a process essential for visual perception and memory. It has been proposed that signals linked to saccades reset the phase of local field potential (LFP) oscillations in the hippocampus, providing a temporal window for visual signals to activate neurons in this region and influence memory formation. We investigated this issue by measuring hippocampal LFPs and spikes in two macaques performing different tasks with unconstrained eye movements. We found that LFP phase clustering (PC) in the alpha/beta (8–16 Hz) frequencies followed foveation onsets, while PC in frequencies lower than 8 Hz followed spontaneous saccades, even on a homogeneous background. Saccades to a solid grey background were not followed by increases in local neuronal firing, whereas saccades toward appearing visual stimuli were. Finally, saccade parameters correlated with LFPs phase and amplitude: saccade direction correlated with delta (≤4 Hz) phase, and saccade amplitude with theta (4–8 Hz) power. Our results suggest that signals linked to saccades reach the hippocampus, producing synchronization of delta/theta LFPs without a general activation of local neurons. Moreover, some visual inputs co‐occurring with saccades produce LFP synchronization in the alpha/beta bands and elevated neuronal firing. Our findings support the hypothesis that saccade‐related signals enact sensory input‐dependent plasticity and therefore memory formation in the primate hippocampus. 相似文献