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101.
Transport properties of the halogeno-alkali oxides A3OX (A = Li, Na, X = Cl, Br) nanocrystalline samples with the presence of ∑3(111) grain boundaries were computed using large-scale molecular dynamic simulations. Results on the diffusion/conduction process show that these nanocrystalline samples are characterized with higher activation energies as compared to previous theoretical studies, but closer to experiment. Such a performance can be attributed to the larger atomic density at the ∑3(111) grain boundary regions within the nanocrystals. Despite a minor deterioration of transport properties of the mixed cation Li2NaOX and Na2LiOX samples, these halogeno-alkali oxides can also be considered as good inorganic solid electrolytes in both Li- and Na-ion batteries.Transport properties of the halogeno-alkali oxides A3OX (A = Li, Na, X = Cl, Br) nanocrystalline samples with the presence of ∑3(111) grain boundaries were computed using large-scale molecular dynamic simulations. 相似文献
102.
103.
NF-kappaB is known to play a crucial role in the regulation of genes controlling the immune system, apoptosis, tumor cell growth, and tissue differentiation. Bioassay-guided fractionation of the n-hexane-soluble fraction of a methanol extract of Amorpha fruticosa afforded four new compounds, 5, 7, 8, and 9, and eight known compounds. Their structures were elucidated by spectroscopic methods. All compounds inhibited NF-kappaB activity, and tephrosin (1), 11-hydroxytephrosin (2), and deguelin (3) were the most active, with IC50 values of 0.11, 0.19, and 0.22 microM, respectively, in TNF-alpha-stimulated HeLa cell-based reporter gene assays. Further investigations showed that compounds 1, 5, and 6 blocked NF-kappaB/DNA binding activity and suppressed the expression of NF-kappaB target genes. 相似文献
104.
Thuong PT Lee CH Dao TT Nguyen PH Kim WG Lee SJ Oh WK 《Journal of natural products》2008,71(10):1775-1778
Phytochemical study on a methanol-soluble extract of the leaves of persimmon (Diospyros kaki) resulted in the isolation of two new ursane-type triterpenoids, 3alpha,19alpha-dihydroxyurs-12,20(30)-dien-24,28-dioic acid (1) and 3alpha,19alpha-dihydroxyurs-12-en-24,28-dioic acid (2), together with 12 known ursane- and oleanane-type triterpenoids (3-14). Triterpenoids with a 3beta-hydroxy group were found to inhibit protein tyrosine phosphatase 1B (PTP1B) activity, with IC50 values ranging from 3.1+/-0.2 to 18.8+/-1.3 microM, whereas those with a 3alpha-hydroxy moiety were not active. 相似文献
105.
Pihl K Sørensen TL Nørgaard-Pedersen B Larsen SO Nguyen TH Krebs L Larsen T Christiansen M 《Prenatal diagnosis》2008,28(3):247-253
OBJECTIVE: To establish the relationship between the first-trimester screening markers [pregnancy-associated plasma protein A (PAPP-A), free human chorionic gonadotrophin-beta (beta-hCG), nuchal translucency (NT)], the Down syndrome (DS) risk estimate, and the adverse outcomes such as low birth weight, small for gestational age (SGA) and pre-term delivery. METHODS: A retrospective cohort study including 1,734 non-selected singleton pregnancies consecutively enrolled into the programme of first-trimester combined screening for DS in a 12-month period at a single centre. Data from the Prenatal Patient Registry in ASTRAIA were combined with the Danish National Newborn Screening Registry and Danish Birth Registry. RESULTS: There was a significant relation between low PAPP-A MoM, low beta-hCG MoM, increased risk estimate for DS and low birth weight and SGA. Low PAPP-A MoM and increased NT showed a significant relation to pre-term and spontaneous pre-term delivery. Low PAPP-A MoM showed a significant relation to early pre-term delivery. CONCLUSION: First-trimester screening markers exhibited a significant relation to low birth weight, SGA and to some extent, to pre-term and early pre-term delivery. The screening performance of individual markers was poor. 相似文献
106.
107.
Carbonne B Nguyen A 《Journal de gynecologie, obstetrique et biologie de la reproduction》2008,37(Z1):S65-S71
The wide use of continuous of fetal heart rate monitoring (FHR) since the seventies has been accompanied by an increase in cesarean delivery rates, without any decrease in cerebral palsy rate. Second line methods of fetal monitoring have been developed in order to better identify fetuses truly at risk of intrapartum asphyxia. The use of fetal scalp blood sampling (FBS) for fetal monitoring seems logical since neonatal acidosis is one of the major criteria of birth asphyxia. Studies show that the use of FBS reduces the increase in cesarean deliveries associated with the use of continuous FHR monitoring. However, FBS is invasive, non continuous and technically uneasy, with a rather high rate of failed blood samplings. Fetal scalp lactates measurement by micromethod requires a much smaller volume of blood. Although a wider assessment is required, the predictive value of fetal blood lactates seems to be similar to that of fetal scalp blood pH. 相似文献
108.
Soongho Park Vinay Veluvolu William S. Martin Thien Nguyen Jinho Park Dan L. Sackett Claude Boccara Amir Gandjbakhche 《Biomedical optics express》2022,13(6):3187
We present a novel method that can assay cellular viability in real-time using supervised machine learning and intracellular dynamic activity data that is acquired in a label-free, non-invasive, and non-destructive manner. Cell viability can be an indicator for cytology, treatment, and diagnosis of diseases. We applied four supervised machine learning models on the observed data and compared the results with a trypan blue assay. The cell death assay performance by the four supervised models had a balanced accuracy of 93.92 ± 0.86%. Unlike staining techniques, where criteria for determining viability of cells is unclear, cell viability assessment using machine learning could be clearly quantified. 相似文献
109.
David J. Delgado-Diaz Dhanasekaran Sakthivel Hanh H. T. Nguyen Khashayar Farrokzhad William Hopper Charles A. Narh Jack S. Richards 《Viruses》2022,14(6)
The COVID-19 pandemic has resulted in an unprecedented global demand for in vitro diagnostic reagents. Supply shortages and hoarding have impacted testing capacity which has led to inefficient COVID-19 case identification and transmission control, predominantly in developing countries. Traditionally, RNA extraction is a prerequisite for conducting SARS-CoV-2 nucleic acid amplification tests (NAAT); however, simplified methods of sample processing have been successful at bypassing typical nucleic acid extraction steps, enabling extraction-free SARS-CoV-2 NAAT workflows. These methods involve chemical and physical approaches that are inexpensive and easily accessible alternatives to overcome extraction kit supply shortages, while offering acceptable test performance. Here we provide an overview of three main sample preparation strategies that have been shown to facilitate extraction-free SARS-CoV-2 NAATs. 相似文献
110.