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111.
Ida N?slund Thagaard Lone Krebs Ulrik Lausten-Thomsen Severin Olesen Larsen Jens-Christian Holm Michael Christiansen Torben Larsen 《PloS one》2016,11(1)
Objectives
To evaluate in a national standardised setting whether the performance of ultrasound dating during the first rather than the second trimester of pregnancy had consequences regarding the definition of pre- and post-term birth rates.Methods
A cohort study of 8,551 singleton pregnancies with spontaneous delivery was performed from 2006 to 2012 at Copenhagen University Hospital, Holbæk, Denmark. We determined the duration of pregnancy calculated by last menstrual period, crown rump length (CRL), biparietal diameter (1st trimester), BPD (2nd trimester), and head circumference and compared mean and median durations, the mean differences, the systematic discrepancies, and the percentages of pre-term and post-term pregnancies in relation to each method. The primary outcomes were post-term and pre-term birth rates defined by different dating methods.Results
The change from use of second to first trimester measurements for dating was associated with a significant increase in the rate of post-term deliveries from 2.1–2.9% and a significant decrease in the rate of pre-term deliveries from 5.4–4.6% caused by systematic discrepancies. Thereby 25.1% would pass 41 weeks when GA is defined by CRL and 17.3% when BPD (2nd trimester) is used. Calibration for these discrepancies resulted in a lower post-term birth rate, from 3.1–1.4%, when first compared to second trimester dating was used.Conclusions
Systematic discrepancies were identified when biometric formulas were used to determine duration of pregnancy. This should be corrected in clinical practice to avoid an overestimation of post-term birth and unnecessary inductions when first trimester formulas are used. 相似文献112.
G V Abramochkin E N Ratner V V Petrov A I Severin N E Suzina B A Fikhte I S Kulaev 《Prikladnaia biokhimiia i mikrobiologiia》1990,26(1):93-100
The effect of the bacteriolytic preparation "Lysoamidase" on Staphylococcus aureus 299 P was studied. The maximum activity of the preparation was observed at pH 8.0 ionic strength 0.01-0.02 M and 50-60 degrees of the incubation medium. The electron microscopic examination revealed that "Lysoamidase" hydrolyzed the cell wall in one or several points with the following osmotic shock and extrusion of the cytoplasm. In an isotonic solution (1 M sucrose) "Lysoamidase" caused protoplast formation. 相似文献
113.
114.
This is an analytic study of mucous flow caused by ciliary motion. The computed flow data may be compared with that already
found exprimentally. The effects of mucous density, viscosity and layer depth on flow phenomena are investigated. The effects
of cilia diameter, length, spacing and oscillation frequency are determined from the equations governing the flow of the mucous
blanket. A pertinent finding of the analysis is that the mucous flow in the airway tubes can satisfy physical constraints
only through the assumption of a variable viscosity in the covering mucous blanket. The mucous viscosity must increase considerably
from the low value at the cillium layer to a much higher value at the air-mucus interface. 相似文献
115.
A I Glukhov A O Benyumov K G Gazaryan M V Nesterova E S Severin 《Biochemistry international》1984,9(1):83-91
The level of cAMP and the effects of the regulatory and catalytic subunits of cAMP-dependent protein kinase of type II on protein, RNA and DNA synthesis in loach embryos were analysed. It was found that the injections of the catalytic subunit cause a sharp decrease in the rate of macromolecular synthesis while an increase in the concentration of this protein leads to the death of the embryo. Injections of the regulatory subunit result in marked stimulation of protein, RNA and DNA synthesis. The effect of the regulatory subunit on these processes is rather complex. Experiments on the transplantation of the nuclei from the embryos treated with the protein kinase subunits into normal embryos were carried out. 相似文献
116.
G. Lognay M. Marlier F. Crahay J. P. Mampuys M. Severin Ph. Tnonart 《Biotechnology letters》1987,9(7):467-470
Summary Six sterols were extracted from lipids produced by Candida curvata yeast. Ergosterol (main component) and five minor compounds: ergosta-7, 24(28)-dien-3 -ol, ergosta-5, 7-dien-3 -ol, ergosta-5, 7, 9, (11), 22-tetraen-3 -ol, ergosta 7, 22-dien-3 -ol, ergost-7-en-3 -ol were identified by gas chromafography/mass spectrometry (GCMS) and quantitated by GLC. 相似文献
117.
The influence of nerve growth factor on the activities of adenylate cyclase and high-affinity GTPase in pheochromocytoma PC12 cell 总被引:1,自引:0,他引:1
The influence of nerve growth factor (NGF) on the activities of adenylate cyclase and high-affinity GTPase in pheochromocytoma PC12 cells was studied. Incubation of cells with nerve growth factor led to a rapid activation of adenylate cyclase accompanied by an inhibition of high-affinity GTPase. By the 10th min of incubation the activity of adenylate cyclase had been reduced 2-fold when compared to the control. The activity of GTPase, however, increased. No significant changes in the cAMP level were detected. The data obtained indicate that NGF interaction with PC12 cells induces changes in the adenylate cyclase system and this process involves G-proteins that regulate the adenylate cyclase activity. 相似文献
118.
A.V. Kabanov A.V. Ovcharenko N.S. Melik-Hubarov A.I. Bannikov V.Yu. Alakhov V.I. Kiselev P.G. Sveshnikov O.I. Kiselev A.V. Levashov E.S. Severin 《FEBS letters》1989,250(2):238-240
A method for suppression of virus reproduction in cells using fatty acylated antiviral antibodies, which in contrast to non-modified antibodies are capable of intracellular penetration, has been suggested. The addition of stearoylated antiviral antibodies to influenza A/Chili virus-infected cells causes a 100-fold suppression of virus reproduction. Non-modified antibodies do not produce any effect on virus reproduction. 相似文献
119.
Synapsin I has been isolated from human brain by a rapid and efficient purification technique, and its phosphorylation by human brain Ca2+, phospholipid-dependent protein kinase (protein kinase C) has been studied. The inhibitory effect of calmodulin on this process has been demonstrated. It is also found that non-esterified fatty acids and acidic phospholipids are inhibitory for synapsin I phosphorylation by Ca2+, calmodulin-dependent protein kinase II. 相似文献
120.