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551.
552.
NN Finer A Tierney PC Etches A Peliowski W Ainsworth 《Canadian Metallurgical Quarterly》1998,33(9):1331-1337
BACKGROUND/PURPOSE: The purpose of this study was to evaluate the evolving outcome of newborns who have congenital diaphragmatic hernia (CDH) using a protocolized approach to management, which includes extracorporeal membrane oxygenation (ECMO) and to present the details of such a management protocol. METHODS: A retrospective chart review was conducted of the neonatal outcome of near-term (>34 weeks' gestation) newborns with CDH all referred to the Royal Alexandra Hospital either before or after delivery. A protocol was developed that included antenatal assessment, the use of antenatal steroids, planned delivery, use of prophylactic surfactant, pressure limited gentle ventilation, permissive hypercarbia and hypoxia, and venovenous ECMO, if indicated. RESULTS: Sixty-five infants with CDH were treated from February 1989 through August 1996. Twenty-three infants were inborn, 20 of whom were antenatal referrals. Overall, 51 of the 65 infants survived (78%). Thirteen of the 23 inborn infants survived with conservative management, and 10 required ECMO, of whom, eight were long-term survivors. Thirty-eight infants required ECMO, and 26 survived (68%), whereas there were only two deaths among the 27 conservatively treated infants. Eighteen of 20 inborn infants with an antenatal diagnosis survived, compared with 13 of 21 (62%) outborn infants. An antenatal diagnosis before 25 weeks' gestation was associated with a 60% survival rate. Sixty-three percent of infants whose best postductal PaO2 value before ECMO was less than 100 torr survived, and 7 of 11 infants with a best postductal PaO2 value of less than 50 torr before ECMO survived (64%). The average age at surgery progressively increased over time both for infants who did not require ECMO (1.3 days to 5.8 days; P = .01) and for infants who received ECMO (1.9 days to 8.2 days; P = .016). CONCLUSIONS: The use of a protocolized management for infants with CDH has been associated with improving outcome in a population at high risk. The components (either separately or combined) of these protocolized approaches need to be tested in prospective trials to determine their true benefit. In addition, there is a need to evaluate prospectively the outcomes of infants with CDH born in ECMO centers compared with those infants born in other tertiary care neonatal units to determine the most appropriate management of the fetus with CDH. 相似文献
553.
554.
Matrix-assisted laser desorption/ionization (MALDI) probe surfaces derivatized with octadecanethiol (C18) can be used as hydrophobic solid-phase extraction devices to isolate and desalt biopolymers directly on the probe surface. Using quantitative MALDI, it was possible to determine the approximate amount of peptide that bound to C18 surfaces and thus to calculate a surface density. It was determined that the amount of peptide bound at the probe surface was independent of the analyte concentration in the immersion solution (from high- to sub-ng ml-1 concentrations), but rather was dependent on the immersion time of the surface as it was exposed to the analyte. The capacity of C18-derivatized probes to bind biopolymers in fixed amounts frees the analyst from the necessity for adjusting analyte concentration through multiple step procedures such as serial dilution or vacuum drying. This time savings result in an overall increase in the efficiency of the MALDI technique. 相似文献
555.
Mycoplasma infection may lead to various pathologies in a broad range of hosts. It has been shown that Mycoplasma may trigger cell death in cell cultures; however, the mechanism remains unknown. In the present paper we show that Mycoplasma infection of different lymphocyte and epithelial tumour cell lines leads to the inhibition of proliferation, and increased cell death, accompanied by DNA fragmentation and the morphological features of apoptosis. We also showed that this infection leads to an increased sensitivity of cells to various inducers of apoptosis targeting different signalling pathways. Finally, we show that increased apoptosis is associated with overexpression of an endonuclease produced by Mycoplasma. This endonuclease is recovered in the nuclear fraction of host cells, introduces mostly DSB and is active at neutral pH in the presence of divalent cations. Activation of this endonuclease is connected with limited proteolysis, which may be reproduced in vitro by snake venom serine proteinase. 相似文献