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101.
A Howie H A Leaver N H Wilson P L Yap I D Aitken 《Prostaglandins, leukotrienes, and essential fatty acids》1992,46(2):111-121
The effect of dietary fatty acids on uterine fatty acid composition was studied in rats fed control diet or semi-synthetic diet supplemented with 1.5 microliter/g/day evening primrose oil (EPO) or fish oil (FO). Diet-related changes in uterine lipid were detected within 21 days. Changes of 2- to 20-fold were detected in the uterine n-6 and n-3 essential fatty acids (EFA) and in certain saturated and monounsaturated fatty acids. The FO diet was associated with higher uterine C20 and C22 n-3, and the EPO diet, with higher uterine n-6 fatty acid. High uterine C18:2 n-6 was detected in neutral lipid (NL) of rats fed high concentrations of this fatty acid, but there was little evidence of selective incorporation or retention of C18:2 n-6 by uterine NL. The incorporation of EFA into uterine phospholipids (PL) was greater than NL EFA incorporation, and uterine PL n-3/n-6 ratios showed greater diet dependence. Tissue/diet fatty acid ratios in NL and PL also indicated preferential incorporation/synthesis of C16:1 n-9, and C16:0, and there was greater incorporation of C12:0 and C14:0 into uteri of rats fed EPO and FO. Replacement of 50-60% of arachidonate with n-3 EFA in uterine PL may inhibit n-6 EFA metabolism necessary for uterine function at parturition. 相似文献
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J. W. Howie 《BMJ (Clinical research ed.)》1966,1(5481):189-192
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ObjectiveTo compare the effect of admission cardiotocography and Doppler auscultation of the fetal heart on neonatal outcome and levels of obstetric intervention in a low risk obstetric population.DesignRandomised controlled trial.SettingObstetric unit of teaching hospitalParticipantsPregnant women who had no obstetric complications that warranted continuous monitoring of fetal heart rate in labour.InterventionWomen were randomised to receive either cardiotocography or Doppler auscultation of the fetal heart when they were admitted in spontaneous uncomplicated labour.ResultsThere were no significant differences in the incidence of metabolic acidosis or any other measure of neonatal outcome among women who remained at low risk when they were admitted in labour. However, compared with women who received Doppler auscultation, women who had admission cardiotocography were significantly more likely to have continuous fetal heart rate monitoring in labour (odds ratio 1.49, 95% confidence interval 1.26 to 1.76), augmentation of labour (1.26, 1.02 to 1.56), epidural analgesia (1.33, 1.10 to 1.61), and operative delivery (1.36, 1.12 to 1.65).ConclusionsCompared with Doppler auscultation of the fetal heart, admission cardiotocography does not benefit neonatal outcome in low risk women. Its use results in increased obstetric intervention, including operative delivery.
What is already known on this topic
The admission cardiotocogram is a short recording of the fetal heart rate immediately after admission to the labour wardOpinion varies about its value in identifying a potentially compromised fetusIn low risk women, the incidence of intrapartum fetal compromise is lowWhat this study adds
Compared with Doppler auscultation of the fetal heart, admission cardiotocography has no benefit on neonatal outcome in low risk womenAdmission cardiotocography results in increased obstetric intervention, including operative delivery 相似文献106.
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Phillips AT Pankaj P Howie CR Usmani AS Simpson AH 《Computer methods in biomechanics and biomedical engineering》2006,9(3):125-133
The study investigates the short-term behaviour of the acetabular construct following revision hip arthroplasty, carried out using the Slooff-Ling impaction grafting technique; using 3D finite element analyses. An elasto-plastic material model is used to describe the constitutive behaviour of morsellised cortico-cancellous bone (MCB) graft, since it has been shown that MCB undergoes significant plastic deformation under normal physiological loads. Based on previous experimental studies carried out by the authors and others, MCB is modelled using non-linear elasticity and Drucker Prager Cap (DPC) plasticity. Loading associated with walking, sitting down, and standing up is applied to the acetabular cup through a femoral head using smooth sliding surfaces. The analyses yield distinctive patterns of migration and rotation due to different activities. These are found to be similar to those observed in the clinical setting. 相似文献
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Ota T Degani A Zubiate B Wolf A Choset H Schwartzman D Zenati MA 《Innovations (Philadelphia, Pa.)》2006,1(6):335-340
OBJECTIVE: Minimally invasive epicardial atrial ablation to cure atrial fibrillation through the use of a percutaneous subxiphoid approach currently has a lack of dedicated technology for intrapericardial navigation around the beating heart. We have developed a novel articulated robotic medical probe and performed preliminary experiments in a porcine preparation. METHODS: In five large, healthy pigs, the teleoperated robotic system was introduced inside the pericardial space through a percutaneous subxiphoid approach. Secondary visualization of the left atrium and left atrial appendage was achieved with the use of a 5-mm scope inserted through a left thoracic port. The operator actively controlled the path of the robot by using a master manipulator. The catheter, with an irrigated radiofrequency tip, was guided through the working port of the robot to achieve epicardial ablation of the left atrium. RESULTS: Access to the pericardial space and progression around the left atrium was successful in all cases, with no interference with the beating heart such as a fatal arrhythmia, unexpected bleeding, and hypotension. Epicardial ablation was successfully performed in all five cases. No adverse hemodynamic or electrophysiological events were noted during the trials. When the animals were killed, there was no visually detected injury on the surrounding mediastinal structures caused by ablation. Transmural ablation was confirmed by histopathology of the left atrium. CONCLUSIONS: We have developed a dedicated articulated robotic medical probe and successfully performed epicardial left atrial radiofrequency ablation. Based on the feedback from these preliminary experiments, the radius of curvature and proper visualization of the device are being improved in the next generation prototype. 相似文献