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OBJECTIVE: To compare the impact upon maternity unit resources and finances of two protocols for induction of labour using prostaglandins. DESIGN: A prospective randomised trial comparing a single dose of prostaglandin E2 (2 mg) in the evening with two doses of prostaglandin E2 (2 mg), the second being given after six hours if labour had not started or the cervix was still unripe, followed if necessary by formal induction of labour by amniotomy and oxytocin infusion 14 to 20 hours after the initial prostaglandin E2 dose. Outcome for nulliparae and multiparae were analysed separately, by treatment intention. SETTING: A maternity unit in a district general hospital delivering > 6000 women annually. PARTICIPANTS: Nine hundred and fifty-five women with viable singleton pregnancies and cephalic presentation at term without previous history of caesarean section who were advised to have labour induced with prostaglandins. MAIN OUTCOME MEASURES: Costs incurred in managing all aspects of labour, including time spent on the antenatal ward and, in the delivery unit; costs associated with formal induction, augmentation of labour and epidural analgesia; costs of intrapartum maternal morbidity, mode of delivery and immediate neonatal care. Costs of postpartum hospital stay were estimated from unit statistics. RESULTS: The overall mean cost of induction of labour was Pounds 5.00 and Pounds 7.22 less per woman for nulliparae and multiparae, respectively, if the two dose regimen was used. The main reason for the differences was due to delivery suite costs from the slightly greater rate of assisted deliveries in the single treatment groups. In contrast, costs for neonatal care were marginally lower if only one prostaglandin dose was used. CONCLUSIONS: The increased drug costs providing two prostaglandin E2 doses when required were off-set by reductions in the costs of other intrapartum interventions for both nulliparae and multiparae. The advantages of less time spent on the antenatal ward for multiparae when two prostaglandin E2 doses were used may be eliminated if amniotomy and oxytocin infusion was commenced six hours after the initial prostaglandin dose had been given if labour had not started. 相似文献
73.
A simulation approach to assess the minimal number of real-time PCR replicates for GM quantification
The quantification of genetically modified (GM) ingredients in food and feed typically uses real-time quantitative PCR (RT-QPCR).
In recent years a multitude of new RT-QPCR assays have facilitated increased method performance. The level of sample replication
within these assays is a fundamental aspect that needs to be considered to produce results with high confidence. In this paper
we describe the use of a modelling approach as applied to GM and RT-QPCR data sets, to objectively assesses the effect of
different levels of PCR replication in terms of the variability associated with a result, and demonstrate that it is possible
to use a reduced level of replication without a subsequent reduction in the confidence of a result. Using an example data
set, we show it is possible to reduce the sample level of replication from six to three PCR replicates, without a significant
change in the mean value of the result. The use of such an approach can facilitate the use of the minimum number of replicates
in order to produce an accurate result, thus saving on important resources involved in quantification assays. 相似文献
74.
Expert classification systems have proven themselves effective decision makers for many types of problems. However, the accuracy of such systems is often highly dependent upon the accuracy of a human expert's domain theory. When human experts learn or create a set of rules, they are subject to a number of hindrances. Most significantly experts are, to a greater or lesser extent, restricted by the tradition of scholarship which has preceded them and by an inability to examine large amounts of data in a rigorous fashion without the effects of boredom or frustration. As a result, human theories are often erroneous or incomplete. To escape this dependency, machine learning systems have been developed to automatically refine and correct an expert's domain theory. When theory revision systems are applied to expert theories, they often concentrate on the reformulation of the knowledge provided rather than on the reformulation or selection of input features. The general assumption seems to be that the expert has already selected the set of features that will be most useful for the given task. That set may, however, be suboptimal. This paper studies theory refinement and the relative benefits of applying feature selection versus more extensive theory reformulation. 相似文献
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The onset of transmission loss in four single-mode tapers is shown to coincide with the taper slope exceeding the critical slope angle at which fundamental mode cutoff occurs. This implies that the primary loss mechanism in single-mode fiber tapers is cutoff of the fundamental mode from the core. A secondary loss mechanism of coupling to the modes of a coaxial outer waveguide is also observed and modeled. Implications for fused fiber couplers are discussed. 相似文献
78.
Noise measurements were made on an InGaAsP semiconductor diode laser by monitoring and analyzing the mode-locked pulse train power spectrum. The noise content of the mode-locking RF source was observed to be transferred directly to the laser pulse train and, thus, careful selection of the drive oscillator is essential. Amplification of the laser pulses by an erbium-fiber amplifier did not lead to any increase in timing jitter and the additional amplitude noise present could be removed by using a more compatible pump source such as a diode laser operating at either 980 or 1490 nm 相似文献
79.
Many of the nation's homeless people suffer from unrecognized mental illnesses and do not have access to the kind of disability benefits they would be entitled to when properly assessed. The current system of disability evaluations for Social Security income claims is frequently inadequate and leaves these individuals without any source of income, health insurance, and mental health treatment. This article introduces a model of providing psychological assessments for homeless, mentally ill individuals by supervised student examiners, a model that could be replicated by other psychologists and training institutions. The authors argue that there may be a large number of homeless adults who suffer from disabling mental conditions but who are not properly diagnosed and, therefore, do not qualify for benefits. The authors propose that the model presented can help to fill a gap in services and may serve as a model of socially relevant clinical training. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
80.