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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   
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Red mud, a toxic waste product from bauxite processing, was used as a catalyst for the synthesis of multi-walled carbon nanotubes (MWCNTs) by fluidised bed chemical vapour deposition. The products were analysed using thermogravimetric analysis, Raman spectroscopy, and transmission electron microscopy. Using ethylene at 650 °C a MWCNT yield of 375% (with respect to Fe loading) was obtained. Carbon products were approximately 75% MWCNTs with an IG/ID ratio from Raman spectroscopy of 1.43. The production technique and reaction conditions used are conducive to large-scale CNT production, offering a potential value-added commercial use for red mud.  相似文献   
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A method which was developed to compare the stress–strain properties of three types of thin-walled, commercially pure titanium tubes is presented. The tubes were of types intended for use in large heat-exchanger applications and were to be subjected to significant plastic deformation during subsequent assembly processes. It had been anticipated that small differences in chemical composition and tube-drawing treatment would produce quite different characteristics. It is known that the properties of titanium can exhibit considerable degrees of anisotropy, especially for wrought products; although axial properties of the materials could be evaluated using standard test equipment and procedures, a novel testing system had to be designed to allow the circumferential properties to be assessed. Significant differences between tube types were observed and anisotropic material behaviour was apparent.  相似文献   
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New fibre-reinforced composites of aluminosilicate inorganic polymer (geopolymer) with natural protein-based fibres (carpet and Merino wool) were developed, and their mechanical properties determined. The surfaces of some of the wool fibres used in this study were chemically modified to improve their alkali resistance and reinforcing properties. The flexural strengths and failure characteristics of the composites, determined on bar-shaped samples by a three-point test method, show an approximately 40 % improvement over the unreinforced matrix and graceful failure, unlike the unreinforced matrix that displays ceramic-like brittle fracture. Interaction between the sulphide linkages of the wool and the aluminosilicate matrix produces a blue-green colour in the wool, shown by UV–visible and IR spectroscopy to be related to the formation of the sulpho-aluminosilicate compound sodalite. The thermal behaviour of these composites was studied by thermogravimetric analysis, and scanning electron microscopy was used to study the fibre-matrix interface.  相似文献   
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The inhibitor of apoptosis (IAP) family of antiapoptotic genes, originally discovered in baculovirus, exists in animals ranging from insects to humans. Here, we investigated the ability of IAPs to suppress cell death in both a neuronal model of apoptosis and excitotoxicity. Cerebellar granule neurons undergo apoptosis when switched from 25 to 5 mM potassium, and excitotoxic cell death in response to glutamate. We examined the endogenous expression of four members of the IAP family, X chromosome-linked IAP (XIAP), rat IAP1 (RIAP1), RIAP2, and neuronal apoptosis inhibitory protein (NAIP), by semiquantitative reverse PCR and immunoblot analysis in cultured cerebellar granule neurons. Cerebellar granule neurons express significant levels of RIAP2 mRNA and protein, but expression of RIAP1, NAIP, and XIAP was not detected. RIAP2 mRNA content and protein levels did not change when cells were switched from 25 to 5 mM potassium. To determine whether ectopic expression of IAP influenced neuronal survival after potassium withdrawal or glutamate exposure, we used recombinant adenoviral vectors to target XIAP, human IAP1 (HIAP1), HIAP2, and NAIP into cerebellar granule neurons. We demonstrate that forced expression of IAPs efficiently blocked potassium withdrawal-induced N-acetyl-Asp-Glu-Val-Asp-specific caspase activity and reduced DNA fragmentation. However, neurons were only protected from apoptosis up to 24 h after potassium withdrawal, but not at later time points, suggesting that IAPs delay but do not block apoptosis in cerebellar granule neurons. In contrast, treatment with 100 microM or 1 mM glutamate did not induce caspase activity and adenoviral-mediated expression of IAPs had no influence on subsequent excitotoxic cell death.  相似文献   
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This article reviews the scientific literature in several areas important to the delivery of palliative care: multicultural issues, education, comprehensive outcome measures and ethics. Most of the research can be classified as fundamental rather than intervention research according to the Cancer Control Framework of the National Cancer Institute of Canada. Desired outcomes of interventions are most often defined from the health care professional's perspective but need to be defined from the patient's perspective. In areas such as multicultural issues and the effect of the volunteer on the patient, there is almost no research. The complexity of studying the best way to deliver palliative care would benefit from the input of colleagues who have experience addressing these issues in other patient populations.  相似文献   
29.
Archival material from primary and metastatic renal clear cell carcinomas of 25 patients was studied by comparative genomic hybridization. Copy number changes of entire chromosomes or chromosomal subregions were detected in 22 primary and 21 metastatic tumors. Copy number changes affected the following chromosomes in at least 20% of the 25 primary tumors (minimal common region given in parentheses): gains were noted for chromosomes 1 (1q21-->q23), 5 (5q31-->q34), 7 (7p), 8 (8q), 16 (16p), 17 (17q12-->qter), 19, and 22 (22q12-->qter); losses were revealed for chromosomes 3 (3p21-->pter), 8 (8p23-->pter), 14(14q21-->qter), and Y. The same chromosomal regions that were involved in primary renal clear cell carcinomas were also found in the respective metastatic tumors but with strikingly different frequencies for a few regions. Metastatic tumors showed a significantly higher frequency of complete or partial gains of the long arm of chromosome 1, in particular at 1q21-->q23 than primary tumors (16 cases versus 6 cases; P < 0.005). These data suggest a correlation of metastatic events in renal clear cell carcinomas with an increase in the copy number of genes located at 1q, in particular at 1q21-->q23. In contrast, the entire or partial loss of the short arm of chromosome 3 was significantly less frequent in metastatic tumors (8 cases versus 15 cases; P < 0.025). The validity of 1q and 3p copy number changes detected by comparative genomic hybridization was confirmed by interphase cytogenetics with region-specific yeast artificial chromosomes to paraffin-embedded tumor tissue sections.  相似文献   
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