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LS Wafelman BH Pollock J Kreutzer DS Richards AA Hutchison 《Canadian Metallurgical Quarterly》1999,75(2):73-81
Prognostic factors for survival of 62 fetuses and neonates with nonimmune hydrops fetalis (NIHF) were studied retrospectively. Twenty-eight infants survived >/=28 days which is 45% for all fetuses and newborns diagnosed with NIHF and 61% for liveborns with unresolved NIHF. Univariate analysis identified that mortality was associated with the presence of >/=2 serous cavity effusions and a need for chest compressions at birth. Multivariate logistic regression analysis confirmed that the presence of >/=2 serous cavity effusions was significantly associated with mortality from NIHF <28 days after birth [OR = 48.2 (CI 3.6, 662.9) (p < 0.004)]. We conclude that, compared to published cases from the 1970s and early 1980s, survival of liveborns with NIHF seems improved. The decrease in stillbirths is more notable. The severity of hydrops at birth is the key determinant for survival. 相似文献
105.
D. M. Lewis M. F. Lambert M. D. Burch J. D. Brookes 《Canadian Metallurgical Quarterly》2010,136(9):642-650
Full-scale field acoustic Doppler velocimeter measurements of the radial, axial, and tangential flow components were undertaken in a large-diameter turbulent swirling jet generated by a raft-mounted axial flow-mixing propeller discharging through a draft tube during isothermal and stratified conditions. The results were compared with classical jet theory and showed significant differences in the zone of flow establishment though similar behavior in the zone where established flow was found. It was concluded that the efflux from the axial flow-mixing propeller could not be described adequately by conventional jet theory due to the jet size and swirling characteristics. 相似文献
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Stuart Burch 《Landscape Research》2013,38(1):141-152
In some parts of Europe, stone wall field boundaries pervade agricultural landscapes, yet despite their prominence there has been very little research into field boundary walls anywhere. However, these anthropogenic features within cultural landscapes may offer insights into current debates on ‘novel’ ecosystems because of their artifice, their longevity in the landscape particularly in remote or exposed regions, and their morphology. In a review of the available, published literature in Europe, it was found that no publications exist that examine or illustrate specific ecological characteristics of field boundary stone walls, despite this longevity. Using examples from Ireland, where these structures are locally abundant, this paper aims first to draw attention to the poorly representative literature on this topic, and thus stimulate research that will detail the potential ecological characteristics of these ancient forms of field boundary. It then briefly explores the potential for these walls to be considered as ‘novel’ ecosystems within current debates on the issue. 相似文献
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SA Gould EE Moore FA Moore JB Haenel JM Burch H Sehgal L Sehgal R DeWoskin GS Moss 《Canadian Metallurgical Quarterly》1997,43(2):325-31; discussion 331-2
We have previously documented the safety of 1 unit (50 gram) of human polymerized hemoglobin (Poly SFH-P) in healthy volunteers. This report describes the first patient trial to assess the therapeutic benefit of Poly SFH-P in acute blood loss. Thirty-nine patients received 1 (n = 14), 2 (n = 2), 3 (n = 15), or 6 (n = 8) units of Poly SFH-P instead of red cells as part of their blood replacement after trauma and urgent surgery. There were no safety issues related to the infusion of Poly SFH-P. The plasma hemoglobin concentration ([Hb]) after the infusion of 6 units (300 gram) of Poly SFH-P was 4.8 +/- 0.8 g/dL (mean +/- SD). Although the red cell [Hb] fell to 2.9 +/- 1.2 g/dL, the total [Hb] was maintained at 7.5 +/- 1.2 g/dL. Poly SFH-P maintained total [Hb], despite the marked fall in red cell [Hb] due to blood loss. The utilization of O2 (extraction ratio) was 27 +/- 16% from the red cells and 37 +/- 13% from the Poly SFH-P. Twenty-three patients (59%) avoided allogeneic transfusions during the first 24 hours after blood loss. Poly SFH-P effectively loads and unloads O2 and maintains total hemoglobin in lieu of red cells after acute blood loss, thereby reducing allogeneic transfusions. Poly SFH-P seems to be a clinically useful blood substitute. 相似文献
110.
Polygalacturonase-inhibiting proteins (PGIPs) with different specificities are expressed in Phaseolus vulgaris 总被引:2,自引:0,他引:2
A Desiderio B Aracri F Leckie B Mattei G Salvi H Tigelaar JS Van Roekel DC Baulcombe LS Melchers G De Lorenzo F Cervone 《Canadian Metallurgical Quarterly》1997,10(7):852-860
The pgip-1 gene of Phaseolus vulgaris, encoding a polygalacturonase-inhibiting protein (PGIP), PGIP-1 (P. Toubart, A. Desiderio, G. Salvi, F. Cervone, L. Daroda, G. De Lorenzo, C. Bergmann, A. G. Darvill, and P. Albersheim, Plant J. 2:367-373, 1992), was expressed under control of the cauliflower mosaic virus 35S promoter in tomato plants via Agrobacterium tumefaciens-mediated transformation. Transgenic tomato plants with different expression levels of PGIP-1 were used in infection experiments with the pathogenic fungi Fusarium oxysporum f. sp. lycopersici, Botrytis cinerea, and Alternaria solani. No evident enhanced resistance, compared with the resistance of untransformed plants, was observed. The pgip-1 gene was also transiently expressed in Nicotiana benthamiana with potato virus X (PVX) as a vector. PGIP-1 purified from transgenic tomatoes and PGIP-1 in crude protein extracts of PVX-infected N. benthamiana plants were tested with several fungal polygalacturonases (PGs). PGIP-1 from both plant sources exhibited a specificity different from that of PGIP purified from P. vulgaris (bulk bean PGIP). Notably, PGIP-1 was unable to interact with a homogeneous PG from Fusarium moniliforme, as determined by surface plasmon resonance analysis, while the bulk bean PGIP interacted with and inhibited this enzyme. Moreover, PGIP-1 expressed in tomato and N. benthamiana had only a limited capacity to inhibit crude PG preparations from F. oxysporum f. sp. lycopersici, B. cinerea, and A. solani. Differential affinity chromatography was used to separate PGIP proteins present in P. vulgaris extracts. A PGIP-A with specificity similar to that of PGIP-1 was separated from a PGIP-B able to interact with both Aspergillus niger and F. moniliforme PGs. Our data show that PGIPs with different specificities are expressed in P. vulgaris and that the high-level expression of one member (pgip-1) of the PGIP gene family in transgenic plants is not sufficient to confer general, enhanced resistance to fungi. 相似文献