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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
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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
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LS Sheldon JT Keever JM Roberds JB Beach JN Morgan 《Canadian Metallurgical Quarterly》1997,7(1):37-59
Dietary uptake may be a significant pathway of exposure to contaminants. As such, dietary exposure assessments should be considered an important part of the total exposure assessment process. The objective of this work was to develop reliable methods that are applicable to a wide range of base/neutral and carbamate-type pesticides in duplicate diet samples collected as part of dietary exposure assessment studies. The resulting method needed to be sensitive to concentrations below 1 ng/g, accurate and precise, and as simple and cost effective as possible. As a first step, information was gathered on current methods for measuring pesticides in foods. Although the literature methods could serve as a starting point, few had been applied to duplicate diet samples and detection limits were generally high (10 to 100 ng/g). Experimental work was performed to evaluate individual extraction, cleanup, and analysis procedures; link the most promising procedures into analysis methods; and generate performance data on the final method. The final method used Soxhlet extraction with solvent partitioning and gel permeation chromatography cleanup. Gas chromatography/mass spectrometry was used for the analysis of base/neutral pesticides. High performance liquid chromatography analysis was used for the analysis of carbamate pesticides. Results of performance testing showed good accuracy (recovery > 70%), precision (% RSD < 25%), and sensitivity (method detection limits < 1.0 ng/g) for most pesticides targeted for study. 相似文献