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OBJECTIVES: We have previously shown that the levels of circulatory fetal DNA are elevated in preeclampsia and that these increases correspond to disease severity. Several reports have indicated that increased levels of antiphospholipid (anti-PL) and anti-DNA antibodies may be associated with preeclampsia, in particular with the severe forms of the disorder. Since the release of cell-free DNA by the placenta is attributed to some form of cell death or damage and as anti-PL and anti-double-stranded DNA (dsDNA) antibodies have been proposed to lead to placental damage, we have studied the relationship between these parameters in preeclampsia. METHODS: Circulating fetal DNA levels in samples taken from pregnant women with mild (n = 12) or severe (n = 12) preeclampsia and from normal pregnant controls (n = 35) were quantified using a Taqman real-time Polymerase Chain Reaction (PCR) assay. The Anti-PL antibodies (IgG and IgM) were assayed by anticardiolipin ELISA and by commercial anti-beta2-Glycoprotein I (GPI) ELISA kits. Anti-dsDNA antibodies (IgG and IgM) were analyzed by a commercially available anti-dsDNA ELISA kit. RESULTS: No correlation could be drawn with the quantity of circulatory fetal DNA in the samples analyzed and corresponding anti-PL or anti-dsDNA antibody levels. Furthermore, no significant difference existed between the levels of these antibodies in the two study groups and the control cohort. CONCLUSION: Our data suggest that the mechanism leading to the increased release of cell-free circulatory DNA from the placenta does not involve trophoblast damage mediated by these agents. Our analysis also questions the reported involvement of anti-PL and anti-DNA antibodies in preeclampsia. 相似文献
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Background and Objective: Although the empirical characteristics of ArF excimer laser corneal ablation have been well documented, the exact ablation mechanisms are not well understood. The present paper reports a quantitative analysis of corneal ablation plumes using in situ time resolved laser light scattering and Raman spectroscopy. Study Design/Materials and Methods: Bovine corneas were used as the ArF excimer laser ablation targets. Light scattering data were recorded from the ablation plume as a function of height above the tissue surface and as function of delay time with respect to the ablative ArF laser pulse. Results: Raman spectra of the ablation plume allow identification of the particles as water. Mean plume particle diameters are found to decrease with height, while the particle volume fractions are relatively constant. The total volume of plume particles correlates well with the total volume of water in the ablated corneal tissue. Conclusion: The finding of a non-evolving plume composed of water spherules, combined with the excellent agreement between total volume of water in the plume and the content of water in the ablated corneal tissue, support the concept of photodecomposition or “cold ablation” for corneal tissue during ArF excimer laser ablation. © 1995 Wiley-Liss, Inc. 相似文献
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The role of oxygen supply in islet transplantation. 总被引:1,自引:0,他引:1
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Kim Hahn Le Quan Sang Jean-Luc Elghozi Philippe Meyer Marie-Aude Devynck 《Clinical and experimental pharmacology & physiology》1987,14(3):187-189
1. Plasma renin activity (PRA) and platelet cytosolic free calcium concentration ([Ca2+]i) were simultaneously determined in 18 untreated essential hypertensive subjects and 17 normotensive controls. A significant positive correlation was found between [Ca2+]i and PRA (slope = 42 nmol/l/ng/ml/h) in these 35 subjects. 2. Two determinations more than one week apart in nine subjects confirmed the parallel fluctuations of [Ca2+]i and PRA. A strict sodium restriction produced a progressive PRA elevation associated with a parallel rise in [Ca2+]i in one subject. 3. These results are consistent with the hypothesis that angiotensin II causes a concentration-dependent calcium mobilization. 相似文献
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We present a rare case of a 27-year-old man sustaining a bilateral fracture dislocation of the sacroiliac joints without
disruption of the anterior pelvis, following a fall from a height. Reconstructed images in the coronal plane and three-dimensional
CT images were invaluable in the diagnosis and assessment of this injury. 相似文献
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Miranda Jeanne James J. Gross Jacqueline B. Persons Judy Hahn 《Cognitive therapy and research》1998,22(4):363-376
Cognitive theory holds that dysfunctionalattitudes are important risk factors for depression.Critics have questioned this view, noting that, althoughdysfunctional attitudes are elevated in depression, they are not evident in vulnerable individualswho are asymptomatic. To deal with this criticism,Miranda and Persons (1988) have advanced the mood-statedependent hypothesis, which suggests that cognitive vulnerability factors are indeed present invulnerable individuals, but remain dormant untilactivated by negative mood. To test this hypothesis, 33women with and 67 women without histories of depression reported dysfunctional attitudes before andafter a film negative mood induction. As predicted,vulnerable subjects who reported increased negative moodreported increased dysfunctional attitudes.Unexpectedly, nonvulnerable subjects who reported increasednegative mood reported decreased dysfunctionalattitudes. These findings support the mood-statedependent hypothesis, and suggest that a deficit in theability to regulate negative emotions may be animportant feature of vulnerability todepression. 相似文献