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排序方式: 共有1294条查询结果,搜索用时 62 毫秒
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Clinical significance, prevalence, and natural history of thrombocytopenia in pregnancy-induced hypertension 总被引:2,自引:0,他引:2
R Romero M Mazor C J Lockwood M Emamian K P Belanger J C Hobbins T Duffy 《American journal of perinatology》1989,6(1):32-38
The purpose of this study was to establish the prevalence and clinical significance of thrombocytopenia in pregnancy-induced hypertension (PIH). Thrombocytopenia, defined as a platelet count less than 100,000/mm3 was found in 11.6% of all patients with PIH. Logistic regression analysis was used to assess the relative contribution of thrombocytopenia, proteinuria, and the degree of hypertension to maternal and perinatal outcome. Thrombocytopenia was the principal contributor to the occurrence of abdominal pain, liver dysfunction, the presence of schistocytes in the peripheral smear, proteinuria, fetal distress, and the requirement for blood transfusions. Thrombocytopenia was also associated with a higher incidence of preterm delivery and intrauterine growth retardation. The nadir platelet count occurred within 48 hours of delivery in 56.7% (21 of 37) of cases. The median number of days for recovery of the thrombocytopenia was 2.0 days (range, 0 to 8 days). In five patients thrombocytopenia preceded the clinical manifestations of PIH. We conclude that thrombocytopenia is an independent and important risk factor for the occurrence of maternal and perinatal complications in PIH. 相似文献
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N Radunovic C J Lockwood M Alvarez D Nastic R L Berkowitz 《American journal of obstetrics and gynecology》1992,167(3):740-744
OBJECTIVE: Endogenous opiates may play a role in both fetal physiologic functions and the adaptation to intrauterine stress. However, our understanding of this role is hampered by an absence of data on circulating levels of these substances during fetal life. STUDY DESIGN: We measured serum beta-endorphin values with a radioimmunoassay in 81 paired fetal and maternal blood samples and 24 neonatal cord specimens. The former samples were uneventfully obtained from uncomplicated pregnancies between 18 and 39 weeks of gestation at the time of cordocentesis for prenatal diagnosis. RESULTS: Mean fetal beta-endorphin concentrations were significantly lower than beta-endorphin values from neonates (90.5 pg/ml [+/- 59.4] vs 228.4 pg/ml [+/- 166.2]; p less than 0.001), but significantly higher than mean maternal values (70.5 pg/ml [+/- 48.8]; p less than 0.02). Although fetal beta-endorphin levels decreased between 18 and 28 weeks' gestation, the correlation between fetal beta-endorphin values and gestational age was not significant (r = -0.193; p = 0.07). However, fetal beta-endorphin concentrations were significantly correlated with maternal values (Spearman's rank r = 0.47; p less than 0.001). CONCLUSION: These findings suggest that delivery or fetal adaptation to an extrauterine environment is associated with significant increases in beta-endorphin release. Moreover, although the fetal pituitary may be the primary source of circulating fetal beta-endorphin, a maternal or placental contribution cannot be excluded. Our data identify a physiologic range for fetal beta-endorphin concentrations. 相似文献
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R J Stiller S Soberman A Turetsky C Lockwood R Haddad 《American journal of obstetrics and gynecology》1988,158(1):172-173
A pregnancy complicated by dyspnea was associated with agenesis of the right pulmonary artery. The clinical characteristics of the agenesis of the pulmonary artery along with the differential diagnosis from pulmonary embolus are discussed. 相似文献
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Messer RL Lockwood PE Wataha JC Lewis JB Norris S Bouillaguet S 《The Journal of prosthetic dentistry》2003,90(5):452-458
STATEMENT OF PROBLEM: The biocompatibility of new dental ceramics has not been assessed with the same scrutiny as has been applied to alloys and composites. Yet, the biocompatibility of ceramics is critical to the long-term success of dental prostheses because ceramics are in close contact with oral tissues for extended periods. MATERIAL AND METHODS: Five dental ceramics (2 traditional feldspathic veneer porcelains [Vita Omega and Duceragold], 2 lithium disilicate pressable materials [Stylepress and Empress-2], and a pressable leucite-based material [Empress-1]) were tested for their ability to alter cellular mitochondrial dehydrogenase activity after fabrication using a tetrazolium assay, after aging for 2 weeks in a biologic solution and after post-aging polishing with either a fine diamond or diamond polishing paste. Cellular responses were compared with polytetrafluoroethylene controls (analysis of variance, Tukey pairwise post-hoc comparison, alpha=.05). RESULTS: The feldspathic porcelains caused only mild (<25% of controls) mitochondrial suppression regardless of aging or polishing. The pressable leucite-based material initially caused a 5% stimulation (not significant) of mitochondrial activity, which decreased significantly (P<.05) by 30% with aging to levels comparable to the feldspathic porcelains, and did not change with polishing. Both lithium disilicate materials caused an initial suppression of mitochondrial activity that decreased significantly with aging, but Empress-2 was severely cytotoxic initially (<20% of controls, P<.01), and became more cytotoxic again after polishing. Stylepress was less cytotoxic initially (85% of controls, not significant) and did not become cytotoxic again after polishing. CONCLUSIONS: Dental ceramics are not equivalent in their in vitro biologic effects, even within the same class of material, and biologic safety should not be assumed. Most ceramics caused only mild in vitro suppression of cell function to levels that would be acceptable on the basis of standards used to evaluate alloys and composites. However, 1 Li-disilicate material (Empress-2) exhibited cytotoxicity that would not be deemed biologically acceptable on the basis of prevailing empirical standards for dental alloys and composites. 相似文献
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Heterotopic pregnancy, or simultaneous intrauterine and extrauterine gestation, is a relatively rare condition. However, induced ovulation and assisted reproductive technologies have markedly increased the incidence of this condition. In this article, a case of heterotopic pregnancy after in vitro fertilization and embryo transfer is presented in which the viable cervical pregnancy was treated by transvaginal ultrasound-guided puncture and injection of potassium chloride in conjunction with methotrexate at week 6 of gestation. At week 12 of gestation, the intrauterine gestation was viable and complete resorption of the cervical pregnancy had occurred. At week 30 of gestation, a healthy baby was delivered by Caesarian section after prelabour rupture of membranes. 相似文献