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排序方式: 共有581条查询结果,搜索用时 15 毫秒
61.
Xi Zheng Wang Yi Bo Wen Xiao Ping Shang Yi He Wang Yan Wei Li Tian Fang Li Shou Lin Li Jing Yang Yan Jin Liu Xiao Ping Lou Wei Zhou Xing Li Jian Jiang Zhang Cui Ping Song Cecilie Siggaard Jorgensen Soren Rittig Stuart Bauer Giovanni Mosiello Qing Wei Wang Jian Guo Wen 《Neurourology and urodynamics》2019,38(5):1423-1429
62.
Emanuel Gaziano MD Cecilie Gaziano PhD Debra Brandt RT RDMA 《American journal of obstetrics and gynecology》1998,178(6):1359-1367
OBJECTIVE: Our purpose was to study fetal growth and blood flow distribution in diamniotic monochorionic compared with dizygotic (diamniotic dichorionic) twins by use of Doppler velocimetry of the umbilical artery and middle cerebral artery. STUDY DESIGN: Study candidates were divided into group A, consisting of 33 pairs (66 fetuses) of diamniotic monochorionic twins, and group B, 50 pairs (100 fetuses) of diamniotic dichorionic twins. Diamniotic monochorionic placentation was confirmed by microscopic placental examination for group A. Diamniotic dichorionic placentation was ensured for group B by selecting only twins with different-sex pairs (dizygotic twins). Targeted ultrasonography with biometry was performed in each twin, and Doppler recordings of the umbilical artery and middle cerebral artery were obtained. Waveforms were analyzed and the systolic/diastolic ratio, the resistance index, and a measure of blood flow redistribution (brain-sparing effect), the cerebral/placental ratio, was calculated for each fetus. Growth status at birth was assessed by the number of small-for-gestational-age infants (≤10th percentile), low-birth-weight infants (≤25th percentile), and percent of growth discordance between twins. Intertwin differences were assessed by Δ values (value of larger twin minus value of smaller twin). RESULTS: Diamniotic monochorionic compared with dizygotic twins demonstrated a significantly greater probability of blood flow redistribution. For the study population as a whole, the brain-sparing effect was noted in 67% of small-for-gestational-age babies and only 7% of non-small-for-gestational-age infants (p ≤ 0.001). For the diamniotic monochorionic pregnancies blood flow redistribution occurred in 6 of 10 small-for-gestational-age infants (60%) and 6 of 46 non-small-for-gestational-age infants (13%). In the diamniotic monochorionic group small-for-gestational-age compared with non-small-for-gestational-age infants were more likely to show blood flow redistribution, which was the result of significantly decreased resistance in the middle cerebral artery and significantly increased resistance in the umbilical artery. Small-for-gestational-age infants (≤10th percentile) occurred much less frequently in the dizygotic group. Two of two small-for-gestational-age infants in the dizygotic group showed blood flow redistribution. Although the extremes of birth weight were more common in the diamniotic monochorionic group, both groups had relatively large numbers of small babies with birth weights in the lower 25th percentile (50.0% for diamniotic monochorionic and 44.0% for dizygotic twins, not significant). However, 42.3% (11/26) of diamniotic monochorionic twins who were in the low-birth-weight group showed blood flow redistribution compared with only 3.3% (1/30) whose birth weights were ≥25th percentile (p ≤ 0.001). In the dizygotic twins 10% of lower-birth-weight infants redistributed blood flow compared with 1% in the higher-birth-weight group, a nonsignificant difference. Diamniotic monochorionic compared with dizygotic twins were delivered earlier (32.9 weeks vs 34.8 weeks, p ≤ 0.001), were smaller (1832 gm vs 2304 gm, p ≤ 0.001), showed higher birth weight discordance (29.8% vs 14%, p ≤ 0.05), and had greater numbers (19.7% vs 2.3%, p ≤ 0.01) of infants at ≤10th percentile birth weight. CONCLUSIONS: Diamniotic monochorionic twins from the lower-birth-weight groups more often show blood flow redistribution compared with dizygotic twins of similar low birth weights. Placental vascular connections and the attendant hemodynamic changes in the fetuses of diamniotic monochorionic twins probably account for this difference. Brain-sparing events occur commonly without clinical twin transfusion syndrome in this group. These findings have implications for management. (Am J Obstet Gynecol 1998;178:1359-67.) 相似文献
63.
Frank J E Vajda Terrence O'Brien Alison Hitchcock Janet Graham Cecilie Lander Mervyn Eadie 《Journal of clinical neuroscience》2008,15(1):29-35
The aim of this study was to determine how valid 68 first-trimester pregnancies of untreated epileptic women would prove as an internal control group for investigating foetal malformation rates in 709 simultaneously collected antiepileptic drug-exposed pregnancies in an Australian register of pregnancies in epileptic women. We carried out comparisons of values for parameters relating to personal details, obstetric aspects, and epilepsies prior to and during pregnancy in the drug-exposed and drug-unexposed pregnancies, with observations on subpopulations within the drug-unexposed group. Statistically significant (p<0.05) differences existed for only seven of more than 50 parameters compared. None of these seven parameters had a statistically significant influence on foetal malformation rates in the whole dataset. In 23 of the 65 epileptic pregnancies unexposed to antiepileptic drugs, therapy had been ceased shortly prior to pregnancy and was often resumed after the first trimester. In the remaining 42, therapy had been ceased earlier, often despite continuing seizures. Planned withdrawal of therapy did not appear to produce additional hazards for mothers and foetuses in the former subgroup. In the data collection studied, there did not appear to be evidence of statistically significant differences between untreated pregnancies and treated epileptic pregnancies that would be likely to invalidate the former group as an internal control for the latter, at least when assessing foetal malformation rates. 相似文献
64.
65.
66.
Fred Fack Heidi Espedal Olivier Keunen Anna Golebiewska Nina Obad Patrick N. Harter Michel Mittelbronn Oliver Bähr Astrid Weyerbrock Linda Stuhr Hrvoje Miletic Per Ø. Sakariassen Daniel Stieber Cecilie B. Rygh Morten Lund-Johansen Liang Zheng Eyal Gottlieb Simone P. Niclou Rolf Bjerkvig 《Acta neuropathologica》2015,129(1):115-131
67.
68.
Øie E Vinge LE Andersen GØ Yndestad A Krobert KA Sandberg C Ahmed MS Haug T Levy FO Skomedal T Attramadal H 《Journal of molecular and cellular cardiology》2005,38(1):145-151
Adrenomedullin (AM) is a potent vasorelaxing peptide with natriuretic and diuretic actions. Recent data indicate that AM may function as an endogenous regulator of cardiac function. We investigated to what extent AM, the AM receptor subtypes, and AM receptor-associated proteins were regulated in cardiomyocytes and non-cardiomyocytes of rats with congestive heart failure (CHF), and whether such regulation was paralleled by corresponding alterations of functional responses to AM. Cardiomyocytes and non-cardiomyocytes were isolated from myocardial tissue of rats 7 days after induction of myocardial infarction or sham operation. AM immunoreactivity was found in cardiomyocytes, endothelial cells, and fibroblasts. Robust increase of AM mRNA levels was observed both in the cardiomyocytes and in the non-cardiomyocytes of CHF rats compared to that of sham-operated rats (2.7-fold and 3.7-fold, respectively, P <0.05). Fairly high mRNA levels and immunoreactivity against the AM receptor chaperone receptor activity-modifying protein-2 (RAMP2) were also detected in the cardiomyocytes and non-cardiomyocytes. However, induction of RAMP2 mRNA expression was restricted to cardiomyocytes (1.8-fold increase in cardiomyocytes from CHF rats vs. sham rats; P <0.05). In contrast, very low levels of RAMP3 mRNA were observed. RAMP3 mRNA levels, however, were elevated in both cardiomyocytes and non-cardiomyocytes from CHF rats (6.5-fold and 2.4-fold increase vs. sham rats, respectively; P <0.05). Parallel increases of specific AM receptor binding sites and of AM-stimulated adenylyl cyclase activities were observed in failing cardiomyocytes compared to cardiomyocytes from sham rats (fivefold and sixfold increase, respectively; P <0.05). Thus, this study demonstrates that AM mRNA levels, AM receptor binding sites, and AM-stimulated adenylyl cyclase activities are increased in cardiomyocytes from failing rat hearts. Furthermore, our data suggest that induction of RAMP2 and RAMP3 contributes to the increased responsiveness to AM in failing cardiomyocytes. 相似文献
69.
Marte Schrumpf Heiberg Wenche Koldingsnes Knut Mikkelsen Erik Rødevand Cecilie Kaufmann Petter Mowinckel Tore K. Kvien 《Arthritis care & research》2008,59(2):234-240