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排序方式: 共有1241条查询结果,搜索用时 15 毫秒
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Charles L. Bennett Sumimasa Nagai Andrew C. Bennett Shamia Hoque Chadi Nabhan Martin W. Schoen William J. Hrushesky Stefano Luminari Paul Ray Paul R. Yarnold Bart Witherspoon Josh Riente Laura Bobolts John Brusk Rebecca Tombleson Kevin Knopf Marc Fishman Y. Tony Yang Kenneth R. Carson Benjamin Djulbegovic John Restaino James O. Armitage Oliver A. Sartor 《The oncologist》2021,26(8):e1418-e1426
105.
Jimmy Espinoza Roberto Romero Juan Pedro Kusanovic Francesca Gotsch Offer Erez Wesley Lee Luís F. Gonalves Mary Lou Schoen Sonia S. Hassan 《Journal of ultrasound in medicine》2007,26(9):1181-8; quiz 1189-90
OBJECTIVE: Conotruncal anomalies represent one fifth of all congenital heart defects (CHDs) detected in the fetus. However, the spatial relationship of the great vessels is incorrectly defined in about 20% of these cases. The sagittal view of the ductal arch is considered a standard ultrasonographic view in fetal echocardiography and can be easily visualized using 4-dimensional (4D) ultrasonography. This study was designed to determine the role of this ultrasonographic plane for the prenatal diagnosis of conotruncal anomalies. METHODS: We reviewed 4D volume data sets, acquired with the spatiotemporal image correlation technique, from fetuses with and without confirmed conotruncal anomalies. The visualization rate of the sagittal view of the ductal arch was compared among groups using standardized multiplanar views. RESULTS: This study included 183 volume data sets from fetuses in the following groups: (1) normal echocardiographic findings (n = 130); (2) conotruncal anomalies (n = 18); and (3) other CHDs (n = 35). Volumes of poor image quality were excluded from analysis (8.2% [15/183]). The visualization rate of the sagittal view of the ductal arch was significantly lower in fetuses with conotruncal anomalies (5.6% [1/18]) than that in fetuses without abnormalities (93.1% [108/116]) and that in fetuses with other CHDs (79.4% [27/34]; P < .01). Absence of visualization of the sagittal view of the ductal arch was associated with a likelihood ratio of 9.44 (95% confidence interval, 5.8-15.5) to have conotruncal anomalies. CONCLUSIONS: The sagittal view of the ductal arch may play an important role in the screening and prenatal diagnosis of conotruncal anomalies in 4D ultrasonography. 相似文献
106.
Moog R Zeiler T Heuft HG Stephan B Fischer EG Kretschmer V Rödel-Spieker R Strasser E Zingsem J 《Transfusion》2003,43(10):1502-1502
107.
M Braun V Gliech A Boscheri S Schoen G Gahn H Reichmann M Haass R Schraeder R H Strasser 《European heart journal》2004,25(5):424-430
AIMS: Interventional PFO closure has previously been reported to reduce the risk for recurrent thromboembolic events. The aim of the present study was to evaluate three different occluder systems in respect to (a) the safety and practicability and (b) the mid-term risk of recurrent thromboembolic events. METHODS AND RESULTS: Since 08/98 until 12/02, 307 consecutive patients (138 women, 169 men, mean age 43 years) with a symptomatic PFO underwent PFO closure using the PFO-Star ( n=177), Amplatzer PFO occluder ( n=69) and CardioSeal/Starflex ( n=61 ). Implantation was successful in all patients. Periinterventional complications occurred in 9 patients (5x ST-segment elevations, 1x arteriovenous fistula, 2x TIA, 1x device dislodgement). All of them were reversible and not associated with a specific type of device. During the median follow-up of 24 months (25/75th percentiles: 14/37 months), the annual risk of recurrence was 0.6% for TIA, 0% for stroke and 0.2% for peripheral embolism (PFO-Star: 0.8%, Amplatzer PFO occluder: 0.7% and CardioSeal/Starflex: 1.0%). CONCLUSION: Interventional PFO closure appears to be safe and a promising technique in symptomatic PFO patients with a low incidence of periinterventional complications and recurrent thromboembolic events using three different devices (PFO-Star, Amplatzer PFO occluder or the CardioSeal/Starflex). 相似文献
108.
Hagner-Holler S Schoen A Erker W Marden JH Rupprecht R Decker H Burmester T 《Proceedings of the National Academy of Sciences of the United States of America》2004,101(3):871-874
Insects possess an elaborate tracheal system that enables transport of gaseous oxygen from the atmosphere directly to the inner organs. Therefore, the presence of specialized oxygen-transport proteins in the circulatory system of insects has been considered generally unnecessary. Here, we show for the first time, to our knowledge, the presence of an ancestral and functional hemocyanin (Hc) in an insect. In the hemolymph of nymphs and adults of the stonefly Perla marginata, a hexameric Hc was identified, which consists of two distinct subunit types of 659 and 655 amino acids. P. marginata Hc displays cooperative oxygen binding with a moderately high oxygen affinity [(half-saturation pressure, P(50) approximately 8 torr (1 torr = 133 Pa)]. No evidence was found for the presence of Hcs in the more evolutionarily advanced holometabolan insects, suggesting that this type of respiratory protein was lost later in insect evolution. However, our results demonstrate that, in contrast to the accepted paradigm, certain basal insects have retained an ancestral blood-based mechanism of gas exchange. 相似文献
109.
The regulation of hemopoiesis in long-term bone marrow cultures. II. Stimulation and inhibition of stem cell proliferation 总被引:6,自引:1,他引:6
The isolation of a DNA synthesis inhibitor (NBME fraction IV) and stimulator (RBME fraction III) specific for the hemopoietic stem cell (CFU-s) from freshly isolated normal adult and regenerating murine bone marrow, respectively, has been well documented. We have utilized long- term liquid bone marrow cultures in a further analysis of the role of these factors in the regulation of CFU-s proliferation. Our results show that shortly after feeding, at a time when the cultured CFU-s are actively proliferating, high levels of the hemopoietic stem cell proliferation stimulator fraction III can be isolated from the culture medium. In contrast, the presence of essentially noncycling CFU-s found in cultures fed 8-10 days previously correlates with high levels of the hemopoietic stem cell inhibitor fraction IV. These results suggest that a certain balance between these factors determines CFU-s proliferation in the long-term cultures. In support of this, DNA synthesis in actively cycling CFU-s in the long-term cultures is inhibited for at least 3 days by the addition of excess NBME fraction IV (inhibitor). Furthermore, DNA synthesis in noncycling cultured CFU-s is stimulated for at least 5 days by the addition of RBME fraction III (stimulator). 相似文献
110.
Preparation of factor IX deficient human plasma by immunoaffinity chromatography using a monoclonal antibody 总被引:1,自引:0,他引:1
Goodall AH; Kemble G; O'Brien DP; Rawlings E; Rotblat F; Russell GC; Janossy G; Tuddenham EG 《Blood》1982,59(3):664-670
A murine hybridoma clone is described that grows continuously in culture and produces a monoclonal antibody we have called Royal Free Monoclonal Antibody to factor IX No. 1 (RFF-IX/1). This has high affinity for a coagulation site on factor IX. RFF-IX/1 immobilised on sepharose can be used to deplete factor IX from normal human plasma. This immunoaffinity depleted plasma is indistinguishable from severe Christmas disease plasma and can be used as the substrate in a one stage coagulation assay for factor IX. The affinity column has high capacity and can be regenerated so that large scale production from normal plasma of factor IX deficient plasma as a diagnostic reagent is now feasible. 相似文献