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排序方式: 共有901条查询结果,搜索用时 31 毫秒
1.
MR compatibility of Guglielmi detachable coils 总被引:6,自引:0,他引:6
2.
Adverse reaction to intravenous gadoteridol 总被引:1,自引:0,他引:1
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4.
Anemia vs iron deficiency: increased risk of preterm delivery in a prospective study. 总被引:6,自引:0,他引:6
T O Scholl M L Hediger R L Fischer J W Shearer 《The American journal of clinical nutrition》1992,55(5):985-988
Using criteria from the Centers for Disease Control, anemia and iron-deficiency anemia (anemia with serum ferritin concentrations less than 12 micrograms/L) were assessed in greater than 800 inner-city gravidas at entry to prenatal care. Iron-deficiency anemia was associated with significantly lower energy and iron intakes early in pregnancy and a lower mean corpuscular volume. The odds of low birth weight were tripled and of preterm delivery more than doubled with iron deficiency, but were not increased with anemia from other causes. When vaginal bleeding at or before entry to care accompanied anemia, the odds of a preterm delivery were increased fivefold for iron-deficiency anemia and doubled for other anemias. Inadequate pregnancy weight gain was more prevalent among those with iron-deficiency anemia and in those with anemias of other etiologies. The prevalence of iron-deficiency anemia (3.5%), however, was lower than anticipated for an inner-city, minority population in whom most anemias had been attributed clinically to iron deficiency. 相似文献
5.
J G Byrne R F Appleyard C C Lee G S Couper F G Scholl R G Laurence L H Cohn 《The Journal of thoracic and cardiovascular surgery》1992,103(1):66-71; discussion 71-2
Open-chest sheep underwent 90 minutes' occlusion of the diagonal branch of the left anterior descending coronary artery, followed by vented cardiopulmonary bypass. After 30 minutes of cardioplegic arrest, simulating distal anastomoses, the occlusion on the coronary artery branch was released. Controlled reperfusion (40 to 50 mm Hg, 135 to 150 ml/min) for the first 20 minutes was delivered at the aortic root with either unmodified whole blood (control, n = 7) or blood passed through leukocyte filters (filters, n = 7). Serial measurements were made during 3 additional hours reperfusion off cardiopulmonary bypass. During ischemia, the major determinants of infarct size, which include area at risk, collateral myocardial blood flow, and rate-pressure product were not significantly different between groups. Overall, during reperfusion, mean left ventricular stroke work index in the filter group was greater than in the control group (28.7 +/- 5.8 versus 12.6 +/- 6.4 x 10(3) erg/gm, p less than 0.05), as was mean rate of rise of left ventricular pressure (1900 +/- 260 versus 1348 +/- 279 mm Hg/sec, p less than 0.05). Myocardial blood flow to the area at risk at 3 1/2 hours of reperfusion in the filter group was also significantly better than in the control group (0.57 +/- 0.15 versus 0.27 +/- 0.05 ml/min/gm, p less than 0.05), as was necrotic area as a percentage of area at risk (40% +/- 6% versus 70% +/- 5%, p less than 0.05). These results demonstrate amelioration of myocardial stunning and the no-reflow phenomenon, as well as decreased infarct size. We conclude that controlled reperfusion with leukocyte-depleted blood is superior to whole-blood reperfusion for the surgical treatment of acute regional ischemia. 相似文献
6.
Hanbing Lu Clara A Scholl Yantao Zuo Elliot A Stein Yihong Yang 《Magnetic resonance in medicine》2007,58(3):616-621
In cerebral blood volume (CBV)-weighted functional MRI (fMRI) employing superparamagnetic contrast agent, iron dose and blood oxygenation level dependent (BOLD) contamination are two important issues for experimental design and CBV quantification. Both BOLD and CBV-weighted fMRI are based upon the susceptibility effect, to which spin-echo and gradient-echo sequences have different sensitivities. In the present study, CBV-weighted fMRI was conducted using spin-echo and gradient-echo sequences at 9.4T by systematically changing the doses of contrast agent. Results suggest that BOLD contamination is a significant component in CBV-weighted fMRI at high field, particularly when relatively low dose of contrast agent is administered. A mathematical model was developed to quantify the extravascular (EV) BOLD effect. With a TE of 35 ms, the EV BOLD effect was estimated to account for 76+/-12% of the observed spin-echo fMRI signal at 9.4T. These data suggest that correcting BOLD effect may be necessary for accurately quantifying activation-induced CBV changes at high field. 相似文献
7.
8.
P. J. Flory V. Bühren Ch. Scholl und M. Potulski 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》1986,369(1):810
Zusammenfassung Bei den jährlich ca. 40 Motorradrennen, die in Deutschland für über 3000 Lizenzfahrer veranstaltet werden, stürzen jeweils 10% der Fahrer. Die Verletzungsschwerpunkte liegen im Schultergürtel-, Handgelenks- und Unterschenkel-Fußbereich. Normale Straßenmotorradfahrer verunfallen statistisch häufiger. Eine vergleichende Analyse zeigt für die Verletzungen der unteren Extremität einen höheren Anteil an komplizierten und offenen Frakturen. Das günstigere Abschneiden der Rennfahrer erklärt sich aus einer wesentlich besseren Unfallprevention. 相似文献
9.
The patellofemoral joint was imaged with magnetic resonance (MR) in the axial plane while the knee was positioned from 0 degrees to 32 degrees of flexion (nine positions). These multiple sequential images obtained within the early phases of flexion of the knee were viewed in a "cine-loop" format, producing a kinematic study that clearly demonstrated the relationship of the patella to the trochlear groove. Four healthy subjects and one patient with known bilateral subluxing patellae were studied. The preliminary results suggest that kinematic MR imaging of the patellofemoral joint is potentially useful for the evaluation of patellar tracking abnormalities. 相似文献