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排序方式: 共有739条查询结果,搜索用时 15 毫秒
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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
3.
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
4.
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
5.
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
6.
7.
M Marty P Pouillart S Scholl J P Droz M Azab N Brion E Pujade-Lauraine B Paule D Paes J Bons 《The New England journal of medicine》1990,322(12):816-821
To compare ondansetron (GR 38032F), a 5-hydroxytryptamine3-receptor antagonist, with metoclopramide in the prophylaxis of acute cisplatin-induced emesis, we conducted a double-blind crossover study in 97 patients scheduled to receive cisplatin (80 to 100 mg per square meter of body-surface area) for treatment of cancer. None had received chemotherapy before this trial. Among the 76 patients who satisfactorily completed both parts of the study, complete or nearly complete control of emesis (i.e., no episodes of emesis occurred, or only one or two) was achieved in 57 of 76 treatments (75 percent) with ondansetron and in 32 of 76 treatments (42 percent) with metoclopramide (P less than 0.001). Ondansetron was also more effective in controlling acute nausea, as assessed with a visual-analogue scale (P = 0.019) or a graded scale (P = 0.024). There was a significant preference among patients for ondansetron (55 vs. 26 percent; P = 0.006). Dystonic reactions were observed during three treatments with metoclopramide; both agents were otherwise well tolerated. We conclude that ondansetron is more effective than metoclopramide in the control of cisplatin-induced nausea and vomiting, and that this suggests that serotonin is an important mediator of this side effect. 相似文献
8.
9.
H. Hirsch H. Scholl K. G. Paschke H. Schmid-Schönbein 《Pflügers Archiv : European journal of physiology》1968,301(4):334-343
Zusammenfassung Die corticale Gleichspannung wurde an isolierten Hundeköpfen von der Konvexität des Gehirns (Gyrus lateralis) gegen Nase (Knochenoberfläche des os frontale) bei kompletter und inkompletter Gehirnischämie gemessen.Während kompletter Gehirnischämie verschiebt sich die Gleichspannung nach einer initialen Positivierung, die 1,5–2,75 min nach Ischämiebeginn ein Maximum von 1,5–2 mV erreicht, in negativer Richtung. Diese Negativierung erreicht 3–8 min nach Ischämiebeginn einen steady state von im Mittel 6,5 mV. Nach Ende der kompletten Gehirnischämie kommt es nach einer kurzfristigen Positivierung zu einer länger dauernden Negativierung.Bei inkompletter Gehirnischämie kommt es zu einer Negativierung der Gleichspannung, wenn der Blutdruck auf 80–40 mm Hg abgefallen ist. Es wird vermutet, daß die Negativierung bei der für das Gehirn kritischen Blutdruckhöhe beginnt.Auszugsweise vorgetragen auf der 31. Tagung der Deutschen Physiologischen Gesellschaft Würzburg 1966 [Pflügers Arch. ges. Physiol. 289, R 5 (1966)]. 相似文献
10.
Raymond S McDermott Frédéric Beuvon Marc Pauly Claude Pallud Anne Vincent-Salomon Veronique Mosseri Pierre Pouillart Susy M Scholl 《Pathobiology》2002,70(6):324-332
AIMS: Cancer cells frequently express antigens capable of being recognized by the host immune system; however, any resultant immune response is often ineffective. This may be related in part to tumor-induced defects in antigen presentation. We screened for dendritic cell infiltration, tumor MHC II expression and associated lymphocytic reaction in the context of three established breast tumor antigens. METHODS: Forty primary breast tumors were evaluated by immunohistochemical techniques for expression of her2/neu, p53, and MUC1 and MHC class II molecules. Twenty-five samples were further analyzed for p53 mutations by PCR-SSCP analysis and DNA sequencing. The phenotype of tumor-infiltrating inflammatory cells was evaluated using the following markers: CD1a, MHC Class II, CD3, CD45, and CD45RO. RESULTS: Tumors with p53 mutations and overexpression, but not her2/neu or MUC1 overexpressing tumors, more frequently harbored marked CD1a+ dendritic cell infiltrates. An overall correlation between CD1a+ cell infiltrates and HLA class II expression on tumor cells (p = 0.0008) was also observed and these tumors had greater CD45RO+ lymphocytic infiltrates. CONCLUSIONS: In breast cancer, p53 mutations may present a more visible signal to the immune system and hence provide a better target for immunotherapy. Infiltrating CD1a positive cells are associated with a more dense tumor lymphocytic infiltrate and tumor cell expression of MHC II molecules. 相似文献