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排序方式: 共有773条查询结果,搜索用时 15 毫秒
71.
A Lorentz ; A Jendrissek ; KU Eckardt ; M Schipplick ; PM Osswald ; A Kurtz 《Transfusion》1991,31(7):650-654
The variations in plasma erythropoietin (EPO) concentration during preoperative deposit of autologous blood were studied in 12 patients (8 men, 4 women). Four donations were scheduled at weekly intervals. A predonation hemoglobin concentration of 11 g per dL (110 g/L) was required. Hemoglobin concentration decreased from 14.3 +/- 1.1 g per dL (143 +/- 11 g/L) (mean +/- SD) before the first donation to 11.7 +/- 0.7 g per dL (117 +/- 7 g/L) on Day 22 (p less than or equal to 0.0001). Reticulocyte counts increased from a median of 31,800 (range, 4900-95,000) per microL (median, 32 x 10(9)/L [range, 5-95 x 10(9)/L]) to 93,800 (16,800-194,900) per microL (median, 94 x 10(9)/L [range, 17-195 x 10(9)/L]) on Day 28 (p less than or equal to 0.01). Plasma EPO concentration was 17.8 +/- 5.1 mU per mL prior to the first donation and displayed a small and transient peak after each donation. A sustained elevation followed each peak. Although plasma EPO concentration differed significantly from the baseline value after the first donation, only the peak concentrations after the second (35.5 +/- 15.5 mU/mL), third (38.0 +/- 14.5 mU/mL), and fourth (36.1 +/- 11.0 mU/mL) donations exceeded the normal range. The moderate, biphasic increase in plasma EPO concentration and the moderate increase in erythropoiesis suggest two strategies in autologous blood donation that should be investigated with respect to efficiency and safety: 1) more aggressive donation schemes, which reduce donation intervals and/or the minimum hemoglobin concentration and 2) the administration of recombinant human EPO. 相似文献
72.
Transmission of hepatitis G virus in patients with angioedema treated with steam-heated plasma concentrates of C1 inhibitor 总被引:2,自引:0,他引:2
F De Filippi; R Castelli ; M Cicardi ; R Soffredini ; MG Rumi ; E Silini ; PM Mannucci ; M Colombo 《Transfusion》1998,38(3):307-311
BACKGROUND: Hepatitis G virus (HGV) is a blood-borne flavivirus that may cause acute and chronic transfusion-transmitted infections. Patients with complement component 1 (C1) inhibitor (C1-INH) deficiency may acquire blood-borne infections through infusion of plasma concentrates. STUDY DESIGN AND METHODS: Serum samples from 84 patients with C1-INH deficiency (19 who received unmodified C1-INH concentrates, 23 who received steam-heated concentrates, and 42 untreated patients) were tested for HGV RNA and hepatitis C virus (HCV) RNA by a nested polymerase chain reaction (PCR). The samples were also tested for antibodies to the E2 envelope protein of HGV (anti-HGV) and to HCV with enzyme-linked immunosorbent assays. RESULTS: Nine (11%) patients had serum HGV RNA; that is, 7 (17%) of 42 patients previously treated with C1-INH concentrates and 2 of 42 previously untreated patients. HGV RNA was as common in the 19 patients treated with unmodified concentrates as in the 23 given steam-heated concentrates (16 vs. 17%, p = 0.60). Anti-HGV was more common among the recipients of unmodified concentrates than among those given steam-heated concentrates (26 vs. 0%, p = 0.014). HCV RNA was more frequently detected in treated patients than in untreated patients (33 vs. 7%, p = 0.005) and in the 19 recipients of unmodified concentrates than in the 23 treated with steam-heated concentrates (58 vs. 16%, p = 0.003). Only one HGV RNA- seropositive patient had elevated serum aminotransferase activity, compared to 11 with HCV RNA. CONCLUSION: HGV was transmitted by both unmodified and steam-heated concentrates, but it caused persistent viremia in a minority of the cases and was rarely associated with liver disease. 相似文献
73.
BACKGROUND: Individuals with epilepsy or seizure disorders are restricted from donating blood because of concern that they are prone to adverse donor reactions such as syncope and convulsions. A study evaluating whether that concern is warranted is reported. STUDY DESIGN AND METHODS: During a 2-year period beginning in 1987, blood donors in Maryland with a history of seizures were actively recruited by the American Red Cross. Adverse donor reactions were classified as "slight", indicating dizziness and nausea without loss of consciousness; "moderate," denoting syncope; and "severe," indicating convulsive syncope. RESULTS: There were 329,143 satisfactory blood donations; 613 individuals reporting a history of seizures donated blood a total of 723 times. Among donors with seizures, 186 (35.7%) were taking antiepileptic medication, and 61 (8.4%) had had one or more seizures in the preceding year. Individuals with seizures had a low incidence of adverse reactions (3.34%). Although this incidence was slightly higher than that in the entire population (2.24%), the difference was not significant. In particular, the risk of syncope with or without convulsive activity was low for people with seizures (0.21%) and not significantly greater than that in other donors (0.28%). CONCLUSION: Individuals with seizures or epilepsy are not at greater risk for adverse reactions after blood donation, and major restrictions on their participation as blood donors are not warranted. 相似文献
74.
75.
Jean‐Philippe Brandel MD Craig A. Heath MD Mark W. Head PhD Etienne Levavasseur PhD Richard Knight MD Jean‐Louis Laplanche PharmD PhD Jan PM. Langeveld PhD James W. Ironside MD Jean‐Jacques Hauw MD Jan Mackenzie Annick Alpérovitch MD Robert G. Will MD Stéphane Haïk MD PhD 《Annals of neurology》2009,65(3):249-256
76.
Review of the Lynch syndrome: history, molecular genetics, screening, differential diagnosis, and medicolegal ramifications 总被引:1,自引:0,他引:1
Platelets have a central role in the development of arterial thrombosis and subsequent cardiovascular events. An appreciation of this complex process has made antiplatelet therapy the cornerstone of cardiovascular disease management. However, numerous patients will experience a recurrent atherothrombotic vascular event despite adequate antiplatelet therapy. Individual differences in the rate of platelet activation and reactivity markedly influence normal hemostasis and the pathological outcome of thrombosis. Such an individual variability is largely determined by environmental and genetic factors. These are known to either hamper platelets' response to agonists, and thereby mimic the pharmacological modulation of platelet function or mask therapy effect and sensitize platelets. In this article, we reviewed the antiplatelet mechanisms of aspirin and clopidogrel and the possible role of different polymorphisms, which may affect the efficacy of antiplatelet therapy. Heterogeneity in the way patients respond to aspirin and clopidogrel may in part reflect variation in cyclooxygenase (COX)-1, COX-2, glycoprotein (GP) Ib alpha, GP Ia/IIa, GP IIb/IIIa, UGT1A6*2, P2Y1 , P2Y12 , CYP2C9, CYP3A4 and CYP3A5 genotypes. 相似文献
77.
78.
C. Boulanger NA Flavahan ZS Katusic K. Komori AA Vos and PM Vanhoutte MD Director 《Fundamental & clinical pharmacology》1990,4(5):525-538
Experiments were designed to determine the effect of CRL 41034, a buflomedil analogue, on the adrenergic responsiveness of canine veins. Rings of saphenous vein (without endothelium) were suspended for isometric tension recording in modified Krebs-Ringer bicarbonate solution at 37 degrees C. CRL 41034 produced a concentration-dependent inhibition of the contractions evoked by the alpha adrenergic agonists norepinephrine, phenylephrine and UK 14304 which was insensitive to the blockade of neuronal uptake by cocaine. CRL 41034 was more potent in inhibiting the concentration-dependent contractions evoked by UK 14304 than those by phenylephrine and the antagonism it caused against the response to UK 14304 fulfilled the criteria for competitivity. CRL 41034, at 10(-5) M significantly depressed, and at 10(-4) M abolished the contractions induced by electrical stimulation of the adrenergic nerves and those evoked by the indirect sympathomimetic amine tyramine. Strips of canine saphenous vein were superfused after incubation with [3H] norepinephrine. During sympathetic nerve activation, CRL 41304 increased the stimulation-evoked overflow of [3H] norepinephrine and 3-methoxy-4-dihydroxyphenylglycol; in the presence of rauwolscine the compound only increased the stimulation-evoked overflow of 3,4-dihydroxyphenylglycol. These experiments suggest that the major vascular effects of CRL 41034 in canine veins are blockade of alpha 2-adrenoceptors on vascular smooth muscle, and inhibition of prejunctional alpha 2-adrenoceptors on adrenergic nerve endings. 相似文献
79.
Summary— Oxidative modifications of low density lipoproteins (LDL) are now recognised as one of the major processes in atherogenesis. Various drugs, as well as a number of natural products, have been proposed to inhibit such processes. Among the naturally-occurring constituents of plants which appear to possess antioxidant activity are polyphenolic compounds such as flavonoids. The aqueous extract of Vaccinium myrtillus is rich in such molecules. In this report, we describe the in vitro antioxidative potential of this extract on human LDL. The copper-induced oxidative modification of these lipoproteins was assessed using 1) measurement of oxidative resistance as determined by the lag-phase preceding conjugated diene formation; 2) quantification of the amount of lipoperoxides and thiobarbituric acid-reactive substances generated, and measurement of the modification in the net negative electrical charge of the lipoproteins, over a 7-hour time course experiment. Trace amounts of V myrtillus extract (15 to 20 μg/mL) induce statistically significant changes in the oxidation behaviour of LDL, which include 1) prolongation of the lag-phase of conjugated diene production ( P < 0.01); 2) reduction in the formation of lipoperoxides and of thiobarbituric acid-reactive substances up to 7 hours and especially between 1 and 5 hours ( P < 0.01); and 3) inhibition of modification in the net negative charge of LDL. These results demonstrate that V myrtillus extract exerts potent protective action on LDL particles during in vitro copper-mediated oxidation. Calculation of IC50 values indicates that, on a molar basis, this extract may indeed be more potent than either ascorbic acid or butylated hydroxytoluene in the protection of LDL particles from oxidative stress. 相似文献
80.
Nicole PM Ezendam Anke Oenema Petra M van de Looij-Jansen Johannes Brug 《BMC public health》2007,7(1):324