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971.
H. Klüter I. Dörges E. Maass T. Wagner H. Bartels H. Kirchner 《Annals of hematology》1996,73(2):85-89
Random-donor platelet concentrates (PC) prepared from pooled buffy coats have recently been described as an alternative method
for platelet preparation. We evaluated such PCs in the clinical setting compared with a standard PC from platelet apheresis.
PCs were prepared either from pools of buffy coats (BC-PC) or from single donors (SD-PC) with the cell separator CS-3000 plus.
PCs were stored for up to 5 days before transfusion. We compared fresh PC (day 1) with stored (day 2–3) and long-stored PC
(day 4–5). For analysis, platelet increment in the recipient was determined immediately and 16–22 h (mean 20 h) after transfusion,
corrected for total body area and transfused platelets (CCI). A total of 316 PCs were administered to 36 thrombocytopenic
patients suffering from various hematological disorders. Patients with detectable HLA or platelet-specific antibodies or splenomegaly
were excluded from the study. Mean platelet content of the PC was 262×109 for BC-PC and 251×109 for SD-PC. The 20-h CCI after transfusion of fresh PC was slightly higher with BC-PC than with SD-PC (14.5 versus 11.9;p=0.19), but values did not differ significantly between the two types of PC on any day of storage. For BC-PC, 20-h CCI decreased
with further storage by 30% (10.2;p=0.02). For SD-PC a decrease by 9% was not significant. In conclusion, platelet concentrates prepared from pools of buffy
coats showed excellent transfusion results when administered fresh, but storage decreased the CCI by 30%. No significant difference
from PCs from plateletpheresis was observed on any day of storage. Both types of platelet concentrates were capable of sufficient
platelet increment even when stored for up to 5 days.
Received: 28 December 1995 / Accepted: 14 May 1996 相似文献
972.
A. Schlüter 《Der Radiologe》1998,38(5):450-453
Ohne Zusammenfassung 相似文献
973.
The effects of left- and right-sided hemispheric brain infarction on variability in circadian blood pressure and cardiovascular measures were investigated in 35 patients to test for asymmetry of the sympathetic consequences of stroke. No significant differences regarding age, size of infarction or extent and frequency of damage to the insular cortex could be detected between the two groups. Patients with right-sided infarction showed a significantly reduced circadian blood pressure variability [diastolic: -1% (95% CI -4 to 1) vs -6% (-9 to -2);P < 0.05] and a higher frequency of nocturnal blood pressure increase (47% vs 35%;P < 0.05) as compared with patients with left-sided infarction. Right-sided infarction was also associated with higher serum noradrenaline concentrations [546 pg/ml (95% CI 415–677) vs 405 pg/ml (266–544);P < 0.05], and ECG more frequently showed QT prolongation (53% vs 35%;P < 0.05) and cardiac arrhythmias (67% vs 20%;P < 0.005). However, irrespective of the hemisphere damaged, patients with insular infarction showed the most pronounced changes of these parameters. In addition, two patients with right-sided strokes (13%) involving the insula, but none with a left-sided infarction, developed myocardial infarction. These findings suggest lateralization of sympathetic activation with right-sided dominance for sympathetic effects following hemispheric stroke.Supported by the Friedrich-Schiedel-Stiftung 相似文献
974.
975.
Evaluation of late cardiotoxicity with pulsed Doppler echocardiography in patients treated for Hodgkin's disease 总被引:2,自引:0,他引:2
Ernst-Dietrich Kreuser Heinz Völler Christian Behles Klaus Schröder Alexander Uhrig Angela Besserer Eckhard Thiel 《British journal of haematology》1993,84(4):615-622
Summary. The impact of valvular, myocardial and pericardial abnormalities on cardiac haemodynamics in patients treated for Hodgkin's disease with COPP/ABVD with and without mediastinal irradiation was determined in 49 patients 2–10 years after induction therapy. Diagnostic procedures to evaluate cardiac function consisted of history, physical examination, exercise bicycle stress test, M-mode two-dimensional and pulsed Doppler echocardiography. No patient reported symptoms related to cardiomyopathy, and only one of the 49 had evidence of coronary heart disease. Pericardial thickening was seen on echocardiograms in 19/49 patients (38.8%), valvular thickening in 21/49 (42·9%), and reduced fractional shortening in 9/49 (18·4%). The Doppler-derived mean E and A (±SD) of transmitral flow were 0·75 ± 0·14 m/s and 0·56 ± 0·09 m/s, respectively, in patients receiving chemotherapy and 0·81 ± 0.19 m/s and 0·63 ± 0·20 m/s in those with additional mediastinal irradiation. There was no statistically significant difference between mean E and A in transmitral flow in patients treated for Hodgkin's disease and control subjects. Furthermore, the transtricuspid and hepatic vein flow velocities did not differ significantly. Although the present study demonstrates high frequencies of pericardial and valvular thickening in patients treated for Hodgkin's disease with the COPP/ABVD regimen with or without mediastinal irradiation, it showed no impact on cardiac flow velocities. The abnormalities might thus be of minor clinical relevance in these patients. 相似文献
976.
977.
G. Hege-Scheuing K. Michaelsen A. Bühler J. Kustermann W. Seeling 《Der Anaesthesist》1995,44(5):351-358
Previous studies investigating the peripheral action of locally instilled morphine after arthroscopic knee surgery found evidence for an analgesic effect. Follow-up studies have lead to conflicting results.We used patient-controlled analgesia (PCA) to test the analgesic potency of intraarticular morphine. Methods. Patients undergoing arthroscopic knee surgery under general anaesthesia received, after written informed consent and in double-blind and randomised manner, 1?mg morphine diluted in 10?ml saline either intraarticularly or intravenously at the end of the surgical procedure. A control injection of 10?ml saline was given at the other site. The pain intensity on a visual analogue scale (VAS) and the cumulative morphine consumption were recorded at 1, 2, 3, 4, 6, 8 and 24?h after the end of general anaesthesia. Statistics: Wilcoxon rank sum test with P<0.05. Results. A total of 59?patients were included in the study; 29 received morphine intraarticularly (verum group), 30 intravenously (control group). There was no difference in gender, age, duration of arthroscopy or anaesthesia. There were more than 60% diagnostic arthroscopies in both groups; other types of surgery were comparable, with the exception of cruciate band repair procedures only in the control group. We found no difference in morphine consumption or pain intensity between the two groups throughout the study period. Median overall consumption of morphine after 24?h was 14?mg in the verum group and 15?mg in the control group, with wide interindividual variation. Pain intensities were remarkably low. The peak pain intensity of both groups was found at 1?h postoperatively, with median 16/100 on the VAS in both groups. Blinding was robust. Conclusion. We found no reduction in postoperative morphine supplementation after 1?mg morphine intraarticularly compared to 1?mg intravenously given at the end of knee arthroscopies. There were also no differences in pain intensities on a VAS. We conclude that titration of postoperative pain with a morphine-filled PCA pump was unable to show a difference in analgesic potency between intraarticular and intravenous morphine. 相似文献
978.
The mode of action and the structure of a herbicide in complex with its target: binding of activated hydantocidin to the feedback regulation site of adenylosuccinate synthetase. 总被引:4,自引:0,他引:4
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R Fonné-Pfister P Chemla E Ward M Girardet K E Kreuz R B Honzatko H J Fromm H P Sch?r M G Grütter S W Cowan-Jacob 《Proceedings of the National Academy of Sciences of the United States of America》1996,93(18):9431-9436
(+)-Hydantocidin, a recently discovered natural spironucleoside with potent herbicidal activity, is shown to be a proherbicide that, after phosphorylation at the 5' position, inhibits adenylosuccinate synthetase, an enzyme involved in de novo purine synthesis. The mode of binding of hydantocidin 5'-monophosphate to the target enzyme was analyzed by determining the crystal structure of the enzyme-inhibitor complex at 2.6-A resolution. It was found that adenylosuccinate synthetase binds the phosphorylated compound in the same fashion as it does adenosine 5'-monophosphate, the natural feedback regulator of this enzyme. This work provides the first crystal structure of a herbicide-target complex reported to date. 相似文献
979.
Backspatter from experimental close-range shots to the head 总被引:1,自引:0,他引:1
B. Karger R. Nüsse B. Brinkmann G. Schroeder S. Wüstenbecker 《International journal of legal medicine》1996,109(2):66-74
Backspatter is the ejection of biological material from a gunshot entrance wound against the line of fire. This phenomenon was investigated experimentally in transverse gunshots to the heads of calves (n = 9) using two types of 9 mm Parabellum ammunition from shooting distances of 0–10 cm. The resulting bloodstains were documented on white paper placed horizontally 60 cm below the impact site. In this report the analysis was restricted to stains with a diameter > 0.5 mm. Backspatter was documented after every gunshot. The number of stains varied from 31–324 per gunshot and appeared to be independent of the shooting distance. The maximum distance droplets travelled varied from 72–119 cm. The majority of droplets accumulated between 0 and 50 cm. The number of droplets and the distances travelled should be higher in man for anatomical reasons. The direction a single droplet can take comprises every possible angle between the most tangential ones to the skin surface. This resulted in a semi-circle of 180° covered with stains. Skin ruptures of the entrance wound were not observed. The succession of events was documented on high speed film and started with the recoil of the firearm, immediately followed by a blow-out effect of the skin. Large droplets exited approximately 0.7–4 ms after the bullet impacted the skin. The calculated minimum initial velocity of these droplets was 13–61 m/s. Backspatter from gunshots to the head likely is caused by the hot gases expanding subcutaneously and by cavitation-related intracranial overpressure and tail splashing. In three out of nine gunshots, secondary backspatter additionally occurred as a result of droplets produced by a stream of blood from the entrance wound impacting the paper surface. 相似文献
980.