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1.
Haemodilution induces a hypercoagulable state 总被引:10,自引:3,他引:7
It has been suggested that haemodilution with saline may increase whole
blood coagulation. This study was conducted in two parts. First, we
investigated the effect of in vitro dilution of blood with saline on whole
blood coagulation as measured by the thrombelastogram (TEG). Blood (4 ml)
was diluted with 0.9% saline 1 ml and coagulation compared with that of an
undiluted control specimen obtained concurrently from the same subject. In
the second part, the study was repeated using a modified gelatin colloidal
solution (Haemaccel) as the diluent. The r time, k time and r + k time were
decreased relative to control in both diluent groups. The alpha angles were
increased compared with control in both groups while maximum amplitude was
unchanged in the Haemaccel diluted group. We conclude that haemodilution
per se increases the coagulability of whole blood in vitro, but that saline
haemodilution has a more marked effect on final clot strength.
相似文献
2.
J J Viljoen L S Wessels 《South African journal of surgery. Suid-Afrikaanse tydskrif vir chirurgie》1990,28(4):133-137
Over an 8-year period (1982-1989) 43 patients with subacute and chronic extradural haematomas were treated. The clinical picture of the patients, computed tomography (CT) as well as operative findings and prognosis were evaluated. The radiological picture as seen on CT was correlated with the time interval elapsing between initial trauma and surgery. Operative findings are discussed and the terms 'subacute' and 'chronic' are defined. 相似文献
3.
4.
Widespread epiphyseal stippling was demonstrated radiologically during the early months of life in 7 children with acrodysostosis. This finding, which does not seem to have been previously documented in this disorder, is important in the differential diagnosis. 相似文献
5.
A 20-year-old woman with Beckwith-Wiedemann syndrome (BWS) was ultrasonographically appraised at intervals during her pregnancy. Unequivocal evidence for a diagnosis of BWS was obtained in the fetus and this was confirmed postnatally. Early ultrasound diagnosis enabled appropriate genetic counselling to be given; neonatal complications, such as hypoglycaemic episodes, were prevented. 相似文献
6.
Alpha-glucosidase activity and sperm motility 总被引:2,自引:0,他引:2
We correlated the activity of alpha-glucosidase in seminal plasma with the motility and differential motility of sperm. Significant positive correlations were found between the alpha-glucosidase activity and both motility and the percentage sperm with good forward progression. This supports the use of alpha-glucosidase in semen as a marker of epididymal function and specifically of the development of motility. 相似文献
7.
Joost B. M. M. van Bree Anne V. Baljet Anton van Geyt Albertus G. de Boer Meindert Danhof Douwe D. Breimer 《Journal of pharmacokinetics and pharmacodynamics》1989,17(4):441-462
The unit impulse response theory has been adapted to characterize the transport profile of drugs into the central nervous system (CNS). From the obtained input function, the cumulative plasma volume (V) cleared by transport into the CNS in time can be calculated. Simulation studies demonstrated that transport governed by passive diffusion resulted in a linear relationship between V and time, while the slope of the line, the blood- brain barrier (BBB) clearance, proved to be an adequate and model independent parameter to characterize drug transport into the CNS. The error in the result of the numerical procedure could be limited to less than 10% of the theoretically predicted value. Superposition of 5 or 10% random noise on simulated data did not result in significant differences between the calculated and theoretically predicted clearance values. Simulations of carrier-mediated transport resulted in nonlinear transport curves; the degree of nonlinearity, and thus the detectability, was dependent on the initial degree of saturation of the system, the rate of desaturation, as caused by drug elimination processes and the noise level on the data. In vivoexperiments in the rat were performed, using atenolol, acetaminophen, and antipyrine as model drugs. Linear transport relationships were obtained for all drugs, indicating that transport was dependent on passive diffusion or a low affinity carrier system. BBB- clearance values were 7±1 l/min for atenolol, 63±7 ul/min for acetaminiphen and 316±25 l/min for antipyrine. These experiments validate the applicability of the presented technique in in vivostudies. 相似文献
8.
van Hoogdalem Ewoud J. Heijligers-Feijen Cornelia D. de Boer Albertus G. Verhoef J. Coos Breimer Douwe D. 《Pharmaceutical research》1989,6(1):91-95
The stability of the neuroleptic peptide des-enkephalin--endorphin (DEE; Org 5878) in the rectal lumen and the rectal bioavailability of DEE were investigated in conscious rats. Furthermore, the influence of peptidase inhibition, peptidase saturation, and absorption enhancement on DEE bio-availability were evaluated. Na2EDTA (0.25%, w/v) prolonged the degradation half-life of DEE in the ligated colon from 33 ± 7 to 93 ± 45 min. Without adjuvant, tritium-labeled DEE was absorbed from the rat rectum to a very low extent (0–4%). After administration of an excess of unlabeled DEE or with Na2EDTA, comparable results were obtained. The medium-chain glyceride preparation MGK markedly enhanced the rectal DEE bioavailability, up to 8–20%, which was further increased to 10–44% by coadministration of Na2EDTA. No substantial influence of varying the rectal delivery rate was observed. The results suggest that absorption enhancement and enzyme inhibition both are essential for effective increase of rectal peptide bioavailability. 相似文献
9.
We describe an 18-month-old boy with Costello syndrome (CS) with proven partial growth hormone (GH) deficiency and hypoglycemic episodes. The hypoglycemia is deemed to be due to cortisol deficiency. This report represents the second published case of cortisol deficiency in the CS. A brief review of the endocrine disturbances in the syndrome is provided. We highlight the need for careful endocrinological evaluation of individuals with CS. 相似文献
10.
Attention to Color: An Analysis of Selection, Controlled Search, and Motor Activation, Using Event-Related Potentials 总被引:3,自引:0,他引:3
Albertus A. Wijers Gijsbertus Mulder Tsunetaka Okita Lambertus J.M. Mulder Marten K. Scheffers 《Psychophysiology》1989,26(1):89-109
In this study the organization of information processing in a selective search task was examined by analyzing event-related potentials. This task consisted of searching for target letters in a relevant (attended) color. The ERPs revealed two different effects of attention: an early occipital negativity (+/- 150 ms) reflecting feature-specific attention, and a later, central N2b component (+/- 240 ms) reflecting covert orienting of attention. A later, prolonged negativity (search-related negativity) (+/- 300 ms), maximal at Cz, was related to controlled search to letters in the attended color. Detection of relevant targets resulted in a parietal P3b component. Depending on stimulus presentation conditions an earlier response to both attended and unattended targets was found: an N2 component (+/- 250 ms). In these same conditions, C'3-C'4 asymmetries (Corrected Motor Asymmetries--CMA) suggested motor activation at +/- 300 ms, in the same time range as search-related negativity. It was argued that N2 and CMA suggest the existence of a preattentive target detection system, operating in parallel with a slower serial attentive system, as reflected by N2b and search negativity. 相似文献