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891.
U Milkau E Berdermann B Berthier P Bouissou C Cerruti A Demeyer E Eckert D Guinet KD Hildenbrand J Hubele G Imme P Kreutz A Kühmichel GJ Kunde S Leray P Lhénoret R Lucas U Lynen C Mazur WF Müller C Ng CH Pinkenburg J Pochodzalla HJ Rabe G Raciti M Ribrag H Sann H Stelzer E Tomasi W Trautmann R Trockel R Wada 《Canadian Metallurgical Quarterly》1991,44(4):R1242-R1245
892.
893.
M F al-Hinnawi J Barbenel I A al-Qurainy G N Dutton 《Proceedings of the Institution of Mechanical Engineers. Part H, Journal of engineering in medicine》1991,205(2):101-108
The active and passive behaviour of the extraocular muscles can be investigated by measuring the force that must be applied to rotate the eyeball when the muscles are relaxed (the forced duction test) or the force required to maintain the eyeball stationary while the contralateral eye follows a moving target (the force generation test). Apparatus and test procedures for carrying out both tests are described. Normal values and confidence intervals for the tests have been obtained and the results of muscle entrapment and palsy illustrated. 相似文献
894.
GJ Pankhurst CA Bennett SB Easterbrook-Smith 《Canadian Metallurgical Quarterly》1998,37(14):4823-4830
Clusterin is a highly conserved mammalian glycoprotein which has been predicted to contain heparin-binding sites. We tested this prediction by studying the interactions between heparin and clusterin using ELISA and heparin affinity chromatography methodologies. Two forms of biotinylated heparin were used in ELISA: heparin which had been directly biotinylated with a biotin-N-hydroxysuccinimide ester and heparin which had been activated using epichlorohydrin and 1,6-diaminohexane prior to biotinylation. Both gave dose-dependent increases in ELISA signal with increasing concentrations of biotinylated heparin, with the latter giving signals an order of magnitude greater than the former. There was a dose-dependent increase in the ELISA signal from bound biotinylated heparin with increasing concentrations of plate-bound clusterin. The apparent affinity constant for binding of biotinylated heparin to plate-bound clusterin at pH 6.0 was estimated as 0.06 +/- 0.02 microM. Unlabeled heparin blocked the binding of biotinylated heparin to clusterin over a concentration range similar to that of the binding of biotinylated heparin to plate-bound clusterin. The binding of biotinylated heparin to clusterin was independent of the presence or absence of Ca2+. The binding of biotinylated heparin to plate-bound clusterin increased with decreasing pH over the range 5.5-8.0 and was characterized by an apparent pKa of 6.9. Clusterin in human serum bound to heparin-Sepharose at pH 6.0 but not at pH 7.4. Dot-blot experiments showed that one of the polypeptide chains of clusterin which had been reduced and alkylated under denaturing conditions bound to heparin-Sepharose. This chain was identified as the alpha chain from its N-terminal amino acid sequence. 相似文献
895.
GJ Fraenkel 《Canadian Metallurgical Quarterly》1998,2(6):422-424
Many deaths among hospital survivors of acute myocardial infarction are due to sustained ventricular tachycardia and ventricular fibrillation. This has prompted the evaluation of prophylactic antiarrhythmic drugs and devices. Although it is widely agreed that antiarrhythmic treatment is useful, it is not certain which therapy provides optimal results. Increasing recognition of the efficacy of amiodarone has prompted the design of several trials of the drug. This paper focuses on primary prophylactic antiarrythmic therapy in the post-infarction setting and particularly on recent amiodarone trials. 相似文献
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Local anesthetic partition coefficients correlate with drug potencies in vitro, but in vivo data have not always complimented in vitro results. Despite extensive studies on intrathecal anesthetic action, whether there is correlation between the partition coefficient and local anesthetic potency has not been addressed. Mice (n = 150) were randomly allocated into 15 groups. Intrathecal injections of etidocaine (E), tetracaine (T), bupivacaine (B), lidocaine (L), or procaine (P) were administered and analgetic effect was measured using tail-flick (TF) test. Concentration-response regressions were constructed for each drug; EC50 values were calculated and compared at 95% confidence intervals. The EC50 values between E (0.017%), T (0.019%), and B (0.012%) were not significantly variant. The EC50 of L (0.098%) and P (0.229%) were significantly different from each other and from E, T, and B. The EC50 values were converted to ED50 in nmols. Relative anesthetic potency, defined as the inverse value of ED50 of drug was 23:16:15:2.4:1 for B, E, T, L, and P, respectively. ED50 showed high correlation (R = 0.978) with partition coefficients of local anesthetics. This study implies that the partition coefficient is a predictor of intrathecal local anesthetic potency. We suggest that the mouse model is reliable for evaluation of intrathecal local anesthetic action. 相似文献