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71.
The loss of available iodine from povidone-iodine solution stored in contact with two different polyetherpolyurethane foams was monitored as a function of time and temperature. Statistical evaluation of the results for the four temperatures studied [ambient (25 degrees), 30, 45 and 55 degrees C] indicated the chemical equivalence of the two foams as storage and delivery systems for povidone-iodine solution in terms of solution stability. In addition, application of a first-order kinetic model to the data produced an acceptable fit. An Arrhenius-type evaluation of the resulting rate constants yielded a linear relationship which was shown to be useful for predicting loss of available iodine under ambient temperature conditions of storage. 相似文献
72.
73.
Abstract: We describe the use of restriction analysis on PCR-amplified DNA for detecting all B*27 subtypes except B*2710 and B*2711 (i.e. from B*2701 to B*2709). After detecting B*27 by Sty I, double digestions consisting of Sty I plus another informative enzyme led to subtype assignment. We used mismatched primers to create restriction sites when necessary. The method avoids group-specific amplifications and other laborious optimization procedures. It was successfully tested on a panel of well characterized cell lines covering different B*27 subtypes. Then, we studied a group of 57 ankylosing spondyiitis patients and 746 controls from the south of Spain. B*27 showed a very strong association with the disease (OR=211.27, P=\0˜7). B*2702 and B*2705 distribution in controls (20% and 77.1%, respectively) differed from previously reported data in the Spanish population. We unexpectedly found the B*2707 allele in our population (one control). 相似文献
74.
C. T. Laurencin R. S. Cummings T. R. Jones L. Martin 《Journal of the National Medical Association》1998,90(12):779-781
Bony fusions involving the carpus have a much higher prevalence in blacks relative to whites. This article describes a case of lunotriquetral coalition fracture-dislocation in an African American. This lesion is best treated through open reduction and pin fixation. 相似文献
75.
Dmitri Artemov Zaver M. Bhujwalla Ross J. Maxwell John R. Griffiths Ian R. Judson Martin O. Leach Jerry D. Glickson 《Magnetic resonance in medicine》1995,34(3):338-342
The anticancer agent temozolomide labeled with 13C (8-Carbamoyl-3-13C-methylimidazo-[5,1-d]-1,2,3,5-tetrazin-4-(3H)-one), was noninvasively detected in subcutaneous RIF-1 tumors by a selective cross polarization 13C NMR method, at a field strength of 9.4T. Pharmacokinetics of the drug, at a dose of 150 mg/kg, were determined for intravenous and intraperitoneal modes of administration (three animals per mode). The half-life of the drug in the tumors was approximately 60 min. The uptake and clearance of the drug, however, varied significantly between individual hosts, for both modes of administration. These results demonstrate the feasibility of obtaining pharmacokinetics of anticancer agents for individual tumors without the need for a label that might modify drug activity (e.g., fluorine). The variability of the in vivo measurements, even within the same tumor model, demonstrates the necessity of directly monitoring the tumor to evaluate drug pharmacokinetics. 相似文献
76.
77.
Martin Klomp Peter M. Van den Bergh Frits J. H. Harinck 《Child & youth care forum》1997,26(5):343-355
In child and youth care in the Netherlands, systematic planning of treatment is more and more considered to be a condition
for effective and well founded treatment. Although workers are convinced of the benefits of treatment plans, treatment planning
is not yet a natural and integrated part of residential care. There are several pressure points. In this article a model of
treatment planning will be presented that contributes to an answer to these pressure points. The theoretical bases and the
practical implications of this model will be discussed. 相似文献
78.
79.
Characterization and isolation of SOB2, a human sperm protein with a potential role in oocyte membrane binding 总被引:2,自引:1,他引:1
Lefevre A; Martin Ruiz C; Chokomian S; Duquenne C; Finaz C 《Molecular human reproduction》1997,3(6):507-516
G12 monoclonal antibody (mAb), one of a library of constructed mAb directed
against human sperm proteins, was found by immunoperoxidase staining to
label the post-acrosomal and neck regions of fixed human cauda epididymal
and ejaculated spermatozoa. Epithelium and fluid of caput epididymis were
strongly labelled while there was no staining on testis and efferent ducts.
Western lot analysis revealed that G12 antibody reacted with proteins of
17.5, 18 and 19 kDa in human spermatozoa. This pattern seems to be specific
for mature human spermatozoa, as it has not been observed either in other
human tissues tested, or in spermatozoa from different animals. SOB2, the
corresponding protein, was isolated from NP40-extracted human spermatozoa
by using preparative electrophoresis, followed by isoelectrofocusing
according to its isoelectric point of 6.4 G12 Fab fragments strongly
inhibited binding of human spermatozoa to zona-free hamster oocytes (up to
86% inhibition at 200 micrograms/ml). Impairment of binding was dependent
on the concentration of purified G12 immunoglobulin (Ig)G1, and significant
even at 10 micrograms/ml. There was no inhibitory effect of G12 antibody on
sperm motility parameters or triggering of the acrosome reaction and it did
not inhibit binding to human zona pellucida. These results indicate that
SOB2 is likely to participate in membrane oocyte binding, and my be
potential candidate for the development of a contraceptive vaccine.
相似文献
80.
Voltage dependence of the pattern and frequency of discrete Ca2+ release events after brief repriming in frog skeletal muscle 下载免费PDF全文
Michael G. Klein Alain Lacampagne Martin F. Schneider 《Proceedings of the National Academy of Sciences of the United States of America》1997,94(20):11061-11066
Applying a brief repolarizing pre-pulse to a depolarized frog skeletal muscle fiber restores a small fraction of the transverse tubule membrane voltage sensors from the inactivated state. During a subsequent depolarizing test pulse we detected brief, highly localized elevations of myoplasmic Ca2+ concentration (Ca2+ “sparks”) initiated by restored voltage sensors in individual triads at all test pulse voltages. The latency histogram of these events gives the gating pattern of the sarcoplasmic reticulum (SR) calcium release channels controlled by the restored voltage sensors. Both event frequency and clustering of events near the start of the test pulse increase with test pulse depolarization. The macroscopic SR calcium release waveform, obtained from the spark latency histogram and the estimated open time of the channel or channels underlying a spark, exhibits an early peak and rapid marked decline during large depolarizations. For smaller depolarizations, the release waveform exhibits a smaller peak and a slower decline. However, the mean use time and mean amplitude of the individual sparks are quite similar at all test depolarizations and at all times during a given depolarization, indicating that the channel open times and conductances underlying sparks are essentially independent of voltage. Thus, the voltage dependence of SR Ca2+ release is due to changes in the frequency and pattern of occurrence of individual, voltage-independent, discrete release events. 相似文献