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41.
42.
ID Young 《Canadian Metallurgical Quarterly》1998,352(9145):1950-1951
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Measurement of synovial lining volume by magnetic resonance imaging of the knee in chronic synovitis
G Clunie MA Hall-Craggs MN Paley A King ID Wilkinson PJ Ell JC Edwards 《Canadian Metallurgical Quarterly》1997,56(9):526-534
OBJECTIVES: Current methods of monitoring chronic synovitis in a single joint rely on clinical examination derived indices, such as the detection of synovial thickening. This study aimed to develop a reproducible method for quantifying the volume of synovial lining in chronic synovitis using contrast enhanced magnetic resonance (MR) imaging. METHODS: The knees of 18 patients with chronic synovitis were examined (34 studies). A 2D T1 weighted FLASH sequence was used to evaluate the temporal enhancement of synovial structures after intravenous contrast. Synovial lining volume was calculated from subtraction of pre and post-enhancement 3D T1 weighted MP RAGE images with thresholding and pixel counting. Eleven patients were examined before and after intra-articular glucocorticoid (mean interval 14 weeks) and MR data compared with changes in clinical examination derived indices of disease activity. RESULTS: Synovial lining volume varied from 52-267 ml. The coefficient of variation in volume calculation was 3.5% for a single observer and was 3.8% for two observers. Synovial lining volume was quantified in all patients where synovial lining thickening could not be detected clinically. A decrease in synovial lining volume of > 40% was associated with an improvement in synovial lining thickening, detected clinically. Decreases in synovial lining volume were quantified by MR in two of three patients where changes in clinical examination derived indices were inconsistent. CONCLUSIONS: A reproducible method of estimating the volume of synovial lining in patients with chronic synovitis has been developed. MR measurement of synovial lining volume may quantify changes in chronic synovitis that remain unidentified by clinical measures. 相似文献
45.
Although there is a large body of site-directed mutagenesis data that identify the pore-lining sequence of the voltage-gated potassium channel, the structure of this region remains unknown. We have interpreted the available biochemical data as a set of topological and orientational restraints and employed these restraints to produce molecular models of the potassium channel pore region, H5. The H5 sequence has been modeled either as a tetramer of membrane-spanning beta-hairpins, thus producing an eight-stranded beta-barrel, or as a tetramer of incompletely membrane-spanning alpha-helical hairpins, thus producing an eight-staved alpha-helix bundle. In total, restraints-directed modeling has produced 40 different configurations of the beta-barrel model, each configuration comprising an ensemble of 20 structures, and 24 different configurations of the alpha-helix bundle model, each comprising an ensemble of 24 structures. Thus, over 1300 model structures for H5 have been generated. Configurations have been ranked on the basis of their predicted pore properties and on the extent of their agreement with the biochemical data. This ranking is employed to identify particular configurations of H5 that may be explored further as models of the pore-lining region of the voltage-gated potassium channel pore. 相似文献
46.
DM Keeling R Luddington JP Allain AS Lawrie LM Williamson 《Canadian Metallurgical Quarterly》1997,96(1):194-197
The newly discovered peptide nociceptin/orphanin FQ has been found to increase reactivity to pain and to influence locomotor activity after intracerebroventricular administration. This study investigated the possible role of hippocampal nociceptin/orphanin FQ in spatial learning and in spontaneous locomotion. Male rats were trained in the Morris water task after microinjection of 10 nmol nociceptin/orphanin FQ or artificial cerebrospinal fluid (as control) into the CA3 region of the dorsal hippocampus. Nociceptin/orphanin FQ was found to severely impair spatial learning without interfering with swimming performance. Intrahippocampal injection of nociceptin/ orphanin FQ markedly decreased exploratory locomotor activity including vertical movements (rearing). The data suggest that nociceptin/orphanin FQ is a potent modulator of synaptic plasticity within the hippocampus. 相似文献
47.
BACKGROUND AND OBJECTIVE: The long-term success of trabeculectomy depends primarily on the degree of scarring that occurs to the artificial filtration route that is created by the procedure. The most serious postoperative complication of trabeculectomy is a persistent shallow anterior chamber or a flat chamber. The objective of this study was to evaluate the effect of a suturing technique on the long-term success of trabeculectomy. PATIENTS AND METHODS: In this study, the authors analyzed a trabeculectomy technique that is based on the application of a suture of variable tightness on the scleral flap. The technique was performed on 11 patients subjected to trabeculectomy. RESULTS: The postoperative complication of shallow anterior chamber was successfully treated with further tightening of the suture for one patient. For each patient, the authors loosened the suture on the fourth postoperative day and removed it completely on the seventh or eighth postoperative day. The patients were observed postoperatively for a minimum of 1 year. During this period the intraocular pressure for each patient was within the normal limits. CONCLUSION: The authors contend that this trabeculectomy technique, in which a suture on the scleral flap can be adjusted for tightness and is later removed, contributes significantly to the treatment of a postoperative shallow anterior chamber or a flat chamber and to the long-term function of an effective filtration fistula. 相似文献
48.
'English' type fresh skinless sausages were prepared in which some of the meat (mutton, pork or beef) was replaced on a protein to protein basis by chickpea flour. The acceptability of mutton sausages containing chickpea flour was not affected at levels of substitution up to 40%, whereas pork and beef sausages were significantly less acceptable at substitution levels above 30%. In all the sausages incorporation of chickpea flour led to increased cooking losses and softer textures. Incorporation of chickpea flour caused discoloration of the raw sausages which became more prominent during storage at 0°C. 相似文献
49.
G Savini JD Dunsmore ID Robertson P Seneviratna 《Canadian Metallurgical Quarterly》1993,70(4):152-154
The Jamaican Perinatal Morbidity and Mortality Survey (1986-1987) revealed nine cases of a previously unreported form of birth-related injury in the English-speaking Caribbean--occipital osteodiastasis. Aspects of the clinical and pathological features of this form of occipital bone injury are presented and discussed. Our findings suggest that this lesion might occur more often than is currently accepted. 相似文献
50.
DG Doak D Mulvey K Kawaguchi J Villalain ID Campbell 《Canadian Metallurgical Quarterly》1996,258(4):672-687
Peptides representing transmembrane regions of the alpha-subunit of the voltage-gated sodium channel were synthesised and their structures analysed, using 1H NMR and CD, in trifluoroethanol and in dodecylphosphocholine micelles. Sequence analysis suggests that the channel has six regions, S1 to S6, predicted to span the membrane in four homologous domains, designated, I, II, III and IV. Presented here are studies of representatives examples of possible single spanning segments (IS2, IS4, IVS4) and a double spanning segment, IS34, composed of segments IS3 and IS4. In addition, we investigated ISlink56, the putative linker region between segments IS5 and IS6. All of the peptides were found to have predominantly alpha-helical structures in both solvent systems. There was some evidence for bending of the longer helices but there was no discernible evidence for well-defined tertiary structure. 相似文献