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841.
SE Patchett EM Alstead BP Saunders SV Hodgson MJ Farthing 《Canadian Metallurgical Quarterly》1997,40(2):168-171
Between 1989 and 1993, 20 intercondylar fractures of the distal humerus were treated by open reduction, internal fixation and early postoperative mobilisation. One patient died on the third postoperative day as a result of multiple injuries, leaving 19 patients for evaluation. The mean follow-up period was 4.1 years (range 2.0 to 6.7 years). According to the Muller system, there were 7 type C1 and 12 type C2 fractures. Using the Jupiter criteria, 6 elbows were rated as excellent, 9 good and 4 fair. Complications included late ulnar neuritis in one patient and wound infection in another patient. 相似文献
842.
GM Hare SE Mackinnon R Midha PY Wong B Au C Munro W Andrade DA Hunter JB Hay 《Canadian Metallurgical Quarterly》1996,17(12):697-705
Lymphocyte migration into nerve allografts was measured to estimate the cyclosporine A (CsA) dose required to suppress rejection. Twelve outbred sheep received daily subcutaneous CsA at 0, 5, 10, or 15 mg/kg/day for 2 weeks prior to implantation of multiple heterotopic subcutaneous nerve grafts. Lymphocyte migration was determined after 7 days by an intravenous pulse of autologous 111indium-labeled lymphocytes and subsequent quantitation of gamma radioactivity in nerve tissue (CPM/g, mean +/- SEM). Measurement by radioimmunoassay revealed a dose-dependent increase in blood cyclosporine levels. Lymphocyte migration into autografts (404+/-44) was significantly less than migration into allografts (16,554+/-2,049), in control animals (P < 0.01). A dose-dependent inhibition of lymphocyte migration into nerve allografts was observed with counts of 7,662+/-1,692, 4,083+/-1,112, and 1,561+/-232 in sheep receiving 5, 10, or 15 mg/kg/day of CsA, respectively. Daily CsA administration produced effective blood levels and immunosuppression sufficient to inhibit lymphocyte migration into nerve allografts. 相似文献
843.
Decompression illness in sports divers detected with technetium-99m-HMPAO SPECT and texture analysis
RT Staff HG Gemmell PM Duff PF Sharp SE Wilcock TG Shields FW Smith 《Canadian Metallurgical Quarterly》1996,37(7):1154-1158
Diving for sport and recreation has increased in recent years, resulting in more incidences of diving illness. Therefore, we studied potential use of regional cerebral blood flow SPECT imaging with 99mTc-HMPAO in the management of divers who have experienced decompression illness (DCI). METHODS: A group of ten sports divers who had no experience of DCI were compared with ten sports divers who had experienced at least one episode of DCI. Transaxial SPECT images were first compared objectively using a first-order texture measure and then subjectively using a receiver operator characteristic (ROC) experiment. Experienced observers were asked to rate images subjectively in terms of the images' textural appearance. RESULTS: Both these techniques showed that there is a statistically significant difference between the two groups and the images produced by the DCI divers were generally more coarsely patchy when compared to the non DCI divers. The quantitative texture technique proved significantly better in identifying divers with DCI than the visual analysis by observers using ROC curves. CONCLUSION: Differences between the cerebral blood flow patterns of sports divers who have experienced DCI and sports divers who have no experience of DCI can be detected using 99mTc-HMPAO SPECT and a texture analysis technique. 相似文献
844.
OBJECTIVE: To investigate the distribution patterns of primary and permanent teeth in the cleft area and the numerical variation in teeth in unilateral complete cleft lip and palate (UCLP) patients. DESIGN: A survey of the dentition in UCLP patients. SETTING: Craniofacial Center, Chang Gung Memorial Hospital, Taipei, Taiwan. PATIENTS: 137 UCLP patients who met the following criteria: (1) have had at least one panoramic film taken, (2) the first panoramic film illustrates either primary or early mixed dentition. Evaluation of both permanent and primary dentition was available in 91 cases. MAIN OUTCOME MEASURES: Two evaluators performed independent evaluations of number and distribution of teeth in UCLP patients. The hypothesis that there are two odontogenic origins for maxillary lateral incisors was proposed to explain the occurrence of distribution patterns of dentition in the cleft area and to explain differences between primary and permanent dentition in UCLP patients. RESULTS: Four distribution patterns in the cleft area were identified in both the primary and the permanent dentition. In the primary dentition, placement of the lateral incisor distal to the alveolar cleft was the predominant pattern (pattern y, 82.4%), followed by absence of the cleft side maxillary lateral incisor (pattern ab, 9.9%), presence of one tooth on each side of the alveolar cleft (pattern xy, 5.5%), and placement of the lateral incisor mesial to the alveolar cleft (pattern x, 2.2%). In the permanent dentition, the most common pattern was the absence of the maxillary lateral incisor on the cleft side (pattern AB, 51.8%), followed by lateral incisor placement distal to the alveolar cleft (pattern Y, 46%), lateral incisor placement mesial to the alveolar cleft (pattern X, 1.5%) and the presence of one tooth on each side of the alveolar cleft (pattern XY, 0.7%). The discrepancy between the distribution patterns of primary dentition and permanent dentition successors is 57.1%. Variations in tooth number in both primary and permanent dentition of UCLP patients occurred most often in the cleft area. Abnormalities in the number of teeth (hypodontia or hyperdontia) outside the cleft area were more common in the permanent dentition than in the primary dentition (24.1% versus 4.4%). CONCLUSIONS: Four distribution patterns in the cleft area were identified in both sets of dentition. Our findings of distribution patterns in UCLP patients support the hypothesis that there may be two odontogenic origins for maxillary lateral incisors. Clinicians involved in managing the dentition of UCLP patients should consider the high frequency of numerical variation both in and outside the cleft area before starting dental treatment. 相似文献
845.
SE Cwirla P Balasubramanian DJ Duffin CR Wagstrom CM Gates SC Singer AM Davis RL Tansik LC Mattheakis CM Boytos PJ Schatz DP Baccanari NC Wrighton RW Barrett WJ Dower 《Canadian Metallurgical Quarterly》1997,276(5319):1696-1699
Two families of small peptides that bind to the human thrombopoietin receptor and compete with the binding of the natural ligand thrombopoietin (TPO) were identified from recombinant peptide libraries. The sequences of these peptides were not found in the primary sequence of TPO. Screening libraries of variants of one of these families under affinity-selective conditions yielded a 14-amino acid peptide (Ile-Glu-Gly-Pro-Thr-Leu-Arg-Gln-Trp-Leu-Ala-Ala-Arg-Ala) with high affinity (dissociation constant approximately 2 nanomolar) that stimulates the proliferation of a TPO-responsive Ba/F3 cell line with a median effective concentration (EC50) of 400 nanomolar. Dimerization of this peptide by a carboxyl-terminal linkage to a lysine branch produced a compound with an EC50 of 100 picomolar, which was equipotent to the 332-amino acid natural cytokine in cell-based assays. The peptide dimer also stimulated the in vitro proliferation and maturation of megakaryocytes from human bone marrow cells and promoted an increase in platelet count when administered to normal mice. 相似文献
846.
SE Ostgaard L Gottlieb S Toksvig-Larsen A Lebech A Talbot B Lund 《Canadian Metallurgical Quarterly》1997,30(9):993-995
The two-dimensional position of markers in radiographs for Roentgen Stereophotogrammetric Analysis (RSA) is usually determined using a measuring table. The purpose of this study was to evaluate the reproducibility and the accuracy of a new RSA system using digitized radiographs and image-processing algorithms to determine the marker position in the radiographs. Four double-RSA examinations of a phantom and 18 RSA examinations from six patients included in different RSA-studies of knee prostheses were used to test the reproducibility and the accuracy of the system. The radiographs were scanned at 600 dpi resolution and 256 gray levels. The center of each of the tantalum-markers in the radiographs was calculated by the computer program from the contour of the marker with the use of an edge-detection software algorithm after the marker was identified on a PC monitor. The study showed that computer-based image analysis can be used in RSA-examinations. The advantages of using image-processing software in RSA are that the marker positions are determined in an objective manner, and that there is no need for a systematic manual identification of all the markers on the radiograph before the actual measurement. 相似文献
847.
SE Conroy GB Faulds W Williams DS Latchman DA Isenberg 《Canadian Metallurgical Quarterly》1994,33(10):923-926
Expression of the highly conserved 90 kDa heat shock protein (Hsp90) is elevated in the peripheral blood mononuclear cells of approximately 25% of patients with SLE. Conflicting data have been published about the frequency of antibodies to Hsp90 with the previous methodology using a complex Western blot system. We now describe an ELISA to measure autoantibodies to Hsp90 and Hsp70 in SLE patients, healthy controls and patients with a variety of autoimmune rheumatic diseases. IgG and IgM antibodies were elevated in 26 and 35% of SLE patients, respectively. These results show autoantibodies to Hsp90 (but not Hsp70) are elevated in a significant proportion of patients with SLE (P < 0.025) compared to healthy controls; and that those with raised antibody levels were more likely to have renal disease and a low C3 level (P < 0.02). 相似文献
848.
F DeLange CH Klaassen SE Wallace-Williams PH Bovee-Geurts XM Liu WJ DeGrip KJ Rothschild 《Canadian Metallurgical Quarterly》1998,273(37):23735-23739
We present the first Fourier transform infrared (FTIR) analysis of an isotope-labeled eukaryotic membrane protein. A combination of isotope labeling and FTIR difference spectroscopy was used to investigate the possible involvement of tyrosines in the photoactivation of rhodopsin (Rho). Rho --> MII difference spectra were obtained at 10 degrees C for unlabeled recombinant Rho and isotope-labeled L-[ring-2H4]Tyr-Rho expressed in Spodoptera frugiperda cells grown on a stringent culture medium containing enriched L-[ring-2H4]Tyr and isolated using a His6 tag. A comparison of these difference spectra revealed reproducible changes in bands that correspond to tyrosine and tyrosinate vibrational modes. A similar pattern of tyrosine/tyrosinate bands has also been observed in the bR --> M transition in bacteriorhodopsin, although the sign of the bands is reversed. In bacteriorhodopsin, these bands were assigned to Tyr-185, which along with Pro-186 in the F-helix, may form a hinge that facilitates alpha-helix movement. 相似文献
849.
850.
DR Wessner PC Shick JH Lu CB Cardellichio SE Gagneten N Beauchemin KV Holmes GS Dveksler 《Canadian Metallurgical Quarterly》1998,72(3):1941-1948
The primary cellular receptor for mouse hepatitis virus (MHV), a murine coronavirus, is MHVR (also referred to as Bgp1a or C-CAM), a transmembrane glycoprotein with four immunoglobulin-like domains in the murine biliary glycoprotein (Bgp) subfamily of the carcinoembryonic antigen (CEA) family. Other murine glycoproteins in the Bgp subfamily, including Bgp1b and Bgp2, also can serve as MHV receptors when transfected into MHV-resistant cells. Previous studies have shown that the 108-amino-acid N-terminal domain of MHVR is essential for virus receptor activity and is the binding site for monoclonal antibody (MAb) CC1, an antireceptor MAb that blocks MHV infection in vivo and in vitro. To further elucidate the regions of MHVR required for virus receptor activity and MAb CC1 binding, we constructed chimeras between MHVR and other members of the CEA family and tested them for MHV strain A59 (MHV-A59) receptor activity and MAb CC1 binding activity. In addition, we used site-directed mutagenesis to introduce selected amino acid changes into the N-terminal domains of MHVR and these chimeras and tested the abilities of these mutant glycoproteins to bind MAb CC1 and to function as MHV receptors. Several recombinant glycoproteins exhibited virus receptor activity but did not bind MAb CC1, indicating that the virus and MAb binding sites on the N-terminal domain of MHVR are not identical. Analysis of the recombinant glycoproteins showed that a short region of MHVR, between amino acids 34 and 52, is critical for MHV-A59 receptor activity. Additional regions of the N-terminal variable domain and the constant domains, however, greatly affected receptor activity. Thus, the molecular context in which the amino acids critical for MHV-A59 receptor activity are found profoundly influences the virus receptor activity of the glycoprotein. 相似文献