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21.
PA DeLuca 《Canadian Metallurgical Quarterly》1996,43(5):1135-1150
Orthopedic management of children with cerebral palsy is best accomplished with a team approach, which generally is effective in the other neuromotor disabilities of childhood, such as myelomeningocele and muscle disease. Because contracture development is inevitable in growing children with spastic musculature or muscle imbalance and is a prime cause of musculoskeletal dysfunction, its control over time using therapy, bracing, and medication is essential. Problems such as severe contracture, joint deformity, and scoliosis interfere with the basic requirement of comfortable seating in children with quadriplegic involvement and frequently require surgery. In ambulatory children, the use of three-dimensional gait analysis has allowed multilevel surgery to be appropriately planned, minimizing exposure to surgery and therapy. 相似文献
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BACKGROUND: Hydrogen exchange labelling has been a key method in characterizing the structure of transient folding intermediates. In studies of several proteins, however, there has been clear spectroscopic evidence for partial folding of some kind at very early times, before any protection from exchange was measurable. These results, presumably a consequence of limited stability of specific backbone interactions, have made it difficult to assess the extent of native-like folding in the very early intermediates. We have used a variant of the labelling method to investigate marginally stable structures formed within the first few milliseconds of refolding of two such proteins, hen lysozyme and ubiquitin. RESULTS: In lysozyme, population of a subset of native-like secondary structures on this timescale is revealed, thus reconciling the exchange behaviour with circular dichroism measurements and confirming the significance of the rapidly formed embryonic structure as a foundation for the subsequent folding pathway. In the case of ubiquitin, by contrast, no significantly protective structure was detectable, suggesting that here secondary structural elements can be populated only marginally ahead of the major cooperative folding event; this was also supported by stopped-flow circular dichroism measurements. CONCLUSIONS: The hydrogen exchange approach can be extended to probe the formation of native-like structure formed in very early folding intermediates, even when the stability of specific interactions is marginal. In the case of lysozyme, this has provided a new window on an early stage of organization of the alpha-helical domain. 相似文献
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PA Galindo E Gómez J Borja F Feo R García M Lombardero D Barber 《Canadian Metallurgical Quarterly》1998,26(5):251-254
Incidence of gastrointestinal tuberculosis increases in the western world. Exact epidemiological data about this rare extrapulmonological disease are not available in Hungary. Three advanced cases with intestinal tuberculosis have been reported, all of them recognised during surgery due to complications. The clinicopathological correlations are briefly reviewed, and the importance of early diagnosis is emphasized. 相似文献
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PA Granato 《Canadian Metallurgical Quarterly》1993,16(3):237-243
Within the last decade, major technologic advances have been made in clinical microbiology that have resulted in the availability of a wide variety of different methods for the rapid reporting of test results. Included among these technologies are rapid methods for producing antimicrobial susceptibility reports that many regard as the most important information generated by the microbiology laboratory. Ideally, the early availability of this important information should favorably affect patient care by enabling the more judicious use of alternative drug therapies that are equally efficacious yet less toxic and less costly to the patient. Clinicians appear to have been reluctant to modify initial empiric therapies, however, despite the availability of the rapid antimicrobial susceptibility report. This article addresses some of the issues responsible for this long-standing problem and discusses and explores various strategies that can be implemented for improving the use and for controlling the cost of antimicrobial agents within the hospital. 相似文献
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PA Bond 《Canadian Metallurgical Quarterly》1993,40(5):301-308
To evaluate the difference in left ventricular function during exercise after successful aortic valve replacement, left ventricular function was investigated using radionuclide angiography in 12 patients with normal resting left ventricular systolic function. Patients were divided into two groups: Group 1 was comprised of 5 patients after aortic valve replacement for aortic stenosis and group 2 was comprised of 7 patients for aortic insufficiency. Left ventricular ejection fraction increased significantly during exercise in both groups. The increase in systolic arterial pressure to left ventricular end-systolic volume was significantly larger in group 1 than group 2, whereas the increase in left ventricular end-diastolic volume was significantly larger in group 2 than group 1. Thus, increase in left ventricular contractility played an important role in regulating increased left ventricular ejection fraction during exercise in patients with aortic prostheses for aortic stenosis, whereas increase in left ventricular end-diastolic volume played an important role in patients with aortic prostheses for aortic insufficiency. 相似文献
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PA Bullock 《Canadian Metallurgical Quarterly》1997,32(6):503-568
DNA replication is a complicated process that is largely regulated during stages of initiation. The Siman Virus 40 in vitro replication system has served as an excellent model for studies of the initiation of DNA replication, and its regulation, in eukaryotes. Initiation of SV40 replication requires a single viral protein termed T-antigen, all other proteins are supplied by the host. The recent determination of the solution structure of the T-antigen domain that recognizes the SV40 origin has provided significant insights into the initiation process. For example, it has afforded a clearer understanding of origin recognition, T-antigen oligomerization, and DNA unwinding. Furthermore, the Simian virus 40 in vitro replication system has been used to study nascent DNA formation in the vicinity of the viral origin of replication. Among the conclusions drawn from these experiments is that nascent DNA synthesis does not initiate in the core origin in vitro and that Okazaki fragment formation is complex. These and related studies demonstrate that significant progress has been made in understanding the initiation of DNA synthesis at the molecular level. 相似文献
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