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21.
T. M. Skerry M.D. M.R.C.V.S. R. Suswillo A. J. El Haj N. N. Ali R. A. Dodds L. E. Lanyon 《Calcified tissue international》1990,46(5):318-326
Summary Previous studies of Alcian blue-induced birefringence in adult avian cortical bone showed that a short period of intermittent
loading rapidly produces an increased level of orientation of proteoglycans within the bone tissue. In the absence of further
loading, this persists for over 24 hours. We have proposed that this phenomenon could provide a means for “capturing” the
effects of transient strains, and so provide a persistent, constantly updated strain-related influence on osteocyte populations
related to the bones' averaged recent strain history, in effect, a “strain memory” in bone tissue. In our present study, we
use the Alcian blue-induced birefringence technique to demonstrate that proteoglycan orientation also occurs after intermittent
loading of both cortical and cancellous mammalian bonein vivo andin vitro. We also show that the change in birefringence is proportional to the magnitude of the applied strain, and that the reorientation
occurs rapidly, reaching a maximal value after only 50 loading cycles. Examination of electron micrographs of bone tissue
after staining with cupromeronic blue allows direct visualization and quantification of the change in proteoglycan orientation
produced by loading. This shows that intermittent loading is associated with a realignment of the proteoglycan protein cores,
bringing them some 5 degrees closer to the direction of collagen fibrils in the bone matrix. 相似文献
22.
23.
This report describes a model for identifying sets of teaching abilities considered to be effective for medical school teaching staff, based on roles teachers assume and functions they are expected to perform as instructors. The specification of these teaching abilities was the first step in the development of a comprehensive course on Medical Instruction at the Basic Institute of Medical and Agricultural Biology of the State University of Sao Paulo, Botucatu, Brazil, where the senior author is employed. The work was based on the assumption that medical school teachers are expected to assume a variety of teaching roles and that identification and specification of the abilities that define their roles can result in more effective and efficient teaching. 相似文献
24.
The role of infection and vaccination in the genesis of optic neuritis and multiple sclerosis in children 总被引:2,自引:0,他引:2
R. Riikonen 《Acta neurologica Scandinavica》1989,80(5):425-431
This article describes the association between previous infection and/or vaccination and the development of optic neuritis (ON) in 18 children. Ten of these children subsequently developed clinically definite multiple sclerosis (MS), while in 8 patients a clinically definite etiology could not be confirmed. Vaccination preceded the first ON attack in 6 patients, all but one of whom subsequently developed MS. It also preceded subsequent demyelinating events in 6 patients. Ten of the patients had a bacterial or viral infection within the 2 weeks prior to the first symptoms of ON. Intrathecal antibody synthesis against 2 or more viruses could be shown in 5 out of 8 patients studied; 5 out of 6 patients had oligoclonal antibodies in CSF and 12 out of 16 patients a high IgG index. Neither intrathecal antibody synthesis against 2 or more viruses nor elevated IgG indexes could be found in the control patients. Measles and mumps occurred at a significantly later age in the children who subsequently developed MS than in the control children, and these patients had significantly more events that might have impaired the blood-brain barrier than the controls. These results indicate that immunological events leading to MS may be triggered during childhood. Vaccination and infection often precede ON in childhood. Intrathecal viral antibody production can occur already in childhood at the time of the first symptoms of MS. 相似文献
25.
目的观察中西医结合治疗慢性鼻窦炎的疗效.方法:对76例慢性鼻窦炎病人采用阿奇霉素,每次1粒(0.25g),替硝唑片每次1g口服,二者均一日1次,首剂量加倍,中成药藿胆丸每次服6克,一日两次,7天为一疗程,服药最长者2周。结果:显效56例(占73.7%),有效18例(占23.7%),无效2例(占2.6%),总有效率97.4%。结论:中西医结合治疗慢性鼻窦炎具有良好疗效。 相似文献
26.
Background contextLarge, prominent osteophytes along the anterior aspect of the cervical spine have been reported as a cause of dysphagia. Improvement of swallowing after surgical resection has been reported in a few case reports with short-term follow-up. The current report describes outcomes of a series of five patients with surgical treatment for this rare disorder, with a long-term follow-up.PurposeTo study the clinical and radiographic outcomes of a case series of patients surgically treated for dysphagia secondary to cervical diffuse idiopathic skeletal hyperostosis (DISH).Study designRetrospective review of a case series.Patient sampleFive cases from a University Hospital.Outcome measuresClinical and imagenological follow-up.MethodsThe records of five patients with dysphagia who had undergone anterior surgical resection of prominent osteophytes secondary to DISH were reviewed. Extrinsic esophageal compression secondary to anterior cervical osteophytes was radiographically confirmed via preoperative barium esophagogram swallowing study. All patients underwent anterior cervical osteophytes resection without fusion. Postoperatively, patients were followed-up clinically and radiographically with routine lateral cervical radiographs.ResultsPreoperative esophagogram showed that the esophageal obstruction was present at one level in three cases and two levels in two cases. The C3–C4 level was involved in three cases, C4–C5 in three cases, and C5–C6 in one case. There were no postoperative complications, including recurrent laryngeal nerve palsy, wound infection, or hematomas. All patients had resolution of dyphagia soon after surgery (within 2 weeks). Postoperative radiographs demonstrated complete removal of osteophytes. At final follow-up, ranging from 1 to 9 years (average 59.8 months, median 53 months), no patients reported recurrence of dysphagia. Final radiographic examination demonstrated minimal regrowth of the osteophytes.ConclusionsAlthough rarely indicated, surgical resection of anterior cervical osteophytes from DISH causing dyphagia produces good clinical and radiographical outcomes. After thorough evaluation to rule out other intrinsic or extrinsic causes of swallowing difficulty, surgical treatment of this uncommon condition might be considered. 相似文献
28.
In 2002/2005, separate energy requirement equations were generated by the Institute of Medicine's (IOM) Dietary Reference Intake process for normal weight and overweight/obese children and adolescents. The current paper questions the theoretical rationale of having two sets of equations (based solely on body-weight classification): when body weight is considered, overweight and obese children and adolescents do not seem to differ from their normal weight counterparts in energy expended for basal metabolism or physical activity tasks. However, energy needs for weight maintenance among overweight/obese girls were consistently higher when predicted using the equations for overweight/obese individuals compared with those developed for normal weight individuals. In contrast, among overweight/obese boys, they were consistently lower . Although the differences are within the variability of the estimates, even theoretical support for a higher energy intake (as occurs in girls) seems unwise because of the potential contribution to a higher body mass in children who are already at risk. It is the opinion of the authors that the IOM revisit the use of two separate equations and generate one set that is appropriate for all children and adolescents. 相似文献
29.
With the advent of computerized databases, medical data has become easy to accumulate; however, effective use of this data continues to pose significant problems. In other circumstances, smoothing algorithms have been used to uncover non-obvious correlations, trends and relationships in noisy data. We have applied four such algorithms to a large dataset of postoperative blood replacement in cardiopulmonary bypass patients. When applied to this dataset, one of the algorithms proved surprisingly effective. It confirmed several previously observed correlations, and also provided an additional series of counterintuitive and apparently unrelated associations. These associations have been explored in an accompanying paper. 相似文献
30.
目的:探讨使用便携式微量输液泵在肿瘤化疗中持续输注氟尿嘧啶的应用效果。方法:选取我科2006年3月-2008年7月96例癌症化疗病人按入院先后顺序分为对照组和实验组,每组48例。对照组采用传统的化疗方式,采用浅静脉留置针直接从外周静脉输注氟尿嘧啶(5-Fu)连续5天,每天维持6-8小时。实验组采用浅静脉留置针连接便携式微量输液泵持续泵入氟尿嘧啶(5-Fu)120h~135h,两组均以21天为1个周期,观察两组病人化疗毒副反应发生情况。结果:实验组化疗毒副反应发生率明显低于对照组,平均住院时间明显缩短,两组比较差异有统计学意义(P〈0.01)。结论:使用便携式微量输液泵持续泵入氟尿嘧啶能减轻病人的毒副反应,缩短住院时间,提高肿瘤病人生活质量,有效减轻护士的工作负担。 相似文献