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Halliday SE Zavatsky AB Hase K 《Archives of physical medicine and rehabilitation》2004,85(8):1265-1272
OBJECTIVE: To compare the ergometer rowing technique of a person with spinal cord injury (SCI), using functional electric stimulation (FES) of his leg muscles, with that of a well-defined group of able-bodied rowers. DESIGN: Whole-body kinematics and kinetics and electric activity of selected muscles were measured during ergometer rowing. SETTING: A hospital-based motion analysis laboratory. PARTICIPANTS: Five male university varsity-level rowers and 1 male rower with SCI. INTERVENTIONS: Eight rowing trials were collected on the university-level rowers, 2 trials each at 20, 24, 28, and 32 strokes/min. The rower with SCI had surface electrodes applied to his medial hamstrings and medial quadriceps muscle bellies. The electrodes were attached to a stimulator that was activated using a button in the ergometer handle. The subject with SCI rowed at a self-selected stroke rate. MAIN OUTCOME MEASURES: Forces at the ergometer handle and foot cradle, 3-dimensional whole-body kinematics, net joint moments, and phasic activity of muscles. RESULTS: Motion of the arms, ankles, and knees of the rower with SCI was similar to those of the university-level rowers; other joint motions and forces applied to the ergometer differed. CONCLUSIONS: FES-assisted rowing in its current implementation cannot reproduce a race-winning rowing stroke. Further development work is required. 相似文献
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产后出血的预防和处理指南 总被引:3,自引:0,他引:3
目的:为产后出血(PPH)的预防和临床处理作一综述,为临床医师提供预防和处理产后出血的指南。涉及方面:预防、适当干预、使其影响最小化的方法。结果:建立常规,便于临床医师鉴别可能的高危人群,一旦发生产后过多出血,可指导临床如何迅速处理。证据:遵循加拿大定期健康检查办公室制定的证据等级。评估:由产科专家完善。利弊和成本:评估子宫收缩药和其他积极处理措施的方便性、正确性、有效性和安全性。建议:根据证据的等级,本指南分等级列出了12条建议。确认:按照MeSH词表推荐的postpartum haemorrhage在medline上查询相关文献,在Cochrane图书馆查找相关研究文献,并参考the ALARMcourse Manual。发起人:由产科临床实践委员会制定和综述,并由SOGC(加拿大妇产科协会)委员会批准。 相似文献
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AB Kimball U Gieler D Linder F Sampogna RB Warren M Augustin 《Journal of the European Academy of Dermatology and Venereology》2010,24(9):989-1004
Psoriasis is associated with significant physical and psychological burden affecting all facets of a patient’s life – relationships, social activities, work and emotional wellbeing. The cumulative effect of this disability may be self‐perpetuating social disconnection and failure to achieve a ‘full life potential’ in some patients. Health‐related quality of life studies have quantified the burden of psoriasis providing predominantly cross‐sectional data and point‐in‐time images of patients’ lives rather than assessing the possible cumulative disability over a patient’s lifetime. However, social and economic outcomes indicate there are likely negative impacts that accumulate over time. To capture the cumulative effect of psoriasis and its associated co‐morbidities and stigma over a patient’s life course, we propose the concept of ‘Cumulative Life Course Impairment’ (CLCI). CLCI results from an interaction between (A) the burden of stigmatization, and physical and psychological co‐morbidities and (B) coping strategies and external factors. Several key aspects of the CLCI concept are supported by data similar to that used in health‐related quality of life assessments. Future research should focus on (i) establishing key components of CLCI and determining the mechanisms of impairment through longitudinal or retrospective case–control studies, and (ii) assessing factors that put patients at increased risk of developing CLCI. In the future, this concept may lead to a better understanding of the overall impact of psoriasis, help identify more vulnerable patients, and facilitate more appropriate treatment decisions or earlier referrals. To our knowledge, this is a first attempt to apply and develop concepts from ‘Life Course Epidemiology’ to psoriasis research. 相似文献
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Creutzfeldt--Jakob Disease in Recipients of Human Growth Hormone in the United Kingdom: A Clinical and Radiographic Study 总被引:1,自引:0,他引:1
MARKUS HS; DUCHEN LW; PARKIN EM; KURTZ AB; JACOBS HS; COSTA DC; HARRISON MJ 《QJM : monthly journal of the Association of Physicians》1992,82(1):43-51
In the past 3 years there have been five further cases, in additionto one case reported in 1985, of Creutzfeldt-Jakob disease inrecipients of human growth hormone in the United Kingdom. Theclinical findings of two of these cases are described, demonstratinga typical presentation with a predominantly cerebellar syndromeat onset which is not commonly a presenting feature of sporadicCreutzfeldt-Jakob disease. In one case a 99mTc hexamethylpropylenaminesingle photon emission tomographic scan showed marked impairmentof tracer uptake in the basal ganglia and cerebral cortex ata time when the clinical picture was predominantly cerebellar.This technique may be useful in early diagnosis. In the othercase post mortem examination of the brain showed prominent amyloiddeposition in the cerebellum, which has not been described previouslyin pituitary-hormone related Creutzfeldt-Jakob disease. Thepreviously published cases of growth hormone-related Creutzfeldt-Jakobdisease are reviewed and reasons for the particular clinicalpattern seen are discussed. 相似文献
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Down-regulation of mannosyl receptor-mediated endocytosis and antigen F4/80 in bacillus calmette-guerin-activated mouse macrophages. Role of T lymphocytes and lymphokines 总被引:2,自引:1,他引:2 下载免费PDF全文
Bacillus Calmette-Guerin (BCG) infection alters the surface and endocytic properties of mouse peritoneal macrophages (PM) compared with thioglycollate- elicited (TPM) or resident PM (RPM). Expression of Ia antigen (Ag) is enhanced up to fourfold, but plasma membrane receptors that mediate binding and uptake of mannosyl/fucosyl-terminated glycoconjugates (MFR), Fc receptors, and the macrophage (m)-specific Ag F4/80 are reduced by 50-80 percent. Levels of Mac-1 remain relatively stable. These changes are accompanied by enhanced secretion of O(2)(-), after further stimulation with phorbyl myristate acetate, and of plasminogen activator. Both these products are released by TPM, but not RPM. The characteristic surface phenotype of BCG-PM can also be induced by injection of C. parvum, another m- activating agent, but not by thioglycollate broth, lipopolysaccharide, or proteose peptone. Purified protein derivative (PPD) and N-acetylmuramyl-L- alanyl-D-isoglutamine. 2H(2)0 are soluble agents with partial activity. Alteration of m markers by BCG infection depends on T lymphocyte function, although studies with nude mice indicate that other pathways may also serve to modify the surface of the m. M from uninfected animals displayed all markers of activation after adoptive transfer of specifically-sensitised lymphocytes with PPD, intraperitoneally, or after co- cultivation. Treatment of primed lymphocytes with anti-Thy-1 antibody and complement ablated this effect. Lymphokines obtaned by Ag or mitogen stimulation induced similar changes in TPM and RPM. Mannose-specific endocytosis decayed rapidly, time 1/2 approximately equal to 16 h and stabilized at approximately 25 percent of control values. Single-cell analysis showed that residual MFR activity was uniform in the target population. Loss of Ag F4/80 after activation by lymphocyte and PPD was less marked than after infection (35 percent vs 80 percent), unlike MFR activity, which declined to a similar extent. Induction of m Ia by lymphokine reached a peak after 2-3 d and was lost within 2 d of its removal. Recovery of MFR and F4/80 was incomplete under these conditions. These studies establish that activated m known to display enhanced antimicrobial/anticellular activity express markedly different surface properties distinct from elicited or resident cells. The role of antigen- stimulated T cell products in regulating m function is confirmed, and down-regulation of mannosyl-receptor-mediated endocytosis provides a sensitive, quantitative, and cell-specific new marker to study their properties and mechanism of action. Extensive, but selective remodeling of m plasma membrane structure could play an important role in controlling recognition and effector mechanisms of the activated m. 相似文献
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