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61.
This contribution aims to review the major findings of pre- and postsurgical functional magnetic resonance imaging (fMRI) in patients with refractory epilepsy from a neuropsychological perspective. We compared the contribution of fMRI with the intracarotid amytal procedure (IAP) with respect to functional mapping of language and memory in patients with therapy-resistant epilepsy. We conclude that using comprehensive language paradigms, fMRI has been able (1) to provide estimates of the degree of language lateralization including the degree of involvement of the nondominant hemisphere, (2) to provide information on the location of its activated network during expressive and receptive language, and (3) to help delineate eloquent language regions in the vicinity of the surgical target, thus preventing postoperative complications. The contribution of the frequently observed nondominant hemisphere activation to language should be explored and its clinical relevance determined. Evidence from fMRI studies is accumulating that reorganization of cognitive and motor function favors the activation of contralateral homotopic areas, although this process is far from understood. The exact functional contribution of atypical areas of activation should be investigated critically. In the presurgical evaluation process, detailed and reliable localization of language and memory functions of the individual patient is mandatory and should be the ultimate goal in the development of comprehensive clinical fMRI protocols.  相似文献   
62.
Neural signals from proprioceptors in muscles provide length and force-related linkages among muscles of the limbs. The functions of this network of heterogenic reflexes remain unclear. New data are reported here on the distribution and magnitudes of neural feedback among quadriceps and triceps surae muscles in the decerebrate cat. The purpose of this paper was to distinguish whether inhibitory-force feedback is directed against muscles by virtue of the motor-unit composition or articulation of the muscle. These studies were carried out using controlled stretches and measurements of the resulting force responses of individual quadriceps and triceps surae muscles. Responses were evoked over a wide range of background force levels. In agreement with earlier electrophysiological studies, excitatory length feedback strongly linked the vastus muscles, but excitatory reflexes between each vastus and rectus femoris muscles were weak. We also observed a substantial excitatory linkage from the vastus muscles to the soleus muscle. In contrast, force-related inhibition was absent in the heterogenic reflexes among the vastus muscles but strong and bidirectional between each vastus muscle and the rectus femoris muscle and between triceps surae and quadriceps muscles. We conclude that short-latency feedback in the hindlimb is organized according to muscle articulation. Length feedback within muscle groups regulates joint stiffness while interjoint length feedback may compensate for the effects of nonuniform inertial properties of the limb. Force feedback is organized to regulate coupling between joints and, along with length feedback, determine the mechanical properties of the endpoint.  相似文献   
63.
A recent publication by the Canadian Early and Mid-Trimester Amniocentesis Trial Group reported an increase in orthopaedic foot deformities in infants whose mothers underwent an amniocentesis from 11 to 12 + 6 gestational weeks versus a group sampled between 15 to 16 + 6 gestational weeks. Because the sampling of the former group was at the time of maximum foot growth and maximum acquisition of amniotic fluid, the authors hypothesize that the foot deformities are secondary to decreased fetal movement during a key phase in foot and ankle development.  相似文献   
64.
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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66.
A 35-year-old man with ulcerative colitis who was receiving parenteral feeding with large amounts of glucose, suddenly developed severe optic neuropathy and oculomotor palsy. The visual acuity fell bilaterally to 0. Although it was stated that thiamine has been regularly suppleted in the preceding period, high doses of vitamin B1 were given. Visual acuity promptly returned to 1.0 but large visual field defects persisted. Later on it appeared that erroneously no vitamin B1 has been given before.  相似文献   
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68.
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   
69.
70.
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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