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The effect of a newly developed patellar realignment brace was evaluated in 21 patellofemoral joints (19 patients) with patellar subluxation (13 joints with lateral subluxation and eight with medial subluxation) by using active-movement, loaded kinematic magnetic resonance (MR) imaging. Sixteen patellofemoral joints (76%) demonstrated a qualitative correction of or improvement in patellar subluxation (ie, centralization of the patella or a decrease in the displacement of the patella) after application of the brace. Four of the five “failures” occurred in patellofemoral joints that had patella alta and/or dysplastic bone anatomy. These results indicate that the patellar realignment brace was able to counteract patellar subluxation in the majority of patellofemoral joints studied, as shown by active-movement, loaded kinematic MR imaging. This brace appears to be useful for conservative treatment of patients with patellofemoral joint pain secondary to patellar malalignment and maltracking.  相似文献   
3.
Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a recently described familial cerebrovascular disorder shown to map to chromosome 19q12. Familial hemiplegic migraine has also been shown in some families to map close to the CADASIL locus. The fully developed CADASIL phenotype consists of recurrent strokes developing in the fourth decade, progressing to a pseudobulbar palsy, spastic quadriparesis, and subcortical dementia. In an Irish family 15 members were fully investigated by magnetic resonance scanning; 10 had typical magnetic resonance features of CADASIL. Five members of this family had familial hemiplegic migraine and 4 of these had magnetic resonance evidence of CADASIL. Two other members had migraine with and without aura as a presenting clinical symptom of CADASIL. This disorder has been shown by linkage analysis to map to the CADASIL locus at chromosome 19. The phenotype at presentation of CADASIL in this family was variable and age related and included familial hemiplegic migraine, migraine with and without aura, transient ischemic attacks, strokes, and spinal cord infarction. This family study increases our understanding of the spectrum of clinical manifestations of this underrecognized familial cerebrovascular disorder.  相似文献   
4.
In order to provide a precise lymph node mapping during lung cancer surgery a sterilizable plastic tray moulded in the shape of the mediastinum and lungs is presented by the author. The device makes lymph node mapping simpler, safer, quicker and methodically more structured. A positive impact is expected as a result of usage of the device from making pathologist's work easier and facilitating the flux of information on the surgeon-pathologist-oncologist-pneumonologist chain to be more disinformation-free.  相似文献   
5.
Current surgical treatment of thoracic empyema in adults.   总被引:1,自引:0,他引:1  
A review of the recent literature on treatment modalities of adult thoracic empyema was conducted in order to expose the controversies and verify where consensus exists. Critical reading filtered through clinical experience was the method followed. The roles of surgical drainage, lavage techniques, debridement via VATS, decortication, thoracoplasty and open window thoracostomy were considered using the Oxford Center of Evidence Based Medicine criteria. The roles of the different therapeutical modalities were interpreted in the light of the triphasic nature of empyema thoracis. The randomised controlled trials came up with conflicting results. With two exceptions all of the papers reviewed provide level (2b) or below evidences. The lack of a single ideal treatment modality or policy reflects the complexity of the diagnosis and staging of this heterogeneous disease. Basic elements of intervention--drainage, different evacuation techniques, decortication, thoracoplasty and open window thoracostomy--are well-established technical modalities; however, neither a universally acceptable primary modality nor the gold standard of their sequence is available. Drainage remains to be the initial treatment modality in Phase I disease. Debridement via VATS is a safe, reliable and efficient method in the fibrinopurulent phase. Organised pleural callus requires formal decortication. Open window thoracostomy is a simple and safe procedure for high-risk patients and results in quick detoxication. Thoracoplasty kept its final role in pleural space management. Acute postoperative bronchial stump insufficiency requires immediate surgery. Evacuation of toxic material is mandatory. No single-stage procedure offers a solution. An optimised agressivity treatment modality should be tailored to the condition of the patient and to the potential of the persisting cavity. Decision-making involves a triad consisting of the aetiology of empyema (i.e. primary vs secondary), general condition of the patient and stage of disease, while considering the triphasic nature of development of thoracic empyema. The current attitudes show that the present concepts are based mainly on expert opinion. Flexibility and patience on behalf of the surgeon and nursing staff, the patient and the hospital management, as well as a good understanding of the complexity of this condition are the cornerstones of the treatment. No exclusive sequence of procedures leading to a uniformly predictable successful outcome is available. Individualised approaches can be recommended based on institutional practice and local protocols. Thoracic empyema in general seems to remain resilient to fit completely into the categories of evidence-based medical approach.  相似文献   
6.
Cerebrospinal fluid 5-hydroxyindoleacetic acid (CSF 5HIAA), homovanillic acid, and tryptophan were measured in 33 depressed, 36 alcoholic, and 32 neurological control female patients selected by strict operational criteria and investigated under controlled circumstances. Plasma total tryptophan was also measured in blood samples taken simultaneously with lumbar punctures. A multivariate regression analysis was done to discover the effect of age, height, and body weight on these four biochemical measures. Only CSF 5HIAA was significantly dependent on the nonspecific patient variables: height, but neither age nor weight, accounted for more than 10% of the variance of 5HIAA. The same analysis was carried out in all three separate patient groups: the relationship between height and CSF 5HIAA was present throughout, and only 2 of 12 correlations proved to be non-homogeneous. To demonstrate the significantly of these clinical parameters a multivariate analysis of covariance was done to eliminate their effect on the four biochemical variables. As a result significant differences emerged in CSF 5HIAA and total plasma tryptophan for some of the patient groups which were not demonstrable without this correction.  相似文献   
7.
Psychological distress was observer-rated with the Brief Psychiatric Rating Scale (BPRS) and self-rated with the Symptom Questionnaire (SQ) every other week for a 6-month period in 9 apparently remitted bipolar patients attending a lithium clinic. Substantial clinical fluctuations in psychopathology were observed with both rating methods. Compared to normal control subjects, patients suffering from bipolar disorder displayed significantly higher BPRS and SQ anxiety, somatization and total distress scores.  相似文献   
8.
Role of endogenous cannabinoids in synaptic signaling   总被引:32,自引:0,他引:32  
Research of cannabinoid actions was boosted in the 1990s by remarkable discoveries including identification of endogenous compounds with cannabimimetic activity (endocannabinoids) and the cloning of their molecular targets, the CB1 and CB2 receptors. Although the existence of an endogenous cannabinoid signaling system has been established for a decade, its physiological roles have just begun to unfold. In addition, the behavioral effects of exogenous cannabinoids such as delta-9-tetrahydrocannabinol, the major active compound of hashish and marijuana, await explanation at the cellular and network levels. Recent physiological, pharmacological, and high-resolution anatomical studies provided evidence that the major physiological effect of cannabinoids is the regulation of neurotransmitter release via activation of presynaptic CB1 receptors located on distinct types of axon terminals throughout the brain. Subsequent discoveries shed light on the functional consequences of this localization by demonstrating the involvement of endocannabinoids in retrograde signaling at GABAergic and glutamatergic synapses. In this review, we aim to synthesize recent progress in our understanding of the physiological roles of endocannabinoids in the brain. First, the synthetic pathways of endocannabinoids are discussed, along with the putative mechanisms of their release, uptake, and degradation. The fine-grain anatomical distribution of the neuronal cannabinoid receptor CB1 is described in most brain areas, emphasizing its general presynaptic localization and role in controlling neurotransmitter release. Finally, the possible functions of endocannabinoids as retrograde synaptic signal molecules are discussed in relation to synaptic plasticity and network activity patterns.  相似文献   
9.
Multiple hormones controlling energy homeostasis regulate the expression of neuropeptide Y (NPY) and agouti-related peptide (AgRP) in the arcuate nucleus of the hypothalamus. Nevertheless, inactivation of the genes encoding NPY and/or AgRP has no impact on food intake in mice. Here we demonstrate that induced selective ablation of AgRP-expressing neurons in adult mice results in acute reduction of feeding, demonstrating direct evidence for a critical role of these neurons in the regulation of energy homeostasis.  相似文献   
10.
GABAergic interneurones are essential in cortical processing, yet the functional properties of their dendrites are still poorly understood. In this first study, we combined two-photon calcium imaging with whole-cell recording and anatomical reconstructions to examine the calcium dynamics during action potential (AP) backpropagation in three types of V1 supragranular interneurones: parvalbumin-positive fast spikers (FS), calretinin-positive irregular spikers (IS), and adapting cells (AD). Somatically generated APs actively backpropagated into the dendritic tree and evoked instantaneous calcium accumulations. Although voltage-gated calcium channels were expressed throughout the dendritic arbor, calcium signals during backpropagation of both single APs and AP trains were restricted to proximal dendrites. This spatial control of AP backpropagation was mediated by Ia-type potassium currents and could be mitigated by by previous synaptic activity. Further, we observed supralinear summation of calcium signals in synaptically activated dendritic compartments. Together, these findings indicate that in interneurons, dendritic AP propagation is synaptically regulated. We propose that interneurones have a perisomatic and a distal dendritic functional compartment, with different integrative functions.  相似文献   
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