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151.
We report on a woman with a an 8-year history of multiple system atrophy with predominance of parkinsonism who developed jaw-locking oromandibular dystonia within hours after insertion of ill-fitting dentures. Dystonia spread rapidly to involve other facial muscles and the larynx causing stridor with respiratory failure necessitating crush intubation.  相似文献   
152.
The opioid transmitters enkephalin and dynorphin are known to regulate pallidal output and consequently cortical excitability. Indeed, abnormal basal ganglia opioid transmission has been reported in several involuntary movement disorders, including levodopa-induced dyskinesias in Parkinson's disease (PD), tardive dyskinesias/dystonia, Huntington's disease, and Tourette's syndrome. Moreover, a previous 11C-diprenorphine PET study investigating levodopa-induced dyskinesias found reduced opioid receptor availability in PD with but not without dyskinesias. We wished to investigate if a similar alteration in basal ganglia opioid binding was present in DYT1 primary torsion dystonia (PTD). Regional cerebral 11C-diprenorphine binding was investigated in 7 manifesting carriers of the DYT1 gene and 15 age-matched normal controls using a region-of-interest (ROI) approach and statistical parametric mapping (SPM). No difference in regional mean 11C-diprenorphine binding was found between DYT1-PTD and controls, and no correlation between the severity of dystonia and opioid binding was seen. We conclude that aberrant opioid transmission is unlikely to be present in DYT1-PTD and altered opioid transmission is not a common mechanism underlying all disorders of involuntary movement.  相似文献   
153.
The objective of this study was to compare the clinical and laboratory consequences of left and right displacement of the abomasum (LDA and RDA), short‐ and long‐term survival after surgery and the findings in cows, that could not be cured by omentopexy. Data from 564 cases of displaced abomasum (466 LDA, 98 RDA) were analysed retrospectively. Clinical and laboratory findings were compared between the two manifestations of DA. Survival was assessed after 10 days and after 15 months. Necropsy was carried out on cows that died or were killed. On arrival at the clinic, left displacement of the abomasum (LDA) cows had been recognized as diseased for longer. LDA occurred earlier in lactation, and more cows with right displacement of the abomasum (RDA) were pregnant. Overall clinical symptoms were more severe in RDA than in LDA cows. Heart rate was higher, body temperature was lower, inanition, abnormal faeces and ruminal stasis were more frequent in RDA cows. Leucocyte counts were higher, and potassium and chloride levels were lower in RDA cows. Acetonuria was more frequent in LDA cows. More LDA than RDA cows were released from the clinic as cured (82.0% versus 74.5%). However, survival after the early post‐surgical period was similar for RDA and LDA cows. At necropsy, diseases of the gastrointestinal system were the predominant finding in RDA cows, while in LDA cows, diseases of the liver and other concurrent diseases were more important.  相似文献   
154.
Various diseases of the central nervous system are characterized by induction of inflammatory events, which involve formation of prostaglandins. Production of prostaglandins is regulated by activity of phospholipases A(2) and cyclooxygenases. These enzymes release the prostaglandin precursor, the n-6 polyunsaturated fatty acid, arachidonic acid and oxidize it into prostaglandin H(2). Docosahexaenoic acid, which belongs to the n-3 class of polyunsaturated fatty acids, was shown to reduce production of prostaglandins after in vivo and in vitro administration. Nevertheless, the fact that in brain tissue cellular phospholipids naturally have a uniquely high content of docosahexaenoic acid was ignored so far in studies of prostaglandin formation in brain tissue. We consider the following possibilities: docosahexaenoic acid might attenuate production of prostaglandins by direct inhibition of cyclooxygenases. Such inhibition was found with the isolated enzyme. Another possibility, which has been already shown is reduction of expression of inducible cyclooxygenase-2. Additionally, we propose that docosahexaenoic acid could influence intracellular Ca(2+) signaling, which results in changes of activity of Ca(2+)-dependent phospholipase A(2), hence reducing the amount of arachidonic acid available for prostaglandin production. Astrocytes, the main type of glial cells in the brain control the release of arachidonic acid, docosahexaenoic acid and the formation of prostaglandins. Our recently obtained data revealed that the release of arachidonic and docosahexaenoic acids in astrocytes is controlled by different isoforms of phospholipase A(2), i.e. Ca(2+)-dependent phospholipase A(2) and Ca(2+)-independent phospholipase A(2), respectively. Moreover, the release of arachidonic and docosahexaenoic acids is differently regulated through Ca(2+)- and cAMP-dependent signal transduction pathways. Based on analysis of the current literature and our own data we put forward the hypothesis that Ca(2+)-independent phospholipase A(2) and docosahexaenoic acid are promising targets for treatment of inflammatory related disorders in brain. We suggest that Ca(2+)-independent phospholipase A(2) and docosahexaenoic acid might be crucially involved in brain-specific regulation of prostaglandins.  相似文献   
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158.
This study provides an overview of the papers emanating from the experimental trial that evaluated a new cognitive rehabilitation program in older adults who were experiencing normal cognitive decline. The main features of the design are summarized, along with evidence that the training produced long-lasting improvement in memory performance, goal management, and psychosocial status. The benefits were attributed to several factors, including the program's emphasis on techniques that promoted efficient strategic processing. Limitations of the program and directions for future research are discussed.  相似文献   
159.
The primary goal of this study was to identify secondary functional changes in the peripheral motor units of the paretic upper extremity (UE) in patients with severe ischemic stroke and to determine how these changes develop during the first weeks after stroke. An inception cohort of 27 consecutive patients with an acute ischemic supratentorial stroke and an initial UE paralysis was compared with 10 healthy control subjects. The ulnar nerve was electrically stimulated proximal to the wrist and electromyographic recordings were obtained from the abductor digiti minimi muscle. Hemiparetic side mean values of the compound muscle action potential (CMAP) 1 and 3 weeks after stroke were compared with the nonparetic side and with CMAP values obtained from healthy control subjects. The mean CMAP amplitude in patients was significantly lower on the paretic side compared with the nonparetic side and with control subjects. Decrease in CMAP amplitude was observed in more than half of the stroke patients, sometimes as early as 4 days after stroke, and persisted in most cases. Whenever present, it was accompanied by absence of motor recovery at that specific time after stroke. Decreased CMAP amplitude in the abductor digiti minimi muscle can be seen already in the very acute phases after stroke unrelated to peripheral neuropathy, radiculopathy, or plexopathy, and it is accompanied by absence of UMN recovery. This knowledge is important for interpreting electrophysiological data in stroke patients.  相似文献   
160.
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