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To improve the diagnostic accuracy of electroencephalography (EEG) criteria for nonconvulsive status epilepticus (NCSE), external validation of the recently proposed Salzburg criteria is paramount. We performed an external, retrospective, diagnostic accuracy study of the Salzburg criteria, using EEG recordings from patients with and without a clinical suspicion of having NCSE. Of the 191 EEG recordings, 12 (12%) was classified as an NCSE according to the reference standard. In the validation cohort, sensitivity was 67% and specificity was 89%. The positive predictive value was 47% and the negative predictive value was 95%. Ten patients in the control group (n = 93) were false positive, resulting in a specificity of 89.2%. The interrater agreement between the reference standards and between the scorers of the Salzburg criteria was moderate; disagreement occurred mainly in patients with an epileptic encephalopathy. The Salzburg criteria showed a lower diagnostic accuracy in our external validation study than in the original design, suggesting that they cannot replace the current practice of careful weighing of both clinical and EEG information on an individual basis.  相似文献   
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The thiadiazinone derivative [+]-EMD 60263 ((+)-5-(1-(α-ethylimino-3,4-dimethoxybenzyl)-1,2,3,4- tetrahydroquinoline-6-yl)-6-methyl-3,6-dihydro-2H-1,3,4 -thiadiazine-2-on) is a Ca2+-sensitizing agent with only minor phosphodiesterase inhibitory activity. Our aim was to characterize the inotropic and electrophysiological effects of [+]-EMD 60263 and its enantiomer [-]-EMD 60264 in several cardiac muscle preparations. The Ca2+-sensitizing activity resided in the [+]-enantiomer only. [+]-EMD 60263 (3 μM) shifted the EC50 of Ca2+ for contractile activation of skinned fibers of pig heart from 2.41 μM to 0.73 μM, whereas [-]-EMD 60264 (30 μM) was ineffective. In Langendorff-perfused guinea pig hearts, [+]-EMD 60263 and [-]-EMD 60264 induced concentration-dependent positive and negative inotropic effects, respectively; both enantiomers reduced spontaneous heart rate but did not influence perfusion pressure. The maximum increase in force of human atrial trabeculae was 35 % of pre-drug control with [+]-EMD 60263 in comparison to 113 % with forskolin. In guinea-pig papillary muscles, [+]-EMD 60263 and [-]-EMD 60264 had opposite inotropic responses, however, both agents similarly prolonged action potential duration. Both enantiomers concentration-dependently blocked the rapidly activating component IKr of the delayed rectifier in guinea-pig myocytes. The block saturated at potentials positive to +30 mV, closely resembling the effects of the antiarrhythmic agent E-4031 which had been originally used to define IKr. It is concluded, that the positive inotropic action of [+]-EMD 60263 can be explained by prevalence of the Ca2+-sensitizing effect. The accompanying prolongation in action potential duration is caused by block of the IKr component of the delayed rectifier. While the inotropic effects are stereoselective, most of the electrophysiological actions are clearly independent of sterical configuration. The combination of Ca2+-sensitizing with class-III antiarrhythmic action may provide an interesting pharmacological profile of potential therapeutic use. Received: 7 January 1997 / Accepted: 25 February 1997  相似文献   
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INTRODUCTIONThemicrotubule-associatedprotein蚲ishyperphos-phorylatedandglycosylatedinAlzheimerdisease(AD),andtheseabnormalmodificationsformedthebasisofprogressivelyretrogradeneurofibrillarydegenerationseeninADbrainandtherebythedementia(1,2).ADab-normallyphosphorylated蚲notonlyismicrotubuleas-semblyincompetent,butalsoinhibitsassemblyanddis-assemblesthepreassembledmicrotubulesinvitro(3).Inthetangle-bearingneuronsinADbrain,thenormalcytoskeletonisdisruptedandreplacedwi…  相似文献   
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In a prospective, randomized trial, 104 consecutive patients with displaced femoral neck fractures were allocated either to fixation with a sliding screw plate or 4 ASIF cancellous bone screws. The patients were reexamined at fixed intervals to determine the time of union. The 2-year-cumulated rate of union was 64 per cent in the plate group and 84 per cent in the screw group.  相似文献   
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OBJECTIVE: The aim of this paper is to assess the accuracy of an algorithm implemented by PRAXIM in the SURGETICS navigation station for detection of the hip center. This study will assess the robustness and accuracy of the algorithm in various clinical situations such as those involving non-sphericity of the femoral head, motion of the pelvis during hip center detection, and restricted range of motion. MATERIALS AND METHODS: The localization of the hip center, based on kinematics, relies on the recording of n successive positions of the femoral rigid body in the localizer reference system during a passive circumduction motion of the hip joint. Therefore, the shape of the clouds of points acquired may vary from one acquisition to the next. To allow a comprehensive study of the consequences of these variations for hip center detection, we developed a simulator to generate numerous clouds of points. Results given subsequently for each test are the values of the difference between the femoral mechanical axis computed with C(c), the computed hip center, and the same axis computed with C(o), the reference hip center. RESULTS: Test 1: Sensitivity to noise. The errors ranged from 3.33 E - 12 (SD 3.29E - 12) for a noise of 0 mm to 8.18E - 1 (SD - 7.05E - 1) for a noise of 15 mm. Test 2: Sensitivity to the shape of the acquisition motion. All trajectories gave an error < 1 degrees . Test 3: Sensitivity to restricted range of motion. No value > 1 degrees was found during this test. Test 4: Sensitivity to the distance between two points of the cloud. No value > 0.5 degrees was found during this test. Test 5: Sensitivity to the number of points included in the cloud. No value > 1 degrees was found during this test. CONCLUSIONS: The Surgetics algorithm is robust to noise, can compensate for pelvic motion, and can be used even in the case of restricted range of motion.  相似文献   
8.
Results of three therapeutic modalities used for the treatment of a homogeneous series of patients with a Pouteau Colles fracture are analyzed. Orthopedic treatment provided deceiving results. Pinning was, on the contrary, very effective, intrafocal pinning with immediate mobilization of the wrist appearing perfectly effective. Few complications were reported in contrast to plastered immobilizations. Good results were obtained in 80% of cases and functional recovery was rapid, indicating that this method represents undoubted progress when compared with conventional therapies.  相似文献   
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G12 monoclonal antibody (mAb), one of a library of constructed mAb directed against human sperm proteins, was found by immunoperoxidase staining to label the post-acrosomal and neck regions of fixed human cauda epididymal and ejaculated spermatozoa. Epithelium and fluid of caput epididymis were strongly labelled while there was no staining on testis and efferent ducts. Western lot analysis revealed that G12 antibody reacted with proteins of 17.5, 18 and 19 kDa in human spermatozoa. This pattern seems to be specific for mature human spermatozoa, as it has not been observed either in other human tissues tested, or in spermatozoa from different animals. SOB2, the corresponding protein, was isolated from NP40-extracted human spermatozoa by using preparative electrophoresis, followed by isoelectrofocusing according to its isoelectric point of 6.4 G12 Fab fragments strongly inhibited binding of human spermatozoa to zona-free hamster oocytes (up to 86% inhibition at 200 micrograms/ml). Impairment of binding was dependent on the concentration of purified G12 immunoglobulin (Ig)G1, and significant even at 10 micrograms/ml. There was no inhibitory effect of G12 antibody on sperm motility parameters or triggering of the acrosome reaction and it did not inhibit binding to human zona pellucida. These results indicate that SOB2 is likely to participate in membrane oocyte binding, and my be potential candidate for the development of a contraceptive vaccine.   相似文献   
10.
The cause of many myocardial infarctions is occlusive thrombosis, or a blood clot that stops blood flow in a coronary artery. Hemostasis involves a complex system of factors, which normally form and degrade blood clots, that work within a delicate balance. Emerging evidence suggests that some hemostatic factors, including factor VII, fibrinogen, and plasminogen activator inhibitor-1, are associated with increased risk for cardiovascular disease (CVD). Accumulating evidence suggests a relationship between dietary fatty acids and emerging hemostatic CVD risk factors, although much of this evidence is incomplete or conflicting. Dietary supplementation with marine n-3 fatty acids prolongs bleeding time and may decrease risk for thrombosis. Factor VII coagulant activity modestly decreases with reductions in saturated fatty acid (SFA) intake and thereby may contribute to the beneficial effects of low SFA diets. Large triglyceride-rich particles formed during postprandial lipemia can support the assembly and function of coagulation complexes and seem to play a role in the activation of factor VII, and thus may partially explain increased CVD risk associated with increased postprandial triglyceridemia. As our understanding of the role of dietary fatty acids and hemostasis evolves, it is likely that we will be able to make specific dietary recommendations to further decrease CVD risk. At this juncture, however, increasing marine n-3 fatty acids and decreasing certain SFAs are leading strategies to reduce hemostatic CVD risk factors. An array of dietary strategies that target multiple CVD risk factors could have a greater impact on CVD than a single risk factor intervention strategy.  相似文献   
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