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11.
A knowledge of the alteration in the fibre type profile of paraspinal muscle associated with low back pain is essential for the design of successful rehabilitation programmes. In attempting to compare the muscles of patients with low back pain with those of controls, few previous studies have considered factors such as gender, age, and size of the subjects, each of which can potentially confound interpretation of the results. We obtained samples of lumbar paraspinal muscle during spinal surgery from 21 patients with low back pain and, using the percutaneous biopsy technique, from 21 control volunteers matched for gender, age, and body mass. The samples were subject to routine histochemicsl typcal analysis to determine characteristics of muscle fibre type. Compared with controls, the muscle of the patients had a significantly higher proportion of type-IIB (fast-twitch glycolytic) fibres than type- I (slow oxidatve) fibres. The mean size of a given fibre type did not differ between the patients and the controls. Consequently, the relative area of the muscle iccupied by type-IIB fibres was higher and that by type-I fibres Was lower in the patients. The patients had a greater number of muscle samples with more than 1% type-IIC fibres, and abnormalities that could be described as pathological were more marked in the patients than in the controls. In conclusion, the paraspinal muscles of patients who have low back pain display a more glycolytic (faster) profile; this can be expected to render them less resistant to fatigue.  相似文献   
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Deep brain stimulation of the subthalamic nucleus (STN-DBS) is an established therapy for Parkinson's disease (PD). A manic episode with psychotic symptoms induced by STN-DBS occurred in a previously psychiatrically healthy patient, focusing on the role of STN-DBS in influencing not only motor but also emotional behaviour.  相似文献   
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In order to analyze the epileptogenic mechanisms of caffaine and related xanthines, putative effects of these drugs were studied on adenosine receptors of CA3 neurons in hippocampal slices. Epileptogenic concentrations of different xanthine derivatives strongly correlated with their affinities for the inhibitory A1 adenosine receptor subtype. The A1 receptor agonists adenosine and R-PIA reversibly depressed xanthine-induced epileptic activity without effects on the resting membrane potential or on spontaneously occuring action potentials. These findings suggest that the epileptogenic potency of xanthines is primarily due to the blockade of the A1 receptors through an abnormal rise of intracellular cAMP and to the excessive transmembrane calcium fluxes underlying paroxysmal depolarization shifts.  相似文献   
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Zusammenfassung Hintergrund: Die Assoziation zwischen Helicobacter-pylori-(H.-pylori-)Infektion und Dyspepsie wird kontrovers diskutiert. Im Rahmen der BASF-H.-pylori-Vorsorgeaktion wurde u. a. die Prävalenz von Dyspepsie bei arbeitsfähigen Personen ermittelt sowie der Zusammenhang mit der H.-pylori-Infektion und der Erfolg einer Eradikationstherapie untersucht. Probanden und Methodik: 6 132 Beschäftigte der BASF wurden untersucht und im Rahmen einer standardisierten Anamnese u. a. zu dyspeptischen Beschwerden befragt. Diese wurden entsprechend der führenden Symptomatik den Dyspepsiesubtypen vom Ulkustyp, Dysmotilitätstyp, Refluxtyp und unspezifischen Typ zugeordnet. Bei allen Beschäftigten wurde die Seroprävalenz (IgG-ELISA) der H.-pylori-Infektion bestimmt. Allen H.-pylori-positiven Personen mit Dyspepsie wurde weitere Diagnostik in Form einer Ösophagogastroduodenoskopie und einer Sonographie des Abdomens bei Fachärzten empfohlen und eine H.-pylori-Eradikationstherapie (Italian-Triple-Therapie) angeboten. In einer Untergruppe endoskopisch untersuchter Beschäftigter mit peptischer Ulkuskrankheit (PUD, n = 37) bzw. Non-Ulcer-Dyspepsie (NUD; n = 39) wurde der prognostische Wert der im Western Blot ermittelten Antikörper gegen CagA und VacA untersucht. Ergebnisse: 1 255 der 6 143 Beschäftigten (20,4%) berichteten über Dyspepsie. 492 Personen mit Dyspepsie (39,2%) waren gleichzeitig H.-pylori-positiv. Bei Personen ohne dyspeptische Symptome betrug die H.-pylori-Prävalenz 35,8%. Personen mit unterschiedlichen Dyspepsiesubtypen unterschieden sich nicht hinsichtlich der H.-pylori-Prävalenz. Personen, die häufige und intensive dyspeptische Beschwerden angaben, waren allerdings signifikant häufiger H.-pylori-positiv (OR 2,09, CI 1,43-3,05). Die Seroprävalenz von CagA und VacA bei Personen mit PUD unterschied sich nicht signifikant von derjenigen bei Personen mit NUD. 458 H.-pylori-positiven Personen wurde die Eradikation empfohlen. 330 Personen (72,1%) folgten der Empfehlung. 128 (27,9%) ließen sich nicht behandeln. An der Nachkontrolle nach 12 Monaten nahmen 402 Personen (87,8%) teil, davon waren 300 behandelt, 102 nicht. Der serologisch analysierte Eradikationserfolg lag bei 81,5%. 42,8% der erfolgreich behandelten Personen berichteten über Besserung ihrer Beschwerden, 33,2% über Beschwerdefreiheit. Bei den nicht behandelten Personen war dies nur in 16,7% bzw. in 37,3% der Fall. Vermehrte Refluxbeschwerden traten nach erfolgreicher Eradikation nicht auf. Schlussfolgerung: Wir konnten keinen generellen Zusammenhang zwischen Dyspepsie und H.-pylori-Infektion in einem großen Kollektiv arbeitsfähiger Personen erkennen. Häufige und intensive dyspeptische Symptome scheinen allerdings ein prädikativer Faktor für die H.-pylori-Seropositivität zu sein. Die serologisch bestimmbaren Virulenzfaktoren tragen nicht zur Unterscheidung PUD oder NUD bei. Die Eradikationstherapie führte nach 1 Jahr zwar häufiger zur Besserung, aber nicht häufiger zu Beschwerdefreiheit bei Beschäftigten mit dyspeptischen Beschwerden im Vergleich zu unbehandelten Personen. Abstract Background: The role of Helicobacter pylori (H. pylori) infection in dyspepsia is controversial. In the course of a health initiative within a large industrial corporation, we investigated the prevalence of both dyspepsia and positive H. pylori serology and the outcome of eradication therapy in symptomatic H. pylori positive employees. Test Persons and Methods: H. pylori serology (IgG ELISA) was determined in 6,143 employees of BASF AG Ludwigshafen/Germany who were also asked to complete a standardized health history administered by a physician. Peptic ulcer disease (PUD) and dyspepsia subgroups were defined based on past medical history and symptom profiles using the criteria of Heading. Upper GI endoscopy, abdominal ultrasound and eradication therapy (Italian Triple Therapy) was recommended for symptomatic H. pylori positive individuals. The prognostic value of antibodies against CagA and VacA was evaluated in 37 and 39 employees with PUD and non-ulcer dyspepsia (NUD) confirmed by endoscopy, respectively. Results: Of 6,143 employees, 1,255 (20.4%) were classified as dyspeptic, 492 (39.2%) of whom were H. pylori positive. The seroprevalence of H. pylori in asymptomatic employees was 35.8%. There were no significant differences in H. pylori seroprevalence among dyspepsia subgroups (reflux only, dysmotility only, reflux/dysmotility, ulcer-like and non-specific). However, individuals reporting severe dyspeptic symptoms were significantly more likely to be H. pylori positive (OR 2.09, CI 1.43-3.05). The seroprevalence of CagA and VacA was not significantly different among employees with NUD compared to referents or among employees with NUD compared to those with PUD. 330 (72%) of 458 employees with dyspepsia received eradication therapy, 128 persons refused therapy. Based on a 12-month follow-up of 402 individuals (300 of whom had received therapy), eradication success was 81.5% as judged by serology. Of the successfully treated employees, 33.2% reported a total absence and 42.8% reported a decrease in symptoms. Among the employees who refused therapy, the corresponding percentages were 37.3% and 16.7%, respectively. An increase in reflux complaints was not observed among treated employees. Conclusion: In a large active employee population, at most a very weak association was observed between the prevalence of H. pylori seropositivity and dyspepsia. Frequent and severe dyspeptic symptoms were associated with an increased rate of H. pylori seropositivity. The analysis of the virulence factors is not particularly helpful in discriminating PUD or NUD. Eradication of H. pylori infection leads to a decrease in dyspeptic symptoms after 12 months, but not more often to their complete absence compared to untreated individuals.  相似文献   
16.
The hypothesis was tested that an initial lithium-tricyclic antidepressant (TCA) combination has a better antidepressant effect than standard TCA treatment in non-refractory depression at the beginning of an episode. Twenty bipolar melancholic type depressed inpatients under lithium-TCA treatment were compared with 20 patients with the same diagnosis and TCA-placebo treatment for 5 weeks under double-blind conditions. All patients were male. Initial lithium-TCA treatment reduced depressive symptoms significantly more than antidepressant treatment with TCA and placebo after 5 weeks, but not in weeks 1 or 2. It can be concluded that lithium augmentation of TCA treatment should be started even at the beginning of antidepressant TCA treatment to provide a better treatment response in those patients who will profit from long-term lithium prophylaxis, e.g. bipolar patients with melancholic type depression.  相似文献   
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This study of a series of 40 mildly head injured (concussed) patients suggests that different physiologic pathways underlying the tests done in a six-part resting EEG, and for the 11 evoked electrical potential shifts occurring in the cerebral terrain, are testable. Further work seems likely in order to ascertain which clinical signs and symptoms may be related to specific individual types of recorded electronic brain imaging (EBI) abnormality. Which of the 11 parameters studied, EEG, VER, AER, and SER, would be more or less likely to be abnormal in their individual patterns (as being deviant from normal controls) also remains to be defined. The relationship of these neurophysiologic abnormalities to certain postconcussive symptoms, i.e., headache, dizziness, blurred vision, etc., at this point in time remains to be evaluated more precisely. The authors suggest that further research is necessary in evaluating the clinical use of somatosensory evoked responses as an additional parameter in electronic brain imaging (EBI) technology.  相似文献   
19.
Background: Measuring the work of breathing of patients undergoing spontaneous assisted ventilation can be useful to monitor and titrate ventilatory support. The aim of this study was to obtain measurements of the pressure generated by the respiratory muscles (PMUSC) and the derived pressure-time product (PTP; a good indicator of the metabolic work of breathing), performing the rapid interrupter technique with a commercial ventilator.

Methods: A Draeger Evita 4 ventilator (Draeger Medical, Lubeck, Germany) was controlled by a personal computer to rapidly interrupt the airway flow at different times and volumes of the respiratory cycle during pressure-support ventilation. From the airway pressure tracing after the occlusion, the authors estimated the alveolar pressure and PMUSC; the integration of PMUSC values over the inspiratory time yields the measurement of PTP. Esophageal pressure measurements were used as a reference. After a bench study of the valves' performance, the authors performed 11 measurement sequences in eight patients.

Results: The closure times for the inspiratory and expiratory valves were 74 +/- 10 and 61 +/- 13 ms, respectively. The interrupter technique provided a reliable estimate of PMUSC (PMUSC, occl = 1.00 [middle dot] PMUSC, pes + 0.19; r = 0.88; 95% confidence interval for agreement, +5.49/-5.32 cm H2O). PTPoccl tightly correlated with PTPpes (PTPoccl = 0.95 [middle dot] PTPpes + 0.13; r = 0.96; 95% confidence interval, 1.94/-1.61 cm H2O [middle dot] s).  相似文献   

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