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101.
Chronic pruritus (starting from 6 weeks duration) is symptom of dermatological, internal, neurological or psychiatric disease. Identification and treatment of the underlying diseases is of great importance especially in the initial phase of chronic pruritus in order to prevent peripheral and central sensitization processes and thus chronification. Application of the redefined clinical classification, newly defined clinical algorithms and inquiry of clinical characteristics of pruritus is helpful in finding the underlying disease. In chronic pruritus existing for several years, clarifying the underlying origin is difficult and therapies are often ineffective. Next to conventional therapies such as antihistamines and corticosteroids, central effective substances can be applied preventing pruritus sensation on spinal or cerebral level.  相似文献   
102.
PURPOSE: Frequency potentiation is the increase in force of contraction induced by an increased heart rate (HR). This positive staircase phenomenon has been attributed to changes in Ca2+ entry and loading of intracellular Ca2+ stores. Volatile anesthetics interfere with Ca2+ homeostasis of cardiomyocytes. We hypothesized that frequency potentiation is altered by volatile anesthetics and investigated the influence of halothane (H), sevoflurane (S) and desflurane (D) on the positive staircase phenomenon in dogs in vivo. METHODS: Dogs were chronically instrumented for measurement of left ventricular (LV) pressure and cardiac output. Heart rate was increased by atrial pacing from 120 to 220 beats x min(-1) and the LV maximal rate of pressure increase (dP/dt(max)) was determined as an index of myocardial performance. Measurements were performed in conscious dogs and during anesthesia with 1.0 minimal alveolar concentrations of each of the three inhaled anesthetics. RESULTS: Increasing HR from 120 to 220 beats x min(-1) increased dP/dt(max) from 3394 +/- 786 (mean +/- SD) to 3798 +/- 810 mmHg sec(-1) in conscious dogs. All anesthetics reduced dP/dt(max) during baseline (at 120 beats x min(-1): H, 1745 +/- 340 mmHg x sec(-1); S, 1882 +/- 418; D, 1928 +/- 454, all P < 0.05 vs awake) but did not influence the frequency potentiation of dP/dt(max) (at 220 beats x min(-1): H, 1981 +/- 587 mmHg x sec(-1); S, 2187 +/- 787; D, 2307 +/- 691). The slope of the regression line correlating dP/dt(max) and HR was not different between awake and anesthetized dogs. Increasing HR did not influence cardiac output in awake or anesthetized dogs. CONCLUSION: These results indicate that volatile anesthetics do not alter the force-frequency relation in dogs in vivo.  相似文献   
103.

Background  

Hypertension is one of the major causes of disease burden affecting the Finnish population. Over the last decade, evidence-based care has emerged to complement other approaches to antihypertensive care, often without health economic assessment of its costs and effects. This study looks at the extent to which changes proposed by the 2002 Finnish evidence-based Current Care Guidelines concerning the prevention, diagnosis, and treatment of hypertension (the ACCG scenario) can be considered cost-effective when compared to modelled prior clinical practice (the PCP scenario).  相似文献   
104.
By means of positron emission tomography the uptake and kinetics of N-(methyl-11C)clozapine in different brain regions have been studied in Rhesus monkeys. 11C-clozapine rapidly entered the brain and maximum radioactive uptake was seen 5–12 min after administration. Highest uptake was measured in the striatum. Other regions with an uptake higher than in the cerebellum were thalamus and mesencephalon. The radioactivity from different brain regions decreased with an elimination half-life of about 5 h and parallelled the plasma kinetics of unlabelled clozapine. The striatum/cerebellum ratio of 11C-clozapine-derived radioactivity remained constant during the period studied and did not change after pretreatment with atropine. In contrast, the striatum/cerebellum ratio was somewhat lower after pretreatment with N-methylspiperone (NMSP), indicating competition for the same binding sites in the striatum. After pretreatment with increasing doses of clozapine, a dose-dependent protection of binding sites in the striatum for 11C-NMSP was seen. It is concluded that clozapine is more loosely bound to dopamine receptors in the striatum than N-methylspiperone and that the kinetics of clozapine in the brain parallel that in the plasma. The binding properties of clozapine within the brain may explain some of the clinical properties of the drug.  相似文献   
105.
106.
Radioreceptor assay (RRA) was used to evaluate serum antimuscarinic activity in 10 healthy volunteers after a single dose of scopolamine hydrobromide (ScHBr) solution, 0.02 mg/kg, by a new oral administration method. Cardiac, antisialogogue, and subjective effects of the drug were also recorded. Although clinically useful antisialogogue and sedative effects were obtained 40 to 60 minutes after the administration of ScHBr, no reliable antimuscarinic activity was evaluated in serum samples for up to 3 hours. Clinically useful sedative and antisialogogue effects can be reached by gastrointestinal absorption of ScHBr solution.  相似文献   
107.
A plasmid encoding streptomycin-resistance could be detected in 13 of 32 Pasteurella multocida-cultures isolated from cattle and swine. The plasmid of these cultures proved to be similar upon Southern blot hybridization. It could be transformed into Escherichia coli 490A, where it also expressed streptomycin resistance.  相似文献   
108.
Zusammenfassung Zur Klärung möglicher Ursachenfaktoren, die zur Entstehung einer Laterogenie beitragen, wurden 22 Patienten nach klinisch funktionellen Kriterien ausgewählt und computertomographisch untersucht. Durch die bessere Vergleichbarkeit überlagerungsfrei abgebildeter morphologischer Strukturen im Computertomogramm konnte eine Einteilung in vier Ursachenbereiche erfolgen, innerhalb derer verschiedene asymmetrische Einzelabweichungen analysiert und diskutiert wurden. Es hat sich gezeigt, daß die computertomographisch strukturelle Analyse bei dieser Problemstellung anderen Untersuchungsmethoden überlegen ist und im Einzelfall neue Anhaltspunkte für eine prognostische Abschätzung weiterer Entwicklungstendenzen bietet.
Summary To determine the possible reasons, contributing to the formation of laterogenia, 22 patients were investigated by computer tomography. The patients were selected according to clinical and functional criteria. As CT gives a more accurate comparison of structures without superimposition it was possible to subdivide the causative factors into four groups. Within each of them, different asymmetric deviations could be analysed and discussed. It was shown, that structural-CT analysis is superior to other methods of investigation, particularly for this kind of problem. Furthermore it provides new criteria for a prognostic evaluation of development.

Résumé Pour rechercher les causes qui contribuent à la formation d'une latérogénie, on avait examiné 22 patients, sélectionnés par leur aspect clinique et fonctionnel, à l'aide d'un computer analysant des tomographies. Grâce à ce computer, la meilleure comparaison des structures, représentées sans superposition, donnait la possibilité d'en classifier les causes en quatre catégories, dans lesquelles on analysait et discutait les différentes déviations asymétriques. Il est évident, que dans ces problèmes l'analyse computertomographique-structurelle surpasse d'autres méthodes d'examen et qu'elle offre de nouveaux critères pour prévoir d'autres tendances du développement.
  相似文献   
109.
A new method (ELISA) was used to evaluate the pharmacokinetics of scopolamine following intravenous (0.005 mg/kg), intramuscular (0.01 mg/kg), and oropharyngeal (0.035 mg/kg) administration of the drug to pregnant patients anaesthetized for caesarean section. After intravenous (N = 4) the drug fast disappeared from the circulation with a half-life of about 5 min., and the serum levels generally were measurable up to 3 hours, mean elimination half-life was 1.85 hours. A fast absorption was found after intramuscular injection, tmax = 10 min. (N = 4), and the drug had a clinically significant oropharyngeal absorption as well, tmax was around 1 hour (N = 6). The intramuscular and oropharyngeal, but not the intravenous, administrations produced a marked postoperative sedative and amnesic effects. All three administration ways caused a significant antisecretory action.  相似文献   
110.
BACKGROUND: Knowledge of the prevalence of peripheral arterial disease (PAD) in patients with chronic renal failure (CRF) is limited because of a lack of uniformity in disease definition and recognition. Furthermore, little is known of the prevalence of medial arterial calcification (MAC) in patients with CRF. Our goal is to study the prevalence of PAD and MAC defined by ankle brachial index (ABI) or toe brachial index (TBI) measurements in a Finnish population of patients with CRF consisting of predialysis and dialysis patients, as well as renal transplant recipients. METHODS: We examined 136 patients with CRF and 59 control subjects. Fifty-nine of the patients with CRF had moderate to severe predialysis CRF, 36 patients were on dialysis treatment, and 41 were renal transplant recipients. Mean age of patients was 51.9 +/- 11.5 years, and 39 patients (29%) had diabetes. ABI and TBI were measured by means of photoplethysmography. The definition of PAD required an ABI value of 0.90 or less, a TBI value of 0.60 or less, or a previous positive lower-extremity angiogram result. ABI values of 1.3 or greater or incompressible arteries at ankle level indicated MAC. The presence of claudication was determined by an interview. RESULTS: Prevalences of PAD on this study were 22.0% in patients with predialysis CRF, 30.6% in patients on dialysis treatment, 14.6% in renal transplant recipients, and 1.7% in the control group (P = 0.001). Prevalences of MAC were 23.7%, 41.7%, 23.1%, and 3.4% (P < 0.001), respectively. Only 9 patients had claudication, and 6 of those patients had PAD. CONCLUSION: Both asymptomatic PAD and MAC are common in patients with CRF. Therefore, we recommend the use of both ABI and TBI measurements in the evaluation of PAD in patients with CRF.  相似文献   
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