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41.
Background: Although a positive inotropic effect of hypertonic saline has been demonstrated in isolated cardiac tissue as well as in animal preparations, no information exists about a possible positive inotropic action of hypertonic saline in humans. The aim of this investigation was to determine whether a clinically relevant positive inotropic effect can be demonstrated in humans.

Methods: Twenty-six patients without cardiovascular disease were randomized to receive 4 ml/kg of either 7.2% hypertonic saline/6% hetastarch or 6% hetastarch (control) at a rate of 1 ml *symbol* kg sup -1 *symbol* min sup -1 while under general endotracheal anesthesia. Transesophageal echocardiography was used to evaluate left ventricular function. Arterial pressure, heart rate, and left ventricular end-systolic and end-diastolic diameter, area, and wall thickness were measured immediately before and after administration of either solution. Fractional area change, end-systolic wall stress, and the area under the end-systolic pressure-length relationship curve (ESPLRarea) were calculated. ESPLRarea was used to assess left ventricular contractility.

Results: Administration of hypertonic saline/hetastarch resulted in a significant decrease of mean arterial pressure and end-systolic wall stress from 77 plus/minus 14 (mean plus/minus SD) to 64 plus/minus 17 mmHg (P < 0.01) and from 52 plus/minus 14 to 32 plus/minus 11 103 dyne/cm2 (P > 0.01), respectively. End-diastolic area and fractional area change increased from 16.5 plus/minus 2.9 to 21.7 plus/minus 3.3 cm2 (P < 0.01) and from 0.53 plus/minus 0.07 to 0.70 plus/minus 0.06 (P < 0.01), respectively, whereas there was only a minor change of ESPLRarea from 38 plus/minus 13 to 44 plus/minus 13 mmHg.cm (P < 0.05).  相似文献   

42.
Surgical Principles The lateral approach is routinely combined with an osteotomy of the greater trochanter. We resect the newly formed callus located at the anterior, posterior and caudal aspect of the femoral neck distal to the epiphysis. No shortening of the femoral neck results from this procedure. One can safely avoid a vascular injury by performing a careful dissection, since the posteriorly reflected articular capsule containing the nutrient vessels to the head is detached from the femoral neck like a banana peel. The resection manoeuvre is performed next to the physeal plate of the slipped epiphysis. After callus resection, reduction of the femoral head by longitudinal traction and internal rotation of the limb is easy. The aim is complete correction of the slippage. When there is excess physeal cartilage, we resect it with a curette and then the head is fixed using 2 screws. Revised Version from: Operat. Orthop. Traumatol. 4 (1992), 77–85 (German Edition).  相似文献   
43.
Zusammenfassung Der richtige Zeitpunkt für das Absetzen der Antiepileptika (AE) im Kindesalter ist unbekannt. Anl?sslich ihrer Jahrestagung haben die Mitglieder des K?nigsteiner Arbeitskreises (KA) eigene und publizierte Absetzstrategien diskutiert. Da Studien zu diesem Thema rar und widersprüchlich sind, wurde beschlossen, die Diskussionsergebnisse im Sinne einer Meinungs?u?erung zu publizieren. Bei Neugeborenen besteht übereinstimmung, AE innerhalb von 2 bis 12 Wochen nach dem letzten Anfall abzusetzen. Bei BNS-Epilepsie wird Vigabatrin nach 6 bis 12 und Sultiam nach 6 bis 36 Monaten abgesetzt. Nach erfolgreicher Steroidtherapie setzt die Mehrheit des KA die AE-Therapie für zwei Jahre fort. Für die Rolando-Epilepsie sind 1 bis 3 Jahre Anfallsfreiheit ausreichend, auch wenn fokale Spike-Waves persistieren. Im Falle einer symptomatisch fokalen Epilepsie ist die Grunderkrankung mitentscheidend für das Absetzen. Die Behandlung der Absencen-Epilepsie kann nach zwei Jahren beendet werden, w?hrend bei myoklonisch- astatischer Epilepsie meist eine 2- bis 5-j?hrige Anfallsfreiheit vorausgesetzt wird. Konsens besteht darüber, dass die Juvenile- Myoklonus-Epilepsie ein sehr hohes Rückfallrisiko birgt. Dennoch ziehen einzelne neurop?diatrische Mitglieder einen Absetzversuch nach 2- bis 3-j?hriger Anfallsfreiheit in Betracht. Die überwiegende Mehrheit des KA führt aber bei gesicherter Diagnose keinen Absetzversuch durch. Bezüglich der Absetzgeschwindigkeit wird ein langsames (3 bis 12 Monate) Ausschleichen favorisiert. Nur zwei Mitglieder praktizieren ein rascheres Absetzen (<3 Monaten). Das EEG spielt für die Entscheidung eine untergeordnete Rolle und bleibt auf bestimmte Epilepsieformen (z. B. Absencen-Epilepsie) beschr?nkt. Das vorliegende Papier gibt die Meinung des KA wieder und eignet sich nicht im Sinne einer Leitlinie. Für die Entscheidung AE abzusetzen, ist immer eine individuelle Abw?gung von Grunderkrankung, Epilepsieform und psychosozialen Umst?nde erforderlich.   相似文献   
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Prehospital emergency medicine in Germany is based on a specially trained physician-staffed system, in order to realize a differentiate therapy at the scene. In the last years, the special education and the qualification were more and more discussed after the determination of deficits in the prehospital management of special emergency situations. In the presented paper we described the concept and organization of a practice-oriented training model of invasive emergency techniques, as like as the emergency cricothyrotomy, the thoracic tube and the intraosseous access. The relevance and the efficacy are discussed based on an evaluation of the participants. Practice-oriented training models seem to be adequate instruments in order to close the leak in educational programs and can help to improve the qualification of the physician-staffed system, generally.  相似文献   
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Patients after kidney, heart and lung transplantation differ in their immunosuppressive drug regimens and in susceptibility to infectious complications with cytomegalovirus (CMV). In this study, CMV-specific T-cell responses were characterized in long-term transplant recipients and associated with the frequency of infectious complications. CMV-reactive CD4 T cells from 50 healthy controls, 68 renal, 14 heart and 24 lung transplant recipients were flow cytometrically quantified by the induction of cytokines after specific stimulation. Moreover, the immunosuppressive effect of calcineurin inhibitors on specific T-cell reactivity was quantified in vitro and compared with responses in vivo. Median CMV-specific T-cell frequencies in long-term renal (1.48%; range 0.06-17.26%) and heart transplant recipients (0.90%; 0.13-12.49%) did not differ from controls (1.82%; 0.26-21.00%). In contrast, CMV-specific T-cell levels were significantly lower in lung transplant recipients (0.50%; <0.05-4.98%) and showed a significant correlation with the frequency of infectious episodes (r =-0.57, p = 0.005). The differences within the groups were associated with increasing dosages of immunosuppressive drugs, as exemplified for calcineurin inhibitors that dose dependently reduced specific T-cell reactivity in vitro. In conclusion, monitoring CMV-specific CD4 T cells may serve as a measure for long-term disease susceptibility and may contribute to an improved management of CMV complications after lung transplantation.  相似文献   
49.
4 patients with a mean age of 20 years and isolated congenital radial head dislocation (1 unilateral anterior, 1 unilateral posterior and 2 bilateral anterior dislocations) were all pain-free and had almost normal elbow function.  相似文献   
50.
Two recently discovered genes, the recombination activating genes 1 and 2 (RAG-1 and RAG-2), are necessary to perform variable (V), diversity (D), and joining (J) recombination. They synergistically activate VDJ recombination to generate immunocompetent lymphocytes. Disruption of either gene results in a maturation arrest at a very early B and T cell progenitor stage. Expression and downregulation of RAG's are closely associated with interleukin 7, sIgM and TCR-CD3 complex, respectively. Assessment of RAG mRNA expression is a valuable marker in identifying the genotypic maturation status of leukemias and lymphomas. Persistent RAG expression in otherwise mature lymphoid proliferations may explain puzzling biological and clinical observations such as multiple rearrangements in lymphomas with a mature phenotype. Lack of RAG expression in Hodgkin's disease with abundant Reed-Stern-berg cells is consistent with a mature phenotype of the latter. Availability of a anti-RAG-1 monoclonal antibody in the near future will facilitate RAG analysis of lymphomas.  相似文献   
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