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991.
Cell culture-based influenza vaccine manufacturing is of growing importance. Depending on virus strains, differences in infection dynamics, virus-induced apoptosis, cell lysis and virus yields are observed. Comparatively little is known concerning details of virus–host cell interaction on a cellular level and virus spreading in a population of cells in bioreactors. In this study, the infection of MDCK cells with different influenza A virus strains in lab-scale microcarrier culture was investigated by flow cytometry. Together with the infection status of cells, virus-induced apoptosis was monitored. A mathematical model has been formulated to describe changes in the concentration of uninfected and infected adherent cells, dynamics of virus particle release (infectious virions, hemagglutinin content), and the time course of the percentage composition of the cell population. 相似文献
992.
The pharmacokinetics of opioids are impaired in patients with liver and renal failure. Fentanyl, sufentanil, and alfentanil are metabolized in the liver. The extrahepatic metabolism by renal enzymes is gaining more importance in patients with severe liver disease. Pharmacokinetic effects of single doses of fentanyl and sufentanil are not affected in liver and renal failure; however, continuous infusion of fentanyl may result in accumulation and prolonged opioid effects. Plasma clearance and elimination of alfentanil are reduced in patients with liver failure and its clinical use can therefore not be recommended. A reduction in alfentanil dosing is not necessary in patients with renal failure. Remifentanil is the opioid of choice in patients with liver and renal failure. The clearance of morphine is reduced in liver failure. In renal failure an accumulation of morphine metabolites has been demonstrated, and thus, application of morphine is not recommended in patients with liver and renal failure. A reduction in piritramide dosing is necessary in patients with liver failure. 相似文献
993.
994.
Björn-Christian Link Emre F. Yekebas Dean Bogoevski Asad Kutup Gerhard Adam Jakob R. Izbicki Gerrit Krupski 《Journal of gastrointestinal surgery》2007,11(2):166-170
Symptomatic biliary leakage following major upper abdominal surgery is a severe complication resulting in increased morbidity
and mortality. Treatment options usually include either endoscopic intervention or surgical revision. These options may be
burdened by a high perioperative risk for the patient (e.g., patients with severe disease) or simply may not be possible (e.g.,
nonpreserved gastroduodenal passage). In the past, percutaneous transhepatic cholangiodrainage did only seem to be a viable
option for patients with dilated bile ducts. Here, we present our experience in a consecutive series of patients with symptomatic
biliary leakage following major upper abdominal surgery and without dilation of the biliary system that underwent percutaneous
transhepatic cholangiodrainage. Percutaneous transhepatic cholangiodrainage was feasible in 15 of 18 patients (83.3%). The
procedure was technically not possible in three patients (16.7%). In 10 of the 15 patients (66.6%) with feasible percutaneous
transhepatic cholangiodrainage, biliary leakage was definitely controlled without the need for surgical revision. Depending
on the experience with the interventional procedure, percutaneous transhepatic cholangiodrainage should be considered as an
alternative for treatment of symptomatic biliary leakage instead of immediate reoperation.
Presented at the Digestive Disease Week 2005 (DDW), Chicago, IL, May 14–19, 2005 (poster presentation). 相似文献
995.
Abstract Aggressive behaviour is rarely observed as an ictal semiology. Ictal aggression can occur in lesions of frontal and limbic
structures. In limbic structure lesions, the main mechanism of aggressive behaviour is hyperactivity; whereas frontal lesions
may cause aggressive behaviour with an indirect mechanism in which the suppression on limbic system is lost. Here we present
a patient with ictal aggression. In this case a right frontoparietal epileptiform focus was detected during the postictal
period. Magnetic resonance imaging showed cortical dysplasia on the right inferior frontal gyrus. The seizures disappeared
completely after pharmacological treatment. 相似文献
996.
Prof. Dr. Rüdiger Köhling 《Zeitschrift für Epileptologie》2007,20(1):1-14
Zusammenfassung
Die Epilepsieforschung ist kein neues wissenschaftliches Feld—klinische und experimentelle Untersuchungen werden seit Jahrzehnten
betrieben. Trotz dieser fortw?hrenden Bemühungen sind die Pathomechanismen der Epilepsie letztlich nicht vollst?ndig gekl?rt—allerdings
gelangen in den letzten Jahren auch beachtliche Fortschritte. Vor allem durch die Kombination genetischer, molekularer und
funktioneller Analysen konnten wichtige Teilaspekte der Entstehungsprozesse der Epilepsie aufgekl?rt werden. Der vorliegende
übersichtsartikel soll nach einer kurzen Er?rterung der grunds?tzlichen Faktoren der Erregbarkeit einzelner Zellen und des
neuronalen Zellverbandes in fünf kurzen Kapiteln einen überblick über den aktuellen Forschungsstand liefern. Innerhalb der
ersten drei Abschnitte werden Ver?nderungen spannungsabh?ngiger Str?me, der synaptischen Transmission und deren Modulation
sowie der Expression von Gap junctions beleuchtet. Darüber hinaus widmet sich ein Abschnitt morphologischen Ver?nderungen.
Der letzte Teil behandelt Aspekte spezifischer genetischer Syndrome.
Dieser Beitrag ist bereits in verkürzter Form in der Zeitschrift „Klinische Neurophysiologie“, Bd. 37 (2006), S. 1–9, unter
dem Titel „Pathophysiologie der Epilepsie“ erschienen. 相似文献
997.
J Rymaszewska J Jarosz-Nowak A Kiejna T Kallert M Schützwohl S Priebe D Wright P Nawka J Raboch 《European psychiatry》2007,22(3):160-166
ObjectiveTo assess the social disability of people with different psychiatric disorders.MethodsCross-site survey in five psychiatric hospitals (Dresden, Wrocław, London, Michalovce and Prague). Working-aged patients diagnosed (ICD-10) with schizophrenia and related disorders (F2), affective disorders (F3), anxiety disorders (F4), eating disorders (F5) and personality disorders (F6), were assessed at admission (n = 969) and 3 months after discharge (n = 753) using the Brief Psychiatric Rating Scale and the Groningen Social Disability Schedule. The main outcome measure was Interviewer-rated social disability.ResultsDuring acute episodes patients with personality, eating and schizophrenic disorders functioned less effectively than those with affective or anxiety disorders. After controlling for age and severity of psychopathology, there was no significant effect of the diagnosis (during remission), sex, education and history of disorder on disability. Site, employment and partnership were significant factors for the level of social disability in both measure points.ConclusionSeverity of psychopathological symptoms, not the diagnosis of a mental disorder, was the most significant factor in determining the level of social functioning, particularly during the remission period. Site, employment and partnership appeared as significant factors influencing the level of social disability. 相似文献
998.
Eight-channel transmit/receive body MRI coil at 3T. 总被引:1,自引:0,他引:1
P. Vernickel P. Röschmann C. Findeklee K.‐M. Lüdeke Ch. Leussler J. Overweg U. Katscher I. Grässlin K. Schünemann 《Magnetic resonance in medicine》2007,58(2):381-389
Multichannel transmit magnetic resonance imaging (MR) systems have the potential to compensate for signal-intensity variations occurring at higher field strengths due to wave propagation effects in tissue. Methods such as RF shimming and local excitation in combination with parallel transmission can be applied to compensate for these effects. Moreover, parallel transmission can be applied to ease the excitation of arbitrarily shaped magnetization patterns. The implementation of these methods adds new requirements in terms of MRI hardware. This article describes the design of a decoupled eight-element transmit/receive body coil for 3T. The setup of the coil is explained, starting with standard single-channel resonators. Special focus is placed on the decoupling of the elements to obtain independent RF resonators. After a brief discussion of the underlying theory, the properties and limitations of the coil are outlined. Finally, the functionality and capabilities of the coil are demonstrated using RF measurements as well as MRI sequences. 相似文献
999.
1000.