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101.
A new noninvasive cardiac output (CO) computer ("NCCOM 3") based on the bioimpedance principle was compared to a CO computer based on standard thermodilution measurements. Simultaneous measurements were made on dogs who were ventilated with or without positive end expiratory pressure (PEEP). There was no correlation of cardiac output measurements with the two methods (r = 0.10, n = 60). Comparing only measurements without PEEP yielded r = 0.41. Thermodilution measurements showed the well-known decline in cardiac output during PEEP, whereas the bioimpedance device recorded an increase in cardiac output. These differences were statistically significant. We conclude that the NCCOM 3 cannot at present replace the invasive standard methods of CO measurement in ventilated patients. A lack of differentiation of circulatory effects, thoracic gas volume, and intrathoracic fluid content is the most likely cause of the discrepancies seen. 相似文献
102.
R. E. Schmidt U. Budde C. Bröschen-Zywietz G. Schäfer C. Mueller-Eckhardt 《Annals of hematology》1984,48(1):19-25
Summary This study of the effect of high-dose intravenous gammaglobulins with one or two courses of therapy in 18 adults with idiopathic thrombocytopenia purpura showed a platelet rise in thirteen patients. The highest response rates were seen in splenectomized adults. In chronic patients the response was transient only. If therapy was effective, increased values of platelet-associated IgG were reduced, while shortened platelet survival times were prolonged. There was no influence of high-dose gammaglobulins on platelet function. Different 7S-preparations such as -propiolactone modified Ig, pH 4 treated Ig and reduced and alkylated Ig have comparable effects.Supported by the Deutsche Forschungsgemeinschaft (Mu 277/9-4) 相似文献
103.
104.
105.
Isabel M. A. Brüggenwirth Maureen J. M. Werner René Adam Wojciech G. Polak Vincent Karam Michael A. Heneghan Arianeb Mehrabi Jürgen L. Klempnauer Andreas Paul Darius F. Mirza Johann Pratschke Mauro Salizzoni Daniel Cherqui Michael Allison Olivier Soubrane Steven J. Staffa David Zurakowski Robert J. Porte Vincent E. de Meijer all the other contributing centers the European Liver Intestine Transplant Association 《Transplant international》2021,34(10):1928-1937
High-risk combinations of recipient and graft characteristics are poorly defined for liver retransplantation (reLT) in the current era. We aimed to develop a risk model for survival after reLT using data from the European Liver Transplantation Registry, followed by internal and external validation. From 2006 to 2016, 85 067 liver transplants were recorded, including 5581 reLTs (6.6%). The final model included seven predictors of graft survival: recipient age, model for end-stage liver disease score, indication for reLT, recipient hospitalization, time between primary liver transplantation and reLT, donor age, and cold ischemia time. By assigning points to each variable in proportion to their hazard ratio, a simplified risk score was created ranging 0–10. Low-risk (0–3), medium-risk (4–5), and high-risk (6–10) groups were identified with significantly different 5-year survival rates ranging 56.9% (95% CI 52.8–60.7%), 46.3% (95% CI 41.1–51.4%), and 32.1% (95% CI 23.5–41.0%), respectively (P < 0.001). External validation showed that the expected survival rates were closely aligned with the observed mortality probabilities. The Retransplantation Risk Score identifies high-risk combinations of recipient- and graft-related factors prognostic for long-term graft survival after reLT. This tool may serve as a guidance for clinical decision-making on liver acceptance for reLT. 相似文献
106.
Notfall + Rettungsmedizin - Das akute Koronarsyndrom ist der häufigste Grund für einen Rettungsdiensteinsatz in Deutschland. So resultieren in etwa 20–25 % aller Einsätze... 相似文献
107.
108.
In 54 cases of ruptured medial semilunar cartilages of the knee joint the bone mineral mass in the distal end of the femur was measured 0–5 years following removal of the injured cartilage. The bone mineral mass was significantly decreased. There was no tendency of restoration of the bone mass with time.Financial support was obtained from the Swedish Medical Research Council No: K69-23X-2737-01 and from the Gustav V 80: th Anniversary Foundation. 相似文献
109.
The relation between renal and biliary excretion of drugs was investigated in dependence on physicochemical factors, on age, and on repeated administration of hormones and xenobiotics for stimulation. Furthermore, the relation between molecular parameters of drugs and the degree of compensation of drug elimination after blockade of one excretion pathway (nephrectomy--NX, bile duct ligation--DL) was characterized. Experiments were performed on female 20-day and 55-day-old rats to demonstrate changes in the relationship between kidney and liver for drug elimination during ontogenesis. Finally it was tried to correlate the effect of a stimulation of elimination capacity of kidney and liver after repeated administration of hormones or xenobiotics and the physicochemical features of clearance substances tested. For estimation of physicochemical differences of the model substances a so called "rank coefficient" R (0-100) was used. It was calculated from molecular weight, lipophilicity, degree of ionization at pH 7.4, and protein binding rate. Compounds with low ranks (low values of molecular weight, lipophilicity, and protein binding, nearly completely ionic at pH 7.4) are eliminated first of all via urine. High ranks are typical of drugs preferentially eliminated into bile. Intermediate ranks (40-60) have been obtained for substances eliminated effectively both via kidney and liver. For these compounds only, a distinct compensation via the intact elimination route can be expected after blocking operations. Qualitative age differences could not be found. But there were differences concerning relation between acceleration of transport capacity of kidney and liver during postnatal maturation and physicochemical properties of the respective test substance.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
110.
Modulation of O6-methylguanine-DNA methyltransferase in rat and hamster liver after treatment with dimethylnitrosamine 总被引:3,自引:0,他引:3
J Hall H Brésil M Serres G Martel-Planche C P Wild R Montesano 《Cancer research》1990,50(17):5426-5430
Distinct species differences exist between BDIV rats and Syrian Golden hamsters in the repair of methylated DNA lesions, after single exposures to dimethylnitrosamine (DMN). The promutagenic lesions O6-methylguanine (O6-MeG) and O4-methylthymidine were actively repaired in rat liver; in contrast, in hamster liver the levels of O6-MeG remained relatively stable while O4-methylthymidine levels were reduced. Species differences in the levels of two enzymes involved in the repair of DNA alkylation damage were also noted. An increase in the methylpurine-DNA glycosylase levels was seen in both species following DMN exposure; however, significant species differences in the inactivation and subsequent time course of recovery of the "suicide protein" O6-MeG-DNA methyltransferase were observed. In the rat a rapid recovery of activity began within 24 h of DMN exposure (20 mg/kg) and an approximately 3-fold induction in enzyme levels was observed at 96 h. In hamster liver, in which the constitutive level of expression of this enzyme is similar, no activity was detectable up to 96 h after treatment (25 mg/kg DMN). Only in animals in the lowest treatment group (2.5 mg/kg DMN) was a significant recovery seen, 264 h after treatment. The data presented suggest that the schedule of DMN treatment, in particular the time between doses of the carcinogen and the regeneration of the O6-MeG-DNA methyltransferase, would evoke different carcinogenic responses in hamster and rat liver following chronic exposure to alkylating agents. 相似文献