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51.
The effect of prolonged hypercapnia on carotid chemoreceptor discharge frequency has not been elucidated. In addition, the effect of acute hypercapnia on chemoreceptor discharge has not been determined in the goat, a species commonly used for ventilatory control studies. Therefore, we determined the effects of acute and prolonged normoxic-hypercapnia on single fiber output of the carotid body of chloralose anesthetized goats. The animals were paralyzed and artificially ventilated. The average acute response curve for 12 single fibers was linear over the range of 30-80 Torr PaCO2 with a mean slope of 0.115 +/- 0.057 (SD) imp.sec-1.Torr-1 PaCO2. Elevated discharge frequency was maintained during prolonged (up to 240 min, n = 11) steady-state hypercapnia (X PaCO2 = 85 Torr). No systematic time-dependent changes in afferent discharge frequency occurred during the period. The findings obtained during sustained hypercapnia are in contrast to the time-dependent increase in carotid body activity seen previously in our laboratory with prolonged normocapnic-hypoxia of up to 240 min duration. 相似文献
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H S Thomsen K Rasmussen F Burcharth S L Nielsen 《Acta radiologica (Stockholm, Sweden : 1987)》1988,29(1):138-140
The perfusion of two pancreatic transplants were examined three times a week for the first five postoperative weeks by intravenous angiography using 99Tcm-pertechnetate. Worsening of the perfusion always preceded or was associated with deterioration of the pancreatic function. Accordingly, radionuclide angiography may have an important place in the systematic monitoring of pancreatic transplants in the critical postoperative period. 相似文献
55.
O. May M.D. H. Kirkegaard Nielsen M. U. Werner 《Acta anaesthesiologica Scandinavica》1988,32(3):239-243
A new and simple acceleration transducer (ACT)–based system of neuromuscular monitoring has recently been introduced. The precision of this transducer has been evaluated as compared to a conventional force displacement transducer (FDT) in the present study. Ten progressions of spontaneous recovery from atracurium–induced block with simultaneous measurements using the ACT on one hand and the FDT on the other were studied. Five individuals undergoing elective surgery in modified neurolept anaesthesia and one ICU–patient requiring prolonged neuromuscular blockade, sedated with pentobarbital, were included. Measurements were carried out on the latter patient on 5 consecutive days. Train–of–four (TOF) stimulation was used, readings were given in twitch heights (TH) (Tl/control value), and when four responses were obtained in TOF–ratios (T4/T1). Linearity was achieved after logit–transformation and the values regressed on time for each progression of recovery. Analysis of variance was applied to the regressions for the TH and TOF–ratio readings of each transducer. No significant differences were found, either between variation due to differences between slopes or variation due to technical error between the two transducers. The study indicates that the ACT is equal to the FDT with regard to precision in clinical recordings on atracuriumrelaxed individuals. 相似文献
56.
B Kappel J Nielsen K Brogaard Hansen M Mikkelsen A J Therkelsen 《British journal of obstetrics and gynaecology》1987,94(1):50-54
The clinical significance of placental perforation and blood-stained amniotic fluid was studied in a group of 7238 Danish women undergoing mid-trimester amniocentesis for prenatal diagnosis under ultrasound guidance. The risk of spontaneous abortion was significantly increased both in pregnancies where the placenta was perforated and in those with blood-stained amniotic fluid. The risk estimate nearly doubled after placental perforation and more than doubled with a bloody tap. It is concluded that for women at relatively low risk of a fetal genetic abnormality, the indication of the amniocentesis should be reconsidered if a placental perforation is unavoidable. 相似文献
57.
B. W. Nielsen T. Bjerke T. M. E. Damsgaard T. Herlin K. Thestrup-Pedersen P. O. Schiøtz 《Inflammation research》1992,35(3-4):170-178
Increased osmotic pressure has been reported to cause non-cytotoxic histamine release (HR) from human basophils, as well as a potentation of HR induced by anti-IgE. In this study, the effects of hyperosmolar Na–K-acetate (300–600 mOsm/kg H2O) on HR was studied in washed human blood cells from newborns, adult volunteers and patients with severe atopic dermatitis. These three patient groups represesented 3 very distinct populations with respect to total plasma IgE content, medians were <0.2 IU/ml, 20.5 IU/ml and 2508 IU/ml, respectively. Increasing osmolarity to 500 mOsm/kg H2O caused little HR in the absence of other stimuli, whereas at 600 mOsm/kg H2O a significant increase in spontaneous HR was seen. The HR induced by anti-IgE and Concanavalin A, acting through the IgE-receptor, was increased approximately twofold at 500 mOsM/kg H2O. Responses were highly correlated to results at 300 mOsm/kg H2O. The use of 600 mOsm/kg H2O buffers caused a further increase in most, but not all blood samples. The potentiation of IgE-receptor-mediated HR when using hyperosmolar media was clearly independent of plasma IgE contents, and did not change the concentration-response to anti-IgE. In contrast, HR induced by the IgE-receptor-independent stimuli, Formyl-met-leu-phe and calcium ionophore A 23187, were not enhanced at all by incrased osmotic pressure. We conclude, that hyperosomolar media selectively enhance IgE-receptor-mediated HR. The use of hyperosmolar media may therefore be beneficial in a diagnostic application of washed blood HR assays use in allergy diagnosis. 相似文献
58.
A prospective, consecutive study of the aetiology of treatment-associated diarrhoea was conducted in 25 patients with disseminated germ cell cancer treated with intensive chemotherapy. Clostridium difficile was isolated in 45% of the diarrhoea episodes, which makes this species the most important bacterial pathogen in the development of clinically significant diarrhoea in this group of immunocompromised patients. 相似文献
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60.
J. Viby Mogensen M.D. Ph.D. E. Jensen M. Werner H. Kirkegaard Nielsen 《Acta anaesthesiologica Scandinavica》1988,32(1):45-48
A new method for monitoring neuromuscular function based on measurement of acceleration is presented. The rationale behind the method is Newton's second law, stating that the acceleration is directly proportional to the force. For measurement of acceleration, a piezo-electric ceramic wafer was used. When this piezo electrode was fixed to the thumb, an electrical signal proportional to the acceleration was produced whenever the thumb moved in response to nerve stimulation. The electrical signal was registered and analysed in a Myograph 2000 neuromuscular transmission monitor. In 35 patients anaesthetized with halothane, train-of-four ratios measured with the accelerometer (ACT-TOF) were compared with simultaneous mechanical train-of-four ratios (FDT-TOF). Control ACT-TOF ratios were significantly higher than control FDT-TOF ratios: 116 +/- 12 and 98 +/- 4 (mean +/- s.d.), respectively. In five patients not given any relaxant during the anaesthetic procedure (20-60 min), both responses were remarkably constant. In 30 patients given vecuronium, a close linear relationship was found during recovery between ACT-TOF and FDT-TOF ratios. It is concluded that the method fulfils the basic requirements for a simple and reliable clinical monitoring tool. 相似文献