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991.
992.
S. Maier A. Kleinsasser C. Keller G. Kühbacher A. Löckinger 《Paediatric anaesthesia》2002,12(9):826-826
Introduction QT interval prolongation may cause the potentially lethal tachyarrhythmia torsades de pointes ( 1 ). The cause of the QT interval prolongation may be a congenital mutation in genes encoding cardiac potassium and sodium channels ( 2 ) or be acquired following drug administration ( 3 ) or metabolic disorders ( 4 ). Among a few other drugs volatile anaesthetics prolong the QT interval. During the last few years sevoflurane has become the most used volatile anaesthetic for the induction of anaesthesia in infants.
Methods This investigation, on infants aged from 1 to 6 months, was approved by the institutional ethic committee. Thirty-six otherwise healthy infants due to elective surgery were included in our study The patients were randomly assigned to one of two treatment groups. Group S ( n = 24) was anaesthetised with sevoflurane, Group H was anaesthetised with halothane. ECG recordings were taken before the anaesthesia onset, 15 min after the first contact with the volatile anaesthetic and 60 min after the ending of the volatile gas exposition. QTc interval was calculated using the Bazett's formula ( 5 ).
Results QTc interval was significantly ( P < 0.0002) (Table 1) lengthened 15 min after anaesthesia induction with sevoflurane as well as 60 min ( P < 0.01) after the ending of the gas exposition without any difference in age and gender. The QTc interval in patients anaesthetised with halothane did not show any significant change.
Methods This investigation, on infants aged from 1 to 6 months, was approved by the institutional ethic committee. Thirty-six otherwise healthy infants due to elective surgery were included in our study The patients were randomly assigned to one of two treatment groups. Group S ( n = 24) was anaesthetised with sevoflurane, Group H was anaesthetised with halothane. ECG recordings were taken before the anaesthesia onset, 15 min after the first contact with the volatile anaesthetic and 60 min after the ending of the volatile gas exposition. QTc interval was calculated using the Bazett's formula ( 5 ).
Results QTc interval was significantly ( P < 0.0002) (Table 1) lengthened 15 min after anaesthesia induction with sevoflurane as well as 60 min ( P < 0.01) after the ending of the gas exposition without any difference in age and gender. The QTc interval in patients anaesthetised with halothane did not show any significant change.
Table 1 相似文献
993.
Effect of nedocromil on bronchospasm induced by inhalation of substance P in asthmatic subjects 总被引:3,自引:0,他引:3
N Crimi F Palermo R Oliveri B Palermo C Vancheri R Polosa A Mistretta 《Clinical allergy》1988,18(4):375-382
Several studies have demonstrated that neuropeptides are present in peptidergic fibres of bronchial tissue. The aim of the present study was to evaluate in vivo the effect of nedocromil sodium (2 x 2 mg) on bronchospasm induced by inhalation of substance P. Six moderate asthmatic patients, mean age 25.17 years, were studied. Airway response was measured as FEV1 and the dose of substance P (using a dose range of 23-736 nmol) producing a 20% decrease in FEV1 (PD20) was calculated from the individual semilogarithmic dose-response curves. Patients were studied on 3 separate days in a randomized, double-blind manner. On the first day a baseline PD20 value was determined. On subsequent days substance P challenge was performed after pretreatment (20 min before challenge) with either placebo or nedocromil sodium. Student's paired t-test and Wilcoxon's test were used for statistical analysis. The results of this study demonstrated that inhalation of substance P causes a dose-dependent bronchoconstriction and that the bronchoconstriction induced by substance P can be prevented by pre-treatment with nedocromil sodium. 相似文献
994.
This study examined the immunoregulatory role of recombinant interleukin 4 (IL-4), also known as B-cell stimulating factor 1, on the generation of cytotoxic effector cells from normal and leukaemic human blood mononuclear cells. When tested on cells from normal individuals, the addition of IL-4 to mixed lymphocyte cultures led to a dose-dependent proliferation of T-helper cells (CD3, 4 positive) with a concomitant decrease in phenotypic and functional cytotoxic T cells and natural killer (NK) cells. IL-4 also inhibited the interleukin-2 (IL-2)-induced generation of lymphokine-activated killer (LAK) activity when added at the beginning of mixed lymphocyte culture. When tested on mature leukaemic NK cells, IL-4 also inhibited the ability of IL-2 to induce LAK function using a short-term culture system. These results show that IL-4 acts on both normal and leukaemic cells and suggests that it acts at more than one level during the development of LAK function. 相似文献
995.
B. J. d'Othe S. Haulon C. Mounier-Vehier J. P. Beregi O. Jabourek S. Willoteaux 《European journal of vascular and endovascular surgery》2002,24(6):516-523
OBJECTIVE: evaluation and comparison of the endovascular treatment of isolated aortic and aortoiliac atherosclerotic lesions (stenoses and occlusions). METHODS: a percutaneous endovascular procedure was performed in 52 patients (38 men and 14 women) with a mean age of 52 years (range, 25-85 years). The baseline angiogram showed 35 aortic lesions (31 stenoses, 4 occlusions) and 17 aortoiliac lesions (14 stenoses, 3 occlusions). Percutaneous techniques used in this series included variable combinations of transluminal angioplasty and stenting. All stents placements were performed over-the-wire using the transfemoral route (most often bilateral approach). Clinical examination and Duplex-scan were performed at discharge, 1 month, 6 months, 12 months, and then yearly. RESULTS: technical success was 100% for aortic and aortoiliac lesions. Angiographic success rates were comparable for aortic (91%) and aortoiliac (94%) lesions. No death occurred during or early after the endovascular intervention. Duplex-scan confirmed 100% patency rate at discharge. There was no significant difference between the aortic (94%) and aortoiliac (96%) groups regarding immediate clinical improvement. Mean follow-up was 34+/-31 months (range, 0-130 months). The cumulative primary patency rate at 36 months was 85% in the aortic group and 86% in the aortoiliac group. Clinical success, defined as a symptom-free status at the end of follow-up, was also similar in both groups. CONCLUSION: endovascular treatment of isolated aortic lesions of the infra-renal aorta has favorable outcomes comparable to those of aortoiliac lesions. 相似文献
996.
Edwin B. Fisher Jr. 《Addictive behaviors》1997,22(6):680
The commodity model of social support and features of Nondirective Support may clarify varied results of support interventions for smoking cessation. A commodity model views social support as attractive in and of itself and as an alternative to high-risk choices such as smoking. If such support is easily accessible, a would-be quitter is less likely to choose to smoke. Consistent with the commodity model, social support interventions tend to be effective as long as support remains available, but they lose their effects when support is terminated. From a second approach, Nondirective Support entails accepting recipients' goals, cooperating without taking control, and validating recipients' feelings. In contrast, Directive Support entails taking control and telling recipients what to do and feel. Review of support interventions indicates the value of the continued availability of support suggested by the commodity model and of Nondirective Support's flexibility and responsiveness to the person. 相似文献
997.
998.
999.
B. A. Stoll 《Annals of oncology》1997,8(3):223-225
Background: The study reviews the anticancer properties of naturalisoflavones which occur in especially high concentration in soybeans. Itconsiders the suitability of soybean products for clinical trials aiming toreduce the progression of breast cancer.Methods: Evidence is reviewed that plant isoflavones such asgenistein show cytostatic activity against human mammary cancer cell linesin vitro and can also suppress carcinogen-induced mammary cancer inyoung and mature rats.Results: Plant isoflavones are converted in the bowel to compoundswith potential antioestrogenic and antioxidative properties. These compoundsshow cytostatic activity for both oestrogen receptor-positive and negativehuman mammary cancer cell lines, and also inhibit growth and progress of therat mammary cancer model. The high content of soybean products in the diet ofAsian women has been postulated as one reason for their relatively low breastcancer incidence.Conclusion: Preclinical studies suggest that soybean products begiven priority for clinical trials in breast cancer protection. A pilot studycould test soy protein supplements as long-term adjuvant dietary treatmentafter primary surgery for early breast cancer, looking for a decrease in therisk of recurrence or of second primary tumours. 相似文献
1000.
Tayama K; Takamori S; Mitsuoka M; Hiraki H; Ohtsuka S; Hayashi A; Aoyama Y; Shirouzu K 《Japanese journal of clinical oncology》1997,27(6):401-405
The aim of this study was to investigate retrospectively the efficacy of
expandable metallic stents (EMSs) for severe respiratory distress in
patients with central airway obstruction. Twenty patients with central
airway obstructions were treated with an EMS. An intraluminal stricture was
present in 15 and an extraluminal stricture in 5 patients. Of the 15
patients with intraluminal stenosis, 11 exhibited symptomatic improvement.
All 11 patients had tumor infiltration occupying less than 50% of the
endoluminal diameter. The other four patients with intraluminal stenosis
had tumor infiltration occupying > 50% of the endoluminal diameter and
demonstrated no improvement. All five patients with extraluminal stenosis
were improved. EMS is useful for an extraluminal stricture in the central
airway and the effect of EMS for intraluminal stenosis is related to the
degree of infiltration and of tumor progression itself.
相似文献