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21.
Mediastinitis is a devastating complication following median sternotomy. Continuous povidone-iodine (PVP-I) irrigation has been advocated as therapy because of its broad antimicrobial spectrum and its apparent safety. However, several recent clinical reports have warned of suspected local and systemic iodine toxicity. The purpose of this study is to determine if significant amounts of iodine can be absorbed systemically via the mediastinum, and if so, what toxicity (local and/or systemic) may result. PVP-I (0.5%) was continuously irrigated into the pericardial sacs of three dogs via catheters for 48 hr. Serial serum and urine iodine levels were determined. The serum steady-state concentration (Css), the rate elimination constant (k), the urinary clearance (Cl), and the serum half-life (t 1/2) for iodine were assessed. Serum electrolytes, Bun, Cr, and arterial pH were measured to assess systemic iodine toxicity. Tissue samples of the heart, pericardium, liver, and kidney were examined histologically for evidence of local or end-organ iodine toxicity. This study demonstrated that the absorption of iodine during continuous mediastinal irrigation with PVP-I follows zero-order pharmacokinetics, just as if it were being given by continuous intravenous infusion. The baseline serum iodine concentration was 145.9 +/- 64.3 micrograms/dl, Css was 29,290 +/- 101.4 micrograms/dl, k was 0.0996 +/- 0.009/hr, Cl was 872.4 +/- 119.3 ml/hr, and t1/2 was 6.22 hr. Urinary excretion of iodine increased in proportion to the serum iodine. Measured serum chloride increased in a linear manner (r = 0.949), while serum Na, K, Bun, Cr, and pH were unchanged.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
22.
Zusammenfassung In der Zeit vom 01. Juli 1990 bis zum 30. Juni 1994 wurden 65 113 Untersuchungen au?erhalb der Regeldienstzeit durchgeführt. Die vorliegende Analyse schlüsselt die Leistungen auf nach Alter und Geschlecht im Vergleich zum Gesamtkollektiv dieser Vierjahresperiode, nach dem Zeitpunkt der Untersuchung, nach den untersuchten Organen und nach der eingesetzten Technik. Ca. 1/3 der Leistungen fallen in den Zeitraum zwischen 16.00 und 20.00 Uhr und k?nnten durch einen versetzten Tagdienst aufgefangen werden. Ein weiteres Drittel entf?llt auf den Zeitraum zwischen 20.00 und 8.00 Uhr am Folgetag. Der Rest entf?llt auf Feiertage und Wochenenden. Die h?ufigste Anforderung betrifft Thoraxaufnahmen auf den Intensivstationen. Etwa die H?lfte dieser Untersuchungen werden au?erhalb der Dienstzeit angefertigt; 17,2 % der Untersuchungen im Nacht- und Bereitschaftsdienst betreffen Computer- und Magnetresonanztomographie. Das am 01. 01. 93 in Kraft getretene Gesundheitsstrukturgesetz führte zu keinen nennenswerten Verschiebungen hinsichtlich Art, Umfang und H?ufigkeit der Untersuchungen im Nacht- und Bereitschaftsdienst. Eingegangen am 17. Juni 1996 Nach überarbeitung angenommen am 24. Juli 1996  相似文献   
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The stimulus effects of ibogaine were compared with those of yohimbine, an alpha 2-adrenoceptor antagonist, 2,5-dimethoxy-4-methylamphetamine (DOM), a 5-hydroxytryptamine2 (5-HT2) agonist, and lysergic acid diethylamide (LSD), a nonspecific 5-HT agonist. Rats were trained with either yohimbine (6 mg/kg), DOM (0.6 mg/kg), or LSD (0.1 mg/kg) vs. no treatment in a two-lever discrimination task. Tests of generalization were then conducted with ibogaine. In yohimbine-trained animals, 39.7% of responses following ibogaine (15 mg/kg) were on the drug-appropriate lever, but this response level was not significantly different from no treatment-appropriate responding. A response distribution that was significantly different from responding under both drug and no treatment training conditions was observed in DOM-trained rats after administration of 15 mg/kg ibogaine. Pizotyline (BC-105) blocked all DOM-appropriate responding produced by ibogaine. In LSD-trained animals, 20 mg/kg ibogaine mimicked LSD. Pizotyline blocked LSD-appropriate responding produced by ibogaine in five of six animals. The present data suggest the involvement of 5-HT2 receptor activity, and the possibility of a 5-HT1A contribution, in the stimulus properties of ibogaine.  相似文献   
25.
Immunosuppressed recipients of organ transplants have a higher incidence of carcinoma than the general population. A retrospective analysis was made at the Department of Urology of Bonn University, investigating 236 renal allograft recipients as to the incidence of neoplasms before and after transplantation. Eleven patients developed malignant tumours after transplantation. In 4 out of these 11 patients, case history showed pre-existing malignancies. Two of the 4 patients developed a second tumour, while the other two had tumour progression (latency period 21–77 months). Three of the 4 patients died of their tumours 21, 42 and 77 months after transplantation, whereas one female patient is still alive and free of neoplasms 32 months after transplantation. In 7 out of these 11 patientsde novo tumours were diagnosed (latency period 3–88 months). All of them are still alive (NED between 15 and 85 months), six of them with good transplant function. There was no difference to be seen in the incidence of malignancies between kidneys supplied by Eurotransplant (n=40) and ABO compatible kidneys from our own donors (n=196). The higher incidence rate of neoplasms in transplant recipients requires high standards in preventive measures. Any suspicious change that may occur in the course of a thorough follow-up of transplant recipients must be removed and examined histologically. Patients with previous malignant diseases must be payed special attention, since they frequently tend to develop another malignant tumour and progression of existing tumours, respectively. As far as immunosuppression is concerned, therapeutic guidelines for the treatment of transplant recipients do not differ from those set up for patients on haemodialysis. Since immunosuppression with increased rates of tumour incidence can also be observed in dialysis patients, the mere fact of increased incidence of neoplasms cannot be taken as an argument against transplantation. With a more or less equal risk of tumour incidence the crucial factor should be the higher quality of life for transplant recipients.  相似文献   
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To investigate the influence of glucocorticosteroid therapy on the neonatal blood count, the haematologic data of 68 preterm and term infants, who had received a single dose of 1 mg dexamethasone i.v., were reviewed. White blood cell (WBC) count and platelet count increased after steroid therapy. The increase in WBCs was associated with an increase in the number of neutrophilic granulocytes, whereas the number of eosinophils decreased. We conclude that glucocorticosteroids after the neonatal blood count and influence its value as a diagnostic marker for bacterial infections.  相似文献   
28.
In order to describe the registrar population and to highlight their problems, a study using an anonymous questionnaire was conducted in August 1988 at the University of Cape Town Group of Teaching Hospitals. The average age of respondents was 32 years and the majority had family responsibilities (60% married, 41% with dependents). They had significant medical experience and postgraduate qualifications. Registrars work long hours (mean 66 +/- 13.7 h/wk), with duty shifts that can extend for up to 34 hours. Most of their time at work was devoted to patient care, with time for study and research virtually non-existent. Although the majority (61%) felt that the 'registrar experience' was worthwhile, a significant proportion of respondents (45%) had considered leaving the rotation. The study revealed several shortcomings that need to be addressed if candidates of good calibre are to be attracted, academic standards are to be maintained and sufficient specialists produced to serve the needs of our population adequately.  相似文献   
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30.
The London Dysmorphology Database.   总被引:1,自引:0,他引:1       下载免费PDF全文
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