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11.
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A. Tytko B. Exner E. Schrock M. Barthel E. G. Siegel H. Köhler K. Nebendahl U. Leonhardt 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》1993,378(2):82-85
The effect of hydroxyethyl starch on pancreas preservation with cardioplegic histidine-tryptophan-ketoglutarate solution (HTK) was investigated. The study was performed using an in vitro reperfusion system of the porcine pancreas. During organ preservation pancreatic weight, arterial pressure, volume flow, and washout of amylase and lactate were quantified. Addition of hydroxyethyl starch did not affect arteriovenous volume flow or washout of amylase and lactate during protective perfusion after pancreas preparation. However, hydroxyethyl starch in HTK prevented an increase in pancreatic weight at the end of the protective perfusion (102.2 ± 4.55% vs 127.8 ± 4.62% in controls; p < 0.005) and after 24 h cold ischemia (72.9 ± 3.91 % vs. 83.5 ± 3.49 % in controls; p < 0.05). Hydroxyethyl starch did not affect postischemic organ quality assessed during reperfusion in a perfusion chamber by pancreatic vascular resistance, amylase and lactate release, insulin secretion, and oxygen consumption. We conclude that hydroxyethyl starch does not bring about any further improvement in immediate postischemic organ quality assessed in an in vitro reperfusion system.
Hydroxyäthylstärke bringt keine verbesserung der pankreaskonservierung mit HTK-Lösung
Zusammenfassung Der Effekt von Hydroxyäthylstärke auf die Pankreaskonservierung mit der kardioplegischen Histidin-Tryptophan-Ketoglutarat-Lösung (HTK) wurde untersucht. Die Studie wurde an einem Reperfusionssystem des in vitro perfundierten Pankreas vom Schwein durchgeführt. Während der Organprotektion wurden das Pankreasgewicht, der arterielle Perfusionsdruck, die Volumenstromstärke sowie Amylase und Laktat im Perfusat bestimmt. Der Zusatz von Hydroxyäthylstärke bewirkte keine Änderung der Volumenstromstärke oder der Amylase- und Laktatauswaschung aus dem Organ während der Protektion. Allerdings konnte eine Zunahme des Organgewichts am Ende der protektiven Perfusion (102,2 ± 4,55% vs. 127,8 ± 4,62%in Kontrollen; p < 0,005) und nach 24 h kalter Ischamie (72,9 ± 3,91 vs. 83,5 ± 3,49% in Kontrollen; p < 0,05) durch Hydroxyathylstärke in der HTK-Lösung verhindert werden. Hydroxyäthylstärke hatte keinen Einfluß auf die postischämische Organqualität, die während der Reperfusion in einer Perfusionskammer anhand von Gefäßwiderstand, Amylase- und Laktatfreisetzung, Insulinsekretion und Sauerstoffverbrauch abgeschätzt wurde. Wir schließen daraus, daß Hydroxyäthylstärke die sofort nach einer Ischämie in einem In-vitro-Reperfusionssystem bestimmte Pankreasfunktion nicht weiter verbessert.相似文献
13.
BACKGROUND: In view of the inconclusive reports in the literature about the response to neuroleptics of chronic schizophrenics with negative symptoms, the authors further evaluated this issue. METHOD: A sample of 30 ambulatory chronic schizophrenics meeting DSM-III-R criteria who had to a marked degree at least two negative symptoms of the five on the Scale for the Assessment of Negative Symptoms (SANS) received various therapeutic dosages of thiothixene for 3 months. The average dose was 26.75 mg/day. Subjects were periodically evaluated with the Brief Psychiatric Rating Scale, Negative Symptoms Rating Scale (a modified version of the SANS), and the Randt Memory Test. The time effect on treatment was calculated by repeated measures of analysis of variance. The relationship between the positive and negative symptoms was tested by an analysis of covariance. RESULTS: Both negative and positive symptoms improved with treatment. The negative symptoms tended to respond to treatment predominantly independently of the positive ones. At the end of the study, 63% (N = 19) of patients had improved moderately, 16% (N = 5) had improved slightly, and 20% (N = 6) had not improved. CONCLUSION: The data require further support from a long-term follow-up study that may show the extent to which these gains are maintained over time. 相似文献
14.
Jason T. Siegel M.A. Eusebio M. Alvaro PhD. M.P.H. Michael Burgoon PhD. 《The Journal of adolescent health》2003,33(6):458-461
This research is supported in part by Arizona Disease Control and Research Commission (ADCRC), Grant #9904 (M. Burgoon, PI). This study assesses how adolescent nonsmokers, at-risk smokers, and smokers differ in perceptions of smoking harms, benefits, and safety. While small differences exist when comparing attitudes and knowledge concerning short- and long-term benefits of smoking, large differences arise when attitudes and knowledge concerning the short-term benefits and the safety of casual smoking are compared. 相似文献
15.
The effects of central infusion of naloxone into the midbrain periaqueductal gray (PAG) upon predatory attack behavior in the cat were studied in 12 cats. Initially, quiet biting attack was elicited by electrical stimulation of sites within the lateral hypothalamus using monopolar electrodes. Then cannula-electrodes were implanted into sites within the PAG from which electrical stimulation facilitated or suppressed the attack response. Following identification of modulatory sites within the PAG, naloxone (1.0 micrograms/0.5 microliter) was microinjected into those sites and the effects upon hypothalamically elicited attack were assessed. At nine of twelve sites in the PAG where suppression was obtained, administration of naloxone served to block those effects. Similarly, at six of eight facilitatory sites within the PAG, naloxone also blocked the modulatory effects of PAG stimulation. However, vehicle (isotonic saline) alone did not alter the modulatory effects of PAG stimulation. Administration of DAME (250 ng/0.3 microliter) into PAG modulatory sites in four cats, two which facilitated and two that suppressed the attack response, reversed the effects of naloxone at these sites. These results demonstrate that opioid peptides within the PAG play a complex role in the expression of predatory attack behavior in the cat. 相似文献
16.
17.
W J McGahren G O Morton M M Siegel D B Borders J C James G A Ellestad 《The Journal of antibiotics》1986,39(11):1541-1550
The behavior of the free acid and ammonium salt of maduramicin towards heat and alcohols is examined. In refluxing lower alcohols the free acid material is decarboxylated. In addition a bisketal decarboxylated compound as well as an A-ring monoketal decarboxylated derivative are formed. Heating the ammonium salt of the ionophores in suspension in water, or dissolved in inert solvents such as heptane or xylene can cause decarboxylation as well as concomitant dehydration of the F-ring. Reaction of dansyl chloride with the free acid of maduramicin can cause dehydration of the B-ring under very mild conditions. 相似文献
18.
We predicted that children's conceptions of various self-care behaviors and social relations would be related to their degree of experience with insulin dependent diabetes mellitus (IDDM). A total of 55 children were recruited for this study in three experience groups: children with IDDM (high experience), children having a sibling with IDDM (low experience), and normal healthy children (no experience). In line with our model, children with IDDM had a more developed and sophisticated understanding of concepts associated with disease management than did either siblings of children with diabetes or the comparison group; surprisingly, experience with the disease (children with IDDM) was associated with more complex conceptions of social relations as well. 相似文献
19.
There are several urologic disorders which also involve the eye and orbit. We have compiled examples of these and reviewed the literature. Metastasis from genitourinary malignancy (including neuroblastoma), Wilms tumor, Reiter syndrome, tuberous sclerosis, von Hippel-Lindau disease, and oxalosis may all have ophthalmologic manifestations. Urologists need to be aware of these and obtain appropriate consultation in order to fully care for patients with these diseases. 相似文献
20.
CT of fatty thoracic masses. 总被引:2,自引:0,他引:2