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11.
OBJECTIVES: Persisting air leakage after pulmonary resection remains a significant problem. The aim of the study was to evaluate the incidence of air leakage after standard lobectomy and test the efficacy and safety of TachoComb (TC). METHODS: A total of 189 patients undergoing lobectomy were enrolled in a multi-centre, open, randomised, and prospective study to test the efficacy and safety of TachoComb (TC) for air leakage treatment. Air leakage was assessed by water submersion test, and scored as grades 0 if no, 1 if countable, 2 if a stream of and 3 if coalescent bubbles have been observed. Any sites with grade 3 air leakage received further stapling or limited suturing until grade 0, 1 or 2 was obtained. Treatment of air leakage was done with TC or suturing according to randomisation. Air leakage was assessed by further submersion tests. Postoperative air leakage was assessed using the Pleur-Evac system. RESULTS: Overall incidence of air leakage 48+/-6 h after surgery was 34% for TC and 37% for standard treatment (P=0.76). The reduction of intra-operative air leak intensity in the subgroup with grades 1-2 was significantly higher for the TC group (P=0.015). Postoperative air leakage intensity in the subgroup with air leakage grades 1-2 was lower for TC than standard treatment (P=0.047). The mean duration of postoperative air leakage in the subgroup with grades 1-2 was shorter for the TC group than for standard treatment, i.e. 1.9+/-1.4 vs. 2.7+/-2.2 days (P=0.015). CONCLUSIONS: TC could be proven as well-tolerated and safe. In the subgroup of patients with established air leakage, TC showed superior potential in reduction of intra-operative air leakage as well as in reduction of intensity and duration of postoperative air leakage.  相似文献   
12.
Mechanisms of Cardioprotection by Volatile Anesthetics   总被引:2,自引:0,他引:2  
  相似文献   
13.
Background: Adenosine triphosphate-regulated potassium channels mediate protection against myocardial infarction produced by volatile anesthetics and opioids. We tested the hypothesis that morphine enhances the protective effect of isoflurane by activating mitochondrial adenosine triphosphate-regulated potassium channels and opioid receptors.

Methods: Barbiturate-anesthetized rats (n = 131) were instrumented for measurement of hemodynamics and subjected to a 30 min coronary artery occlusion followed by 2 h of reperfusion. Myocardial infarct size was determined using triphenyltetrazolium staining. Rats were randomly assigned to receive 0.9% saline, isoflurane (0.5 and 1.0 minimum alveolar concentration [MAC]), morphine (0.1 and 0.3 mg/kg), or morphine (0.3 mg/kg) plus isoflurane (1.0 MAC). Isoflurane was administered for 30 min and discontinued 15 min before coronary occlusion. In eight additional groups of experiments, rats received 5-hydroxydecanoic acid (5-HD; 10 mg/kg) or naloxone (6 mg/kg) in the presence or absence of isoflurane, morphine, and morphine plus isoflurane.

Results: Isoflurane (1.0 MAC) and morphine (0.3 mg/kg) reduced infarct size (41 +/- 3%; n = 13 and 38 +/- 2% of the area at risk; n = 10, respectively) as compared to control experiments (59 +/- 2%; n = 10). Morphine plus isoflurane further decreased infarct size to 26 +/- 3% (n = 11). 5-HD and naloxone alone did not affect infarct size, but abolished cardioprotection produced by isoflurane, morphine, and morphine plus isoflurane.  相似文献   

14.
Starting with four reaction equations which are at least necessary to describe the copolymerization of two monomers, equations for the kinetics and the molecular weight regulation with and without hydrogen are derived. The equations are used to evaluate the results of the copolymerization of ethylene and 1-butene. The numerical values of the reactivity ratios r differ by approximately 3 orders of magnitude, but do not depend on whether the molecular weight is regulated by hydrogen or not. The rate of polymerization is scarcely influenced even by great amounts of 1-butene. It depends nearly completely on the concentration of ethylene. On the other hand the comonomer enormously influences the average molecular weight of the copolymer. This influence increases with hydrogen content.  相似文献   
15.
Summary The total body clearance and fractional extraction of isoprenaline (ISO) have been determined, and the relation between these parameters and cardiac output established. Whether desipramine, an inhibitor of neuronal uptake, altered the plasma catecholamine response to ISO was also investigated.Seven healthy subjects were given i.v., infusions of ISO in two, consecutive 25-min periods, at constant dose rates of 31–43 and 80–124 pmol·kg–1·min–1, respectively. The total-body (ER), pulmonary (ERp) and forearm (ERf) fractional extractions and the total body clearance (CL) of ISO were obtained from measurements of cardiac output and the steady-state ISO concentration in mixed central venous, arterial and forearm venous plasma.ISO-induced increases in cardiac output resulted in increases in CL, decreases in ER and no consistent change in ERf. ERp did not differ from zero. ISO also produced a dose-dependent increase in the mixed venous plasma concentrations of noradrenaline and 3,4-dihydroxyphenylglycol (DOPEG), and a decrease in that of adrenaline. Pretreatment with desipramine did not alter any of the pharmacokinetic parameters of ISO. Desipramine, however, reduced the mixed venous baseline plasma levels of noradrenaline (47%) and DOPEG (40%), and tended to reduce that of adrenaline (34%). It enhanced the plasma noradrenaline response 2.4-fold, abolished the plasma DOPEG response and did not alter the plasma adrenaline response to ISO.Hence, owing to its haemodynamic effects, ISO modifies its own pharmacokinetics which involve non-neuronal removal processes only. The increased DOPEG in plasma resulting from the ISO-induced increase in noradrenaline release was presynaptic in origin. Desipramine appears to reduce sympathetic activity. The enhancement by desipramine of the ISO-induced increase in plasma noradrenaline points towards recapture by neuronal uptake of at least 58% of the noradrenaline released in response to ISO.  相似文献   
16.
INTRODUCTION Under physiological conditions, interferon-α (IFN-α) is a key cytokine produced by virtually all cells in the mammalian organism in response to a variety of bacterial and viral stimuli. In response to viral infection, IFN-α produced by the infected target cells induces a number of cellular genes involved in inhibition of viral replication. In addition, IFN-α is secreted by stimulated NK-cells and T-cells and exerts a multitude of immune stimulatory effects of innate a…  相似文献   
17.
OBJECTIVE: The American Diabetes Association (ADA) recommends screening children at risk for type 2 diabetes with a fasting plasma glucose test or an oral glucose tolerance test. The purpose of this study was to describe attitudes, barriers, and practices related to type 2 diabetes screening in children among pediatric clinicians. METHODS: Pediatricians, nurse practitioners and physician assistants from a multispecialty, group practice in Eastern Massachusetts completed a mailed survey. To assess screening practice, three vignettes were presented representing pediatric patients with low, moderately high, and high risk for type 2 diabetes. The moderately high-risk and high-risk patients met ADA criteria for screening. ADA-consistent practice was defined as only screening the moderately high-risk and high-risk patients; lower-threshold practice was defined as also screening the low-risk patient; and higher threshold practice was screening only the high-risk patient. RESULTS: Sixty-two of 90 clinicians responded (69%). Based on intent to screen in the 3 vignettes, 21% of respondents reported ADA-consistent screening practice, 39% lower-threshold, and 35% higher-threshold screening practice. Five percent had incomplete or nonclassifiable responses. Many clinicians ordered screening tests other than those recommended by the ADA; few (< or =8% in any vignette) ordered only an ADA-recommended test. Preferences for nonfasting tests were influenced by nonmedical factors such as access to or cost of transportation. Inadequate patient education materials and unclear recommendations for appropriate screening methods were the most frequently reported moderate/strong barriers to screening. CONCLUSIONS: Most respondents reported type 2 diabetes screening practices that differed from current ADA recommendations. Our findings suggest that type 2 diabetes screening tests must be practical for clinicians and patients if they are to be used in pediatric practice. Further study of the benefits and cost-effectiveness of type 2 diabetes screening in children is warranted to clarify the role and optimal methods for screening in pediatric primary care.  相似文献   
18.
Zusammenfassung Bei einer 71j?hrigen Frau trat nach R?ntgenweichstrahltherapie an der Nase (Gesamtdosis 28 Gy, Gewebehalbwerttiefe 10,5–11,5 mm) eine ausgepr?gte Strahlenerosion auf. Diese zeigte 5 Wochen nach Ende der Bestrahlung noch keine Tendenz zur Abheilung. Ursache dieses ungew?hnlichen Verlaufes war ein gleichzeitig bestehender Pemphigus vulgaris. Dieser hatte sich nach der Strahlentherapie, vermutlich als Folge einer Freisetzung epidermaler Antigene, verschlimmert. Da? der Pemphigus in diesem Fall durch die Bestrahlung ausgel?st wurde – wie mehrfach in der Literatur berichtet – ist unwahrscheinlich, aber nicht sicher auszuschlie?en. Eingegangen am 11. April 1994 Angenommen am 10. Juni 1994  相似文献   
19.
Urogenital infections are established as hazards to male fertility. Various pathophysiological hypotheses have evolved from experimental and clinical studies, facilitating explanation of the effects of bacteria and immunological events on reproductive tissues. Numerous current studies have identified and evaluated infectious mediators accounting for specific molecular events in urogenital infections. Valuable studies can be expected to appear in the future due to improvements in diagnostic procedures and new classifications of urogenital infections.  相似文献   
20.
The growth of a panel of eight different human glioblastoma cell lines was examined in a human tumor cloning assay in agar, a tritiated thymidine uptake assay, and by counting cell numbers, in cultures performed in the absence or presence of increasing concentrations (1 to 100 ng/ml) of recombinant human stem cell factor (SCF). Growth of 7 of 8 cell lines was not significantly and reproducibly affected by recombinant human SCF. However, growth of the CRL 1620 cell line could be stimulated up to 5-fold by the cytokine. In contrast to the other cell lines investigated, CRL 1620 expressed the c-kit protooncogene assessed on the mRNA and protein level. Furthermore, SCF-induced proliferation of CRL 1620 cells was sensitive to the tyrosine kinase inhibitor erbstatin. Our data suggest that SCF can be operative in growth modulation of malignant cells outside the hematopoietic system, and this finding should be further studied for its possible clinical implications.  相似文献   
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