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1.
Neutrophil oxidative metabolism, C3d and beta 2 microglobulin levels, were assessed in nine consecutive patients undergoing cardiopulmonary bypass surgery with polypropylene hollow fiber oxygenators for open cardiac operations. Generation of oxygen free radicals by neutrophils was measured as luminol-enhanced chemiluminescence after stimulation with opsonized Zymosan and phorbol myristate acetate. A significant increase in light emission was detected by using both of the chemiluminescence stimulators. Moreover, a remarkable and significant increase in C3d levels was found already at 10 min. Conversely minimal changes in levels of beta 2 microglobulin were detected during cardiopulmonary bypass surgery. These data suggest that the impact of the patient blood with the foreign surface of cardiopulmonary bypass results in activation of phagocyte cells with increased potential in oxygen consumption. These effects could be partially complement-mediated.  相似文献   
2.
We investigated thein vitro effects of increasing concentrations (10–5–10–3 M) of four muscle relaxants (succinylcholine, d-tubocurarine, vecuronium and atracurium) on histamine release (HR) from human peripheral blood basophils and mast cells isolated from lung parenchyma (HLMC) and skin tissues (HSMC). Basophils released less than 5% of their histamine content when incubated with any one of the muscle relaxants. In contrast, mast cells showed a marked heterogeneity in their response. Succinylcholine did not induce HR from any type of mast cell, and only high concentrations of d-tubocurarine (10–3 M) caused HR from HSMC and HLMC. Vecuronium concentration-dependently induced HR from HLMC and HSMC. Atracurium concentration-dependently caused marked HR from HLMC and HSMC up to a maximum of 46.2±15.1% and 30.6±6.0%, respectively. From both HLMC and HSMC HR caused by atracurium and vecuronium was extremely rapid (t1/2<1 min).=" the=" releasing=" activity=" of=" atracurium=" and=" vecuronium=" on=" hlmc=" and=" hsmc=" was=" reduced,=" but=" not=" abolished,=" by=" lowering=" the=" temperature=" of=" the=" incubation=" buffer=" to=" 22°c=" and=" 4°c.=" these=" results=" confirm=" that=" there=" are=" functional=" differences=" between=" human=" basophils=" and=" mast=" cells=" and=" among=" mast=" cells=" isolated=" from=" different=" anatomical=" sites=" in=" response=" to=" the=" muscle=" relaxants=">  相似文献   
3.
A working scheme developed in our laboratory for identification (by species group and species) of coagulase-negative staphylococci (CNS) was evaluated with 201 consecutive isolates and then validated by using the reference method of Kloos and Schleifer (W. E. Kloos and K. H. Schleifer, J. Clin. Microbiol. 1:82-88, 1975). This five-test simple scheme (referred to here as the simple scheme) combines the novobiocin susceptibility test with tests for urease, pyrrolidonyl arylamidase, ornithine decarboxylase, and aerobic acid from mannose. The addition of one or two tests within a particular species group could then positively identify the isolate. Two commercial systems, Staph-Zym (Rosco) and API-Staph (bioMérieux), along with results obtained by using Rosco diagnostic tablets (nongrowth tests), were also compared with the reference method. One isolate could not be identified even by the reference method. Of the remaining 200 strains, 191 (95.5%) strains were correctly identified with Staph-Zym and 171 strains (85.5%) were correctly identified with API-Staph. The most frequent clinical CNS species isolated were Staphylococcus epidermidis (50.5%), S. haemolyticus (18.5%), S. saprophyticus subsp. saprophyticus (16.0%), S. lugdunensis (6.0%), and S. warneri (2.5%). The simple scheme validated with the reference method has demonstrated an excellent correlation in the identification of the three most frequent species isolated: S. epidermidis, S. haemolyticus, and S. saprophyticus subsp. saprophyticus. With the simple scheme, identification of CNS was possible within 24 h after the enzymatic tests were used, whereas up to 72 h is necessary for the growth tests. This methodology would be very useful in any clinical microbiology laboratory for the presumptive identification of CNS species groups and species.  相似文献   
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The increasing number of coronary operations performed on a beating heart has prompted the development of new techniques and instruments to expose the coronary arteries without major hemodynamic derangements. We describe an expandable surgical pad combined with a series of tapes that help to control rotations and positioning of the heart. The empty surgical pad is fixed at the bottom of the pericardial cavity. After injection of warm saline, the pad elevates and displaces the heart, and the tapes rotate and immobilize the heart in the desired position. Easy access to all coronary arteries with minimal effect on hemodynamics is possible.  相似文献   
6.
Zusammenfassung Die Diagnose eines flottierenden Thrombus in einem offenen Foramen ovale wird selten gestellt. Wir berichten über einen Patienten, bei dem aufgrund des dringenden Verdachtes auf eine Pulmonalembolie eine trans?sophageale Echokardiographie (TEE) durchgeführt wurde. Mit Hilfe der TEE konnte der Verdacht der Pulmonalembolie erh?rtet werden. Als überraschungsbefund fand sich jedoch im rechten und linken Vorhof ein langer, wurmf?rmiger, sehr mobiler Thrombus, der im offenen Foramen ovale eingekeilt war. Der Patient wurde aufgrund dieser Diagnose unverzüglich einem chirurgischem Eingriff unterzogen, wobei sich der TEE-Befund best?tigte und ein 19 cm langer Thrombus entfernt wurde. Mit Hilfe der TEE konnte der Riesenthrombus erkannt und einer entsprechenden Therapie zugeführt werden, wodurch Komplikationen, wie das Auftreten einer neuerlichen Pulmonalembolie oder einer paradoxen Embolie, verhindert werden konnten. Eingegangen: 10. August 1998 Akzeptiert: 12. August 1998  相似文献   
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In order to examine (i) the association between weight status and musculoskeletal complaints (MSC) in children, and (ii) whether overweight and obese children have a higher risk of developing MSC than normal‐weight children Medline, Embase, Web of Science and Cochrane were searched (all years up to 2 January 2013) for observational studies studying direct associations between body mass index (or weight status) and MSC in children. Forty studies, together studying over one million children, were included. There was moderate quality of evidence that being overweight in childhood is positively associated with musculoskeletal pain (risk ratio [RR] 1.26; 95% confidence interval [CI]: 1.09–1.45). In addition, low quality of evidence was found for a positive association between overweight and low back pain (RR 1.42; 95% CI: 1.03–1.97) and between overweight and injuries and fractures (RR 1.08; 95% CI: 1.03–1.14). Although the risk of developing an injury was significantly higher for overweight than for normal‐weight adolescents (RR: 2.41, 95% CI: 1.42 to 4.10), this evidence was of very low quality. Overweight and obesity are associated with musculoskeletal pain, injuries and fractures as early as childhood. More high‐quality prospective cohort studies are needed to study the nature of this relationship.  相似文献   
9.
BACKGROUND: The reimplantation type of valve-sparing procedure does not allow proper reconstruction of the sinuses of Valsalva. We assessed the valve motion after a reimplantation type (David I) of valve-sparing procedure using a new Dacron conduit that incorporates sinuses of Valsalva. METHODS: Nine consecutive patients undergoing an aortic valve-sparing procedure using the new conduit were studied using two-dimensional transesophageal echocardiography shortly (2 +/- 1 months) after operation to determine root distensibility, expressed as percent change in radius and as pressure strain of the elastic modulus. Next, monodimensional view was used to assess valve motion in its various phases (rapid valve opening velocity, slow closing leaflet displacement, rapid valve closing velocity, maximal leaflet displacement, and leaflet displacement before valve closure). Seven healthy individuals served as control subjects. RESULTS: Root distensibility was reduced at the level of the annulus and sinotubular junction but was similar to control subjects at the level of the sinuses (percent change in radius, 4.1% +/- 0.8% versus 4.5% +/- 1.2%; pressure strain of the elastic modulus, 1,286 +/- 674 g/cm2 versus 1,195 +/- 628 g/cm2). Rapid valve opening (69 +/- 34.4 cm/s versus 51 +/- 11.9 cm/s) and closing (47.6 +/- 16 cm/s versus 36.4 +/- 9 cm/s) velocity as well as slow closing leaflet displacement (24% +/- 4.7% versus 22.1% +/- 7.9%), maximal leaflet displacement (20.1 +/- 4 mm versus 22.7 +/- 1.9 mm), and leaflet displacement before valve closure (15.2 +/- 3 mm versus 17.6 +/- 0.8 mm) were similar to control subjects. CONCLUSIONS: The new aortic root conduit used in a reimplantation type of valve-sparing procedure allows the anatomic reconstruction of the aortic root with leaflet motion similar to that of normal subjects.  相似文献   
10.
BACKGROUND: Controversies still exist over the optimal temperature for blood cardioplegia and systemic perfusion. This study investigates the effect of temperature of blood cardioplegia and systemic perfusion on the release of troponin I and other biochemical markers. METHODS: One hundred and fifty-four consecutive patients were randomly assigned to one of two cardioplegic and systemic perfusion strategies of cold blood cardioplegia with moderate systemic hypothermia (27 degrees C) or tepid blood cardioplegia with mild systemic hypothermia (33 degrees C). Cardiac troponin I and other biochemical markers were measured at baseline, at the end of surgery, at 12 hours and daily thereafter. A two-way ANCOVA for repeated measure was performed to test the effect of cardioplegia on enzyme release independently of variables that were different between the two groups. RESULTS: The time course of dismission of troponin I, creatine kinase MB, and lactate dehydrogenase were significantly lower with tepid blood cardioplegia and mild systemic perfusion independently of the number of distal anastomoses, CPB time, cross clamp time or total volume of cardioplegia. There were no differences between the two groups in the release of total creatine kinase, aspartate transaminase and alanine transferase. CONCLUSIONS: Both strategies of myocardial protection and systemic perfusion guarantee subclinical minor myocardial damage. The strategy of tepid whole blood cardioplegia and mild systemic hypothermia seems to preserve myocardium better than whole blood cold cardioplegia.  相似文献   
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