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91.
Video-assisted minimally invasive cardiac surgery (VAMICS) is currently performed with various indications. However, despite the increasing evidence of its effectiveness, new approaches have to be defined to simplify this procedure, minimize its potential complications and limit its costs, for a wider use in the surgical community. The limited access to the aorta is a key point in VAMICS and mandates specific clamping modalities with their own limitations, costs and drawbacks. The Portaclamp (Cardio Life Research SA, Louvain la Neuve, Belgium), a new autoguided extravascular aortic cross-clamping system, has been recently proposed to facilitate VAMICS. Herein, we describe the Portaclamp approach and report our indications and preliminary clinical experience so to define its role in VAMICS.  相似文献   
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Participation of human epididymal sperm coating antigens in fertilization   总被引:1,自引:0,他引:1  
A polyclonal antiserum directed against human sperm coating proteins of epididymal origin (anti-KCl) was tested for its ability to alter sperm function. Spermatozoa from normal ejaculates were selected by swim-up separation and capacitated by overnight incubation at room temperature. Exposure of these cells to anti-KCl (0.39 mg protein/ml), prior to their use in the hamster ova penetration test, reduced the penetration of denuded oocytes by 65% (P less than 0.005). Significant inhibitions of lesser magnitude were observed at lower serum concentrations (to 0.098 mg/ml). In an effort to understand the mechanism of this inhibition, other sperm function parameters thought to be related to oocyte penetration were studied. The inhibitory effect was exerted without noticeable changes in sperm motility (determined by the percentage of motile cells and their linear velocity), and in the absence of major sperm agglutination. Anti-KCl did not inhibit the occurrence of spontaneous or induced (by human follicular fluid) acrosome reaction in capacitated spermatozoa. In contrast, exposure to anti-KCl reduced the ability of capacitated spermatozoa to bind tightly to the hamster oolemma. None of these effects were elicited by a control preparation obtained from pre-immune rabbit sera. Exposure of zona-free oocytes to the antiserum did not alter their penetrability by normal sperm. These results suggest that the antigens recognized by anti-KCl participate in some specific step of the sperm-ovum interaction.  相似文献   
95.
Gallopamil is a calcium-channel antagonist with reported activity in experimental animals three to five times higher than that of verapamil. An automated high-performance liquid chromatographic (HPLC) method with fluorescence detection is described for the simultaneous determination of gallopamil and its metabolite norgallopamil in plasma. Gallopamil was well resolved from norgallopamil and other metabolites, allowing simultaneous quantitation of both drugs. The detection limit for both gallopamil and norgallopamil was 0.9 ng/ml. This method has been successfully used for the determination of gallopamil and norgallopamil following the administration of 25-, 37.5-, and 50-mg oral doses of drug.  相似文献   
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The effect of exhaustive exercise on the hepatobiliary transport of organic anions was investigated in rats. Animals were run on a rodent treadmill at 24 m/min up a 12% grade (152 +/- 15 min). Exercise resulted in significant hypoglycaemia (-46%) and increased plasma levels of lactate (+12%), together with a marked reduction of glycogen concentration in the liver (-72%). When bromosulphthalein was administered i.v., its maximal biliary excretion (Tm) was significantly reduced (-30%), and plasma and liver concentrations of the dye were increased (+31% and +56%, respectively). The decrease corresponded both to the excretion of the conjugated and unconjugated dye (-30% and -33%, respectively). Cytosolic glutathione S-transferase activity in the liver was not affected by exercise, but there was a significant reduction in the hepatic concentration of glutathione (-50%). The Tm of dibromosulphthalein was also significantly reduced (-36%) and its plasma and liver concentrations increased (+67% and +33%, respectively) in exercised rats. The results suggest that, in addition to the direct effect of liver glutathione depletion, other factors must be involved in the impairment of the biliary excretion of organic anions caused by exercise.  相似文献   
98.
The two-phase reconstruction of the mandible with a 2.7-mm-Martin-reconstruction-plate creates a tumor free period that is followed by bone grafting to the embedded plate. We have treated 61 patients following this pattern from 2000 to 2005, follow-up was done in 56. 14 patients had received radiotherapy of 70?Gy. 43 plates healed in without any complications. Until 2005 bone grafting had been performed in 18 patients, in ten patients the plate had been removed.  相似文献   
99.
Omphalocele is the most common congenital defect of the abdominal wall. Mortality rate is between 20 and 70% and early closure of the abdominal wall, within 10 days of life, is vital to the successful outcome of the surgical treatment. The authors describe the use of two bipedicled flaps of abdominal skin to correct the defect of the midline as soon as the reduction of all viscera has been accomplished.  相似文献   
100.
Juxtaoral organs known as organs of Chievitz are intramuscular embryonic structures found close to the angle of the mandible near the insertion of the pterygomandibular raphae. They are considered of neuroepithelial origin with no known function. We describe the first tumor of the organ of Chievitz which presented intraorally in a child. Immunohistochemically, the Chievitz nests showed positive reaction for vimentin, cytokeratins, and epithelial membrane antigen and ultrastructurally demonstrated cytoplasmic processes and intermediate filament bundles. These observations, together with light microscopic features, suggest that the epithelial nests of the organ of Chievitz are meningothelial rather than neuroepithelial. Received December 18, 1996; accepted March 13, 1997.  相似文献   
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