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1.
The beStent is a new stainless steel, balloon-expandable mesh stent which has a unique serpentine design. Rotation of the unique low stress junctions upon expansion leads to orthogonal locking of the wires, maximizing radial strength and assuring zero shortening. The stent has delineating gold markers which assure precise positioning. We aim to present the initial acute results in a pilot registry for stent evaluation. Two hundred eighty-four stents were used in a total of 217 patients (age 57.9 ± 3.10 years; 178 males; 39 females) in seven centers, for variable indications. Stents of 15-, 25-, and 35-mm length were used. The arteries treated were the left anterior descending (n = 112, 42%), circumflex (n = 54, 20.2%), right coronary (n = 95, 35.5%), left main (n = 1, 0.4%), and vein graft (n = 5, 1.9%). Lesion types were: A in 42 patients (16.5%); B1 in 53 patients (20.7%); B2 in 81 patients (31.8%); and C in 79 patients (31%). One hundred fifty-nine patients required one stent, 40 patients required two stents, and 18 patients required three or more stents. Anticoagulation protocol included procedural heparin with aspirin with/without ticlopidine. Smooth angiographie results were obtained in all cases with no plaque herniation. Acute angiographic success was obtained in 97% of the patients, and acute clinical success in 95% of the patients. Complications within 30 days were: 3 deaths (1.4%) (2 noncardiac); 2 (0.9%) myocardial infarctions; and 2 (0.9%) stent thromboses. Therefore, the beStent is useful in treatment of complex lesions of variable length and complexity, providing excellent acute results with a low complication rate, in spite of unfavorable basic clinical and angiographie characteristics.  相似文献   
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Sardinian alcohol-preferring (sP) rats have been selectivelybred for high ethanol preference and consumption over 16 yearsand 39 generations. The present paper briefly reviews some recentstudies from this laboratory characterizing ethanol drinkingbehaviour in this rat line. Under the two-bottle regimen offree choice between 10% (v/v) ethanol and water, sP rats consumedaily >4 g of ethanol/kg and avoid water almost completely.Relevant features of ethanol drinking behaviour in sP rats are:(a) attainment of high ethanol intake from the first day ofexposure to ethanol, suggestive of an immediate disclosure andacquisition of ethanol reinforcement; (b) titration of dailyethanol intake in distinct binges during the nocturnal phaseof the light/dark cycle, indicative of their ability to regularizeboth ethanol dose and administration time; (c) achievement ofpharmacologically relevant blood ethanol levels at each drinkingepisode; (d) substitution of the calories provided by ethanolfor a part of those taken from food; (e) maintenance of constantethanol intake (in g/kg/day) in the presence of ethanol concentrationsvarying from 7 to 30% (v/v). These results suggest that voluntaryethanol intake in sP rats is sustained by the search for specificpharmacological effects of ethanol. Anxiolysis is likely tobe one of these effects; indeed, voluntarily consumed ethanolreversed the innate, high levels of anxiety in sP rats. Theseresults portray sP rats as a valid model for investigating theassociation between ethanol drinking and anxiety. Finally, thebreeding programme as well as results of neurochemical studiesare also described.  相似文献   
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In order to explore the influence of acetaldehyde (AcH) metabolismon the voluntary ethanol intake of genetically low (UChA) andhigh (UChB) ethanol consumer rats, the AcH disappearance rate(ADR) after incubation with homogenates and subcellular fractionsfrom liver and brain was determined. In addition, the effectof disulfiram pretreatment on AcH metabolism was studied. Maleadult rats of both strains were used. ADR was assayed in totalhomogenates, and in mitochondrial as well as 9000 g supernatantfractions of liver and brain. AcH was measured by gas chromatography.In some experiments, rats were pretreated with disulfiram (300mg/kg po) 24 hr before the studies. The result showed no straindifference in ADR in homogenates or subcellular fractions ofliver from untreated rats, but for disulfiram pretreated ratsa significantly lower decrease of ADR in samples from UChB comparedto UChA rats was observed. This result is consistent with alower peak AcH level in UChB compared to UChA rats after a loadof ethanol (60 mmole/kg ip). Concerning brain homogenates, ahigher ADR was observed in homogenates and crude mitochondrialfractions of UChB than of UChA rats. This difference was notobserved when the incubation was performed without adding NADor in the absence of oxygen. These results provide evidenceof strain differences in mitochondrial AcH metabolism, the natureand origin of which deserve further study.  相似文献   
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We evaluated membrane expression and function of complement receptors CR1 and CR3 on neutrophils from 27 HIV-positive (HIV+) subjects (14 in the CDC class III and 13 class IV) as well as their modulation in vitro by recombinant tumour necrosis factor-alpha (rTNF-alpha) and granulocyte-macrophage colony stimulating factor (rGM-CSF). While CR1 was expressed at similar levels on neutrophils from controls and HIV+ subjects, CR3 expression was significantly higher in CDC class IV subjects than in healthy controls. CR1 and CR3 expression was significantly increased after treatment of neutrophils with both cytokines, without differences between controls and HIV+ subjects. Similarly, the superoxide anion (O2-) production in response to C3-coated zymosan (C3zy) was significantly enhanced on neutrophils from CDC class IV subjects when compared with controls. rGM-CSF and rTNF-alpha treatment significantly enhanced the spontaneous as well as C3zy-stimulated O2- production by neutrophils from controls and CDC class III subjects, and induced an upward trend in the CDC class IV group. These results indicate that the neutrophils of HIV+ patients are preactivated in vivo but they also indicate that these cells may correctly respond to a subsequent particulate stimulus as well as to activating cytokines. Our findings suggest that desensitization or functional exhaustion of complement receptors are not implicated in the abnormalities observed on neutrophils from HIV+ patients.  相似文献   
7.
ABSTRACT: The injection of the spleen mononuclear (SpM) cells, obtained from rats rendered unresponsive to autoantigen of rat male accessory glands (RAG) by pretreatment with low doses of purified fraction of RAG (containing the autoantigen), into normal syngeneic recipients markedly prevented the development of delayed type hypersensitivity (DTH) reaction to the autoantigen (suppression of the induction) (p < 0.001). The humoral response was not altered. The control animals were rat receptors of spleen mononuclear cells from donor rats pretreated with rat lung saline extract or 0.15 M NaCl. In contrast, the transference of SpM cells from donor rats pretreated with low doses of autoantigen prior to the immunization to rats previously immunized, did not modify the expression of the immune response against the autoantigen when compared with control rats. The suppression of the induction of DTH response was also obtained when prior to the immunization, the recipients received T-cell-enriched SpM cell population from unresponsive animals (p < 0.001), but not when they were injected with B-cell-enriched SpM cells. These results suggest that suppressor T cells capable of controlling induction of the autoimmune response against RAG autoantigen might be one of the immunoregulatory mechanisms that are activated when soluble autoantigen of RAG enter into circulation.  相似文献   
8.
Selective strategies in food webs   总被引:1,自引:0,他引:1  
Food webs are described as control systems where the controlsare chosen according to given myopic strategies. In particular,strategies describing selective feeding and selective escapeare defined. The existence of optimal myopic solutions and theiruniqueness are discussed. Computer simulations modelling ‘switching’are given for a one-predator—two-prey system.  相似文献   
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This study aimed to assess the psychological status of men with haemophilia and HIV infection and to monitor changes in psychlogical status over time, in order to evaluate the need for psychological support. The study included 24 HIV seropositive men and a control group of 21 HIV seronegative men who attended the Haemophilia Centre in Bari (Italy). Subjects underwent psychological tests (STAl-Y: State and Trait Anxiety Inventory; SDS: Self-Rating Depression Scale) and completed a questionnaire on the emotional impact of AIDS. Assessment was repeated at 6-monthly intervals over a 2-year period. Contrary to expectation, HIV seronegative men with haemophilia had worse anxiety and depression scores, reported more confusion and fear, and had more reluctance towards the use of blood products (despite their present safety) than HIV seropositives. Possible reasons for these findings are considered, and their implications for clinical practice discussed.  相似文献   
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