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61.
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BACKGROUND: Smoking cigarettes and other forms of nicotine administration appear to blunt the perception of pain. Abrupt discontinuation of nicotine in nicotine-dependent patients appears to increase the perception of pain. The clinical importance of nicotine's effect on pain perception is not fully understood. OBJECTIVE: To determine whether smokers who abruptly discontinue smoking as a result of being hospitalized for coronary artery bypass graft (CABG) require more postoperative opiate analgesics than nonsmokers. METHODS: A retrospective review of patients who underwent a CABG was performed. Smokers (n = 20) were compared with nonsmokers (n = 69) with regard to opiate analgesic use during the first 48 hours postoperatively. The use of nonopiate sedatives was also compared between the groups. RESULTS: When normalized for weight and body mass index, smokers required 23% and 33%, respectively, more opiate analgesics than did nonsmokers (p = 0.027 and 0.023, respectively). The percentage of patients who received benzodiazepines postoperatively was similar in the 2 groups. CONCLUSIONS: In this study, smokers deprived of nicotine required a greater amount of opiates in the first 48 hours after CABG than did nonsmokers. Healthcare providers need to be aware of the potential for increased narcotic requirements among nicotine-deprived smokers. Further study is needed to determine whether nicotine replacement lessens the requirement for postoperative analgesics in smokers.  相似文献   
63.
Escherichia coli and Enterococcus faecalis strains isolated from anal swabs of clinically healthy dogs were examined for the presence of acquired antimicrobial resistance. The strains originated from dogs of 92 different owners and from eight breeding kennels. The purpose of the present study was to evaluate the resistance situation in the intestinal flora of the dog to assess the possible role of the dog flora as a reservoir of antimicrobial resistance. Multiple resistance was rarely found in E. coli strains collected from individually owned dogs, in contrast with strains from kennel dogs. Resistance to ampicillin, trimethoprim, and sulfamethoxazole was significantly less prevalent in E. coli from privately owned dogs than in strains from kennel dogs. Resistance rates against tetracycline and macrolides were unexpectedly high in E. faecalis strains. Two and three E. faecalis strains from individually owned dogs and kennel dogs, respectively, were resistant to gentamicin, an antibiotic often used for treating enterococcal infections in humans. This study demonstrates that resistance percentages may fluctuate with the choice of dog population. The observed antimicrobial resistance percentages indicate that the flora of healthy dogs may act as a reservoir of resistance genes.  相似文献   
64.
Expression of costimulatory molecules by recombinant poxviruses is a promising strategy for enhancing therapeutic vaccines. CD40-CD40L interactions are critical for conditioning dendritic cells (DC) and priming T- and B-cell immunity. We constructed a vaccinia virus expressing murine CD40L (rV-CD40L) and studied its immunomodulatory properties in vitro. Direct DC infection with control vaccinia or psoralen/UV-inactivated rV-CD40L stimulated high levels of interleukin 12 (IL-12) release. However, replication-competent rV-CD40L did not stimulate IL-12 under similar conditions. We observed a high level of CD40L protein on purified viral particles and demonstrated that induction of IL-12 by nonreplicating rV-CD40L was blocked by anti-CD40 antibodies suggesting that functional CD40L on viral particles contributed to alterations in IL-12 synthesis.Since cross-presentation of tumor-associated antigens by DC is augmented by viral infection of tumor cells, we infected MC38 murine colon carcinoma cells with rV-CD40L. Infected cells stimulated IL-12 secretion by DC and proliferation of B cells and DX5(+) (NK/NKT) cells through direct CD40-CD40L interaction. A subpopulation of NKT cells expressing CD40 (NK1.1(+), CD3(lo)) appeared to be a major effector population responding to MC38/rV-CD40L. These results highlight the complex immune regulatory effects of rV-CD40L defined by the cumulative effects of CD40L expression, presence of CD40L protein in viral particles, and the replication potential of the virus.  相似文献   
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66.
Case 55: fetus in fetu   总被引:2,自引:0,他引:2  
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68.
PURPOSE: To determine whether half-Fourier MR image acquisition technique can provide similar information to that of conventional MR acquisition technique for evaluation of meniscal tears. MATERIALS AND METHODS: We studied 101 menisci in 52 patients who were referred for evaluation of meniscal tears. Sagittal MR images of the knee were obtained for all patients by using proton density and T2-weighted SE sequences on a 1-T clinical system. The half-Fourier technique and conventional technique were used for all patients. All other imaging parameters were identical for both sequences (TR/TE=2400/20,70; 3 mm slice thickness; 200 x 256 matrix; field of view, 200; one signal acquired). Both sets of images were filmed with standard window and level settings. Images were randomised and interpreted independently by two radiologists for the presence of meniscal tears. Images were also subjectively assessed for image quality using a five-point grading scale. RESULTS: On half-Fourier images, Reader 1 interpreted 23 menisci as torn, compared to 28 for Reader 2. On conventional images, Reader 1 interpreted 24 menisci as torn, compared to 26 for Reader 2. Agreement between interpretation of the conventional and that of the half-Fourier images was 99% for Reader 1, and 98% for Reader 2. Agreement between readers for the half-Fourier images was 95%, and for the conventional images 96%. No statistically significant difference was found in the subjective evaluation of image quality between the conventional and half-Fourier images. CONCLUSION: The half-Fourier acquisition technique compares favourably with the conventional technique for the evaluation of meniscal tears.  相似文献   
69.
Pregnancy-induced hypertension is one of the complications that obstetricians fear most due to its sudden appearance, its changing clinical presentation, its rapid evolution, and its association with high fetal and maternal morbidity and mortality. Because of these reasons, preeclampsia has been studied widely. But although the search for answers to many questions about its etiopathogenesis and physiopathology has led to numerous researches, after many years of studies and efforts there still exist obscure and enigmatic aspects about them. Today, various risk factors for the development of this entity have been identified, and a combination of different hypotheses has been proposed to try to find an approximation to the real solution for this problem, which could probably lead to better therapeutic management.  相似文献   
70.
Thirty-two Enterococcus faecium strains and 33 Enterococcus faecalis strains were tested for their susceptibility to the ionophore antibiotics salinomycin, narasin, monensin, and lasalocid. Enterococcal strains originated from poultry in which these products are in use as coccidiostats, and from pigs in which these products are allowed as growth promoters. Resistance against salinomycin and narasin in enterococci was frequent among poultry strains, whereas in pig strains, resistance was less common. No resistance was found against monensin and lasalocid. Full cross resistance between salinomycin and narasin was evident. There was no cross resistance between these two ionophores and monensin and lasalocid.  相似文献   
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