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排序方式: 共有1488条查询结果,搜索用时 15 毫秒
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Mamta Sharma Dorine Berriel-Cass Joseph Baran 《Infection control and hospital epidemiology》2004,25(6):468-471
OBJECTIVE: Surgical-site infection (SSI) is a serious and costly complication following coronary artery bypass graft (CABG). We analyzed surgical factors, microbiology, and complications at a 608-bed community teaching hospital to identify opportunities for prevention. METHODS: All patients undergoing CABG procedures from June 1997 through December 2000 were analyzed. Hospital records and postdischarge surveillance data were reviewed for demographics, surgical information, timing and classification of infection, microbiology, and bacteremic events. RESULTS: Of 3,443 patients undergoing CABG, sternal SSI developed in 122 (3.5%); 71 (58.2%) were classified as superficial SSI and 51 (41.8%) as deep SSI. Surgical antimicrobial prophylaxis was employed in all cases. On average, infection occurred 21.5 days (range, 4 to 315) after CABG. Most cases were diagnosed on readmission (59%); 20 cases (16%) were identified by postdischarge surveillance. Microbiological data were positive in 109 (89.3%), with a single pathogen implicated in most (86.2%). Gram-positive cocci were most frequently recovered (81%); gram-negative bacilli (17%), gram-positive bacilli (1%), and yeast (1%) were less common. Staphylococcus aureus was the most frequently isolated pathogen (49%). Bacteremia was noted in 22 instances (18%). It was significantly associated with deep SSI (P =. 002) and identified only in S. aureus cases. CONCLUSIONS: SSI complicated 3.5% of the procedures. S. aureus was implicated in most of the cases and was significantly associated with deep SSI. It was the only pathogen associated with secondary bacteremia. In addition to standard guidelines, targeted methods against S. aureus should help reduce the overall rate of SSI. 相似文献
3.
D T Baran A M Sorensen T W Honeyman R Ray M F Holick 《Journal of bone and mineral research》1990,5(5):517-524
1 alpha,25-Dihydroxyvitamin D3 rapidly increases cytosolic calcium and alters membrane phospholipid metabolism in hepatocytes. To define the causal relationship between these events, we examined the effects of 1 alpha,25-dihydroxyvitamin D3 on 32P-labeled lysophosphatidylinositol levels and cytosolic calcium as affected by pertussis toxin and 1 beta,25-dihydroxyvitamin D3, the biologically inactive analog. 32P-labeled lysophosphatidylinositol was determined by two-dimensional thin-layer chromatography. Cytosolic calcium was measured in cells loaded with quin-2AM. Within 5 min, 1 alpha,25-dihydroxyvitamin D3 increased hepatocyte cytosolic calcium by 31% (p less than 0.05) and 32P-labeled lysophosphatidylinositol by 38% (p less than 0.05). Pertussis toxin inhibited the hormone-induced rise in cytosolic calcium but not the increase in 32P-labeled lysophosphatidylinositol. Exposure to exogenous lysophosphatidylinositol for 5 min increased cytosolic calcium by 40% (p less than 0.05), an effect that was also inhibited by pertussis toxin. 1 beta,25-Dihydroxyvitamin D3 had no effect on either hepatocyte cytosolic calcium or 32P-labeled lysophosphatidylinositol but prevented the 1 alpha,25-dihydroxyvitamin D3-induced increments. The results suggest that a G protein sensitive to pertussis toxin is required for the transduction of the lysophosphatidylinositol signal but not the generation of the signal. The ability of 1 beta,25-dihydroxyvitamin D3 to inhibit the 1 alpha,25-dihydroxyvitamin D3-induced changes in phospholipids suggests that the epimer may compete with 1 alpha,25-dihydroxyvitamin D3 for an initiating receptor. 相似文献
4.
Vendeville B.; Baran D.; Gascon-Barre M.; Rubin E.; Luu T.; Vallieres S. 《Nephrology, dialysis, transplantation》1995,10(11):2020-2026
BACKGROUND.: Mercuric chloride (HgCl2 induces a lymphoproliferative disorderand autoimmune glomerulonephritis in Brown Norway (BN) rats.This syndrome is the consequence of T cell-dependent polyclonalB cell activation and autoantibody production. We have previouslyshown that HgCl2-induced autoimmune perturbations can be preventedin BN rats by the administration of cyclosporin A (CsA). Themost potent vitamin D3 metabolite 1,25(OH)2 D3 (Vit D3) sharescertain immunomodulatory properties with CsA. We therefore choseto compare the effects of Vit D3 to those of CsA in BN ratstreated with HgCl2 in order to establish whether Vit D3 eitheralone or in combination with CsA can attenuate an autoimmunesyndrome in vivo. METHODS.: BN rats were treated with HgCl2 according to a standard protocol.Subgroups of rats were also given CsA alone, Vit D3 or syntheticanalogues of Vit D3 alone, or combinations of both agents. Differentdoses and routes of administration were compared. The followingmarkers of disease activity were evaluated: mortality, peakproteinuria, serum IgE concentrations, and renal immunoglobulindeposition. RESULTS.: Disease activity was markedly attenuated in all rats treatedwith CsA alone. Vit D3 and certain of its synthetic analoguesadministered alone also tempered the autoimmune process, butto a lesser extent than did CsA. The effect of CsA alone wasso potent, that no additive or synergistic effects could bedemonstrated when CsA was administered in combination with VitD3. CONCLUSIONS.: Despite similar described immunomodulatory effects in vitro,CsA is clearly more effective than Vit D3 in preventing HgCl2autoimmune disease in BN rats. This suggests that there is adifference in the cellular targets of these two agents in vivo,and/or a difference in the potency with which HgCl2-triggeredimmune activation is suppressed. 相似文献
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6.
Teresa Baran Andrzej Duda Stanistaw Penczek 《Macromolecular chemistry and physics.》1984,185(11):2337-2346
The anionic polymerization of exo-3,4,5-trithiatetracyclo[5.5.1.O2,6.O8,12]tridec-10-ene ( 1 ) in bulk and/or in aromatic solvents (benzene, toluene) was studied. The polymerization was initiated with sodium benzenethiolate (sodium cation complexed with dibenzo-18-crown-6). Polymers with high-molecular weights were obtained (M n ≈ 105, osmometrically). The polymerization was found to be living and reversible; the equilibrium monomer concentration increases with the temperature. The ceilling temperature was estimated as 167°C. The thermodynamic data of the polymerization in toluene was determined and compared with those of the polymerization of exo-3,4,5-trithiatricyclo[5.2.O2,6]decane. The standard enthalpy ΔH = ?(6,6 ± 0,6)kJ · mol 1 and entropy ΔS = ?(29,3 ± 2,1)J · mol 1 · K 1 of the polymerization of 1 were evaluated from the temperature dependence of the equilibrium monomer concentration, determined dilatometrically. 相似文献
7.
Łuszczek W Kubicka W Cislo M Nockowski P Mańczak M Woszczek G Baran E Kuśnierczyk P 《Immunology letters》2003,85(1):59-64
Association of psoriasis vulgaris with HLA-C is not equally strong in different human populations. It has not yet been studied in Polish patients at DNA level, but only by serology that is inadequate for HLA-C. Therefore, we examined the distribution of HLA-C alleles by means of low resolution PCR-SSP in 102 Polish psoriatics and 123 healthy controls. We have found significantly higher representation of HLA-Cw*06 (odds ratio, 18.73; P(cor)<0.001) and significantly lower representation of HLA-Cw*07 (odds ratio, 0.41; P(cor)<0.038) in patients than in controls. Association of HLA-Cw*06 with psoriasis was even stronger in early age at onset (0-20 years) group: odds ratio, 77.71; P(cor)<0.001. Therefore, our population seems to belong to those with strong association of psoriasis with HLA-Cw*06. 相似文献
8.
Gene therapy with an E2F transcription factor decoy inhibits cell cycle progression in rat anti-Thy 1 glomerulonephritis 总被引:1,自引:0,他引:1
9.
个体化下肢小腿假肢接受腔设计的生物力学评价技术研究 总被引:3,自引:0,他引:3
作为传递体重、固定假肢的部件 ,接受腔对于小腿假肢使用的舒适性和方便程度有决定性的作用。本研究建立了基于有限元应力分析的小腿假肢生物力学评价技术平台 ,实现了小腿残端 /接受腔 3D几何建模与信息交互、三维有限元自动建模及应力分析。 3D模型与信息交互的实现基于得到广泛支持的OpenGL技术 ,有限元模型的构建采用了专门针对小腿残端 /接受腔结构特点的自动建模方法 ,通过构建档案数据库系统作为整个系统的操作平台。该技术平台可与现有的CAD/CAM系统相结合 ,为接受腔的个体化设计提供生物力学定量化依据。其临床应用将改善传统的设计流程 ,提高设计效率。同时 ,它也是未来构建接受腔设计专家 /智能系统的基础。 相似文献
10.