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81.
82.
Chih-Yu Chi Wing-Wai Wong Chang-Phone Fung Kwok-Woon Yu Cheng-Yi Liu 《Journal of microbiology, immunology, and infection》2004,37(1):16-23
Methicillin-resistant Staphylococcus aureus (MRSA) is an important nosocomial pathogen which has been isolated with increasing frequency in recent decades. Community-acquired MRSA (CA-MRSA) infections have also become increasingly important in recent years. This study retrospectively analyzed the risk factors, duration of hospitalization, yearly trend and seasonal variation in prevalence, and antibiotic susceptibility of isolates of community-acquired S. aureus (CASA) bacteremia and CA-MRSA bacteremia from patients treated in a teaching hospital in northern Taiwan. A total of 104 clinical isolates of CASA bacteremia were collected between January 1999 and December 2001. Among these, 35 (33.7%) were identified as MRSA. After multivariate analysis, the independent risk factors for developing CA-MRSA bacteremia were diabetes mellitus (p=0.028), chronic obstructive lung disease (p=0.037), and renal insufficiency (p=0.041). Only 6 (17.1%) patients in the MRSA group had no identified risk factors. Most of the isolates of CA-MRSA had a high degree of resistance to most antibiotics, including clindamycin (71.4%), trimethoprim-sulfamethoxazole (65.7%), and chloramphenicol (41.2%). No major trend or seasonal variation in the prevalence was found during the study period. No difference in mortality related to resistance pattern was found. Although CA-MRSA is not the major pathogen in community-acquired bacteremia, it should be included in the differential diagnosis of Gram-positive bacterial bloodstream infection, especially in those patients with risk factors. Early empiric therapy with glycopeptides in these patients may reduce morbidity and mortality. 相似文献
83.
BACKGROUND: (R)- and (S)-Enantiomers of albuterol likely exert differential effects in patients with asthma. The (R)-enantiomer binds to the beta2-adrenergic receptor with greater affinity than the (S)-enantiomer and is responsible for albuterol's bronchodilating activity. (S)-Albuterol augments bronchospasm and has proinflammatory actions. OBJECTIVE: The study aim was to determine whether the (S)-enantiomer, in contrast to the (R)-enantiomer, has adverse effects on allergic airway inflammation and hyperresponsiveness in a mouse asthma model. METHODS: Mice sensitized to ovalbumin (OVA) intraperitoneally on days 0 and 14 were challenged with OVA intranasally on days 14, 25, and 35. On day 36, 24 hours after the final allergen challenge, the effect of the (R)- and (S)-enantiomers of albuterol (1 mg x kg(-1) x d(-1) administered by means of a miniosmotic pump from days 13-36) on airway inflammation and hyperreactivity was determined. RESULTS: In OVA-sensitized/OVA-challenged mice, (R)-albuterol significantly reduced the influx of eosinophils into the bronchoalveolar lavage fluid and airway tissue. (R)-Albuterol also significantly decreased airway goblet cell hyperplasia and mucus occlusion and levels of IL-4 in bronchoalveolar lavage fluid and OVA-specific IgE in plasma. Although (S)-albuterol significantly reduced airway eosinophil infiltration, goblet cell hyperplasia, and mucus occlusion, it increased airway edema and responsiveness to methacholine in OVA-sensitized/OVA-challenged mice. Allergen-induced airway edema and pulmonary mechanics were unaffected by (R)-albuterol. CONCLUSION: Both (R)- and (S)-enantiomers of albuterol reduce airway eosinophil trafficking and mucus hypersecretion in a mouse model of asthma. However, (S)-albuterol increases allergen-induced airway edema and hyperresponsiveness. These adverse effects of the (S)-enantiomer on lung function might limit the clinical efficacy of racemic albuterol. 相似文献
84.
Ho Chang Kuo Chih Lu Wang Chi Di Liang Hong Ren Yu Hsin Hsu Chen Lin Wang Kuender D Yang 《Journal of microbiology, immunology, and infection》2007,40(5):395-400
BACKGROUND AND PURPOSE: This study was conducted to investigate whether changes in the complete blood count (CBC)/differential count (DC) and C-reactive protein (CRP) were correlated to Kawasaki disease (KD) with coronary artery lesions (CALs). METHODS: A retrospective analysis was performed of all children with KD at Chang Gung Memorial Hospital at Kaohsiung from 2001 to 2006. KD patients were divided into those with and without CALs for testing of correlations with changes in CBC/DC and CRP levels. RESULTS: A total of 147 patients were enrolled for this analysis. Serial CBC/DC and CRP measurements and echocardiographic data for determination of CAL formation were obtained before and after intravenous immunoglobulin (IVIG) treatment. There were 44 (29%) KD patients having CAL formation (>3 mm in diameter of internal lumen). There was no significant difference in terms of age distribution and major diagnostic criteria between KD patients with and without CALs. Male KD patients, however, had a significantly higher rate of CAL formation (p=0.009). In multivariate logistical regression analysis, persistent monocytosis after IVIG treatment was the only factor significantly correlated to CAL formation (p=0.003). CONCLUSIONS: Of the febrile routine measurements of CBC/DC and CRP in KD, persistent monocytosis after IVIG treatment was correlated to CAL formation. Further studies to clarify the mechanism of monocytosis may help prevent the CALs of KD. 相似文献
85.
抗T细胞单克隆抗体对再生障碍性贫血患者TNF和IL—2水平的影响 总被引:2,自引:0,他引:2
为探讨抗T淋巴细胞克隆抗体对再生障碍性贫血患者免疫功能的调节作用,采用放射免疫检测25例AA患者McAb-T治疗前后血清肿瘤坏死因子和白细胞介素-2(IL-2)水平及其中10例周围血单个核细胞体外诱生TNF和IL-2水平的变化。 相似文献
86.
Fang Chi Oliver Nolte Carina Bergmann Margaret Ip Regine Hakenbeck 《International journal of medical microbiology : IJMM》2007,297(7-8):503
A paradigm for Streptococcus interspecies gene transfer is represented by the mosaic pbp genes encoding the target enzymes for beta-lactam antibiotics, the penicillin-binding proteins, in Streptococcus pneumoniae. We investigated a collection of oral streptococci from three continents by comprehensive multi-locus sequence typing analysis in order to trace the origin of a mosaic block belonging to a dominant family of mosaic pbp2x implicated in penicillin resistance of S. pneumoniae. One widespread family of mosaic pbp2x occurred in all three distinct clusters of S. pneumoniae, Streptococcus mitis and Streptococcus oralis, documenting independent inter- and intraspecies recombination events. Moreover, potential ancestor genes of this mosaic block could be identified in two penicillin-susceptible S. mitis strains from South Africa and Spain, facilitating the identification of pbp2x mutations relevant for resistance development. 相似文献
87.
不同来源乙肝表面抗原的细胞免疫学对比研究 总被引:3,自引:1,他引:3
目的 研究不同来源乙肝表面抗原诱导CD8 抗原特异性的细胞毒T淋巴细胞反应(CTL)的差异及T细胞产生细胞因子的能力 ,从而对各种来源乙型肝炎表面抗原 (HBsAg)的免疫原性有更充分的评价。方法 不同来源HBsAg分别免疫BALB c小鼠 ,于免疫后不同时间制备脾脏单个核细胞 (MNC) ,再以相应的HBsAg体外刺激 ,酶联免疫方法 (ELISA)测定细胞因子分泌水平 ;以Na2 5 1CrO4标记靶细胞 ,测定CTL反应活性 ;应用流式细胞仪分析T细胞亚群。结果 HM HBsAg免疫小鼠 10d后的脾细胞产生IFN γ水平最高 ,而在免疫后 2 0d和 2 5d ,IL 2的水平显著高于其它各组 ,CD3 分子脾淋巴细胞显著高于其它各实验组 (P <0 .0 5) ;plasma HBsAg免疫小鼠的脾淋巴细胞产生IFN γ和IL 2水平较低 ,但在免疫 2 5d对P815 HBs的杀伤性最强 ;HM HBsAg和SSC HBsAg免疫后CD4 CD8- 脾淋巴细胞比例显著增高 (P <0 .0 5) ;CD4- CD8 细胞所占百分比各组间及与空白对照组间差异无显著性 (P >0 .0 5)。结论 不同来源HBsAg诱导的细胞免疫反应类型和程度不同 相似文献
88.
BACKGROUND: Impaired implantation in assisted reproduction cycles with high serum estradiol (E(2)) concentrations may be related to suboptimal endometrial perfusion. Endometrial and subendometrial blood flow were compared between excessive responders (serum E(2) on the day of HCG >20 000 pmol/l) and moderate responders (E(2) < or =20 000 pmol/l). METHODS: Three-dimensional (3D) ultrasound examination with power Doppler was performed 2, 4 and 7 days after HCG in 32 patients who did not have embryo transfer in order to measure endometrial thickness, pulsatility index (PI)/resistance index (RI) of uterine vessels, and endometrial volume, vascularization index (VI)/flow index (FI)/vascularization flow index (VFI) of endometrial and subendometrial regions. RESULTS: Excessive responders tended to have lower endometrial and subendometrial VI/VFI on HCG +2 and more absent endometrial/subendometrial blood flow. They had significantly higher endometrial FI and subendometrial VFI than moderate responders on HCG +7. Only in the excessive responder group, uterine PI/RI declined significantly from HCG +2 to HCG +7 and endometrial VI/VFI increased significantly from HCG +4 to HCG +7. CONCLUSION: Changes in uterine Doppler flow indices, and endometrial and subendometrial 3D power Doppler flow indices during the early luteal phase were significantly different between moderate and excessive responders. 相似文献
89.
Herein reported is a case of congenital malignant melanoma in a premature male baby from a 25-year-old healthy mother who was found to have hydramnios at the 29th week of gestation. The pregnancy was interrupted because of a large posterior neck mass detected by ultrasonography. The large neck mass of the baby was a malignant melanoma involving deep dermis and subcutaneous tissue. The skin over the mass showed a large area of pigmentation with hairs and the pigmentation involved the occipital scalp and posterior neck. Microscopically, the tumor cells were monotonous and showed polygonal and epithelioid appearance with prominent nucleoli indicative of malignant melanoma of a minimal deviation variety. Neither junctional components nor benign dermal nevus cells were noted. There were no distant metastasis or underlying leptomeningeal melanosis. This tumor is presumed to have developed from either preexisted congenital giant pigmented nevus with loss of benign components or de novo origin. 相似文献
90.
评价用聚乙二醇系列的表面改性剂PEG、F127及PELA改性的纳米羟基磷灰石/聚乳酸复合材料的亲水性和溶胀性,先对纳米羟基磷灰石进行表面改性处理后,再综合用传统的溶液共混、流延法及热压法将改性的和未改性的纳米羟基磷灰石分别与聚乳酸制备成复合薄膜。检测结果表明:改性剂分别被涂敷于纳米羟基磷灰石上,改性处理能够改善纳米颗粒在基材内的分布;改性的纳米羟基磷灰石/聚乳酸复合材料比未改性的对比材料的表面接触角小、表面能大、亲水性好、溶胀度大,达到饱和溶胀度的时间长。改性的纳米羟基磷灰石比未改性的羟基磷灰石改善基体聚乳酸的亲水性和溶胀性效果更显著。 相似文献