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91.
Evaluation of: Luna CM, Bruno DA, García-Morato J et al. Effect of linezolid compared with glycopeptides in methicillin-resistant Staphylococcus aureus severe pneumonia in piglets. Chest 135(6), 1564–1571 (2009).

Methicillin-resistant Staphylococcus aureus (MRSA) has emerged as a major pathogen in nosocomial infections and accounts for a large proportion of nosocomial pneumonia. However, there are limited antibiotics available for the treatment of this serious and potentially lethal infection. Until recently, the only effective antibiotic was vancomycin, but the oxazolidinones, such as linezolid, have been shown to be a valuable addition to the arsenal of antimicrobial agents that can be used for MRSA pneumonia. Clinical trials have been conducted to compare vancomycin and linezolid head-to-head in pneumonia and, in post hoc subgroup analyses, showed that linezolid use was associated with improved survival. The ensuing debate over these results was dominated by two opinions; there were those who speculated on the mechanism by which linezolid achieved this benefit, namely attributing it to pharmacodynamics and pharmacokinetics, and others who criticized the methodology of the studies and questioned the validity of the results altogether. This study by Luna and colleagues was designed with several goals in mind. The first was to attempt to generate an animal model of MRSA pneumonia in piglets by duplicating techniques used in animal models of Gram-negative pneumonia. Then they studied the effect of three antibiotics (vancomycin, linezolid and teicoplanin) on outcomes in the same model, while simultaneously measuring antibiotic levels in the serum, bronchoalveolar lavage fluid and lung tissue, in an attempt to attribute differences in survival to pharmacological properties of the drugs used. Their results showed a survival benefit only for linezolid, despite the fact that all three antibiotics had levels above MIC in all the compartments sampled, leading them to speculate that linezolid may have improved outcomes by mechanisms not directly related to its antimicrobial actions.  相似文献   
92.
93.
Effective antimicrobial stewardship is an increasingly important concern for healthcare providers globally. Antibiotics are frequently prescribed for patients who develop sepsis in the intensive care unit and traditionally courses are prolonged, with uncertain benefit and probable harm. There is little evidence to support many guidelines recommending between 10 and 14 days, and a number of studies suggest substantially shorter courses of less than 7 days may suffice. Safely reducing course length is likely to depend on a number of preconditions, including thorough eradication of any septic foci; optimization of serum antibiotic concentrations, particularly when there is physiological derangement; and use of novel biomarkers such as procalcitonin. The critical care environment is well suited to this aim as patients are closely monitored. With these measures in place, it is reasonable to believe short antibiotic courses can safely be used for the majority of intensive care infections.  相似文献   
94.
With the expansion of hospice services, volunteers are being increasingly used to provide emotional, spiritual, and tangible support to the terminally ill and their significant others. Unfortunately, little has been published about the experiences of hospice volunteers. In this paper, we (1) propose a timely agenda for the development and refinement of hospice volunteer programs; (2) outline basic program criteria about which there is emerging consensus; (3) delineate pertinent issues in the screening, training, and job performance of hospice volunteers; and (4) indicate how the implementation of formal program regulations and operations and program evaluation may benefit service recipients and institutional providers.  相似文献   
95.
超声在新生儿肺炎诊断中的应用   总被引:1,自引:0,他引:1       下载免费PDF全文
新生儿肺炎作为新生儿常见疾病,严重危害新生儿健康,是导致其死亡的重要原因。目前临床诊断新生儿肺炎的主要方法为X线摄片。随着超声技术的发展,其在肺部疾病诊断中的应用也越来越多。本文就超声在新生儿肺炎的辅助诊断及治疗随访中的应用现状与进展进行综述。  相似文献   
96.
目的 分析血清维生素A(VA)、降钙素原(PCT)、血红蛋白(Hb)水平与急性期肺炎患儿病情严重程度的相关性.方法 回顾性收集2018年7月至2019年6月在我院就诊的急性期肺炎患儿临床资料83例,根据患儿的病情严重程度分为轻度组(n=33)、中度组(n=29)、重度组(n=21),收集同期于我院体检的正常儿童资料24...  相似文献   
97.
目的为探讨老年人肺癌院内获得性肺炎的临床特点、病原菌及耐药情况,为临床提供依据。方法分析72例老年人肺癌并发院内获得性肺炎的临床资料。结果老年人肺癌平均住院日期延长,化疗时不合理使用抗菌药物,发生院内获得性肺炎的机会最大。主要病原菌为G~-杆菌占80.70%,其中以铜绿假单胞菌、肺炎克雷伯氏菌为主,其次为表皮葡萄球菌占10.53%。病原菌对氨苄青霉素、哌拉西林、头孢菌素耐药性增加,对亚胺培南、万古霉素、阿米卡星敏感。病死率达30.56%。结论老年人肺癌免疫功能低下,住院日期延长,不合理使用抗生素是造成院内感染的主要因素。病原菌的耐药率呈增加趋势,病死率较高。  相似文献   
98.

甲状腺相关眼病(thyroid associated ophthalmopathy,TAO)是一种自身免疫性眼眶炎症性疾病,影像学检查是其重要的辅助检查手段。通过影像学检查能充分了解眶内病变,鉴别具有相似临床表现的眼眶疾病; 同时对TAO分期、辅助诊断压迫性视神经病变(compressive optic neuropathy,CON)也具有重要意义。  相似文献   

99.
The pharmacokinetic behavior of tobramycin and gentamicin was evaluated in 27 patients who had cystic fibrosis (CF). A previously studied, age-matched group of 334 patients who had been treated with gentamicin and who did not have CF served as controls. The CF patients, who ranged in age from 2 to 32 years and who had normal renal function, received 36 treatment courses with either tobramycin (19) or gentamicin (17) to treat Pseudomonas pneumonia. Serum concentrations were determined after a 1.5-mg/kg dose to compute half-life (t 1/2), elimination rate constant (k), and apparent volume of distribution (V). From these values, doses were calculated to produce steady-state peak concentrations of 8.0 micrograms/ml with a dosing interval of every six hours. For tobramycin the mean (+/- SD) t1/2 was 1.0 (0.4) hours, V was 0.18 (0.06) l/kg, total body clearance (TBC) was 2.19 (0.71) ml/min/kg, and the calculated dose was 8.2 (2.1) mg/kg/day. For gentamicin t1/2 was 1.1 (0.5) hours, V was 0.20 (0.06) l/kg, TBC was 2.28 (0.89) ml/min/kg, and the calculated dose was 8.8 (2.4) mg/kg/day. The pharmacokinetic parameters were not statistically different between the two drugs, but the mean values of t1/2 and TBC of CF patients differed significantly from those of the control group. The calculated doses were larger than the manufacturer's maximum recommended dose of 7.5 mg/kg/day for 63% of tobramycin and 71% of gentamicin treatment courses. A dosing interval change to every four hours would have been appropriate in 28 of the 36 treatment courses (78%).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
100.
BACKGROUND: The high proportions of lymphoid tissues are thought to be one of the underlying factors inducing severe allograft rejection following small bowel transplantation. Mesenteric lymph nodes (MLN) contained in the intestinal graft are not only a source of donor-derived professional antigen-presenting cells, but also offer a field for immune interaction between donor and host cells. We investigated immune responses in graft MLNs with or without FK506 to develop a novel strategy to control small bowel allograft rejection. MATERIALS AND METHODS: Heterotopic small bowel transplantations were performed from Brown Norway donors to Lewis recipients. Changes in population of lymphocytes, expressions of costimulatory molecules, apoptosis, and cytokine profiles in graft MLNs were evaluated. RESULTS: The increase in apoptotic cells and cytokine responses relating to rejection in the graft MLNs developed prior to those in graft jejunum. While donor lymphocytes in graft MLNs were rapidly replaced to host-derived lymphocytes independent of FK treatment, increase in CD8(+) T cells in host population was seen only in recipients without FK506 treatment. The expressions of B7 molecules on donor cells in graft MLNs were significantly lower in the recipients with FK treatment. CONCLUSIONS: Immune responses in graft MLNs have significant impact on the outcome of the small bowel allograft. Apoptosis of graft MLN cells was well correlated with and ahead of progression of acute rejection. Modulation of costimulatory molecules on donor-derived MLN cells in the allograft and specific suppression of host CD8(+) T cells are possible ways to control severe rejection after allogeneic small bowel transplantation.  相似文献   
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