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91.
Harmful and protective roles of neutrophils in sepsis   总被引:5,自引:0,他引:5  
The current studies demonstrate protective and harmful effects of neutrophils (PMN) during experimental sepsis after cecal ligation and puncture (CLP). It is known that CLP induces signaling defects in blood PMN. When PMN were depleted 12 h after CLP, there were dramatic reductions in levels of bacteremia, evidence for reduced liver and renal dysfunction, sharp reductions in serum levels of cytokines (IL-1beta, IL-6, IL-10, TNF-alpha, and IL-2), and improved survival. In contrast, PMN depletion before CLP resulted in substantial increases in bacteremia and no evidence for attenuation of liver and renal failure dysfunction. These data suggest that at the onset of sepsis, PMN are important in regulating the levels of bacteremia, whereas after the onset of sepsis, as they lose innate immune functions, their presence is associated with higher levels of bacteremia and intensified organ dysfunction.  相似文献   
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BACKGROUND: The older proton pump inhibitor (PPI) omeprazole and the newer PPIs lansoprazole, rabeprazole, and pantoprazole are approved for the acute and maintenance treatment of gastroesophageal reflux disease (GERD). OBJECTIVE: On the basis of the results of randomized clinical trials, this study sought to estimate healing and relapse rates in acute and maintenance treatment of GERD with the newer PPIs compared with omeprazole, the histamine2-receptor antagonist ranitidine (the most frequent non-PPI comparator in studies of PPIs), and placebo. METHODS: A search of MEDLINE was conducted to identify randomized, controlled clinical trials that included a PPI in > or =1 treatment arm and assessed the healing of erosive esophagitis endoscopically. The primary outcome for studies of acute therapy was healing rate, and the primary outcome for studies of maintenance therapy was relapse rate. RESULTS: Fifty-three studies were identified, of which 38 involved acute therapy (12 excluded) and 15 maintenance therapy. None of the studies of pantoprazole met the inclusion criteria for maintenance therapy. The 8-week overall healing rate ratios in the comparison of newer PPIs with omeprazole 20 mg/d were as follows: lansoprazole 30 mg/d, 1.02 (95% CI, 0.98-1.06): rabeprazole 20 mg/d, 0.93 (95% CI, 0.87-1.00); and pantoprazole 40 mg/d, 0.98 (95% CI, 0.90-1.07). In the comparison of any PPI with ranitidine 300 mg/d, the ratios were as follows: lansoprazole, 1.62 (95% CI, 1.46-1.76); rabeprazole, 1.36 (95% CI, 1.20-1.54); pantoprazole, 1.60 (95% CI, 1.33-1.96); and omeprazole, 1.58 (95% CI, 1.41-1.78). Relapse rates over 1 year of treatment were similar between lansoprazole and rabeprazole. Compared with ranitidine, there were statistically significant differences in the rates of resolution of heartburn symptoms (P < 0.002), ulcer healing (P < 0.05), and relapse (P < 0.01). Similar results were seen in the comparison of PPIs with placebo in terms of rates of resolution of heartburn symptoms (P < 0.01), ulcer healing (P < 0.001), and relapse (P < 0.006). CONCLUSIONS: In this study, the newer PPIs were of similar efficacy to omeprazole in terms of heartburn control, healing rates, and relapse rates. All the PPIs were superior to ranitidine and placebo in healing erosive esophagitis and decreasing relapse rates.  相似文献   
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OBJECTIVES: Two studies are described addressing how anxiety, fear of pain, and catastrophizing impact on pain experience. METHODS: In study 1, 66 undergraduates (34 men, 32 women) completed measures of state and trait anxiety, fear of pain, and catastrophizing prior to participating in a cold pressor procedure. In study 2, 60 undergraduates (30 men, 30 women) completed the same measures and participated in dental hygiene treatment and rated the pain they experienced during a scaling procedure (removing deposits from the tooth surface). RESULTS: In both studies, fear of pain and catastrophizing were significantly correlated with pain intensity ratings, and fear of pain and catastrophizing were correlated with each other. Trait anxiety was correlated with catastrophizing but not with fear of pain or pain. Path analyses revealed significant paths from trait anxiety to state anxiety, from trait anxiety to catastrophizing, and from catastrophizing to pain intensity ratings. DISCUSSION: The findings suggest that although fear of pain and catastrophizing are related constructs, catastrophizing provides unique predictive ability for pain ratings, while fear of pain does not. Clinical and theoretical implications of these findings are discussed.  相似文献   
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The adoption of systems‐focused risk assessment techniques has not led to measurable improvement in the rate of patient harm. Why? In part, because these tools focus solely on understanding problems and provide no direct support for designing and managing solutions (ie, risk control). This second installment of a 2‐part series on rebalancing risk management describes a structured approach to bridging this gap: The Active Risk Control (ARC) Toolkit. A pilot study is presented to show how the ARC Toolkit can improve the quality of risk management practice.  相似文献   
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