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排序方式: 共有2125条查询结果,搜索用时 15 毫秒
21.
Duffy AJ Nolan B Sheth K Collette H De M Bankey PE 《The Journal of surgical research》2000,90(1):51-57
BACKGROUND: Altered transendothelial migration and delayed apoptosis of neutrophils (PMN) have been implicated as contributing to infection in patients with gram-negative sepsis. Macrophage inflammatory protein 2 (MIP-2) signals PMN immigration and may alter other PMN functions. We tested the hypothesis that sequential endotoxin challenge in vivo alters PMN apoptosis and chemotactic responses. MATERIALS AND METHODS: Endotoxemia was induced in male Wistar rats (250 g) via intraperitoneal (IP) administration of LPS (4 mg/kg). After 18 h, intratracheal (IT) injection of LPS (400 microg/kg) was performed. Control animals received saline injections. Four hours after IT-LPS, circulating and bronchoalveolar lavage (BAL) PMN were isolated. PMN yields were calculated, and apoptosis was quantified after 18 h in culture by annexin V-fluorescein isothiocyanate FACS analysis. BAL MIP-2 concentrations were determined by ELISA. PMN chemotaxis to MIP-2 and IL-8 was determined using a fluorescent in vitro migration assay. RESULTS: Endotoxemia (IP-LPS) significantly decreases BAL PMN yield in response to an in vivo IT-LPS challenge. IT-LPS inhibits BAL PMN apoptosis to the same extent as sequential IP/IT-LPS. Alveolar MIP-2 concentrations are similar in the two groups. In vitro migration to IL-8 and MIP-2 was inhibited in PMN from endotoxemic versus control animals. CONCLUSIONS: These data demonstrate that endotoxemia inhibits PMN migration despite similar MIP-2 concentrations in the alveolus. Sequential insults do not affect the inhibition of apoptosis. In vitro, PMN from endotoxemic animals display impaired chemotaxis to MIP-2 and interleukin-8. This may result in an inadequate host defense that contributes to increased ICU-acquired pneumonia in septic patients. 相似文献
22.
爆裂性骨折所致眼球内陷的CT研究 总被引:6,自引:0,他引:6
目的:研究眼眶爆裂性骨折后,眼球内陷与眼眶容积扩大的关系并对眼球内陷进行早期预报。方法:28例单侧眼眶爆裂性骨折后1~350 d患者,分别测量双侧眼球位置和骨性眼眶容积值,计算患侧眼球内陷值(E)和骨性眼眶容积扩大值(V),应用pearson积矩法研究E、V相关性并建立直线回归方程。结果:28例患侧E、V呈正相关(r=0.88,P<0.001);15例≤24 d的患者直线回归方程为E=0.85 V-1.74(r=0.86,P<0.001),13例>24 d的患者直线回归方程为E=0.86 V-0.60(r=0.9,P<0.001)。结论:眼球内陷值与眼眶容积扩大值高度相关;1 mL眼眶容积的扩大,可引起大约0.9mm(0.85~0.86 mm)的眼球内陷。与伤后>24 d的相比,≤24 d的眼球有明显的抗拒内陷的趋势,>24 d之后,这种趋势逐渐消失,随之发生眼球内陷。 相似文献
23.
Immunoreactive inhibin-like material (ILM) was measured by radioimmunoassay (RIA) in serum and gastric juice samples of 23 fasting normal men, 27 men with chronic superficial gastritis (CSG), and 21 men with carcinoma of stomach (5 for gastric analysis). Serum ILM levels in carcinoma of stomach patients (367 +/- 55.5 ng ml-1) were significantly higher than in normal men (15.4 +/- 2.6 ng ml-1; P less than 0.01) and in patients with CSG (109.8 +/- 17.7 ng ml-1; P less than 0.05). Sixty two per cent and 86% of patients with carcinoma of stomach showed elevated ILM levels which were higher than the highest noted in patients with CSG and normal men respectively. 相似文献
24.
目的 :分析多层螺旋CT扫描中使用高压注射器在不同增强剂量以及不同年龄组对肝脏动脉期和静脉期显影效果的影响。方法 :全部病例 (3 60例 )均使用MarconiMx 80 0 0多层螺旋CT和Medrad高压注射器。对比剂剂量按1.0ml/kg和 1.5ml/kg分为 2组行增强扫描 ,1.0ml/kg组 12 2例 ,1.5ml/kg组 2 3 8例 ;每组按照年龄分为 3组 ,18~ 3 9岁共 5 8例、40~ 5 9岁共 160例、60岁以上共 14 2例。结果 :分别测量各组肝脏双期增强CT图像上动脉期腹腔干和门脉期左右门静脉汇合处的CT值。对比分析发现两组对比剂量肝脏双期增强扫描效果均无明显差异 ,但青年组 (18~ 3 9岁 )与老年组 (>60岁 )比较发现门脉期有差异性。结论 :本文所选择对比剂剂量 1.0ml/kg是可行的 ,但是青年组行肝脏双期扫描时间需要提前。 相似文献
25.
目的 通过对深圳地区正常人群腰椎骨密度测量 ,获得本地区QCT骨密度正常参考值。方法 采用CT扫描机 ,羟磷灰石固体体模和QCT骨密度测量软件 ,选择了无骨质疏松疾病的正常人 1 0 2 8例 ,扫描第 3、第 4腰椎中层横断面 ,做QCT骨密度测量。对测量结果进行统计处理 ,得到男女人群骨峰值和年龄组均值。通过对年龄组数据进行不同标准的统计处理 ,探讨较为合理的诊断标准。通过不同的测量方法 (单纯松质和包括皮质 )的对比 ,探讨QCT与其他方法的差异。结果 根据 2 1~ 35岁年龄段统计出的骨峰值男性第 3腰椎为 1 65 85± 30 1 7,第 4腰椎为 1 70 95± 31 81。女性第 3腰椎为 1 75 33± 2 6 95 ,第 4腰椎为 1 81 97± 2 7 63。采用 4种不同的骨峰值降低标准统计骨质疏松症检出率 ,发现M 2 5 %组检出率偏高 ,M 30 %与M 2S较接近。包括皮质骨的测量降低敏感性。结论 进行深圳地区骨密度正常值调查 ,获得了男女人群骨峰值和年龄组均值 ,临床诊断建议采用骨峰值 30 %作为QCT测量诊断骨质疏松症的基本界限 相似文献
26.
目的 :评价螺旋CT中内插方式、螺距以及重建间隔对噪声的影响。方法 :采用SomatomPlus 4螺旋CT机。在相同条件下扫描直径为 2 0cm的水模 ,测得水模图像中心 40cm2 兴趣区的CT值标准差作为评价噪声水平的指标。结果 :3 60°线性内插的噪声减少 (t =3 4.87,P <0 .0 0 1) ,180°线性内插的噪声增加 (t =18.78,P <0 .0 0 1)。螺距大于 1.0或小于 1.0与螺距为 1.0时噪声水平的差异无显著性意义 (P >0 .0 5 )。随着重建间隔改变 ,相应噪声水平的差异无显著性意义 (P >0 .0 5 )。结论 :与常规扫描相比 ,螺旋CT内插方式对噪声有一定影响 ,而螺距与重建间隔对噪声水平影响不明显。 相似文献
27.
Purpose of Review
We provide an overview of our current understanding of combination lipid-lowering therapies intended for dyslipidemia treatment and cardiovascular disease prevention. First, we analyze recent statin and non-statin combination therapy guidelines and clinical studies since the publication of 2013 American College of Cardiology Cholesterol Guidelines. Second, we examine the clinical utility of non-statin agents alone and in combination in terms of LDL-C lowering and ASCVD risk reduction.Recent Findings
Medical societies, including the American College of Cardiology (ACC), National Lipid Association (NLA), and American Association of Clinical Endocrinologists (AACE), have released guidelines to address the appropriate use of non-statin therapies. The guidelines incorporated new evidence, including the IMPROVE-IT and FOURIER clinical trials, which demonstrate that the combination of statin therapy with other non-statin agents such as ezetimibe and PCSK9 inhibitors has a significant clinical benefit. Increasing evidence that aggressive low-density lipoprotein cholesterol (LDL-C) lowering leads to lower cardiovascular disease risk supports the need for continued exploration of the role of combination lipid-lowering therapies.Summary
A review of guidelines and clinical trials evaluating non-statin agents illuminates the growing base of evidence and expert opinion supporting the use of combination lipid-lowering therapies. While the majority of clinical trial data utilizes dyslipidemia monotherapy, especially statins, combination therapies represent an opportunity for individualized, patient-centered approach to LDL-C lowering and atherosclerotic cardiovascular disease (ASCVD) risk reduction. The overview provides a perspective on lipid management intended for clinicians who seek additional information and guidance on the use of combination therapies.28.
Concurrent use of intranasal and orally inhaled fluticasone propionate does not affect hypothalamic-pituitary-adrenal-axis function. 总被引:2,自引:0,他引:2
Ketan K Sheth Cindy K Cook Edward E Philpot Barbara A Prillaman Lori A Witham Melissa A Faris Kristofer C Klein Kathleen A Rickard 《Allergy and asthma proceedings》2004,25(2):115-120
Two double-blind, randomized, placebo-controlled, parallel group safety and efficacy studies included evaluation of the hypothalamic-pituitary-adrenal (HPA)-axis effects of concurrent treatment with intranasal and orally inhaled fluticasone propionate (FP). In the first study, patients with asthma who were > or =12 years of age were assigned randomly to receive twice-daily doses (either 88 or 220 microg) of orally inhaled FP delivered from a metered-dose inhaler (MDI). In the second study, patients were assigned randomly to receive either orally inhaled FP 250 microg or orally inhaled FP 250 microg/salmeterol 50 microg delivered via the Diskus device. In both studies, patients with rhinitis were allowed to continue the use of intranasal FP at their usual dosing. Treatment periods were 26 weeks and 12 weeks for the MDI and Diskus studies, respectively. HPA-axis effects were assessed using response to short cosyntropin stimulation testing. The number and percentage of patients with an abnormal cortisol response, defined as a morning plasma cortisol of <5 microg/dL, a poststimulation peak of <18 microg/dL, or a poststimulation rise of <7 microg/dL, were summarized in two subgroups: patients who used intranasal FP and those who did not. The concurrent administration of intranasal FP and orally inhaled FP via an MDI or Diskus or via Diskus with salmeterol was not associated with HPA-axis effects compared with orally inhaled FP alone. The results of these two studies suggest that concurrent use of intranasal FP with orally inhaled FP administered via MDI or Diskus for treatment of comorbid rhinitis and asthma does not increase the risk of HPA-axis abnormalities. 相似文献
29.