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61.
Walters MJ Paul-Clark MJ McMaster SK Ito K Adcock IM Mitchell JA 《Molecular pharmacology》2005,68(5):1343-1353
Smoking cigarettes is a major risk factor for the development of cardiovascular and respiratory disease. Moreover, smoking-induced pathophysiology is often resistant to the anti-inflammatory effects of glucocorticoids. The nature of cigarette smoke-induced inflammation is still not defined, although neutrophil recruitment and activation seem to be consistent features. In the current study, we have used a range of approaches to demonstrate that cigarette smoke activates human monocytes and macrophages to release the CXC chemokine CXCL8 [(interleukin-8 (IL-8)]. Furthermore, we show for the first time that cigarette smoke synergizes with proinflammatory cytokines IL-1beta and tumor necrosis factor-alpha, and it is this interaction that confers steroid resistance to smoke-induced CXCL8 release. We go on to show that smoke-induced activation of human cells is an oxidant-mediated phenomenon acting through activator protein-1, but not nuclear factor kappaB, pathway. These observations add significantly to our understanding of smoke as an inflammatory stimulus that has implications for potential the development of treatments of smoking or related disease. 相似文献
62.
Intravascular synovial sarcoma is a rare neoplasm that arises in large veins of the junctional zone between the proximal leg and lower trunk in adult women. Herein we report the first case of an intravascular synovial sarcoma of the external iliac vein. It was successfully treated with neoadjuvant radiotherapy, radical excisional surgery, and combined arterial and venous reconstruction. Intravascular synovial sarcoma should be considered in the differential diagnosis of any adult woman with deep venous thrombosis and a mass of the femoral or iliac venous system. 相似文献
63.
AIMS: To demonstrate the use of an internet-based retrospective diary to measure intoxication and to describe the epidemiology of intoxication in a university community. METHODS: A probability sample of 1564 New Zealand university students completed an Internet-based survey (82% response), including a retrospective diary in which the volume consumed on each of the preceding seven days and the duration of each episode were recorded, along with the respondent's gender, weight, and their typical quantity/frequency of consumption, as a measure of tolerance. These parameters were used to compute an estimated blood alcohol concentration (EBAC) for each episode. RESULTS: Using an EBAC of 0.08 g/100 ml as a criterion for intoxication produced lower estimates of incidence than binge drinking guidelines (>40 g for women, >60 g for men), or subjective reports. EBACs of 0.08 g per cent were exceeded at least weekly by 37% of women and 39% of men. Teenage females had higher EBACs than teenage males, despite lower consumption. Intoxication was positively associated with lower age, European or Maori ethnicity relative to Asian, Pacific, or other ethnicities, and with residential halls relative to other living arrangements. Faculty of study was inconsistently related to intoxication. Discussion: Frequent drinking to intoxication is normative behaviour in this population group. Of particular concern are intoxication levels in females aged 16-21 years and in males throughout their 20s. The web-based retrospective diary is a useful means of measuring intoxication by self-report. Where time permits it can be enhanced by specification of drinking locations and beverage-specific questions. 相似文献
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66.
Attentional control involves the factors, or cognitive parameters, that determine which environmental inputs receive attention and which do not. Cognitive studies of attentional control have highlighted two general classes of control parameters, bottom-up (data driven or exogenous) parameters and top-down (goal driven or endogenous) parameters. Which of these control parameters is affected following parietal-lobe damage? In parietal-damaged patients, it is possible that a disorder in one control parameter (e.g. goal driven) would appear as a disorder in another parameter (e.g. data driven). To investigate the control parameters that might be affected in parietal patients, we simulated neglect in normal participants by disrupting data-driven information processing. When half of a computer monitor was degraded by translucent tracing paper while normal participants performed a cued spatial attention task (Experiment 1), the normal participants showed a pattern of results similar to patients with unilateral parietal-lobe damage--the so-called "disengage deficit." This pattern of results replicated when neutral attentional cues were included in the experiment (Experiment 2). However, the disengage deficit was not simulated in normal participants with predictive central symbolic cues (Experiment 3) or predictive peripheral cues (Experiment 4). Because perceptual degradation influences data-driven attentional control parameters, we suggest that these control parameters may be disrupted following parietal-lobe damage. 相似文献
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68.
O'Keeffe ST 《Sleep medicine》2005,6(3):281-282
This report describes a patient with iron deficiency in bone marrow examination and iron-responsive restless legs syndrome (RLS), in whom serum ferritin levels were well above the conventional cutoff for considering iron deficiency. The predictive value of serum ferritin for iron deficiency in RLS depends on the cutoff employed, on the pre-test likelihood of iron deficiency and on coexisting inflammatory conditions. Bone marrow examination is helpful when ferritin levels are equivocal. 相似文献
69.
Context. Nutritional support has become a standard of care for hospitalized patients, but whether total parenteral nutrition (TPN) affects morbidity and mortality is unclear. Objective. To examine the relationship between TPN and complication and mortality rates in critically ill patients. Data Sources. Computerized search of published research on MEDLINE from 1980 to 1998, personal files, and review of relevant reference lists. Study Selection. We reviewed 210 titles, abstracts, and papers. Primary studies were included if they were randomized clinical trials of critically ill or surgical patients that evaluated the effect of TPN (compared with standard care) on complication and mortality rates. We excluded studies comparing TPN with enteral nutrition. Data Extraction. Relevant data were abstracted on the methodology and outcomes of primary studies. Data were abstracted in duplicate, independently. Data Synthesis. There were 26 randomized trials of 2211 patients comparing the use of TPN with standard care (usual oral diet plus intravenous dextrose) in surgical and critically ill patients. When the results of these trials were aggregated, TPN had no effect on mortality (risk ratio [RR], 1.03; 95% confidence interval [CI], 0.81-1.31). Patients who received TPN tended to have a lower complication rate, but this result was not statistically significant (RR, 0.84; 95% CI, 0.64-1.09). We examined several a priori hypotheses and found that studies including only malnourished patients were associated with lower complication rates but no difference in mortality when compared with studies of nonmalnourished patients. Studies published since 1989 and studies with a higher methods score showed no treatment effect, while studies published in 1988 or before and studies with a lower methods score demonstrated a significant treatment effect. Complication rates were lower in studies that did not use lipids; however, there was no difference in mortality rates between studies that did not use lipids and those studies that did. Studies limited to critically ill patients demonstrated a significant increase in complication and mortality rates compared with studies of surgical patients. Conclusions. Total parenteral nutrition does not influence the overall mortality rate of surgical or critically ill patients. It may reduce the complication rate, especially in malnourished patients, but study results are influenced by patient population, use of lipids, methodological quality, and year of publication. 相似文献
70.
Intra-anal intussusception was diagnosed in eight of 39 patients on evacuation proctography. Posteroanterior views revealed prolapse of the infolded rectum into the anal canal on straining in seven of eight patients, associated with splaying open of the anal canal and sudden distal movement of the fold during prolapse. Similar changes were seen in four of 31 patients in whom intussusception had not been diagnosed on lateral evacuation proctography. The pattern of the collapsed rectum was assessed for fold length, thickness, and angulation in relation to the midline of the rectum. Infoldings that prolapsed were closer to the anorectal junction on stress (mean 14.6 42.4 mm, p < 0.0001) showed greater change in height between rest and strain (28.8 14.6 mm, p < 0.05) and became more acutely angled during straining (41.9 5.3°, p < 0.01). Intra-anal intussusception may be missed in 33% (four of 12 patients) on routine evacuation proctography. Posteroanterior stress proctography is a simple supplementary examination to validate intussusception. 相似文献