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排序方式: 共有225条查询结果,搜索用时 15 毫秒
1.
Tonje Skuland Johan ØvrevikMarit Låg Per SchwarzeMagne Refsnes 《Toxicology and applied pharmacology》2014
Amorphous silica nanoparticles (SiNPs) have previously been shown to induce marked cytokine (interleukin-6; IL-6 and interleukin-8; CXCL8/IL-8) responses independently of particle uptake in human bronchial epithelial BEAS-2B cells. In this study the involvement of the mitogen-activated protein kinases (MAP-kinases), nuclear factor-kappa Β (NF-κΒ) and in particular tumour necrosis factor-α converting enzyme (TACE) and—epidermal growth factor receptor (EGFR) signalling pathways were examined in triggering of IL-6 and CXCL8 release after exposure to a 50 nm silica nanoparticle (Si50). Exposure to Si50 increased phosphorylation of NF-κΒ p65 and MAP-kinases p38 and JUN-N-terminal protein kinase pathways (JNK), but not extracellular signal regulated kinases (ERK). Inhibition of NF-κΒ and p38 reduced the cytokine responses to Si50, whereas neither JNK- nor ERK-inhibition exerted any significant effect on the responses to Si50. Increases in membrane-bound transforming growth factor-α (TGF-α) release and EGFR phosphorylation were also observed after Si50 exposure, and pre-treatment with inhibitors of these pathways reduced the release of IL-6 and CXCL8, but did not affect the Si50-induced phosphorylation of p38 and p65. In contrast, p38-inhibition partially reduced Si50-induced TGF-α release, while the p65-inhibition was without effect. Overall, our results indicate that Si50-induced IL-6 and CXCL8 responses in BEAS-2B cells were regulated through combined activation of several pathways, including NF-κΒ and p38/TACE/TGF-α/EGFR signalling. The study identifies critical, initial events in the triggering of pro-inflammatory responses by nanoparticles. 相似文献
2.
It has been proposed that an internal representation of body vertical has a prominent role in spatial orientation. This investigation investigated the ability of human subjects to accurately locate their longitudinal body axis (an imaginary straight body midline running from head to toes) while free-floating in microgravity. Subjects were tested in-flight, as well as on ground in normal gravity in both the upright and supine orientations to provide baseline measurements. The subjects wore a goggle device and were in total darkness. They used knobs to rotate two luminous lines until they were parallel to the subjective direction of their longitudinal body axis, in the roll (right/left) and the pitch (forward/backward) planes. Results showed that the error between the perceived and the objective direction of the longitudinal body axis was significantly larger in microgravity than in normal gravity. This error in this egocentric frame of reference is presumably due to the absence of somatosensory cues when free-floating. Mechanical pressure on the chest using an airbag reduced the error in perception of the longitudinal body axis in microgravity, thus improving spatial orientation. 相似文献
3.
Objective
Oral nonsteroidal antiinflammatory medications (NSAIDs) have been shown to reduce pain with first-trimester surgical abortion compared to placebo, but it is unclear if one NSAID is better than another. Some providers administer intramuscular ketorolac, though data regarding its efficacy in abortion are limited. This study was designed to compare oral ibuprofen to intramuscular ketorolac for pain management during first-trimester surgical abortion.Study Design
This was a randomized, double-blind, controlled trial. Women undergoing first-trimester surgical abortion with local anesthesia were randomized to preprocedural oral ibuprofen, 800 mg given 60–90 min preprocedure, or intramuscular ketorolac, 60 mg given 30–60 min preprocedure. The primary outcome was pain with uterine aspiration on a 21-point, 0–100, numerical rating scale. Secondary outcomes included pain with cervical dilation, postoperative pain and patient satisfaction.Results
Ninety-four women were enrolled; 47 were randomized to ibuprofen and 47 to ketorolac. The groups did not differ with regards to demographics, reproductive history or Depression Anxiety Stress Scale scores. Mean pain scores for suction curettage did not differ between groups (52.3 vs. 56.2, p=.53). There was also no difference in pain with cervical dilation (41.6 vs. 45.4, p=0.48) or postoperative pain (22.3 vs. 15.0 p=.076), though patients in the ketorolac group experienced significantly greater arm pain than those who received a placebo injection (30.4 vs. 15.6, p<.001). Satisfaction with pain control did not differ significantly by group.Conclusions
Intramuscular ketorolac does not offer superior pain control compared to oral ibuprofen for first-trimester surgical abortion.Implications
Intramuscular ketorolac does not offer superior pain control over oral ibuprofen during first-trimester surgical abortion, is more expensive and causes patients significant arm discomfort. Its use should therefore be reserved for patients who cannot tolerate oral NSAIDs. 相似文献4.
Tonje Anita Melum Anders P. Årnes Hein Stigum Audun Stubhaug Ólöf Anna Steingrímsdóttir Ellisiv B. Mathiesen Christopher S. Nielsen 《European Journal of Pain》2023,27(7):912-921
Background
Stroke lesions might alter pain processing and modulation by affecting the widely distributed network of brain regions involved. We aimed to compare pain tolerance in stroke survivors and stroke-free persons in the general population, with and without chronic pain.Methods
We included all participants of the sixth and seventh wave of the population-based Tromsø Study who had been tested with the cold pressor test (hand in cold water bath, 3°C, maximum time 106 s in the sixth wave and 120 s in the seventh) and who had information on previous stroke status and covariates. Data on stroke status were obtained from the Tromsø Study Cardiovascular Disease Register and the Norwegian Stroke Register. Cox regression models were fitted using stroke prior to study attendance as the independent variable, cold pressor endurance time as time variable and hand withdrawal from cold water as event. Statistical adjustments were made for age, sex, diabetes, hypertension, hyperlipidaemia, body mass index and smoking.Results
In total 21,837 participants were included, 311 of them with previous stroke. Stroke was associated with decreased cold pain tolerance time, with 28% increased hazard of hand withdrawal (hazard ratio [HR] 1.28, 95% CI 1.10–1.50). The effect was similar in participants with (HR 1.28, 95% CI 0.99–1.66) and without chronic pain (HR 1.29, 95% CI 1.04–1.59).Conclusions
Stroke survivors, with and without chronic pain, had lower cold pressor pain tolerance, with possible clinical implications for pain in this group.Significance
We found lower pain tolerance in participants with previous stroke compared to stroke-free participants of a large, population-based study. The association was present both in those with and without chronic pain. The results may warrant increased awareness by health professionals towards pain experienced by stroke patients in response to injuries, diseases and procedures. 相似文献5.
Oystein Tomte Kjetil Sunde Tonje Lorem Bjorn Auestad Chris Souders Jeff Jensen Lars Wik 《Resuscitation》2009,80(10):1152-1157
Aim of the studyClinical mechanical chest compression studies report diverging outcomes. Confounding effects of variability in hands-off fraction (HOF) and timing of necessary tasks during advanced life support (ALS) may contribute to this divergence. Study site variability in these factors coupled to randomization of cardiopulmonary resuscitation (CPR) method was studied during simulated cardiac arrest prior to a multicentre clinical trial.MethodAmbulance personnel from four sites were tested in randomized, simulated cardiac arrest scenarios with manual CPR or load-distributing band CPR (LDB-CPR) on manikins. Primary emphasis was on HOF and time spent before necessary predefined ALS task (ALS milestones). Results are presented as mean differences (confidence interval).ResultsAt the site with lowest HOF during manual CPR, HOF deteriorated with LDB-CPR by 0.06 (0.005, 0.118, p = 0.04), while it improved at the two sites with highest HOF during manual CPR by 0.07 (0.019, 0.112, p = 0.007) and 0.08 (0.004, 0.165, p = 0.042). Initial defibrillation was 29 (3, 55, p = 0.032) s delayed for LDB-CPR vs. manual CPR. Other ALS milestones trended toward earlier completion with LDB-CPR; only significant for intravenous access, mean difference 70 (24, 115, p = 0.003) s.ConclusionIn this manikin study, HOF for manual vs. mechanical chest compressions varied between sites. Study protocol implementation should be simulation tested before launching multicentre trials, to optimize performance and improve reliability and scientific interpretation. 相似文献
6.
Pancreatic alpha-cell function in trauma 总被引:7,自引:0,他引:7
7.
8.
Juel IS Solligård E Lyng O Strømholm T Tvedt KE Johnsen H Jynge P Saether OD Aadahl P Grønbech JE 《The Journal of surgical research》2004,117(2):283-295
BACKGROUND: The mucosal surface epithelium is an essential part of the functional intestinal barrier, but its structural response to ischemia/reperfusion is only partly characterized. The purpose of this study was to provide a detailed morphological evaluation of intestinal surface epithelium after aortic cross-clamping. MATERIAL AND METHODS: Pigs were subjected to thoracic aortic cross-clamping for 60 min and subsequent reperfusion for 120 min. Tissue blood flow and high-energy phosphates were measured with microspheres and HPLC, respectively. Urinary excretion of (14)C polyethylene glycol (MW 4000 Da) (PEG-4000), loaded into an intestinal loop, provided an index of intestinal permeability. RESULTS: Jejunal blood flow was restored at 10 min after aortic declamping. Denudation of the basement membrane of the intestinal villi tips, as a consequence of epithelial shedding, increased markedly during the initial 60 min of reperfusion (P = 0.002). During the following 45 min, the denuded basement membrane was partly covered with low cuboidal and squamous-shaped cells extending lamellipodia over a wavy basement membrane. Restoration of ATP at 60 min after aortic declamping correlated inversely to the extent of denuded basement membrane (r = 0.75, P = 0.032). Permeability of PEG-4000 increased markedly after aortic declamping and was linearly correlated to the area of denuded basement membrane (r = 0.87, P = 0.01). CONCLUSIONS: Reperfusion for 2 h after aortic cross-clamping is associated with initial aggravation of ischemia-induced injury in the porcine jejunum, but thereafter with restitution of the surface epithelium. Restoration of ATP may be important to avoid intestinal injury after ischemia. Increased permeability of a macromolecule in response to reperfusion is closely correlated to injury of the surface epithelium. 相似文献
9.
Kumle M Weiderpass E Braaten T Adami HO Lund E;Norwegian-Swedish Women's Lifestyle Health Cohort Study 《British journal of cancer》2004,90(7):1386-1391
The risk of ovarian epithelial neoplasia following use of hormonal contraceptives (HC) was examined in data from the Norwegian-Swedish Women's Lifestyle and Health cohort including 103551 women aged 30-49 years in 1991-92. Follow-up through 2000 produced 214 incident cases of histologically confirmed epithelial ovarian neoplasias (135 invasive and 79 borderline cases). Using the Cox proportional hazard models, ever having used HC was associated with a decreased relative risk of epithelial ovarian cancer of 0.6 (95% CI 0.5-0.8). The effect of duration of HC use was convincing (P for trend <0.0001), and more important than age at start of use or time since first or last use. There was no significant difference between the effects of combined oral contraceptives and progestins-only contraceptives on risk (P=0.98). Similarly, there was no significant difference between the effects of ever use of HC on invasive and borderline ovarian neoplasia (P=0.37). In this cohort, use of HC seems to reduce the risk of epithelial ovarian neoplasia markedly and persistently in relation to the duration of use. 相似文献
10.
Diffuse large B-cell lymphoma of bone: an analysis of differentiation-associated antigens with clinical correlation 总被引:6,自引:0,他引:6
de Leval L Braaten KM Ancukiewicz M Kiggundu E Delaney T Mankin HJ Harris NL 《The American journal of surgical pathology》2003,27(9):1269-1277
Twenty-nine patients with diffuse large B-cell lymphomas presenting with bone involvement, including 18 localized primary bone lymphomas (group 1), 2 multifocal primary bone lymphomas (group 2), and 9 patients with extraskeletal disease at diagnosis (group 3), were studied. The tumors were subclassified according to the criteria of the WHO classification and evaluated by immunohistochemistry for expression of antigens associated with germinal center (GC) and non-GC stages of B-cell differentiation (bcl-6, CD10, MUM-1, VS38c, CD138, bcl-2, and CD44). The presence of a BCL-2/IgH gene rearrangement was investigated by polymerase chain reaction. All cases were characterized by similar clinicopathologic and morphologic features and had similarly good overall outcome. The patients (23 males, 6 females, median age 44 years) had tumors in long bones (14), axial skeleton (8), limb girdles (3), and multiple sites (4). Most tumors (24) were centroblastic, with multilobated cells in 12 cases. Almost half of the tumors (14 of 29, 48%) were bcl-6+CD10+ (GC-like), 9 of 29 cases (31%) were bcl-6+CD10- (indeterminate phenotype), and 6 of 29 cases (21%) were CD10-bcl-6- (post-GC like). The indeterminate phenotype was seen only in primary bone lymphoma. MUM-1 was frequently expressed in GC-like and non-GC-like categories. We found no evidence of plasmacytic differentiation by CD138, and VS38c immunoreactivity was distinctly rare (2 of 29 cases). CD44 was detected in 6 tumors, all CD10-. Bcl-2 was expressed by 70% of the tumors, but only 1 of 23 cases tested had a Bcl-2/JH rearrangement by polymerase chain reaction. A survival analysis showed that GC-like tumors had a longer overall survival duration compared with non-GC-like tumors (P = 0.0046). In conclusion, a GC-like immunophenotype characterizes roughly half of large B-cell lymphomas of bone and is associated with an improved survival. 相似文献