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排序方式: 共有837条查询结果,搜索用时 15 毫秒
1.
Petri Koivunen Niko Rantala Kalevi Hyrynkangas Kalevi Jokinen Olli-Pekka Alho 《European archives of oto-rhino-laryngology》2002,259(10):543-546
A population-based survey was conducted in northern Finland in order to study the incidence rate and survival in patients with pharyngeal cancer diagnosed between 1986 to 1996. A total of 95 new patients with hypopharyngeal, oropharyngeal or nasopharyngeal cancers were identified. The overall age-adjusted incidence rates (per 100,000 years) were 1.28 in men and 0.60 in women, giving an overall incidence rate of 0.89. Most of the tumours were diagnosed at stage IV, and the median disease-specific survival times were 27.6 months for the patients with oropharyngeal cancer, 13.5 months for nasopharyngeal cancer and 17.7 for hypopharyngeal cancer. The most important factors that were associated with a poor prognosis were stage IV in oropharyngeal [Hazard ratio (HR) 3.68, 95% confidence interval (CI) 0.97-13.92] and hypopharyngeal cancer (HR 3.99, CI 1.51-10.67) and age over 65 years in nasopharyngeal cancer (HR 9.28, CI 1.79-47.99). 相似文献
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The NTP has a long history of using Fischer rats and has compiled a large database of incidences of lesions seen in control animals. Such a database is lacking for Harlan Sprague-Dawley (SD) rats. The intention of this paper is to report spontaneous lesions observed in female vehicle control Harlan SD rats, and to compare the incidence in 2 strains of rats (Fischer and Harlan SD) used in NTP studies. Female Harlan SD rats served as the test animals for a special series of 2-year studies. Male rats were not used in these studies. Complete histopathology was performed on all animals, and the pathology results underwent comprehensive NTP pathology peer review. The most commonly observed neoplasms in these female control Harlan SD rats were mammary gland fibroadenoma (71%), tumors of the pars distalis of the pituitary (41%) and thyroid gland C-cell tumors (30%). Female Fischer rats had incidences of 44% for mammary gland fibroadenomas, 34% for tumors of the pars distalis, and 16% for thyroid gland C-cell tumors. Fischer rats had a 15% incidence of clitoral gland tumors, while the Harlan SD rats had an incidence of < 1%. In contrast to Fischer F344 rats, the Harlan SD rats had a high incidence of squamous metaplasia of the uterus (44.2%). Squamous metaplasia is not a lesion commonly observed in NTP control Fischer rats. The Harlan SD rats had a very low incidence of mononuclear cell leukemia (0.5%), compared with an incidence of 24% in female Fischer rats. 相似文献
4.
Anne Jokinen Pekka Santtila Niklas Ravaja Sampsa Puttonen 《International journal of psychophysiology》2006,62(1):175-184
Guilty Knowledge Test measuring electrodermal reactions was carried out in order to investigate the quality of different questions and the validity of the test in a situation that resembled a true crime. Fifty participants were randomly assigned to commit one of two realistic mock crimes, and were later tested with GKTs concerning both the crime they had enacted and the one they had no knowledge of. Different scoring systems (SCRs and peak amplitudes as well as raw and standardised scores) were employed and compared when analyzing the results. Although there were some false positives, the test was able to differentiate between the groups of guilty and innocent participants. With the best scoring systems, the test was able to classify up to 84% of the innocent and up to 76% of the guilty correctly according to a logistic regression analysis. ROC areas reflecting these same results reached values above .80. Questions on matters that demanded the participants' attention and were easier to remember had better discriminative power. With nearly all scoring methods, there was a significant interaction between the salience of the relevant items and the guilt of the participants. Participants reacted more strongly to salient relevant items when they were guilty, while no different reactions were observed for the non-salient items between guilty and innocent participants. It is suggested that, although the Guilty Knowledge Test appears to be a valid measure of guilty knowledge even in crimes that are close to real crimes, the principles on which guilty knowledge test questions are constructed should be more clearly specified. 相似文献
5.
The anticonvulsant drug phenytoin, in less than cytotoxic concentrations, caused significant reductions in Ig secretion by unstimulated or EBV-stimulated normal MNC, as measured by PFC or secretion of Ig into the culture medium. Isotype-specific LBL varied in their sensitivity, the secretion of IgA (1 line) and IgG (3 lines) being reduced by phenytoin near therapeutic concentrations, whereas that of IgM (1 line) was resistant. Six-day exposure of MNC to phenytoin caused no selective depletion of or enrichment for B cells, monocytes or T cell subsets. The results suggest that the reduction in serum Ig levels reported in phenytoin-treated epileptic patients is, at least in part, due to a direct effect of the drug on the B lymphocyte. However, among EBV-activated normal MNC, those secreting IgA were no more sensitive to the drug than those secreting IgG or IgM, and other factors may, therefore, operate to cause the preferential reduction in serum IgA in phenytoin-treated patients. 相似文献
6.
Sallinen M Härmä M Mutanen P Ranta R Virkkala J Müller K 《Journal of sleep research》2003,12(2):103-112
Sleep in shift work has been studied extensively in regular shift systems but to a lesser degree in irregular shifts. Our main aim was to examine the sleep-wake rhythm in shift combinations ending with the night or the morning shift in two irregular shift systems. Three weeks' sleep/work shift diary data, collected from 126 randomly selected train drivers and 104 traffic controllers, were used in statistical analyses including a linear mixed model and a generalized linear model for repeated measurements. The results showed that the sleep-wake rhythm was significantly affected by the shift combinations. The main sleep period before the first night shift shortened by about 2 h when the morning shift immediately preceded the night shift as compared with the combination containing at least 36 h of free time before the night shift (reference combination). The main sleep period before the night shift was most curtailed between two night shifts, on average by 2.9 and 3.5 h among the drivers and the controllers, respectively, as compared with the reference combination. Afternoon napping increased when the morning or the day shift immediately preceded the night shift, the odds being 4.35-4.84 in comparison with the reference combination. The main sleep period before the morning shift became 0.5 h shorter when the evening shift preceded the morning shift in comparison with the sleep period after a free day. The risk for dozing off during the shift was associated only with the shift length, increasing by 17 and 35% for each working hour in the morning and the night shift, respectively. The results demonstrate advantageous and disadvantageous shift combinations in relation to sleep and make it possible to improve the ergonomy of irregular shift systems. 相似文献
7.
Expression of human pim family genes is selectively up-regulated by cytokines promoting T helper type 1, but not T helper type 2, cell differentiation 总被引:3,自引:0,他引:3
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Cytokines are the most important inducers of T helper (Th) cell differentiation. Interleukin-12 (IL-12) and interferon-alpha (IFN-alpha) are responsible for human Th1-cell differentiation, while IL-4 is the critical cytokine promoting Th2-cell development. These two subsets of cells co-ordinate immunological responses to pathogens as well as autoimmune or allergic reactions. The pim family of proto-oncogenes encodes serine/threonine-specific kinases involved in cytokine-mediated signalling pathways in haematopoietic cells. Here we demonstrate that expression of pim-1 and pim-2 mRNAs is selectively up- or down-regulated in human cord-blood-derived CD4+ cells freshly induced to polarize towards Th1 or Th2 cells, respectively, whereas their expression is inhibited in both cell types by the immunosuppressive transforming growth factor beta (TGF-beta). Moreover, the Th1-specific cytokines IL-12 and IFN-alpha, but not the Th2-specific cytokine IL-4, transiently up-regulate pim-1 and pim-2 mRNA expression in human peripheral blood T cells and natural killer cells. In addition, the Pim-1 protein levels are strongly up-regulated by Th1-specific cytokines in all of these cell types. Taken together, our results suggest that pim genes and their protein products are involved in the early differentiation process of T helper cells. 相似文献
8.
H Arvilommi K Poikonen I Jokinen O Muukkonen L R?s?nen J Foreman J K Huttunen 《Infection and immunity》1983,41(1):185-189
Earlier animal experiments have shown that selenium depletion may decrease immune functions. In this human study, 40 volunteers from a population with low serum selenium concentrations were supplemented with selenium or placebo for 11 weeks. Blood samples were drawn at intervals for analysis of selenium status and immune function. At the end of the supplementation period, plasma selenium levels were 74 ng/ml in the placebo group and 169 ng/ml in the supplemented group. The improvement in selenium status was associated with a 57% increase in the activity of platelet glutathione peroxidase in the group supplemented with selenium, but there was no increase in the activity of this enzyme in the placebo-treated subjects. Immune function was measured in vitro by tests of lymphocyte and granulocyte activity. Intracellular killing of Staphylococcus aureus by granulocytes was slightly lower in the placebo group than in the selenium group at the end of the supplementation period (77.2 compared to 85.2%; P less than 0.05). No significant changes were observed in phagocytosis, chemotactic factor generation, antibody or leukocyte migration inhibitory factor production by lymphocytes, or proliferative responses to phytohemagglutinin or concanavalin A. These results suggest that the selenium deficiency of the order found in Finland and some other areas of the world has little, if any, influence on the immune functions measured in this study. 相似文献
9.
H Lagstr?m R Sepp?nen E Jokinen T R?nnemaa M Salminen J Tuominen J Viikar O Simell 《European journal of clinical nutrition》1999,53(8):654-661
OBJECTIVE: To analyze food consumption, nutrient intakes and serum cholesterol concentrations of the parents in a child-targeted CHD intervention trial, during which the age of children increased from 7 months to 5 y. DESIGN AND SUBJECTS: The children were randomized to an intervention group (n = 540) or a control group (n = 522) at six months of age. The intervention families were counseled at 3-6 month intervals to reduce their child's intake of saturated fat and cholesterol. Dietary issues were discussed with the control families only briefly. The parents' food consumption was analyzed by 24 h dietary recall at the child's age of 7 and 13 months and at 2, 3, 4, and 5 y. Nutrient intakes were calculated using the Micro-Nutrica program. RESULTS: The mothers and fathers of the intervention children used less butter, more margarine and more skim milk than those of the control children (P < 0.001 for all measurements). After the onset of counseling, the intervention mothers consumed continuously less fat (1.4 E% less at the child's age of 5 y), less saturated fat (1.5 E% less at the child's age of 5 y) and more polyunsaturated fat (0.5 E% more at the child's age of 5 y) than the control mothers (P = 0.008, P < 0.001 and P < 0.001 for trend, respectively). After the child's age of 13 months the intervention fathers also had a continuously lower fat intake (2.4 E% less at the child's age of 5 y) and consumed less saturated fat (1.5 E% less at the child's age of 5 y) than the control fathers (P < 0.001 for trend for both measurements). The serum cholesterol concentration of the intervention mothers was consistently lower than that of the control mothers during the intervention (at child's age of 5 y 4.86 and 5.09 mmol/L, respectively; P for trend = 0.03), while the values of the intervention and control fathers showed no differences. CONCLUSIONS: Continuous dietary intervention begun in infancy and focused on modification of the child's diet according to the current principles of preventive cardiology, was accompanied by a moderate decrease in the intake of total and saturated fat in the parents, but serum cholesterol concentration diminished consistently only in the mothers of the intervention children. 相似文献
10.
The effect of erythromycin, fluvoxamine, and their combination on the pharmacokinetics of ropivacaine 总被引:2,自引:0,他引:2
We studied the effect of fluvoxamine and erythromycin on the pharmacokinetics of ropivacaine in a double-blinded, randomized, four-way cross-over study. Eight healthy volunteers ingested daily 1500 mg erythromycin for 6 days, 100 mg fluvoxamine for 5 days (Days 2-6), both erythromycin and fluvoxamine, or placebo. On Day 6, each subject received a single dose of 0.6 mg/kg ropivacaine IV over 30 min. Ropivacaine, 3-hydroxyropivacaine, and 2',6'-pipecoloxylidide in venous plasma and urine samples were measured for up to 12 h and 24 h, respectively. Fluvoxamine increased the area under the drug plasma concentration-time curve (AUC) of ropivacaine 3.7-fold (P: < 0.001), prolonged the elimination half-life (t(1/2)) from 2.3 to 7.4 h (P: < 0.01), and decreased the clearance by 77% (P: < 0.001). Erythromycin alone had only a minor effect on the pharmacokinetics of ropivacaine. However, when compared with fluvoxamine alone, the combination of fluvoxamine and erythromycin further increased the area under the drug plasma concentration-time curve and t(1/2) of ropivacaine by 50% (P: < 0.01). We conclude that inhibition of CYP1A2 by fluvoxamine considerably reduces elimination of ropivacaine. Concomitant use of fluvoxamine and CYP3A4 inhibitor erythromycin further increases plasma ropivacaine concentration by decreasing its clearance. Implications: Clinicians should be aware of the possibility of increased toxicity of ropivacaine when used together with inhibitors of CYP1A2. Concomitant use of CYP1A2 and CYP3A4 inhibitors further increases ropivacaine concentration. 相似文献