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91.
Idioms are an important aspect of language that comprises a sizeable portion of our vocabulary. However, lexical access research has largely been limited to understanding how literal words are accessed and processed in the mental lexicon. Adult data show that idioms are quickly accessed from the lexicon and are likely processed as long words [J. Verbal Learn. Verbal Behav. 18 (1979) 523]. The purpose of this study was to examine lexicalization of idioms in a group of school-aged children. Using a phrase classification design, this research tested the Lexical Representation Hypothesis [J. Verbal Learn. Verbal Behav. 18 (1979) 523] in 19 urban fifth graders (5 boys, 14 girls; M age=10.16 years). On a computer, the students classified 54 phrases, including 24 idioms (high, moderate, and low familiarity [J. Speech Hear. Res. 36 (1993) 728]), 24 grammatical control word strings and 6 unrelated foils as either idioms or nonidioms. The idioms were identified with 62% accuracy. Unexpectedly, the boys tended to show higher rates of accuracy than the girls. Response latencies were shorter on the idioms compared to the controls and high familiarity idioms were processed faster than moderate and low familiarity idioms. These findings provide developmental data for lexicalization of idioms and the relationship between lexicalization and familiarity. At the cocnlusion of this articel, the reader will be able to: (1). discuss the various theories of idiom access and processing, (2). discuss how lexical access relates to idiom knowledge in school-aged children, and (3). consider the association between lexical access and familiarity relative to idiom comprehension in school-aged children. 相似文献
92.
Djoussé L Folsom AR Province MA Hunt SC Ellison RC;National Heart Lung Blood Institute Family Heart Study 《The American journal of clinical nutrition》2003,77(4):819-825
BACKGROUND: Dietary intake of linolenic acid is associated with a lower risk of cardiovascular disease mortality. However, it is unknown whether linolenic acid is associated with a lower risk of carotid atherosclerosis. OBJECTIVE: The objective was to examine the association between dietary linolenic acid and the presence of atherosclerotic plaques and the intima-media thickness of the carotid arteries. DESIGN: In a cross-sectional design, we studied 1575 white participants of the National Heart, Lung, and Blood Institute Family Heart Study who were free of coronary artery disease, stroke, hypertension, and diabetes mellitus. High-resolution ultrasound was used to assess intima-media thickness and the presence of carotid plaques beginning 1 cm below to 1 cm above the carotid bulb. We used logistic regression and a generalized linear model for the analyses. RESULTS: From the lowest to the highest quartile of linolenic acid intake, the prevalence odds ratio (95% CI) of a carotid plaque was 1.0 (reference), 0.47 (0.30, 0.73), 0.38 (0.22, 0.66), and 0.49 (0.26, 0.94), respectively, in a model that adjusted for age, sex, energy intake, waist-to-hip ratio, education, field center, smoking, and the consumption of linoleic acid, saturated fat, fish, and vegetables. Linoleic acid, fish long-chain fatty acids, and fish consumption were not significantly related to carotid artery disease. Linolenic acid was inversely related to thickness of the internal and bifurcation segments of the carotid arteries but not to the common carotid artery. CONCLUSION: Higher consumption of total linolenic acid is associated with a lower prevalence odds of carotid plaques and with lesser thickness of segment-specific carotid intima-media thickness. 相似文献
93.
反义核酸对癌基因C-myc和N-ras蛋白表达的影响 总被引:1,自引:0,他引:1
目的为了研制新型的抗肝癌药物,观察了反义寡核苷酸对整合乙型肝炎病毒(HBV)的肝癌细胞基因治疗的作用.方法设计合成针对HBVPreS2基因翻译起始位点的反义寡核苷酸(ASON),并设非互补序列作对照,选择2.2.15细胞为细胞模型,ASON以10μmol/L浓度用药,用ELISA法观察了细胞培养上清液中HBsAg和HBeAg的变化,MTT法检测ASON对细胞的毒性作用,放射免疫方法检测细胞培养上清液中血清铁蛋白浓度.免疫细胞化学染色检测ASON对癌基因C-myc和N-ras蛋白表达的影响.结果ASON能有效地抑制HBV抗原表达,对HBsAg和HBeAg的抑制率分别为66%和91%.而ASON以20μmol/L或40μmol/L浓度用药4天对宿主细胞无毒性作用,ASON以10μmol/L浓度用药后第二天用药组和对照组血清铁蛋白浓度分别为(28.26士0.02)μg/L和(28.14土0.02)μg/L,两者相比差异无显著性(P>0.05).用药后第3天C-myc和N-ras蛋白表达降低,和对照组相比差异有显著性(P<0.05).结论该段反义寡核苷酸不仅抑制HBV抗原表达,而且抑制肝癌细胞的恶性表型而对宿主细胞无毒性,有可能成为有前途的抗肝细胞肝癌新药. 相似文献
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96.
Human monocytes express interleukin-2 receptor beta (IL-2R beta) constitutively; however, the function of these receptors has not been fully delineated. We discovered that IL-2R beta directs two biologic activities in human monocytes, the release of granulocyte-macrophage colony-stimulating factor (GM-CSF) and increased susceptibility to lysis by lymphokine-activated killer cells (LAK) cells. Human monocytes were purified from peripheral blood mononuclear cells by plastic adherence and anti-CD2 plus complement lysis. By a 5-hour 51Cr-release assay, monocytes cultured in IL-2 were found to gain increasing susceptibility to LAK cells with time and this effect was dose dependent. Maximal susceptibility was obtained with a 4-day culture in 1,000 U/mL of IL-2. Monocytes were also found to release GM-CSF in response to IL-2 using a CSF-dependent cell line, Mo7e. Because IL-2- induced GM-CSF release coincides with LAK lysis of IL-2-cultured monocytes, we treated monocytes with anti-GM-CSF and anti-IL-2R beta to determine whether GM-CSF release and LAK susceptibility were dependent or independent events. We found that both phenomena were inhibited by either antibody. Therefore, we conclude that IL-2-induced release of GM- CSF is mediated by IL-2R beta, which then acts to modulate the susceptibility of monocytes to lysis by LAK cells. 相似文献
97.
Hasegawa DK; Bennett AJ; Coccia PF; Ramsay NK; Nesbit ME; Krivit W; Edson JR 《Blood》1980,56(4):585-595
Factor V deficiency has been identified in 8 of 8 patients 7--20 yr of age, with Philadelphia-positive (Ph1+) chronic myelogenous leukemia (CML). In these 8 patients, factor V deficiency was not due to hepatic dysfunction, factor V inhibitors, or disseminated intravascular coagulation. In 3 patients, factor V activity rose 10%--12% (0.10--0.12 U/ml) after the infusion of 28--31 ml/kg body weight of fresh frozen plasma (FFP). The rise persisted less than 14 hr. The mean measured postinfusion rise in factor V was 18% of the expected rise calculated from the volume of FFP infused in the patients' plasma volume. In 4 patients, a small transient rise in factor V activity occurred after splenectomy or plateletpheresis. Factor V deficiency was completely corrected after a marked reduction in bone marrow cellularity in 2 patients with Ph1+ CML treated with extensive chemotherapy, total body irradiation, and bone marrow transplantation. Factor V deficiency was retrospectively observed in 6 of 20 patients, ages 20--80 yr, with Ph1+ CML and 3 of 6 patients with other myeloproliferative disorders. The factor V deficiency appears to be associated with the large myeloid- megakaryocytic cell mass characteristic of CML and other myeloproliferative disorders. 相似文献
98.
论血液质量管理与输血安全 总被引:3,自引:2,他引:3
李贺英 《中华医院管理杂志》1997,13(10):598-601
血液质量是当前输血管理工作中一项重要课题。近年来,由于外科手术和输血治疗的广泛开展,临床用血量逐年大幅度增大,达6%-8%,但是,随之而来的是一些经血传播疾病的发生,使输血管理工作面临严峻的形势。血液质量已成为广大医务工作者和社会各界普通关注的问题之一。 相似文献
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100.
Myeloma and the t(11;14)(q13;q32); evidence for a biologically defined unique subset of patients 总被引:10,自引:8,他引:10 下载免费PDF全文
Fonseca R Blood EA Oken MM Kyle RA Dewald GW Bailey RJ Van Wier SA Henderson KJ Hoyer JD Harrington D Kay NE Van Ness B Greipp PR 《Blood》2002,99(10):3735-3741
The t(11;14)(q13;q32) results in up-regulation of cyclin D1 and is the most common translocation detected in multiple myeloma, where it is also associated with a lymphoplasmacytic morphology. We performed an interphase fluorescent in situ hybridization (FISH) study to determine the clinical and biologic significance of the abnormality when testing a large cohort of myeloma patients. Bone marrow slides from multiple myeloma patients entered into the Eastern Cooperative Oncology Group phase III clinical trial E9486 and associated laboratory correlative study E9487 were analyzed using interphase FISH combined with immune-fluorescent (cytoplasmic immunoglobulin-FISH) detection of clonal plasma cells. We used FISH probes that hybridize to the 14q32 and 11q13 chromosomal loci. The t(11;14)(q13;q32) was correlated with known biologic and prognostic factors. Of 336 evaluable patients, 53 (16%) had abnormal FISH patterns compatible with the t(11;14)(q13;q32). These patients appeared to be more likely to have a serum monoclonal protein of less than 10 g/L (1 g/dL) (28% vs 15%, P =.029) and a lower plasma cell labeling index (P =.09). More strikingly, patients were less likely to be hyperdiploid by DNA content analysis (n = 251, 14% vs 62%, P <.001). Patients with the t(11;14)(q13;q32) appeared to have better survival and response to treatment, although this did not reach statistical significance. Multiple myeloma with the t(11;14)(q13;q32) is a unique subset of patients, not only characterized by cyclin D1 up-regulation and a lymphoplasmacytic morphology, but is also more frequently associated with small serum monoclonal proteins and is much less likely to be hyperdiploid. These patients do not have a worsened prognosis as previously thought. 相似文献