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991.
Paul S. Nassif Steven Q. Simpson Angelo A. Izzo Pamela J. Nicklaus 《The Laryngoscope》1997,107(9):1223-1227
Interleukin-8 (IL-8), a potent neutrophilic chemoattractant and inflammatory cytokine, is present in middle ear effusions (MEEs) of children with otitis media and is thought to be responsible for the accumulation of neutrophils in MEEs. We hypothesized that IL-8 concentration predicts the total number and proportion of neutrophils in MEEs. IL-8 concentration and total and differential cell counts were measured in MEEs of children undergoing tympanostomy tube placement for otitis media. IL-8 was present in 80 (98%) of 82 effusions. The mean ± SEM value for IL-8 was 7342 ± 847 pg/mL. The mean ± SEM count and percentage of neutrophils were 1.34 × 106 ± 3.44 × 105 and 70.6 ± 3.1%, respectively. IL-8 concentrations correlated positively with the total number(r = +0.30; P = 0.02) and percentage of neutrophils(r= +0.32; P = 0.01) in the effusion. Additionally, purulent effusions had greater IL-8 concentrations (P = 0.003) and greater neutrophil count (P = 0.03) than mucoid or serous effusions. We conclude that IL-8 is consistently present in MEEs of children and IL-8 concentration predicts the total number and proportion of neutrophils. Furthermore, IL-8 concentration and the total number of neutrophils correlate positively with the type of effusion. These results support the hypothesis that IL-8 recruits neutrophils to the middle ear in MEEs. 相似文献
992.
肿瘤转移抑制基因nm23H1产物在人鼻咽癌中表达的研究 总被引:5,自引:0,他引:5
采用SP免疫组化技术,以NDPK/nm23H1特异的单克隆抗体为探针,对人鼻咽癌中nm23H1的表达及其与颈淋巴结转移的关系进行了研究。结果:31例鼻咽癌中nm23H1基因产物表达的阳性率为41.9%(13/31)。其中无转移组的阳性率为52.3%(11/21),有转移组的阳性率为20%(2/10),两组间具有显著性差异(P〈0.01),而在转移的颈淋巴结组织中nm23H1产物表达极微或无表达,其 相似文献
993.
5,10-Methylenetetrahydrofolate reductase gene variants and congenital anomalies: a HuGE review 总被引:26,自引:0,他引:26
The enzyme 5,10-methylenetetrahydrofolate reductase (MTHFR) is involved in folate metabolism. The MTHFR gene is located on chromosome 1 (1p36.3), and two common alleles, the C677T (thermolabile) allele and the A1298C allele, have been described. The population frequency of C677T homozygosity ranges from 1% or less among Blacks from Africa and the United States to 20% or more among Italians and US Hispanics. C677T homozygosity in infants is associated with a moderately increased risk for spina bifida (pooled odds ratio = 1.8; 95% confidence interval: 1.4, 2.2). Maternal C677T homozygosity also appears to be a moderate risk factor (pooled odds ratio = 2.0; 95% confidence interval: 1.5, 2.8). The A 1298C allele combined with the C677T allele also could be associated with an increased risk for spina bifida. Some data suggest that the risk for spina bifida associated with C677T homozygosity may depend on nutritional status (e.g., blood folate levels, intake of vitamins) or on the genotype of other folate-related genes (e.g., cystathionine-beta-synthase and methionine synthase reductase). Studies of the C677T allele in relation to oral clefts, Down syndrome, and fetal anticonvulsant syndrome either have yielded conflicting results or have not been yet replicated. 相似文献
994.
OBJECTIVE: To estimate the prevalence of overweight and obesity and weight changes over a 5-year period in a rural adult population by age group. SUBJECTS: Residents of Marinette County, Wis: 613 women and 352 men. METHODS: Age, body weight, and height data were collected during October and December 1997 in a volunteer convenience sample of white men and women (aged 20 to 74 years). Age groups in 10-year increments were defined by age in 1992. Weights obtained from medical and employment records from 1992 by medical personnel, as well as self-reported weights, were recorded for 1992 to assess weight changes from 1992 to 1997. RESULTS: In 1992 women and men had mean body weights of 72.1 and 88.4 kg, respectively. By 1997, the average weight for women in the same data set was 79.3 and that for men was 96.4 kg, a gain of 7.3 and 7.9 kg, respectively. For both women and men, those in the youngest age group (age 20 to 30 years) experienced the greatest 5-year increase in body weight: 11.0 and 12.1 kg, respectively; the next largest increase occurred in the second youngest group (age 30 to 40 years). The majority of the normal-weight subjects (58%, 229 of 393) moved into an overweight or obese category, the overweight and obese generally gained weight, and only 20 of 572 overweight or obese individuals moved from an unhealthful to a healthful body weight during the 5 years. APPLICATIONS/CONCLUSIONS: The data indicate a need for community-wide weight-gain prevention programs for young adult men and women in rural areas. Weight-reduction treatment programs should be geared toward older adults, as most have already attained an unhealthful weight, which is likely to increase. 相似文献
995.
996.
急性白血病患者血清微量元素谱分析 总被引:1,自引:0,他引:1
采用DCP-AES检测了40例急性白血病(初发18例,化疗后22例)血清中锌、铜、铁、硒、镍、钛等15种元素含量。结果显示:初发急性白血病患者血清锌、铁、硒、镍、钛均降低,铜、钙、镁、铜/锌比值均升高。化疗达CR后,血清锌、铜、铜/锌、硒均可正常,而化疗后NR组上述元素无改变。血清钙、镍、钛化疗后CR和NR组均无改善。表明微量元素与急性白血病转归相关。 相似文献
997.
Natalie A. Betz Heideh K Fattaey Brenda A. Westhoff Avelina Q. Paulsen Terry C. Johnson 《Breast cancer research and treatment》1997,42(2):137-148
Very few growth inhibitors have been identified whichcan inhibit the proliferation of a broad spectrumof human breast cancer cell lines. CeReS-18, anovel cell surface sialoglycopeptide growth inhibitor, can reversiblyinhibit the proliferation of both estrogen receptor positive(MCF-7) and negative (BT-20) human breast cancer celllines. In addition, at concentrations above those requiredfor the reversible inhibition of cell proliferation, CeReS-18can also induce cell death in MCF-7 cells.Changes in nuclear and cytoplasmic morphology, characteristic ofapoptosis, were detected in MCF-7 cells treated witha cytotoxic concentration of CeReS-18, and internucleosomal DNAcleavage was also observed. The sensitivity of MCF-7and BT-20 cells to the biological properties ofCeReS-18 could be influenced by altering the calciumconcentration in the extracellular growth medium, such thatwhen the calcium concentration in the environment wasdecreased, an increased sensitivity to CeReS-18-induced growth inhibitionand cytotoxicity were observed. The addition of thecalcium chelating agent EGTA to MCF-7 cells, culturedin a normal calcium environment, could mimic theincreased sensitivity to the biological effects of CeReS-18observed under reduced calcium conditions. 相似文献
998.
慢性鼻窦炎的定义及发病因素浅析 总被引:9,自引:1,他引:9
长期以来对于慢性鼻窦炎的定义一直缺乏统~认识,这阻碍了人们对其病因、病理生理学的深入研究。近年来,随着鼻科学及相关基础学科的发展,人们对慢性鼻窦炎的定义展开了广泛的讨论,同时认识到慢性易窦炎是多种因素相互影响、相互作用的结果,临床上针对这些环节进行综合治疗有助于提高疗效、减少复发。1慢性耳塞炎的定义定义慢性鼻窦炎的关键在于区分急性和慢性鼻窦炎。现代观点认为区别急性与慢性疾病应根据病理学表现而非严格的时间考虑[1],故一些学者将慢性鼻窦炎定义为粘膜存在明显的、持续的、不可逆的损伤、通过保守治疗难以解决… 相似文献
999.
目的:探讨补肾阴方左归饮和补肾阳方益肾宝对老年前期小鼠抗衰老的机制。方法:用14月龄雄性小白鼠为肾虚模型,观察左归饮及益肾宝对其肝、脑、肾、睾丸的细胞核体外RNA转录活性及无细胞提取液蛋白质合成活性的影响。结果:老年前期对照组小鼠4种脏器的细胞核体外RNA转录活性及无细胞提取液蛋白质合成活性明显低于青年组(3月龄)小鼠。经灌服左归饮和益肾宝2个月后,两给药组小鼠4种脏器的细胞核体外RNA转录活性及 相似文献
1000.
Hua Q 《Zhonghua yi shi za zhi (Beijing, China : 1980)》2000,30(1):19-20
清.赵学敏《本草纲目拾遗》卷七收载之金锁银开,分别为今铁线蕨科植物扇叶的线蕨AdiantumflabellulatumL.蓼科植物天荞麦FagopyrumcymosumMcisn。蓼科植物贯叶蓼PolygonumPerfoliaumL. 相似文献