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排序方式: 共有1460条查询结果,搜索用时 15 毫秒
991.
JA Sokoloski WF Hodnick ST Mayne C Cinquina CS Kim AC Sartorelli 《Canadian Metallurgical Quarterly》1997,11(9):1546-1553
Epidemiological studies have provided evidence that diets rich in antioxidant nutrients may reduce the risk of cancer. To evaluate the possibility that dietary phytochemicals with antioxidant potential would create an environment capable of affecting the differentiation of HL-60 leukemia cells, we measured the effects of vitamin E and other dietary antioxidants on the differentiation produced by low levels of vitamin D3 and analogs thereof. Vitamin E succinate and other antioxidant compounds (ie butylated hydroxyanisole, beta-carotene and lipoic acid) used alone had no significant effect on the differentiation of HL-60 cells; however, these agents markedly increased the differentiation produced by vitamin D3. Previous studies from this laboratory have shown that a sequence-specific antisense phosphorothioate oligonucleotide to the Rel A subunit of NF-kappaB enhanced the differentiation of HL-60 cells produced by several inducing agents. Consistent with these observations, vitamin E succinate caused a marked reduction in the nuclear content of NF-kappaB both in the presence and absence of vitamin D3. These findings suggest that NF-kappaB may be a factor in regulating the differentiation of myeloid leukemia cells. The results also indicate that combinations of vitamin D3 and analogs thereof with dietary antioxidants may be useful in overcoming the differentiation block present in acute promyelocytic leukemia cells. 相似文献
992.
993.
994.
WF McDaniel 《Canadian Metallurgical Quarterly》1997,53(5):485-489
The purpose of this study was to investigate the association of serum antibody levels to Streptococcus pneumoniae, Haemophilus influenzae and Moraxella (Branhamella) catarrhalis with age, gender and smoking in an elderly population. The study population comprised all the inhabitants aged 65 years or over in a rural municipality in south-western Finland. Serum samples were obtained from 1,174 out of a total of 1,360 subjects. Bacterial antibodies were measured by enzyme immunoassay (EIA) using pneumolysin and whole bacterial cells of H. influenzae and M. catarrhalis (mixture of 10 different strains for both) as antigens. The main findings were as follows: (i) antibody levels generally decreased with increasing age both in men and in women; (ii) antibody titres against H. influenzae and M. catarrhalis were higher in men than in women; and (iii) antibody titres to H. influenzae and M. catarrhalis, but not to S. pneumoniae, were significantly higher in smokers than in non-smokers. These data suggest that antibody-mediated protection against respiratory pathogens may be impaired in the elderly, leading to a higher susceptibility to respiratory tract infections, that the exposure to H. influenzae and M. catarrhalis may be higher in men than in women, and that smokers have more respiratory infections or colonization due to these 2 bacteria than do non-smokers. 相似文献
995.
J Péduzzi S Farzaneh A Reynaud M Barthélémy R Labia 《Canadian Metallurgical Quarterly》1997,1341(1):58-70
Recent follow-up studies have provided convincing evidence that the foundations of chronic airflow obstruction (CAO) are laid in utero and early childhood. Men born in Hertfordshire and Derbyshire, England, were more likely to have impaired lung function at 60-70 years of age if they had been lighter at birth and if they had had lower respiratory tract infection (LRTI) in the first 2 years of life. Furthermore, they were more likely to have died from chronic obstructive pulmonary disease if they had been lighter at 1 year of age. These findings suggest that impairment of pulmonary growth in utero and early childhood, as a consequence of undernutrition and LRTI, plays an important part in the development of CAO in late adult life. This may be of particular importance for the future respiratory health of developing nations as the additive effects of smoking take hold. 相似文献
996.
NT Levy WF Young TM Habermann JG Strickler JA Carney AW Stanson 《Canadian Metallurgical Quarterly》1997,72(9):818-822
OBJECTIVE: To analyze the clinical characteristics, laboratory features, and outcome in five patients who had biochemically proven adrenal insufficiency attributable to pathologically confirmed non-Hodgkin's lymphoma (NHL). MATERIAL AND METHODS: We retrospectively reviewed the medical records of all patients at Mayo Clinic Rochester during the period from 1976 to 1994 to identify those with both NHL, as listed in the surgical pathology tissue registry, and adrenal insufficiency. Histologically, the patients were classified on the basis of the working formulation and the revised European-American lymphoma classification. RESULTS: Three patients had diffuse large cell NHL, one patient had small noncleaved NHL, and one patient had cutaneous T-cell NHL. All five patients had stage IV disease. Adrenal insufficiency was confirmed by morning and evening determinations of serum cortisol levels and cosyntropin stimulation tests. All patients demonstrated loss of circadian rhythm. The median age of the patients was 77 years (range, 60 to 89). Three of the five patients died without treatment from 5 to 22 days after assessment. One patient died of a cerebrovascular accident. Despite initiation of chemotherapy, two patients died of progressive NHL at 7 weeks and 7 months. CONCLUSION: In our experience, biochemically proven adrenal insufficiency in patients with NHL is a manifestation of clinically advanced disease in elderly patients. A stepwise diagnostic approach is critical for the appropriate management of such patients. 相似文献
997.
The present studies were designed to evaluate the developmental toxicity of chlorpropham in mice. The first study was conducted to determine administration time, and the second study was designed to evaluate dose-response effects. Chlorpropham was administered to pregnant mice by gavage on Days 8, 8.3, 9, 9.3, 10, and 11 of gestation at a level of 3000 mg/kg bw, and the females were killed on Day 18 of gestation. The administration on Day 8.3 of gestation induced the highest percentage of external malformations with brachyury occurring among more litters than in other groups. Chlorpropham was administered to pregnant mice by gavage at a level of 0 (control), 750, 1500, and 3000 mg/kg bw on Day 8.3 of gestation, and the females were killed on Day 18 of gestation. The total resorption rate was significantly increased in the 3000 mg/kg bw group. The average fetal body weight of each sex was significantly reduced in the 3000 mg/kg treatment group. The total incidence of external malformations was significantly increased in the two highest dose groups in a dose-related manner. Again brachyury was significantly increased in the 3000 mg/kg bw group. 相似文献
998.
Magnetic resonance imaging (MRI) is a new medical imaging technique which has been used in evaluating ocular and orbital diseases in recent years. Owing to the high resolution of soft tissues and lesions, it is superior to ultrasound and computed tomography in the localization and characterization of an orbital tumor in diagnosis. In this paper, we analysed 80 cases of MR images of orbital tumors by which all the lesions were detected. Benign or malignant disorders were recognized in 59 cases and complete tumors with accurate localization were shown in 79 cases. The principles of MRI, signal intensity of various tumors and the indications of MRI were discussed. 相似文献
999.
CJ Hofmann SA Rensing MM H?uber WF Martin SB Müller J Couch GI McFadden GL Igloi UG Maier 《Canadian Metallurgical Quarterly》1994,243(5):600-604
Cryptomonads are unicellular algae with plastids surrounded by four membranes. Between the two pairs of membranes lies a periplastidal compartment that harbours a DNA-containing organelle, termed the nucleomorph. The nucleomorph is the vestigial nucleus of a phototrophic, eukaryotic endosymbiont. Subcloning of parts of one nucleomorph chromosome revealed a gene coding for an Hsp70 protein. We demonstrate the expression of this nucleomorph protein-coding gene and present a model for protein transport from the host to the endosymbiont compartment. 相似文献
1000.