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991.
Gregory A Wellenius Gloria Y Yeh Brent A Coull Helen H Suh Russell S Phillips Murray A Mittleman 《Environmental health : a global access science source》2007,6(1):26
Background
Studies using administrative data report a positive association between ambient air pollution and the risk of hospitalization for congestive heart failure (HF). Circulating levels of B-type natriuretic peptide (BNP) are directly associated with cardiac hemodynamics and symptom severity in patients with HF and, therefore, serves as a marker of functional status. We tested the hypothesis that BNP levels would be positively associated with short-term changes in ambient pollution levels among 28 patients with chronic stable HF and impaired systolic function. 相似文献992.
Helen L Kelsall Malcolm R Sim Jillian F Ikin Andrew B Forbes Dean P McKenzie Deborah C Glass Peter Ittak 《BMC public health》2007,7(1):79
Background
Since the 1991 Gulf War concerns have been raised about the effects of deployment to the Gulf War on veterans' health. Studies of the reproductive health of Gulf War veterans have reported varied findings. 相似文献993.
Background
Mastitis is one of the most common problems experienced by women who are breastfeeding. Mastitis is an inflammation of breast tissue, which may or may not result from infection. The aims of this paper are to compare rates of mastitis in primiparous women receiving public hospital care (standard or birth centre) and care in a co-located private hospital, and to use multivariate analysis to explore other factors related to mastitis. 相似文献994.
David Gwyn Seymour John M. Starr Helen C. Fox Helen A. Lemmon Ian J. Deary Gordon J. Prescott Lawrence J. Whalley 《Quality of life research》2008,17(1):11-20
Background The direct-weighted Schedule for the Evaluation of Individual Quality of Life, Direct Weighting (SEIQoL-DW) is an individualised
measure of QoL that has been little used in very elderly people.
Methods We administered SEIQoL-DW during Wave 5 of the Aberdeen Birth Cohort 1921 Study (ABC1921) and sought statistical correlations
with other variables in the data set. ABC1921 participants had been IQ-tested in 1932 at age 11. Since 1997, data about cognition,
mental/physical function, personality, health, and socioeconomic status have been gathered in five waves of investigations.
Results Ninety-six out of 98 individuals, mean age 82.2, completed the SEIQoL-DW. Health, family, relationships, finances and social
pastimes were the commonest cues nominated, but age/gender differences existed. The mean SEIQoL-DW score (74.0) was significantly
lower than in an approximately 60% sample from Wave 3, the fall being greater in men. Variables statistically associated with
Wave 5 SEIQoL-DW usually reflected current rather than past status [including Short-Form 36 Health Survey (SF-36) components
and depression], although there were weaker correlations with years of education, housing in childhood, conscientiousness,
and IQ in 1998.
Conclusions SEIQoL-DW proved feasible and acceptable in community-dwelling octogenarians. Recent (i.e. statelike) rather than early or
long-standing (i.e. traitlike) influences appeared to have the greater effect on QoL. 相似文献
995.
Leslie F McCoy Peter F Scholl Anne E Sutcliffe Stephanie M Kieszak Carissa D Powers Helen S Rogers Yun Yun Gong John D Groopman Christopher P Wild Rosemary L Schleicher 《Cancer epidemiology, biomarkers & prevention》2008,17(7):1653-1657
Essential to the conduct of epidemiologic studies examining aflatoxin exposure and the risk of heptocellular carcinoma, impaired growth, and acute toxicity has been the development of quantitative biomarkers of exposure to aflatoxins, particularly aflatoxin B(1). In this study, identical serum sample sets were analyzed for aflatoxin-albumin adducts by ELISA, high-performance liquid chromatography (HPLC) with fluorescence detection (HPLC-f), and HPLC with isotope dilution mass spectrometry (IDMS). The human samples analyzed were from an acute aflatoxicosis outbreak in Kenya in 2004 (n = 102) and the measured values ranged from 0.018 to 67.0, nondetectable to 13.6, and 0.002 to 17.7 ng/mg albumin for the respective methods. The Deming regression slopes for the HPLC-f and ELISA concentrations as a function of the IDMS concentrations were 0.71 (r(2) = 0.95) and 3.3 (r(2) = 0.96), respectively. When the samples were classified as cases or controls, based on clinical diagnosis, all methods were predictive of outcome (P < 0.01). Further, to evaluate assay precision, duplicate samples were prepared at three levels by dilution of an exposed human sample and were analyzed on three separate days. Excluding one assay value by ELISA and one assay by HPLC-f, the overall relative SD were 8.7%, 10.5%, and 9.4% for IDMS, HPLC-f, and ELISA, respectively. IDMS was the most sensitive technique and HPLC-f was the least sensitive method. Overall, this study shows an excellent correlation between three independent methodologies conducted in different laboratories and supports the validation of these technologies for assessment of human exposure to this environmental toxin and carcinogen. 相似文献
996.
Buthionine sulfoximine sensitizes antihormone-resistant human breast cancer cells to estrogen-induced apoptosis
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Joan S Lewis-Wambi Helen R Kim Chris Wambi Roshani Patel Jennifer R Pyle Andres J Klein-Szanto V Craig Jordan 《Breast cancer research : BCR》2008,10(6):R104
Introduction
Estrogen deprivation using aromatase inhibitors is one of the standard treatments for postmenopausal women with estrogen receptor (ER)-positive breast cancer. However, one of the consequences of prolonged estrogen suppression is acquired drug resistance. Our group is interested in studying antihormone resistance and has previously reported the development of an estrogen deprived human breast cancer cell line, MCF-7:5C, which undergoes apoptosis in the presence of estradiol. In contrast, another estrogen deprived cell line, MCF-7:2A, appears to have elevated levels of glutathione (GSH) and is resistant to estradiol-induced apoptosis. In the present study, we evaluated whether buthionine sulfoximine (BSO), a potent inhibitor of glutathione (GSH) synthesis, is capable of sensitizing antihormone resistant MCF-7:2A cells to estradiol-induced apoptosis. 相似文献997.
998.
Diane L. Maennle Helen L. Grierson David G. Gnarra Dennis D. Weisenburger 《Fetal and pediatric pathology》1991,11(3):399-412
A detailed immunologic study of three cases of sinus histiocytosis with massive lymphadenopathy (SHML) was performed to better characterize this rare disorder. One patient had prominent cervical lymphadenopathy that regressed spontaneously, whereas the other two patients had persistent cervical lymphadenopathy and recurrent infections. The first patient was otherwise healthy and had normal immunologic studies. One of the latter patients had a relative increase in blood B cells, a decreased level of serum immunoglobulin A (IgA), decreased blood lymphocyte mitogenic responses to multiple mitogens (37-42% of controls), and cutaneous anergy. The other patient with persistent disease also had a relative increase in blood B cells, polyclonal hypergammaglobulinemia, and circulating immune complexes, as well as decreased blood T cells and markedly decreased blood lymphocyte responses to mitogens (12-37% of controls). Immunohistochemical stains of the lymph nodes of the three patients revealed a characteristic phenotype for the sinus histiocytes: S-100 protein, 3/3; CD14 (Leu M3), 3/3; CD11c (Leu M5), 1/1; CD71 (OKT9), 3/3; CD4 (Leu 3a), 2/3; CD1a (OKT6), 1/3; alpha-1-antitrypsin, 3/3; alpha-1-antichymotrypsin, 3/3; CD35 (C3b), 1/1; CD11b (Mo1), 0/3; CD15 (Leu M1), 0/3; HLA-DR, 0/3; and lysozyme, 0/3. This phenotype suggests that the cells of SHML have features of both the Langerhans/interdigitating cell and mononuclear phagocyte lineages. Emperipolesis by the histiocytes of B cells, T cells, and natural killer cells was demonstrated by a double-staining technique. Our findings indicate that patients with SHML may have a variably expressed immunodeficiency that predisposes them to recurrent infections. 相似文献
999.
1000.
Determination of the allelic frequencies of an L-myc and a p53 polymorphism in human lung cancer 总被引:5,自引:2,他引:5
Weston Ainsley; Ling-Cawley Helen M.; Caporaso Neil E.; Bowman Elise D.; Hoover Robert N.; Trump Benjamin F.; Harris Curtis C. 《Carcinogenesis》1994,15(4):583-587
The L-myc and p53 genes have been implicated in lung cancer.Both of these genes have restriction fragment length polymorphisms(RFLPs) that could account for differential expression or activityof variant forms. An EcoRI restriction site in the L-myc genewas previously reported to be a predictor of poor prognosisin Japanese lung cancer patients. There are several RFLPs inthe p53 gene. In exon 4 there is a polymorphism that codes foreither an arginine or proline residue at codon 72. We previouslyreported the frequency of DNA-RFLPs at these gene loci revealedby EcoRI and AccII respectively. Here we report results froma study comparing lung cancer cases (n = 31) with chronic obstructivepulmonary disease controls (n = 49). No association was foundbetween these RFLPs and disease status. Previous observationsthat the frequencies of these RFLPs varied by race were confirmed.The p53 arginine allele was found to be more common in Caucasians(0.71) than African Americans (0.50). The EcoRI restrictionsite present allele in L-myc was more frequent in African-Americans(0.71) than Caucasians (0.49). Thus, the allelic frequency forL-myc was similar in African Americans to that reported forJapanese, and the allelic frequency for p53 was similar in Caucasiansto that reported for Japanese. 相似文献