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91.
Mary E Reid James R Marshall Denise Roe Michael Lebowitz David Alberts Achyut K Battacharyya Maria Elena Martinez 《Cancer epidemiology, biomarkers & prevention》2003,12(10):1006-1011
Colorectal adenomatous polyps are considered to be the precursor lesion of colorectal cancer (1-3). Greater understanding of the association between smoking and adenoma development enable better detection and prevention of colorectal cancer. This study was conducted in men and women, ages 40-80, participating in a randomized trial testing the effects of wheat bran fiber supplement on adenoma recurrence. First, we investigated smoking exposure (status, cigarettes/day, and years of smoking) and colorectal adenoma characteristics (location, histology, size, and multiplicity) at baseline colonoscopy (n = 1429). Second, we evaluated smoking exposure and adenoma recurrence (n = 1304). The prevalence of distal versus proximal adenomas was greater for < or =30 cigarettes/day [odds ratio (OR), 1.48; 95% CI, 1.02-2.16] and 15 to <25 years of smoking (OR, 1.95; 95% CI, 1.23-3.09) compared with never smokers. Tubular versus villous histology prevalence was increased for > or =30 cigarettes and > or =35 years of smoking (OR, 1.74; 95% CI, 1.21-2.49 and OR, 1.74; 95% CI, 1.24-2.45, respectively) compared with never-smokers. Years of smoking increased prevalence of multiple versus single adenomas, whereas cigarettes/day and years of smoking were associated with large adenomas (> or =1 cm) prevalence as compared with small lesions (< or =0.5 cm). Greater than 35 years of smoking was significantly associated with an increased risk of adenoma recurrence (OR, 1.42; 95% CI, 1.01-1.98). These results suggest that the association between smoking and adenoma prevalence varies by the characteristic of the lesion. Furthermore, the association between smoking and adenoma recurrence is modest and was only significant after a long duration of exposure. Additional investigations that characterize the genetic changes in specific subgroups of prevalent and recurrent adenomas associated with smoking exposure are needed. 相似文献
92.
Identification and validation of genes involved in the pathogenesis of colorectal cancer using cDNA microarrays and RNA interference. 总被引:47,自引:0,他引:47
Noelle Sevilir Williams Richard B Gaynor Shane Scoggin Udit Verma Tunc Gokaslan Clifford Simmang Jason Fleming Denise Tavana Eugene Frenkel Carlos Becerra 《Clinical cancer research》2003,9(3):931-946
PURPOSE: The purpose of this study was to profile gene expression changes in colorectal tumors to identify new targets and strategies for the management of this disease. EXPERIMENTAL DESIGN: cDNA microarray analysis was used to detect differences in gene expression between normal tissue and colon tumors and polyps isolated from 20 patients. To identify genes that are important in regulating the growth properties of colorectal cancer, RNA interference (RNAi) was used to disrupt expression of several of the overexpressed genes in a colon tumor cell line, HCT116, which showed similar patterns of gene expression as many of the patient tumors. RESULTS: Expression changes of > or =2-fold in approximately one-third of the patients were consistently observed for 2632 of a total of 9592 genes (574 up-regulated genes and 2058 down-regulated genes). Subsequent analysis of 13 genes by quantitative real-time PCR confirmed the reliability of this analysis. RNAi-mediated disruption of the expression of one of these genes, survivin, a potent inhibitor of apoptosis, severely reduced tumor growth both in vitro and in an in vivo xenograft model. CONCLUSIONS: The combined use of microarray analysis and RNAi provides an excellent system to define the role of specific genes that are up-regulated in cancer lead to the increased in vitro and in vivo growth of colon tumors. 相似文献
93.
Lauren E Abrey Craig H Moskowitz Warren P Mason Michael Crump Douglas Stewart Peter Forsyth Nina Paleologos Denise D Correa Nicole D Anderson Dawn Caron Andrew Zelenetz Stephen D Nimer Lisa M DeAngelis 《Journal of clinical oncology》2003,21(22):4151-4156
PURPOSE: To assess the safety and efficacy of intensive methotrexate-based chemotherapy followed by high-dose chemotherapy (HDT) with autologous stem-cell rescue in patients with newly diagnosed primary CNS lymphoma (PCNSL). PATIENTS AND METHODS: Twenty-eight patients received induction chemotherapy using high-dose systemic methotrexate (3.5 g/m2) and cytarabine (3 g/m2 daily for 2 days). Fourteen patients with chemosensitive disease evident on neuroimaging then received high-dose therapy using carmustine, etoposide, cytarabine, and melphalan with autologous stem-cell rescue. RESULTS: The objective response rate to the induction-phase chemotherapy was 57%, and median overall survival is not yet assessable, with a median follow-up time of 28 months. The overall median event-free survival time is 5.6 months for all patients and 9.3 months for 14 patients who underwent transplantation. Six of these 14 patients (43%) remained disease-free at last follow-up. Treatment was well tolerated; there was one transplantation-related death. Prospective neuropsychologic evaluations have revealed no evidence of treatment-related neurotoxicity. CONCLUSION: This treatment approach is feasible in patients with newly diagnosed PCNSL without evidence of significant related neurotoxicity. Although the transplantation results are similar to those achieved in patients with aggressive or poor-prognosis systemic lymphoma, the low response rate to induction chemotherapy and the significant number of patients who experienced relapse soon after HDT suggest that more aggressive induction chemotherapy may be warranted. 相似文献
94.
Weiss Robin A.; Whitby Denise; Talbot Simon; Kellam Paul; Boshoff Chris 《Journal of the National Cancer Institute. Monographs》1998,1998(23):51-54
Kaposi's sarcoma-associated herpesvirus or human herpesvirus
type8 (HHV-8) is present in all forms of Kaposi's sarcoma
(KS) aswell as in primary effusion lymphomas and some cases of
Castleman'sdisease. In KS tissues, HHV-8 is present in
endothelial andspindle cells. Current serologic tests suggest
that HHV-8 ispredominantly found in those at risk of KS and is
not as widespreadas most other human herpesviruses. HHV-8
encodes various proteinsthat may play a role in promotion of
cellular growth, includingcyclin- and G-coupled protein receptor
homologues, and anti-apoptoticproteins, including Bcl-2, IL-6
(i.e., interleukin 6), and FLIP(i.e., FLICE inhibitory protein)
homologues. In addition, HHV-8encodes two macrophage
inflammatory-like proteins with anti-humanimmunodeficiency virus
and angiogenic potential. 相似文献
95.
Linda Cardozo Professor Christopher Benness Consultant Denise Abbott Research Nurse 《BJOG : an international journal of obstetrics and gynaecology》1998,105(4):403-407
Objective To assess the efficacy of oral oestriol in the prevention of recurrent Urinary tract infections in elderly women.
Design Double-blind, randomised, parallel group, placebo controlled trial
Setting Urogynaecology Unit at King's College Hospital with some women recruited from the geriatric units of St. Pancras Hospital and Dulwich Hospital, London (UK).
Participants Seventy-two postmenopausal women older than 60 years of age (mean 73.2 years) suffering from recurrent urinary tract infections.
Intervention Oral oestriol (3 mg per day) or placebo for six months.
Main outcome measures Urinary tract infection rates.
Results The study was difficult to conduct because of its design and the age of the participants. Oral oestriol (3 mg per day) was not shown to be superior to placebo in the prevention of recurrent urinary tract infections, but both oestriol and placebo improved urinary symptoms during the trial.
Conclusion The power of the study might have been too low to detect a significant difference between the groups, or oral oestriol(3 mg per day) may have been either the wrong dose or the wrong route of administration for this indication. 相似文献
Design Double-blind, randomised, parallel group, placebo controlled trial
Setting Urogynaecology Unit at King's College Hospital with some women recruited from the geriatric units of St. Pancras Hospital and Dulwich Hospital, London (UK).
Participants Seventy-two postmenopausal women older than 60 years of age (mean 73.2 years) suffering from recurrent urinary tract infections.
Intervention Oral oestriol (3 mg per day) or placebo for six months.
Main outcome measures Urinary tract infection rates.
Results The study was difficult to conduct because of its design and the age of the participants. Oral oestriol (3 mg per day) was not shown to be superior to placebo in the prevention of recurrent urinary tract infections, but both oestriol and placebo improved urinary symptoms during the trial.
Conclusion The power of the study might have been too low to detect a significant difference between the groups, or oral oestriol(3 mg per day) may have been either the wrong dose or the wrong route of administration for this indication. 相似文献
96.
Bruce Simons-Morton Denise Haynie Keith Saylor Aria Davis Crump Rusan Chen 《Prevention science》2005,6(3):187-197
This study evaluated the effects of a school-based intervention on growth trajectories of smoking, drinking, and antisocial
behavior among early adolescents. Seven middle schools were randomized to intervention or comparison conditions and students
in two successive cohorts (n = 1484) provided five waves of data from sixth to ninth grade. The Going Places Program, included classroom curricula, parent
education, and school environment components. Latent growth curve analyses demonstrated significant treatment group effects,
including reducing increases in friends who smoke, outcome expectations for smoking, and smoking progression, but had non-significant
effects on drinking or antisocial behavior. The Going Places Program was effective in preventing increases in smoking progression,
but its efficacy as a more cross-cutting problem behavior preventive intervention was not confirmed. 相似文献
97.
Fernando Pretel Rute M Gon?alves-de-Andrade Fabio Carlos Magnoli Maria Esther R da Silva Jorge M C Ferreira Carmen W van den Berg Denise V Tambourgi 《Toxicon》2005,45(4):449-458
Loxosceles adelaida spiders (Araneae, Sicariidae) are found near and inside the caves in the Parque Estadual Turistico do Alto Ribeira (PETAR), Sao Paulo, Brazil, which are visited by thousands of tourists every year. Several Loxosceles species are a public health problem in many regions of the world, by causing severe dermonecrosis and/or complement dependent haemolysis upon envenomation. The aim of this study was to characterize the biochemical and biological properties of L. adelaida venom and evaluate the toxic potential of envenomation by this non-synanthropic Loxosceles species. The biological activities of the L. adelaida venom was compared to that of Loxosceles gaucho, a synanthropic species of medical importance in Brazil. L. adelaida venom showed a similar potential to induce haemolysis, dermonecrosis and lethality as L. gaucho venom. L. adelaida crude venom was purified, yielding a 31 kDa component endowed with haemolytic and dermonecrotic activities. In conclusion, we show here that the troglophile Loxosceles species, L. adelaida, commonly found in the complex of caves from PETAR, is potentially able to cause envenomation with the same gravity of those produced by synanthropic species. 相似文献
98.
Denise R Sokos 《American journal of health-system pharmacy》2005,62(4):367-377
PURPOSE: The role of the pharmacist in increasing pneumococcal and influenza vaccination rates and the clinical efficacy of pneumococcal and influenza vaccines are discussed. SUMMARY: Institutional pharmacists often play key roles on multidisciplinary committees and have the opportunity to make preventive therapies, such as vaccination, a priority. Standing-order programs authorize health care professionals to screen for vaccine eligibility and contraindications, administer vaccines, and monitor for adverse effects when following a physician- or institution-approved protocol. Current vaccination levels for the influenza and pneumococcal vaccines are suboptimal and well below the Healthy People 2010 goal of 90% of high-risk patients. Pharmacists should be familiar with the composition, immunogenicity, dosage, administration, efficacy, adverse reactions, contraindications, precautions, and cost-effectiveness of each vaccine, as well as with Advisory Committee on Immunization Practices recommendations and the supporting literature. CONCLUSION: Health-system pharmacists have the opportunity and responsibility to protect those at highest risk of pneumococcal disease and influenza through the use of standing-order vaccination programs. 相似文献
99.
Effects of hyaluronan on free-radical formation, corneal endothelium damage, and inflammation parameters after phacoemulsification in rabbits. 总被引:1,自引:0,他引:1
Giovanni Camillieri Annarita Nastasi Pietro Gulino Claudio Bucolo Filippo Drago 《Journal of ocular pharmacology and therapeutics》2004,20(2):151-157
Free-radical formation may play a role in postoperative complications of phacoemulsification (e.g., corneal endothelium damage from mechanical injury). The present experiments were aimed at investigating whether different molecular weight ranges (2000-2600, 2600-3200, or 3200-3800 kDa) of hyaluronan may influence free radical formation, corneal endothelium damage, and inflammation parameters after phacoemulsification in the rabbit eye. The viscoelastic substance was injected in the anterior chamber of rabbits' eyes before phacoemulsification, at a 2.5% concentration. The formation of free radicals was determined by adding luminol to the irrigation media and measuring the chemoluminescence in eyes. The corneal endothelial damage was evaluated by measuring the corneal central thickness by pachimetry. The inflammation parameters were measured by calculation in aqueous humor of peak levels of leukocytes and prostaglandin E(2) (PGE(2)) and evaluation in uveal tissue of myeloperoxidase activity. Hyaluronan decreased by about 58-60% free-radical formation during phacoemulsification, reduced by about 76-80% modifications in mean corneal thickness and by about 54-61% the corneal endothelial cell loss in all molecular weight ranges used. No difference was found among various molecular weight ranges. The highest molecular weight range showed to be more potent than the lowest range for reduced number of inflammation cells and level of PGE(2) in aqueous humor. Thus, hyaluronan reduces free-radical formation, exerts protection on the corneal endothelium and exerts anti-inflammation properties after phacoemulsification in rabbits. The latter effect seems to depend on the molecular weight of the substance. 相似文献
100.
Kimberly K. Engelman PhD ; Edward F. Ellerbeck MD MPH ; Denise Perpich MPH ; Niaman Nazir MBBS MPH ; Kevin McCarter PhD ; Jasjit S. Ahluwalia MD MPH 《The Journal of rural health》2004,20(1):36-42
CONTEXT: Breast cancer screening rates are lower in rural communities. Although studies have addressed barriers to mammography for rural residents, physician practice barriers have received less attention. PURPOSE: Controlled clinical trials have shown that the use of office reminder systems in primary care practices is related to increased clinical care rates. Therefore, we compared office systems use in primary care practices located in rural and urban communities and assessed the impact of these systems on rural-urban differences in mammography utilization. METHODS: We identified female Kansas Medicare beneficiaries aged 65 to 79 from Medicare claims data (N = 24,030) and determined which beneficiaries received a mammogram between April 1, 1999, and March 31, 2001. We linked beneficiaries to their primary care providers and obtained surveys from 180 primary care practices on their use of office reminder systems. FINDINGS: Mammography rates ranged from 20% to 92% (mean = 65%) among the 180 practices. Flowsheets with a mammography prompt were used by 33% of the practices, 38% utilized nonphysician staff to identify women due for mammograms, and 15% used computerized reminder systems. Urban practices used flowsheets more often than rural practices (44% versus 16%, P < 0.001). A multivariable regression model demonstrated higher mammography rates in urban practices, group practices, and practices using mammography flowsheets. CONCLUSIONS: Despite success in randomized controlled trials, reminder systems are not used often by primary care providers and are used even less often in rural compared to urban practices. Consistent implementation may be a major barrier to the successful adaptation of flowsheets by primary care offices. 相似文献