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941.
Bursian SJ Mitchell RR Yamini B Fitzgerald SD Murphy PA Fernandez G Rottinghaus GE Moran L Leefers K Choi I Fernadez G 《Veterinary and human toxicology》2004,46(3):122-129
The addition of nutritionally inert adsorbents to mycotoxin-contaminated animal feed has been a popular approach to decreasing toxicity in animals and carryover of mycotoxins from contaminated feed to animal by-products. Some studies suggest that esterified glucomannan derived from the cell wall of Saccharomyces cerevisiae is effective in reducing the bioavailability of at least some of the mycotoxins occurring in contaminated feed. Because cereal grains are important components of ranch mink diets, mycotoxicoses in mink is a potential problem faced by mink ranchers. We conducted a series of studies to determine if inclusion of a commercially available esterified glucomannan in ranch mink feed was effective in alleviating clinical signs indicative of exposure to ochratoxin A, fumonisin B1, moniliformin or zearalenone in adult mink. In 4 separate trials, mink were fed diets that contained 2.5, 5 or 10 mg ochratoxin A/kg feed, 200 mg fumonisin B1/kg feed, 20 mg moniliformin/kg feed, or 30 mg zearalenone/kg feed with or without 2 g esterified glucomannan/kg feed. Male mink fed diets containing ochratoxin A had significantly decreased feed intake as well as renal lesions characteristic of exposure to that mycotoxin. Inclusion of the esterified glucomannan did not ameliorate these effects. Male mink exposed to fumonisin B1 had increased urinary sphinganine concentration, which was not significantly reduced by the mycotoxin adsorbent. Male mink that consumed monilformin-contaminated diets had characteristic ultrastructural changes in the heart that were not reduced in severity by the esterified glucomannan. Female mink exposed to zearalenone had increased uterine weight, which was not reversed by inclusion of commercial mycotoxin binder in the contaminated feed. The results of this study suggest that a commercial esterified glucomannan was generally ineffective in alleviating effects indicative of exposure to ochratoxin A, fumonisin B1, monilformin and zearalenone in mink. 相似文献
942.
Atypical squamous cells of undetermined significance on cervical smears: follow-up study of an Asian screening population 总被引:2,自引:0,他引:2
BACKGROUND: The current study reports on the significance of cervical smears identified as atypical squamous cells of undetermined significance (ASCUS) in the largest Asian screening population to date. METHODS: From January 1998 to December 1999, 190,000 cervical smears were evaluated by the cervical cytology laboratory at the University of Hong Kong (Hong Kong, China). From these smears, 5579 ASCUS were identified. Follow-up cytology and histology findings were analyzed. RESULTS: Follow-up cytology or biopsy results were retrieved for 3601 women (64.5%). Of these, 544 (9.8%) and 96 women (1.7%) were found to have low-grade (LSIL) and high-grade (HSIL) squamous intraepithelial lesions, respectively. Biopsy results were obtained for 198 (36.4%) of the 544 women with LSIL. One hundred seventy-nine (32.9%) and 19 women (3.5%) were confirmed to have cervical intraepithelial neoplasia (CIN)-1 and CIN-2-CIN-3, respectively. Biopsy results were retrieved for 53 (55.2%) women with HSIL. Forty patients (41.7%) were confirmed to have CIN-2-CIN-3, whereas CIN-1 was found in the remaining patients. One woman with squamous cell carcinoma was diagnosed by colposcopic biopsy after immediate referral following a diagnosis of ASCUS. There was a significantly larger proportion of LSIL or HSIL (P < 0.0001) or higher-grade findings in women with ASCUS compared with the general screening population. Infective organisms were identified in 412 women (7.4%) with ASCUS. These women had a decreased risk of subsequent development of LSIL (P < 0.0001) or HSIL (P = 0.027). CONCLUSIONS: ASCUS smears indicated an increased risk of HSIL or carcinoma. The authors suggested careful patient follow-up in such cases. 相似文献
943.
Age, sexual behavior and human papillomavirus infection in oral cavity and oropharyngeal cancers 总被引:6,自引:0,他引:6
Smith EM Ritchie JM Summersgill KF Klussmann JP Lee JH Wang D Haugen TH Turek LP 《International journal of cancer. Journal international du cancer》2004,108(5):766-772
There are few well-established patient risk factors associated with human papillomavirus (HPV) infection in cancers of the oral cavity and oropharynx. The purpose of this study was to determine if there were significant different risk factors and tumor characteristics between HPV-positive and HPV-negative cancer cases. HPV was evaluated in cancer tissue and exfoliated oral cells of 193 oral cavity/oropharynx cancer patients using PCR and direct DNA sequencing. A patient questionnaire collected information about risk factors, sexual practices and medical history. The prevalence of HPV high-risk (HR) types was 20% in cancer cases. Three types were identified: HPV-16 (87%), HPV-18 (3%) and HPV-33 (11%). Risk factors for HPV-HR included younger age (< or = 55 years vs. > 55 years; adjusted OR = 3.4; 95% CI = 1.6-7.3) and younger-age cases who had more lifetime sex partners (adjusted OR = 3.8; 95% CI = 1.4-10.1), practiced oral-genital sex (adjusted OR = 4.3; 95% CI = 1.8-10.4) or oral-anal sex (adjusted OR = 19.5; 95% CI = 3.4-113). Compared to HPV-negative cancers, HPV-HR cancers were more likely to have a positive HPV-HR exfoliated oral cytology test (adjusted OR = 7.8; 95% CI = 3.4-18.4), later stage (adjusted OR = 3.0), nodal involvement (adjusted OR = 4.1) and advanced grade (adjusted OR = 3.0). This study shows new evidence that the prevalence of oncogenic mucosal HPV is higher in younger-age oral cavity/oropharynx cancer cases whose sexual practices are typically associated with sexual transmission of the virus. HPV detection also appears to be an indicator of advanced disease characteristics that may require different clinical treatment for this subset of patients. An exfoliated oral cytology test for HPV was a significant predictor of HR types in the cancers, suggesting that an oral rinse may provide an early biomarker of infected tumors. 相似文献
944.
945.
946.
Truong PT Olivotto IA Speers CH Wai ES Berthelet E Kader HA 《International journal of radiation oncology, biology, physics》2004,58(3):797-804
OBJECTIVE: Postoperative radiotherapy is frequently employed among breast cancer patients with positive surgical margins after mastectomy but there is little evidence to support this practice. This study examined relapse and survival among women with node-negative breast cancer and positive surgical margins after mastectomy. METHODS: Among 2570 women diagnosed between 1989 and 1998 and referred to the British Columbia Cancer Agency with pathologic (p)T1-2, pN0 invasive breast cancer treated with mastectomy, 94 had positive surgical margins and formed the study cohort. Women with more established indications for postmastectomy radiotherapy (PMRT) including T3-4 tumors or node-positive disease were excluded. Demographic, tumor, and treatment factors; relapse patterns; and Kaplan-Meier 8-year locoregional relapse-free, breast cancer-specific, and overall survival rates were compared between women who were treated with (n = 41) and without (n = 53) PMRT. RESULTS: Median follow-up time was 7.7 years. The distributions of age, histologic grade, lymphovascular invasion (LVI), estrogen receptor status, and number of axillary nodes removed were similar between the two treatment groups. Six local chest wall recurrences (6.4%), 4 regional recurrences (4.3%), and 11 distant recurrences (11.7%) were identified. Local relapse rates were 2.4% vs. 9.4% (p = 0.23), and regional relapse rates were 2.4% vs. 5.7% (p = 0.63), with and without PMRT, respectively. Trends for higher cumulative locoregional relapse (LRR) rates without PMRT were identified in the presence of age <==50 years (LRR 20% without vs. 0% with PMRT), T2 tumor size (19.2% vs. 6.9%), grade III disease (23.1% vs. 6.7%), and LVI (16.7% vs. 9.1%). Statistical significance was not demonstrated in these differences (p > 0.10), possibly because of the small number of events. In patients with age >50 years, T1 tumors, grade I/II disease, and absence of LVI, no locoregional relapse occurred even with positive margins. PMRT did not improve distant relapse, 8-year breast cancer-specific and overall survival rates. CONCLUSION: This study suggests that not all patients with node-negative breast cancer with positive margins after mastectomy require radiotherapy. Locoregional failure rates approximating 20% were observed in women with positive margins plus at least one of the following factors: age <==50 years, T2 tumor size, grade III histology, or LVI. The absolute and relative improvements in locoregional control with radiotherapy in these situations support the judicious, but not routine, use of PMRT for positive margins after mastectomy in patients with node-negative breast cancer. 相似文献
947.
Kearney D Byrne A Crean P Cox D Fitzgerald DJ 《Journal of the American College of Cardiology》2004,43(4):526-531
OBJECTIVES: We examined the contribution of cyclooxygenase (COX)-1 and -2 to the generation of prostacyclin, thromboxane (Tx) A(2), and 8-epi prostaglandin (PG) F(2alpha) during percutaneous transluminal coronary angioplasty (PTCA). BACKGROUND: Both TxA(2) and 8-epi PGF(2alpha) activate platelets and are mitogenic, whereas prostacyclin is a platelet inhibitor, and therefore may influence the outcome of PTCA. METHODS: Twenty-one patients undergoing PTCA while receiving aspirin 300 mg daily or aspirin plus the selective COX-2 inhibitor nimesulide were compared with 13 patients treated only with fradafiban, a glycoprotein IIb/IIIa antagonist. Urine was analyzed for the metabolites of TxA(2) (Tx-M) and prostacyclin (PGI-M) and for the isoprostane, 8-epi PGF(2alpha). RESULTS: In the fradafiban group, there was a marked increase in Tx-M during PTCA (mean, 1973; 95% confidence interval [CI] 112 to 3834 rising to mean 7645; 95% CI 2,009 to 13281 pg/mg creatinine, p = 0.018). The Tx-M excretion was similarly reduced by aspirin and the combination of aspirin and nimesulide. In contrast, the combination of nimesulide and aspirin inhibited PGI-M excretion to a greater extent than aspirin (p = 0.001). Urinary 8-epi PGF(2alpha) excretion was elevated following PTCA compared with normal subjects (p = 0.002) and appeared to be unaffected by any of the treatments. CONCLUSIONS: The increase in TxA(2) during PTCA is primarily COX-1 dependent, and aspirin alone is effective in suppressing its formation. In contrast, prostacyclin generation is both COX-1 and COX-2 dependent. The inhibition of COX-1 and COX-2 did not prevent the production of 8-epi PGF(2alpha), suggesting that this is not enzymatically derived. The persistent generation of 8-epi PGF(2alpha) may contribute to the thrombosis and restenosis that complicate PTCA. 相似文献
948.
The HeartMate VE Left Ventricular Assist Device (vented electric abdominally positioned pulsatile blood pump; Thoratec Corp., Pleasanton, CA), approved as a permanent support, or destination therapy, by the US Food and Drug Administration in 2002 and Medicare in 2003, is now a potential therapy for numerous patients. Postimplantation nursing care is crucial to the success of left ventricular support device therapy and long-term recipient outcome. Nurses also contribute to cost containment, making this a viable treatment for the facility and the patient. Consequently, nurses must be educated about left ventricular assist device concepts and challenges, the benefits of device placement, intensive care unit and postintensive care unit daily care requirements, and outpatient preparation. This knowledge will enable nurses to provide necessary care and to educate recipients, families, and community health care providers on how to give appropriate posthospital care. 相似文献
949.
OBJECTIVES: To identify patterns and predictors of antithrombotic use and to evaluate the appropriateness of antithrombotic therapy for stroke prophylaxis in institutionalized elderly patients with atrial fibrillation. DESIGN: Retrospective study. SETTING: Seventeen long-term care institutions in Edmonton, Alberta. SUBJECTS: Two hundred sixty-five long-term care residents, aged 65 and older, with atrial fibrillation. MEASUREMENTS: The proportion of patients who were prescribed warfarin, acetylsalicylic acid (ASA), both, or neither was determined. Odds ratios were calculated to identify risk factors for stroke and bleeding that are predictive of the receipt of anticoagulant therapy. Appropriateness of therapy was evaluated based on whether patients were prescribed antithrombotic therapy in accordance with their risk factors for stroke and bleeding. RESULTS: Warfarin was prescribed for 49% of patients, ASA for 22%, both for 8%, and neither for 20%. Nearly all patients (97%) were considered to be at high risk for stroke, with age being the predominant risk factor (88%>75), whereas about half were considered to be at low risk for bleeding. Multivariate analyses did not find any associations between individual risk factors for bleeding and anticoagulant treatment, with the exception of recent surgery (odds ratio=0.59, 95% confidence interval=0.37-0.94). Overall, 54.8% of patients received appropriate antithrombotic therapy. Of patients who were optimal candidates for anticoagulation, 60% received appropriate therapy (warfarin with or without ASA). CONCLUSION: Although warfarin was the most appropriate treatment in nearly all of this population at high risk for stroke, it was prescribed in fewer than two-thirds of patients. Antithrombotic therapy was not always prescribed in accordance with patients' risk factors for stroke and bleeding. There is a need for systematic identification of appropriate candidates for anticoagulation in the long-term care setting. 相似文献
950.