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991.
992.
Lilian Marcela Ferrer Rosina Cianelli Kathleen F. Norr Baltica Cabieses Alejandra Araya Lisette Irarrázabal Margarita Bernales 《Public health nursing (Boston, Mass.)》2009,26(5):440-448
ABSTRACT Objectives: In Chile, little information about the use of standard precautions (SP) among health care workers (HCWs) exists. As part of a larger study to tailor and test an HIV prevention intervention for community HCWs, this study describes the observed frequency with which appropriate SP were used by HCWs in low-income community clinics of Santiago. Also, the availability of supplies is described.
Sample: A total of 52 structured observations with potential contamination with body fluids were done.
Results: HCWs used SP inconsistently, especially neglecting hand washing, surface cleaning, and cleaning of shared materials. Lack of materials contributed in some instances of failure to use SPs, especially wiping surfaces and safe disposal of sharp instruments, as shown by a positive correlation between use of SP and availability of materials. Essential materials were usually available. Although more education should relate to a better understanding of the importance of SP, no difference was found between professionals and paraprofessionals in the use of SP.
Conclusions: It is clear that the initial training, continuing education, and ongoing support for practicing SP are not adequate. Training should be offered to HCWs involved in caring for clients at community clinics to stop the spread of HIV or other infectious diseases in health care settings. 相似文献
Sample: A total of 52 structured observations with potential contamination with body fluids were done.
Results: HCWs used SP inconsistently, especially neglecting hand washing, surface cleaning, and cleaning of shared materials. Lack of materials contributed in some instances of failure to use SPs, especially wiping surfaces and safe disposal of sharp instruments, as shown by a positive correlation between use of SP and availability of materials. Essential materials were usually available. Although more education should relate to a better understanding of the importance of SP, no difference was found between professionals and paraprofessionals in the use of SP.
Conclusions: It is clear that the initial training, continuing education, and ongoing support for practicing SP are not adequate. Training should be offered to HCWs involved in caring for clients at community clinics to stop the spread of HIV or other infectious diseases in health care settings. 相似文献
993.
994.
Qinghua Wu Ragnhild A Lothe Terje Ahlquist Ilvars Silins Claes G Tropé Francesca Micci Jahn M Nesland Zhenhe Suo Guro E Lind 《Molecular cancer》2007,6(1):45
Background
The epigenetics of ovarian carcinogenesis remains poorly described. We have in the present study investigated the promoter methylation status of 13 genes in primary ovarian carcinomas (n = 52) and their in vitro models (n = 4; ES-2, OV-90, OVCAR-3, and SKOV-3) by methylation-specific polymerase chain reaction (MSP). Direct bisulphite sequencing analysis was used to confirm the methylation status of individual genes. The MSP results were compared with clinico- pathological features. 相似文献995.
996.
997.
Monica E Loghin Michael D Prados Patrick Wen Larry Junck Frank Lieberman Howard Fine Karen L Fink Minesh Metha John Kuhn Kathleen Lamborn Susan M Chang Timothy Cloughesy Lisa M DeAngelis Ian H Robins Kenneth D Aldape W K Alfred Yung 《Clinical cancer research》2007,13(23):7133-7138
PURPOSE: To determine the maximum tolerated dose of irinotecan when administrated with temozolomide every 28 days, in patients with recurrent malignant glioma who were also receiving CYP450 enzyme-inducing antiepileptic drugs (EIAED), and to characterize the pharmacokinetics of irinotecan and its metabolites. The study was also intended to assess whether temozolomide affects the conversion of irinotecan to SN-38. DESIGN: Patients with recurrent malignant glioma received a fixed dose of temozolomide (150 mg/m(2)) daily for 5 days from days 1 to 5 every 28 days, and an i.v. infusion of irinotecan on days 1 and 15 of each cycle. The starting dose of irinotecan was 350 mg/m(2), which was escalated to 550 mg/m(2) in 50-mg/m(2) increments. The plasma pharmacokinetics of irinotecan and its active metabolite, SN-38, were determined during the infusion of irinotecan on cycle 1, day 1. RESULTS: Thirty-three patients were enrolled into the study and treated. Thirty-one patients were evaluable for both tumor response and toxicity and two patients were evaluable for toxicity only. Common toxicities included neutropenia and thrombocytopenia, nausea, vomiting, and diarrhea. Dose-limiting toxicities were grade 3 diarrhea and nausea/vomiting. The maximum tolerated dose for irinotecan was determined to be 500 mg/m(2). CONCLUSIONS: The recommended phase II dose of irinotecan in combination with temozolomide for patients receiving EIAEDs is 500 mg/m(2), administrated every 15 days on a 28-day schedule. This study also confirmed that concomitant administration of EIAEDs increases irinotecan clearance and influences SN-38 disposition. No pharmacokinetic interaction was observed between temozolomide and irinotecan. 相似文献
998.
Rachel M Layman Dafydd G Thomas Kent A Griffith Jeffrey B Smerage Mark A Helvie Marilyn A Roubidoux Kathleen M Diehl Lisa A Newman Michael S Sabel James A Hayman Lori J Pierce Daniel F Hayes Anne F Schott 《Clinical cancer research》2007,13(14):4092-4097
PURPOSE: Thymidine phosphorylase (TP) induction by docetaxel is a proposed mechanism for the observed preclinical synergy of docetaxel and capecitabine (DC). We evaluated whether TP protein expression is increased by docetaxel and correlates with pathologic complete response (pCR) in breast cancer patients. EXPERIMENTAL DESIGN: Women with stage II to III breast cancer were given four cycles of neoadjuvant docetaxel 36 mg/m(2) i.v. over 30 min on days 1, 8, and 15 and capecitabine 2,000 mg/d, in two divided doses, on days 5 to 21 of a 28-day cycle. Radiology-directed biopsies of the breast tumors were done at baseline and 5 days after the first dose of docetaxel to evaluate TP expression. Following DC therapy, patients had core breast biopsies, and if residual disease was present, received four cycles of standard dose-dense doxorubin and cyclophosphamide (AC). RESULTS: The pCR rate was 26.9% (95% confidence interval, 11.6-47.8). Up-regulation of TP expression was not observed by either quantitative immunofluorescence (QIF) or immunohistochemistry. Radiology-directed core biopsy after neoadjuvant chemotherapy accurately predicted pathologic response in 88% (95% confidence interval, 69.8-97.6) of the cases. Neither level of TP expression nor TP up-regulation correlated with pCR. Significant toxicity resulted in therapy discontinuation in 3 of 26 patients. CONCLUSIONS: DC chemotherapy exhibited a similar pCR rate compared with standard taxane regimens, with increased toxicity. TP expression was not up-regulated after docetaxel and did not correlate with therapeutic response. Core breast biopsy after neoadjuvant chemotherapy accurately predicted pathologic response. 相似文献
999.
Julie A Douglas Albert M Levin Kimberly A Zuhlke Anna M Ray Gregory R Johnson Ethan M Lange David P Wood Kathleen A Cooney 《Cancer epidemiology, biomarkers & prevention》2007,16(7):1510-1516
Rare inactivating mutations in the BRCA1 gene seem to play a limited role in prostate cancer. To our knowledge, however, no study has comprehensively assessed the role of other BRCA1 sequence variations (e.g., missense mutations) in prostate cancer. In a study of 817 men with and without prostate cancer from 323 familial and early-onset prostate cancer families, we used family-based association tests and conditional logistic regression to investigate the association between prostate cancer and single nucleotide polymorphisms (SNPs) tagging common haplotype variation in a 200-kb region surrounding (and including) the BRCA1 gene. We also used the Genotype-Identity-by-Descent Sharing Test to determine whether our most strongly associated SNP could account for prostate cancer linkage to chromosome 17q21 in a sample of 154 families from our previous genome-wide linkage study. The strongest evidence for prostate cancer association was for a glutamine-to-arginine substitution at codon 356 (Gln(356)Arg) in exon 11 of the BRCA1 gene. The minor (Arg) allele was preferentially transmitted to affected men (P = 0.005 for a dominant model), with an estimated odds ratio of 2.25 (95% confidence interval, 1.21-4.20). Notably, BRCA1 Gln(356)Arg is not in strong linkage disequilibrium with other BRCA1 coding SNPs or any known HapMap SNP on chromosome 17. In addition, Genotype-Identity-by-Descent Sharing Test results suggest that Gln(356)Arg accounts (in part) for our prior evidence of prostate cancer linkage to chromosome 17q21 (P = 0.022). Thus, we have identified a common, nonsynonymous substitution in the BRCA1 gene that is associated with and linked to prostate cancer. 相似文献
1000.
Number of nevi and early-life ambient UV exposure are associated with BRAF-mutant melanoma. 总被引:9,自引:0,他引:9
Nancy E Thomas Sharon N Edmiston Audrey Alexander Robert C Millikan Pamela A Groben Honglin Hao Dawn Tolbert Marianne Berwick Klaus Busam Colin B Begg Dianne Mattingly David W Ollila Chiu Kit Tse Amanda Hummer Julia Lee-Taylor Kathleen Conway 《Cancer epidemiology, biomarkers & prevention》2007,16(5):991-997
Malignant melanomas often contain BRAF or NRAS mutations, but the relationship of these mutations to ambient UV exposure in combination with phenotypic characteristics is unknown. In a population-based case series from North Carolina, 214 first primary invasive melanoma patients in the year 2000 were interviewed regarding their risk factors. Ambient solar UV exposures were estimated using residential histories and a satellite-based model. Cases were grouped on the basis of BRAF and NRAS somatic mutations, determined using single-strand conformation polymorphism analysis and radiolabeled DNA sequencing, and the risk profiles of these groups were compared. Mutually exclusive BRAF-mutant and NRAS-mutant cases occurred at frequencies of 43.0% and 13.6% with mean ages at diagnosis of 47.3 and 62.1 years, respectively. Tumors from patients with >14 back nevi were more likely to harbor either a BRAF mutation [age-adjusted odds ratio (OR), 3.2; 95% confidence interval (95% CI), 1.4-7.0] or an NRAS mutation (age-adjusted OR, 1.7; 95% CI, 0.6-4.8) compared with patients with 0 to 4 back nevi. However, BRAF-mutant and NRAS-mutant tumors were distinctive in that BRAF-mutant tumors were characteristic of patients with high early-life ambient UV exposure (adjusted OR, 2.6; 95% CI, 1.2-5.3). When ambient UV irradiance was analyzed by decadal age, high exposure at ages 0 to 20 years was associated with BRAF-mutant cases, whereas high exposure at ages 50 and 60 years was characteristic of NRAS-mutant cases. Our results suggest that although nevus propensity is important for the occurrence of both BRAF and NRAS-mutant melanomas, ambient UV irradiance influences risk differently based on the age of exposure. The association of BRAF mutations with early-life UV exposure provides evidence in support of childhood sun protection for melanoma prevention. 相似文献