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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
Wendy A G Stams Monique L den Boer H Berna Beverloo Jules P P Meijerink Elisabeth R van Wering Gritta E Janka-Schaub Rob Pieters 《Clinical cancer research》2005,11(8):2974-2980
PURPOSE: t(12;21)(p13; q22), present in approximately 25% of pediatric precursor B-ALL, is highly sensitivity to L-asparaginase and the prognosis depends on the intensity of the treatment protocol. This study analyzes the relationship between the mRNA expression of the genes and fusion products involved in t(12;21), in vitro sensitivity to prednisolone, vincristine, and L-asparaginase, and long-term clinical outcome in t(12;21)+ acute lymphoblastic leukemia (ALL) patients. EXPERIMENTAL DESIGN: Long-term clinical outcome in 45 t(12;21)+ ALL patients was related to mRNA expression of TEL, AML1, TEL-AML1, and AML1-TEL, determined by real-time quantitative PCR, and the in vitro sensitivity to prednisolone, vincristine, and L-asparaginase, using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assays. RESULTS: A significant approximately 3.5-fold lower TEL expression in t(12;21)+ compared with t(12;21)- ALL samples (P = 0.006) and normal controls (P = 0.004) was found. Expression of AML1 did not differ between t(12;21)+ and t(12;21)- ALL. However, AML1 expression in the leukemic cells was 2-fold higher compared with normal controls (P = 0.02). The TEL-AML1 fusion product was expressed in all t(12;21)+ cases, whereas the reciprocal fusion product AML1-TEL was expressed in only 76%. High expression levels of TEL-AML1 [hazard ratio (HR), 1.3; 95% confidence interval (95% CI), 1.10-1.57; P = 0.003], AML1-TEL (HR, 4.9; 95% CI, 1.99-12.40; P = 0.001) and AML1 (HR, 1.1; 95% CI, 1.03-1.22; P = 0.006) were associated with a poor long-term clinical outcome within t(12;21)+ ALL. Cellular drug resistance towards prednisolone, vincristine, and L-asparaginase could not explain this predictive value. Multivariate analysis including age and WBC showed that only high AML1-TEL expression is an independent poor prognostic factor in t(12;21)+ childhood ALL. CONCLUSION: High AML1-TEL expression is an independent poor prognostic factor in t(12;21)+ childhood ALL. 相似文献
92.
Eleftherios P Mamounas Ann Brown Stewart Anderson Roy Smith Thomas Julian Barbara Miller Harry D Bear Christopher B Caldwell Alonzo P Walker Wendy M Mikkelson Jay S Stauffer Andre Robidoux Heather Theoret Atilla Soran Atilla Sovan Bernard Fisher D Lawrence Wickerham Norman Wolmark 《Journal of clinical oncology》2005,23(12):2694-2702
PURPOSE: Experience with sentinel node biopsy (SNB) after neoadjuvant chemotherapy is limited. We examined the feasibility and accuracy of this procedure within a randomized trial in patients treated with neoadjuvant chemotherapy. PATIENTS AND METHODS: During the conduct of National Surgical Adjuvant Breast and Bowel Project trial B-27, several participating surgeons attempted SNB before the required axillary dissection in 428 patients. All underwent lymphatic mapping and an attempt to identify and remove a sentinel node. Lymphatic mapping was performed with radioactive colloid (14.7%), with lymphazurin blue dye alone (29.9%), or with both (54.7%). RESULTS: Success rate for the identification and removal of a sentinel node was 84.8%. Success rate increased significantly with the use of radioisotope (87.6% to 88.9%) versus with the use of lymphazurin alone (78.1%, P = .03). There were no significant differences in success rate according to clinical tumor size, clinical nodal status, age, or calendar year of random assignment. Of 343 patients who had SNB and axillary dissection, the sentinel nodes were positive in 125 patients and were the only positive nodes in 70 patients (56.0%). Of the 218 patients with negative sentinel nodes, nonsentinel nodes were positive in 15 (false-negative rate, 10.7%; 15 of 140 patients). There were no significant differences in false-negative rate according to clinical patient and tumor characteristics, method of lymphatic mapping, or breast tumor response to chemotherapy. CONCLUSION: These results are comparable to those obtained from multicenter studies evaluating SNB before systemic therapy and suggest that the sentinel node concept is applicable following neoadjuvant chemotherapy. 相似文献
93.
Wendy R Parulekar Andrew G Day Jon A Ottaway Lois E Shepherd Maureen E Trudeau Vivien Bramwell Mark Levine Kathleen I Pritchard 《Journal of clinical oncology》2005,23(25):6002-6008
PURPOSE: To investigate the therapeutic impact of chemotherapy-induced amenorrhea in premenopausal patients with breast cancer. PATIENTS AND METHODS: We conducted a retrospective cohort study of a National Cancer Institute of Canada Clinical Trials Group phase III trial involving premenopausal patients randomized to receive cyclophosphamide, methotrexate, and fluorouracil (CMF), versus intensive cyclophosphamide, epirubicin, and fluorouracil (CEF). The objectives of our study were to describe the incidence of amenorrhea at 6 and 12 months post-random assignment and to determine the association of amenorrhea with relapse-free and overall survival. RESULTS: Data on 442 patients were used in our analyses. Despite the higher cumulative dose of cyclophosphamide in the CMF treatment arm, at 6 months post-random assignment, the rate of amenorrhea was higher in the CEF group (relative risk, 1.2; 95% CI, 1.0 to 1.3), with no difference at 12 months. In the receptor-positive subgroup, 6-month amenorrhea rates were not associated with prognosis. In contrast, amenorrhea at 12 months was significantly associated with relapse-free survival (hazard ratio, 0.51; 95% CI, 0.32 to 0.82; P = .005) and overall survival (hazard ratio, 0.40; 95% CI, 0.22 to 0.72; P = .002). CONCLUSION: Late chemotherapy-induced amenorrhea seems to be associated with improved outcome in patients with premenopausal, receptor-positive breast cancer. 相似文献
94.
Associations between polymorphisms in the vitamin D receptor and breast cancer risk. 总被引:7,自引:0,他引:7
Wendy Y Chen Elizabeth R Bertone-Johnson David J Hunter Walter C Willett Susan E Hankinson 《Cancer epidemiology, biomarkers & prevention》2005,14(10):2335-2339
Biological and epidemiologic data suggest that vitamin D levels may influence breast cancer development. The vitamin D receptor (VDR) is a crucial mediator for the cellular effects of vitamin D and additionally interacts with other cell-signaling pathways that influence cancer development. Because functional data exist on FOK1 and previous studies have suggested a relation between BSM1 and breast cancer risk, we evaluated the associations of the FOK1 and BSM1 VDR polymorphisms and breast cancer risk. In a case-control study nested within the Nurses' Health Study, we genotyped 1,234 incident cases (diagnosed between return of a blood sample in 1989-1990 and June 1, 2000) and 1,676 controls for FOK1, and 1,180 cases and 1,547 controls for BSM1. We observed a significantly increased risk of breast cancer among carriers of the ff genotype of FOK1 (multivariate odds ratio, 1.34; 95% confidence intervals, 1.06-1.69) compared with those with FF. We did not observe an association between polymorphisms in BSM1 and breast cancer risk (multivariate odds ratio, 0.93; 95% confidence intervals, 0.72-1.20) for BB versus bb). The FOK1 association did not vary significantly by menopausal status, estrogen, and progesterone receptor status of the tumors, or plasma levels of 25 hydroxyvitamin D or 1,25 dihydroxyvitamin D. Our results suggest that the VDR may be a mediator of breast cancer risk and could represent a target for cancer prevention efforts. 相似文献
95.
96.
PURPOSE: To provide commentary and points of caution to consider before incorporating data mining as a routine component of any Pharmacovigilance program, and to stimulate further research aimed at better defining the predictive value of these new tools as well as their incremental value as an adjunct to traditional methods of post-marketing surveillance. METHODS/RESULTS: Commentary includes review of current data mining methodologies employed and their limitations, caveats to consider in the use of spontaneous reporting databases and caution against over-confidence in the results of data mining. CONCLUSIONS: Future research should focus on more clearly delineating the limitations of the various quantitative approaches as well as the incremental value that they bring to traditional methods of pharmacovigilance. 相似文献
97.
Autoantibodies to red blood cell antigens occur frequently with hemolysis among pediatric small bowel transplant recipients: Clinical implications and management 下载免费PDF全文
Reports have linked pediatric solid organ transplant recipients with the development of hemolytic autoimmune antibodies, especially in the setting of the immunosuppressant tacrolimus. This study aims to identify whether these observations also occurred at an institution that frequently performs pediatric multivisceral transplants and to characterize the treatment and outcome. Chart review was performed on all patients with RBC autoantibodies. Laboratory and clinical data were used to identify hemolysis. For transplant recipients with RBC autoantibodies, the type of transplant and outcome of the AIHA were profiled. One hundred twenty‐eight patients were identified with RBC autoantibodies, of which 22 patients were solid organ transplant recipients, including 18 SB graft recipients. Sixteen of the 18 had evidence of hemolysis. The incidence rate of AIHA in this population is estimated to be 10%, resulting in significant cost. Treatment included immunosuppressant modulation, steroids, IVIG, and plasma exchange, with 12 of the 16 patients responding. RBC autoantibodies occur in up to 10% in pediatric SB transplant recipients, with high cost of obtaining compatible blood. Neither tacrolimus nor receipts of a donor spleen were associated with the development of AIHA. Treatment using steroids and IVIG appears to be effective. 相似文献
98.
Anne C. Kirchhoff PhD MPH Courtney R. Lyles PhD Mark Fluchel MD Jennifer Wright MD Wendy Leisenring ScD 《Cancer》2012,118(23):5964-5972
BACKGROUND:
Health care outcomes for long‐term survivors of adolescent and young adult (AYA) cancer were compared with young adults without a cancer history, using the 2009 Behavioral Risk Factor Surveillance System data.METHODS:
Eligible participants were 20 to 39 years of age. There were N = 979 who self‐reported a cancer diagnosis between the ages of 15 to 34 years and were at least 5 years from diagnosis (excluding nonmelanoma skin cancer). The remaining 67,216 participants with no cancer history were used as controls. Using multivariable regressions, relative risks and 95% confidence intervals were generated to examine the relationship of survivor status on indicators of poor health care (uninsured, no personal health care provider, no routine care, and avoiding seeing a doctor due to cost). Adjusted proportions were calculated by demographic groups. Results are weighted by Behavioral Risk Factor Surveillance System survey design.RESULTS:
Although the proportion uninsured did not differ (21% of survivors vs 23% of controls), AYA survivors reported forgoing care due to cost at higher levels than controls (relative risk = 1.67, 95% CI = 1.44‐1.94). Cost barriers were particularly high for survivors aged 20 to 29 years (44% vs 16% of controls; P < .001) and female survivors (35% vs 18% of controls; P < .001). Survivors reporting poorer health had more cost barriers. Moreover, uninsured survivors tended to report lower use of health care than did controls.CONCLUSIONS:
AYA cancer survivors may forgo health care due to cost barriers, potentially inhibiting the early detection of late effects. Expanding health insurance coverage for young cancer survivors may be insufficient without adequate strategies to reduce their medical cost burdens. Cancer 2012. © 2012 American Cancer Society. 相似文献99.
PURPOSE OF REVIEW: Fetal growth restriction is a complicated perinatal condition, with multiple causes. It shares common pathophysiologies with other important disorders, such as preeclampsia and abruption. As a group, these conditions associated with ischemic placental disease are responsible for a large percentage of indicated preterm births. The ability to accurately predict, diagnose and manage these pregnancies has significant and far-reaching implications, including potential effects on long-term adult health. RECENT FINDINGS: Placental ischemia is the most common cause of fetal growth restriction. Alterations in placental development are being linked to various angiogenic mediators, which may be of future use in early risk-determination. Until then, the use of ultrasound to accurately diagnose fetal growth restriction and time delivery is the mainstay of management. Research in this area has revealed some commonalities in the deterioration of the growth restricted fetus, but has also indicated that not every affected fetus will follow the same progression in Doppler and other wellbeing parameters. Most importantly, gestational age at delivery is consistently being documented as a critical factor in perinatal morbidity and mortality. SUMMARY: Fetal growth restriction is a late manifestation of early abnormal placental development. Once abnormal Doppler velocimetry is present, surveillance and timing of delivery should be based on the antepartum test results and on the gestational age. 相似文献
100.