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991.
992.
993.
FLT3-TKD mutation in childhood acute myeloid leukemia. 总被引:8,自引:0,他引:8
D-C Liang L-Y Shih I-J Hung C-P Yang S-H Chen T-H Jaing H-C Liu L-Y Wang W-H Chang 《Leukemia》2003,17(5):883-886
Mutations of receptor tyrosine kinases are implicated in the constitutive activation and development of human hematologic malignancies. An internal tandem duplication (ITD) of the juxtamembrane domain-coding sequence of the FLT3 gene (FLT3-ITD) is found in 20-25% of adult acute myeloid leukemia (AML) and at a lower frequency in childhood AML. FLT3-ITD is associated with leukocytosis and a poor prognosis, especially in patients with normal karyotype. Recently, there have been three reports on point mutations at codon 835 of the FLT3 gene (D835 mutations) in adult AML. These mutations are located in the activation loop of the second tyrosine kinase domain (TKD) of FLT3 (FLT3-TKD). The clinical and prognostic relevance of the TKD mutations is less clear. To the best of our knowledge, there has been no report to describe FLT3-TKD mutations in childhood AML. In this pediatric series, FLT3-TKD mutations occurred in three of 91 patients (3.3%), an incidence significantly lower than that of FLT3-ITD (14 of 91 patients, 15.4%) in the same cohort of patients. None of them had both FLT3-TKD and FLT3-ITD mutations. Sequence analysis showed one each of D835 Y, D835 V, and D835 H. Of the three patients carrying FLT3-TKD, two had AML-M3 with one each of L- and V-type PML-RARalpha, and another one had AML-M2 with AML1-ETO. None of our patients with FLT3-TKD had leukocytosis at diagnosis. At bone marrow relapse, one of the four patients examined acquired FLT3-ITD mutation and none gained FLT3-TKD mutation. 相似文献
994.
Peroxiredoxins in breast carcinoma. 总被引:11,自引:0,他引:11
Peeter Karihtala Anne M?ntyniemi Sang Won Kang Vuokko L Kinnula Ylermi Soini 《Clinical cancer research》2003,9(9):3418-3424
PURPOSE: Peroxiredoxins (Prxs) are a novel group of peroxidases containing high antioxidant efficiency and some of them having also effects on cell differentiation and apoptosis. The mammalian Prx family has six distinct members located in various subcellular locations, including peroxisomes and mitochondria, places where oxidative stress is most evident. EXPERIMENTAL DESIGN: We examined immunohistochemically a large set of samples from patients with breast carcinoma and investigated associations with parameters such as tumor-node-metastasis classification, hormone receptor status, and patient survival. Three biopsies of healthy breast tissue were used as controls. RESULTS: Expression of peroxiredoxins I, III, IV, and V was found in >or=80% of cases, whereas the expression of Prx II and VI was less frequent. Increased expression of Prx III was found to associate with the presence of progesterone (P = 0.02) and estrogen (P = 0.03) receptors, and Prxs IV (P = 0.009) and VI (P = 0.04) were overexpressed in progesterone receptor positive cases. Prx V was the only isoform that associated with items of tumor-node-metastasis classification, it was connected to a larger tumor size (P = 0.05) and positive lymph node status (P = 0.04). Prx V positivity was also connected with shorter survival (P = 0.04), whereas Prxs III (P = 0.002) and IV (P = 0.02) were related to better prognosis, probably resulting from their connection with a positive hormone receptor status. CONCLUSIONS: In conclusion, we found that expression of peroxiredoxins, especially III, IV and V, is increased in breast malignancy, suggesting the induction of Prxs as response to increased production of reactive oxygen species in carcinomatous tissue. 相似文献
995.
Darling RC Shah DM Chang BB Paty PS Kreienberg PB Lloyd WE Roddy SP 《Seminars in vascular surgery》2000,13(1):4-9
Carotid endarterectomy by the eversion technique allows for all of the benefits of conventional endarterectomy but obviates the need for a distal suture line on the smaller internal carotid artery, and thus batching. Carotid artery reanastomosis onto the bifurcation can be quickly and simply performed with almost no risk of closure-related restenosis, given the anastomosis is on the larger of 2 arteries. In our experience of over 3,000 eversion carotid artery endarterectomies, the restenosis rate has been less than 1% judged by rigorous duplex follow-up. In this article, the technique and utility of eversion carotid endarterectomy is discussed. 相似文献
996.
目的 评价放射性核素89锶 (89Sr)对骨转移癌的止痛疗效和不良反应 ,并探讨其在癌性骨痛治疗中的应用范围。方法 观察 35例骨转移癌患者使用89Sr治疗后的止痛疗效、肿瘤标记物水平的变化、不良反应及血液学毒副反应。结果 89Sr止痛总有效率为 71 .4 % ,其中来源于前列腺癌和乳腺癌的骨转移癌患者有效率达到 80 .0 %。少数肿瘤标记物水平有下降。副反应主要为轻度可逆性的骨髓造血功能损害。89Sr对血生化无明显不良影响。结论 89Sr是治疗骨转移癌疼痛的一种安全有效的方法 相似文献
997.
998.
999.
Assessment of a three-dimensional operating system with skill tests in a pelvic trainer 总被引:3,自引:0,他引:3
OBJECTIVES: To compare the performance of laparoscopic skill assisted by a traditional two-dimensional (2D) and a three-dimensional (3D) endoscopic video system in a pelvic trainer. MATERIALS AND METHODS: The 3D imaging system (DeepVision((R)), Automated Medical Products Corp.) consists of a traditional single lens optic laparoscope, a light source, an endoscopic camera (Stryker), a DeepVision processor and a DeepVision monitor. The 2D images could be obtained with the same system without turning on the DeepVision processor. Thirty-four medical personnel with no laparoscopic surgical experience were enrolled to perform two skill tests, the object-pick-up and spatial orientation test in a trainer box. They were randomly divided into two groups, one group performed the test under 2D conditions first and 3D later, and another group performed the test under 3D conditions first and 2D later. The duration needed to complete the skill tests was recorded and the differences on performance time under 2D and 3D conditions were calculated for each participant. Two-way ANOVA was used to analyze the statistic difference on the performance time in two conditions. RESULTS: The duration needed to complete the initial skill tests was similar among 2D and 3D conditions. For both tests, the average performance time decreased significantly for the second attempt regardless of 2D or 3D conditions. Statistic analysis disclosed significant difference for learning factor (p < 0.001 for object-pick-up test and p < 0.01 for spatial orientation test), but no significant difference between 2D and 3D conditions (p = 0.276 for object-pick-up test and p = 0.327 for spatial orientation test). CONCLUSION: A significant decrease of the performance time at the second attempt reflected the importance of a learning process in laparoscopic surgery. It appears that no significant benefits were obtained by this 3D operating system for surgeons without laparoscopic surgical experience. 相似文献
1000.
F. Huang P. Lee C. Lee L. Huang L. Chang S. Liu 《Archives of disease in childhood. Fetal and neonatal edition》1997,77(2):F135
AIM—To investigate the immunogenicity and safety of existing recommendations for hepatitis B vaccination in preterm infants.METHODS—Recombinant hepatitis B vaccine (H-B-VAX II, 5 µg per dose) was given to 85 preterm infants divided into two groups, using two different schedules. Forty four group A infants with birthweights of < 2000 g received three doses at 1, 2, and 7 months of age. Forty one group B infants with birthweights of ?2000 g received three doses at 0, 1, and 6 months of age.RESULTS—After vaccination, 42 infants from group A (95%) and 37 infants from group B (90%) developed protective levels of antibody. The final seropositive rate and the geometric mean concentration of hepatitis B surface antibody between the two groups were not significantly different. The immune response of preterm infants to hepatitis B vaccines was similar to that of term infants in a previous study.CONCLUSIONS—Preterm infants can be given hepatitis B vaccines using one of the above two different schedules, at a cutoff birthweight of 2000 g. 相似文献