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排序方式: 共有5540条查询结果,搜索用时 15 毫秒
81.
Logan G Spector Yang Xie Leslie L Robison Nyla A Heerema Joanne M Hilden Beverly Lange Carolyn A Felix Stella M Davies Joanne Slavin John D Potter Cindy K Blair Gregory H Reaman Julie A Ross 《Cancer epidemiology, biomarkers & prevention》2005,14(3):651-655
BACKGROUND: The MLL 11q23 translocation arises in utero and is present in 75% of infant leukemias. That MLL+ acute myeloid leukemia (AML) can arise following chemotherapy with DNA topoisomerase II (DNAt2) inhibitors suggests that these substances, which also occur naturally in foods, may contribute toward infant leukemia. We hypothesized that maternal consumption of dietary DNAt2 inhibitors during pregnancy would increase the risk of infant leukemia, particularly AML(MLL+). METHODS: This Children's Oncology Group case-control study consisted of 240 incident cases of infant acute leukemia [AML and acute lymphoblastic leukemia (ALL)] diagnosed during 1996 to 2002 and 255 random digit dialed controls. Maternal diet during pregnancy was determined through a food frequency questionnaire. An index of specific foods identified a priori to contain DNAt2 inhibitors as well as vegetables and fruits were created and analyzed using unconditional logistic regression. RESULTS: There was little evidence of an association between the specific DNAt2 index and leukemia overall and by subtype. An exception was AML(MLL+); odds ratios (95% confidence intervals) comparing the second to fourth quartiles to the first were 1.9 (0.5-7.0), 2.1 (0.6-7.7), and 3.2 (0.9-11.9), respectively (P for trend = 0.10). For the vegetable and fruit index, there were significant or near-significant inverse linear trends for all leukemias combined, ALL(MLL+), and AML(MLL-). CONCLUSION: Overall, maternal consumption of fresh vegetables and fruits during pregnancy was associated with a decreased risk of infant leukemia, particularly MLL+. However, for AML(MLL+) cases, maternal consumption of specific DNAt2 inhibitors seemed to increase risk. Although based on small numbers, these data provide some support for distinct etiologic pathways in infant leukemia. 相似文献
82.
Favorable prognosis for patients 12 to 18 months of age with stage 4 nonamplified MYCN neuroblastoma: a Children's Cancer Group Study. 总被引:3,自引:0,他引:3
Mary Lou Schmidt Ashutosh Lal Robert C Seeger John M Maris Hiroyuki Shimada Maura O'Leary Robert B Gerbing Katherine K Matthay 《Journal of clinical oncology》2005,23(27):6474-6480
PURPOSE: The long-term survival of children between age 12 and 24 months with stage 4 neuroblastoma and nonamplified MYCN (MYCN-NA) has not been defined previously. PATIENTS AND METHODS: Survival for stage 4 MYCN-NA neuroblastoma patients enrolled onto Children's Cancer Group (CCG) protocols 321P2 (1986 to 1991) and 3891 (1991 to 1996) was analyzed. Treatment consisted of intensive alkylator-based induction chemotherapy with or without autologous bone marrow transplantation (ABMT) with or without 13 cis-retinoic acid. Survival was analyzed by age strata less than 12, 12 to 18, 18 to 24, and more than 24 months at diagnosis. Patients younger than 12 months were treated on the moderate-intensity CCG protocol 3881. RESULTS: Forty-three patients with stage 4 MYCN-NA disease enrolled onto CCG-321P2 (n = 17) or CCG-3891 (n = 26) were between 12 and 24 months of age at diagnosis. After a median follow-up of 94 months (range, 4 to 140 months), the 6-year event-free survival (EFS) for the 12- to 18-month age group was superior to that of the 18- to 24-month age group (74% +/- 8% v 31% +/- 12%; P = .008). The EFS for children older than 24 months with stage 4 MYCN-NA neuroblastoma was 23% +/- 3%, and for children younger than 12 months was 92% +/- 3%. CONCLUSION: Children diagnosed with stage 4 MYCN-NA neuroblastoma in the second year of life form a transitional group between infants and older children in terms of prognosis. Patients between 12 and 18 months of age have significantly better long-term survival than that of older children treated with intensive chemotherapy with or without ABMT. These patients may not benefit from additional intensification of therapy beyond that provided in earlier clinical trials and may even maintain this high survival rate with less intensive therapy. 相似文献
83.
BACKGROUND: Deep-vein thrombosis (DVT) and pulmonary embolism (PE) are the most important causes of morbility and mortality in patients submitted to surgical intervention: some peculiar factors of laparoscopic surgery can modify their risk. The aim of this study is to evaluate possible variations of the fibrinolytic system after cholecystectomy. METHODS: Eighteen patients affected by symptomatic and non-complicated gallstones have been included in this study. They were divided into two groups of nine patients each: the first group was submitted to laparoscopic cholecystectomy (LC) and the second to open cholecystectomy (OC). Antitrombin III (ATIII), fibrinogen degradation products (FDP), tissue plasminogen activator (tPA), and plasminogen activator inhibitor (PAI) have been evaluated preoperatively and 6, 12, 24 and 48 hours after the operation. RESULTS: The levels of ATIII did not present significantly variations. The FDP in both groups were significantly increased 48 hours after open cholecystectomy. Levels of PAI instead were increased in comparison to the basal values at 6, 12, 24, 48 hours with p < 0.05; p < 0.01 and p < 0.05 respectively in patients submitted to OC, in the LC group no variations were observed; a comparison between the groups showed a significant modification (p < 0.05) only at the 12th hour. CONCLUSIONS: The early mobilization of patients in the postoperative course and the lower invasion of LC can oppose the prothrombotic effect in the lower limbs. 相似文献
84.
Léa Rodrigues-Simioni Stella R Zamunér José C Cogo Caroline R Borja-Oliveira Júlia Prado-Franceschi Maria Alice da Cruz-H?fling Alexandre P Corrado 《Toxicon》2004,43(6):633-638
Whereas the presynaptic action of Crotalus durissus terrificus venom is well-established, Bothrops venoms have historically been considered to have only postsynaptic and muscular effects. However, some studies have also suggested a presynaptic action for these venoms. In this work, we used chick biventer cervicis preparations to compare the presynaptic actions of two Bothrops venoms (B. insularis and B. neuwiedi) with that of C. d. terrificus venom. At 10 microg/ml, all venoms produced irreversible blockade of the twitch tension responses, with no reduction in acetylcholine (ACh)-induced contractures and only a slight decrease in potassium induced-contractures. The times (in min) required to produce 50% neuromuscular blockade (C. d. terrificus: 16.3+/-0.7, n = 8; B. insularis: 30.0+/-1.9, n = 5; B. neuwiedi: 42.0+/-2.0, n = 8; mean +/- SEM) were significantly different among the venoms (p < 0.01). Lowering the temperature at which the experiments were done (from 37 to 24 degrees C) prevented neuromuscular blockade by the three venoms, indicating that enzyme activity may be involved in this response. At concentrations capable of causing complete neuromuscular blockade, creatine kinase release remained close to levels seen in control preparations incubated with Krebs solution alone (500-1200 IU/l). Commercial crotalic antivenom, but not bothropic antivenom, protected against the neuromuscular blockade caused by B. insularis and B. neuwiedi venoms. These observations indicate that bothropic venoms may contain components which act presynaptically in a manner similar to C. d. terrificus venom, and that at low venom concentrations a direct action on skeletal muscle does not contribute to this presynaptic neurotoxicity. 相似文献
85.
David Q Liu Bindhu V Karanam George A Doss Rick R Sidler Stella H Vincent Cornelis E C A Hop 《Drug metabolism and disposition》2004,32(9):1023-1031
The in vitro metabolism of MK-0767 [(+/-)-5-[(2,4-dioxothiazolidin-5-yl) methyl]-2-methoxy-N-[[(4-trifluoromethyl)-phenyl] methyl]benzamide], a novel 2,4-thiazolidinedione (TZD)-containing peroxisome proliferator-activated receptor alpha/gamma agonist, was studied in rat, dog, monkey, and human liver microsomes and hepatocytes, as well as in recombinant human CYP3A4-containing microsomes. Twenty-two metabolites (some at trace levels) were detected by liquid chromatography-tandem mass spectrometry analysis. All appeared to be phase I metabolites except for a glucuronide conjugate of a hydroxylated metabolite that was detected at trace levels. A constant neutral loss scan experiment performed on a triple quadrupole mass spectrometer proved to be very useful for resolving the metabolites from endogenous compounds. It was observed that the initial site of metabolism of MK-0767 was at the TZD ring leading to two major metabolites, namely the 5-hydroxy-TZD metabolite (M24) and the mercapto metabolite (M22). The latter was formed via the cleavage of the TZD ring with the elimination of the carbonyl adjacent to the sulfur atom. The structure of M24 was established by accurate mass measurements and NMR analysis. This hydroxy-TZD metabolite might represent an important precursor for a group of metabolites formed by TZD ring opening and subsequent loss of the sulfur moiety. The mercapto metabolite, on the other hand, is probably the key precursor for the TZD ring-opened metabolites with retention of the sulfur, even though the detailed mechanism of the ring scission remains to be characterized. From these studies, it was concluded that the TZD ring was the major site of metabolism of MK-0767. All the metabolites produced in vitro from human preparations were detected in the corresponding preparations from the nonclinical species. 相似文献
86.
Echocardiographic features of post−transcatheter aortic valve implantation thrombosis and endocarditis
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Marco Spartera MD Francesco Ancona MD Marta Barletta MD Isabella Rosa MD Stefano Stella MD Claudia Marini MD Leonardo Italia MD Matteo Montorfano MD Azeem Latib MD Ottavio Alfieri MD Alberto Margonato MD Antonio Colombo MD Eustachio Agricola MD 《Echocardiography (Mount Kisco, N.Y.)》2018,35(3):337-345
87.
Wanda Kwan Ulrike Tr?ger Dimitrios Davalos Austin Chou Jill Bouchard Ralph Andre Aaron Miller Andreas Weiss Flaviano Giorgini Christine Cheah Thomas M?ller Nephi Stella Katerina Akassoglou Sarah J. Tabrizi Paul J. Muchowski 《The Journal of clinical investigation》2012,122(12):4737-4747
In Huntington disease (HD), immune cells are activated before symptoms arise; however, it is unclear how the expression of mutant huntingtin (htt) compromises the normal functions of immune cells. Here we report that primary microglia from early postnatal HD mice were profoundly impaired in their migration to chemotactic stimuli, and expression of a mutant htt fragment in microglial cell lines was sufficient to reproduce these deficits. Microglia expressing mutant htt had a retarded response to a laser-induced brain injury in vivo. Leukocyte recruitment was defective upon induction of peritonitis in HD mice at early disease stages and was normalized upon genetic deletion of mutant htt in immune cells. Migration was also strongly impaired in peripheral immune cells from pre-manifest human HD patients. Defective actin remodeling in immune cells expressing mutant htt likely contributed to their migration deficit. Our results suggest that these functional changes may contribute to immune dysfunction and neurodegeneration in HD, and may have implications for other polyglutamine expansion diseases in which mutant proteins are ubiquitously expressed. 相似文献
88.
Anyfanti Panagiota Gavriilaki Eleni Pyrpasopoulou Athina Triantafyllou George Triantafyllou Areti Chatzimichailidou Sofia Gkaliagkousi Eugenia Aslanidis Spyros Douma Stella 《Clinical rheumatology》2016,35(5):1411-1411
Clinical Rheumatology - 相似文献
89.
Daniel R. Feikin M. Kariuki Njenga Godfrey Bigogo Barrack Aura Stella Gikunju Amanda Balish Mark A. Katz Dean Erdman Robert F. Breiman 《Clinical and Vaccine Immunology : CVI》2013,20(1):113-114
The role of serology in the setting of PCR-based diagnosis of acute respiratory infections (ARIs) is unclear. We found that acute- and convalescent-phase paired-sample serologic testing increased the diagnostic yield of naso/oropharyngeal swabs for influenza virus, respiratory syncytial virus (RSV), human metapneumovirus, adenovirus, and parainfluenza viruses beyond PCR by 0.4% to 10.7%. Although still limited for clinical use, serology, along with PCR, can maximize etiologic diagnosis in epidemiologic studies. 相似文献
90.
We examined the impact of acute noise stress on the feedback-related negativity (FRN) and whether this effect depended on stressor predictability. Participants performed a gambling task in a silence and a noise condition with either predictable or unpredictable noise. FRN amplitude was measured in three ways, either neglecting (mean amplitude) or correcting for overlap with other components (base-to-peak; mean amplitude minus average mean amplitude of surrounding peaks). Notably, results differed between measures. Valence and magnitude both affected the FRN. These effects were additive on the mean amplitude and base-to-peak measures, but interactive on the mean amplitude corrected for both peaks measure. Acute noise stress specifically modulated valence and magnitude effects on the FRN, although evidence differed between measures as to whether valence and/or magnitude were processed differently. These findings indicate that acute stress impairs cognitive control by the anterior cingulate cortex. Stressor predictability added little to the explanation of effects. 相似文献