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101.
MM Hudson CA Poquette J Lee CA Greenwald A Shah X Luo EI Thompson JA Wilimas LE Kun WM Crist 《Canadian Metallurgical Quarterly》1998,16(11):3592-3600
PURPOSE: To determine the impact of treatment toxicity on long-term survival in pediatric Hodgkin's disease. PATIENTS AND METHODS: We studied late events in 387 patients treated for pediatric Hodgkin's disease on four consecutive clinical trials at St Jude Children's Research Hospital from 1968 to 1990. Relative risks, actuarial risks, and absolute excess risks for cause-specific deaths were calculated. RESULTS: As of April 1997, 316 (82%) of patients were alive, with a median follow-up of 15.1 (range, 2.9 to 28.6) years. In this cohort, which represented 5,623 person-years of follow-up, 71 fatal events resulted from Hodgkin's disease (n=36), second malignancies (n=14), infections (n=7), accidents (n=7), cardiac disease (n=6), and asphyxiation (n=1). The 5-year estimated event-free survival (EFS) for the entire cohort was 79.6%+/-2.1 %, which declined to 63.1%+/-4.4% by 20 years. Cumulative incidences of cause-specific deaths at 25 years were 9.8%+/-1.6% for Hodgkin's disease, 8.1%+/-2.6% for second malignancy, 4.0%+/-1.8% for cardiac disease, 3.9%+/-1.5% for infection, and 2.1%+/-0.8% for accidents. Standardized incidence ratios showed excess risk for all second malignancies (12; 95% confidence interval [CI], 8 to 17), acute myeloid leukemia (81; 95% CI, 16 to 237), solid tumors (11; 95% CI, 7 to 16), and breast cancer (33; 95% CI, 12 to 72). Standardized mortality ratios also showed excess mortality from cardiac disease (22; 95% CI, 8 to 48) and infection (18; 95% CI, 7 to 38). CONCLUSION: Compared with age- and sex-matched control populations, survivors of pediatric Hodgkin's disease who were treated before 1990 face an increased risk of early mortality related to second cancers, cardiac disease, and infection. 相似文献
102.
RR Bell MM Soliman VK Nonavinakere DM Hammerbeck JL Early 《Canadian Metallurgical Quarterly》1997,90(2-3):107-114
Ovalbumin-sensitized (50 mg/kg, i.p.) male Hartley-guinea-pigs (550-610 g; n = 6) were treated 14 days later intratracheally with saline, cadmium (Cd 0.3 mg), selenium (Se 0.3 mg or 0.06 mg) or Se (0.06 mg) with Cd (0.3 mg). After 24 h, baseline dynamic-lung-compliance (Cdynl) and pulmonary-resistance (Rp), and percent change after ovalbumin-aerosol-challenge (10 mg/ml, 60 s) were assessed. Cadmium or Se (0.3 mg), Se (0.06 mg) and/or Cd (0.3 mg) decreased Cdynl (P < 0.05). Selenium (0.3 mg) increased Rp (P < 0.05). Ovalbumin-challenge decreased Cdynl and increased Rp in all groups. Analysis of bronchoalveolar-lavage-fluid (BALF) displayed increased activities of lactate-dehydrogenase (LDH), beta-glucuronidase (beta-G), alkaline-phosphatase (AP), and protein due to 0.3 mg Se, 0.3 mg Cd alone or with 0.06 mg Se (P < 0.05). Findings indicated that, 0.3 mg Se is more detrimental than 0.3 mg Cd to lung-dynamics despite a modest protection by 0.06 mg Se against Cd illustrated by an ameliorated Cdynl and lower protein in BALF. 相似文献
103.
A. E. Saba A. E. El Sherif E. M. Elsayed 《JOM Journal of the Minerals, Metals and Materials Society》2007,59(10):53-57
Copper is usually present in concentrations less than 5 g/L−1 in dilute waste solutions. The low concentrations make these solutions unsuitable for the electro-flow owinning processes
via conventional electrolysis cells. Unconventional, two-and three-dimensional electrode cells with relatively large cathodic
area are essential for such treatment. Different types of cells are mentioned in the literature. Among these cells, the two-dimensional
Swiss-roll cell (SR) is considered in this study. The effects of cathodic current densities, initial copper concentrations,
free sulfuric acid concentration, the presence of iron and zinc cations, and the rate of flow of the solution on both the
cathodic current efficiency and power consumption were studied. Copper was removed from synthetic and industrial mixtures
of Cu/Fe/Zn sulfate solutions to less than 5 ppm with power consumptions of 10.326 kWh/kg−1 and 8.61 kWh/kg−1, respectively. The correlation between the SR cell and packed-column cell on such treatment was also considered. 相似文献
104.
Walid E. Elsayed Usama A. Ebead Kenneth W. Neale 《Canadian Metallurgical Quarterly》2009,13(3):198-207
The feasibility of strengthening concrete slabs in flexure, with and without cutouts, using the mechanically fastened (MF) FRP technique is investigated. Two series of large-scale reinforced concrete slabs are tested. The first series is comprised of five slabs without a cutout, and measuring 2,600×2,600×120?mm; the second series consists of four slabs of the same dimensions with a central cutout measuring 800×800?mm. The mechanically fastened system is found to be a valid alternative to the externally bonded system resulting in a rapid, economic, and effective strengthening technique for two-way concrete slabs. The increases in ultimate capacities of the MF FRP-strengthened slabs range between 30 and 70% over those of the unstrengthened specimens. In addition, finite-element modeling of MF FRP-strengthened slabs is introduced in this study. The interfacial behavior between the MF FRPs and the concrete substrate is accounted for by using appropriate interfacial models. Very good agreement is obtained between the test results and the numerical predictions. 相似文献
105.
Elsayed Kandyel 《Journal of Superconductivity》1999,12(2):403-408
The single-phased series of Sr-bearing Hg-1212 superconducting cuprate,(Hg0.7Mo0.3)Sr2(Sr1–x
La
x
)Cu2O
z
has been prepared. X-ray diffraction showed that, the obtained samples belong to the 1212-structure with tetragonal space group P4/mmm, similar to that of (Hg, Mo)Sr2(Ca, Y)Cu2Oz, and stabilized in a wide compositional range of 0.25x0.75. Refinements of the structure are carried out in which the oxygen atoms at the (Hg, Mo) layer is shifted from high-symmetry position (0.5, 0.5, 0) to (x, x, 0). Magnetization and electrical resistivity measurements show that the as-prepared samples exhibit evidence for superconductivity and their superconducting properties were improved after O2 annealing with T
onset
c
as high as 92 K. 相似文献
106.
HI McFarland AA Lobito MM Johnson JT Nyswaner JA Frank GR Palardy N Tresser CP Genain JP Mueller LA Matis MJ Lenardo 《Canadian Metallurgical Quarterly》1999,162(4):2384-2390
Definition of the immune process that causes demyelination in multiple sclerosis is essential to determine the feasibility of Ag-directed immunotherapy. Using the nonhuman primate, Callithrix jacchus jacchus (common marmoset), we show that immunization with myelin basic protein and proteolipid protein determinants results in clinical disease with significant demyelination. Demyelination was associated with spreading to myelin oligodendrocyte glycoprotein (MOG) determinants that generated anti-MOG serum Abs and Ig deposition in central nervous system white matter lesions. These data associate intermolecular "determinant spreading" with clinical autoimmune disease in primates and raise important issues for the pathogenesis and treatment of multiple sclerosis. 相似文献
107.
108.
DM Parry MM MacCollin MI Kaiser-Kupfer K Pulaski HS Nicholson M Bolesta R Eldridge JF Gusella 《Canadian Metallurgical Quarterly》1996,59(3):529-539
Neurofibromatosis 2 (NF2) features bilateral vestibular schwannomas, other benign neural tumors, and cataracts. Patients in some families develop many tumors at an early age and have rapid clinical progression, whereas in other families, patients may not have symptoms until much later and vestibular schwannomas may be the only tumors. The NF2 gene has been cloned from chromosome 22q; most identified germ-line mutations result in a truncated protein and severe NF2. To look for additional mutations and clinical correlations, we used SSCP analysis to screen DNA from 32 unrelated patients. We identified 20 different mutations in 21 patients (66%): 10 nonsense mutations, 2 frameshifts, 7 splice-site mutations, and 1 large in-frame deletion. Clinical information on 47 patients from the 21 families included ages at onset and at diagnosis, numbers of meningiomas, spinal and skin tumors, and presence of cataracts and retinal abnormalities. We compared clinical findings in patients with nonsense or frameshift mutations to those with splice-site mutations. When each patient was considered as an independent random event, the two groups differed (P < or = .05) for nearly every variable. Patients with nonsense or frameshift mutations were younger at onset and at diagnosis and had a higher frequency and mean number of tumors, supporting the correlation between nonsense and frameshift mutations and severe NF2. When each family was considered as an independent random event, statistically significant differences between the two groups were observed only for mean ages at onset and at diagnosis. A larger data set is needed to resolve these discrepancies. We observed retinal hamartomas and/or epiretinal membranes in nine patients from five families with four different nonsense mutations. This finding, which may represent a new genotype-phenotype correlation, merits further study. 相似文献
109.
110.
Ten patients with newly diagnosed B-chronic lymphocytic leukaemia were treated with cladribin orally for five days every four weeks with a median of four series. This is the first reported clinical study where a purine analogue is administered orally. The tumour reducing effect was fast. Eight out of 10 patients responded with a partial or clinical complete remission. Two of these were in molecular biological complete remission. With an observation time of 22 months we have seen no serious side effects so far. A randomized study (including a long term follow up) between chlorambucil, fludarabin and cladribin is needed to clarify the future role of cladribin in B-CLL treatment. 相似文献