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RR Stotts AR Twardock WM Haschek BW Choi KL Rinehart VR Beasley 《Canadian Metallurgical Quarterly》1997,35(6):937-953
The distribution of tritiated dihydromicrocystin [3H]2H-MCLR was studied in anesthetized specific-pathogen-free pigs. Two doses were administered i.m. and one dose was given via an isolated ileal loop. At 4 hr after i.v. administration of the toxin at 25 micrograms/kg, 64.6% of the total dose (%TD) was located in the liver, with smaller amounts distributed to the kidneys (1.2% TD), lungs (1.75% TD), heart (0.22% TD), ileum (0.13% TD) and spleen (0.04% TD). A similar distribution was found at 4 hr postdosing in pigs given 75 micrograms/kg, although the liver contained a lower fraction of the total dose, at 46.99% TD, and the kidneys had somewhat more, at 2.19% TD, than the low dose. At the high dose, the fractions of the amount given accounted for by the lungs (0.55% TD), heart (0.23% TD), ileum (0.20% TD) and spleen (0.07% TD) were similar to those at the low dose. The livers of the pigs given 75 micrograms/kg via the ileal loop, at 5 hr postdosing, contained 49.5% TD and the ileum had 33.94% TD. Smaller amounts were distributed to kidneys (1.04% TD), lungs (0.65% TD), heart (0.81% TD) and spleen (0.16% TD). The livers of both groups dosed at 75 micrograms/kg contained higher concentrations of toxin, but lower percentages of the total dose, than the livers of pigs dosed at 25 micrograms/kg. Larger increases in serum arginase in the two 75 micrograms/kg groups were associated with histological evidence of more severe liver damage than at the 25 micrograms/kg dose. Analysis of radiolabeled compounds from hepatic tissue using fast atom bombardment mass spectrometry determined that the primary constituent was [3H]2H-MCLR, but two minor radioactive components were also isolated. These findings indicate that [3H]2H-MCLR is rapidly concentrated in the liver of swine, whether given i.v. or via an isolated ileal loop, that at extremely toxic doses uptake is slowed, and that it is as toxicologically active as the parent compound. 相似文献
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These are exciting times in nursing, with great possibilities for reforming nursing as we now know it. The desired outcome is to improve any nurse's ability to care for individuals, families, and communities wherever they are. We believe that articulating CBN and CHN practice is a necessary first step in achieving this outcome; however, it now becomes our challenge to advance this vision. We ask you to join us in this endeavor. 相似文献
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Joy M Schmitz Angela L Stotts Marc E Mooney Katherine A Delaune Gerard F Moeller 《Nicotine & tobacco research》2007,9(6):699-709
Gender data for bupropion suggest that it may be a particularly effective smoking cessation medication for women. It is not known whether the efficacy of this pharmacotherapy differs as a function of the psychotherapy with which it is administered. This study used a two level factorial design to examine the independent and interactive effects of medication (bupropion 300 mg/day vs. placebo) and psychotherapy (cognitive-behavioral therapy [CBT] vs. supportive therapy [ST]). In addition to testing the hypothesis that bupropion with CBT would be most effective of all the treatments, we examined medication compliance and its role in the efficacy of bupropion. Participants were 154 women, aged at least 30 years and smoking more than 10 cigarettes/day. Compliance with study medication was assessed using Medication Event Monitoring Systems (MEMS) over 7 weeks of treatment. Psychological interventions were delivered in 60-min weekly group sessions. Longitudinal analysis of abstinence outcomes from end of treatment (EOT) through 12 months after treatment revealed a significant interaction of medication and therapy. Higher abstinence rates at EOT and 3-, 6-, 9-, and 12-month follow-ups were observed when bupropion was delivered concurrently with CBT (44%, 24%, 30%, 23%, 17%) rather than with ST (18%, 1%, 8%, 5%, 2%). The bupropion-CBT combination, however, was not clearly superior to placebo, regardless of therapy assignment. Higher rates of medication compliance were positively predictive of abstinence, and this effect was most evident in the placebo condition. Findings provide only modest support for CBT as the preferred type of intensive therapy in conjunction with bupropion in women. 相似文献
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Prutchi D. Prince J.L. Stotts L.J. 《Components and Packaging Technologies, IEEE Transactions on》1999,22(3):390-398
There is a growing need for the inclusion of nonvolatile memory within implantable medical devices in order to store product identification, operating parameters, calibration information, as well as patient and diagnostic data. Due to the critical nature of the application however, the data retention reliability is of utmost importance. In the case of nonvolatile memories, a source of concern regards their exposure to ionizing radiation as the result of diagnostic or therapeutic procedures performed on the patient. This paper reports on X- and gamma-ray experiments and calculations on a representative modern electrically erasable and programmable read-only memory (EEPROM) (Atmel 24C64). No transient upsets due to 150 kVp X-rays were observed in 10 unbiased and five biased DTU's up to the maximum achievable 27 rad(Si)/s for a total dose of 200 rad(Si). Unbiased parts had no failure to an average total-dose of 40.9 krad(Si). The lowest failure level observed for an unbiased part was 30.0 krad(Si). In the biased parts, the read-mode operating current increased as a function of total dose from 47 μA prior to exposure to 385 μA at 30 krad(Si). The mean highest no-failure level for 10 unbiased parts exposed to Co60 gamma-rays was 36.9 krad(Si) with a sigma of 2.3. Five biased DUT failures occurred at a mean of 27.84 krad(Si) with a sigma of 2.42. The analysis of these data, in comparison to maximum therapeutic photon radiation doses suggest that floating-gate EEPROM technology is reliable in the presence of photon ionizing-radiation exposures typical of medical diagnostic and therapeutic environments 相似文献
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The needs of engineers in their interaction with engineering data bases are very different from those of their counter-parts in the business world. Business data base management system interfaces typically provide only a single mode of textual communication, usually a structured query language. However, in an idealengineering data base interface, an engineer would be able to define constraints, give examples, point at parts of pictures, and (sometimes) use several modes of communication simultaneously. The paper presents an example from an engineering design application to show how a traditional query language can be enhanced to accommodate the engineering needs. The paper further describes a conceptual approach for multimodal engineering data base interface combining multipurpose graphics, an engineering query language, and other interface methodologies in an engineering workstation environment. 相似文献
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This work examines scheduling for a real-time multiprocessor (MAFT) in which both hard deadlines and fault-tolerance are necessary system components. A workload for this system consists of a set of concurrent dependent tasks, each with some execution frequency; tasks are also fully ordered by priority. Fault tolerance mechanisms include hardware-supported voting on computation results as well as on task starts, task completions, and branch conditions. The distributed agreement mechanism used on system-level decisions adds a variable threading delay to the run time of each copy of a task. These delays make current schedule verification techniques inapplicable. In the most general execution profile, each processor in the system runs a subset of the tasks, with different tasks possibly having different frequencies. In this work, however, we restrict attention to a special class of workloads, termed uni-schedule, in which each processor executes the entire task set, using the multiple processors to implement full redundancy. In addition, all tasks are assumed to have the same periodicity. Given these restrictions, we produce stable schedules consistent with the initial workload specifications. Algorithms are first given for uni-schedule workloads with no run-time branches, and then for uni-schedule workloads with branches. 相似文献
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Cinciripini Paul M.; Blalock Janice A.; Minnix Jennifer A.; Robinson Jason D.; Brown Victoria L.; Lam Cho; Wetter David W.; Schreindorfer Lisa; McCullough James P. Jr.; Dolan-Mullen Patricia; Stotts Angela L.; Karam-Hage Maher 《Canadian Metallurgical Quarterly》2010,78(1):44
Objective: The objective of this study was to evaluate a depression-focused treatment for smoking cessation in pregnant women versus a time and contact health education control. We hypothesized that the depression-focused treatment would lead to improved abstinence and reduced depressive symptoms among women with high levels of depressive symptomatology. No significant main effects of treatment were hypothesized. Method: Pregnant smokers (N = 257) were randomly assigned to a 10-week, intensive, depression-focused intervention (cognitive behavioral analysis system of psychotherapy; CBASP) or to a time and contact control focused on health and wellness (HW); both included equivalent amounts of behavioral and motivational smoking cessation counseling. Of the sample, 54% were African American, and 37% met criteria for major depression. Mean age was 25 years (SD = 5.9), and women averaged 19.5 weeks (SD = 8.5) gestation at study entry. We measured symptoms of depression using the Center for Epidemiological Studies–Depression Scale (Radloff, 1977). Results: At 6 months posttreatment, women with higher levels of baseline depressive symptoms treated with CBASP were abstinent significantly more often, F(1, 253) = 5.61, p = .02, and had less depression, F(1, 2620) = 10.49, p = .001, than those treated with HW; those with low baseline depression fared better in HW. Differences in abstinence were not retained at 6 months postpartum. Conclusions: The results suggest that pregnant women with high levels of depressive symptoms may benefit from a depression-focused treatment in terms of improved abstinence and depressive symptoms, both of which could have a combined positive effect on maternal and child health. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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