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1.
Susan Krueger Gabrielle G. Long David R. Black Dennis Minor Pete R. Jemian G. William Nieman Richard A. Page 《Journal of the American Ceramic Society》1991,74(10):2538-2546
Small-angle X-ray scattering was used to follow the evolution of the pore size distribution during final-stage sintering of alumina and of alumina doped with 0.25 wt% magnesia. The volume-weighted (Guinier) results indicate that the effective size of the largest pores increases as the body goes from 97% to more than 99% dense. The surface-area-weighted (Porod) results show that the median size of the smallest pores decreases slightly over the same density range. Taken together, these data indicate that the pore size distribution becomes broader as final-stage densification proceeds. This was confirmed by a maximum entropy analysis, which was used to derive pore size distributions directly from the data. Finally, the evolution of the pore size distributions in alumina, with and without sintering aid, were compared. 相似文献
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Mathematical models, in the form of computer codes, are used to evaluate the performance of process and safety systems of CANDU nuclear reactors during normal operation and postulated accident conditions. To validate the models, predictions are made of the transient heat transfer and fluid mechanics processes in pressurized water loops following simulated pipe ruptures. These loops have the essential geometric and physical characteristics of a CANDU reactor primary heat transport system. Comparisons with data from loops of different scales over the conditions of interest (blowdown and cold water injection) are used to illustrate that the models predict the trends in the experiments adequately when the assumptions inherent in the model (e. g. equal steam and water velocities) are valid. To improve accuracy in cases where these assumptions do not apply, a more sophisticated representation of two-phase flow is required. 相似文献
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DA Papanicolaou JA Yanovski GB Cutler GP Chrousos LK Nieman 《Canadian Metallurgical Quarterly》1998,83(4):1163-1167
PURPOSE: We report stage specific followup guidelines based on our evaluation of the pattern of recurrence in 286 patients treated for local N0 or Nx renal cell carcinoma. MATERIALS AND METHODS: We retrospectively reviewed the clinical records of 286 patients with pT1 to pT3N0 or Nx renal cell carcinoma who underwent nephrectomy at our center between February 1985 and December 1994. In cases of later metastases the median interval to first metastasis, site of metastasis and method of diagnosis were correlated with the primary lesion stage. RESULTS: Metastases developed in 68 patients a median of 23 months after nephrectomy. Eight of the 113 patients with pT1 disease had metastases (median time to diagnosis 38 months), while 17 of 64 with pT2 disease and 43 of 109 with pT3 disease had metastases (medians 32 and 17 months, respectively). Of the 92 metastases 59 (64%) were asymptomatic, including 44 detected on routine chest x-rays (32) and blood tests (12). Isolated asymptomatic intra-abdominal metastases were diagnosed by surveillance computerized tomography in only 6 patients (9%). The remaining patients with metastases had associated clinical symptoms and/or abnormal results on interval tests that prompted further diagnostic studies. CONCLUSIONS: We confirmed that the risk of metastatic renal cell carcinoma is stage dependent. Therefore, surveillance protocols should be based on the pathological stage of the primary tumor. We recommend an annual chest x-ray, and serum liver function and alkaline phosphatase level tests for patients with pT1 disease. These studies are indicated beginning at 6 and 3 months for pT2 and pT3 disease, respectively, continuing every 6 months for 3 years and then annually. Surveillance computerized tomography should be performed at 24 and 60 months in patients with pT2 and pT3 disease or earlier when the results of any routine study are abnormal or clinical symptoms are present. Bone and brain surveillance studies should be prompted by site specific symptoms, elevated alkaline phosphatase levels or the diagnosis of metastasis at another site. 相似文献
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JC Watson TH Shawker LK Nieman HL DeVroom JL Doppman EH Oldfield 《Canadian Metallurgical Quarterly》1998,89(6):927-932
OBJECT: Pituitary surgery has been reported to produce remission of Cushing's disease with preservation of pituitary function in only 60 to 70% of patients. The inability to identify an adenoma accounts for most failed sellar explorations. Most negative surgical explorations occur in patients in whom magnetic resonance (MR) imaging of the pituitary demonstrates normal findings, which happens in at least 35 to 45% of patients with Cushing's disease. METHODS: To examine the usefulness of intraoperative ultrasonography (IOUS) for identifying an adenoma in patients with no demonstrable tumor (negative findings) on pituitary MR imaging. we prospectively assessed the results of IOUS in 68 patients with a negative (59 patients) or equivocal (nine patients) MR image from a consecutive series of 107 patients with Cushing's disease (64%). We compared surgical findings and outcomes in these 68 patients with a group of 68 patients with Cushing's disease and negative findings on MR imaging in whom IOUS was not available. Intraoperative ultrasonography localized a tumor in 47 (69%) of 68 patients with negative findings on MR imaging. Surprisingly, the size of the adenomas that were detected with IOUS compared with the size of those not detected did not differ (6.8+/-3.4 mm compared with 6.1+/-2.8 mm [mean+/-standard deviation], respectively [p=0.51). In four patients, no adenoma was found at surgery or in the pathological specimen ("true negative"). In eight patients, nine abnormalities detected by IOUS that were suspected adenomas were negative on exploration ("false positive"). Thus, IOUS has a sensitivity of 73% and a positive predictive value of 84% for detecting pituitary adenomas in patients with Cushing's disease and negative findings on MR imaging. Compared with the 68 patients who did not undergo IOUS. remission after surgery was improved (61 patients [90%] compared with 57 patients [84%]), the number of tumors found on exploration was increased (61 tumors compared with 51 tumors, p=0.02), and the number of hemihypophysectomies was decreased (five compared with 15; p=0.02) with IOUS. When the groups were compared after excluding patients with prior pituitary surgery, tumors were found in 91% versus 72% (p=0.008), and remission occurred in 95% versus 87% of patients, respectively, in the groups that had or did not have IOUS. CONCLUSIONS: The IOUS is a sensitive imaging modality when used in patients with Cushing's disease in whom findings on pituitary MR imaging are negative. The improved ability to detect and localize these tumors by using IOUS positively affects surgical outcome. 相似文献
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Paul H. Falcone Aaron C. Tribby Roxanne M. Vogel Jordan M. Joy Jordan R. Moon Chantelle A. Slayton Micah M. Henigman Joanne A. Lasrado Brandon J. Lewis Brenda A. Fonseca Kristin M. Nieman Kelli A. Herrlinger 《Journal of the International Society of Sports Nutrition》2018,15(1):58
Background
Proprietary spearmint extract (PSE) containing a minimum 14.5% rosmarinic acid and 24% total phenolic content, has evinced positive effects on cognition in individuals aged 50–70 with memory impairment after chronic supplementation. To address the growing interest in connecting mental and physical performance, the present study examined whether the nootropic effects of PSE translate into changes in reactive agility following daily supplementation with PSE.Methods
Utilizing a randomized, double-blind, placebo-controlled, parallel design, healthy, recreationally-active men and women (n?=?142) received 900?mg of PSE or placebo (PLA) daily for 90?days. Reactive agility, our primary outcome, was determined by measuring the number of hits and average reaction time (ART) on a Makoto Arena II, a 3600 audio-visual device that measures stationary, lateral, and multi-directional active choice reaction performance. Safety was evaluated using complete blood count, comprehensive metabolic panel, and blood lipids. Measurements were evaluated on days 7, 30, and 90 of supplementation.Results
An overall treatment effect (p?=?0.019) was evident for increased hits with PSE on the stationary test with footplates, with between group differences at Day 30 (PSE vs. PLA: 28.96?±?2.08 vs. 28.09?±?1.92 hits; p?=?0.040) and Day 90 (PSE vs. PLA: 28.42?±?2.54 vs. 27.02?±?3.55 hits; p?=?0.002). On the same task, ART improved (treatment effect, p?=?0.036) with PSE at Day 7 (PSE vs. PLA: 0.5896?±?0.060 vs. 0.6141?±?0.073?s; p?=?0.049) and Day 30 (PSE vs. PLA: 0.5811?±?0.068 vs. 0.6033?±?0.055?s; p?=?0.049). PSE also significantly increased hits (treatment effect, p?=?0.020) at Day 30 (PSE vs. PLA: 19.25?±?1.84 vs. 18.45?±?1.48 hits; p?=?0.007) and Day 90 (PSE vs. PLA: 19.39?±?1.90 vs. 18.66?±?1.64 hits; p?=?0.026) for the multi-directional test with footplates. Significant differences were not observed in the remaining Makoto tests. PSE was well tolerated as evidenced by no effects observed in the blood safety panels.Conclusions
The findings of the current study demonstrate that consumption of 900?mg of PSE improved specific measures of reactive agility in a young, active population.Trial registration
clinicaltrials.gov, NCT02518165. Registered August 7, 2015 – retrospectively registered.7.
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X He CM Goldsmith Y Marmary RB Wellner AF Parlow LK Nieman BJ Baum 《Canadian Metallurgical Quarterly》1998,5(4):537-541
1. The purpose of this study was to compare the effect of NIK-247 on muscarinic receptor subtypes with that of tacrine (THA) in rats. 2. NIK-247 and tacrine dose dependently inhibited the binding of [3H]pirenzepine (M1), [3H]AF-DX 384 (M2), and [3H]4-DAMP (M3). The IC50 values for NIK-247 were 4.4 x 10(-6) M, 1.1 x 10(-5) M, and 1.5 x 10(-5) M, respectively, whereas those for tacrine were 5.8 x 10(-7) M, 2.0 x 10(-6) M, and 5.8 x 10(-6) M, respectively. 3. Gpp[NH]p, a GTP analogue, slightly shifted the curve of displacement of [3H]AF-DX. 384 binding for NIK-247 to the right. However, Gpp[NH]p did not shift the curve of displacement of [3H]pirenzepine and [3H]4-DAMP binding to the right. 4. NIK-247 moderately decreased the rate of beating in right atrial preparations, but did not decrease it below 50% of control level. 5. These findings indicate that NIK-247 is an M1 antagonist, M2 partial agonist, and M3 antagonist. 相似文献
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Niessen Maurice A. J.; Dingemans Peter M. A. J.; van de Fliert Reinaud; Becker Hiske E.; Nieman Dorien H.; Linszen Don 《Canadian Metallurgical Quarterly》2010,22(4):935
[Correction Notice: An erratum for this article was reported in Vol 23(1) of Psychological Assessment (see record 2011-04411-006). Presents changes that are very small and do not in any way affect the findings of the research. These changes are explained in the correction.] Providers of mental health services need tools to screen for acute psychosis and ultrahigh risk (UHR) for transition to psychosis in help-seeking individuals. In this study, the Eppendorf Schizophrenia Inventory (ESI) was examined as a screening tool and for its ability to correctly predict diagnostic group membership (e.g., help seeking, mild psychiatric complaints, highly symptomatic mood or anxiety disorder, UHR, acute psychosis). Diagnostic evaluation with established instruments was used for diagnosis in 3 research samples. UHR status was assessed with the Structured Interview for Prodromal Symptoms/Scale of Prodromal Symptoms (Miller et al., 1999) and the Bonn Scale for the Assessment of Basic Symptoms Prediction list (Gross, Huber, Klosterk?tter, & Linz, 1987; Klosterk?tter, Hellmich, Steinmeyer, & Schulze-Lutter, 2001). This study showed that members of different diagnostic groups rate themselves significantly differently on the ESI and its subscales. A new subscale was constructed, the UHR–Psychosis scale, that showed good utility in detecting individuals with interview-diagnosed UHR status and acute psychosis. The scale is also sensitive to the threshold between UHR and acute psychosis. Practical applications of the ESI include use as a diagnostic tool within various settings. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
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