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41.
Psychological processes may play a role in the evaluation of the effectiveness of exercise and subsequent food intake. In order to further investigate this phenomenon, the effects of the timing of exercise relative to an eating opportunity were evaluated. Female undergraduate participants who were of average weight and did not exercise regularly were randomly assigned to one of three conditions (exercise before eating [n = 10], exercise after eating [n = 11], or no exercise [n = 12]). Expectations of the effectiveness of the exercise, value of dieting, and intake were assessed. Participants who exercised after eating had higher expectations of the effectiveness of the exercise than those who exercised before eating, while those who exercised before eating reported valuing dieting more than controls. No effects on intake emerged; therefore, there appears to be a disconnect between dieting appraisals and actual eating behaviour. The results are discussed in relation to theories on conflicting goals. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
42.
Alkmin  L. B.  Chaia  N.  Utada  S.  Cormier  J.  Baldan  R.  Coelho  G.  Nunes  C. A. 《Metallurgical and Materials Transactions A》2021,52(6):2589-2600

The present investigations focused on the thermal oxidation of two variants of MAR-M246 alloy having the same contents of Ta and Nb in at. pct, considering the effects of total replacement of Ta by Nb. The alloys were produced by investment casting using high purity elements in induction furnace under vacuum atmosphere. The alloys were oxidized pseudo-isothermally at 800 °C, 900 °C and 1000 °C up to 1000 hours under lab air. Protective oxidation products growing on the surface of the oxidized samples were mainly Al2O3, Cr2O3. Other less protective oxide such as spinels (NiCr2O4 and CoCr2O4) and TiO2 were also detected as oxidation products. The conventional alloy exhibited slight internal oxidation at 800 °C and an enhanced resistance at 900 °C and 1000 °C. The Nb-modified alloy presented an exacerbated internal oxidation and nitridation at 900 °C and 1000 °C and an enhanced resistance at 800 °C. At 1000 °C, Nb-modified alloy was particularly affected by excessive spalling as the main damage mechanisms. From a kinetic point of view, both alloys exhibit the same behavior at 800 °C and 900 °C, with kp values typical of alumina forming alloys (2 × 10−14 to 3.6 × 10−13 g2 cm−4 s−1). However, Ta modified alloys exhibited superior oxidation resistance at 1000 °C when compared to the Nb modified alloy due to better adherence of the protective oxide scale.

  相似文献   
43.
Municipal biosolids are a source of nutrients for crop production. Beneficial Management Practices (BMPs) can be used to minimize the risk of contamination of adjacent water resources with chemical or microbial agents that are of public or environmental health concern. In this field study, we applied biosolids slurry at a commercial rate using either subsurface injection or broadcast application followed by incorporation. Precipitation was simulated at 1, 3, 7, 22, 36 and 266 days post-application on 2 m2 microplots to evaluate surface runoff of 9 model pharmaceuticals and personal care products (PPCPs), atenolol, carbamazepine, cotinine, gemfibrozil, naproxen, ibuprofen, acetaminophen, sulfamethoxazole and triclosan. In runoff from the injected plots, concentrations of the model PPCPs were generally below the limits of quantitation. In contrast, in the broadcast application treatment, the concentrations of atenolol, carbamazepine, cotinine, gemfibrozil, naproxen, sulfamethoxazole and triclosan on the day following application ranged from 70-1477 ng L− 1 in runoff and generally declined thereafter with first order kinetics. The total mass of PPCPs mobilized in surface runoff per m2 of the field ranged from 0.63 µg for atenolol to 21.1 µg for ibuprofen. For ibuprofen and acetaminophen, concentrations in runoff first decreased and then increased, suggesting that these drugs were initially chemically or physically sequestered in the biosolids slurry, and subsequently released in the soil. Carbamazepine and triclosan were detected at low concentrations in a runoff event 266 days after broadcast application. Overall, this study showed that injection of biosolids slurry below the soil surface could effectively eliminate surface runoff of PPCPs.  相似文献   
44.
A theoretical analysis is reported in the present work to quantify the increase of radiative emission due to turbulence for hydrogen and hydrogen-enriched methane diffusion flames burning in air. The instantaneous thermochemical state of the reactive mixture is described by a flamelet model along with a detailed chemical mechanism. The shape of the probability density function (pdf) of mixture fraction is assumed. The results show that turbulent fluctuations generally contribute to reduce the Planck mean absorption coefficient of the medium, in contrast with the blackbody emissive power, which is significantly increased by turbulence. If the turbulence level is relatively small, the influence of turbulence on the absorption coefficient is marginal. Otherwise, fluctuations of the absorption coefficient of the medium should be taken into account. The scalar dissipation rate and the fraction of radiative heat loss have a much lower importance than the turbulence intensity on the mean radiative emission.  相似文献   
45.
46.
Arylsulfate sulfotransferase purified from Eubacterium A-44 has higher specific activity than the enzymes from Klebsiella K-36 and Haemophilus K-12. Propylparaben and butylparaben were good substrates among several parabens. The antibacterial activity of parabens was reduced by the sulfation of the phenolic hydroxy group. Tyrosine-containing peptides, kyotorphin, enkephalin and cholecystokinin non-sulfate, were effective as acceptor substrates by A-44, K-36 and K-12 sulfotransferases.  相似文献   
47.
RATIONALE AND OBJECTIVES: The authors performed this study to evaluate the pharmacokinetics, dialysability, and safety of gadodiamide injection in patients with severely reduced renal function not treated with renal replacement therapy and patients undergoing hemodialysis or continuous ambulatory peritoneal dialysis. MATERIALS AND METHODS: Twenty-seven patients--nine with severely reduced renal function (glomerular filtration rate, 2-10 mL/min), nine undergoing hemodialysis, and nine undergoing continuous ambulatory peritoneal dialysis--were followed up for 5, 8, and 22 days, respectively, after receiving gadodiamide injection (0.1 mmol per kilogram body weight). RESULTS: Gadodiamide injection caused no changes in renal function. In patients with severely reduced renal function, the elimination half-life of gadodiamide injection was prolonged (34.3 hours +/- 22.9) compared with data in healthy volunteers (1.3 hours +/- 0.25). An average of 65% of the gadodiamide injected was eliminated during a hemodialysis session. After 22 days of continuous ambulatory peritoneal dialysis, 69% of the total amount of gadodiamide was excreted; this reflects the low peritoneal clearance. In all patients, no metabolism or transmetallation of gadodiamide was found. There were no contrast material-related adverse events. CONCLUSION: Gadodiamide is dialysable and can safely be used in patients with severely impaired renal function or those undergoing hemodialysis or continuous ambulatory peritoneal dialysis. No precautions to increase the elimination are necessary.  相似文献   
48.
We analysed the occurrence of anti-neutrophil cytoplasmic antibodies (ANCA) in sera of 191 patients with glomerulonephritis (76 females and 115 males) by the standard indirect immunofluorescence method (IIF). The presence of ANCA was demonstrated in sera of 4.4% (8/181) patients with idiopathic glomerulonephritis (GN) and in 30% (3/10) of patients with rapidly progressive glomerulonephritis (RPGN), as a form of renal limited vasculitis. In the experimental part of our study we analysed the influence of GN ANCA-negative sera on the neutrophil function in vitro and compared with the effect of ANCA-positive sera (titre > or = 4:40) from systemic vasculitis (SV) patients with renal involvement. The activation of neutrophils was established by reactive oxygen species (ROS) production and the ability of superoxide anion to reduce ferrocytochrome c. Among 30 ANCA-negative GN sera 20% (6/30) revealed the ability to activate neutrophils isolated from healthy donor. Remaining ANCA-negative GN sera and all sera from normal healthy individuals (negative control group) did not affect the neutrophil function and did not induce the superoxide anion production. Their effect was similar to the second negative reference system without serum. Only 33% (3/9) of high titre ANCA-positive sera (> or = 1:40) from SV patients were able to activate neutrophils and to produce the superoxide anion with following ferrocytochrome c reduction, but the effect of activation was most powerfully expressed (three times greater than by GN ANCA-negative sera). The remaining ANCA-positive sera and all SV ANCA-negative sera did not affect the neutrophil function in vitro. These experimental data indicate that the presence of ANCA in GN sera is not necessary to induce neutrophil activation in vitro. On the other hand the influence of the SV ANCA-positive sera was most powerful expressed, although only 33% of sera were able to activate neutrophils in vitro. Our results indicate that not always ANCA presence in serum was connected with the ability to neutrophil activation in vitro. It is possible that in ANCA-negative sera other factors were able to activate neutrophils in vitro, but the effect of activation was markedly lower.  相似文献   
49.
The authors have designed and constructed a plant-optimize synthetic gene encoding the Escherichia coli heat-labile enterotoxin B subunit (LT-B), for use in transgenic plants as an edible vaccine against enterotoxigenic E. coli. Expression of the synthetic LT-B gene in potato plants under the control of a constitutive promoter yielded increased accumulation of LT-B in leaves and tubers, as compared to the bacterial LT-B gene. The plant-derived LT-B assembled into native pentameric structures as evidenced by its ability to bind ganglioside. The authors demonstrated immunogenicity by feeding mice the raw tubers and comparing the anti-LT-B serum IgG and faecal IgA to that produced in mice gavaged with bacterial LT-B. Mice were fed three weekly doses of 5 g tuber tissue containing either 20 or 50 micrograms LT-B, or gavaged weekly with 5 micrograms of LT-B from recombinant E. coli. One week after the third dose, mice immunized with potato LT-B had higher levels of serum and mucosal anti-LT-B than those gavaged with bacterial LT-B. Mice were challenged by oral administration of 25 micrograms LT, and protection assessed by comparing the gut/carcass mass ratios. Although none of the mice were completely protected, the higher dose potato vaccine compared favourably with the bacterial vaccine. These findings show that an edible vaccine against E. coli LT-B is feasible.  相似文献   
50.
PURPOSE: Prostate-specific antigen (PSA) is extensively used in case selection and outcome evaluation after treatment of clinically localized prostate cancer. Careful case selection can have a profound impact on pathologic findings and ultimate outcome. In addition, salvage treatment is frequently initiated at the time of biochemical relapse rather than clinical recurrence. Consequently, patterns of failure can be significantly altered compared to previous times when PSA was not available. To better understand the impact of PSA on pathologic findings, outcome, and salvage treatment, we reviewed our experience in the PSA era with clinical Stage T1-2 prostate cancer treated with radical prostatectomy. METHODS AND MATERIALS: Between 1987 and 1993, 423 cases could be identified with clinical Stage T1-2 prostate cancer treated with radical prostatectomy. The distribution of cases by pretreatment PSA levels was as follows: < or = 4 ng/ml (18%), 4-10 ng/ml (42%), 10-20 ng/ml (21%), > 20 ng/ml (14%), and unknown (5%). The median pretreatment PSA level for the entire group was 8.0 ng/ml. Sixteen patients received adjuvant or neoadjuvant androgen suppression and 13 received postoperative radiotherapy. Only 31 patients (7%) had pathologically positive pelvic lymph nodes. The overall margin involvement rate was 46%. Fifty-three percent of patients had surgical Gleason scores > or = 7, and 65% had extracapsular extension. The median follow-up time was 41 months. RESULTS: The projected overall survival at 7 years after surgery was 90%. The 5-year clinical relapse-free survival rate was 84%. At 5 years, the local control and distant failure rates were 92% and 91%, respectively. Biochemical relapse was defined as a detectable or rising PSA level after prostatectomy. The 5-year biochemical relapse-free survival (bRFS) rate was 59%. The 5-year RFS was 88% in patients with preoperative PSA levels < or = 4, 62% for 4-10, 48% for 10-20, and 31% for > 20. Combining the two independent preoperative variables, iPSA and biopsy GS (bGS), two risks groups were defined: low risk [initial PSA (iPSA) levels < or = 10.0 and bGS < or = 6] and high risk (iPSA levels > 10.0 ng/ml or bGS > or = 7). The 5-year bRFS rate for the low-risk cases was 81% vs. 40% for high-risk cases (p < 0.001). On multivariate analysis, three factors independently predicted biochemical relapse: iPSA levels (p = 0.005), Gleason score from the surgical specimen (sGS) (p = 0.002), and positive surgical margins (p < or = 0.001). The 5-year bRFS rates for margin positive vs. margin negative patients were 37% vs. 78%, respectively. The 5-year bRFS rates for GS > or = 7 vs. GS > or = 6 were 42% vs. 80%, respectively. All clinical relapses were accompanied by a rise in PSA. In patients who manifested biochemical failure followed by a clinical failure, the median interval between the PSA rise and clinical failure was 19 months (range 7-71). Margin involvement was the only independent predictor of local failure (p = 0.019). The 5-year local failure-free survival for negative margin cases was 96% vs. 87% for positive margin cases (p = 0.012). Lymph node (LN) involvement and high-risk group were the two independent predictors of distant failure. The 5-year distant failure-free survival for negative LN cases was 94% vs. 67% for positive LN cases (p < 0.001). The 5-year distant failure-free survival for low-risk cases was 97% vs. 85% for high-risk cases (p = 0.005). For the 124 patients failing biochemically, 85 were observed and 39 were treated either with radiation or androgen deprivation. With a median follow-up of 32 months, the clinical disease relapse-free survival was 79% for the treated patients vs. only 32% for the patients observed (p < 0.001). CONCLUSION: Pretreatment PSA is the most potent clinical factor independently predicting biochemical relapse, thereby allowing markedly better case selection. Achieving negative margins, even in relatively advanced disease, provides excellent lon  相似文献   
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