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141.
Forty-nine trained masters women endurance runners (mean = 42 km.wk-1) between the ages of 35 and 70 yr (mean = 46.4 +/- 8.3) were tested on a treadmill to examine cardiorespiratory fitness (VO2max and VO2 submax) in relation to age, training, and menopausal status. Although VO2max was lower with increasing age, no age group differences occurred in VO2 submax at 5.4 km.h-1, 8% treadmill grade. The younger runners (35-39 and 40-44 yr) had significantly higher VO2max than the other 5-yr competitive age groups (45-49, 50-55, 55-70 yr) (P < 0.01). HR max did not differ across age, but HR submax was higher with increasing age. Premenopausal, transitional, and post-menopausal women were not significantly different on any exercise variable when age and/or training differences among the groups were statistically controlled. A decrease in VO2max of 0.58 ml.kg-1 x min-1 x yr-1 was determined (r = -0.62). It was concluded that 1) these highly trained women runners had higher cardiorespiratory fitness than previously reported for women of comparable age, 2) menopausal status did not effect cardiorespiratory fitness when age and training were accounted for, and 3) regular physical training seems to prevent age-related changes in HR max in women, but not age-related changes in maximal oxygen uptake. 相似文献
142.
Wright Edward F.; Rule Brendan Gail; Ferguson Tamara J.; McGuire Gregory R.; Wells Gary L. 《Canadian Metallurgical Quarterly》1992,24(4):456
Examined the prediction that people who have misattributed dissonance arousal to an external source may come to question the appropriateness of this attribution and may then be motivated to alter their attitudes. This was tested by having an experimenter discredit the plausibility of an external source after misattribution had presumably occurred. 80 female undergraduates participated in the study, with 16 of these Ss serving as controls. 64 Ss were given a pill described as having either unpleasant side effects or no side effects and then were committed to write counterattitudinal essays under high-choice conditions. Some Ss were then told that a mistake had been made and that they had actually been given the other form of the pill. As predicted, Ss who had initially been led to believe that the pill had aversive side effects but were later told that it did not manifested behavior-consistent attitude change. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
143.
1. Completely isolated identified neurones from the right parietal ganglion of the pond snail Lymnaea stagnalis were investigated under two-electrode voltage clamp. Neuronal nicotinic acetylcholine receptor (AChR) currents were studied at low acetylcholine concentrations (< or = 200 nM). 2. Inhibition of the ACh-induced currents by three volatile general anaesthetics (halothane, isoflurane and methoxyflurane) and the specific inhibitor (+)-tubocurarine was studied as a function of temperature (over the range 4-25 degrees C). 3. The inhibition by the volatile anaesthetics increased (inhibition constants decreased) with decreasing temperature while the inhibition by (+)-tubocurarine did not change significantly near room temperature, but decreased at lower temperatures. The (+)-tubocurarine inhibition appeared to be competitive in nature and showed no significant voltage-dependence. 4. The van't Hoff plots (logarithms of the dissociation constants against reciprocal absolute temperature) were linear for the anaesthetics, but markedly non-linear for (+)-tubocurarine. From these plots, values for the changes in the standard Gibbs free energy delta G degrees water-->AChR, enthalpy delta H degree water-->AChR, entropy delta S degree water-->AChR and heat capacity delta Cp degree water-->AChR were determined. Tubocurarine was found to bind very much tighter to the receptor than the volatile anaesthetics due, entirely, to a favourable increase in entropy on binding. 5. A comparison between the temperature-dependence of the anaesthetic inhibition of the ACh receptor and that of general anaesthetic potencies in animals indicates that the temperature-dependence of animal potencies might be simply accounted for in terms of changes in anaesthetic/receptor binding. 相似文献
144.
An HPLC-fluorescence assay has been developed for the determination of the activity of rat renal cytosolic cysteine conjugate beta-lyase. The method is based on isocratic HPLC separation and fluorescence detection of pyruvic acid, derivatized with o-phenylenediamine (OPD), and is shown to be rapid, specific, and very sensitive. The assay has been evaluated with two model substrates for rat renal cytosolic beta-lyase, notably S-1,2-dichorovinyl-L-cysteine (DCVC) and S-2-benzothiazolyl-L-cysteine (BTC). Equimolar formation of pyruvic acid and 2-mercaptobenzothiazole, a chromophoric thiol, indicated that pyruvic acid formation actually reflects the beta-elimination activity of beta-lyase during the beta-elimination of BTC. From this it follows that the pyruvic acid assay can be applied to the measurement of the beta-elimination activity of this enzyme, independent of the presence of chromophoric groups or radiolabels in substrates. Due to the large linear range and the very high sensitivity of the present HPLC-fluorescence assay (detection limit, 7.5 pmol of pyruvic acid), both good and poor substrates of beta-lyase can be measured. Enzyme kinetic data are presented for the model substrates BTC and DCVC and for four structurally related S-2,2-difluoroethyl-L-cysteine conjugates. 相似文献
145.
146.
A 4.5-wk-old lynx (Felis lynx) was presented for necropsy with a history of poor growth, mild diarrhea, anemia, and lethargy. The liver was enlarged and had a 7 mm long fracture that resulted in severe intraabdominal hemorrhage and death. Microscopic lesions were indicative of severe ulcerative cystitis and septicemia. Pure cultures of Salmonella arizonae were isolated from the liver, kidney, and spleen. Based on differences in the chronicity of inflammation in the urinary bladder versus other organs, we speculate that chronic cystitis caused by S arizonae lead to septicemic infection. 相似文献
147.
NP Shirodkar PS Chopra M Marker KD Murphy A Dhamoon OJ Kwon 《Canadian Metallurgical Quarterly》1997,21(5):340-345
In this study, we evaluated the permeation of piperacillin (PIPC), imipenem (IPM), amikacin (AKM), gentamicin (GM), ofloxacin (OFLX), levofloxacin (LVFX), ciprofloxacin (CPFX) and sparfloxacin (SPFX) through Pseudomonas aeruginosa biofilm with a simple new method. Bacteria used were a leucine-requiring mucoid mutant. Bacteria were grown on the membrane of a cell culture insert in chemically defined medium and incubated at 37 degrees C for 5 days. At days 0, 1, 3 and 5, the penetration rates through the biofilms were measured. PIPC and IPM demonstrated relatively high permeation both with penetration rates at day 5 of 50%, whereas AMK and GM, which are aminoglycosides, showed low permeation both with penetration rates after day 1 of less than 25%. Among the 4 fluoroquinolones, LVFX and SPFX demonstrated excellent permeation with penetration rates that reached 100% from day 0 to 5, while OFLX and CPFX showed almost the same permeation as IPM. This method of measuring penetration rates of antimicrobial agents through biofilm is very simple and useful for the evaluation of antibiotics against biofilm-forming bacteria. 相似文献
148.
Letzring Tera D.; Wells Shannon M.; Funder David C. 《Canadian Metallurgical Quarterly》2006,91(1):111
Triads of unacquainted college students interacted in 1 of 5 experimental conditions that manipulated information quantity (amount of information) and information quality (relevance of information to personality), and they then made judgments of each others' personalities. To determine accuracy, the authors compared the ratings of each judge to a broad-based accuracy criterion composed of personality ratings from 3 types of knowledgeable informants (the self, real-life acquaintances, and clinician-interviewers). Results supported the hypothesis that information quantity and quality would be positively related to objective knowledge about the targets and realistic accuracy. Interjudge consensus and self-other agreement followed a similar pattern. These findings are consistent with expectations based on models of the process of accurate judgment (D. C. Funder, 1995, 1999) and consensus (D. A. Kenny, 1994). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
149.
150.
BM de Rooij PJ Boogaard JN Commandeur NJ van Sittert NP Vermeulen 《Canadian Metallurgical Quarterly》1997,54(9):653-661
OBJECTIVE: To evaluate the use of urinary mercapturic acids as a biomarker of human exposure to allyl chloride (3-chloropropene) (AC). During three regular shut down periods in a production factory for AC, both types of variables were measured in 136 workers involved in maintenance operations. METHODS: Potential airborne exposure to AC was measured by personal air monitoring in the breathing zone. In total 205 workshifts were evaluated. During 99 workshifts no respiratory protection equipment was used. Mercapturic acid metabolites were measured in urinary extracts by gas chromatography-mass spectrometry (GC-MS). RESULTS: During 86 work shifts when no respiratory protection was used the air concentrations of AC were below the Dutch eight hour time weighted average (8 h-TWA) occupational exposure limit (OEL) of AC (3 mg/m3), whereas in 13 workshifts the potential exposure, as measured by personal air monitoring, exceeded the OEL (3.3 to 17 mg/m3). With the aid of GC-MS, 3-hydroxypropylmercapturic acid (HPMA) was identified as a minor and allylmercapturic acid (ALMA) as a major metabolite of AC in urine samples from the maintenance workers exposed to AC. The concentrations of ALMA excreted were in a range from < 25 micrograms/l (detection limit) to 3550 micrograms/l. The increases in urinary ALMA concentrations during the workshifts correlated well with the 8h-TWA air concentrations of AC (r = 0.816, P = 0.0001, n = 39). Based on this correlation, for AC a biological exposure index (BEI) of 352 micrograms ALMA/g creatinine during an eight hour workshift is proposed. In some urine samples unexpectedly high concentrations of ALMA were found. Some of these could definitely be attributed to dermal exposure to AC. In other cases garlic consumption was identified as a confounding factor. CONCLUSION: The mercapturic acid ALMA was identified in urine of workers occupationally exposed to airborne AC and the increase in ALMA concentrations in urine during a workshift correlated well with the 8 h-TWA exposure to AC. Garlic consumption, but not smoking, is a potential confounding factor for this biomarker of human exposure to AC. 相似文献