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81.
The term “conjugated linoleic acid” (CLA) refers to a group of positional and geometric isomers that are derived from linoleic
acid and are found primarily in meat and milk products from ruminant animals. Due to the array of putative benefits associated
with various forms of CLA, there has been recent interest in supplementing human diets with these fatty acids especially when
weight loss is desired. However, in many animal models, CLA has been shown to decrease milk fat production. There is some
concern, therefore, that maternal CLA supplementation during lactation might inadvertently decrease nutrient supply to the
nursing infant. However, there is only limited research on the effect of CLA consumption on milk fat content in women. Based
on previously published work from our laboratory, we hypothesized that CLA supplementation would reduce the milk fat percentage
in lactating women in a dose-dependent manner. Breastfeeding women (n = 12) were assigned randomly to treatments of 4 g/day safflower oil (SFO), 2 g/day CLA plus 2 g/day SFO, or 4 g/day CLA in
a double blind, 3 × 3 Latin square design. Conjugated linoleic acid supplements contained approximately equal amounts of cis9,trans11–18:2 and trans10,cis12–18:2; the two most common isoforms of CLA. Milk was collected by complete breast expression on the last day (day 5) of
each intervention period and analyzed for macronutrient and fatty acid composition. On day 4 of each intervention period,
infant milk consumption was estimated by 24 h weighing of the infant. Washout periods were 9 days in length. We observed a
dose-dependent increase in the concentrations of cis9,trans11–18:2 and trans10,cis12–18:2 in the milk fat. However, we detected neither a change in overall macronutrient composition nor infant milk consumption.
These data do not support those obtained from animal models or our previous human work suggesting that consumption of CLA
mixtures necessarily reduces milk fat. It is possible that either (1) the interpretation of our previously published data
should be reevaluated, and/or (2) there are important intra- and inter-species differences in this regard. 相似文献
82.
Substantial research suggests that the t10,c12–18:2, but not the c9,t11–18:2, isomer of conjugated linoleic acid (CLA) reduces milk fat synthesis in lactating bovine and rodent species. Because
fat is the major energy-yielding component in human milk, we were interested in whether this is true for women as well. Thus,
the effects of c9,t11–18:2 and t10,c12–18:2 on milk fat were examined in breast-feeding women (n = 12) in a double-blind, placebo-controlled, crossover study with latin-square design. The study was divided into six periods:
baseline (3 days), three intervention periods (5 days each), and two washout periods (9 days each). During each intervention
period, women consumed 750 mg/day of a supplement containing predominantly c9,t11–18:2, t10,c12–18:2, or 18:1 (olive oil placebo). Milk was collected by complete breast expression on the final day of each period. Infant
milk consumption was estimated by 24 h weighing on the penultimate day of each intervention and washout period, and maternal
adiposity (% body fat) was determined at baseline using dual energy X-ray absorptiometry. Milk c9,t11–18:2 and t10,c12–18:2 concentrations were greater (P < 0.05) during the corresponding CLA treatment periods as compared to the placebo period, providing strong evidence of subject
compliance. Both CLA isomers were transferred into milk fat at relatively high efficiency; average transfer efficiency was
estimated to be 23.3%. Compared to the placebo treatment, milk fat content was not reduced during either CLA treatment. Data
indicate that body fatness did not modify any putative effect of isomeric CLA consumption on milk fat concentration. The evidence
from this study suggests that the sensitivity of lactating women’s mammary tissue to an anti-lipogenic effect of the t10,c12–18:2 isoform of CLA may be less than previously hypothesized. 相似文献
83.
M.J. Anderson K. McGuire R.C. Zante W.J. Ion A. Rosochowski J.W. Brooks 《Journal of Materials Processing Technology》2013,213(1):111-119
The dies used in the extrusion of nickel based super alloys are subject to severe mechanical and thermal stresses, resulting in shortened life and high manufacturing costs. It is necessary to understand the dominant damage mode in order to guide improvements for increased tool life. The operation under examination consists of the hot extrusion of a nickel based superalloy using nitrided hot work tool steel, glassed workpieces and graphite lubrication. The investigation was conducted through a combination of metallurgical analysis, metrology and finite element analysis. Out of the damage modes observed under these conditions, the plastic deformation of the substrate was found to be the cause for tool failure. This paper discusses the relationship between plastic deformation of the substrate and the formation of scoring marks, which fail the die. 相似文献
84.
Gross PA Patriaco D McGuire K Skurnick J Teichholz LE 《The Joint Commission journal on quality improvement》2002,28(10):566-573
BACKGROUND: Telemetry monitoring is widely used in hospitals; the importance of being able to monitor and examine dysrhythmias has been universally accepted. Yet it is often used for patients who do not actually require this technology. A model to improve the efficiency of telemetry use entailed the use of an advanced practice nurse (APN; identical to a nurse practitioner) to provide concurrent review and intervention of floating telemetry, which is available for patients independently of the floor location and who do not need an intensive care unit bed. ADDRESSING OVERUSE: The demand for floating telemetry at Hackensack University Medical Center had equaled or exceeded the telemetry availability virtually 100% of the time, even after local guidelines had been disseminated in 1998. The APN carried out concurrent monitoring and intervened with the attending physician when patients were on telemetry for longer than 48 hours and did not meet the local telemetry guidelines. RESULTS: The mean number (standard error [SE]) of hours per patient declined from 65.2 +/- 0.7 hours (95% confidence interval, 63.8 to 66.6 hours) for the 11 months before the intervention to a mean of 49.6 +/- 0.4 hours (95% confidence interval, 48.7 to 50.2 hours) for the 29 months after intervention--representing a decrease of 34% (p < 0.0001). This decrease led to an increase in the number of patients per month put on telemetry. DISCUSSION: The APN model, an aggressive approach that induced change almost immediately, was then applied to other quality improvement projects. 相似文献
85.
The effect of converting from pravastatin to simvastatin on the pharmacodynamics of warfarin 总被引:1,自引:0,他引:1
Glycosylated amino acids and glycosylated human serum albumin reduce nitrite to nitric oxide under anaerobic conditions. The amount of nitric oxide produced was recorded by generation of nitrosoHb from deoxyHb. Without preincubation after the addition of sodium nitrite, glucose or a mixture of glucose with amino acid or serum albumin did not cause spectrophotometrically detectible transformation of deoxyHb into nitrosoHb. The generation of NO increased with an increase in content of colored "final" products of amino acid and serum albumin glycosylation in the incubation mixture. The incubation of blood plasma of patients with diabetes mellitus with nitrite also resulted in the increased production of NO as compared to blood plasma of healthy subjects. During the incubation of healthy subjects' blood plasma with nitrite a small amount of NO was produced. The removal of low-molecular-weight compounds was accompanied by a significantly decreased generation of NO by blood plasma. 相似文献
86.
OBJECTIVE: To determine whether administration of commercially available Escherichia coli antiserum to neonatal foals would affect serum IgG concentration or morbidity and mortality rates during the first 60 days of life. DESIGN: Randomized controlled trial. ANIMALS: 271 neonatal foals on 4 well-managed farms. PROCEDURE: Foals were randomly assigned to a treatment or control group. All foals were allowed to suckle colostrum normally. In addition, treatment-group foals were given E coli antiserum (10 micromilligrams) orally between 0 and 8 hours after birth. Serum samples were obtained between 18 and 36 hours after birth, and serum IgG concentration was determined. Foals were monitored for the first 60 days after birth, and causes of disease or death were recorded. RESULTS: Groups did not differ significantly in regard to breed, sex, month of birth, season of birth, age of dams, parity of dams, duration of gestation, or specific gravity of colostrum before suckling. In addition, groups did not differ significantly in regard to mean serum IgG concentration, prevalence of complete or partial failure of passive transfer of immunity, frequency or causes of disease, or frequency of death from infectious causes. CLINICAL IMPLICATIONS: In this group of foals on well-managed farms, administration of E coli antiserum did not alter serum IgG concentrations or morbidity and mortality rates during the first 60 days of life. 相似文献
87.
KL Syrjala SL Roth-Roemer JR Abrams JM Scanlan MK Chapko S Visser JE Sanders 《Canadian Metallurgical Quarterly》1998,16(9):3148-3157
PURPOSE: To describe the prevalence of sexual difficulties in men and women after marrow transplantation (MT), and to define medical, demographic, sexual, and psychologic predictors of sexual dysfunction 3 years after MT. PATIENTS AND METHODS: Four hundred seven adult MT patients were assessed pretransplantation. Survivors repeated measures of psychologic and sexual functioning at 1 and 3 years posttransplantation. RESULTS: Data were analyzed from 102 event-free 3-year survivors who defined themselves as sexually active. Men and women did not differ in sexual satisfaction pretransplantation. At 1 and 3 years posttransplantation, women reported significantly more sexual dysfunction than men. Eighty percent of women and 29% of men reported at least one sexual problem by 3 years after MT. No pretransplantation variables were significant predictors of 3-year sexual satisfaction for women. For men, pretransplantation variables of older age, poorer psychologic function, not being married, and lower sexual satisfaction predicted sexual dissatisfaction at 3 years (R2=.28; P < .001). Women who were more dissatisfied 3 years after MT did not receive hormone replacement therapy (HRT) at 1 -year posttransplantation and were less satisfied at 1 year, but not pretransplantation (R2=.35; P < .001). CONCLUSION: Sexual problems are significant in the lives of MT survivors, particularly for women. Although HRT before 1 year posttransplantation improves sexual function, it does not ensure sexual quality of life. Intervention for women is needed to apply hormonal, mechanical, and behavioral methods to prevent sexual difficulties as early after transplantation as possible. 相似文献
88.
This study investigated the nature of selective attention deficits after severe closed head injury (CHI). Twenty participants with severe CHI (greater than 1 year postinjury) and 20 matched controls completed search and nonsearch visual selective attention tasks under conditions of low (Experiment 1) and high (Experiment 2) target-distractor similarity. In the search situations, participants searched visual displays that contained 1, 4, or 8 items for the targets. In the nonsearch situations, the location of the targets was visually cued with a peripheral arrow. The results revealed that in both the low and high target-distractor similarity search conditions. CHI participants required a longer time than controls to locate and identify the target. In contrast, in the nonsearch condition, CHI participants were able to successfully ignore irrelevant task information when target-distractor similarity was low. However, when target-distractor similarity was high, CHI participants had more difficulty than controls ignoring the irrelevant information. These results suggest that, in comparison to controls, CHI participants may be at a disadvantage in selective attention situations when visual search is required and when the discriminability between targets and distractors is difficult. 相似文献
89.
MK Storch S Piddlesden M Haltia M Iivanainen P Morgan H Lassmann 《Canadian Metallurgical Quarterly》1998,43(4):465-471
Blue light responses in higher plants can be mediated not only by specific blue light receptors, but also by the red/far-red photoreversible phytochrome system. The question of interdependence between these photoreceptors has been debated over many years. The availability of Arabidopsis mutants for the blue light receptor CRY1 and for the two major phytochromes phyA and phyB allows a reinvestigation of this question. The analysis of photocontrol of seed germination, inhibition of hypocotyl growth and anthocyanin accumulation clearly demonstrates that (i) phyA shows a strong control in blue light responses especially at low fluence rates; (ii) phyB mediated induction reactions can be reversed by subsequent blue light irradiations; and (iii) CRY1 mediates blue light controlled inhibition of hypocotyl growth only at fluence rates higher than 5 mumol m-2s-1 and independently of phytochrome A and B. 相似文献
90.
MK Bolla GJ Miller DM Yellon A Evans G Luc JP Cambou D Arveiler F Cambien DS Latchman SE Humphries IN Day 《Canadian Metallurgical Quarterly》1998,13(4):227-235
In 12 depressed inpatients referred for bilateral electroconvulsive therapy (ECT), each patient was titrated at the first treatment session by using an ascending method-of-limits procedure with a step-wise increase in pulse frequency (frequency titration) or train duration (duration titration). At the second treatment session, seizure threshold was redetermined by using the method (frequency or duration titration) not used at the first treatment. Frequency or duration was maintained at the lowest level when the other parameter was titrated. Seizure threshold was significantly lower with duration titration (mean, 90 mC; SD, 27.3) than frequency titration (mean, 114 mC; SD, 35.6; p = 0.03). On average, patients in the duration-titration group required 1.2 (SD, 0.6) subconvulsive stimulations before a seizure was elicited, and patients in the frequency-titration group required 1.7 (SD, 0.9) subconvulsive stimulations before a seizure was elicited, a nonsignificant difference. These findings suggest that to elicit a seizure during ECT, increasing train duration may be slightly more efficient than increasing frequency. Basic and other clinical research findings indicate that increasing pulse width may be an inefficient way to elicit a seizure. Therefore the following sequence in the determination of seizure threshold is worth considering when using dose-titration or related techniques: the train duration should be increased first before increasing pulse frequency, and the decision to increase pulse width should be reserved for patients who do not seize at the maximal duration and frequency settings. Further empiric research is needed to establish the utility of this approach. 相似文献