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131.
Pandanus conoideus fruit contained 19.4% by dry weight of red fat. Major fatty acids contained in the fat were oleic (67.6% of the total fatty acids), palmitic (18.7%) and linoleic (7.6%) acids. The fat had an unusually high level of free fatty acid (90.0%) which may have resulted from the action of fat splitting enzymes. 相似文献
132.
Michelle L. Baack Susan E. Puumala Stephen E. Messier Deborah K. Pritchett William S. Harris 《Lipids》2016,51(4):423-433
Docosahexaenoic acid (DHA) is an essential fatty acid (FA) important for health and neurodevelopment. Premature infants are at risk of DHA deficiency and circulating levels directly correlate with health outcomes. Most supplementation strategies have focused on increasing DHA content in mother's milk or infant formula. However, extremely premature infants may not reach full feedings for weeks and commercially available parenteral lipid emulsions do not contain preformed DHA, so blood levels decline rapidly after birth. Our objective was to develop a DHA supplementation strategy to overcome these barriers. This double‐blind, randomized, controlled trial determined feasibility, tolerability and efficacy of daily enteral DHA supplementation (50 mg/day) in addition to standard nutrition for preterm infants (24–34 weeks gestational age) beginning in the first week of life. Blood FA levels were analyzed at baseline, full feedings and near discharge in DHA (n = 31) or placebo supplemented (n = 29) preterm infants. Term peers (n = 30) were analyzed for comparison. Preterm infants had lower baseline DHA levels (p < 0.0001). Those receiving DHA had a progressive increase in circulating DHA over time (from 3.33 to 4.09 wt% or 2.88 to 3.55 mol%, p < 0.0001) while placebo‐supplemented infants (receiving standard neonatal nutrition) had no increase over time (from 3.35 to 3.32 wt% or 2.91 to 2.87 mol%). Although levels increased with additional DHA supplementation, preterm infants still had lower blood DHA levels than term peers (4.97 wt% or 4.31 mol%) at discharge (p = 0.0002). No differences in adverse events were observed between the groups. Overall, daily enteral DHA supplementation is feasible and alleviates deficiency in premature infants. 相似文献
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134.
Plant sources of omega-3 fatty acids (FA) are needed that can materially raise tissue levels of long-chain omega-3 FA [i.e.,
eicosapentaenoic acid (EPA; 20:5n-3) and docosahexaenoic acid (DHA; 20:6n-3)]. Stearidonic acid (SDA; 18:4n-3) is the delta-6
desaturase product of alpha-linolenic acid (ALA; 18:3n-3), and when fed to humans, increases red blood cell (RBC) content
of EPA to a greater extent than does ALA. This study was undertaken to determine the dose-dependence and time course of the
increase in the EPA and DHA content of the heart and RBC in dogs. Adult male Beagles were fed 21, 64, or 193 mg/kg of SDA
in in their food daily for up to 12 weeks. Positive and negative controls were given EPA (43 mg/kg) or high oleic acid sunflower
oil, respectively. The baseline EPA content of RBC was 0.38 ± 0.03% which increased (P < 0.01) in a dose-dependent manner, with the high dose of SDA and EPA achieving levels of 1.33 ± 0.26 and 1.55. ± 0.28%,
respectively. In the heart, the content of EPA rose from 0.06 ± 0.01 to 1.24 ± 0.22% in the EPA group and to 0.81 ± 0.32%
in the high SDA group (both P < 0.01). In both tissues, DHA did not change. Compared to dietary EPA, SDA was 20–23% as efficient in raising tissue EPA
levels. In conclusion, SDA supplementation increased the EPA content of RBC and heart and may have utility as a plant-based
source of omega-3 FA. 相似文献
135.
The objective of these studies was to determine if methyl xanthines can be used to alter milk production or composition in ruminants by enhancing adipose tissue mobilization. Three trials were conducted, one with intravenous caffeine infusions, one with intramuscular caffeine injections, and one with intramuscular injections of 3-isobutyl 1-methyl xanthine. Results indicate that: 1) continuous intravenous infusions of caffeine (720 mg/d) may reverse the milk fat depression of intravenously infused glucose in dairy goats; 2) intramuscular injections of caffeine (200 mg twice daily) do not reverse the milk fat-depressing effects of pelleted dairy goat diets during the 4th mo of lactation; and 3) intramuscular injections of 3-isobutyl 1-methyl xanthine (50 mg twice daily) do not consistently affect milk production of early lactation dairy goats. 相似文献
136.
Gema Casal Xavier Monteys John Hedley Paul Harris Conor Cahalane Tim McCarthy 《International journal of remote sensing》2019,40(8):2855-2879
Bathymetry estimated from optical satellite imagery has been increasingly implemented as an alternative to traditional bathymetric survey techniques. The availability of new sensors such as Sentinel-2 with improved spatial and temporal resolution, in comparison with previous optical sensors, offers innovative capabilities for bathymetry derivation. This study presents an assessment of the fit between satellite data and the underlying models in the most widely used empirical algorithms: the linear band model and the log-transformed band ratio model using Sentinel-2A data. Both models were tested in two study areas of the Irish coast with different morphological and environmental conditions. Results showed that the linear band model fitted better than the log-transformed band ratio model providing coefficient of determination values, R2, between 0.83 and 0.88 (0 m–10 m) for the five images considered in the study. The closest fit was found in the depth range 2 m–6 m. Atmospheric correction, bottom type influence, and water column conditions proved to be key factors in the bathymetric derivation using these satellite datasets. 相似文献
137.
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139.
S Abdi LD Traber DN Herndon CS Rogers DL Traber 《Canadian Metallurgical Quarterly》1995,293(4):475-481
We studied the effects of ibuprofen on bronchial blood flow and myocardial function after inhalation injury. Sheep (n = 12) were chronically instrumented with cardiovascular and pulmonary catheters. After 5 days of recovery period, baseline data were collected and the sheep were divided into two groups. Group S (n = 6) were insufflated with 48 breaths of cotton smoke; while group I (n = 6) were pretreated with ibuprofen (12mg/kg bolus followed by 3 mg/kg/h continuous infusion for 24 h) and challenged with the same dose of smoke. All the animals were studied for 24h. Bronchial blood flow increased significantly in both groups throughout the experimental period; while stroke volume as well as right and left ventricular stroke work indices of both groups were significantly decreased (group I worse than group S) in the second half of the experimental period. These data suggest that vasodilatory prostaglandins do not play a major role in the bronchial vascular response to smoke inhalation injury and myocardial depression seen post injury is worse in animals treated with ibuprofen. 相似文献
140.
Extracellular recordings were made from the magnocellular neurones of the red nucleus (mRN) in anaesthetised cats. A study was made of the effects of selective excitatory amino acid receptor antagonists on excitatory monosynaptic responses evoked from the sensorimotor cortex (SMC) and cerebellar interpositus nucleus (IPN). Iontophoretically applied CNQX and NBQX antagonised both SMC and IPN responses whereas, D-AP5 inhibited the SMC response but was ineffective to the IPN. At currents that selectively antagonised NMDA responses, CPPene had no effect on either SMC or IPN responses. 7-chlorokynurenate inhibited both SMC and IPN responses but required currents that antagonised both AMPA and NMDA responses and was therefore acting in a non-selective manner. Iontophoretically applied glycine was inhibitory to both agonist and synaptic responses, whilst D-serine potentiated NMDA responses but did not enhance monosynaptic responses of the SMC. However in the presence of either 7-chlorokynurenate or high currents of CNQX that reduced the SMC synaptic activation of the mRN neurones, D-serine attenuated the inhibitory action of these antagonists. It is concluded that monosynaptic responses from the SMC are mediated by both NMDA and non-NMDA receptors whereas the monosynaptic responses evoked from the IPN are mediated only by non-NMDA receptors. The lack of effect of CPPene is consistent with the postulate that two NMDA receptor subtypes are present on mRN neurones. 相似文献