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1.
Lysophosphatidylcholine (LPC) possesses excellent oil‐in‐water emulsifying properties and health benefits. The objective of this study was to produce an LPC‐enriched fraction from lysolecithin generated during enzymatic degumming of crude canola oil. Three alcohols (methanol, ethanol and isopropanol) were evaluated for their effectiveness at enriching LPC. A 3 × 3 full factorial design was employed to study the effects of two processing parameters (temperature and alcohol/lysolecithin ratio) on three responses (yield and LPC concentration of alcohol soluble fraction, and LPC recovery) with the most effective alcohol. Ethanol was found to be the best solvent to enrich LPC in lysolecithin. An ethanol soluble fraction with more than 50 % LPC was produced. Quadratic models with R2 > 0.9 were developed to describe the relationship between the processing parameters and the responses in the 3 × 3 full factorial experiment. Both ethanol soluble fraction yield and LPC recovery increased with increasing temperature and ethanol/lysolecithin ratio. LPC concentration in the ethanol soluble fraction was enhanced with decreasing temperature and ethanol/lysolecithin ratio. According to the analysis, ethanol soluble fractions with LPC concentration higher than 66 % could be obtained at temperatures of 0–40 °C and an ethanol/lysolecithin ratio of 2:1 (v/w).  相似文献   
2.
Policosanols (PCs) are a group of long chain aliphatic alcohols that have been reported to have low-density lipoprotein (LDL) cholesterol-lowering properties. Wheat is a good source of these compounds. This study examined the effect of solvent type and temperature on extract yields and PC content and composition in the extracts. Wheat germ, straw and bran samples were extracted with petroleum ether, chloroform, n-hexane and ethanol at various temperatures ranging from 80 to 125 °C.  相似文献   
3.
Previous work from this laboratory has demonstrated that monosynaptic inputs from the brachium of the inferior colliculus (BIC) to the medial subdivision of the medial geniculate nucleus (mMG) strengthen as a result of associative conditioning with an acoustic conditioned stimulus (i.e., fear conditioning). One model that has been proposed to underlie certain types of neuronal plasticity involves the recruitment of N-methyl-D-aspartic acid (NMDA)-type glutamate receptors. The purpose of the present study was to examine the relative contributions of glutamatergic NMDA and non-NMDA receptors to synaptic transmission within this pathway. Individual contributions of the specific receptor types were assessed through the use of 2-amino-5-phosphonovaleric acid (AP5), a selective NMDA receptor antagonist, and 6-cyano-5-nitroquinoxaline-2,3-dione (CNQX), a non-NMDA receptor antagonist. Bipolar stimulating electrodes were stereotaxically implanted in BIC and recording electrodes (attached to dual 32-gauge cannulae for delivery of drug) were positioned in mMG of New Zealand albino rabbits. Single pulses (150 micros, 100-350 microA) delivered to BIC resulted in short-latency (<4 ms) responses in mMG. BIC-evoked single-unit activity was recorded from mMG before, during, and at several intervals after injection of AP5, CNQX, and/or artificial cerebrospinal fluid (ACSF). Injection of either AP5 or CNQX, but not ACSF, significantly attenuated the short-latency BIC-evoked responses in the vast majority of cells tested. These findings suggest that the monosynaptic pathway from BIC to mMG is glutamatergic and that this pathway frequently employs NMDA-type receptors during electrically stimulated synaptic transmission. Due to the NMDA receptors' proposed role in plasticity (e.g., long-term potentiation), these results may have implications for understanding the mechanisms of synaptic plasticity observed at this synapse during associative learning.  相似文献   
4.
OBJECTIVES: To create a profile of individuals nonadherent to their medications in an age-stratified sample (ages 34-84) of community-dwelling rheumatoid arthritis patients. The relative contributions of age, cognitive function, disability, emotional state, lifestyle, and beliefs about illness to nonadherence were assessed. DESIGN: A direct observation approach was used in conjunction with structural equation modeling. All participants were administered a preliminary assessment battery. Medications were then transferred to vials with microelectronic caps that recorded medication events for all medications for the next 4 weeks. PARTICIPANTS AND SETTING: A volunteer sample of 121 community-dwelling rheumatoid arthritis (RA) patients were recruited from newspaper ads, posters, and via informal physician contact from private rheumatology practices in Atlanta and Athens, Georgia. Written verification of the RA diagnosis and a disease severity rating were obtained from personal physicians before patients were enrolled in the study. Patients were tested in a private physician's office, and their medication adherence was monitored electronically for a month in their every-day work and home settings. MEASUREMENTS AND RESULTS: Structural equation modeling techniques were used to develop a model of adherence behavior. Cognitive and psychosocial measures were used to construct latent variables to predict adherence errors. The model of medication adherence explained 39% of the variance in adherence errors. The model demonstrated that older adults made the fewest adherence errors, and middle-aged adults made the most. A busy lifestyle, age, and cognitive deficits predicted nonadherence, whereas coping with arthritis-related moods predicted adherence. Illness severity, medication load, and physical function did not predict adherence errors. Omission of medication accounted for nearly all errors. CONCLUSION: Despite strong evidence for normal, age-related cognitive decline in this sample, older adults had sufficient cognitive function to manage medications. A busy lifestyle and middle age were more determinant of who was at risk of nonadherence than beliefs about medication or illness. Thus, practicing physicians should not assume that older adults have insufficient cognitive resources to manage medications and that they will be the most likely to make adherence errors. Very busy middle-aged adults seem to be at the greatest risk of managing medications improperly.  相似文献   
5.
Original studies leading to the gravitational model of pulmonary blood flow and contemporary studies showing gravity-independent perfusion differ in the recent use of laboratory animals instead of humans. We explored the distribution of pulmonary blood flow in baboons because their anatomy, serial distribution of vascular resistances, and hemodynamic responses to hypoxia are similar to those of humans. Four baboons were anesthetized with ketamine, intubated, and mechanically ventilated. Different colors of fluorescent microspheres were given intravenously while the animals were in the supine, prone, upright (repeated), and head-down (repeated) postures. The animals were killed, and their lungs were excised, dried, and diced into approximately 2-cm3 pieces with the spatial coordinates recorded for each piece. Regional blood flow was determined for each posture from the fluorescent signals of each piece. Perfusion heterogeneity was greatest in the upright posture and least when prone. Using multiple-stepwise regression, we estimate that 7, 5, and 25% of perfusion heterogeneity is due to gravity in the supine, prone, and upright postures, respectively. Although important, gravity is not the predominant determinant of pulmonary perfusion heterogeneity in upright primates. Because of anatomic similarities, the same may be true for humans.  相似文献   
6.
Immunocytochemical examination for mitochondrial protein and cytochrome oxidase was performed to demonstrate oncocytes in normal adenohypophysis obtained from 28 patients of various age. A small number of solitary large epithelial cells showed intense cytoplasmic granular immunoreactivities for mitochondrial protein and cytochrome oxidase. The proportions of the cells positive for the former and the latter ranged from 0% to 5.9% (mean+/-SD; 1.5+/-1.7%) and from 0% to 4.9% (1.4+/-1.6%), respectively. These cells were either absent or extremely rare in young patients (under 10 years) but tended to increase in number with age (P < 0.0001). On the other hand, the mirror section technique showed that most of these cells were negative for adenohypophysial hormones, but a few of them were faintly positive for: alpha-subunit (8.0%), beta-subunits of follicle-stimulating hormone (4.8%), luteinizing hormone (2.5%), thyroid-stimulating hormone (1.0%), and growth hormone (0.5%), and were negative for prolactin and adrenocorticotropic hormone. We considered that these cells represent oncocytes that exist in varying numbers in normal adenohypophysis. It was suggested that oncocytes in normal adenohypophysis share various common features with tumorous oncocytes of pituitary oncocytomas.  相似文献   
7.
Two samples of the marine sponge Stylissa carteri collected in Indonesia yielded two new bromopyrrole alkaloids: debromostevensine (1) and debromohymenin (2), as well as nine other known congeners (3-11). The structures of the new compounds were unambiguously established on the basis of their NMR and mass spectra.  相似文献   
8.
Supercritical carbon dioxide (SC–CO2) fractionation technique was evaluated as an alternative process for reducing the free‐fatty‐acid (FFA) content and minimizing the phytosterol loss of rice bran oil (RBO) during the process. The effects of pressure (20.5 to 32.0 MPa) and temperature (45 to 80 °C) for isothermal operation of the column on the composition of the resultant fractions were examined. Low‐pressure and high‐temperature conditions were found to be favorable for minimizing triglycerides (TG) and phytosterol losses during the FFA removal from crude RBO. Rice bran oil fractions with < 1% FFA, about 95% TG, and 0.35% free sterol with 1.8% oryzanol content could be obtained utilizing the described SC–CO2 fractionation technique.  相似文献   
9.
This article reviews issues concerning the training and credentialing of vascular surgeons in the use of endovascular techniques in the peripheral vascular system. These guidelines update a prior document that was published in 1993. They have been rewritten to accommodate the rapid evolution that has occurred in the field and to provide the appropriate requirements that a vascular surgeon should fulfill to be competent in the basic skills needed to safely and effectively perform all presently accepted diagnostic and therapeutic endovascular procedures.  相似文献   
10.
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