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141.
Phenolic constituents in dried flowers of aloe vera (Aloe barbadensis) and their in vitro antioxidative capacity 总被引:2,自引:0,他引:2
The dried flowers from Aloe vera (L.) Burm. f. (Aloe barbadensis Mill.) (Asphodelaceae) were analysed by means of HPLC-DAD and HPLC-MS/MS, verifying chlorogenic, caffeic, 5-P-coumaroylquinic, caffeoylshikimic, 5-feruloylquinic, 5-P-CIS-coumaroylquinic, P-coumaric and ferulic acid as well as luteolin, apigenin, quercetin, kaempferol, isoorientin, isovitexin and their 7-O-glucosides, saponarin and lutonarin. On searching for anthranoids in the flower extract, aloe-emodin as well as the glycosylchromone aloeresin B could be identified. Aloin A and B, the laxative principle of the drug Cura?ao-Aloes, are not accumulated in the dried flowers. The polyphenol content of three different batches was 0.73 - 1.01% (+/- 0.05%) and the flavonoid content 0.24 - 0.34% (+/- 0.01%). The hydrophilic antioxidative capacity amounted to 85.7 - 94.9 (+/- 0.5) micromol TEAC/g dried Aloe vera flower and was directly correlated with the polyphenol and flavonoid contents. 相似文献
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143.
Elisabeth Moen ElseLydia Toverud Jan Grund Sissel Brinchmann 《Pharmacy World & Science》1998,20(3):107-112
Pricing and reimbursement of pharmaceuticals are of concern for pharmacists. Different countries have different ways of organising their health care systems. The place for pharmaceuticals within these systems also differ. This article looks into the price and reimbursement systems for medicinal products in Germany, Sweden, the UK and Norway. Various ways of organising the pharmaceutical market emerge. Some existing measures have been in place for a long time while others have been introduced more recently. A common goal for the four countries seems to be the drive to cut costs, and attempts to do this can be directed through various reimbursement systems, by focusing on prices or by influencing the physicians' prescribing behaviour, either through the use of advice or through the use of budgets. It is important for the pharmacists to have indepth knowledge of the price and reimbursement system they have to work within in order to be of full service to their customers. 相似文献
144.
Berthold Pemp Randy H. Kardon Karl Kircher Elisabeth Pernicka Ursula Schmidt-Erfurth Andreas Reitner 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2013,251(7):1841-1848
Background
Automated detection of subtle changes in peripapillary retinal nerve fibre layer thickness (RNFLT) over time using optical coherence tomography (OCT) is limited by inherent image quality before layer segmentation, stabilization of the scan on the peripapillary retina and its precise placement on repeated scans. The present study evaluates image quality and reproducibility of spectral domain (SD)-OCT comparing different rates of automatic real-time tracking (ART).Methods
Peripapillary RNFLT was measured in 40 healthy eyes on six different days using SD-OCT with an eye-tracking system. Image brightness of OCT with unaveraged single frame B-scans was compared to images using ART of 16 B-scans and 100 averaged frames. Short-term and day-to-day reproducibility was evaluated by calculation of intraindividual coefficients of variation (CV) and intraclass correlation coefficients (ICC) for single measurements as well as for seven repeated measurements per study day.Results
Image brightness, short-term reproducibility, and day-to-day reproducibility were significantly improved using ART of 100 frames compared to one and 16 frames. Short-term CV was reduced from 0.94?±?0.31 % and 0.91?±?0.54 % in scans of one and 16 frames to 0.56?±?0.42 % in scans of 100 averaged frames (P?≤?0.003 each). Day-to-day CV was reduced from 0.98?±?0.86 % and 0.78?±?0.56 % to 0.53?±?0.43 % (P?≤?0.022 each). The range of ICC was 0.94 to 0.99. Sample size calculations for detecting changes of RNFLT over time in the range of 2 to 5 μm were performed based on intraindividual variability.Conclusion
Image quality and reproducibility of mean peripapillary RNFLT measurements using SD-OCT is improved by averaging OCT images with eye-tracking compared to unaveraged single frame images. Further improvement is achieved by increasing the amount of frames per measurement, and by averaging values of repeated measurements per session. These strategies may allow a more accurate evaluation of RNFLT reduction in clinical trials observing optic nerve degeneration. 相似文献145.
Lisa Iverach Susan O’Brian Mark Jones Susan Block Michelle Lincoln Elisabeth Harrison Sally Hewat Ross G. Menzies Ann Packman Mark Onslow 《Journal of communication disorders》2010,43(2):120-132
Previous research has not explored the Five Factor Model of personality among adults who stutter. Therefore, the present study investigated the five personality domains of Neuroticism, Extraversion, Openness, Agreeableness and Conscientiousness, as measured by the NEO Five Factor Inventory (NEO-FFI), in a sample of 93 adults seeking speech treatment for stuttering, and compared these scores with normative data from an Australian and a United States sample. Results revealed that NEO-FFI scores for the stuttering group were within the ‘average’ range for all five personality domains. However, adults who stutter were characterized by significantly higher Neuroticism, and significantly lower Agreeableness and Conscientiousness, than normative samples. No significant differences were found between groups on the dimensions of Extraversion and Openness. These results are discussed with reference to the relationship between personality factors among adults who stutter, their directionality, and implications for predicting treatment outcome.Learning outcomes: The reader will be able to: (1) describe the Five Factor Model of personality, including the NEO-FFI personality domains of Extraversion, Neuroticism, Openness, Agreeableness, and Conscientiousness, and (2) discuss differences in NEO-FFI domain scores between adults who stutter and normative samples, and (3) understand the clinical implications of personality profiles in terms of treatment process and outcome for adults who stutter. 相似文献
146.
Clinical pharmacokinetics of oxcarbazepine 总被引:10,自引:0,他引:10
Oxcarbazepine is an antiepileptic drug with a chemical structure similar to carbamazepine, but with different metabolism. Oxcarbazepine is rapidly reduced to 10,11-dihydro-10-hydroxy-carbazepine (monohydroxy derivative, MHD), the clinically relevant metabolite of oxcarbazepine. MHD has (S)-(+)- and the (R)-(-)-enantiomer, but the pharmacokinetics of the racemate are usually reported. The bioavailability of the oral formulation of oxcarbazepine is high (>95%). It is rapidly absorbed after oral administration, reaching peak concentrations within about 1-3 hours after a single dose, whereas the peak of MHD occurs within 4-12 hours. At steady state, the peak of MHD occurs about 2-4 hours after drug intake. The plasma protein binding of MHD is about 40%. Cerebrospinal fluid concentrations of MHD are in the same range as unbound plasma concentrations of MHD. Oxcarbazepine can be transferred significantly through the placenta in humans. Oxcarbazepine and MHD exhibit linear pharmaco-kinetics and no autoinduction occurs. Elimination half-lives in healthy volunteers are 1-5 hours for oxcarbazepine and 7-20 hours for MHD. Longer and shorter elimination half-lives have been reported in elderly volunteers and children, respectively. Mild to moderate hepatic impairment does not appear to affect MHD pharmacokinetics. Renal impairment affects the pharmacokinetics of oxcarbazepine and MHD. The interaction potential of oxcarbazepine is relatively low. However, enzyme-inducing antiepileptic drugs such as phenytoin, phenobarbital or carbamazepine can reduce slightly the concentrations of MHD. Verapamil may moderately decrease MHD concentrations, but this effect is probably without clinical relevance. The influence of oxcarbazepine on other antiepileptic drugs is not clinically relevant in most cases. However, oxcarbazepine appears to increase concentrations of phenytoin and to decrease trough concentrations of lamotrigine and topiramate. Oxcarbazepine lowers concentrations of ethinylestra-diol and levonorgestrel, and women treated with oxcarbazepine should consider additional contraceptive measures. Due to the absent or lower enzyme-inducing effect of oxcarbazepine, switching from carbamazepine to oxcarbazepine can result in increased serum concentrations of comedication, sometimes associated with adverse effects. The effect of oxcarbazepine appears to be related to dose and to serum concentrations of MHD. In general, daily fluctuations of MHD concentration are relatively slight, smaller than would be expected from the elimination half-life of MHD. However, relatively high fluctuations can be observed in individual patients. Therapeutic monitoring may help to decide whether adverse effects are dependent on MHD concentrations. A mean therapeutic range of 15-35 mg/L for MHD seems to be appropriate. However, more systematic studies exploring the concentration-effect relationship are required. 相似文献
147.
Peter M. Kaskan Mark A. Nicholas Aaron M. Dean Elisabeth A. Murray 《The Journal of neuroscience》2022,42(49):9242
The neural bases of attention, a set of neural processes that promote behavioral selection, is a subject of intense investigation. In humans, rewarded cues influence attention, even when those cues are irrelevant to the current task. Because the amygdala plays a role in reward processing, and the activity of amygdala neurons has been linked to spatial attention, we reasoned that the amygdala may be essential for attending to rewarded images. To test this possibility, we used an attentional capture task, which provides a quantitative measure of attentional bias. Specifically, we compared reaction times (RTs) of adult male rhesus monkeys with bilateral amygdala lesions and unoperated controls as they made a saccade away from a high- or low-value rewarded image to a peripheral target. We predicted that: (1) RTs will be longer for high- compared with low-value images, revealing attentional capture by rewarded stimuli; and (2) relative to controls, monkeys with amygdala lesions would exhibit shorter RT for high-value images. For comparison, we assessed the same groups of monkeys for attentional capture by images of predators and conspecifics, categories thought to have innate biological value. In performing the attentional capture task, all monkeys were slowed more by high-value relative to low-value rewarded images. Contrary to our prediction, amygdala lesions failed to disrupt this effect. When presented with images of predators and conspecifics, however, monkeys with amygdala lesions showed significantly diminished attentional capture relative to controls. Thus, separate neural pathways are responsible for allocating attention to stimuli with learned versus innate value.SIGNIFICANCE STATEMENT Valuable objects attract attention. The amygdala is known to contribute to reward processing and the encoding of object reward value. We therefore examined whether the amygdala is necessary for allocating attention to rewarded objects. For comparison, we assessed the amygdala''s contribution to attending to objects with innate biological value: predators and conspecifics. We found that the macaque amygdala is necessary for directing attention to images with innate biological value, but not for directing attention to recently learned reward-predictive images. These findings indicate that the amygdala makes selective contributions to attending to valuable objects. The data are relevant to mental health disorders, such as social anxiety disorders and small animal phobias, that arise from biased attention to select categories of objects. 相似文献
148.
149.
150.
Mahala Livingston Pavitra Pillay Siphosenkosi Gift Zulu Leiv Sandvik Jane Dene Kvalsvig Silindile Gagai Hashini Nilushika Galappaththi-Arachchige Elisabeth Kleppa Patricia Ndhlovu Birgitte Vennervald Svein Gunnar Gundersen Myra Taylor Eyrun F. Kjetland 《The American journal of tropical medicine and hygiene》2021,104(6):2055