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191.
Carmel Bilu Haim Einat Katy Tal-Krivisky Joseph Mizrahi Vicktoria Vishnevskia-Dai Galila Agam 《Chronobiology international》2019,36(7):919-926
Despite the common use of bright light exposure for treatment of seasonal affective disorder (SAD), the underlying biology of the therapeutic effect is not clear. Moreover, there is a debate regarding the most efficacious wavelength of light for treatment. Whereas according to the traditional approach full-spectrum light is used, recent studies suggest that the critical wavelengths are within the range of blue light (460 and 484 nm). Our previous work shows that when diurnal rodents are maintained under short photoperiod they develop depression- and anxiety-like behavioral phenotype that is ameliorated by treatment with wide-spectrum bright light exposure (2500 lux at the cage, 5000 K). Our current study compares the effect of bright wide-spectrum (3,000 lux, wavelength 420- 780 nm, 5487 K), blue (1,300 lux, wavelength 420-530 nm) and red light (1,300 lux, wavelength range 600-780 nm) exposure in the fat sand rat (Psammomys Obesus) model of SAD. We report results of experiments with six groups of sand rats that were kept under various photoperiods and light treatments, and subjected to behavioral tests related to emotions: forced swim test, elevated plus maze and social interactions. Exposure to either intense wide-spectrum white light or to blue light equally ameliorated depression-like behavior whereas red light had no effect. Bright wide-spectrum white light treatment had no effect on animals maintained under neutral photoperiod, meaning that light exposure was only effective in the pathological-like state. The resemblance between the effects of bright white light and blue light suggests that intrinsically photosensitive retinal ganglion cells (ipRGCs) are involved in the underlying biology of SAD and light therapy. 相似文献
192.
Predictive genetic testing may confront those affected with difficult life situations that they have not experienced before. These life situations may be interpreted as ‘absurd’. In this paper we present a case study of a predictive test situation, showing the perspective of a woman going through the process of deciding for or against taking the test, and struggling with feelings of alienation. To interpret her experiences, we refer to the concept of absurdity, developed by the French Philosopher Albert Camus. Camus' writings on absurdity appear to resonate with patients' stories when they talk about their body and experiences of illness. In this paper we draw on Camus' philosophical essay ‘The Myth of Sisyphus’ (1942), and compare the absurd experiences of Sisyphus with the interviewee's story. This comparison opens up a field of ethical reflection. We demonstrate that Camus' concept of absurdity offers a new and promising approach to understanding the fragility of patients' situations, especially in the field of predictive testing. We show that people affected might find new meaning through narratives that help them to reconstruct the absurd without totally overcoming it. In conclusion, we will draw out some normative consequences of our narrative approach. 相似文献
193.
《Biologicals》2014,42(4):205-217
Approximately 70% of animal use is utilized to demonstrate quality control of vaccines. Especially rabies vaccine potency testing, using the NIH challenge test, involves objections in terms of scientific relevance, animal welfare concern and costs. Several 3R models have been proposed to refine, reduce or replace this test. Some are formally incorporated into regulatory requirements, but actual regulatory acceptance and use by industry lags behind, raising the question concerning which factors influence this process. This question is answered by a combination of literature review, interviews and a survey among 50 rabies vaccine experts. The findings are analyzed using the multilevel perspective on technology transition, which distinguishes 3 levels of factors influencing innovation acceptance. At the micro level (where 3R models are developed and validated) the dis-advantages of, and fractional experience with, 3R models, scarce data sharing and demanding validation processes exist. The meso level (existing regulatory regime) encloses the barriers of the ‘gold standard’, the lack of harmonization and the driving force of legislation stimulating 3Rs use. The macro level (the societal context) combines risk aversion and increased concern for animal welfare. Regulatory acceptance and use of 3R models requires dedicated stakeholder communication, cooperation and coordination at all three levels. 相似文献
194.
Robert E. Jefferson Duyoung Min Karolina Corin Jing Yang Wang James U. Bowie 《Journal of molecular biology》2018,430(4):424-437
Protein folding is a fundamental life process with many implications throughout biology and medicine. Consequently, there have been enormous efforts to understand how proteins fold. Almost all of this effort has focused on water-soluble proteins, however, leaving membrane proteins largely wandering in the wilderness. The neglect has occurred not because membrane proteins are unimportant but rather because they present many theoretical and technical complications. Indeed, quantitative membrane protein folding studies are generally restricted to a handful of well-behaved proteins. Single-molecule methods may greatly alter this picture, however, because the ability to work at or near infinite dilution removes aggregation problems, one of the main technical challenges of membrane protein folding studies. 相似文献
195.
In this paper existence and stability of subharmonic solutions of the Volterra-Verhulst equations with a periodic coefficient are analyzed by the method of Urabe. The study supports the view that the observed 4- and 10-yr cycles of prey-predator systems are due to seasonal fluctuations.AMS(MOS) classification: 92A15, 34C25, 34A50 相似文献
196.
Background: Traditional Chinese medicine (TCM) has been attracting lots of attentions from various disciplines recently. However, TCM is still mysterious because of its unique philosophy and theoretical thinking. Due to the lack of high quality data, understanding TCM thoroughly faces critical challenges. In this study, we introduce the Zhou Archive, a large-scale database of expert-specific Electronic Medical Records containing information about 73,000+ visits to one TCM doctor for over 35 years. Covering the full spectrum of diagnosis-treatment model behind TCM practice, the archive provides an opportunity to understand TCM from the data-driven perspective. Methods: Processing the text data in the archive via a series of data processing steps, we transformed the semi-structured EMRs in the archive to a well-structured feature table. Based on the structured feature table obtained, a series of statistical analyses are implemented to learn principles of TCM clinical practice from the archive, including correlation analysis, enrichment analysis, embedding analysis and association pattern discovery. Results: A structured feature table of 14,000+ features is generated at the end of the proposed data processing procedure, with a feature codebook, a term dictionary and a term-feature map as byproducts. Statistical analysis of the feature table reveals underlying principles about the diagnosis-treatment model of TCM, helping us better understand the TDM practice from a data-driven perspective. Conclusion: Expert-specific EMRs provide opportunities to understand TCM from the data-driven perspective. Taking advantage of recent progresses on NLP for Chinese, we can process a large number of TCM EMRs efficiently to gain insights via statistical analysis. 相似文献
197.
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199.
目的 本研究旨在观察不同持续时间的模拟失重对大鼠抑郁样行为和海马超氧化物歧化酶(SOD)和过氧化氢酶(CAT)的影响,以探究其影响及可能的作用机制。方法 采用后肢悬挂(HLS)尾吊法模拟大鼠失重状态。将大鼠分为对照组和不同模拟失重时间尾吊组(尾吊时长分别为1、2、3、4周)。采用旷场实验(OFT)、新物体识别实验(NORT)、强迫游泳实验(FST)观察大鼠抑郁样行为,采用酶联免疫吸附试验(ELISA)法测定海马SOD和CAT活性。结果 OFT结果显示,与对照组相比,HLS不同时间大鼠的僵滞时间增加(P<0.05,P<0.01)。在NORT中,与对照组相比,HLS不同时间大鼠对新物体的探索潜伏期增加,探索次数和时间减少(P<0.05,P<0.01)。在FST中,与对照组相比,HLS不同时间大鼠在FST中的不动时间增加,攀爬次数减少(P<0.05,P<0.01)。与对照组相比,HLS不同时间组大鼠海马组织中SOD和CAT水平均下降(P<0.05,P<0.01)。结论 短时间或长时间的失重都会导致大鼠产生类抑郁样行为。 相似文献
200.
John F. Neumaier Ross A. McDevitt† Ilham Y. Polis‡ Loren H. Parsons‡ 《Journal of neurochemistry》2009,111(1):217-227
This study investigated how different stages of cocaine self-administration in rats affect the expression of two serotonin receptors in dorsal and ventral striatum, the 5-HT1B and 5-HT6 subtypes, which have both been implicated in mediating some aspects of cocaine-related behaviors. In the first experiment, rats were trained to work for saccharin (oral) or cocaine (i.v.) reinforcers. We found that continuous access to cocaine for 23 days did not change the level of 5-HT1B mRNA expression compared to control animals receiving saccharin. However, a single cocaine session, given either by self-administration or non-contingently, increased 5-HT1B mRNA in dorsal striatum, whereas forced abstinence for two weeks after cocaine reduced 5-HT1B mRNA expression in the same subregion. 5-HT6 mRNA was not changed by any of these treatments. A follow-up experiment investigated the effects of limited versus extended access to cocaine as well as forced abstinence, and we found that 14 days of forced abstinence significantly reduced 5-HT1B mRNA throughout the dorsal and ventral striatum compared to no withdrawal. These results suggest that the influence of 5-HT1B receptors in striatal projection neurons may be increased during cocaine acquisition and reduced after forced abstinence and may therefore be targets for pharmacological intervention in addiction. 相似文献