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91.
基于PAE编码系统构建的半自然条件下长江江豚行为谱   总被引:2,自引:0,他引:2  
识别和编制动物行为谱是深入研究动物行为及其与环境复杂关系的基础和前提。本研究于2013年8月至2014年4月以栖息在铜陵淡水豚国家级自然保护区半自然水域的8头长江江豚为研究对象,采用焦点动物取样法和随机动物取样法观察记录了动物行为发生的过程、内容和环境,并以"姿势—动作—环境"(posture-act-environment,PAE)为轴心,以行为的功能为依据,构建了长江江豚的PAE行为谱。共分辨记录了半自然水域长江江豚的8种姿势、33种动作和46种行为,并定性描述了不同行为出现频率与年龄组、性别的关系。该行为谱综合了姿势和环境信息,有助于进一步研究长江江豚的生态与行为、促进长江江豚的保护。  相似文献   
92.
In recent years, circular RNAs (circRNAs) have been identified to be essential regulators of various human cancers. However, knowledge of the functions of circRNAs in prostate cancer remains very limited. The correlation between circABCC4 and human cancer is largely unknown. This study aims to investigate the biological functions of circABCC4 in prostate cancer progression and illustrate the underlying mechanism. We found that circABCC4 was remarkably up‐regulated in prostate cancer tissues and cell lines and promoted FOXP4 expression by sponging miR‐1182 in prostate cancer cells. CircABCC4 knockdown markedly suppressed prostate cancer cell proliferation, cell‐cycle progression, migration and invasion in vitro. Furthermore, silencing of the circRNA also delayed tumor growth in vivo. Taken together, our findings indicated that circABCC4 facilitates the malignant behaviour of prostate cancer by promoting FOXP4 expression through sponging of miR‐1182. The circABCC4–miR‐1182‐FOXP4 regulatory loop may be a promising therapeutic target for prostate cancer intervention.  相似文献   
93.
安冉  刘斌  徐艺玫  黎歌  廖力夫 《兽类学报》2015,35(2):170-175
本文通过红外线照相的方法,对发育期的林睡鼠幼鼠进行室内活动规律及行为观察,为充分了解林睡鼠越冬前的能量储备形式提供饲养参考。将鼠密度监测仪固定在饲养笼具上方,24h连续拍照,采集和分析6-9月年龄在10周内的幼鼠各种活动数据。结果显示:幼鼠一天中超过70%的时间都在窝内度过,大部分时间都蜷缩成一团少有动作;在窝外活动时间多在玩耍,如攀爬笼架。用于进食和饮水的时间不超过全天的2%。林睡鼠幼鼠主要活动时间在21:00-07:00,活动高峰在21:00-03:00之间。幼鼠出生3周后开始出窝活动,哺乳期30d后开始采食,5周后幼鼠有交配玩耍行为。随着日龄的增长,活动高峰从23:00提前到21:00,活动时间也逐渐延长,但9周龄后活动时间逐渐缩短,幼鼠的饮水进食时间与其活动的时间长短较为一致。10周体重可达成年体重的70%。研究表明,林睡鼠在夏秋季节基本是昼伏夜出动物。光照是影响其在外活动的重要因素之一。幼鼠6周后所需的饲料和水量大于成年林睡鼠,在此期间要注意饲料和水的补充。  相似文献   
94.
Using immunocytochemistry, morphometry and electron microscopy, we have investigated the distribution and characteristics of CD15-immunoreactive (IR) neurons in the guinea pig retina. In the present study, two types of amacrine cells, including interplexiform cells in the inner nuclear layer (INL) and some cells in the ganglion cell layer (GCL), were labeled with anti-CD15 antisera. Type 1 amacrine cells had large somata located in the INL, with long and branched processes ramifying mainly in strata 4 and 5 of the inner plexiform layer (IPL). Somata of type 2 cells had smaller diameters, and were also located in the INL. Their processes stratified in stratum 1. The densities of type I and type 2 amacrine cells increased from 152.8+/-36.7/mm2 and 160.6+/-61.7/mm2 in the peripheral retina, to 404.3+/-41.5/mm2 and 552.2+/-72.2/mm2 in the central retina, respectively. Cells in the GCL exhibiting CD15 immunoreactivity were rarely observed. Colocalization experiments, using consecutive semi-thin sections, demonstrated that these CD15-IR amacrine cells exhibited gamma-aminobutyric acid (GABA) immunoreactivity. In addition, the processes of the type 1 cells formed one member of the postsynaptic dyads that are formed in the axon terminals of rod bipolar cells. Most of these processes made reciprocal synapses back to the axon terminals of the rod bipolar cells. Thus, CD15-IR amacrine cells constitute a subpopulation of GABAergic amacrine cells in the guinea pig retina, and the type 1 cells among them provide the inhibitory input to rod bipolar cells.  相似文献   
95.
Lipid peroxidation has been implicated in a variety of pathophysiological processes, including inflammation, atherogenesis, neurodegeneration, and the ageing process. Phospholipid hydroperoxide glutathione peroxidase (GPX4) is the only major antioxidant enzyme known to directly reduce phospholipid hydroperoxides within membranes and lipoproteins, acting in conjunction with alpha tocopherol (vitamin E) to inhibit lipid peroxidation. Here we describe the generation and characterization of GPX4-deficient mice by targeted disruption of the murine Gpx4 locus through homologous recombination in embryonic stem cells. Gpx4(-/-) embryos die in utero by midgestation (E7.5) and are associated with a lack of normal structural compartmentalization. Gpx4(+/-) mice display reduced levels of Gpx4 mRNA and protein in various tissues. Interestingly, cell lines derived from Gpx4(+/-) mice are markedly sensitive to inducers of oxidative stress, including gamma-irradiation, paraquat, tert-butylhydroperoxide, and hydrogen peroxide, as compared to cell lines derived from wild-type control littermates. Gpx4(+/-) mice also display reduced survival in response to gamma-irradiation. Our observations establish GPX4 as an essential antioxidant enzyme in mice and suggest that it performs broad functions as a component of the mammalian antioxidant network.  相似文献   
96.
Herein n-, iso- and anteiso-series of very-long-chained (VLC) alkanes (C21–C35), fatty acid benzyl esters (FABEs; C20–C32), and 2-alkanones (C23–C35) were identified in the wax of Primula veris L. and P. acaulis (L.) L. (Primulaceae). For the very first time in a sample of natural origin, the presence of iso- and anteiso-VLC FABEs and 2-alkanones was unequivocally confirmed by synthetic work, derivatization, and NMR. It should be noted that the studied species produced unusually high amounts of branched wax constituents (e. g., >50 % of 2-alkanones were branched isomers). The domination of iso-isomers, probably biosynthesized from leucine-derived starters, is a unique feature in the Plant Kingdom. The plant organ distribution of these VLC compounds in P. acaulis samples (different habitats and phenological phases) pointed to their possible ecological value. This was supported by a eutectic behavior of binary blends of FABEs and alkanes, as well as by high UV-C absorption by FABEs.  相似文献   
97.
98.
Psychological stress is one of the factors associated with human cardiovascular disease. Here, we demonstrate that acute perceived stress impairs the natural capacity of heart regeneration in zebrafish. Beside physical and chemical disturbances, intermittent crowding triggered an increase in cortisol secretion and blocked the replacement of fibrotic tissue with new myocardium. Pharmacological simulation of stress by pulse treatment with dexamethasone/adrenaline reproduced the regeneration failure, while inhibition of the stress response with anxiolytic drugs partially rescued the regenerative process. Impaired heart regeneration in stressed animals was associated with a reduced cardiomyocyte proliferation and with the downregulation of several genes, including igfbp1b, a modulator of IGF signalling. Notably, daily stress induced a decrease in Igf1r phosphorylation. As cardiomyocyte proliferation was decreased in response to IGF-1 receptor inhibition, we propose that the stress-induced cardiac regenerative failure is partially caused by the attenuation of IGF signalling. These findings indicate that the natural regenerative ability of the zebrafish heart is vulnerable to the systemic paracrine stress response.  相似文献   
99.
The authors present what they believe to be the first recorded case of a lumbar hernia following latissimus dorsi myocutaneous flap procedure. The authors discuss the diagnosis by physical examination and x-ray confirmation, pointing out the importance of not mistaking the hernia for a seroma. Suggestions for avoiding the problem are given, relating primarily to preservation of the fascia underlying the distal latissimus aponeurosis.  相似文献   
100.
Five new quinic acid derivatives (15), together with 10 known quinic acid derivatives (615), were isolated from the MeOH extract of Pimpinella brachycarpa (Umbelliferae). Their structures were established on the basis of spectroscopic analyses including extensive 2D NMR studies (COSY, HMQC and HMBC). Isolated compounds 115 were evaluated for their inhibitory activities on nitric oxide (NO) production in an activated murine microglial cell line. Compounds 2, 3, 8 and 11 significantly inhibited NO production without high cell toxicity in lipopolysaccharide (LPS)-activated BV-2 cells, a microglia cell line (IC50 = 4.66, 12.52, 9.04 and 12.11 μM, respectively).  相似文献   
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