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When an autophagosome or an amphisome fuse with a lysosome, the resulting compartment is referred to as an autolysosome. Some people writing papers on the topic of autophagy use the terms “autolysosome” and “autophagolysosome” interchangeably. We contend that these words should be used to denote 2 different compartments, and that it is worthwhile maintaining this distinction—the autophagolysosome has a particular origin in the process of xenophagy that makes it distinct from an autolysosome.  相似文献   

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《Autophagy》2013,9(4):549-551
When an autophagosome or an amphisome fuse with a lysosome, the resulting compartment is referred to as an autolysosome. Some people writing papers on the topic of autophagy use the terms “autolysosome” and “autophagolysosome” interchangeably. We contend that these words should be used to denote 2 different compartments, and that it is worthwhile maintaining this distinction—the autophagolysosome has a particular origin in the process of xenophagy that makes it distinct from an autolysosome.  相似文献   

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Many health effects can be attributed to the Mediterranean herb oregano (Origanum vulgare L.) and several studies demonstrated the improving effect on performance, changes in blood count, antibacterial, antifungal and immunmodulating abilities. The majority of these investigations were carried out with processed essential oil, while whole plant material was only used in a few studies. Thus, the aim of the present experiment was to test the effect of increasing proportions of dried oregano in piglet feed on health and performance, with a special focus on immune modulation. A total of 80 male castrated weaned piglets (body weight [BW] 7.9 kg ±1.0 kg) were used in a feeding experiment lasting 5 weeks. They were assigned to 4 experimental groups: a control diet, and three diets with an oregano supplementation at 2 g, 4 g and 8 g per kg feed, respectively, corresponding to 23.5 mg, 46.9 mg and 93.9 mg carvacrol/kg DM. After 3 weeks, half of each group was challenged with 5 µg lipopolysaccharides (LPS) per kg BW. Blood samples were collected 2 h after LPS stimulation and analysed for T-cell phenotypes, granulocyte activity, clinical-chemistry as well as white and red blood count. The results indicate no effects of oregano on performance. In contrast, oregano altered the lymphocyte proportion and the ratio of CD4+ and CD8+ T-cells as well as the triglyceride concentration in the serum of non-stimulated and in LPS-stimulated piglets. In conclusion, whole plant supplementation of oregano to piglet feed altered immune-related parameters, but did not modulate the acute inflammatory response induced by LPS stimulation.  相似文献   

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The objective of the present study was to investigate physiological effects of a marginal copper and iron supply on pigs. Therefore an experiment was conducted with 4 × 12 growing pigs of the crossbreed Pietrain × Deutsche Landrasse. The animals were fed for a period of 119 days with a diet poor of copper (1.5 mg Cu/kg diet) and/or poor of iron (35 mg Fe/kg diet). Control animals were supplied adequately with copper (4.8 mg Cu/kg diet) and iron (85 mg Fe/kg diet). The diet was given according to weight. After reaching an average weight of 102.6 ± 3.5 kg the animals were slaughtered. Due to the activity of the coerulplasmin and katalase enzyme and the haematological parameters, the supply of copper and iron could be classified as marginal. There was no interaction between copper deficiency and iron metabolism. The protein metabolism was unchanged. Low copper intake reduced the copper concentrations in serum, liver, muscle and backfat, and low iron intake reduced the iron concentration in serum, liver and muscle. Marginal copper and iron supply had no relevant effect on either food intake and growth performance or carcass characteristics and meat quality.  相似文献   

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Beyond the energy requirement of maintenance, the assimilated energy, occurring in bioproducts, is linearly proportional to the intake of metabolizable energy in non‐underfed conditions. In contrast, resting metabolic rate is differing between individuals within a population of an animal species. As adaptability to changed environmental conditions may play a role, young bulls were exposed to thermoneutral (18°C) and low (4°C) ambient temperatures and were fed at two feeding levels (1.0 and 1.6 times energy requirement in maintenance) to produce metabolic rate differences, using the same animals, metabolic rate was altered by reducing the sympathetic outflow in each case. Expression of sulfonylurea receptors in circulating mononuclear leukocytes and cells from skeletal muscle (m. semitendinosus) was studied by flow cytom‐etry. Changes of metabolic rate at rest corresponded to the portion of cells with sulfonylurea receptors expression. The data from reducing the sympathetic outflow and those from sulfonylurea receptors expression are useful to explain metabolic rate differences among individuals of an animal population.  相似文献   

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Barley, probably the oldest cultivated cereal, is widely grown in cooler areas of the world. The annual world production of nearly two and a half billion bushels exceeds that of rye but is less than that of rice, wheat, corn and oats, respectively. Most of the annual 300 million dollar crop of the U.S. is fed to livestock, but about one- third is manufactured into malt.  相似文献   

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Liu YX 《生理科学进展》2005,36(2):97-101
刘以训教授是我国著名的生物学家,中国科学院院士。他致力于生殖生物学研究,在排卵、黄体萎缩、精子发生和胚胎植入等系列研究上,成绩卓著,享有国际声誉。读罢此文,钦敬之情油然而生。  相似文献   

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人口、食物、资源、环境与生物学钱燕文(中国科学院动物研究所北京100080)人家都说下一个世纪是生物学的世纪,人口、食物、资源、环境也是近20年来的热门话题,因为这四个方面关系到我们人类的未来。为什么下个世纪是生物学的世纪?也得从人口、食物、资源、环...  相似文献   

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Home range and habitat use of male Reeves’s pheasant (Syrmaticus reevesii) were studied during winter of 2001~2002 and 2002~2003 in the Dongzhai National Nature Reserve, Henan Province. Results from five individuals of Reeves’s pheasant with over 30 relocations, indicated that the average size of home range was 10.03 ± 1.17 hm2 by Minimum Convex Polygon method, 8.60 ± 0.35 hm2 by 90% Harmonic Mean Transformation method, and 9.50 ± 1.90 hm2 by 95% Fixed Kernel method. It was observed that the winter range is smaller than that in the breeding season. The mean core area of the home range was found to be 1.88 ± 0.37 hm2. Although the habitat composition of the core area varied greatly for individuals, a large part of the habitats used were composed of confier and broadleaf mixed forests, masson pine forests, fir forests, and shrubs. Habitat use within the study area was non-random, while habitats within home ranges were randomly used. Habitat use was dictated by tree diameter at breast height, shrub height and coverage at 2.0 m. The proximity between forests and shrubs were also found to be important in providing refuge for the birds during winter. Recommendations for conservation management include protecting the existing habitats in Dongzhai National Nature Reserve, increasing suitable habitat for Reeves’s Pheasant through artificial plantations (e.g. firs), and restoring some parts of the large shrub area into forests.  相似文献   

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Home range and habitat use of male Reeves's Pheasant(syrmaticus reevesii)were studied during winter of 2001~2002 and 2002~2003 in the Dongzhai National Nature Reserve,Henan Province.Results from five individuals of Reeves's Pheasant with over 30 relocations,indicated that the average size of home range was 10.03±1.17 hm2 by Minimum Convex Polygon method.8.60±0.35 hm2 by 90% Harmonic Mean Transformation method,and 9.50±1.90 hm2 by 95% Fixed Kernel method.It was observed that the winter range is smaller than that in the breeding season.The mean core area of the home range was found to be 1.88±0.37 hm2.Although the habitat composition of the core area varied greatly for individuals,a large part of the habitats used were composed of conifer and broadleaf mixed forests,masson pine forests,fir forests,and shrubs.Habitat use within the study area was non-random,while habitats within home ranges were randomly used.Habitat use was dictated by tree diameter at breast height,shrub height and coverage at 2.0 m.The proximity between forests and shrubs were also found to be important in providing refuge for the birds during winter.Recommendations for conservation management include protecting the existing habitats in Dongzhai National Nature Reserve,increasing suitable habitat for Reeves's Pheasant through artificial plantations(e.g.firs),and restoring some parts of the large shrub area into forests.  相似文献   

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2010年12月至2011年2月,在新疆哈密山区,采用截线抽样法和遥感技术,对野生天山马鹿(Cervus elaphus songaricus)种群现状和冬季生境选择进行了研究。在不同区域和不同类型栖息地共布设了28条样线,样线总长度达60.1 km。其中,16条样线上发现马鹿共233头,调查区域平均种群密度(2.83±1.01)头/km2,种群数量(1 684.56±379.71)头,与1993年的调查结果相比有所上升。雌雄性比为2.24:1,幼体和亚成体总数多于成体和老体总数,种群数量呈增长趋势。根据野外考察GPS数据并解译天山马鹿分布生境2006秋季的LANDSAT TM/ETM+遥感影像,将生境要素分为山地针叶林、草甸、灌木丛、农田和戈壁5种类型,其中,草甸与山地针叶林为天山马鹿冬季适宜生境。  相似文献   

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江西桃红岭国家级自然保护区梅花鹿生境适宜性评价   总被引:8,自引:4,他引:4  
华南梅花鹿(Cervus nippon)被IUCN列入濒危物种,也是我国国家Ⅰ级重点保护动物。目前种群仅分布于江西、浙江、安徽等狭窄的区域内,形成多个孤立种群,生境破碎和丧失被认为是限制梅花鹿种群增长的主要原因。于2011年3月至2013年3月采用样线法和样方法对桃红岭国家级自然保护区梅花鹿栖息地进行了野外调查,利用空间模拟方法,结合地理信息系统(GIS)技术的空间分析功能,以植被类型、坡度、坡向、海拔和人类干扰活动作为评价因子进行了生境适宜性评价。结果表明,桃红岭地区以森林为主,各类林地面积约9 488.15 hm~2,占75.90%,植被类型分为落叶阔叶林、针叶林、常绿阔叶林、针阔混交林、竹林、灌丛、草丛和芭茅丛,面积分别为1664.57、1638.63、3438.21、1247.15、87.85、1143.88、60.92 hm~2和206.94 hm~2。在不考虑人类活动影响时,梅花鹿的适宜生境和次适宜生境面积分别是2233.99 hm~2和2980.24 hm~2,分别占保护区总面积的18.61%和24.83%;而考虑人类活动影响时,梅花鹿的适宜生境和次适宜生境面积分别是1224.04 hm~2和2164.70 hm~2,分别占保护区总面积的10.20%和18.04%。由于梅花鹿的生境受到居民点、主要道路、农田耕作、森林采伐等人类活动的强烈影响,导致大量适宜和次适宜生境丧失、隔离,景观破碎度指数由0.4345增加到0.5898。以潜在可利用生境面积计算,保护区梅花鹿环境容纳量为(568±160)只,而以实际可利用生境面积计算,则只能容纳(368±105)只。适宜生境的丧失和破碎可能是限制桃红岭梅花鹿国家级自然保护区梅花鹿种群恢复的重要因素,在此基础上,通过实际调查提出了管理措施。  相似文献   

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Understanding wildlife movements and habitat selection are critical to drafting conservation and management plans. We studied a population of eastern Hermann’s tortoise (Testudo hermanni boettgeri) in a traditionally managed rural landscape in Romania, near the northern edge of the species geographic distribution. We used telemetry to radio-track 24 individuals between 2005 and 2008 and performed a Euclidian distance-based habitat selection analysis to investigate habitats preferred by tortoises at both landscapes (second-order order selection) and individual (third-order selection) home range scales. The home range size for tortoises in our study area was 3.79?±?0.62 ha and did not differ by gender or season (pre- and post-nesting seasons). Their movement ecology was characterized by short-distance movements (daily mean?=?31.18?±?1.59 m), apparently unaffected by habitat type. In contrast to other studies, movements of males and females were of similar magnitude. At the landscape (population home range) scale, grasslands and shrubs were preferred, but tortoises also showed affinity to forest edges. At the individual home range scale, tortoises selected grassland and shrub habitats, avoided forests, and used forest edges randomly. Creeks were avoided at both spatial scales. Our results suggest that tortoise home ranges contain well-defined associations of habitats despite a higher selection for grasslands. As such, avoiding land conversion to other uses and maintaining habitat heterogeneity through traditional practices (e.g., manual mowing of grasslands, livestock grazing) are critical for the persistence of tortoise populations.  相似文献   

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河南董寨白冠长尾雉繁殖期栖息地选择   总被引:2,自引:0,他引:2  
2001年至2003年春季,采用样线调查和媒鸟招引,在河南董寨国家级自然保护区对我国特有珍稀雉类白冠长尾雉(Syrmaticus reevesii)的栖息地选择进行了调查,结合RS和GIS分析了在景观水平上对栖息地的选择性,并借助逐步逻辑斯谛回归分析了影响繁殖期白冠长尾雉栖息地的关键尺度和主要因素。结果表明,在白云保护站,占区雄性白冠长尾雉在不同栖息地类型中的出现频率不同,出现最多的是混交林,其次是杉木林,随后是松林、灌丛、阔叶林;在董寨自然保护区内,在115 m尺度和250 m尺度上,针叶林的面积比例均是影响其栖息地选择的关键因子,而到农田的距离是距离因素中最重要的因素。根据回归分析和AICC及ΔAICC值,115 m尺度上栖息地变量对白冠长尾雉繁殖期的栖息地选择影响最大。综合分析表明,影响白冠长尾雉繁殖期栖息地选择的主要因子为115 m尺度上针叶林的面积比例和到农田的距离。建议在制定白冠长尾雉栖息地保护策略时,应加强现有适宜栖息地的管理,改善栖息地布局,并从景观尺度上开展针叶林对白冠长尾雉种群影响方面的研究工作。  相似文献   

17.
洪雅县人工林赤腹松鼠活动范围及栖息地利用   总被引:1,自引:0,他引:1  
2009年3~8月期间,通过观察并利用无线电遥测等方法对洪雅县林场赤腹松鼠(Callosciurus erythraeus)的活动范围和栖息地利用进行了研究。研究结果显示,赤腹松鼠的最小凸多边形(minimum convex polygon,MCP)巢域面积为(1.90±0.59)hm2,95%和60%固定核法(fixed kernel,FK)巢域面积分别为(1.06±0.19)hm2和(0.16±0.03)hm2。处在求偶高峰期的雄鼠会显著地扩大活动范围。栖息地利用的研究结果表明,赤腹松鼠对栖息地因子有明显的选择性,倾向在坡度大、灌木生长繁茂、靠近人居和水源及有藤本植物覆盖的区域活动。  相似文献   

18.
Reeves’s Pheasant, Syrmaticus reevesii, is an endemic species of China. Due to habitat loss, poaching and human disturbance, its wild population has been decreased drastically and it is listed as a globally vulnerable species by IUCN/BirdLife/WPA (IUCN 2008). Here, we report nine new polymorphic microsatellite markers isolated from the Reeves’s Pheasant. The number of alleles per locus varies between four and fourteen, with expected heterozygosity ranging from 0.349–0.776 ( = 90). These polymorphic loci provide a valuable tool for future population studies that relate to the conservation of this pheasant.  相似文献   

19.
From April to July 2003 and 2004, we surveyed the nest-site selection of the White Eared pheasant (Crossoptilon crossoptilon) in the Zhujie Monastery and in the mountain facing it in Sichuan Province, China. In this paper, we studied the nest characteristics and the clutch size of the pheasant. Habitat sampling method was used to determine the variables that might affect the nest-site selection of the White Eared pheasant. Chi-square test was used to identify which habitat type was likely to be preferred by the bird. Independent-samples t test and Mann-Whitney U test were used to find which variables were important for the birds’ nest-site selection. A total of 13 nests were found. Oak shrub was greatly preferred as nest sites (84.62%). Nests under a rock wall (7.69%) and a fallen tree (7.69%) were also found. The average clutch size of a White Eared pheasant is 7.33±0.54 (range, 5–11; n=12). Laying period was between April 27 and May 21. In the Zhujie area, 1 nest was in the forest and 11 nests were in oak shrubs. The species preferred oak shrub as its nesting habitat (χ 2=8.333, df=1, P<0.05). The bird was more likely to place its nest in sites with a high coverage, i.e. 0.5, 1, and 2 m above the ground (independent-samples t test, P<0.05), and with a large shrub diameter (Mann-Whitney U test, P<0.05). The species are more likely to prefer sites with plant cover, shrub cover (independent-samples t test, P<0.05), and shrub height (Mann-Whitney U test, P<0.05) in a relatively small range. Translated from Journal of Beijing Normal University (Natural Science), 2005, 41(2) (in Chinese)  相似文献   

20.
The social organization of Asiatic lions (Panthera leo persica) differs from African lions (P. l. leo) in that breeding lionesses defend resource based territories while male coalitions maximize coverage of female groups. Thus, lion density in the Gir forests of India is dictated by female territory size. We studied the home range and habitat preference of lions using radio telemetry on seven lionesses spaced throughout the Gir between 2002 and 2005. Radio locations obtained by homing in were plotted on a classified (LISS III FCC) habitat map of Gir to obtain habitat use and availability. Habitat preference was computed using compositional analysis and Ivlev’s index. Average (±SE) 100% Minimum Convex Polygon (MCP) range of six lionesses was 48.2 ± 10.6 km2, 95% MCP was 34.7 ± 7.8 km2 and 95% fixed kernel range size was 32.5 ± 8.2 km2. Breeding female group density and group size was about 3 per 100 km2 and 1.3 (0.5 SD, n = 45) respectively. Lions were observed to show a habitat preference (c(6df)2 = 11. 4 \chi_{(6df)}^{2} = 11. 4 , P = 0.08), the order of preference was Moist Mixed forests > Mixed forests > Savanna habitats > Teak-Acacia-Zizyphus-Anogeissus forests > Acacia-Lannea-Boswellia forests > Thorn and Scrub forests > Agriculture areas. Habitat preference during the day was for dense vegetation (c(6df)2 = 35 \chi_{(6df)}^{2} = 35 , P < 0.001). At night lions even ventured into agricultural fields. Our data suggests that dense habitats are preferred by lions in Gir to escape the heat of the day and to be in good cover when human activity was likely to be at its peak within forested areas.  相似文献   

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