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1.
我国的黑颈鹤与研究   总被引:5,自引:1,他引:4  
黑颈鹤芷云贵高原和青藏高原分布范围在北纬26°43′—39°,东径79°45′—104°18′之间;垂直分布,繁殖区在海拔2500—5000米,越冬区在海拔2200—4000米;数量在800只左右。 繁殖地四川若尔盖4—9月与越冬地贵州草海地区10—3月的主要气候指标基本相似。 在自然条件下,黑颈鹤的食物主要取食植物,一般不寻觅动物性食物。  相似文献   

2.
2005 ~2008 年于陕西省青木川自然保护区使用瞬时扫描法观察了川金丝猴的食性。结果表明,川金丝猴冬季和夏季共取食42 种植物,可鉴定植物归属23 科34 属。川金丝猴食物类型包括果实、花、树叶、树皮、树芽。夏季取食21 种植物的果实或树叶;冬季取食25 种植物。树叶是其冬季主要食物,取食频次占总取食频次的73.0% ;夏季取食果实的频次占总取食频次的72.2% ,灯台树果实是其主要食物。啃食树皮行为主要发生在落叶阔叶林、针叶林与落叶阔叶混交林;在常绿和落叶阔叶混交林中,树皮啃食强度则相对较小。与其它地区金丝猴的食性比较,该地区川金丝猴食物谱较宽。蔷薇科和壳斗科植物在川金丝猴食物组成中最多,杨柳科、桦木科、山茱萸科、槭树科和忍冬科植物也取食较多。  相似文献   

3.
人工饲养条件下四眼斑龟的食性研究   总被引:6,自引:3,他引:3  
20 0 2年6月~2 0 0 4年7月,对2 3只四眼斑龟(Sacaliaquadriocellawa) ,采用试喂法和定期投喂法进行人工饲养,对其食性进行统计分析。结果表明:2 5个月份中,四眼斑龟共取食36种食物,除饲料外,取食动物性食物14种,瓜果蔬菜及其它类食物2 2种,嗜好程度:甲鱼2号饲料>动物性食物>瓜果类>蔬菜类。平均取食12 . 1g/周·只,占体重的5 3% ;性别之间无显著差异,♀取食平均为:12. 5 g/周·只;♂为:12 . 2 g/周·只;5月取食量最大,为:2 9 7g/周·只;饲养期间平均气温、水温分别为2 6 .2℃、2 5 . 5℃,与取食量相关程度皆不显著。  相似文献   

4.
2011年1月至11月使用瞬时扫描法及焦点动物取样法对云南省大理市洱源县西湖湿地(26°00′~26°01′N,100°02′~100°03′E,平均海拔1 970 m)的紫水鸡(Porphyrio porphyrio)行为进行了观察,将行为定义为取食、寻食、休息、修饰、警戒、位移和其他共7类,扫描时将取食和寻食合并为觅食,分析非繁殖期的日节律和时间分配特点。觅食高峰出现在早晨和傍晚,低谷在秋季为下午14:30时(占所有行为类型56.56%)、冬季12:30时(55.61%)、春季11:00时(55.80%)。休息高峰秋季出现在12:30时(26.79%),冬季一日内呈上升趋势,春季呈双峰型,低谷在13:30时(14.64%)。从时间分配来看,寻食、取食、修饰等行为在不同季节间存在显著差异,寻食时间从高至低依次为冬季、春季、秋季,分别占总活动时间的19.87%、9.36%、3.03%;取食时间则相反,依次为秋季(72.54%)、春季(56.78%)及冬季(44.59%);与新西兰Pukepuke Lagoon种群相比,西湖湿地紫水鸡种群在秋季大量取食,在冬季增加寻食和休息时间,以应对高原湿地的温度和食物变化。修饰行为在繁殖期前(春季)最多(15.84%),繁殖期后(秋季)减少(11.10%)。以上结果说明,为适应气候、食物等条件的年周期变化,紫水鸡行为策略在不同时期和地点具有可塑性,这可能是该物种在滇西北地区得以繁衍及扩散的原因之一。  相似文献   

5.
2009年10月14日~12月30日,用定点直接观察法对云南曲靖地区(103°14ˊ~103°37ˊE,25°41ˊ~25°52ˊN)黄臀鹎Pycnonotus xanthorrhous的食性和取食空间生态位进行了初步观察.黄臀鹎秋冬季主要在乔木中层、树冠、灌丛等处取食,以乔木中层取食频次最高,占总取食频次的62.98%,其次是树冠和灌从,分别占15.64%和12.74%.虽然黄臀鹎秋冬季为杂食性鸟类,但其主要以植物性食物为主,占总取食频次的97.6%,而动物件食物仅占2.4%.  相似文献   

6.
洞庭湖区常绿阔叶林的特征与分析   总被引:4,自引:1,他引:3  
一、洞庭湖区常绿阔叶林的生境及自然条件洞庭湖区居荆江南岸,地理位置在北纬28°39′20″至30°14′18″,东经111°42′44″至113°39′45″之间。环湖和湖间丘陵5,044平方公里,占全区总面积的26.86%,其间保存有天然次生林106万亩。环湖和湖间丘陵多属低丘波状台地,除个别低山外,海拔多在350米以下。基岩由浅变质岩、砂页岩、石英砂岩、局部花岗岩体和厚层的第四纪红壤所组成。林地有机质含量一般在2—3%,全氮含量0.075—0.15%,速效氮、磷、钾含量为60  相似文献   

7.
山东白头鹎的一些生态观察   总被引:3,自引:3,他引:0  
据记载白头鹎Pycnontus sinensis的分布区,北至山东南部郯城(东经118°17′—118°40′、北纬34°251—34°57′)……。1984—1988年作者在山东省泰山(东经117°5′—117°24′、北纬36°5′—36°75′)、徂徕山(东经117°16′—117°20′、北纬36°02′—36°07′)的连续观察和冬季采到的标本,得知此鸟在上述两地为留鸟。常在海拔500米以下的低山一带活动,多停落在树的  相似文献   

8.
樟树叶油地理变异的研究   总被引:11,自引:3,他引:8  
对分布在福建省不同地区的樟树〔C innam omum camphora(L.)Presl〕叶油含量和主要化学成分进行分析,结果表明,J3(118°16′~119°29′)和W 1(28°18′~27°30′)交叉区域芳樟叶油含量(1.90%±0.30%)和芳樟醇含量(95.34%±1.10%)较高,可作为优良芳樟选育的重点区域;J2(117°03′~118°16′)和W 3(26°42′~25°54′)交叉区域桉樟叶油含量(1.36%±0.48%)和1,8-桉叶油素含量(10.44%±17.28%)较高,可以作为优良桉樟选育的重点区域。J2和W 2(27°30′~26°42′)交叉区域樟脑叶油含量(1.13%±0.65%)和樟脑含量(4.80%±13.97%)较高,可以作为优良脑樟选育的重点区域;J4(119°29′~120°43′)和W 6(24°18′~23°31′)交叉区域黄樟叶油含量(1.05%±0.34%)和黄樟油素含量(9.01%±16.73%)较高,可以作为优良黄樟选育的重点区域。樟树叶油含量和主成分类型及含量呈明显的地理分布。  相似文献   

9.
为了填补斑背大尾莺食性研究的空白和比较其繁殖期和非繁殖期是否有食性差异,于2011年4月繁殖期,在江西南矶湿地用望远镜观察和录像机拍摄斑背大尾莺亲鸟育雏行为,记录育雏食物的种类和数量;在11月秋季非繁殖期,斑背大尾莺专项环志过程中采集7只意外死亡的个体,进行实验室胃容物解剖分析。两种分析方法分别得出:1)春季取食动物性食物,主要有直翅目蝼蛄科成虫或幼虫、鳞翅目成虫或幼虫、蜻蜓目的成虫,蛛形纲的小型蜘蛛;2)秋季食物由动物性食物(70.24%)和植物性食物(29.76%)组成,动物性食物主要为鞘翅目、直翅目、蜻蜓目、鳞翅目、蜘蛛目等节肢动物,植物性食物为一些植物种子和少量的叶片组织。本研究表明,繁殖期和非繁殖期斑背大尾莺食性有差异,这种差异性是随季节变化生境中的食物组成不同,及育雏期雏鸟需高蛋白营养食物而导致的。  相似文献   

10.
我们于2005年8月19日晚10时左右,在位于重庆市巴南区花溪镇的重庆清华中学华溪苑小区室内采集到一号翼手类标本,雄性,经鉴定系伏翼(Pipistrellus pipistrellus[Schreber,1774]),为重庆市新记录。标本现保存于重庆清华中学动物标本室。报道如下。捕捉地重庆清华中学(海拔185~230 m)所在重庆市巴南区,地理位置为106°24′45″~106°59′58″E,29°7′45″~29°46′23″N,地处川东平行岭谷向南侵没与盆地南缘山地的交接地带,年平均日照数为1159 h,年平均降水量1090mm,年平均相对湿度81%,属亚热带湿润性季风气候。1形态特征体重4·5 g,体长44…  相似文献   

11.
正Dear Editor,In December 2019, a novel human coronavirus caused an epidemic of severe pneumonia(Coronavirus Disease 2019,COVID-19) in Wuhan, Hubei, China(Wu et al. 2020; Zhu et al. 2020). So far, this virus has spread to all areas of China and even to other countries. The epidemic has caused 67,102 confirmed infections with 1526 fatal cases  相似文献   

12.
Curcumin is the yellow pigment of turmeric that interacts irreversibly forming an adduct with thioredoxin reductase (TrxR), an enzyme responsible for redox control of cell and defence against oxidative stress. Docking at both the active sites of TrxR was performed to compare the potency of three naturally occurring curcuminoids, namely curcumin, demethoxy curcumin and bis-demethoxy curcumin. Results show that active sites of TrxR occur at the junction of E and F chains. Volume and area of both cavities is predicted. It has been concluded by distance mapping of the most active conformations that Se atom of catalytic residue SeCYS498, is at a distance of 3.56 from C13 of demethoxy curcumin at the E chain active site, whereas C13 carbon atom forms adduct with Se atom of SeCys 498. We report that at least one methoxy group in curcuminoids is necessary for interation with catalytic residues of thioredoxin. Pharmacophore of both active sites of the TrxR receptor for curcumin and demethoxy curcumin molecules has been drawn and proposed for design and synthesis of most probable potent antiproliferative synthetic drugs.  相似文献   

13.
14.
The young pistils in the melanthioid tribes, Hewardieae, Petrosavieae and Tricyrteae, are uniformly tricarpellate and syncarpous. They lack raphide idioblasts. All are multiovulate, with bitegmic ovules. The Petrosavieae are marked by the presence of septal glands and incomplete syncarpy. Tepals and stamens adhere to the ovary in the Hewardieae and the Petrosavieae but not in the Tricyrteae. Two vascular bundles occur in the stamens of the Hewartlieae and Tricyrtis latifolia. Ventral bundles in the upper part of the ovary of the Hewardieae are continuous with compound septal bundles and placental bundles in the lower part. Putative ventral bundles occur in the alternate position in the Tricyrteae and putative placental bundles in the opposite. position in the Petrosavieae. The dichtomously branched stigma in each carpel of the Tricyrteae is supplied by a bifurcated dorsal bundle.  相似文献   

15.
16.
Highlights
1. The N-terminal tail of histone H3 is specifically cleaved during EV71 infection.
2. Viral protease 3C is identified as a protease responsible for proteolytically processing the N-terminal H3 tail.
3. Our finding reveals a new epigenetic regulatory mechanism for Enterovirus 71 in virus-host interactions.  相似文献   

17.
Rasmussen’s encephalitis (RE) is a rare pediatric neurological disorder, and the exact etiology is not clear. Viral infection may be involved in the pathogenesis of RE, but conflicting results have reported. In this study, we evaluated the expression of both Epstein-Barr virus (EBV) and human herpes virus (HHV) 6 antigens in brain sections from 30 patients with RE and 16 control individuals by immunohistochemistry. In the RE group, EBV and HHV6 antigens were detected in 56.7% (17/30) and 50% (15/30) of individuals, respectively. In contrast, no detectable EBV and HHV6 antigen expression was found in brain tissues of the control group. The co-expression of EBV and HHV6 was detected in 20.0% (6/30) of individuals. In particular, a 4-year-old boy had a typical clinical course, including a medical history of viral encephalitis, intractable epilepsy, and hemispheric atrophy. The co-expression of EBV and HHV6 was detected in neurons and astrocytes in the brain tissue, accompanied by a high frequency of CD8+ T cells. Our results suggest that EBV and HHV6 infection and the activation of CD8+ T cells are involved in the pathogenesis of RE.  相似文献   

18.
19.
Shen  Jia-Yuan  Li  Man  Xie  Lyu  Mao  Jia-Rong  Zhou  Hong-Ning  Wang  Pei-Gang  Jiang  Jin-Yong  An  Jing 《中国病毒学》2021,36(1):145-148
正Dear Editor,Chikungunya virus (CHIKV), an arbovirus in the family of Togaviridae, genus Alphavirus, is transmitted by the A.aegyptii or A. albopictus mosquito, and causes disease in humans characterized by fever, rash, and arthralgia (Silva and Dermody 2017; Suhrbier 2019). It was first reported in 1953 in Tanzania, and caused only a few outbreaks and sporadic cases in Africa and Asia in last century. However, in the epidemic in 2004, CHIKV acquired mutations that conferred enhanced transmission by the A. albopictus mosquito(Schuffenecker et al. 2006). Since then, it has successively caused outbreaks in Africa, the Indian Ocean, South East Asia, the South America, and Europe (Zeller et al. 2016).  相似文献   

20.
In conclusion, the novel visual RT-LAMP assay is a simple, rapid, and sensitive approach for detection of SARS-CoV-2, and it is ready for application in primary care and community hospitals or health care centers, and even patients' own houses in response to the current SARS-CoV-2 epidemic because the assay does not require sophisticated equipment and skilled personnel. Furthermore, it is also ready to be used in fields for screening samples from wild animals and environments to facilitate the identification of potential intermediate hosts that mediate the cross-species transmission of SARS-CoV-2 from bats to humans.  相似文献   

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