关键词： defaunation   ecosystem services   frugivores   habitat loss   herbivores  

摘要： The Gran Chaco in central South America is a major savanna woodland ecosystem. Accelerated changes in land use within it have resulted in a complex matrix of areas with varying capabilities for sustaining wildlife. Furthermore, hunting and habitat loss increasingly threaten the functional diversity of mammals found there. We assess the potential consequences of the loss of large and medium-sized native mammalian herbivores and frugivores on Chacoan ecosystem functioning, focusing on their role and conservation status in the Argentine Chaco. Our review shows that almost 50% of the largest frugivorous mammals present in the Argentine Chaco are threatened and exhibit declining population trends. Their decline may cause changes in vegetation composition, since almost 53% of the Chacoan woody plant species display endozoochory as their seed dispersal mechanism. Moreover, 80% of the largest herbivores are threatened, which may also lead to a compositional change in savanna vegetation. There is a significant void of information regarding the population status of native mammals in the Argentine Chaco and the functional roles they play in the ecosystem, and there are few studies examining the consequences of their potential loss. We express our concern with the major changes taking place in this subtropical region due to significant and rapid habitat transformations and emphasize the important role of ecological functionality in restoration and conservation planning in the Gran Chaco.

关键词： 肾阴虚型   老年痴呆证   中药治疗   病证结合   六味地黄丸   药效评价  

摘要： 目的:肾虚证是老年痴呆较常见的证型，研究肾虚型老年痴呆病及抗痴呆的中药治疗，意义重大。并且树鼩是研究脑疾病方面较理想的实验动物。本研究旨在以树鼩为对象，构建肾阴虚型老年痴呆病模型，为防治老年性痴呆及相关药物的研发提供病证结合的动物模型。　　方法:　　(1)肾阴虚型树鼩动物模型的建立。摸索出氢化可的松造肾阴虚证的给药途径、最佳剂量、给药时间。方法一:分别腹腔注射生理盐水、低剂量（1mg/100g体重）氢化可的松、中剂量（1.5mg/100g体重）氢化可的松、高剂量（2mg/100g体重）氢化可的松，连续5天。方法二:分别腹腔注射生理盐水、低剂量（1mg/100g体重）氢化可的松、高剂量（1.5mg/100g体重）氢化可的松，连续7天。在造模期间每天测量树鼩体重并观察毛发、粪便等一般状态。在给药结束后，测量每组动物血清中游离三碘甲状腺原氨酸(FT3)、游离甲状腺素(FT4)、雌二醇(E2)、睾酮、皮质醇(CORT)的含量，脏器指数。　　(2)老年痴呆树鼩动物模型的建立。方法一:分别腹腔注射生理盐水、低剂量（0.5ml/100g体重）0.96％D-半乳糖、高剂量（0.5ml/100g体重）1.92％D-半乳糖，连续6周。6周后造模组进行双侧脑室注射鹅膏蕈氨酸(IBO)5μg，空白组在相应位置注射生理盐水。方法二:分别双侧脑室注射生理盐水、低剂量(Aβ25-355μg+IBO5μg)、高剂量（Aβ25-3510μg+IBO5μg）。在造模期间每天测量树鼩体重并观察毛发、粪便等一般状态。在给药结束后测量脏器指数，观察脑组织病理形态变化，比较脑组织中乙酰胆碱转移酶(CHAT)、突触素(SYP)、APP、Aβ1-42、磷酸化tau(P-tau)、去甲肾上腺素(NE)的含量。　　(3)肾阴虚型老年痴呆模型的建立和六味地黄丸的干预作用。将动物随机分成四组。空白组:第一天双侧脑室注射生理盐水，之后腹腔注射生理盐水连续3天，灌胃蒸馏水连续10天;AD组:第一天双侧脑室同时注射Aβ25.3510μg和IBO5μg，之后腹腔注射生理盐水连续3天，灌胃蒸馏水连续10天;肾阴虚型AD组:第一天双侧脑室同时注射Aβ25-3510μg和IBO5μg，之后腹腔注射氢化可的松（1mg/100g体重）连续3天，灌胃蒸馏水连续10天;六味地黄丸治疗组:第一天双侧脑室同时注射Aβ25-3510μg和IBO5μg，之后腹腔注射氢化可的松（1mg/100g体重）连续3天，灌胃六味地黄丸（1mg/100g体重，2mg/ml）连续10天。在给药造模期间每天测量树鼩体重记录一般状态。在给药结束后，测量相应的生化指标、脏器指数、观察脑组织的病理形态变化、比较脑组织中CHAT、SYP、APP、Aβ1-42、P-tau、NE的含量。　　结果:　　(1)在肾阴虚模型部分，方法一:与空白组比较，高剂量组出现肌肉萎缩，四肢瘦瘪少光泽，皮肤疏松，但活动力差，状态不好;中剂量组出现大便干结，肌肉萎缩，四肢瘦瘪少光泽，皮毛无光泽，活力较强;低剂量组皮毛无光泽，生命指征良好，皮质醇水平显著下降(p＜0.05)。方法二:高剂量组出现大便干结、肌肉萎缩、四肢瘦瘪少光泽、皮毛无光泽且生命体征较弱，FT3和睾酮水平均显著下降(p＜0.05），甲状腺指数显著降低(p＜0.05）;低剂量组出现易惊躁动、大便干结、肌肉萎缩、皮毛无光泽，FT3和CORT水平显著降低(p＜0.05)，E2水平显著升高(p＜0.05)。结果表明，方法二中的低剂量(1mg/100g)，腹腔注射连续7天后，树鼩的状态及各项指标较符合肾阴虚证的表现。　　(2)在老年痴呆模型部分，方法一:与空白组比较，高剂量组一般状态变化为毛发少光泽且掉毛严重，食盒中有粪便;脑组织中神经元细胞发生核固缩成不规则形，胞浆、胞核界限不明显，细胞周围间隙大，排列紊乱，神经纤维排列杂乱，锥体细胞大量缺失;CHAT免疫阳性神经元数目和SYP反应产物的量大量减少，平均截面积非常显著下降(p＜0.01);APP、Aβ1-42、 P-tau蛋白的灰度值非常显著性增多(p＜0.01），脑组织的NE含量显著减少(p＜0.05）。低剂量组一般状态变化为躁动易惊，上下逃窜，毛发少光泽，掉毛，食盒中有粪便;脑组织中神经元细胞发生核固缩成不规则形，细胞稀疏，锥体细胞变小;CHAT免疫阳性神经元数量和SYP反应产物的量减少，平均截面积非常显著降低(p＜0.01);APP、Aβ1-42、P-tau蛋白的灰度值非常显著性增多(p＜0.01）。方法二:高剂量组一般状态变化为毛发少光泽且掉毛严重，将粪便拉在食盒当中，体重显著性降低(p＜0.05）;脑组织中神经元发生核固缩成不规则形，胞浆、胞核界限不明显，细胞周围间隙大，排列紊乱，神经纤维排列杂乱，锥体细胞大量缺失;CHAT免疫阳性神经元数量和S

关键词： Agamidae   Caloes emma   Lizard   Northeast India   Range extension   Tripura  

摘要： Two new records of Calotes emma Gray, 1845, are reported from Srirampur and Homnpui in the state of Tripura, northeast India. These records are the first from Tripura. Present locality records extended the known distribution of C. emma in Southeast Asia. © 2015 Check List and Authors.

关键词： 脉络膜新生血管   树鼩   动物模型   VEGF   PIGF-1  

摘要： 一、研究目的：探讨利用激光诱导建立树鼩脉络膜新生血管动物模型的可行性、形态学和组织学变化。二、实验方法：,1.激光损伤动物模型制作选取成年健康树鼩25只(48只眼),分为6组,每组4只(8眼),第6组为空白对照组。空白对照组不做任何处理.模型建立的方法：树鼩腹腔内注射戊巴比妥钠麻醉后,复方托吡卡胺散瞳三次,盐酸奥布卡因眼表面麻醉,对试验1-5组进行氪红激光视网膜光凝,每眼距离视盘约1PD位置做8个光凝点,出现爆破音和视网膜上有水泡改变,证明Bruch膜成功受到破坏。2、建模成功的判定激光光凝术后有气泡形成,标志Bruch’s膜破裂,成为CNV形成的基础,以FFA出现荧光渗漏作为建模成功的评判标准。3、模型的组织学评价(1)FFA：分别于光凝后3、7、14、21、28d,行FFA检查。CNV判定取造影晚期像(FFA>5min)观察CNV形成渗漏情况。计算机图像分析系统计算每个时间点CNV的荧光素渗漏积分面积。(2)免疫组化检测包括：VEGF-A、PIGF、Ⅷ因子。4、统计分析经过统计分析,判断动物模型建立的成功率、临床表现和组织病理表现与人类疾病过程的相似程度,对激光诱导树鼩CNV模型建立进行总体评价。三、研究结果：1.在同一时间点早、中、晚期FFA荧光渗漏面积可看出中、晚期渗漏面积大于早期,p<0.05, FFA渗漏面积早、中、晚期渗漏面差异性,有统计学意义。在不同时间点FFA同一时期表现出7～14天为渗漏面积高峰时期,随着3天、7天、14天、21天、28天时间的增加,FFA渗漏面积增加,p<0.005, FFA渗漏面积在不同的时间点的差异,有统计学意义。2.树鼩生物学分类接近于灵长类,视网膜结构与人类非常相似,HE染色可见,空白对照组的正常树鼩视网膜、脉络膜各层组织结构清晰,完整,分为十层,从内到外依次为内界膜、神经纤维层、节细胞层,内从状层、内核层、外丛状层、外核层、外界膜、视锥视杆细胞层、色素上皮层。实验1-5组激光损伤后可见视网膜各层广泛的血管扩张和管腔内淤血。3.实验组与空白组激光光凝术后进行PIGF、VEGF-AⅧ因子染色比较：运用SPSS17.0软件,实验结果以均数±标准差表示,对实验组术后激光着色强度、着色面积、总分情况进行方差齐性检验,结果P<0.05。经t检验, 实验组与空白组经PIGF、VEGF-A染色,实验组与空白组相比较随着造模时间延长,表达显著增高,差异有统计学意义。(P<0.05)。Ⅷ因子染色,经t检验,实验组从第14天开始随着造模时间延长表达才出现增高,从第14天起实验组对照组差异有统计学意义。(P<0.05)。可认为在激光损伤树鼩视网膜后VEGF、 PIGF-1、Ⅷ因子表达显著增高。四、结论：1.氪红激光视网膜光凝术可诱导树鼩脉络膜新生血管的形成。2.病理切片HE染色结果仅显示视网膜节细胞层广泛血管扩张和管内淤血,未见机械损伤,未能显示脉络膜新生血管的生长,可能与病理切片取材部位不准确有关。3.在激光损伤树鼩视网膜后,视网膜新生血管生长的相关因子均出现阳性表达,且表达的强度随观察时间延长而增强,出现阳性表达的时间VEGF和PIGF-1为激光后第7天,Ⅷ因子为第14天。

关键词： 卡耐基  

摘要： 钢铁大王卡耐基去往纽约市中心一幢高层建筑物,他要乘电梯到高层一间写字间。电梯里,他遇上了一位开电梯的人,这人的左手被齐腕砍断。于是,他问这位没有手的人,会不会因为没有手感到难过。得到的答案,让卡耐基大感意外,开电梯的人说:"噢,不会,我根本就不会想到它。只有在要穿针的时候,才会想到这件事。"举重若轻,诙谐幽默。谁会真的相信,没有手的人,只会在穿针的时候才想到手。只是生活中趋利避害的法则告诉人们,对已经发生的或必

关键词： Browser   Bush encroachment   Nutrients   Woody structure   Livestock   Wildlife  

摘要： The structure and composition of woody and grassy vegetation in savannas is strongly influenced by herbivores. In recent decades, the proportion of browsers has declined across African savannas in favour of more grazers, triggered by large-scale human-induced cattle grazing. This has led to overgrazing and an imbalance of woody and grassy vegetation. Our study investigated mono-specific and multi-species herbivore assemblages of varying density and assessed similarities in vegetation patterns under wildlife and livestock herbivory in and around Kruger National Park, South Africa. Under mono-specific herbivory, overall tree cover was more than twice as high compared to multi-species herbivory while the branch. ing height of small and tall trees was lowest. Small tree and bush densities were strongly elevated at mono-specific compared to multi-species herbivore sites. Tall trees were dominated by Acacia nigrescens under multi-species herbivory at low wildlife density but not at high density sites. Grass leaf nitrogen contents were almost twice as high at multi compared to mono herbivory sites, particularly beneath tree canopies. Livestock and wildlife herbivore sites showed similar patterns in their woody plant structure and grass nutrients. We conclude that a characteristic herbaceous and woody vegetation structure as well as species composition can be matched with mammalian herbivore communities, which has implications for landscape heterogeneity and grazing management in savanna systems. (C) 2014 Geobotanisches Institut ETH, Stiftung Ruebel. Published by Elsevier GmbH. All rights reserved.

关键词： 咽鼓管   分泌性中耳炎   动物模型   电凝堵塞  

摘要： 目的:研究树鼩咽鼓管解剖结构,行树鼩头颅Micro-CT扫描;建立分泌性中耳炎的树鼩动物模型。方法:选取26只健康成年树鼩作为实验对象,分成2组(解剖组和模型组)解剖组(树鼩咽鼓管解剖及micro-CT扫描):选取10只健康成年树鼩,进行显微解剖,其中6只行micro-CT扫描,通过mimics15.0软件对micro-CT扫描数据进行分析。模型组(树鼩分泌性中耳炎模型的建立):选取16只健康成年树鼩,采用电凝法堵塞咽鼓管咽口建立分泌性中耳炎模型,所有动物右耳为实验耳,左耳为对照耳。造模后第3天进行耳显微镜检查、第3天行声导抗检查、第10天行MicroCT检查,于造模后第7天、第28天行中耳病理检查。结果:1.解剖组:解剖显微镜下发现:1.1.咽鼓管大体形态树鼩咽鼓管是一管状结构,咽鼓管咽口位于鼻咽外侧壁,其上方为颅底,下方为软腭,前方为后鼻孔,后方为鼻咽及口咽交界处,鼓室口位于中鼓室前上部,在鼓室前壁与内壁交界处向前下方鼻咽部方向走行。1.2.咽鼓管管壁构成树鼩咽鼓管分为三部分:粘膜部、软骨部和骨部。在咽鼓管的横截面上,咽鼓管软骨呈“C”形。软骨部和骨部交界处为咽鼓管最狭窄处。1.3.腭帆张肌(TVP)腭帆张肌由二组肌肉纤维组成,内组较大,起源于听泡、蝶骨大翼、翼状突,外组较小,起源于软骨外侧板,接近软骨部和骨部交界处。1.4.腭帆提肌(LVP);腭帆提肌起源于软骨内侧板近软骨部和骨部交界处.肌肉束向前内方向走形,最后融入到软腭后方.*** CT扫描结果显示:MicroCT扫描可清晰显示骨性结构,颅骨、硬腭、鼻甲、听泡、听骨、耳蜗等结构。但对软组织显示较差。Micro-CT扫描发现:树鼩听泡分为,内、中、外三个气房,外侧听泡较大,中间听泡较小。咽鼓管咽口黏膜部位于内听泡外侧,咽鼓管鼓口开口位于外听泡内侧,软骨部全长贯穿于内听泡。咽鼓管骨部位于外侧听泡。咽鼓管狭窄部位于内听泡与外听泡间隔处。2.模型组:2.1.耳显微镜观察鼓膜情况:实验耳(右耳)鼓膜颜色呈橘黄色,鼓室内可见积液存在。在对照耳(左耳)鼓膜正常,鼓室内无积液。2.2.声导抗鼓室图:实验耳声导抗鼓室图均显示为“B型”。在对照耳声导抗鼓室图均显示为“A 型”。***-CT 扫描结果:通过Micro-CT图像对树鼩手术耳侧进行影像学观察。所有树鼩实验耳的听泡内可见积液存在,符合分泌性中耳炎的征象。在所有的对照耳中未发现明显积液存在。2.4.病理检查;第7天:通过显微镜观察到中耳内部有白细胞浸润现象,粘膜层扩张,有大量的破骨细胞和成骨细胞出现。骨细胞和成骨细胞的数量增加表明出现骨膜增生。另外,纤维细胞和胶原纤维细胞的数量有所增加,上皮细胞层出现的血管扩张、水肿和淋巴细胞导致中耳粘膜增厚。第28天:用光学显微镜观察到,中耳粘膜厚度与第7天时的厚度相比增厚,同时也出现了水肿,这是慢性传染的症状。所有动物的炎症细胞的数量和在第7天时的数量相比有所增多。结论:1.树鼩咽鼓管分为粘膜部、软骨部和骨部;管周肌肉主要是腭帆张肌和腭帆提肌;树鼩咽鼓管的观察结果可为进一步研究咽鼓管功能以及病理生理变化提供解剖学依据。2.通过鼓膜观察、鼓室导抗图、颞骨Micro-CT及中耳病理检查,证实电凝法堵塞咽鼓管咽口,能有效诱发树鼩分泌性中耳炎,此动物模型可作为进一步研究分泌性中耳炎发病机制、诊断及治疗的模型。

关键词： manipulative experiment   mark-recapture   predator-prey interactions   predator-proof fences   reintroduction   small-mammal extinction   survival  

摘要： Small mammal species are declining across northern Australia. Predation by feral cats Felis sylvestris catus is one hypothesised cause. Most evidence of cat impacts on native prey comes from islands, where cat densities are often high, but cats typically occur at low densities on mainland Australia. We conducted a field experiment to measure the effect of predation by low-density cat populations on the demography of a native small mammal. We established two 125-ha enclosures in tropical savanna in the Northern Territory. Each enclosure was divided in half, with cats allowed access to one half but not the other. We introduced about 20 individuals of a native rodent, Rattus villosissimus, into each of the four compartments (two enclosuresxtwo predator-access treatments). We monitored rat demography by mark-recapture analysis and radiotracking, and predator incursions by camera surveillance and track and scat searches. Rat populations persisted over the duration of the study (18months) in the predator-proof treatment, where we detected no predator incursions, but declined to extinction in both predator-accessible compartments. In one case, cat incursions were frequently detected and the rat population was rapidly extirpated (<3months);in the other, cat incursions were infrequent, and the population declined more gradually (c. 16months) due to low recruitment. We detected no incursions by dingoes Canis dingo, the other mammalian predator in the area. Synthesis and applications. This is the first study to provide direct evidence that cats are capable of extirpating small mammals in a continental setting, in spite of their low population densities. This finding supports the hypothesis that predation by feral cats is contributing to declines of small mammals in northern Australia. The conservation management of native small mammals in northern Australia may require intensive control of cat populations, including large cat-free enclosures.

关键词： Abundance   Amazon savanna   Brazil   Medium and large mammals   Richness  

摘要： In this study, we investigated the effects of the partial conversion of native Amazon savanna into a eucalyptus plantation on the richness, composition, and abundance of medium and large mammals. Considering these plantations as an integral component of a patchwork savanna landscape, we verified how the negative effects of these plantations can be buffered by the conservation of remnants of native habitat within their area. We analyzed the contribution of each type of Amazonian savanna to the maintenance of the mammalian fauna and the potential of eucalyptus plantations to substitute these native habitats. A total of 23 mammal species were recorded in line-transect surveys conducted within the conserved savanna. By contrast, only eight species were recorded in the eucalyptus plantation and none of them were exclusive to this vegetation. However, the landscape patchwork formed by plantations and savanna was more diverse and contained 19 species of mammals, highlighting the potential importance of remnant savanna vegetation. The maintenance of remnants of savanna habitat may thus be essential for ensuring the conservation of mammals in the anthropogenic landscape of this region. It will also be important to include as many different subtypes of native savanna vegetation as possible and to consider the connectivity between habitats.

关键词： Dendrometer   Dichrostachys   Elephant   Exclusion experiment   Long-term monitoring   Survival  

摘要： Seasonality is a characteristic feature of savannas. Assuming plants are dormant in the dry season, long-term browsing by large herbivores (or their exclusion) in savannas should affect stem growth in the wet season alone. In addition, plant survival should improve with exclusion. A total of 236 dendrometers on six woody species in three large (> 25 ha) plots (all large herbivores excluded, elephants excluded, control-no large herbivores excluded) were observed from 2006 to 2013 in Kruger National Park, South Africa. Average monthly increment (AMI) per dendrometer was calculated and the interaction between exclusion and season (dry or wet) was tested species-wise. The AMIs of Acacia exuvialis, Combretum apiculatum, Dichrostachys cinerea and Grewia flavescens were generally reduced by herbivore exclusion, while the unpalatable Euclea divinorum was unaffected. Survival rates of C. apiculatum and E. divinorum were not significantly associated with exclusion, while other species' survival rates benefitted from exclusion. The dry-season AMIs of all species were significantly lower than wet-season AMIs, but dry-season AMIs were positive for two species common on footslopes (A. grandicornuta and E. divinorum), while being almost zero for species common on midslopes and crests, possibly because of hydrological variation on the catena. The results suggested that stem circumference growth of prominent woody species in semi-arid savannas is prone to reduction by exclusion of large herbivores, except for generally unpalatable species. Large herbivores may affect woody stem growth in semi-arid savannas by altering competition among plants.