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1.
Macromorphology and encephalization (EI) of brains were compared in 58 Vespertilionid species, brain composition in 36 species: 46 or 27 species of Vespertilioninae, 8 or 5 species of Miniopterinae, 2 species of Kerivoulinae, and 2 species of Nyctophilinae. Subfamily differences were found in the extent of the cover of the mesencephalon. It is nearly fully covered in Kerivoula papulosa (Kerivoulinae), at least half covered (by the cerebellum) in Miniopterinae, and free (completely or nearly so) in Nyctophilinae and Vespertilioninae. In relative brain size, the Kerivoulinae are highest (average EI = 130), followed by the Miniopterinae (111), Nyctophilinae (102) and Vespertilioninae (95). The higher encephalization of Kerivoulinae and Miniopterinae is accompanied by a marked increase of relative size in cerebellum and striatum, and in Kerivoulinae, in hippocampus and neocortex as well.  相似文献   

2.
The large size of the hippocampus in the papillose bat (Kerivoula papulosa) (see Part I) is paralleled by a structural differentiation of area CA 1 which is unique among Vespertilionids, and possibly Chiroptera in general. CA 1 of the papillose bat has a very thick band of cells which fills about 2/3 of the whole thickness of CA 1, in contrast to a maximum of 1/3 in other Vespertilionids. As in primates, the cells are dispersed over the whole stratum oriens and reach the alveus. Unlike in primates, however, the cells seem to migrate also in the direction of the periphery, i. e. into the sub-stratum radiatum of the molecular layer. Only a relatively small outer cell-poor band remains (1/4 of the whole thickness versus more than 1/2 in primates; Table 2). In K. papulosa the cell band of CA 1 is clearly thicker than that of the adjacent neocortex, separated by the lateral ventricle (Fig. 4). So far we have no strong arguments to correlate this very specific structural character with any particular behavior in K. papulosa.  相似文献   

3.
广西扁颅蝠与褐扁颅蝠的食物选择   总被引:3,自引:1,他引:2  
2002年3~10日在广西南宁地区的宁明县和龙州县,用超声波监测和网捕法确定扁颅蝠与褐扁颅蝠的捕食区,在捕食区内用粘捕法调查潜在的食物量;用粪便分析法确定食物组成。在宁明县和龙州县扁颅蝠和褐扁颅蝠的潜在食物量都是以双翅目昆虫为主(45.93%以上),其次为鞘翅目(12.59%以上)和膜翅目(7.47%以上);但双翅目、膜翅目在两地差异显著。宁明县扁颅蝠的食物组成以双翅目(40.33%)和膜翅目(38.46%)为主,鞘翅目(16.07%)次之;龙州县扁颅蝠和褐扁颅蝠食物组成中以膜翅目(63.37%,62.34%)为主,其次为双翅目(21.57%,29.62%)、鞘翅目(11.59%,5.96%);对比两地扁颅蝠的食物组成发现,膜翅目和双翅目差异极显著。对比食物组成与潜在食物量发现,两种蝙蝠对膜翅目为正选择,对其他目负选择或无选择,均为选择性捕食者。  相似文献   

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我们于2002 ~ 2007 年在广西龙州县和宁明县采用标记重捕法对扁颅蝠的扩散行为进行研究, 共标记669 只(成体316 只,亚成体353 只;雌雄分别为293 只和376 只),重捕到139 只(重捕率20. 8% )。结果表明,大部分扁颅蝠雌雄后代在性成熟前发生扩散,其亚成体扩散率无性别差异(雄
性82.2% ,雌性66.7% ;P > 0.05)。对成年雌雄两性扩散率(雄性76.5% ,雌性58.5% )的分析亦未见性别差异(P > 0.05),但亚成体和成体合并结果显示雄蝠扩散率(80.7% )高于雌蝠(62.3% ,P < 0.01)。此外,我们还测量了扩散的距离,雄性后代的扩散距离(787. 5 ± 26.980 m,n = 37)比雌
性(517.4 ± 25.308 m,n = 24)远(P < 0. 01);在出现扩散的61 只后代中,仅有一只(0. 7% )雄性亚成体扩散到其它的竹林,其余个体均在出生竹林内的不同竹筒之间进行扩散。  相似文献   

5.
该文通过野外调查和室内行为实验,研究了扁颅蝠(Tylonycteris pachypus)和褐扁颅蝠(T.robustula)与其体表寄生革螨(雷氏巨刺螨(Macronyssus radovskyi)及拟雷氏巨刺螨(M.pararadovskyi))之间的关系.在野外自然条件下,雌性扁颅蝠的体表寄生革螨负荷量与宿主健康指数呈正相关(Spearman:rs=0.55,P<0.01,n=24),而在雄性扁颅蝠以及雌、雄褐扁颅蝠中则无相关性(P>0.05).室内原宿主感染实验发现,扁颅蝠和褐扁颅蝠体表寄生革螨均明显倾向于选择各自的雄性宿主,扁颅蝠雌、雄性感染率分别为(42±12)%和(58±12)%(t=-3.6,df=31,P<0.01);褐扁颅蝠雌、雄性感染率分别为(37±11)%和(63±11)%(t=-6.1,df=26,P<0.001).用扁颅蝠体表寄生革螨(拟雷氏巨刺螨)对扁颅蝠与褐扁颅蝠交叉感染后发现,寄生革螨明显选择其原宿主扁颅蝠,扁颅蝠与褐扁颅蝠感染率分别为(71±13)%和(29±13)%(t=9.1,df=29,P<0.001).以上结果表明,扁颅蝠和褐扁颅蝠的体表寄生革螨负荷量与宿主身体状态无明显相关性,而对宿主性别表现不同偏好;扁颅蝠的体表寄生革螨对宿主表现明显的专一性.  相似文献   

6.
13 novel microsatellite loci was isolated using the enriched library method from genomic DNA of the flat-headed bat (Tylonycteris pachypus). These loci showed high levels of genetic polymorphism testing on 54 individuals sampled from Guangxi province, China. The number of observed alleles per locus ranged from 2 to 15. The expected and observed heterozygosity values ranged from 0.170 to 0.900 and from 0.185 to 0.944, respectively. One loci departed significantly from Hardy-Weinberg equilibrium (HWE) after Bonferroni correction and no Linkage disequilibrium was found between any pairs of loci. In addition, these loci were tested in the sister species, Tylonycteris robustula, seven loci amplified successfully and were also polymorphic.  相似文献   

7.
The expression of class II major histocompatibility complex (MHC) antigens on alveolar epithelial cells and macrophages was investigated immunocytochemically in paraquat-induced alveolitis in the rat lung. Until 2 days after paraquat injection, class II MHC antigens were expressed on the type II alveolar epithelium without any inflammatory cellular infiltration. From the 4th to the 7th day after paraquat injection, class II MHC antigen-positive macrophages increased in the alveolar spaces, whereas the expression on the type II alveolar epithelium became obscure. Over 10 days after the injection, interstitial fibrosis progressed and the intra-alveolar inflammatory infiltrates decreased. Epithelial cells lining the thickened fibrous septa no longer expressed class II MHC antigens. These results suggest that chemical stimuli can induce class II MHC antigen expression on the type II alveolar epithelium in the early stage of cellular injury, followed by inflammatory infiltration and interstitial fibrosis.  相似文献   

8.
The Japanese quail drinks water vigorously after water deprivation, haemorrhage and administration of hypertonic saline solution. Most avian species responded to angiotensin II (AII) by drinking, but carnivorous birds and those originating in arid regions were insensitive. The receptive sites for AII were the subfornical organ (SFO) and the preoptic area (POA) in the Japanese quail. Catecholaminergic fibers proceed from the POA to the SFO. Dipsogenic information generated by AII at the POA is transferred to the SFO through the catecholaminergic nerve fibres. Plasma AII increased following dehydration and haemorrhage and returned to a normal level immediately after rehydration. Following dehydration, arginine vasotocin, aldosterone and corticosterone increased in plasma as well as AII. A single intraperitoneal injection of AII induced increases of arginine vasotocin, aldosterone and corticosterone in plasma. It seems that AII functions as a trigger for release of these other hormones during dehydration.  相似文献   

9.
扁颅蝠与褐扁颅蝠的集群结构   总被引:4,自引:0,他引:4  
2001—2002年在广西宁明县和龙州县利用直接观察、捕捉测量(共捕到197群蝙蝠,全捕180群)和标记重捕法(标记了31群的101只扁颅蝠,重捕到36只)比较研究了扁颅蝠(tylonycteris pachypusa)与褐扁颅蝠(T.robustula)的集群结构。结果发现:扁颅蝠与褐扁颅蝠主要栖宿在刺竹(Bambusa stenostachya)的竹筒内,通过竹筒上的裂缝进出。扁颅蝠栖宿的竹筒长平均为27.7cm,外围直径平均为23.6cm;褐扁颅蝠的分别为28.3cm和23.8cm。扁颅蝠栖宿群大小为1—24只,褐扁颅蝠栖宿群大小为1—13只;2种蝙蝠的栖宿群中皆为独居所占比例最大(扁颅蝠为22.30%,褐扁颅蝠为40.63%),2只所占比例次之(分别为14.87%和18.75%),其它大小类型呈不规则变化。扁颅蝠栖宿群的性别组成,以雌雄混居最常见(占54.72%),其次为独居雄性(占20.95%),而褐扁颅蝠栖宿群雌雄混居群与独居雄性所占比例相当(均为40.63%)。2种蝙蝠的雄性趋向于独居,而雌性趋向于群居。扁颅蝠与褐扁颅蝠可以栖宿在同一片竹林内,并且可以在不同时间轮流使用同一个栖宿竹筒,但2种蝙蝠从未共栖于同一个竹筒内。另外,标记重捕扁颅蝠发现:扁颅蝠经常变换栖宿竹筒(栖宿竹筒不固定);同时栖宿群之间经常发生个体交换[动物学报50(3):326—333.2004]。  相似文献   

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11.
The expression of class II major histocompatibility complex (MHC) antigens on alveolar epithelial cells and macrophages was investigated immunocytochemically in paraquat-induced alveolitis in the rat lung. Until 2 days after paraquat injection, class II MHC antigens were expressed on the type II alveolar epithelium without any inflammatory cellular infiltration. From the 4th to the 7th day after paraquat injection, class II MHC antigen-positive macrophages increased in the alveolar spaces, whereas the expression on the type II alveolar epithelium became obscure. Over 10 days after the injection, interstitial fibrosis progressed and the intra-alveolar inflammatory infiltrates decreased. Epithelial cells lining the thickened fibrous septa no longer expressed class II MHC antigens. These results suggest that chemical stimuli can induce class II MHC antigen expression on the type II alveolar epithelium in the early stage of cellular injury, followed by inflammatory infiltration and interstitial fibrosis.  相似文献   

12.
The importance of proper lysosomal activity in cell and tissue homeostasis is underlined by "experiments of nature", i.e. genetic defects in one of the at least 40 lysosomal enzymes/proteins present in the human cell. The complete lack of 1-4 alpha-glucosidase (glycogen storage disease type II (GSD II) or Pompe disease) is life-threatening. Patients suffering from GSD II commonly die before the age of 2 years because of cardiorespiratory insufficiency. Striated muscle cells appear to be particularly vulnerable in GSD II. The high cytoplasmic glycogen content in muscle cells most likely gives rise to a high rate of glycogen engulfment by the lysosomes. The polysaccharides become subsequently trapped in these organelles when 1-4 alpha-glucosidase activity is absent. During the course of the disease, muscle wasting occurs. It is hypothesised that the gradual loss of muscle mass is caused by a combination of disuse atrophy and lipofuscine-mediated apoptosis of myocytes. Moreover, we hypothesise that in the remaining skeletal muscle cells, longitudinal transmission of force is hampered by swollen lysosomes, clustering of non-contractile material and focal regions with degraded contractile proteins, which results in muscle weakness.  相似文献   

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Tryfon  E.  Moustaka-Gouni  M. 《Hydrobiologia》1997,351(1-3):61-75
The phytoplankton of Lake Mikri Prespa was studied atmonthly or biweekly intervals during the period May1990–September 1992. Its species composition,consisting of a great number of cyanophytes and a verysmall number of chrysophytes and desmids, may reflectthe eutrophic character of the lake. Moreover, themean annual biomass values (15.0 and 3.2 g m–3 inthe two years, respectively) and the maximum biomass(38.1, 6.4 and 9.6 g m–3), classify Mikri Prespaas a eutrophic lake. A tendency towards adouble-peaked pattern of biomass distribution in timewith one peak in autumn, composed mainly ofcyanophytes, and another in spring made up of diatoms,was observed. This pattern contrasts with the standardpattern in eutrophic, stratified temperate lakes,which exhibit a third biomass maximum in summer.Cyanophytes were the most important group in terms ofbiomass and were dominated by the species Microcystis aeruginosa, Microcystis wesenbergii,Anabaena lemmermannii var. minor and Aphanocapsa elachista var. conferta. Diatomsconstituted the second most important group, with main representative the species Cyclotellaocellata. Cyanophytes, diatoms, chlorophytes anddinophytes revealed annual periodicity whereas theother algal groups did not show any seasonality atall.The nanoplankton constituted an important part ofalgal biomass (38.9 and 49.9% in the two years,respectively) and revealed annual periodicity withmaximum values in winter and spring, mainly composedof diatoms and cryptophytes. Low temperature,increased rainfall and high DIN concentrations seemedto be the main factors influencing the seasonality.Although the percentage contribution of nanoplanktondecreased with the increase in total biomass,justifying the classification of Lake Mikri Prespaamong the eutrophic lakes, the nanoplankton biomassdid not correlate significantly with totalphytoplankton biomass.  相似文献   

20.
The author is with the DSM-Deutsche Sammlung von Mikroorganismen und Zellkulturen GmbH, Mascheroder Weg 1b, D-3300 Braunschweig, Germany.  相似文献   

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