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1.
<正>广东南岭地区蝙蝠多样性较为丰富,2000年后发表的9种广东蝙蝠新纪录中即有5种采集于南岭(吴毅等,2001,2005;张燕均等,2010;周全等,2011,2012;陈毅等,2013)。2013年7月21日,我们在保护区动物资源调查过程中,于广东南岭国家级自然保护区八宝山保护站(北纬24°55'43.4″,东经113°0'57.0″,海拔1 000 m)附近的路上夜晚挂网捕捉到一批蝙蝠  相似文献   

2.
本研究扩增了169号鼠兔属样本的cyt b序列,代表13个种11亚种及5个未分类单元,下载了66条分类地位确定而完整的Cyt b序列,包括25种及9个亚种。构建了Bayesian系统发育树,计算了遗传距离,开展了物种界定分析;对13个种4亚种及5个未分类单元174号完整头骨和外形的20个形态学量度数据开展了主成分分析、判别分析和T检验;对头骨和身体外部特征进行了比较研究。结果显示:鼠兔属包含5个亚属,分别是Ochotona, Conothoa, Pika, Lagotona 和一新亚属;5个亚属间的遗传距离在12.8%-16.0%之间;高黎贡鼠兔(Ochotona gaoligongensis)是灰颈鼠兔(O. forresti)的亚种;喜马拉雅鼠兔(O. himalayana)是灰鼠兔(O. roylei)的亚种;木里鼠兔(O. muliensis)是川西鼠兔(O. gloveri)的亚种;宁夏鼠兔(O. argentata)应为蒙古鼠兔(O. pallasi)的亚种;西伯利亚鼠兔(O. turuchanensis) 为高山鼠兔(O. alpina)的同物异名。藏鼠兔循化亚种(O. thibetana xunhuaensis)应提升为种:循化鼠兔(O. xunhuaensis);东北鼠兔长白山亚种(O. hyperborea coreana)应该提升为种:长白山鼠兔(O. coreana);藏鼠兔峨眉亚种(O. thibetana sacraria)应提升为种:峨眉鼠兔(O. sacraria); 藏鼠兔锡金亚种(O. thibetana sikimaria)应提升为种:锡金鼠兔(O. sikimaria)。通过分子系统学和形态学研究,发现了鼠兔属1 新亚属和5个新种。新亚属命名为异耳鼠兔亚属(Alienauroa subgen. n.),属模为黄龙鼠兔(O. huanglongensis sp. n.),成员包括黄龙鼠兔新种、峨眉鼠兔、循化鼠兔,以及在龙门山和大巴山发现的2个新种,共计5个种。新亚属的鉴定特征是:耳上前缘内侧有一个密被短毛的异耳屏(Congenial tragus);头骨扁平,颅面平直;眼小,眼眶长和眼眶宽均小于其他亚属;被毛粗长而无光泽;腹毛多为灰白色。5个新种分别发现于四川黄龙自然保护区、四川北部龙门山、四川北部大巴山、四川西部邛崃山、西藏雅鲁藏布江中游的朗县。我们分别将其命名为黄龙鼠兔(Ochotona huanglongensis sp. n.),扁颅鼠兔(Ochotona flatcalvariam sp.n.),大巴山鼠兔(Ochotona dabashanensis sp. n.),雅鲁藏布鼠兔(Ochotona yarlungensis sp. n.)和邛崃鼠兔(Ochotona qionglaiensis sp. n.)。黄龙鼠兔的鉴定特征是:门齿孔前段平行;脑颅扁平,颅高为颅全长的33.5%;耳大,平均20mm以上(不含耳基部的管),异耳屏三角形,但顶端圆形;毛长而粗糙,无光泽,背部毛长约20mm;腹面毛色以灰白为主;前后足背面灰白色,腹面黑灰色,指(趾)垫大,橘黄色,露出毛外,爪黄白色半透明。扁颅鼠兔的鉴定特征是:脑颅异常扁平,颅高约11mm,颅高仅为颅全长的31%;眼眶很小,平均6.7mm×5.6mm;个体小,体长140mm以下;体毛长而粗糙无光泽,背部毛长22mm;耳小,平均17mm左右,异耳屏阔圆型,相对较小;背毛沙黄色,腹毛黄白。大巴山鼠兔的鉴定特征是:异耳屏镰刀状;耳相对较小,均在17mm以下,和峨眉鼠兔、扁颅鼠兔差不多,比该亚属循化鼠兔和黄龙鼠兔小。颅高相对较大,颅面更隆突,颅高平均12.45mm, 眼眶相对较大,平均8.52mm×7.13mm。雅鲁藏布鼠兔的鉴定特征是:与黑唇鼠兔(O. curzoniae)和努布拉克鼠兔拉萨亚种(O. nubrica lhasaensis)有很近的亲缘关系;唇缘有很窄的深灰色圈,深灰色圈外侧为灰白色;前后足底部毛浓密,趾端毛多而长,趾垫和爪隐于毛中;个体中等,体长150mm左右,比黑唇鼠兔和努布拉克鼠兔拉萨亚种小得多;颅面较隆突,但与黑唇鼠兔相比,颅面相对平直;被毛黑褐色。邛崃鼠兔的鉴定特征是:大小及头骨和藏鼠兔很相似,但该种和藏鼠兔的显著不同是眶间宽狭窄,平均4.05mm(3.64-4.19mm),而藏鼠兔眶间宽一般超过4.2mm,平均为4.45mm;该种毛色为沙色带黄色调,毛粗长;藏鼠兔为黑褐色调,毛相对较短;邛崃鼠兔前后足背面为显著的草黄色,而藏鼠兔前后足背面黄白色。  相似文献   

3.
The mechanics of anchorage in seedlings of sunflower, Helianthus annuus L.   总被引:2,自引:0,他引:2  
Forces applied to plants will subject many of the roots to tension, which must be transferred to the soil via shear if uprooting is to be prevented. The stress distribution will depend on the relative stiffnesses of the earth and root, and the mode of failure will depend on the relative strength of the soil and of the root soil bond. This study of the anchorage of sunflower radicles combined uprooting tests performed by a tensile testing machine with mechanical tests on the roots and soil.
The maximum extraction force increased with length to an asymptotic value and was reached at a very low displacement. Root hairs and soil particles covered the tapered top 20 mm of extracted root, but the lower cylindrical region was bare. The soil was stiffer than the root, so shear stress was initially concentrated at the top of the root, soil strength over the top 20 mm resisting uprooting. Lower regions of the root were stressed later, their sparser root hairs being sheared off, and resist uprooting only by friction. In a further lest upper and lower regions of radicles were uprooted separately. As predicted, the upper region generated much greater resistance to uprooting per unit length, and at much lower displacements than the lower region.
The top of the radicle is well adapted for anchorage, the profuse root hairs and mucigel it produces glueing the root to the soil. The lower regions are thus protected from damage.  相似文献   

4.
Gametophytes of the fern family Thelypteridaceae were cultivated aseptically under controlled conditions and investigated with the scanning electron microscope. This report concerns six species, viz. Sphaerostephanos arbuscula S. subtruncatus, S. unitus, Macrothelypteris torresiana, Amauropelta hakgalensis and Pneumatopteris truncata . The gametophytes have some features in common. They are more or less heart-shaped and have glandular trichomes on surfaces and margins. In the middle is an elongated cushion bearing gametangia and rhizoids on the lower surface. Antheridia are of the type common to leptosporangiates, consisting of a basal cell, a ring cell and a cap cell. Archegonia consist externally of four rows of cells meeting at the top with triangular cells. The following features are distinguishing. The form of the margin of the thallus, type of hairiness, and the abundance of glandular hairs. Acicular hairs occur in Sphaerostephanos unitus and Pneumatopteris truncata . In Amauropelta hakgalensis the archegonium deviates from the common type in having a basal layer that consists of eight cells instead of four. In Macrothelypteris torresiana the four or three top cells are markedly irregular. In Sphaerostephanos arbuscula and Amauropelta hakgalensis the antheridial cap cell is sometimes divided. The manner of opening of antheridia and release of spermatozoids varies in each of the species investigated. This investigation reveals that it is possible to identify the species from gametophyte characters only.  相似文献   

5.
中国翼手类新记录--小巨足蝠   总被引:6,自引:0,他引:6  
2003年9月在云南获得1号雌性蝙蝠标本,经鉴定为中国新记录——小巨足蝠(Myotis hasseltii),标本保存在中国科学院动物研究所。  相似文献   

6.
Various changes appear in hair by aging, and graying is the most remarkable one. Changes in melanocytes have been well studied as the cause; however, little is known about the change in melanosomes which have a role of carrying melanin pigments into hair shafts. Using pigmented hairs of Japanese females from their age of 4–75, I isolated melanosomes and observed them. As a result, I found a significant change in the morphology of hair melanosomes with age. They were ellipsoidal on the whole and there was no age dependence in the major axis, while the minor axis significantly increased and its frequency distribution broadened with age. The anticipated volume of the melanosome of the oldest person hairs was about twice larger than that of child hairs. This enlargement of melanosome seems to be a cause of the age‐related color change in pigmented hairs from brown to black.  相似文献   

7.
目的了解过敏性结膜炎患儿常见过敏原及其分布特征,为预防和脱敏治疗提供依据。方法采用免疫印迹法对363例过敏性结膜炎患儿进行血清过敏原检测,并对结果进行分组比较。结果患儿中检出率居前3位的吸入性过敏原分别为尘螨(50.41%)、猫毛(3.03%)和霉菌(2.48%);检出率居前3位的食物性过敏原分别为淡水鱼(10.74%)、海鱼(7.44%)和鸡蛋白(6.34%)。吸入性过敏原(62.26%)和食物性过敏原(41.60%)总检出率比较差异有统计学意义(P0.05)。婴幼儿组、学龄前组和学龄组患儿均以尘螨为常见过敏原,其检出率分别为33.33%、52.76%和52.00%。不同年龄患儿牛奶过敏检出率比较差异有统计学意义(P0.05),婴幼儿组牛奶过敏检出率最高,为12.82%。男、女患儿过敏原阳性率比较差异无统计学意义(P0.05)。不同年龄患儿过敏原阳性率比较差异无统计学意义(P0.05)。婴幼儿组、学龄前组和学龄组患儿均以单纯吸入性过敏原和单一过敏原为常见。1月-3月为儿童过敏性结膜炎的低发季节。结论通过血清过敏原检测可明确过敏性结膜炎的过敏原。尘螨是本地区儿童过敏性结膜炎常见过敏原。  相似文献   

8.
Seventy-seven lower auricular malformations in 74 patients treated during the last 6 years were analyzed. Sixty cases (77.9 percent) were of malformations involving the earlobe; 54 cases involved the earlobe alone, and 6 cases were of complex deformities involving the earlobe and adjacent helix and/or tragus. Cleft earlobe was the most common lower auricular malformation (49 cases, 63.6 percent); four subtypes and their corrective methods are described. Cases of complex earlobe malformations, corrected by fabricated costal cartilage and expanded skin flap, are presented. A question mark ear (5 cases, 6.5 percent), a malformation with an ectopic anthelical fold (5 cases, 6.5 percent), and a malformation with a lower conchal stria (5 cases, 6.5 percent) are considered to be major lower auricular malformations. An attempt has been made to correlate the presented malformations with the embryologic-fetal development of the auricle. It is suggested that "clefting" ear malformations such as the cleft earlobe, the question mark ear, and the ectopic anthelical fold deformity may provide clues to understanding the embryologic-fetal development of the human auricle. It appears that hillocks 1 and 6 produce the earlobe and that hillock 4 or 5 produces the anthelix or helix.  相似文献   

9.
1.  Filiform hairs of various lengths on the cerci of adult crickets vibrate in a sound field. These movements were measured with a photodetector for sound frequencies from 10 Hz to 200 Hz in the species Acheta domestica, Gryllus bimaculatus and Phaeophilacris spectrum.
2.  With low air-particle velocities, the hair shafts were deflected sinusoidally from their resting position, without bending or secondary oscillations (Figs. 2 A, 3 A). At higher velocities (from ca. 80 mm/s peak velocity, depending on the properties of the individual hairs), the shaft struck the cuticular rim of the socket in which the base of the hair is seated (Fig. 2B). This contact was made at an average angular displacement from the resting position of 5.16°±1.0°.
3.  The best frequencies of the hairs were found to be between 40 Hz and 100 Hz (Fig. 5A). The slope of the amplitude curve for constant peak air-particle velocity at frequencies below the best frequencies was between 0 and 6 dB/octave. Long hairs had smaller slope values than short hairs (Fig. 5C).
4.  At its best frequency the ratio of maximal tip displacement of a hair to the displacement of the air particles in the sound field was between 0.2 and 2. Only a small number of hairs (2 out of 36) showed tip displacements exceeding twice the air-particle displacement. The values of maximal angular displacement were not correlated to hair length (Fig. 5 B).
5.  The angular displacement of the hairs was phase shifted with respect to the air-particle velocity by 0° to +45° (phase lead) at sound frequencies around 10 Hz and by -45° to -120° (phase lag) at 200 Hz (Figs. 3C, 4B). At a particular frequency long hairs tended to have larger phase lags than shorter hairs (Fig. 5D).
  相似文献   

10.
It was established previously that helical propensities of different amino acid residues in the middle of α‐helix in peptides and in proteins are very similar. The statistical analysis of the protein helices from the known three‐dimensional structures shows no difference in the frequency of noncharged residues in the middle and at the C terminus. Yet, experimental studies show distinctive differences for the helical propensities of noncharged residues in the middle and in the C terminus in model peptides. Is this a general effect, and is it applicable to protein helices or is it specific to the model alanine‐based peptides? To answer this question, the effects of substitutions at positions 28 (middle residue) and 32 (C2 position at the C terminus) of the α‐helix of ubiquitin on the stability of this protein are measured by using differential scanning calorimetry. The two data sets produce similar values for intrinsic helix propensity, leading to a conclusion that noncharged amino acid residues at the solvent‐exposed positions in the middle and at the C terminus of the α‐helix have the same helical propensity. This conclusion is further supported with an excellent correlation between the helix propensity scale obtained for the two positions in ubiquitin with the experimental helix propensity scale established previously and with the statistical distribution of the residues in protein helices.  相似文献   

11.
It has been described that the frequency ranges at which theta, mu and alpha rhythms oscillate is increasing with age. The present report, by analyzing the spontaneous EEG, tries to demonstrate whether there is an increase with age in the frequency at which the cortical structures oscillate. A topographical approach was followed. The spontaneous EEG of one hundredand seventy subjects was recorded. The spectral power (from 0.5 to 45.5 Hz) was obtained by means of the Fast Fourier Transform. Correlations of spatial topographies among the different age groups showed that older groups presented the same topographical maps as younger groups, but oscillating at higher frequencies. The results suggest that the same brain areas oscillate at lower frequencies in children than in older groups, for a broad frequency range. This shift to a higher frequency with age would be a trend in spontaneous brain rhythm development.  相似文献   

12.
蚤类感觉板的细微结构   总被引:2,自引:1,他引:1  
本文利用扫描电镜观察了4科18属26种蚤的感觉板.通过对其内、外表面及横断面细微结构的详细观察,发现前人称之为杯陷的结构,实为一中空的圆丘,分内、外两层,各具若干小室,作者称其为感觉室.该室在感觉板上具有一定的分布型.感觉毛着生于内室底部,通过中央孔及外室顶孔向外伸出.蚤类成虫具有坚韧的外骨骼,因此,在制备扫描电镜标本时可不经特殊处理直接进行观察.此外,对感觉室的功能及在分类上的意义进行了讨论.  相似文献   

13.
Summary Mechanical oscillation properties of cricket (Acheta domesticus) filiform hair sensilla were measured at different larval stages, as an indication of larval sensory capacities and for comparison with data in the literature on central nervous changes during development. The hairs were stimulated by airborne vibration over a frequency range of 10 to 220 Hz. Best frequency, angular displacement at best frequency, slope of angular-displacement tuning curve and phase of hair deflection relative to air particle velocity were tested for correlation with hair length, which is proportional to the age of a sensillum. The ranges found for the various oscillation parameters in early larval stages were similar to or larger than those in adults. Oscillation properties changed with both the developmental stage of the hair sensilla and that of the whole animal. Four individually identifiable hair sensilla were analysed separately; the sensory neurons of two of them are known to change synaptic properties during maturation. Angular displacement at a given stimulus intensity was maximal for all hairs after differentiation, and decreased during further development. The hairs did not show clear common changes for any of the other oscillation parameters. Yet particular changes were found for individual hairs.  相似文献   

14.
The pollen-collecting hairs (PCHs) of Campanula have been a subject of intense debate for the past two centuries. Although several morphological studies have been made on these hairs, detailed comparative studies among species are still lacking, their function and adaptive significance being an unsolved question. The present study comprises two microscopy techniques: scanning electron microscopy and confocal scanning laser microscopy. The aim of the present study is to elucidate: 1) the variation in morphology of the PCHs, 2) the variation in presence/absence of the PCHs by the time of spreading of the stigmatic lobes, 3) the variation in the retractive mechanism of the PCHs, and 4) the correlation between pollination and the retraction of the PCHs. In several species PCHs of various lengths are found. Despite the variations in length of the hairs, the same retractive mechanism is found in all species studied. In most species the hairs retract into basal cavities within the style late in anthesis. The cells into which the hairs retract differ in length among species. Pollen grains are often found within the cavities together with the retracted hairs, a mechanism considered to prevent self-pollination. Pollen germination within the cavities was not observed. In a few species, the PCHs are still present at stigma receptivity. Differences in the shape and size of the cells surrounding the PCHs are documented. The diameter of the pits and the pollen grains vary among species. Other types of hairs on the style are recognized in some species, being of various lengths. These other types do not retract at stigma development and should not be regarded as pollen-collectors. They possibly facilitate for visiting insects to reach the nectar glands, present at the top of the ovary.  相似文献   

15.
Arachnids and insects use long, thin hairs as motion sensors to detect signals contained in the movement of the surrounding air. These hairs often form groups with a small spacing of tens to hundreds of micrometers between them. For air oscillation frequencies of biological interest, the potential exists for viscosity-mediated coupling among hairs in a group affecting their response characteristics. Even a small diameter hair can, in principle, affect the flow field around it and the dynamics of the hairs in its neighborhood. The viscosity-mediated coupling between a pair of hairs is investigated here both experimentally and theoretically. The conditions for the existence of the coupling effect, and its magnitude as a function of relevant parameters, are determined. In the range of biologically relevant frequencies (30–300 Hz), viscous coupling between pairs of hairs is only very small in the case of the spider Cupiennius salei. Theoretical analysis points to the relatively large spacing between hairs (20 to 50 hair diameters) and the tuning of the hairs to the above-mentioned frequencies to explain the practical absence of coupling.  相似文献   

16.
We studied the hair-forming ability of epithelium and the relevant activity of dermal papilla (DP) in mouse vibrissal follicles during the hair cycle. Follicles were transversely cut into four pieces and each of them was associated with an isolated DP and grafted beneath the kidney capsule to induce hair formation. Various hair-cycle combinations of the fragments and DPs were examined. Hairs were generated not only in the follicle fragment containing the bulge (fragment III) but also in the fragment between the bulge and hair bulb (fragment II). The hair-forming frequencies were affected by the hair cycle stages of both the follicle fragments and DPs. Fragment III at late anagen (LA) and fragment II at catagen frequently generated hairs when associated with early anagen (EA)-DPs, but infrequently with mid-anagen (MA)-DPs. Oppositely, anagen fragment II produced hairs at a high frequency with MA-DPs and at a low frequency with EA-DPs. Hair generation in anagen fragment II is an unexpected finding because previous studies suggested that, during anagen, this region does not contain clonogenic epithelial cells that have been believed to be crucial for hair formation. Therefore, non-clonogenic epithelial cells would be able to generate hairs as well as clonogenic ones, and they should have a latent hair-forming ability that could be more effectively awakened by MA-DP than by EA-DP stimuli. Non-clonogenic epithelial cells might be a dormant phase of hair precursor cells. Proliferating follicular epithelial cells were detected in the middle and lower outer root sheath throughout the hair cycle but scarcely at LA. These findings suggest that the hair inductivity of DPs should be altered between EA and MA, and follicular epithelial cells would change their DP stimuli-directed hair-forming ability around LA, probably linked to the proliferative activity.  相似文献   

17.
Captive colonies of cotton top tamarins experience a high rate of rejection of infants within the 1st week of life. The rates of rejection and survival to maturity (2 or more years) among 659 live colony-born infants were correlated with rearing, birth group, litter size, season of birth, gender, origin of parents, experience of parents raising siblings, parity and age of parents, and experience of parent pairs. The most important factors associated with low rejection rates were family life and parental experience raising infants. Infants born into family groups or reared in families were rejected at a significantly lower rate. Rejection of infants whose sires were raised with siblings was significantly lower. Paternal experience was more important than maternal experience. Litter size had no effect on rejection of infants born to family groups, whereas, rejection of triplets was significantly higher than twins or singles among those born to parents alone. Rejection was significantly higher among primiparous births than multiparous birth. The combined experience of colony-born parents was not related to rejection if there were no sibling helpers in the cage at the time of birth. Rejection was significantly lower if sibling helpers were present. High survival of infants who were not rejected was correlated with rearing by or being born into family groups and higher parity and older age of the sires.  相似文献   

18.
黄姗  杨韩  苏春  常朝阳 《西北植物学报》2018,38(9):1646-1658
采用体视显微镜和扫描电子显微镜,对中国产黄耆属糙叶组34种植物的叶表皮毛状体的形态特征及其分布进行了观察,以探讨中国黄耆属糙叶组物种表皮毛微观形态的变异式样及其分类学意义,为糙叶组物种的分类鉴定提供依据。结果表明:除乳白花黄耆(A. galactites)仅在叶下表面被毛外,其余种类上下表皮均有毛,且毛的分布、形态、长度和臂比在不同种类间存在差异。叶表皮毛为伏贴或开展的中空管状毛,伏贴毛着生部位基部膨大,整体形态从中部向两端由粗逐渐变细,开展的毛大部分为细长的丝状或线状,光滑或具条纹状纹饰,上面分布有乳突。研究认为,叶表皮表面伏贴、短而平直、其上光滑具密集乳突、臂比值小、整体宽扁的毛是祖先特征;而叶表皮表面向上开展、长而密集、外形呈丝状或线形、其上具条纹状纹饰、乳突稀疏、臂比值大的毛是进化特征。  相似文献   

19.
包文美  敖志文 《植物研究》1998,18(4):407-413
在室内培养条件下,详尽地比较观察了我国东北产的岩蕨科2属4种的配子体发育过程,了解该科在配子体发育上的特征,来说明建立岩蕨科的合理性和种属间的区别。  相似文献   

20.
The use of noninvasive collected samples as source of DNA in studies of wild primate populations has increased in recent years. Fresh‐plucked hairs represent an important source of DNA, with relatively high quality and concentration. In this study, we describe a low‐cost noninvasive technique for collecting fresh‐plucked hairs used to obtain DNA samples from free‐ranging black howler monkey populations (Alouatta pigra). We designed and manufactured darts made of wooden dowels, with the anterior part smeared with glue, which were projected with blowpipes to trap howler monkey hairs. All of the materials to make the darts are inexpensive and are available locally. We collected 89 samples from 76 individuals residing in 15 troops, and the total number of hairs obtained was 754. We found no differences in the number of hairs collected among sex–age classes or among localities but the percentage of darts recovered with sample varied among localities. Preliminary results indicate that over 96% of samples yielded DNA suitable for polymerase chain reaction‐based microsatellite marker analysis. The technique proved successful for collecting fresh‐plucked hairs of free‐ranging black howler monkeys without any trauma to the animals and can be easily adapted to obtain samples from other wild primate and mammal species. Am. J. Primatol. 71:359–363, 2009. © 2009 Wiley‐Liss, Inc.  相似文献   

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