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1.
本文对棉铃虫片Helicoverpa armigera(Hubner)雌雄外生殖器的一般构造和超微结构进行了较细致的研究。并与其近缘种作了比较研究。结果表明:在一般形态方面,棉铃虫种群内个体间变异较大,种群间分化较小:在雄性阳茎端囊的弯折数、大刺数及抱器瓣的长宽比等特征上与近缘种间有一定的重叠。在超微结构方面,种群内个体间、种群间均变异不大,但与近缘种间在雄性阳茎端囊刺构造上却有明显的、间断的差异,这一差异为近缘种的鉴别 提供了新的、可靠的特征。  相似文献   

2.
种间电子传递可促进微生物发生共代谢,因而在地球生物化学循环和环境污染修复中具有重要意义。根据电子传递方式的不同可将种间电子传递分为直接种间电子传递(direct interspecies electron transfer,DIET)和间接种间电子传递(mediated interspecies electron transfer,MIET),其中,直接种间电子传递由于易发生、效率高而受到更加广泛的关注。本文总结了近年来关于种间电子传递的研究进展,阐述了种间电子传递的途径,比较了DIET和MIET的优缺点,并对开发更多具有种间电子传递功能的微生物提出了建议,以期加深人们对于种间电子传递的理解,并对未来该领域的研究提供参考。  相似文献   

3.
本文根据营养动力学理论,建立了一类种间竞争的新的数学模型:它是单种群增长的Cui-Lawson模型,在种间竞争上的推广。新的种间竞争模型克服了经典的种间竞争的Lotka-Volteira方程的局限与不足,具有更广泛和复杂的行为,并在特殊条件下以Lotka-Volterra竞争方程为其特例。因此,新的种间竞争的数学模型是更一般的解释性模型,是对经典的Lotka-Voterra竞争方程的扩充。  相似文献   

4.
蕺菜属不同居群间比较解剖学研究   总被引:13,自引:1,他引:12  
杨玉霞  吴卫  郑有良 《广西植物》2003,23(5):429-435
对采自四川、重庆、江苏等地蕺菜属的 2 5个不同居群间进行了较为全面的比较解剖学研究。结果表明 :蕺菜属不同居群间的根、地上茎、地下茎、叶等器官在解剖结构上存在较大差异。但峨眉蕺菜与蕺菜解剖结构的种间差异不明显。文中还对蕺菜属不同居群间解剖结构差异与质量间关系进行了探讨。  相似文献   

5.
采用2×2列联表,通过Pearson积矩相关系数和Speaman秩相关系数对黑石顶森林次生演替过程中各阶段群落优势种的种间协变进行了定量分析。结果表明,在演替初期的裸地恢复阶段,显著种间协变的种对较多,有14对(正协变9对负协变5对),在针阔混交林阶段,显著种间协变的种对较少,仅有5种。全为正协变,表现为主要种间对群落环境的相同要求,并形成了主要种间的竞争格局,在阳生性常绿阔叶林阶段。显著种间协变的种对最少,只有4对,其中3对为负协变,这是主要种之间对群落环境相同要求的激烈竞争结果,在中生性常绿阔叶林阶段,显著种间协变的种对最多有20对,19对为正协变,主要表现为群落上层种和中下层种间形成了大量的正协变,但群落上层主要种间无显著的种间协变。  相似文献   

6.
采用 2× 2列联表 ,通过方差分析、χ2检验、Ochiai指数对黑石顶森林次生演替过程中各阶段群落优势种的种间联结性进行了定量分析。研究结果表明 :群落的总体种间关联性在演替恢复初期表现为无相关性 ,针阔叶混交林阶段为总体的正关联 ,阳生性常绿阔叶林阶段呈总体负关联 ,中生性常绿阔叶林阶段总体呈显著正关联。在演替初期主要种对间尚未形成一定的种间关系 ,演替至混交林和阳生性常绿阔叶林阶段 ,种间关系开始形成 ,但大多表现为直接的竞争关系 ,中生性常绿阔叶林阶段形成了复杂多样的种间关系 ,表现为同层树种间的种间结合或竞争和不同层种间的结合关系  相似文献   

7.
团头鲂肌间骨发育的形态学观察   总被引:3,自引:0,他引:3  
研究利用整体骨骼染色、形态学解剖和X光透射的方法, 对团头鲂(Megalobrama amblycephala)仔稚鱼肌间骨的出现时期、形态以及成鱼肌间骨数目、形态、分布和长度变化进行了观察与分析。结果表明: 团头鲂的肌间骨在孵出后20d (体长为1.33 cm)骨化出现, 首先出现在尾部, 然后向头部方向依次出现, 到第40天(体长为2.36 cm)基本全部出现; 肌间骨出现与分化的时间受生长发育的影响大于日龄的影响。团头鲂肌间骨数目在108129, 平均为119 根, 其中躯干部轴上肌中的肌间骨数目最多(4045根), 尾部轴上肌与轴下肌中的肌间骨数目相近(3239根)。肌间骨形态包括1形、卜形、y形、一端多叉形、两端多叉形和(形6种类型, 各种形态的肌间骨均是从1形发展而来; 肌间骨越靠鱼体前端形态越复杂。团头鲂躯干轴上肌中的肌间骨显著长于尾部肌肉中的肌间骨(P 0.05), 躯干轴下肌中的肌间骨最短, 并且肌间骨长度与个体体重与体长呈正相关。研究结果为今后揭示团头鲂肌间骨发生与发育的分子机制, 抑制团头鲂肌间骨骨化, 培育无肌间骨的团头鲂提供了形态学基础。    相似文献   

8.
远缘杂交是指亲缘关系在种间及种间以上的生物之间的杂交,它可以使基因组从一个物种转移到另一个物种中,从而导致杂交后代的表现型和基因型都发生改变.如果远缘杂交后代两性可育,则可以通过自交繁衍形成遗传变异的品系,它们在生物进化、遗传和育种方面具有重要作用.本文在分析和归纳大量国内外有关动物远缘杂交文献的基础上,结合本实验室长期从事鱼类远缘杂交的研究结果,对动物远缘杂交研究的最近概况及其相关问题进行了较全面综述,其中介绍了动物门间、纲间、目间、科间、亚科间、属间和种间的杂交状况,阐述了鱼类远缘杂交品系的形成规律和遗传变异特性及它们在生产上的应用等.本文在生物进化和动物遗传育种方面具有意义.  相似文献   

9.
野生和近交稀有鮈鲫的遗传多样性   总被引:10,自引:0,他引:10  
用RAPD技术对稀有鮈鲫近交10代及3个野生群体的遗传多样性和群体间差异进行了研究。无论从多态位点的比例、个体间的共带率还是从多样性指数来看,近交10代的遗传多样性极低。在226个RAPD位点中,野生群体有近半数的位点是多态的,Shannon多样性指数在0.2911~0.3235间,表明自然群体保持了较丰富的遗传多样性。近交10代与野生群体间遗传差异十分明显。野生群体间在11~19个位点上的表型频率存在显著差异,总遗传多样性的91.33%来自群体内,8.67%来自于群体间。  相似文献   

10.
吴立甫 《人类学学报》1984,3(4):365-371
本文报告了450例布依族和410例仡佬族的12项皮纹正常值测定,在左右手间和男女性间进行了比较,并以汉族作为对照。  相似文献   

11.
The scarcity of information on control data of toe and plantar dermatoglyphics led us to undertake this study of adult American Caucasians. Toe and sole prints of 168 male and 83 female participants of the Baltimore Longitudinal Study of Aging were analyzed. Toe pattern frequencies demonstrate that fibular loops are the most prevalent pattern on the toes in both males and females. Pattern distribution by digit shows that arches are most often located on the fifth toe while whorls are found with greatest frequency on the third toe. Plantar pattern frequencies indicate that the most common pattern found in the hallucal area is the distal loop. Open fields are frequently found in the II and IV interdigital areas while distal loops are prevalent in the III area. These results are compared to the finger and palmar patterns of the same individuals. The distribution of patterns on the toes and fingers of the same individuals appear to be quite different. Population comparisons did not demonstrate a clear racial difference in the toe pattern frequencies or in the plantar areas.  相似文献   

12.
Dermatoglyphic analyses were carried out on a sample of children with known sex chromosomal aneuploidies (25 XXY, 10 XXX, 1 XXYY). Digital ridge counts and pattern types were determined for each individual. Palm prints and sole patterns were also examined. The results of our study were compared with data from previous studies of sex chromosomal aneuploidies. Our results for the XXY males agree with the findings from other studies with respect to total ridge counts and plantar dermatoglyphics, but not for digital pattern frequencies. Our one example of an XXYY male showed hypothenar patterns similar to those found for this syndrome by other researchers, but neither the digital pattern types nor the unexpectedly high total ridge count conforms to the findings from other studies. Our sample of XXX females falls within the normal XX female range of variation with respect to hypothenar patterns and total ridge count; plantar features show a higher incidence of patterns than previously reported.  相似文献   

13.
The finger and palmar prints of a total of 386 individuals (182 males and 204 females) at an age between 10 and 18 years from the region of the villages Petkovo and Banite, situated along the river Malka Arda in the Central Rhodopes, were studied. The following dermatoglyphic traits were analyzed: pattern intensity index (PII), the main line or Cummin's index (MLI), the frequencies of the proximal palmar triradius (t), the true hypothenar patterns (Hy) and the accessory interdigital triradii (AIT). The specific dermatoglyphic complexes after Heet were also determined for the population under study. A peculiarity of this population is the appearance of a clearly expressed Eastern Complex (EC), which accounts for 53.1% in the males and for 48.8% in the females. These values of EC and the calculated dermatoglyphic distances (DD) after Heet show a similarity between the examined population and a number of populations from the Volga region, Northern Caucasus, Middle Asia and Siberia. This similarity could be explained with the preservation of the genetic heritage of the proto-Bulgarians, one of the three main components of the modern Bulgarians.  相似文献   

14.
罗桐秀  许名宗  周祥  李石旺 《遗传》2001,23(3):220-222
本研究对猴和人的手(脚)掌纹进行了观察,并应用χ2检验进行比较分析,结果显示:(1)指(趾)间区、小鱼际区、脚弓区纹型出现频率,猴远远高于人。猴指(趾)间区纹型出现频率达95.5%以上,而人的指间区最高的Ⅰ4为72.1%,最低的Ⅰ1仅为1.0%,趾间区fⅠ3为34.6%,fⅠ1是3.7%;猴的手掌小鱼际区纹型频率为131.8%,脚掌小鱼际区为59.1%,而人分别为14.4%和18.5%;脚弓区也类似。(2)上述区的纹型类型,猴与人也有明显差异。最明显的特点是猴的斗形纹频率明显高。如指间区、趾间区、手掌小鱼际区和脚掌小鱼际区的斗形纹频率分别是77.3%、40.9%、59.1%和22.7%,而人分别为0.1%、0.3%、0和0。本研究结果对研究灵长目皮纹的遗传与进化有重要意义。 Abstract:Dermal ridges of palms (soles) in monkeys and men were observed.Using the method of χ2 examination to make a comparative study and analysis.The results showed the ridge pattern frequencies of the monkeys i n their interdigital areas were much higher than men.The ridge pattern frequenc y of the monkeys in each interdigital area and sole interdigital area was over 9 5.5%,but men’s Ⅰ4 was 72.1% at the highest, and Ⅰ1 was only 1.0% at the l owest, fⅠ3 was 34.6% and fⅠ1 was 3.7%.The ridge pattern frequency of the m onkeys in their hypothenars of palms was 131,8%,soles was 59.1%,but that of men were 14.4% and 18.5%.These similar phenomenon also existed in the arch areas of the feet.There were obvious differences between monkeys and men in their types o f ridge patterns.The obvious character was that the whorl frequency of the monke ys was obviously higher. For example ,the whorl frequency of the monkeys in thei r interdigital areas and sole interdigital areas ,hypothenar of the palms and so le were 77.3% and 40.9%,59.1%and 22.7% respectively.But those of the men were 0. 1% and 0.3%,zero and zero.The results are very significant for researching the i nheritance and evolvement of the primates'dermal ridges.  相似文献   

15.
Summary: In a sample, comprising 264 right-, 246 mixed- and 360 left-handers (RH, MH and LH, correspondingly), the atd-angle, the a-b ridge count and the hypothenar radial arch were investigated, the asymmetry of both quantitative traits differentiated into directional (DA) and fluctuating (FA) one. Except for the FA of the a-b ridge count in females, which decreased significantly from RH to LH, the trends observed in the relations between the investigated dermatoglyphic values and handedness were not significant. In both quantitative traits the most important finding was the categorical left-palm excess over the right palm, since it was significantly related to sex and handedness, being much more expressed in females than in males and in the non-right-handers than in the right-handers. The hypothenar radial arch, along with its considerably higher frequency in females than in males and on the right palm than on the left, as well as its rarity combined with a very high symmetry, displayed another interesting peculiarity. The pattern was 3.9-fold more frequent in the MH and 3.4-fold more frequent in the LH as compared to RH. As witnessed by the odds ratio, if a given palm belongs to a non-right-hander, the probability that it bears a hypothenar radial arch is nearly 4-fold higher than if it were a palm of a right-hander. Arguments are adduced that left-handedness, although not a pathological character is, to say the least, a modified condition and that, similarly, the hypothenar radial arch is a subnormal dermatoglyphic finding. If such is the case, their relationship found by the present study is not surprising, although its causal background still remains unclear.  相似文献   

16.
Hypothenar radial arch was found in 2.07% of the males and 2.82% of females in a sample of 2,130 Bulgarians. Persons bearing the pattern on the right hand display the highest frequency, followed by those bearing the pattern bilaterally and those with it on the left hand. A well-expressed tendency of the hypothenar radial arch towards symmetrical occurrence was disclosed through the ratio between the actual and expected frequency of its bilateral occurrence. This ratio is recommended as an efficient estimator of tendency toward symmetry. The presence of the pattern is associated with morphological peculiarities of the other dermatoglyphic features of the palm. Line A ends at two parts of the palm periphery which are extremes of its usual distribution. Line D is shortened and the ridges run more vertically than in palms without the pattern. The connection of the hypothenar radial arch with the border ulnar triradius, along with the observations on the opposite hypothenars in the unilateral cases, provides a support of Wilder's conception concerning the mode of formation of the pattern. A genealogical tree exhibiting transmission of the pattern over three consecutive generations is presented. A pattern of dominant inheritance with a fairly reduced penetrance is compatible with the genealogical data.  相似文献   

17.
本文报告了安徽省亳州地区400例 (男女各200人) 回族健康人的皮纹参数正常值。调查分析了指纹类型、指嵴纹计数、掌嵴纹计数、主线止区、atd角、t距比、掌褶和掌部花纹类型等项参数。比较了不同性别、左右侧、不同民族和人种间的差异。结果表明,回族有自己的手纹特点,又显示蒙古人种的一般特征。  相似文献   

18.
The patterns of age change in dental arch breadths and depths were studied longitudinally in Australian Aboriginals, 92 males and 68 females. Three types of change in relative arch dimensions were recognized: a divergent pattern in which the differences between maxillary and mandibular dimensions increased with age, a convergent pattern in which the differences decreased, and a parallel pattern in which the arch differences remained metrically stable. The feature that best distinguished the Aboriginals from Caucasian groups was the high frequency of subjects, 71% of males and 40% of females, who showed a divergent growth pattern. The association between divergent growth in arch breadths and the development of alternate intercuspation, which is characterized by an inability to occlude the teeth on both sides of the arch at the same time, is discussed.  相似文献   

19.
一千例甘南藏族手纹学分析   总被引:3,自引:1,他引:2  
杨金荣 《人类学学报》1983,2(2):157-161
本文报道1000例甘南藏族手纹学正常值。各类指端纹型按出现频率的多少依次为:尺箕(Lu)、斗形(W)、双箕(Wd)、桡箕(Lr)、弓形(A)、帐弓(A~t)。掌褶正常型占74.45±0.97、通贯手占8.15±0.61、总指嵴数168.10±51.54、a—b嵴数34.95±8.92、atd角(度)39.18±4.36。  相似文献   

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