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Louis Deharveng 《Chromosoma》1982,85(2):201-214
Polytene chromosomes in the salivary glands of Bilobella aurantiaca are analysed in a population from Sierra de Gredos (Central Spain). They display a high degree of heterozygosity. Only a short part of the total length of the seven pairs of homologous chromosomes, examined in a single favourable specimen, was homozygous. Concerning the short arm of chromosomes III and IV, the respective proportion of heterozygosity for the whole population was 38.6% and 92.9%. Some hypotheses are formulated to account for these results: differential funtioning of homologous chromosomes, generalisation of minute duplications and deficiencies, complex inversions (which cannot be specified owing to the asynapsis of homologous chromosomes), and possibly local large deletions. 相似文献
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Bernard Dutrillaux Marie-Odile Rethoré Marguerite Prieur Jérome Lejeune 《Human genetics》1973,20(4):343-354
Summary Prometaphasic chromosomes of Gorilla, Homo and Pan are compared, using R, Q, T and H-bands techniques in complement of a previous work (Lejeune et al., 1973). Various mechanisms of chromosomal rearrangements are demonstrated with particular reference to heterochromatic segments. Some phylogenic conclusions are proposed.
Travail de l'E.R.A. no 47 du C.N.R.S. 相似文献
Zusammenfassung Prometaphase-Chromosomen von Gorilla, Mensch und Schimpanse werden mit hilfe der R-, Q-, T- und H-Bandentechnik verglichen; frühere Arbeiten (Lejeune et al., 1973) werden dadurch ergänzt. Verschiedene Mechanismen von Chromosomen-Rearrangements werden dargestellt; dabei finden die Heterochromatin-Segmente besondere Beachtung. Einige phylogenetische Folgerungen werden gezogen.
Travail de l'E.R.A. no 47 du C.N.R.S. 相似文献
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Christian C. Emig 《Zoomorphology》1977,87(2):147-153
Resume Trois types de parois ont été décrits dans l'appareil circulatoire du tronc dePhoronis psammophila. La succession des diverses couches de chaque type est la suivante: 1. cellules péritonéales — lame basale — rares cellules endothéliales; 2. cellules myoépithéliales — lame basale — rares cellules endothéliales; 3. une couche de muscles circukires, puis une de muscles longitudinaux — épaisse lame basale — endothélium continu.
Abréviations C capillaire - ce cavité coelomique - ce cellule endothéliale - cm cellule myoépithé'liale - cp cellule péritonéale - fc fibre musculaire circulaire - fl fibre musculaire longitudinale - gs globule sanguin - lb lame basale - m myofibrille - mf myofilament - tvp tissu vasopéritonéal - V vaisseau sanguin 相似文献
On the wall structure of the circulatory system inPhoronis psammophila Cori (Phoronida, Lophophorata)
Summary Three types of wall structure of blood vessels have been described. It consists of the following distinct layers, from exterior to interior: 1. peritoneal cells — thin basal lamina — some endothelial cells; 2. myoepithelial cells resting on a basal lamina — some endothelial cells; 3. circular and longitudinal muscle layers of myoepithelial cells — thick basal lamina — continuous endothelial lining.
Abréviations C capillaire - ce cavité coelomique - ce cellule endothéliale - cm cellule myoépithé'liale - cp cellule péritonéale - fc fibre musculaire circulaire - fl fibre musculaire longitudinale - gs globule sanguin - lb lame basale - m myofibrille - mf myofilament - tvp tissu vasopéritonéal - V vaisseau sanguin 相似文献
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José G. Palacios Vargas Enrique García‐Barros José C. Simón Benito 《Cladistics : the international journal of the Willi Hennig Society》2010,26(5):482-496
In order to assess the phylogenetic structure of the springtail genus Palmanura, as well as to test the monophyly of the tribe Sensillanurini (Neanuridae: Neanurinae), a data matrix of morphological (chaetotactic and other) characters of members of this group was assembled and analysed in the light of Wagner parsimony. The data matrix included all the known members of the Neotropical genus Palmanura, plus representatives of Sensillanura and Americanura. Although not all the clades obtained were highly supported by bootstrap resampling, some structures were relatively constant under different approaches. Alternative analyses (unordered and ordered character states, rescaled weighting procedure) were applied. While alternative solutions were obtained, a number of structures were shared by the results irrespective of the method used. On this basis, the results suggest that some further reassessment is required to confirm formally the monophyly of the tribe Sensillanurini. The genera Palmanura and Americanura are mutually poly/paraphyletic; we thus suggest that Palmanura should be considered as a synonym of Americanura, although some character reassessment and more varied outgroup species may be necessary before a formal generic redefinition can be proposed. Finally, a comparison of the performance of the characters under Wagner parsimony analysis indicated that differences in the characters’ retention indexes are due not to the topological (tagmal) position of the traits involved, but to character coding: the characters describing quantitative features (generally numbers of setae) generally performed worse than other types of characters under parsimony. An updated list of the known members of the Sensillanurini (Collembola: Neanuridae: Neanurinae) is presented.© The Willi Hennig Society 2009. 相似文献
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Paul Cassagnau 《Chromosoma》1974,46(4):343-363
In the Collembolan Neanura monticola (2 n ♀ = + XX, 2 n ♂ = 12 + XO) only the autosomes have classical polytene structure in salivary glands. — In a valley of the Pyrenees-mountains, the X-chromosome shows an intense polymorphism with 13 different types of pattern. These differences are revealed in the pairing in bundles of elementary fibres, in the apparition of transversal bands, in a progressive overcharge of α-heterochromatin in certain points, briing a radiant structure of chromosome (25 differents types of heterogametic females have been observed). — In the damp forests at lesser altitude, the X-chromosome remains flaky, as in polyploid nuclei of other tissues. The structure with parallel bundles appears in cold forests between 1 600 and 1 800 m of altitude. In subalpine biotopes the astral-ray type becomes preponderant and from 2 200 m the exclusive form with hypertrophy of α-heterochromatic block. Various hypothesis are discussed that explain the selective advantage an α-heterochromatic overcharge might give to the subalpine populations. 相似文献
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Three new species of Endonura are described from Iran. Endonura
dichaeta sp. n. can be recognized by an ogival labrum, head without chaetae O and E, chaeta D connected with tubercle Cl, tubercle Dl with five chaetae on head, absence of tubercles Di on thorax I and tubercle (Di+Di) of thorax V with 2+2 chaetae. Endonura
ceratolabralis
sp. n. is characterized by large body size, reduction of labral chaetotaxy, ogival labrum, head without chaeta O and fusion of tubercles Di and De on first thoracic segment. Endonura
persica sp. n. is distinguished from its congeners by a nonogival labrum, absence of chaeta O, tubercles Dl and (L+So) with five and eight chaetae respectively and claw with inner tooth. The key to all species of the genus is given. 相似文献
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Samples collected in “restinga” areas of two conservation units in Rio de Janeiro state revealed the presence of two new species of Neanuridae family. The first, Pseudachorutes solaris sp. nov., from Parque Estadual da Costa do Sol and from Parque Nacional da Restinga de Jurubatiba, differs from other species for having 34–50 vesicles in the postantennal organ, and the second, Friesea jurubatiba sp. nov. from Parque Nacional da Restinga de Jurubatiba, differs from other species for having 8 clavate chaetae in the abdominal segment VI. 相似文献
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对颚毛虫兆属Crossodonthina Yosii, 1954做了简要介绍,提供了该属的鉴别特征,记述了采自中国湖南省东安县舜皇山的颚毛虫兆属1新种——周氏颚毛疣虫兆Crossodonthina choui,这是该属在华中地区(湖南)的新记录。新种的正模标本(♂)和2个副模标本(2♂)保存在中南林业科技大学生命科学与技术学院昆虫标本室。 相似文献
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Two new species of Neanurinae (Collembola) are described from the Western Cape, South Africa: Ectonura monochaetasp. n. and Ectonura barraisp. n.Ectonura monochaetasp. n. differs from other species in the genus by its strongly reduced chaetotaxy, and the lateral shift of dorso-internal chaetae on Abd. V and their integration in the tubercles (De+DL). Ectonura barraisp. n. is similar to Ectonura natalensis (Womersley, 1934), but differs in chaetotaxic details and chaetal group arrangement. A key to the seven species of Neanurinae recorded from South Africa is given. 相似文献
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《International Journal of Insect Morphology and Embryology》1987,16(3-4):245-261
The fine structure of the tibiotarsal and pretarsal sensory organs of Monobella grassei banyulensis Deharveng (Collembola : Neanuridae) has been examined by electron microscopy.Three types of sensory organs have been observed. (1) the most numerous setae of the tibiotarsus are classic mechanosensitive setae with one bipolar sensory cell, whose distal outer segment ends in a tubular body. (2) Two small setae are arranged on each side of the basal part of the claw; they show 3 sensory cells, 2 of which are mechanosensitive cells of the scolopidial type; the outer segments of the 2 mechanosensitive cells end at the base of the sensory hair. The dendrite of the 3rd sensory cell extends into the hair shaft. (3) Two similar chordotonal sensilla link the tibiotarsus and the pretarsus; each sensillum is composed of 2 bipolar sensory cells enveloped in sheath cells. The first type of sensory organ shows the characteristics of insect exteroceptive mechanosensitive hairs. The mechanosensitive cells of the 2nd and 3rd tibiotarsus sensory organs are probably proprioceptive and control the movements of the pretarsus in relation to the tibiotarsus. Two features are noteworthy: (1) the association of the scolopidial cells with a chemosensitive one has never been observed in other insect sensory organs, except in the Collembola; and (2) there is an important morphological diversity in the ciliary roots of the various scolopidial cells, which are in other respects very similar. 相似文献
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A new species of Pseudachorutes is described and illustrated from Nicaragua. Pseudachorutes nicasp. n. is very easy to distinguish from other members of this genus from Central America, because its chaetotaxy consists of macro and microsetae and a postantennal organ with multiple vesicles (close to 20). 相似文献
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J. F. David Ferreira 《Cell and tissue research》1961,55(1):89-103
Résumé Dans cette étude on met en évidence la propriété phagocytaire des plaquettes pour des substances étrangères. Les observations ont été faites sur des coupes de tissu pulmonaire de lapins injectés par voie endoveineuse avec du dioxyde de thorium colloïdal et sur des plaquettes humaines isolées et mises en contact in vitro avec du dioxyde de thorium colloïdal.La possibilité de la participation des plaquettes sanguines dans la défense de l'organisme contre certains agents est admise.Le mécanisme de la phagocytose du thorotrast est décrit et on explique l'origine d'une partie · des éléments du granulomère . L'auteur admet aussi l'hypothèse que les éléments du granulomère décrits par Schulz et coll. (1958) soient le résultat de la phagocytose des substances étrangères par les plaquettes.A propos des observations réalisées sur les plaquettes humaines isolées in vitro l'auteur décrit des granules de 230 Å possédant en son intérieur des granules de 30 Å très évidents dans les coupes traitées à l'acetate d'uranyl.Avec la collaboration technique de Mme. Karin David Ferrbira. 相似文献
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Corrélations simples (r) et pondérées (rp)entre S. setosa (trois stades cumulés), S. minima etS. inflata (stade 1), S. bipunctata, et les quatre paramétreshydrologiques retenus. aSeuil de signification 5%. bSeuil designification 1% 相似文献
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Résumé La fixation osmiée et l'étude ultrastructurale permettent de préciser que les grosses vacuoles intraneuronales des cellules du N.S.O. de la Souris, qui apparaissent après une surcharge osmotique prolongée, ont un contenu lipidique.
Dédié amicalement à Madame le Professeur Berta Scharrer, avec nos très respectueux hommages.
Attachée de Recherches au C.N.R.S.
Collaboratrice technique. Travail réalisé dans le cadre de la R.C.P. No 39 du C.N.R.S. 相似文献
Summary Fixation with Palade's fluid and ultrastructural study reveal that after prolonged ingestion of hypertonic saline, the vacuoles in the Cells of the supraoptic nuclei of the Mouse contain lipid droplets.
Dédié amicalement à Madame le Professeur Berta Scharrer, avec nos très respectueux hommages.
Attachée de Recherches au C.N.R.S.
Collaboratrice technique. Travail réalisé dans le cadre de la R.C.P. No 39 du C.N.R.S. 相似文献
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