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1.
Résumé Nous avons essayé de faire élever des larves d'Anergates atratulus par des ouvrières deSolenopsis fugax (III) et des larves deLeptothorax nylanderi par des ouvrières deTetramorium caespitum (IV).III. Certaines des ouvrières deSolenopsis ont nourri une larve d'Anergates qui a grossi; les autres détruisirent toutes les larves d'Anergates qui leur furent confiées. D'autre part, une nymphe femelle d'Anergates introduite dans un nid deSolenopsis est parvenue au stade adulte.IV. 90 larves deLeptothorax ont été confiées à des ouvrières deTetramorium. 2 de ces larves ont atteint le stade adulte. Les 2 ouvrières deLeptothorax ainsi formées ont pondu des ufs, dont l'un se développa grâce aux soins d'une ouvrière deTetramorium.
Summary Larvae ofAnergates atratulus were experimentally given to workers ofSolenopsis fugax (III) and larvae ofLeptothorax nylanderi to workers ofTetramorium caespitum (IV).III. Some of the workers ofSolenopsis fed a larva ofAnergates which grew bigger; the others killed all the larvae ofAnergates that had been given to them. Moreover, a female pupa ofAnergates put into a nest ofSolenopsis, became an adult.IV. 90 larvae ofLeptothorax were given to workers ofTetramorium. 2 of these larvae became imagos. The 2 workers ofLeptothorax thus formed laid eggs, one of which was cared by a worker ofTetramorium and developed.
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2.
Résumé Nous avons fait élever des larves d'Anergates atratulus par des ouvrières deMyrmica laevinodis à 22°C. Pour y parvenir, il n'est pas utile de faire hivernerensemble les larves d'Anergates et les ouvrières deMyrmica. La présence de larves autochtones n'empêche pas lesMyrmica d'élever des larves d'Anergates. Dans toutes les expériences lesMyrmica ont été soumises au fridavant de recevoir des larves d'Anergates. Aucune reine deMyrmica n'a été utilisée dans ces expériences.Sur les 64 larves d'Anergates que nous avons utilisées, 38 se sont transformées en imagos. C'est au début de l'adoption et au moment des métamorphoses que périrent la plupart des 26Anergates perdus. Les femelles vécurent en général 2 ou 3 jours et cherchèrent très tôt à quitter le nid natal. Les mâles vécurent 2 à 3 semaines.
Summary Larvae ofAnergates atratulus were experimentally reared by workers ofMyrmica laevinodis, at 22°C. An overwintering of both larvae ofAnergates and workers ofMyrmica is not necessary for the success of that experiment. The presence of larvae ofMyrmica does not keep theMyrmica from rearing larvae ofAnergates. The workers ofMyrmica have been cooled, in all the experiments, before receiving larvae ofAnergates. No queen ofMyrmica have been used in that experiments.38 of the 64 larvae ofAnergates used became imagos. Most of the 26 lostAnergates died at the beginning of the adoption and during the metamorphosis. The females lived generally 2 or 3 days and tried, very early, to leave their native nest. The males lived 2 or 3 weeks.

Anergates atratulus Myrmica laevinodis, 22 . bmecme Anergates Myrmica. Myrmica Anergates. Myrmica Anergates. Myrmica . 64 Anergates , 38 . 26 Anergates 2 3 . 2 3 .
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Différentes analyses (histologie, spectrométrie infra-rouge, EDS, Chromatographie, etc…) ont été réalisées sur les phases organiques et minérales d’os venant d’Aubrelong 1 (Oligocène, Phosphorites du Quercy, France). Il apparait que la quantité de matière organique tend à diminuer au cours de la fossilisation. Les propriétés de la matière organique diffèrent nettement de celles de l’os frais: seuls les composés de faibles masses moléculaires sont présents. Les modifications de la composition chimique minérale de l’os fossile sont étroitement liées à celles du sédiment pour certains éléments. La comparaison avec les analyses d’os venant d’autres sites confirme une grande variété de comportement des éléments minéraux et organiques constitutifs, rendant prématurée toute tentative de dégager des conclusions concernant d’éventuelles corrélations avec l’age géologique, la diagenèse et le milieu de conservation.  相似文献   

5.
J. A. Sánchez  J. Rubio 《Genetica》1986,70(2):153-160
Evolution of enzyme polymorphism in experimental populations of Drosophila melanogaster III. Linkage disequilibrium between alleles of the Adh and -Gpdh loci — The evolution of gametic frequencies and linkage disequilibria between alleles of the Adh and -Gpdh-loci was followed in two experimental populations of Drosophila melanogaster maintained at different temperatures. The results observed were compared with those expected on the basis of theoretical models of gametic selection. Gametic fitness values were estimated from the analysis of the productivity of the different homozygous genotypes.Our experimental results indicate that the selection favours an association between the alleles Adh-F and -Gpdh-S, but it is impossible to generate and/or maintain a stable linkage disequilibrium between the two alleles.  相似文献   

6.
Résumé L'étude porte sur deux Desmidiées dont l'activité nitrate-respiratoire a déjà fait l'objet d'un travail précédent.On observe que les algues carencées en azote perdent leur activité nitrate-réductrice, tandis qu'elles utilisent des quantités de nitrite beaucoup plus grandes que dans les conditions expérimentales habituelles.En présence d'acide ascorbique, on note une modification fréquente, mais variable, des activités nitrate- et nitrite-réductrices. Les algues protègent cet acide et les nitrites contre une oxydo-réduction réciproque.Les algues étudiées semblent pouvoir utiliser, suivant les circonstances, différents systèmes énergétiques.
Summary Previous experiments (C. van der Ben, 1970) have shown that several species of Desmids are able to reduce nitrates to nitrites in vivo. This reducing property depends greatly on various environmental factors such as pH, temperature, light and nitrate concentration.The present paper analyses some conditions of this nitrate-reducing capacity, i.e. nitrate-respiration. The factors investigated are nitrogen-privation and action of ascorbic acid. It has been found that Staurastrum cultures deprived of nitrogen after exponential growth phase become unable to reduce nitrates but their nitrite-reduction is enhanced. The present observations show that algal suspensions protect ascorbic acid and nitrites against mutual destruction.In the presence of ascorbic acid, the nitrate- and nitrite-reducing activity of the algae is frequently and variably modified. Staurastrum and Cosmarium seem to have the ability to switch to various energetic sources according to environmental conditions.
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Routine evaluation of semen characteristics-spermiogram-includes estimation of the percentage of motile sperm; however it does not provide quantitative informations about sperm movement characteristics, except under the form of qualitative appreciations (slow, sluggish, yawing, non progressive, etc.). Flagellar function is indeed directly involved in the migration of spermatozoa through the female genital tract, and in the fertilization process by itself (migration through the zona pellucida requires special motility state, generally called “hyperactivation”). Sperm flagellar movements can now be indirectly investigated by analysing movements of sperm head, which are more easily detectable under phase contrast illumination: video signals are digitalized then sperm tracks are reconstructed by the computer from coordinates of sperm centroids (these systems are called “computer-assisted semen analysis” or “CASA”). CASA systems are now so performing and rapid that sperm movement analysis (SMA) can be proposed in the same time of routine semen analysis. However SMA, together with other functional tests, offer more interest in some particular situations as unexplained infertility, or unexpected failure of IVF. Numerous studies have tried to identify the most discriminant parameters, generally by means of multiple regression analysis. The interpretation of litterature data is difficult because of several differences in the protocol design, concerning either the measurements conditions (before or after sperm washing and selection) or the nature of the functional test: migration into cervical mucus, zona-free hamster egg penetration, IVF, etc. Moreover, the most discriminant factors are generally represented by classical parameters as % of normal forms or of motile sperm. In the present study we showed that only the factor “% of motility” allowed a significant discrimination according to different classes of fertilization rate (FR) in an IVF system. FR increased with hyperactivation rate (HA), but the statistical test was not significant. However, the more numerous cases of IVF failure were found in the group corresponding to very low HA rate (0–5%). We conclude that one major interest of SMA is to reveal some flagellar dyskinesia (i.e. corresponding to low values of amplitude lateral displacement of the head, or straight line velocity). These cases could then benefit of assisted reproductive techniques well adapted to this motion dysfunction, as subzonal insemination (SUZI) or intra-cytoplasmic sperm injection (ICSI).  相似文献   

9.
《Micron (1969)》1971,3(1):1-31
In the first section, various techniques are described for preparing pollen for study by scanning electron microscopy. The techniques include acetolysis, acid and basic hydrolysis, ultrasonic splitting of the exine, mounting and sectioning. The effects of the different treatments on the pollen are compared and summarized in a table which contains appropriate cross references to the illustrations provided. The second part is essentially a review of information obtained by these various techniques in the study of the exine and apertures of pollen grains of woody members of the Saxifragaceae.  相似文献   

10.
Résumé Les expériences d'hypercalcémie aigües et chroniques provoquent chez le rat des modifications spectaculaires des cellules C. Ces résultats sont en accord avec les données physiologiques sur la sécrétion de calcitonine chez le mammifère. Chez le poulet, par contre, les mêmes expériences ne provoquent pas de modifications indiscutables des Corps ultimobranchiaux (C.U.B.). Seule, l'injection intraveineuse de calcium provoque une dégranulation d'ailleurs partielle et assez peu accusée, des cellules C. L'inertie réactionnelle des C.U.B., que nous constatons morphologiquement, ressort également des données contradictoires sur le rôle physiologique de la calcitonine chez l'oiseau.
Influence of experimental modifications of calcemia on the fine structure of the C-cells in rat and in chicken
Summary Acute and chronic hypercalcemia in rats induce spectacular modifications of the C cells. These results are in agreement with the physiological data on calcitonin secretion in mammals. The same experiments in chickens, however fail to provide a net modification of the ultimobranchial body. Only an intravenous injection of calcium induces degranulation of the C cells, and even then, this is partial and hardly evident. The lack of the ultimobranchial body response as observed in our morphological study may be compared with the conflicting physiological data on the role of calcitonin in birds.
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11.
The cytotoxic agents used in cancer therapy cause serious and long lasting side effects on spermatogenesis in young male patients. In absence of prophylactic measures (cryoconservation of Spermatozoa prior to therapy; lead shields during radiation therapy; drugs less damaging to spermatogenesis), the use of protective agents is necessary. Numerous antioxydants and a variety of hormones have been experimented in attempts to limit the deleterious effects of antimitotic drugs. Major animal studies have been conducted into ?rtain GnRH analogs, FSH steroïds, and in particular the combination of Medroxyprogesterone Acetate + Testosterone, leading to encouraging results. Progress in animal experimentation should, within the near future, allow clinical trials in humans.  相似文献   

12.
Résumé Un marquage à l'or radio-actif de butineuses deFormica polyctena a été effectué le long d'une piste de butinage. Nous avons constaté que les échanges de nourriture étaient très faibles entre ouvrières travaillant sur des pistes différentes.
Summary Labelling foraging ants (Formica polyctena) with radioactive gold on a foraging path, the authors observe that the exchange of food are very weak between foragers from differents paths.


Ce travail est dédié au Pr. KonradLorenz, pour son soixantième anniversaire.  相似文献   

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14.
X-Ray diffraction studies have been carried out on some lipids of various chemical compositions: two monoglycerides (glyceryl-monodecanoate and glyceryl-monododecanoate), several phospholipids (synthetic di-palmitoyllecithin, egg lecithin, lysolecithin derived from the latter, egg phosphatidylethanolamine) and sphingolipids (sphingomyelin and cerebrosides isolated from beef brain) have been studied. The structure of these lipid-water systems depends on concentration and temperature: crystalline phases are formed at low temperatures, whereas higher temperatures and high lipid content promote the formation of liquid-crystalline phases. At low lipid content and high temperature, only lysolecithin forms a micellar solution in water; for the other lipids, a suspension of a liquid-crystalline phase in excess water is observed.Four liquid-crystalline phases, already described in other soap or lipid systems, have been observed here.
  • 1.(a) A lamellar phase occurs in the following systems: water-monoglyceride (monodecanoate: 25 °C; monododecanoate: 45 °C); water-sphingomyelin (45 °C); water-cerebrosides (72 °C); water-phosphatidylethanolamine (20 °C); water-egg lecithin (5 to 35 °C) and anhydrous lecithin at high temperature.
  • 2.(b) A hexagonal phase, made of a regular array of lipid cylinders, is observed in the water-lysolecithin system at 35 °C.
  • 3.(c) An inverted hexagonal phase (cylinders made of water) occurs in the water-phosphatidylethanolamine system at 55 °C.
  • 4.(d) A cubic phase is observed in anhydrous lecithin at high temperature.
The structural parameters of these phases and the polymorphism of the various lipids are discussed.  相似文献   

15.
Résumé Une rickettsie entomopathogène:Rickettsiella grylli proche des chlamydies par son cycle de multiplication est introduite chez la souris par voie nasale et par voie buccale. La rickettsiose expérimentale produite est étudiée sous les aspects clinique, anatomopathologique, sérologique et histologique. Les rickettsies sont recherchées dans les tissus par immunofluorescence et microscopie électronique. Chez les souris infestées par voie nasale, les rickettsies restent localisées dans les poumons. Lors des contaminations fortes, ces derniers subissent une hépatisation et une bronchopneumopathie se développe; cette pneumopathie se maintient pendant eviron 2 mois puis évolue, dans de nombreux cas en une bronchopneumopathie chronique durant plus d'un an. Les souris élaborent des anticorps agglutinants spécifiques dont le taux est proportionnel à l'atteinte pulmonaire. L'infestation par voie buccale ne détermine aucun effect pathologique à court ou long terme.
Summary Rickettsiella grylli Vago & Martoja is a rickettsial entomopathogen close to the chlamydia by its multiplication cycle. This organism has been inoculated in mice by intranasal and oral routes. The experimental rickettsiosis has been studied by the clinical syndromes, anatomopathology, serology, histology, immunofluorescence and electronic microscopy. By inhalationR. grylli is localized in lung tissues. In heavy contaminations the lungs present hepatisation and a bronchopneumopathy that last 2 months and evolves to a chronic bronchopneumopathy in 50 % of the tested mice. Agglutinin type antibodies are produced and their concentration are proportional to the severity of the lung infection. No short term or long term pathological effects are detected by oral administration.
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Résumé Afin d'étudier les effets de l'acidité lors de la fécondation chez l'Omble de fontaine, la motilité des spermatozoïdes, l'absorption d'eau par les oeufs et la survie de ceux-ci ont été déterminées à différents pH. Les poissons fournissant les gamètes utilisés pour ces tests provenaient de lacs acides ou non acides.Pour les valeurs de pH inférieures à 5,0, la proportion de spermatozoïdes motiles diminue rapidement et devient nulle à pH 3,0. A pH 4,0, cette proportion est plus élevée dans une solution d'acide sulfurique, qui est totalement dissocié, que dans une solution d'acide acétique, faiblement dissocié. Dans cette dernière, la quantité d'ions H+ neutralises par le sperme est environ cinq fois plus élevée que dans la solution d'acide sulfurique.La pression osmotique du milieu de fécondation ainsi que l'origine des géniteurs, provenant de lacs acides ou non, affectent également la résistance des spermatozoïdes.L'absorption d'eau par les oeufs est diminuée à pH 5,2 ou 4,5 selon l'origine des géniteurs. La survie des oeufs est peu affectée pour des pH de 4,5 et plus, mais est réduite à pH 4,0.L'ensemble des résultats permet d'avancer qu'un pH de 4,5 représente la limite inférieure compatible avec une bonne fécondation chez l'Omble de fontaine; cette limite semble cependant susceptible d'être modifiée par la présence d'acides faibles dans le milieu et par l'origine des géniteurs.
Variations in acidity were shown to have pronounced effects on the gametes of Salvelinus fontinalis collected from populations living in acid or circum-neutral lakes.Spermatozoa motility was reduced at pH less than 5.0 and ceased at pH 3.0. Within this range, motility was greater in the presence of strongly dissociated acid (H2SO4) than in a weakly dissociated one (CH3COOH). In the latter solution, at pH 4, sperm neutralized 5 times as many H+ as in the former. Differences in spermatozoa motility were observed depending upon the origin of the gametes and the osmotic pressure of the medium.Egg survival was reduced at pH 4. Water absorption by eggs decreased below pH 5.2 or 4.5 for eggs collected from circumneutral or acid lakes, respectively.These results suggest that pH 4.5 represents the lower limit for successful fertilization of eggs of brook trout, the precise point depending upon the types of acid present and the origin of the parental stock.
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18.
In Locusta migratoria direct experimental and infrastructural data confirm correlations between the fate of post-imaginal prothoracic glands and corpora allata activity.The presence of juvenile hormone in haemolymph during metamorphosis and corpora allata hyperactivity allow the prothoracic glands to persist. Cyclic activity of these glands is synchronous with ovarian cyclic activity. These physiological conditions are obtained by isolation, short day-length, high relative humidity, by CO2 periodic anaesthesis (1 min by day), or experimentally by the implantation of supernumerary active corpora allata. These conditions also produce the solitaria form.The absence of juvenile hormone in the haemolymph during the first three days of adult life, or precocious corpora allata ablation, prevents prothoracic gland degeneration.The prothoracic gland shows some chief cytological features during the first three imaginal days (‘periode de latence’). Thus, lytic structures with phosphatase acid activity always appear and suggest, according to Wigglesworth's hypothesis, that a cerebral degenerative factor is liberated during metamorphosis. This factor is inhibited by juvenile hormone and the prothoracic glands persist.  相似文献   

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《Médecine Nucléaire》2020,44(5-6):320-325
Radiosynoviorthesis is used for the local treatment of recurrent joint effusions and leads to synovial pannus necrosis after radionuclide administration. This procedure provides the opportunity to full recovery of normal synovium function after local corticosteroids and systemic modifying drugs failure.  相似文献   

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