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From a survey of 30 species and varieties of ladybugs the presence of alkaloids appears to be correlated with the existence of aposematic colour and not with being carnivorous or phytophagous. The alkaloids described until now all belong to the Coccinellini and are closely related, but other types of bases have been detected in some genera. The observed distributions are in agreement with the modern taxonomy of the family.Ladybug alkaloids constitute an effective defence against ants, Myrmica rubra, and quails, Coturnix coturnix, but all the beetles containing alkaloids do not possess the same degree of protection. Individual quail react differently towards moderately protected species.The bioassay used for the first isolation of coccinelin is described. The repulsive activities of aqueous solutions of coccinellin and convergin towards ants have been compared.  相似文献   

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《Comptes Rendus Palevol》2002,1(6):439-448
The natural selection proceeds to very different time paces according to the hierarchical level of the observations. Two methods are used by palaeontologists for reporting how fast is evolution through geological time: the taxonomical and the morphological rates of evolution. However, the interpretation and the understanding of these rates of evolution are not easy. So, there were and still are many debates, and even controversies, concerning the tempo of the history of life as depicted by fossils. Examples from European Palaeogene fossil mammals illustrate some aspects of this problem.  相似文献   

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《Comptes Rendus Palevol》2002,1(7):615-627
Fossil invertebrates collected or received by Alcide d’Orbigny, all his life long, have been brought together in a renowned collection that is very rich in terms of both species and specimens. The collection has resulted from a huge palaeontological work. Study of faunas from numerous French sites led Alcide d’Orbigny to do biostratigraphical comparisons and to erect geological stages, the definitions of which rest on their stratotypes. His wide knowledge of European fossil faunas was strengthened by a more global palaeobiogeographical view derived from his travel in South America. The d’Orbigny collection is housed in the ‘Muséum’ of Paris and is often visited by experts.  相似文献   

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Results

26.2% of this population presented psychiatric disorders according to DSM-IV with a significant over-representation of generalized anxiety disorder and somatization disorder. The comparison between azoospermic males and oligoazoospermic males demonstrate the absence of significant difference in terms of psychiatric morbidity rate and use of defense styles. This population used similar defense modalities to the general population and preferentially used defense mechanisms corresponding to the mature defense style, such as humor, repression and anticipation. Psychiatric illness was significantly correlated with preferential use of withdrawal, consumption, reaction formation and lack of humor. This study also confirmed that subjects who essentially using neurotic defense styles were more likely to develop psychiatric disorders.

Conclusion

No difference in psychological effects was observed according to the degree of sterility. On the other hand, the presence of an over-representation of psychiatric disorders in sterile males compared to a control group indicates that Consultation-Liaison psychiatrists and andrologists must try to understand the patient’s suffering beyond the need for artificial insemination. Patients should therefore be given an opportunity to express all of the feelings related to their personal and marital drama in the department in which they are treated, as part of specialized management. Our study confirms the difficulty of determining whether certain defense mechanisms constitute risk factors for psychiatric disorders or whether defense mechanisms are an epiphenomenon of a particular psychiatric disorder, which is why many authors using DSQ agree that additional prospective studies are necessary to investigate correlations between defense mechanisms and specific psychiatric disorders. It would be useful to investigate defensive modalities before the diagnosis of infertility and after birth of a child in a larger population. A better understanding of the defensive modalities used by this type of population, in a psychotherapeutic context, could help to prevent or at least predict the appearance of psychiatric disorders.  相似文献   

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Le terme d’anticorps anti-nucléaires (ANA), consacré par l’usage, est trop restrictif puisque certains de ces anticorps reconnaissent des antigènes cytoplasmiques. Un très grand nombre d’ANA a été identifié au cours des 30 dernières années. Seul un nombre restreint de ceux-ci est spécifiquement associé à des maladies précises, connues sous le vocable de connectivites. Toutefois, des ANA peuvent assui être rencontrés dans d’autres affections, un syndrome infectieux ou inflammatoire, une néoplasie, une maladie spécifique d’organe, en particulier les maladies du foie comme l’hépatite auto-immune et certaines cholangiopathies. Enfin, il ne faut pas oublier l’apparition d’ANA survenant lors de la prise de certains médicaments. La spécificité de ces anticorps est tout à fait différente de celle que l’on observe dans les connectivites.  相似文献   

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Intraleft dyssynchrony is strongly correlated to contractile dysfunction associated to severe heart failure. Dyssynchrony is also a predictive marker for cardiac resynchronization therapy response. We measured dyssynchrony values for both ventricles from gated blood pool SPECT images.Material and methodsThree groups of patients were sampled from normal patients (n = 7), mild heart failure patients (n = 24) and severe heart failure patients (n = 9). Time-derivative parametric images were obtained from 24-time bins gated blood pool SPECT data. We measured intraleft and interventricular contractile and relaxing dyssynchrony values from these images.ResultsIntraleft dispersions values linked to ventricular peak emptying rate were 107 ± 21 ms, 141 ± 58 ms and 515 ± 104 ms for each of the three groups. The values linked to left ventricular peak filling rate were 122 ± 62 ms, 219 ± 117 ms and 603 ± 164 ms respectively. Statistical significant differences (p < 0.01) were observed both for contractile and relaxing phases for severe heart failure patients. Mild heart failure patients had isolated statistical significant (p < 0.01) alterations of the ventricular relaxing phase. Correlation between isotopic dyssynchrony values and left ejection fraction led to a R square coefficient of 0.71 and 0.64 for time to peak emptying and to peak filling respectively. Correlation to QRS width values led to a R square coefficient of 0.76 and 0.62 respectively.ConclusionVentricular dyssynchrony correlated to the importance of the ventricular mechanical dysfunctions is a robust predictor of heart failure. Separate analysis of contractile and relaxing dyssynchrony may lead to a better understanding and characterization of the mechanical dysfunctions involved in heart failure.  相似文献   

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Cet article est la première partie d’un dossier relatif à l’Automation et à la Robotique. Elle est plus théorique. Elle sera suivie d’une deuxième partie pratique, réalisée en lien avec des installations effectives.  相似文献   

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Since the first publication on the detection of sperm-agglutinating antibodies in infertile men, multiple assays have been described. The most useful tests are able to detect antibodies bound to the sperm membrane of motile spermatozoa. The immunobeads test (IBT) is considered to be the most advantageous in terms of its sensitivity, the low incidence of false-positive results, and its ability to localize antibodies of different immunoglobulin classes on the sperm surface. The IBT assay can be used in parallel with the mixed antiglobulin reaction (MAR), to detect sperm-associated antibodies in the ejaculates of infertile men, the most rational way to test for antisperm antibodies (ASA) in males. In view of the high level of agreement between the two assays, MAR, the easier of the two, may be used as a first step in the detection of these antibodies. A positive MAR must be confirmed by IBT, as this assay is more specific for the detection of IgA antibodies. The clinical significance of sperm-associated antibodies is usually established according to the proportion of motile spermatozoa coated with immunobeads, its class and its localization on the sperm surface. However, binding of immunobeads does not provide any information about the antigens against which the antibodies are directed. As the functional effects of sperm-associated antibodies may vary as a function of their antigenic specificities, other assays, using purified fertilization related antigens, are necessary to establish, for each individual, the specific impact of the antibodies on the fertilization process. The indirect IBT assay has recently become the most widely used test to detect the various classes of ASA in serum and cervical mucus of infertile women and in the serum and seminal fluid of infertile men, in combination with the direct assay described above. However, in most laboratories, it is performed with only one dilution of the biological fluid tested, usually a low dilution, so that antibody levels of no significance for fertility could be detected. This may explain a recente debate (Human Reprod, 1999) on the significance of ASA as a cause of infertility. At present, and in the absence of standardized assays able to identify the antigens involved in each individual immune reaction, antibody assays, as detected by the IBT assay, in the serum and/or genital secretions of infertile subjects might provide useful clinical guidance.  相似文献   

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Resume La fécondation est généralement interne chez les phoronidiens. La segmentation des ceufs est totale, egale (parfois légèrement inégale) et de type radiaire (avec quelquefois une apparence fortuite de segmentation spirale). La gastrula est formée par embolie. La bouehe derive de la zone blastoporale sans formation d'un vrai stomodeum. L'anus est mis en place par perforation de l'ectodersme et représente une néo-formation indépendante du blastopore. Le mesoderme est issu par proliferation cellulaire des regions antérieure et laterales de l'archentéron. Le protoccele est forme par des cellules mésodermiques se disposant le long de la paroi du lobe préoral. Le métaccele est issu probablement suivant les espèces d'une ou deux masses. La formation du mesoderme correspond á une variation de la méthode entéroccelique typique. Les phoronidiens doivent être considérés comme des deutérostomiens, d'après l'ensemble de nos résultats (voir aussi Emig, 1973).
Observations and discussions on the embryonic Development in Phoronida
Summary Internal fertilization (in metaccelom) generally occurs in Phoronida. The eggs are extruded to the exterior through the nephridia, shed freely into the sea-water or retained in the lophophoral concavity. The cleavage of phoronid eggs is total, equal (or subequal) and radial (with sometimes fortuitous appearance of spiral cleavage patterns). The gastrula is formed by emboly. The mouth is derived from the anterior remnant of the blastopore without a true stomodeum. The anus arises by perforation, as an independent structure of the blastopore. The mesoderm formed by budding originates as isolated cells proliferated from the anterior and lateral surfaces of the archenteron. In the preoral hood appears a protoccel by mesodermal cells lining the walls of the blastoccel. The trunk clom (or metaccel) of Actinotrocha originates from one or two posterior masses of mesodermal cells. It is possible that the mode of formation of this coelom varies in respect to the different species. The mesoderm elaboration is considered as a modified enteroccelous method.The acceptance of Phoronida as deuterostomes is regarded as the logical consequence of the present considerations (see also Emig, 1973): radial cleavage, origin of mesoderm by a derived enteroccelous method, trimetamerous actinotrocha.

Abbréviations des figures a anus - lp lobe préoral - ar archentéron - b blastoccele - ma mésoderme de la région anterieure de l'archentéron - ml mésoderme des régions latérales de l'archentéron - bl blastopore - mes cellule mésodermique - bo bouche - n ebauche des - n éphridiesect mesderme - s sophage - end endoderme - p protocle - est estomac - t ebauche des tentacules - g ebauche du ganglion nerveux - te tentacule - gn glandes nidamentaire - v vestibule - i intestin  相似文献   

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《L'Anthropologie》2022,126(5):103099
Collective burials were the main and most widespread funerary practice at the end of the Neolithic, beginning of the Bronze Age in the south of France. Megalithic monuments required a huge investment of time and labor. According to ethnographic studies, these monumental tombs are generally built and managed collectively. One can therefore wonder who was buried inside these structures because several archaeological studies indicate that access to these tombs can sometimes be restricted to certain members of the population. Indeed, ethnography highlights that access to certain tombs can be structured by variables such as kinship, social status, etc. While previous studies have mainly focused on the architecture and function of these monuments, this article focuses on the process of deposition of human remains and the characterization of the population buried inside these monuments. Since 2012, a project has been undertaken on the dolmens of the south of France in order to discuss funerary practices and to compare them with data from other archaeosciences to rediscuss the funerary traditions in place at the end of the Neolithic, the beginning of the Bronze Age.  相似文献   

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The tips of the rhizomorphs ofSphaerostilbe repens transferred on agar medium regenerate some aggregated organs without an intermediate mycelium stage. Each extremity of the drawn rhizomorphs can give rise to eoremia on its air face and to rhizomorphs on the contact with tho culture medium. These heterogeneous environmental factors impose polarized regeneration, easily inverted, upon the rhizomorphs. Nevertheless, a residual and stable polarity remains; it is attributed to the apex which is more capable of bearing new organs than the other extremity. Tho efficiency to regenerate depends on the ago of collulos and on tho size of tho rhizomorph tip; howover it is very difficult to provent the formation of new aggregated organs.  相似文献   

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When English marine Reptiles crossed the Channel. Mary Anning and Georges Cuvier, two actors of the discovery and study of Ichthyosaurs and Plesiosaurs. From 1800 to 1824, Georges Cuvier succeeded in obtaining a great deal of informations, as well as documents, drawings, casts and original fossils related to marine Reptiles (Ichthyosaurs and Plesiosaurs) from the Lower Jurassic (Lias) of Great Britain. He was completely informed about the discoveries made by Mary Anning. A great number of documents in the archives of the Museum national d’histoire naturelle in Paris show the importance and the quality of the scientific links that existed between France and Great Britain, in spite of the political vicissitudes between the two nations.  相似文献   

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