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Résumé Des extraits de la surface d'œufs de Pyrale du ma?s ont été testés en microenceinte et dans un olfactomètre linéaire sur des ♀♀ deTrichogramma maidis. En microenceinte, les extraits stimulent la locomotion et le comportement exploratoire des ♀♀. En olfactomètre ils stimulent à distance la remontée des tubes vers la source. Ces résultats impliquent la présence de substances à activité kairomonale sur les œufs de Pyrale du ma?s. Des analyses préliminaires des extraits ont été faites par chromatographie en phase gazeuse couplée ou non à la spectrométrie de masse et démontrent la présence de nombreux hydrocarbures.
Summary Extracts from the surface of eggs of the European corn borer were tested in small observation chambers and in a linear olfactometer for their effects on the searching behaviour of the egg-parasitoidTrichogramma maidis. In the observation chambers, the extracts elicited exploratory behaviour by female parasitoids with no previous oviposition experiences and increased the time the females spent in walking and drumming their antennae. Recording the position of 10 ♀♀ each minute for 15 min in 2 tubes of an olfactometer, indicated that upwind motion was significantly greater in the tube containing 10 μl of an egg extract than in the control tube containing just solvent. It is concluded that kairomones are present onO. nubilalis eggs and could act as searching incitants and short-range attractants. Preliminary GC and GC/MS analysis revealed the abundance of hydrocarbons in the extracts but the active chemicals were not characterized.
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Clermont H  Douce R 《FEBS letters》1970,9(5):284-286
Mitochondria and plastids isolated from various plant tissues by methods which exclude contamination by other cell organelles lack phospholipase D activity.  相似文献   

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Conclusions Cette étude du fonctionnement ovarien nous a notamment permis d'évaluer quantitativement les principales variables du phénomène, ce qui était, dans notre programme de travail, à résoudre en première urgence.Nous avons montré l'importance de l'ovosorption dont nous connaissions l'existence sans pouvoir lui attribuer une valeur quantitative.Nous noterons une différence avec le Dytique: la dégénérescence peut frapper les ufs mûrs.D'un point de vue plus général, nous mettons en évidence dans une même fonction, la dualité des caractères entre les phénomènes de comportement marqués par leur grande variabilité et leur discontinuité, et les phénomènes physiologiques qui expriment sans rupture l'action des facteurs externes.Le fait qu'une certaine proportion des ufs produits puisse ne pas être pondue, permet d'expliquer la diminution ou l'augmentationbrusque de la ponte sous l'action de stimulations d'origine sociale, dues soit à l'évolution normale du nid (cellules libres, couvain, etc.), soit, plus fréquemment dans nos conditions d'expérience, à l'effet de groupe.
Summary Ovarian function inPolistes is governed by three fundamental parameters:the delivery rate of the ovaries, the duration of oocyte development, andthe rythm of egg-laying. The first two, which act directly upon the ovaries (particularly the number of developing oocytes), are immediately influenced by the physical environment, especially the temperature. The third, on the other hand, is under behavioral control.It is emphasized that the late parameter rarely attains its maximum value: the female does not lay all her eggs, eliminating a variable proportion by ovosorption.
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Like in many nuclear medicine centers, the AFSSAPS decision of November 25, 2008, has slightly changed our habits. The centers with medical physicist already made most of these controls, and this concept was not new for them. But what about the other centers? Sometimes, measures were made as expected, other times the manufacturers were expected to do them during the maintenance time, often nothing was formalized, and even in some cases nothing was done. Our experience in quality control in nuclear medicine is relatively recent, but we find interesting to raise some issues, including the duration for all these controls, the possible delegations, the means necessary to build them and difficulties in applying these controls.  相似文献   

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Joussier  Danielle  Catroux  G. 《BioControl》1976,21(3):223-225
Résumé Un milieu de culture permettant d'isoler et de dénombrer les colonies deBeauveria tenella parmi d'autres champignons du sol a été mis au point en vue de faciliter l'étude du comportement d'un germe entomopathogène artificiellement introduit pour lutter contre les pullulations des larves du Hanneton commun.
Summary A culture medium composed of 8 vegetable juices, glucose, yeast extract, dried oxgall and antibiotics (actidione, streptomycine, tetracycline) allows the isolation ofBeauveria tenella blastospores or conidiospores artificialy introduced in soil when the concentration of this inoculum varies between 100 and 40,000 spores per gram.
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[18F]-Fluoro-2-Deoxy-D-Glucose-Positon Emission Tomography (PET) is a powerful tool which availability increases in France. The oncological PET indications are plentiful and are increasing. Yet, its cost is significant. Thus, it is important to use PET in validated indications and/or in situations in which it can improve the patient management. The first part of this work reviews the PET indications in oncology, according to the international clinical practice guidelines (European Society for Medical Oncology [ESMO] and National Comprehensive Cancer Network [NCCN]), and compares those with the French guidelines (Guide de bon usage [GBU] des examens d’imagerie médicale). The second part assesses the indication distribution of 400 consecutive PET-CT studies in an against cancer center, according to the cancer type and confronts those with the guidelines.  相似文献   

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《L' Année biologique》1999,38(3-4):149-168
Tropical arboreal ants are distributed in a mosaic pattern in the canopy of forests and tree crop plantations each of them characterised by their status of dominance. One can distinguish ‘dominant’ species, characterised by extremely populous societies and highly developed interspecific as well as intraspecific territorial behaviour. They tolerate on their territory nonterritorial and less populous species classified as ‘non-dominants’. Nonetheless, many species do exist whose status is intermediary. Usually, they behave like non-dominant species but are able, under certain conditions, to defend a territory. They are cited as ‘sub-dominant’. According to the chemical trapping method employed by researchers, the structure of mosaics have most often been studied using an index of dominance, characterised by the number of negative or positive associations between one species and the others. This index only covers the relative presence or absence of the different species on the same trees. It only gives a punctual statement on the structure of the mosaic without any notion of evolution of the mosaic in time. It does not take into account the behavioural intra- and interspecific interactions. Aggressive interactions between species depend on genetic and environmental factors. Many studies have shown that aggressiveness is closely related to a mechanism of interindividual discrimination, permitting an individual to discriminate between nestmates and non-nestmates. This colonial recognition is based on the existence of a ‘colonial odour’ as a result of a blending of ‘individual odours’. Each individual odour is due to cuticular hydrocarbons which play the role of a contact pheromone. The colonial odour also depends on the environmental odour of the nest. Aggressiveness which results from this mechanism of recognition can be expressed through different mechanisms such as territorial behaviour, dominance hierarchy, and ritualised aggressive behaviour. Territorial behaviour is the expression of a strong intraspecific aggressiveness, by which workers of a colony defend an area of their vital domain against neighbouring conspecifics. In arboreal ant mosaics, dominance hierarchy can exist between dominant ants, and should explain the overturning of dominant ants in time. Ritualised behaviours were observed under intra- and interspecific low-aggressiveness conditions and allow to economise the loss of one or several workers during fights whose issue are uncertain. Their systematic study would greatly facilitate understanding of the evolution of arboreal mosaics.  相似文献   

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The excavation of the mass grave from the Monastery of the Observance dating from the Great Plague of Marseilles revealed the first evidence of an autopsy on the skullofa 15-year-old boy, performed during the spring of 1722. The reconstruction of the skull allows us to reconstitute the anatomic technique used, which is identical to those described in a surgical book dating from 1708. This research highlights the interest in correlating the biological and historical archives, and brings new anthropological data to the debate on the contagious nature of the plague.  相似文献   

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Limbedemas of lymphatic origin, either primary, or secondary, represent a chronic disease sometimes heavy to bear by patients who suffer from them. These lymphedemas imply specific care by physical therapists trained to the use of different therapeutic approaches. Until a few years, only the treatments of secondary lymphedemas after radiotherapy and/or complete nodal dissection for cancer were reimbursed by the national health insurance system in Belgium. The introduction of the primary congenital lymphedemas as a disease also reimbursed raised several problems and led to a redefinition of these situations and of their cares. The definition and classification of the lymphedemas in view of the reimbursement of their treatments by the national health insurance system are now officially based (not only on the sole clinical history but) mainly on their clinical severity and/or also on the result of their lymphoscintigraphic investigation (according to a methodological protocol and to diagnostic criteria adopted at the national level). The reimbursements of the treatments by the physical therapists were also adapted and improved. The lymphocintigraphic investigations of the limbedemas became so essential in the management of the lymphedematous situations and in the reimbursement of their physical treatments in Belgium.  相似文献   

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Summary Acid phosphatase activity detected by the Gomori method applied to E.M. appears electively in all the golgian dictyosomes and in the young lysosomes. In the dictyosomes, this activity is more pronounced than it has been shown hitherto and may be detected in the whole bulk of the cisternae. Nevertheless the activity is greater in the lateral and distal parts of the system. A morphological analysis of numerous dictyosomes, both on normal and on cytochemical preparations, allows to establish a representation of the flow of the enzyme through two directions: proximo-distal and medio-lateral.Résumé L'activité phosphatasique acide, mise en évidence par la réaction de Gomori apparait de façon élective dans tous les dictyosomes golgiens ainsi que dans les lysosomes jeunes. Dans les dictyosomes, l'activité est considérable au point qu'elle peut être décelée dans l'ensemble des citernes. Néanmoins, elle est prépondérante dans les parties latérales et distale du système. Une analyse morphologique de nombreux dictyosomes, faite conjointement sur coupes normales et sur coupes histochimiques permet d'établir un schéma du flux de l'enzyme suivant deux vecteurs: proximo-distal et médio-latéral.  相似文献   

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Objective

To assess the efficacy and safety of percutaneous testicular biopsy to provide sperm cells for ICSI in male patients with azoospermia not amenable to surgical treatment.

Materials and methods

From October 1995 to December 2001, 175 biopsies were performed in men with azoospermia to provide material for intracytoplasmic sperm injection. Azoospermia was obstructive (OA) in 41 cases and non-obstructive (NOA) in 134 cases. Open biopsy was performed in the first 15 patients in the series and percutaneous biopsy was performed on an outpatient basis, under local anesthesia, with a Biopty Gun® (14G needle), in the subsequent patients as the first step in management. Open surgical biopsies were performed in another 15 patients following a sperm cell-negative percutaneous biopsy.

Results

All biopsies performed for OA were positive, but only 51/134 biopsies (38%) were positive in the NOA group. The material provided by percutaneous biopsy, when positive for sperm cells, was always sufficient to perform ICSI. When percutaneous biopsy was negative, open surgical biopsy failed to give better results. Five men developed minor complications (acute hematocele) following percutaneous biopsies requiring reoperation for hemostasis (3.12%). No major complications were observed. Results were comparable in terms of fertilization and pregnancy rates whether fresh or frozen-thawed sperm was used.

Conclusion

Percutaneous testicular sperm extraction is a safe, well-tolerated and cost-effective procedure in the management of male-factor infertility related to azoospermia.  相似文献   

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