Showing papers by "Institut national de la recherche agronomique published in 1969"
TL;DR: It is proposed that certain repeating regions of immunoglobulin polypeptide chains might have been selected for participation in biological effector functions such as complement fixation (domain hypothesis), and it should be possible to associate a complement fixation function with a specific submolecular domain in certain immunoglOBulin molecules.
Abstract: INDIVIDUAL immunoglobulin molecules often possess several biological activities in addition to reactivity with appropriate antigen. Such activities include complement fixation, skin sensitization, attachment to macrophages and the tissue fixation required for placental passage1,2. Some members of this protein group lack one or more of these capacities: human IgG γ4 myeloma molecules and human IgD are unable to fix complement, for example3,4. Hill et al.5 suggested, on the basis of their observation of repeating amino-acid sequences in immunoglobulins, that these molecules might have arisen by a series of gene duplications, and Edelman et a1.6 have recently proposed that certain repeating regions of immunoglobulin polypeptide chains might have been selected for participation in biological effector functions such as complement fixation (domain hypothesis). According to this concept it should be possible to associate a complement fixation function with a specific submolecular domain in certain immunoglobulin molecules.
120 citations
TL;DR: Findings on pseudo-pregnant rabbits further support the hypothesis of a distinct functional role of the two types of ribosomes, with the selective action of prolactin on the number of bound polyribosomes.
37 citations
TL;DR: In this article, experiments were conducted to determine whether the neuroendocrine reflex is able to modify the parameters which characterize the flow rate of the milk under normal milking conditions, such as intravenous administration of oxytocin, during general anaesthesia, and after unilateral or bilateral denervation of the mammary gland.
Abstract: In order to obtain more information on the importance of the milk ejection reflex in the lactation of normal ewes, experiments were conducted to determine whether the neuroendocrine reflex is able to modify the parameters which characterize the flow rate of the milk under normal milking conditions.Ewes were allowed to suckle their lambs freely during the 3 days following parturition. They were then milked with a machine and the individual milk production was measured volumetrically at each milking. Different fractions obtained during milking (‘machine milk’, ‘machine strippings’ and ‘hand strippings’), and the milk flow, were measured using a sensitive recording system. In further experiments, machine milking was performed after intravenous administration of oxytocin, during general anaesthesia, and after unilateral or bilateral denervation of the mammary gland.The ewes fell into 2 categories: those giving most of their milk in 1 rapid emission, and those giving it in 2 quite separate emissions. The results indicated that the second emission found in some of the ewes was the milk emptied from the acini by the neuroendocrine ejection reflex. Disappearance of the second emission resulted from the administration of oxytocin before milking—which induces passage of the milk from the acini into the mammary cistern—and also from general anaesthesia or denervation of the mammary gland.
31 citations
TL;DR: The induction of milk secretion during normal gestation or after a prolactin injection produces ultrastructural modifications in the mammary gland cell which are characterized by progressive development of the ergastoplasmic membrane system.
Abstract: L'evolution de l'ultrastructure de la cellule epitheliale mammaire de la Lapine est decrite au cours de:
28 citations
TL;DR: Geromyia gen.n. is erected to accommodate the millet grain midge, Itonida penniseti Felt, 1920, a species that attacks developing grain of bulrush millet, Pennisetum typhoides and other species of Pennismetum as discussed by the authors.
Abstract: Geromyia gen.n. is erected to accommodate the millet grain midge, Itonida penniseti Felt, 1920, a species that attacks developing grain of bulrush millet, Pennisetum typhoides and other species of Pennisetum. Cecidomyia penniseti Felt, 1920, Itonida seminis Felt, 1921 and Cecidomyia pennisetoides Barnes, 1956 are synonymised under G. penniseti. The male, female and larva are described and illustrated in detail and the life-cycle and seasonal biology are described from field observations at Bambey, Senegal. G. penniseti is recorded from P. typhoides in India, the Sudan, Nigeria, Senegal, Niger and Upper Volta and is provisionally recognised in collections from P. polystachyon and P. pedicellatum in Ghana, Uganda, Madagascar and Nigeria.
19 citations
01 Jan 1969
TL;DR: Une couronne complexe de gros bourgeons a evolution rapide se differencie enfin pres du point ou la feuille externe, tres engainante, s'insere sur l'axe pour la multiplication vegetative.
Abstract: ResumeLa multiplication vegetative des Cattleya est basee sur la culture in vitro de bourgeons axillaires entiers (5 a 8 mm) preleves sur de jeunes tiges. Les points vegetatifs de l'expiant ne se developpent pas. Au contact de la blessure, on note des dedifferenciations cellulaires et la formation de quelques ilots meristematiques qui ne deviendront pas organogenes. Plus tard, des protuberances de dimensions tres diverses et de nombreuses proliferations foliacees ou en forme de poils recouvrent la base abaxiale des deux feuilles les plus externes, les plus proches de la base.Des massifs de meristeme primaire apparaissent ensuite soit entre les proliferations foliacees, soit au sommet des protocormes. Ils engendrent de petits bourgeons a evolution lente. Une couronne complexe de gros bourgeons a evolution rapide se differencie enfin pres du point ou la feuille externe, tres engainante, s'insere sur l'axe. Leur importance est fondamentale pour la multiplication vegetative. Les deux feuilles les plus externe...
10 citations
TL;DR: In this article, a flow cell photometer is described with automatic cleaning of the photometric cell, denasimetric separation of air bubbles and precipitates, and a constant sensitivity from 0 to 10 mg/ml of bacterial dry weight.
Abstract: A flow cell photometer is described with automatic cleaning of the photometric cell, denasimetric separation of air bubbles and precipitates, and a constant sensitivity from 0 to 10 mg/ml of bacterial dry weight.
9 citations
TL;DR: A mutual stimulative effect of these diseases is obvious from the morbidity and mortality rates as also from the development time of each disease, which shows the importance of the physiological state of the insect to the success of the pathogen.
Abstract: Les effets sur les vers blancs de l'infection successive par la maladie laiteuse aBacillus popilliae «Melolontha» puis par la mycose aBeauveria tenella ont ete etudies en elevage, a 20°C, chez des larves du troisieme stade. Un effet stimulateur reciproque des deux affections a ete mis en evidence d'apres les taux de morbidite et de mortalite ainsi que d'apres les delais d'evolution de chaque maladie. Ce synergisme met en relief l'importance de l'etat physiologique de l'insecte dans le succes de l'intervention d'un pathogene.
5 citations
TL;DR: In this article, a granulose, maladie nouvelle pourMamestra oleracea L., est decrite, and the agent pathogene se multiplie dans la region nucleaire des cellules adipeuses, hypodermiques, and tracheales.
Abstract: Une granulose, maladie nouvelle pourMamestra oleracea L., est decrite. L'agent pathogene se multiplie dans la region nucleaire des cellules adipeuses, hypodermiques et tracheales. Les granules et les virus ont ete observes au microscope electronique. L'elevage d'un nombre de generations successives relativement eleve, rendu possible par l'emploi d'un aliment artificiel, est envisage comme cause d'apparition de maladies a virus.
4 citations