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201.
Jean-Jacques Tiercelin 《Geobios》1977,10(3):489-492
In the Durance valley below Sisteron, the clay minerals of the material forming the fluvio-glacial pleistocene terraces and the superposed paleosols concur to correlate these levels with the glacial complex of the Laragne-Sisteron basin. 相似文献
202.
Asterogyne guianensis, a new species from French Guiana, is described and illustrated. The differences between this and the morphologically similarA. spicata are given. A map and discussion of distribution is given for all five species of the genus.
Studies on the Flora of the Guianas number 28. 相似文献
203.
Z.William Wolkowski Dominique Moccatti Françoise Heymans Jean-Jacques Godfroid 《Journal of theoretical biology》1977,66(1):181-193
A multiparameter regression analysis utilizing physico-chemical parameters, and commonly known as the Hansch approach has been extended to a set of existing data on olfactive threshold and olfactive stimulatory effectiveness of organic molecules.The compatibility of various parameters has been studied with adequate statistical methods, and we conclude that the lipophilic character (expressed by the octanol/water partition coefficient) of the molecules is an essential parameter related to preliminary non-specific action and transport across the muceous/lipid interphase and the membrane of the olfactive organ.Such an approach allows the refocusing of the problem of the relationship between structure and olfactive properties. 相似文献
204.
205.
Mandja Bien-Aimé Handschumacher Pascal Bompangue Didier Gonzalez Jean-Paul Muyembe Jean-Jacques Sauleau Erik-André Mauny Frédéric 《EcoHealth》2022,19(3):354-364
EcoHealth - Monkeypox (MPX) is an emergent severe zoonotic disease resembling that of smallpox. To date, most cases of human MPX have been reported in the Democratic Republic of the Congo (DRC).... 相似文献
206.
The Myriapoda and Onychophora collection dataset inventories the occurrence records of the collection of myriapods and onychophorans in the Muséum national d’Histoire naturelle, Paris. The dataset currently consists of 202 lots of onychophorans, representing all of those present, and almost ten thousand (9 795) lots of myriapods, representing 33 to 40% of the MNHN Myriapoda collection. This collection, which is of key historic importance, represents the results of two centuries of myriapod and onychophoran studies. The sources of the collection are worldwide, with a high representation for metropolitan France for the myriapods. None of the occurrences are yet georeferenced. Access to the dataset via the data portals of the MNHN and the GBIF has been made possible through the e-ReColNat project (ANR-11-INBS-0004).The Myriapoda and Onychophora collection of MNHN is actively expanding, hence both the collection and dataset are in continuous growth. The dataset can be accessed through the portals of GBIF at http://www.gbif.org/dataset/3287044c-8c48-4ad6-81d4-4908071bc8db and the MNHN at http://science.mnhn.fr/institution/mnhn/collection/my/item/search/form. 相似文献
207.
Delouvrié B Al-Kadhimi K Arnould JC Barry ST Cross DA Didelot M Gavine PR Germain H Harris CS Hughes AM Jude DA Kendrew J Lambert-van der Brempt C Lohmann JJ Ménard M Mortlock AA Pass M Rooney C Vautier M Vincent JL Warin N 《Bioorganic & medicinal chemistry letters》2012,22(12):4117-4121
Potent antagonists of the integrin α(5)β(1), which are RGD mimetics built from tyrosine are described. This paper describes the optimization of in vitro potency obtained by variation of two parts of the molecule, the central aromatic core and the amide moiety. 相似文献
208.
Johnson AA Sayer JM Yagi H Patil SS Debart F Maier MA Corey DR Vasseur JJ Burke TR Marquez VE Jerina DM Pommier Y 《The Journal of biological chemistry》2006,281(43):32428-32438
Integration of the viral cDNA into host chromosomes is required for viral replication. Human immunodeficiency virus integrase catalyzes two sequential reactions, 3'-processing (3'-P) and strand transfer (ST). The first integrase inhibitors are undergoing clinical trial, but interactions of inhibitors with integrase and DNA are not well understood in the absence of a co-crystal structure. To increase our understanding of integrase interactions with DNA, we examined integrase catalysis with oligonucleotides containing DNA backbone, base, and groove modifications placed at unique positions surrounding the 3'-processing site. 3'-Processing was blocked with substrates containing constrained sugars and alpha-anomeric residues, suggesting that integrase requires flexibility of the phosphodiester backbone at the 3'-P site. Of several benzo[a]pyrene 7,8-diol 9,10-epoxide (BaP DE) adducts tested, only the adduct in the minor groove at the 3'-P site inhibited 3'-P, suggesting the importance of the minor groove contacts for 3'-P. ST occurred in the presence of bulky BaP DE DNA adducts attached to the end of the viral DNA suggesting opening of the active site for ST. Position-specific effects of these BaP DE DNA adducts were found for inhibition of integrase by diketo acids. Together, these results demonstrate the importance of DNA structure and specific contacts with the viral DNA processing site for inhibition by integrase inhibitors. 相似文献
209.
Bone marrow mesenchymal stem cells suppress lymphocyte proliferation in vitro but fail to prevent graft-versus-host disease in mice 总被引:18,自引:0,他引:18
Sudres M Norol F Trenado A Grégoire S Charlotte F Levacher B Lataillade JJ Bourin P Holy X Vernant JP Klatzmann D Cohen JL 《Journal of immunology (Baltimore, Md. : 1950)》2006,176(12):7761-7767
Several reports have suggested that mesenchymal stem cells (MSCs) could exert a potent immunosuppressive effect in vitro, and thus may have a therapeutic potential for T cell-dependent pathologies. We aimed to establish whether MSCs could be used to control graft-vs-host disease (GVHD), a major cause of morbidity and mortality after allogeneic hemopoietic stem cell transplantation. From C57BL/6 and BALB/c mouse bone marrow cells, we purified and expanded MSCs characterized by the lack of expression of CD45 and CD11b molecules, their typical spindle-shaped morphology, together with their ability to differentiate into osteogenic, chondrogenic, and adipogenic cells. These MSCs suppressed alloantigen-induced T cell proliferation in vitro in a dose-dependent manner, independently of their MHC haplotype. However, when MSCs were added to a bone marrow transplant at a MSCs:T cells ratio that provided a strong inhibition of the allogeneic responses in vitro, they yielded no clinical benefit on the incidence or severity of GVHD. The absence of clinical effect was not due to MSC rejection because they still could be detected in grafted animals, but rather to an absence of suppressive effect on donor T cell division in vivo. Thus, in these murine models, experimental data do not support a significant immunosuppressive effect of MSCs in vivo for the treatment of GVHD. 相似文献
210.
Dynamics of a Pig Slurry Microbial Community during Anaerobic Storage and Management 总被引:6,自引:3,他引:3 下载免费PDF全文
Pascal Peu Hubert Brugre Anne-Marie Pourcher Monique Krourdan Jean-Jacques Godon Jean-Philippe Delgens Patrick Dabert 《Applied microbiology》2006,72(5):3578-3585
The microbial community of a pig slurry on a farm was monitored for 6 months using both molecular and cultural approaches. Sampling was carried out at all the different stages of effluent handling, from the rearing build-up to slurry spreading. Total DNA of each sample was extracted and analyzed by PCR-single-strand conformation polymorphism (SSCP) analysis using primers targeting the 16S rRNA genes from the archaeal and bacterial domains and also the Eubacterium-Clostridium, Bacillus-Streptococcus-Lactobacillus, and Bacteroides-Prevotella groups. A comparison of the SSCP profiles showed that there were rapid changes in the dominant bacterial community during the first 2 weeks of anaerobic storage and that the community was relatively stable thereafter. Several bacterial populations, identified as populations closely related to uncultured Clostridium and Porphyromonas and to Lactobacillus and Streptococcus cultured species commonly isolated from pig feces, remained present and dominant from the rearing build-up to the time of spreading. Enumeration of fecal indicators (enterococci and Escherichia coli) performed in parallel using cultural methods revealed the same trends. On the other hand, the archaeal community adapted slowly during pig slurry storage, and its diversity increased. A shift between two hydrogenotrophic methanogenic Methanobrevibacter populations from the storage pit to the pond was observed. Microorganisms present in pig slurry at the time of spreading could not be detected in soil after spreading by either molecular or cultural techniques, probably because of the detection limit inherent in the two techniques. 相似文献