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Résumé L'étude d'un précurseur probable dans la production de l'acide nicotinique par leMycobacterium tuberculosis hominis, révéla que les acides aminiques hétérocycliques, qui sont indispensables à plusieurs organismes, comme le tryptophan et l'histidine, sont bactériostatiques à l'organisme. Cet organisme se développait dans une solution synthétique de Proskauer & Beck (Vorwald's modification). Les acides aminiques tels que l'ornithine et l'arginine aidèrent à sa croissance et favorisèrent la production d'acide nicotinique, ressemblant sur ce point à l'asparagine. Des études préliminaires faites sur des cobayes infectés par l'organisme tuberculeux confirmèrent l'effet bactériostatique du tryptophanein vitro. Du tryptophane fut administré, de fa?on sous-cutanée, à raison de 125 mg par jour pour 10 jours consécutifs, immédiatement après l'infection, à un groupe d'animaux. Un second groupe subit le même traitement, mais à deux semaines du jour de l'infection. Un troisième groupe fut infecté, mais laissé sans traitement. Tous ces animaux furent observés pendant 9 semaines. Après examen bactériologique, microscopipue et macroscopique, l'effet bactériostatique du tryptophanein vivo put être démontré.   相似文献   
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Comparative study of the urease in the rumen wall and rumen content   总被引:1,自引:0,他引:1  
S Abdel Rahman 《Nature》1966,209(5023):618-619
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Résumé L'étude des effets de l'indole sur l'organismeM. tuberculosis hominis révéla qu'il est bactériostatiquein vitro etin vivo chez les cobayes infectés par lui (5 mg par jour pendant 15 jours). Les acides indol-acétiques et indolpropioniques sont aussi légèrement tuberculostatiques.  相似文献   
4.
The paper describes two new Dugesia species collected from the rivers Messassi and Ntsetsensooh in Cameroon, representing the first planarian flatworms documented from this country. Based on morphological data, the new species Dugesia bijuga Harrath & Sluys, sp. nov. is characterized mainly by the presence of two diaphragms, a barrel-shaped penis that is traversed by numerous ducts of penis glands and is provided with a short nozzle, and the presence of two atrial folds. The other new species, Dugesia pustulata Harrath & Sluys, sp. nov., is characterized mainly by absence of a penis bulb, presence of a large, elongated and weakly muscular seminal vesicle, and by the ventroposterior section of the bursal canal being thrown into distinct folds. The phylogenetic position of the two new species was determined through a molecular phylogenetic tree, based on a mitochondrial and a nuclear gene, including species from the major geographical range of distribution of the genus Dugesia. The phylogenetic tree revealed that the Cameroon lineage does not constitute a monophyletic group with the other Afrotropical species; it also showed that the African continent may house a great diversity of Dugesia species that still remains to be discovered.

urn:lsid:zoobank.org:pub:007441A5-F037-4950-9F5B-AD6ED12A40ED  相似文献   

5.
We report herein the molecular and morphological characteristics of two myxozoan parasites, Ceratomyxa ghannouchensis n. sp. and Ceratomyxa pallida Thélohan, 1894 infecting the gallbladder of the bogue, Boops boops (Linnaeus, 1758) in the Gulf of Gabès off the Tunisian coast. Mature myxospores of C. ghannouchensis were stubby with a convex anterior end and almost straight to slightly concave posterior one. Mature myxospores measured 5.8 ± 0.4 (5–7) µm in length and 11.7 ± 0.3 (11–13) µm in thickness. Valves were unequal in size with one occasionally tapering to a greater degree than the other. The polar capsules were equal in size, spherical in shape and measured 2 ± 0.2 (1.8–2.8) µm in diameter. Infection with C. pallida occurs as spherical to elongated mono-, di- or trisporic plasmodia floating in the bile. Mature myxospores were crescent-shaped with two symmetrical shell valves with rounded edges. The myxospores measured 6 ± 0.5 (5–7) µm in length and 28.5 ± 2.5 (26–33) µm in thickness. The polar capsules were spherical, equal in size and measured 3 ± 0.3 (2.7–3.3) µm in diameter. Based on the SSU rDNA partial sequence, C. ghannouchensis n. sp. and C. pallida appeared in the same subclade with Ceratomyxa leatherjacketi and Ceratomyxa tunisiensis.

www.zoobank.org/urn:lsid:zoobank.org:pub:0DE35680-A3C9-45BA-B29B-0B7462CA7A43  相似文献   

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The identification of tumor-suppressor genes in solid tumors by classical cancer genetics methods is difficult and slow. We combined nonsense-mediated RNA decay microarrays and array-based comparative genomic hybridization for the genome-wide identification of genes with biallelic inactivation involving nonsense mutations and loss of the wild-type allele. This approach enabled us to identify previously unknown mutations in the receptor tyrosine kinase gene EPHB2. The DU 145 prostate cancer cell line, originating from a brain metastasis, carries a truncating mutation of EPHB2 and a deletion of the remaining allele. Additional frameshift, splice site, missense and nonsense mutations are present in clinical prostate cancer samples. Transfection of DU 145 cells, which lack functional EphB2, with wild-type EPHB2 suppresses clonogenic growth. Taken together with studies indicating that EphB2 may have an essential role in cell migration and maintenance of normal tissue architecture, our findings suggest that mutational inactivation of EPHB2 may be important in the progression and metastasis of prostate cancer.  相似文献   
8.
Résumé La quantité de porphyrins faecaux et sanguins trouvée dans 21 cas de pellagrins normale comparée à celle des cas normaux observés en Egypte. Cependant, dans 5 cas les porphyrins sanguins et faecaux furent plus nombreux et les porphyrins urinaires restèrent en quantité normale.  相似文献   
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This article reports the effect of ageing on the microstructure, martensitic transformation, magnetic properties, and mechanical properties of Ni51Fe18Ga27Ti4 shape memory alloy. There are five specimens of this alloy aged at 573 up to 973 K for 3 h per each. This range of ageing temperature greatly affects the microstructure of the alloy. As the ageing temperature increased from 573 up to 973 K, the microstructure of Ni51Fe18Ga27Ti4 alloy gradually changed from the entirely martensitic matrix at 573 K to the fully austenitic microstructure at 973 K. The volume fraction of precipitated Ni3Ti particles increased with the ageing temperature increasing from 573 to 773 K. Further increasing the ageing temperature to 973 K decreased the content of Ni3Ti in the microstructure. The martensitic transformation temperature was decreased steadily by increasing the ageing temperature. The magnetization saturation, remnant magnetization, and coercivity increased with the ageing temperature increasing up to 773 K. A further increase in ageing temperature decreased these magnetic properties. Moreover, the hardness values were gradually increased at first by increasing the ageing temperature to 773 K, and then dramatically decreased to the lowest value at 973 K.  相似文献   
10.
Large-scale granitic plutons are exposed in the Ergun block in the northern part of the Da Hinggan Range, but their emplacement age and petrogenesis remain unknown. Of these plutons, the Tahe pluton is composed mainly of porphyritic syenogranite and monzogranite, with minor hornblende alkali feldspar granite and gabbro, which have affinities to post-orogenic granitoids. Laser-ablation Inductively Coupled Plasma Mass-spectroscope (LA-ICP-MS) analysis shows that the major rock types of the Tahe pluton formed at 494- 480 Ma ago, indicating its emplacement in the Early Paleozoic. It is concluded, therefore, that the collision between the Ergun and the Xing'an blocks ended in Early Paleozoic. Considering the geochronological data of the plutons in the adjacent areas, the Early Paleozoic evolutionary history of the Ergun block is similar to the central Mongolia and the Tuvino blocks in Mongolia, and the Ergun block should be a part of the accretionary continental margin in the southern Siberian Craton.  相似文献   
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