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81.
Cinnamoyl CoA reductase, the first committed enzyme of the lignin branch biosynthetic pathway: cloning, expression and phylogenetic relationships 总被引:15,自引:3,他引:12
82.
83.
Emmanuel Martin Valère Cacheux Hélène Cavé Jean Michel Lapierre Denis Le Paslier Bernard Grandchamp 《Human genetics》1995,96(6):668-670
CDKN4/p27Kip1 is a cyclin-dependent kinase (Cdk) inhibitor implicated in G1 phase arrest, which negatively regulates G1 phase progression in response to TGF, and might represent a tumor suppressor gene. We report here the chromosomal assignment of the human CDKN4 gene to chromosome 12p12.3 in close proximity to highly polymorphic microsatellite markers. 相似文献
84.
Abstract A new H2 CO2-utilizing acetogenic bacterium was isolated from the rumen of a mature deer. This is the first report of a spore-forming Gram-negative bacterial species from the rumen. The organism was a strictly anaerobic, motile rod and was able to grow autotrophically on hydrogen and carbon dioxide. Acetate was the major product detected. Glucose, fructose and lactate were also fermented heterotrophically. The optimum pH for growth was 7.0–7.5, and the optimum temperature was 37–42 °C. Yeast extract was required for growth and rumen fluid was highly stimulatory. The DNA base ratio was 52.9 ± 0.5 mol% G + C. On the basis of these characteristics and fermentation products, the isolate was considered to be different from acetogenic bacteria described previously. 相似文献
85.
Naveen Pathak Rodolfo Salas-Auvert Gaël Ruche Marie-hlne Janna David McCarthy Roger G. Harrison 《Proteins》1995,22(2):182-186
Multiple linear regression was used to quantify the dependence of the antimicrobial activity of 13 peptides upon three calculated or experimentally determined parameters: mean hydrophobicity, mean hydrophobic moment, and α-helix content. Mean hydrophobic moment is a measure of the amphiphilicity of peptides in an α-helical conformation. Antimicrobial activity was quantified as the reciprocal of the measured minimal inhibitory concentration (MIC) against Escherichia coli. One of the peptides was magainin 2, and the remainder were novel peptides designed for this study. The multiple linear regression results revealed that the amphiphilicity of the peptides was the most important factor governing anti-microbial activity compared to mean hydrophobicity orα-helix content. A better regression cf the data was obtained using In(1/MIC + constant) as the dependent variable than with either 1/MIC or In(1/MIC). These results should be useful in designing peptides with higher antimicrobial activity. © 1995 Wiley-Liss, Inc. 相似文献
86.
Autonomous division of the endosperm was induced by in vitro culture of unpollinated ovaries or placenta-attached ovules in Helleborus niger, Lupinus luteus and Melandrium album. The induction frequencies for the three species were 50%, 10–20% and 0.1%, respectively. The endosperms contained up to 20 free nuclei; only a few ovules with 80–420 endosperm nuclei were found. Induction of autonomous division of the endosperm, which is unusual in amphimictic plants, was observed in three new species. No embryos appeared in the ovules. This suggests a developmental independence of the endosperm from the embryo in the culture of unpollinated ovaries or ovules. 相似文献
87.
Enzyme-histochemical methods were used to analyse the activities of alkaline phosphatase (AP), dipeptidylpeptidase IV (DPP IV) and adenosine triphosphatase (ATPase) in capillaries of four different human oro-facial muscles, the major and minor zygomatic, the orbicularis oris and buccinator, one masticatory, the masseter and two limb muscles, the biceps brachii and first dorsal interosseus muscles. In all muscles, except for the orbicularis oris, the majority of the capillaries lacked enzyme activity. Therefore, none of these enzymes seems to be reliable as a general marker for human muscle capillaries. In general, the capillaries of the limb muscles and the major and minor zygomatic and the buccinator, were similar in their staining pattern for AP and ATPase, but differed in DPP IV staining. The orbicularis oris muscle differed from the other muscles by showing the largest proportion of capillaries with AP and ATPase activity. The masseter muscle had the largest proportion of capillaries stained for DPP IV. The muscle specific differences in enzyme activity of the capillaries are in agreement with our previous findings of specific differences between limb, oro-facial and masticatory muscles with respect to capillary supply and composition of fibre types and myosins. The results reflect functional specialization of the capillary bed of human muscles. 相似文献
88.
Summary The immobilization of T. reesei mycelium on activated polymeric sorbent was investigated with respect to the intended flow-trough cellulase production. The retention of extracellular production of cellulolytic enzymes was monitored in a packed-column recycle reactor. Some factors affecting cellulase elution pattern are described. 相似文献
89.
Fetal blood flow was examined during epidural analgesia in six women with uncomplicated pregnancies undergoing elective caesarean section. A non-invasive, ultrasonic technique was used to measure blood flow in the fetal descending aorta and intra-abdominal part of the umbilical vein before induction of analgesia with etidocaine and bupivacaine and 15 and 30 minutes afterwards. No appreciable change in fetal blood flow was observed. 相似文献
90.
Résumé Une candidose intestinale associée à une tumeur épithéliale, à métaplasie glandulaire, à pouvoir invasif marqué, provoquant une gêne du transit, a été découverte chez un Babouin de Guinée,Papio papio (Desm.) de la collection du Parc zoologique de Paris. A cette occasion nous avons rapporté les résultats concernant deux autres affections du tube digestid de nos Babouins captifs.
Report of a case of candidiasis of the digestive tract associated to an obstructive epithelial tumor, with great invasive ability, in a captive Baboon,Papio papio (Desm.). Included is a discussion of the incidence of some intestinal disturbances involving candidiasis of subhuman Primates.相似文献