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71.
Summary The influence of catecholamines on the platelet count was studied in an in vivo experimental model obtained with cannulation of the carotid and of the femoral vein. The i.v. infusion of epinephrine and l-norepinephrine induces a low drop in the platelet count and also potentiate aggregation by ADP. 相似文献
72.
Zusammenfassung Mannich-Basen von 5-Androstan-3-one wurden unter thermodynamisch und kinetisch kontrollierten Bedingungen bromiert. Die Konformation der unter diesen Bedingungen erhaltenen Produkte wurde stark durch die sterischen und polaren Eigenschaften des Substituenten in 2-Stellung beeinflusst. 相似文献
73.
Maria A. Marcialis P. La Colla B. Loddo 《Cellular and molecular life sciences : CMLS》1972,28(9):1117-1118
Riassunto Contrariamente ad altri inibitori specifici dei poliovirus che prevengono RNA-sintesi virale ed effetto citopatologico, ma non hano effetto sui danni precoci che l'infezione induce nel metabolismo cellulare, un derivato tiopirimidinico è anche capace di impedire il blocco precocem virus indotto, delle proteino-sinsteis cellulari.
This work has been supported by the Consigiio Nazionale delle Ricerche, Rome (Italy). 相似文献
This work has been supported by the Consigiio Nazionale delle Ricerche, Rome (Italy). 相似文献
74.
75.
L. Panizzi Maria Luisa Scarpati Giovanna Oriente 《Cellular and molecular life sciences : CMLS》1955,11(10):383-384
Summary Quinic acid methyl ester, having the 1.4 and 5 hydroxy-groups suitably blocked, was condensed with the carbonilcaffeic acid chloride.Gradual hydrolysis of the condensation compound gave place to chlorogenic acid. 相似文献
76.
Maria Assunta Mor 《Cellular and molecular life sciences : CMLS》1956,12(6):224-226
Riassunto L'Autore ha studiato l'influenza della concentrazione degli ioni Ca++ e Mg++ sull'ATPasi degli atri e dei ventricoli di cuore di cavia. Tale attività è maggiore a pH 9,2 che a pH 6,8. Mentre il Ca++ influisce differenziando decisamente le attività degli atri da quelle dei ventricoli, il Mg++ accentua piuttosto una differenza tra la parte destra e la sinistra. Il calore distrugge quasi completamente l'attività enzimatica dopo una permanenza a 60° per 20 min. 相似文献
77.
Hillier LW Graves TA Fulton RS Fulton LA Pepin KH Minx P Wagner-McPherson C Layman D Wylie K Sekhon M Becker MC Fewell GA Delehaunty KD Miner TL Nash WE Kremitzki C Oddy L Du H Sun H Bradshaw-Cordum H Ali J Carter J Cordes M Harris A Isak A van Brunt A Nguyen C Du F Courtney L Kalicki J Ozersky P Abbott S Armstrong J Belter EA Caruso L Cedroni M Cotton M Davidson T Desai A Elliott G Erb T Fronick C Gaige T Haakenson W Haglund K Holmes A Harkins R Kim K Kruchowski SS Strong CM Grewal N Goyea E 《Nature》2005,434(7034):724-731
Human chromosome 2 is unique to the human lineage in being the product of a head-to-head fusion of two intermediate-sized ancestral chromosomes. Chromosome 4 has received attention primarily related to the search for the Huntington's disease gene, but also for genes associated with Wolf-Hirschhorn syndrome, polycystic kidney disease and a form of muscular dystrophy. Here we present approximately 237 million base pairs of sequence for chromosome 2, and 186 million base pairs for chromosome 4, representing more than 99.6% of their euchromatic sequences. Our initial analyses have identified 1,346 protein-coding genes and 1,239 pseudogenes on chromosome 2, and 796 protein-coding genes and 778 pseudogenes on chromosome 4. Extensive analyses confirm the underlying construction of the sequence, and expand our understanding of the structure and evolution of mammalian chromosomes, including gene deserts, segmental duplications and highly variant regions. 相似文献
78.
The faithful inheritance of genetic information, which is essential for all organisms, requires accurate DNA partition (segregation) at cell division. In prokaryotes, partition is mediated by par systems, for which the P1 plasmid system of Escherichia coli is a prototype comprising a partition site and two proteins, ParA and ParB. To form the partition complex necessary for segregation, P1 ParB must recognize a complicated arrangement of A-box and B-box DNA motifs located on opposite ends of a sharply bent parS partition site of approximately 74 bp (refs 3-7). Here we describe structures of ParB bound to partition sites. ParB forms an asymmetric dimer with extended amino-terminal HTH (helix-turn-helix) domains that contact A-boxes. The two HTH domains emanate from a dimerized DNA-binding module composed of a six-stranded beta-sheet coiled-coil that binds B-boxes. Strikingly, these individual DNA-binding modules rotate freely about a flexible linker, enabling them to contact several arrangements of A- and B-boxes. Most notably, each DNA-binding element binds to and thus bridges adjacent DNA duplexes. These unique structural features of ParB explain how this protein can bind complex arrays of A- and B-box elements on adjacent DNA arms of the looped partition site. 相似文献
79.
A. Pessina Maria Grazia Neri A. Muschiato 《Cellular and molecular life sciences : CMLS》1982,38(9):1056-1057
Summary Filtrates fromE. coli H10407 cultures, giving a positive response for heat-labile enterotoxin (LT) in the Y-1 cell test, show an inhibitory activity both on3H-thymidine uptake by Ehrlich ascites cells and on granulocytic-macrophagic precursors (CFU-C) in murine bone marrow.Acknowledgments. We gratefully acknowledge the expert technical assistance of L. Basso and A. Gerosa of Department of Pathology, Hospital of Desio. 相似文献
80.
L. Mazzanti M. Lopez Maria Grazia Berti 《Cellular and molecular life sciences : CMLS》1964,20(9):492-493
Riassunto Gli autori descrivono le lesioni del testicolo del ratto osservate nel corso di sperimentazioni con la fluoroacetamide. Tali lesioni consistono in alterazioni regressive interessanti elettivamente la linea seminale. 相似文献