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31.
Four new dinoflagellates 总被引:1,自引:0,他引:1
Enrique Balech 《Helgoland Marine Research》1990,44(3-4):387-396
Fragilidium fissile is a new species of this rare genus. It somewhat resemblesF. subglobosum. It differs from the latter in having a slot and a pore in the first apical plate 1′ (the nomenclature of dinoflagellate
plate designation follows the Kofoid system). Both species are also distinguishable by noticeable differences in Po, 1″″ and
1‴.Peridinium tyrrhenicum is a small species differing from all the other known species ofPeridinium in its shape, apical channel and several plates, especially some of the sulcal components.Alexandrium foedum somewhat resemblesA. balechii, but it differs from the latter in that its width is greater than its length, and in the characters of all the main sulcal
plates. The above listed species were found in a sample from the Tyrrhenian Sea. The fourth species,Alexandrium andersoni, is a small dinoflagellate obtained in coastal waters off Cape Cod. It differs from all the other species of the minutum
group in the very typical shapes of both the 6″ and the S. s.Pentapharsodinium daleii Indelicato and Loeblich is transferred toPeridinium. 相似文献
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34.
Enrique Galindo Guadalupe Salcedo Ma. Eugenia Ramírez 《Applied microbiology and biotechnology》1994,40(5):634-637
Xanthomonas campestris NRRL B-1459 and a variant E2, when preserved on agar slopes (transferred monthly) over 11 months did not deteriorate in their ability to produce xanthan in quantity and quality, as determined by culture in 500-ml baffled flasks. Variations between 8 and 14% (with respect to the average) in the final xanthan concentration were observed for the E2 and B-1459 strains, respectively. A wide range of final viscosities was obtained; these were consistent with the changes in gum concentration. Differences were more likely associated with differences in fermentation kinetics rather than being inherent to the strains. The rheological quality of both polysacharides was relatively constant throughout the time of culture maintenance. Preservation of these bacteria on agar slopes was an adequate method, in contrast to previous reports. In the period studied, strain E2 produced higher gum titres and slightly lower gum quality compared to strain B-1459.
Correspondence to: E. Galindo 相似文献
35.
Enrique Cerdá-Olmedo Rafael Fernández-Martín Javier Ávalos 《Antonie van Leeuwenhoek》1994,65(3):217-225
Gibberella fujikuroi (Fusarium moniliforme) is a complex group of plant pathogens. Some strains produce gibberellic acid and other gibberellins that promote growth and regulate various stages in plant development.The paper describes the research effort directed to development of genetic tools for this species. Furthermore the main features of the gibberellin biosynthetic pathway as established in Gibberella are described.Abbreviations AMO 1618
2-isopropyl-4-(trimethylammonium chloride)-5-methylphenylpiperidine-1-carboxylate
- hydroxykaurenoic acid
ent-kaur-16-en-7-ol-19-oic acid
- kaurenal
ent-kaur-16-en-19-al
- kaurene
ent-kaur-16-ene
- kaurenoic acid
ent-kaur-16-en-19-oic acid
- kaurenol
ent-kaur-16-en-19-ol
- paclobutrazol
1-(4-chlorophenyl)-4,4-dimethyl-2-(1,2,4-triazol-lyl)pentan-3-ol
- pefurazoate
pent-4-enyl-N-furfuryl-N-imidazol-1-ylcarbonyl-DL-homoa laninate
- tetcyclacis
5-(4-chlorophenyl)-3,4,5,9,10-pentaazatetracyclo-5,4,102.6,O8.11-dodeca-3,9-diene
- triarimol
-(2,4-dichlorophenyl)--phenyl-5-pyrimidine methyl alcohol 相似文献
36.
Miguel Lara-Aparicio Santiago López de Medrano Beatriz Fuentes-Pardo Enrique Moreno-Sáenz 《Bulletin of mathematical biology》1993,55(1):97-110
Based on experimental work on the ontogeny of the electroretinogram circadian rhythm in crayfish, we present a mathematical
model simulating changes in both frequency and amplitude of the electroretinogram oscillation during several developmental
stages until shortly before the adult age. Simultaneously, we propose a hypothetical oscillation in the hormonal release whose
frequency is imposed on the electroretinogram oscillation. The model consists of two coupled nonlinear oscillators in which
a dynamical response is obtained mainly through an Andronov-Hopf bifurcation. Through the construction of the model, a biological
hypothesis about the essential elements underlying the ERG circadian rhythm and their interrelations is formulated and discussed. 相似文献
37.
Alfonso Gozalo Alfonso Chavera Gerald E. Dagle Enrique Montoya Richard E. Weller 《Journal of medical primatology》1993,22(7-8):431-432
A wild-caught adult female Saguinus mystax died after 54 months in captivity. At necropsy, a small reddish zone in the renal cortex of one kidney was shown histologically to be a hemangiosarcoma. 相似文献
38.
The interactions of VO2+ with phytate to form both soluble and insoluble complexes, have been studied by electronic absorption spectroscopy. A soluble
1∶1 VO2+: phytate complex is formed at pH <1. At higher pH-values insoluble complexes are produced. Two different solid complexes,
obtained respectively at pH=2 and 4, were isolated and characterized. The maximal bonding ratio of VO2+: phytate was found to be 4, on the basis of a pH binding profile. 相似文献
39.
Mortimer M. Civan Jonathan Robbins Simon Broad Enrique Rozengurt David A. Brown 《The Journal of membrane biology》1993,133(1):51-59
Summary Differentiated neuroblastoma cells exhibit both the delayed rectifier potassium current (I
K) and the M-current (I
M). The present study was designed to determine the roles of protein kinase C (PKC) and of the calmodulin-binding protein 80K/MARCKS, a prominent substrate for PKC and possible regulator of these currents. Neuroblastoma x glioma (NG108-15) hybrid cells transfected with m1 muscarinic receptors were grown with 1% fetal bovine serum (FBS) without the prostaglandin E1 (PGE1) and isobutylmethylxanthine (IBMX) usually added in preparation for electrophysiological studies. Under these conditions, the usual pleomorphism was largely abolished, leaving two populations of small cells with stellate and spherically symmetrical geometries. Whole-cell patch clamping indicated that the two cell types had identical electrophysiological properties, displaying: I
k, a small current through a T-like Ca2+ channel, and no M-current.Stimulation with carbachol shifted the distribution of cells to a more stellate morphology within 24 hr and later (after 48 hr) reduced the PKC substrate 80K/MARCKS by 22±7%. In contrast to the stimulation of I
k observed with cardiac cells, PKC activation produced only a small inhibition of I
k, which was independent of carbachol pretreatment. Thus, PKC and 80K/MARCKS can be dissociated from the regulation of I
k in neuroblastoma cells.Supported in part by research grants from the National Institutes of Health (DK-40145 and EY-08343) and from the U.K. Medical Research Council.We thank Dr. Peter J. Parker for his generous gift of PKC, and Yvonne Vallis for her skillful assistance with the cultures and harvesting of the NG108-15 transfected cells. 相似文献
40.
Edgar Antonio Rodríguez-Negrete Enrique Alejandro Guevara-Rivera Ángela Paulina Arce-Leal Norma Elena Leyva-López Jesús Méndez-Lozano 《Molecular Plant Pathology》2023,24(10):1300-1311
The nonstructural protein NSm of tomato spotted wilt virus (TSWV) has been identified as the avirulence determinant of the tomato single dominant Sw-5 resistance gene. Although Sw-5 effectiveness has been shown for most TSWV isolates, the emergence of resistance-breaking (RB) isolates has been observed. It is strongly associated with two point mutations (C118Y or T120N) in the NSm viral protein. TSWV-like symptoms were observed in tomato crop cultivars (+Sw-5) in the Baja California peninsula, Mexico, and molecular methods confirmed the presence of TSWV. Sequence analysis of the NSm 118–120 motif and three-dimensional protein modelling exhibited a noncanonical C118F substitution in seven isolates, suggesting that this substitution could emulate the C118Y-related RB phenotype. Furthermore, phylogenetic and molecular analysis of the full-length genome (TSWV-MX) revealed its reassortment-related evolution and confirmed that putative RB-related features are restricted to the NSm protein. Biological and mutational NSm 118 residue assays in tomato (+Sw-5) confirmed the RB nature of TSWV-MX isolate, and the F118 residue plays a critical role in the RB phenotype. The discovery of a novel TSWV-RB Mexican isolate with the presence of C118F substitution highlights a not previously described viral adaptation in the genus Orthotospovirus, and hence, the necessity of further crop monitoring to alert the establishment of novel RB isolates in cultivated tomatoes. 相似文献