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531.
532.
Paul D. Pratt John C. Herr Raymond I. Carruthers Guillermo Cabrera Walsh 《Biocontrol Science and Technology》2019,29(4):405-409
The leaf-mining fly Hydrellia egeriae Rodrigues-Junior (Diptera: Ephydridae) was evaluated under quarantine conditions as a candidate biological control agent of the invasive aquatic weed Egeria densa Planchon (Hydrocharitaceae) in California, U.S.A. The objective of this study was to test the fly’s feeding preference for E. densa as compared to the North American native Elodea canadensis Michaux (Hydrocharitaceae), an important benchmark species. No choice testing revealed that H. egeriae can complete development on E. canadensis and choice testing indicated the fly presents little oviposition discrimination between E. densa and E. canadensis. It is concluded that the host range of H. egeriae is too broad for use as a biological control agent of E. densa in the U.S.A. 相似文献
533.
Soren Naaby-Hansen Alan Diekman Jagathpala Shetty Charles J Flickinger Anne Westbrook John C Herr 《Reproductive biology and endocrinology : RB&E》2010,8(1):6
Background
The precise composition of the human sperm plasma membrane, the molecular interactions that define domain specific functions, and the regulation of membrane associated proteins during the capacitation process, still remain to be fully understood. Here, we investigated the repertoire of calcium-regulated proteins associated with the human sperm plasma membrane. 相似文献534.
Ethanol-induced acute esophageal motor dysfunction 总被引:7,自引:0,他引:7
535.
Alberto Ruiz Marta Herráez Stefanie B. Costa-Gutierrez María Antonia Molina-Henares María Jesús Martínez Manuel Espinosa-Urgel Jorge Barriuso 《Environmental microbiology》2021,23(5):2433-2447
Interkingdom communication is of particular relevance in polymicrobial biofilms. In this work, the ability of the fungus Ophiostoma piceae to form biofilms individually and in consortium with the bacterium Pseudomonas putida, as well as the effect of fungal and bacterial signal molecules on the architecture of the biofilms was evaluated. Pseudomonas putida KT2440 is able to form biofilms through the secretion of exopolysaccharides and two large extracellular adhesion proteins, LapA and LapF. It has two intercellular signalling systems, one mediated by dodecanoic acid and an orphan LuxR receptor that could participate in the response to AHL-type quorum sensing molecules (QSMs). Furthermore, the dimorphic fungus O. piceae uses farnesol as QSM to control its yeast to hyphae morphological transition. Results show for the first time the ability of this fungus to form biofilms alone and in mixed cultures with the bacterium. Biofilms were induced by bacterial and fungal QSMs. The essential role of LapA-LapF proteins in the architecture of biofilms was corroborated, LapA was induced by farnesol and dodecanol, while LapF by 3-oxo-C6-HSL and 3-oxo-C12-HSL. Our results indicate that fungal signals can induce a transient rise in the levels of the secondary messenger c-di-GMP, which control biofilm formation and architecture. 相似文献
536.
537.
M. J. Salinas A. T. Romero G. Blanca R. de la Herrán M. Garrido-Ramos C. Ruíz-Rejón C. Morales M. Ruíz-Rejón V. Suárez 《Plant Systematics and Evolution》2003,237(3-4):153-164
To solve problems concerning the status of the taxa described in the genus Sarcocapnos, we have conducted a study using morphological, pollen morphology (light microscopy), cytogenetic and molecular techniques.
Focusing on the last technique, we have sequenced ITS-1 and ITS-2 of nuclear rDNA. The species differ basically according
to 5 morphological traits (leaf shape, flower spur, corolla colour, corolla size, and crest of the stigmatic surface). The
cytogenetic analyses indicated n=16 to be the standard chromosome number. The ITS analyses showed that the genus is monophyletic,
defining two main well-supported clades, one containing S. saetabensis and S. enneaphylla, and one containing the rest of the species. In this second clade, S. speciosa, S. pulcherrima, and S. baetica subsp. ardalii are related, as are S. integrifolia, S. crassifolia subsp. crassifolia, and S. crassifolia subsp. atlantis; S. baetica subsp. baetica forms a trichotomy with the foregoing groups. S. speciosa is shown to be a species separate from S. crassifolia subsp. crassifolia, as in the case of S. baetica with respect to S. integrifolia. Palynologically, the parameters used enabled us to establish clear differences between the taxa, often corroborating the
macromorphological and genetic data. The flower spur has been reduced several times in different groups of the genus, for
which the classifications established on the basis of this trait are paraphyletic.
Received July 16, 2002; accepted December 11, 2002 Published online: March 31, 2003 相似文献
538.
N. Sainz Herrán J. L. Casas López J. A. Sánchez Pérez Y. Chisti 《World journal of microbiology & biotechnology》2010,26(8):1409-1418
Effects of ultrasound amplitude and duty cycle on cultures of Aspergillus terreus are reported in a 25 l slurry bubble column sonobioreactor. Fermentations were carried out batchwise. A 2k-factorial design with added central points was used. Sonication at any cycle and amplitude level did not affect biomass growth
rate and yield relative to nonsonicated control, but did affect growth morphology. Ultrasound disrupted fungal pellets and
caused the biomass to grow mainly as dispersed hyphae. Production of lovastatin was reduced by medium- and high-cycle sonication.
Sonication affected broth rheology. In view of these results, sonication can be used to modify growth morphology and broth
rheology without affecting growth rate and yield of filamentous fungi. 相似文献
539.
Marta Lombó Paz Herráez 《Biological reviews of the Cambridge Philosophical Society》2021,96(4):1243-1262
Environmental pollution is becoming one of the major concerns of society. Among the emerging contaminants, endocrine-disrupting chemicals (EDCs), a large group of toxicants, have been the subject of many scientific studies. Besides the capacity of these compounds to interfere with the endocrine system, they have also been reported to exert both genotoxic and epigenotoxic effects. Given that spermatogenesis is a coordinated process that requires the involvement of several steroid hormones and that entails deep changes in the chromatin, such as DNA compaction and epigenetic remodelling, it could be affected by male exposure to EDCs. A great deal of evidence highlights that these compounds have detrimental effects on male reproductive health, including alterations to sperm motility, sexual function, and gonad development. This review focuses on the consequences of paternal exposure to such chemicals for future generations, which still remain poorly known. Historically, spermatozoa have long been considered as mere vectors delivering the paternal haploid genome to the oocyte. Only recently have they been understood to harbour genetic and epigenetic information that plays a remarkable role during offspring early development and long-term health. This review examines the different modes of action by which the spermatozoa represent a key target for EDCs, and analyses the consequences of environmentally induced changes in sperm genetic and epigenetic information for subsequent generations. 相似文献
540.
Acid loss in the human duodenum 总被引:2,自引:0,他引:2