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1.
Summary The hyomandibula is an important element of the head and has been influenced in its structural features by different functions. It is roughly T-shaped with vertical and horizontal ridges. In fish, such asMacropodus opercularis, the deep curve at the antero-dorsal end of this ridge may be correlated with the concentrated force applied by the adductor mandibulae muscles. InMacropodus opercularis, the hyomandibula is shorter and broader than that ofAnabas testudineus andCtenopoma acutirostre. In the latter two genera, almost the entire anterior surface of the vertical ridge is uniformly curved, which may be explained by the distributive force applied by the adductor muscles perpendicularly. InMacropodus, the hyomandibulo-interhyal articulation is not straight along the axis of the interhyal as inCtenopoma, but the interhyal makes an angle of 45 to the hyomandibula. This difference might be functional as well as due to the oblique orientation of the hyomandibula. InCtenopoma, the articulating facet of the symplectic is located slightly below the interhyal articulating facet. This might be caused by the location of the hyomandibulo-interhyal articulation. The hyomandibulo-interhyal articulation also helps in the depression of the lower jaw when the latter is depressed by the hyoid bar. Thus, a structural analysis of the hyomandibula and its relationships with functions depict the interrelation between form and function.  相似文献   
2.
Nodulosphaeria is a ubiquitous genus that comprises saprobic, endophytic and pathogenic species associated with a wide variety of substrates and has 64 species epithets listed in Index Fungorum. The classification of species in the genus has been a major challenge due to a lack of understanding of the importance of characters used to distinguish taxa, as well as the lack of reference strains. The present study clarifies the phylogenetic placement of the genus and related species, using fresh collections from Italy. Four Nodulosphaeria species are characterized based on multi-loci analyses of ITS, LSU, SSU, TEF and RPB2 sequence datasets. Phylogenetic analyses indicate that Nodulosphaeria species group within the family Phaeosphaeriaceae as a distinct genus. The sexual morphs of Nodulosphaeria hirta and N. spectabilis are described and illustrated using modern concepts. Two new Nodulosphaeria species are introduced. The phylogenetic relationships and taxonomy of the genus Nodulosphaeria are discussed, but further sampling with fresh collections, reference or ex-type strains and molecular data are needed to obtain a better and natural classification for the genus.  相似文献   
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4.
Interaction of the breast cancer resistance protein with plant polyphenols   总被引:8,自引:0,他引:8  
Multidrug transporters influence drug distribution in vivo and are often associated with tumour drug resistance. Here we show that plant-derived polyphenols that interact with P-glycoprotein can also modulate the activity of the recently discovered ABC transporter, breast cancer resistance protein (BCRP/ABCG2). In two separate BCRP-overexpressing cell lines, accumulation of the established BCRP substrates mitoxantrone and bodipy-FL-prazosin was significantly increased by the flavonoids silymarin, hesperetin, quercetin, and daidzein, and the stilbene resveratrol (each at 30 microM) as measured by flow cytometry, though there was no corresponding increase in the respective wild-type cell lines. These compounds also stimulated the vanadate-inhibitable ATPase activity in membranes prepared from bacteria (Lactococcus lactis) expressing BCRP. Given the high dietary intake of polyphenols, such interactions with BCRP, particularly in the intestines, may have important consequences in vivo for the distribution of these compounds as well as other BCRP substrates.  相似文献   
5.
The genus Fusariella, typified by F. atrovirens, is characterised by semi- to macronematous, mononematous conidiophores, with cylindrical, subulate or lageniform phialidic conidiogenous cells that produce catenate, septate, curved to straight, subhyaline to brown conidia. During a survey of hyaline-spored hyphomycetes from karst areas in Thailand, we collected a new species of Fusariella with curved conidia and introduce it in this paper as Fusariella curvata sp. nov. In addition, all hitherto described species of Fusariella are reviewed. The result of phylogenetic analyses, based on combined SSU, LSU, TEF and RPB2 sequence data, indicates that the genus belongs in the family Bionectriaceae (Hypocreales, Sordariomycetes).  相似文献   
6.
One hundred E. coli isolates from Norway (n = 37), Sweden (n = 24), UK (n = 20) and Spain (n = 19), producing CTX-M-type - (n = 84), or SHV-12 (n = 4) extended spectrum β-lactamases, or the plasmid mediated AmpC, CMY-2 (n = 12), were typed using multi-locus sequence typing (MLST) and multi-locus variable number of tandem repeat analysis (MLVA). Isolates clustered into 33 Sequence Types (STs) and 14 Sequence Type Complexes (STCs), and 58 MLVA-Types (MTs) and 25 different MLVA-Type Complexes (MTCs). A strong agreement between the MLST profile and MLVA typing results was observed, in which all ST131-isolates (n = 39) and most of the STC-648 (n = 10), STC-38 (n = 9), STC-10 (n = 9), STC-405 (n = 8) and STC-23 (n = 6) isolates were clustered distinctly into MTC-29, -36, -20, -14, -10 and -39, respectively. MLVA is a rapid and accurate tool for genotyping isolates of globally disseminated virulent multidrug resistant E. coli lineages, including ST131.  相似文献   
7.
The functional and structural aspects of the suspensorium of Ctenopoma acutirostre have been correlated with those of Anabas testudineus. The different parts of the suspensorium are described, as are the muscles that are functionally connected with the suspensorium. Functions were analyzed by observations on living specimens, and by measurements recorded from the movie films. The role played by various bones and muscles to carry out the functions (the respiration, the gulping, and the feeding) has been explained. The different bones and muscles have been considered as functional units which often are connected to form couplings. During the respiration in Ctenopoma the depression of the lower jaw is conducted by the levator operculiopercular apparatus-mandible coupling. The presence of this coupling is indicated by the presence of dorso-ventral movement of the operculum. A remarkable ventro-dorsal and antero-caudal movement in the urhyal during feeding shows in Ctenopoma the presence of the sternohyoideus-hyoid apparatus-interopercular-mandible coupling, which depresses the lower jaw. In Ctenopoma, the suspensorium takes part in respiration, gulping, and feeding, whereas in Anabas it is only involved in gulping and feeding. To carry out its functions, the suspensorium implies three articulations: palatocranial, craniohyomandibular, and quadratomandibular with the cranium and the lower jaw, respectively. Finally, the suspensorium has been analyzed as a part of the architectonic structure of the entire head by using a diagrammatic model (fig. 13) based on mutual influence, integration, and couplings.  相似文献   
8.
Reducing infarct size during a cardiac ischaemic-reperfusion episode is still of paramount importance, because the extension of myocardial necrosis is an important risk factor for developing heart failure. Cardiac ischaemia-reperfusion injury (IRI) is in principle a metabolic pathology as it is caused by abruptly halted metabolism during the ischaemic episode and exacerbated by sudden restart of specific metabolic pathways at reperfusion. It should therefore not come as a surprise that therapy directed at metabolic pathways can modulate IRI. Here, we summarize the current knowledge of important metabolic pathways as therapeutic targets to combat cardiac IRI. Activating metabolic pathways such as glycolysis (eg AMPK activators), glucose oxidation (activating pyruvate dehydrogenase complex), ketone oxidation (increasing ketone plasma levels), hexosamine biosynthesis pathway (O-GlcNAcylation; administration of glucosamine/glutamine) and deacetylation (activating sirtuins 1 or 3; administration of NAD+-boosting compounds) all seem to hold promise to reduce acute IRI. In contrast, some metabolic pathways may offer protection through diminished activity. These pathways comprise the malate-aspartate shuttle (in need of novel specific reversible inhibitors), mitochondrial oxygen consumption, fatty acid oxidation (CD36 inhibitors, malonyl-CoA decarboxylase inhibitors) and mitochondrial succinate metabolism (malonate). Additionally, protecting the cristae structure of the mitochondria during IR, by maintaining the association of hexokinase II or creatine kinase with mitochondria, or inhibiting destabilization of FOF1-ATPase dimers, prevents mitochondrial damage and thereby reduces cardiac IRI. Currently, the most promising and druggable metabolic therapy against cardiac IRI seems to be the singular or combined targeting of glycolysis, O-GlcNAcylation and metabolism of ketones, fatty acids and succinate.  相似文献   
9.
Summary Escherichia coli was continuously cultivated in a disc turbine agitated laboratory fermenter at constant dilution rate under conditions of carbon limitation. Agitation rate (impeller speed) was varied over the range 600 to 1500 rev. min-1. As previously reported, the mean cell volume was found to increase linearly with increase in agitation rate, whereas total cell counts and dry cell weights remained constant. Measurements of intracellular sodium and potassium concentration showed that these both increased as the cell volume increased: the potassium content was about twenty times the sodium content and the intracellular content of each ion doubled over the range of agitation rates tested.  相似文献   
10.
ABSTRACT: BACKGROUND: Vascular elasticity is crucial for maintaining hemodynamics. Molecular mechanisms involved in human elastogenesis are incompletely understood. We describe a syndrome of lethal arteriopathy associated with a novel, identical mutation in the fibulin 4 gene (FBLN4) in a unique cohort of infants from South India. METHODS: Clinical characteristics, cardiovascular findings, outcomes and molecular genetics of twenty-two infants from a distinct population subgroup, presenting with characteristic arterial dilatation and tortuosity during the period August 2004 to June 2011 were studied. RESULTS: Patients (11 males, 11 females) presented at median age of 1.5 months, belonging to unrelated families from identical ethno-geographical background; eight had a history of consanguinity. Cardiovascular features included aneurysmal dilatation, elongation, tortuosity and narrowing of the aorta, pulmonary artery and their branches. The phenotype included a variable combination of cutis laxa (52 %), long philtrum-thin vermillion (90 %), micrognathia (43 %), hypertelorism (57 %), prominent eyes (43 %), sagging cheeks (43 %), long slender digits (48 %), and visible arterial pulsations (38 %). Genetic studies revealed an identical c.608A > C (p. Asp203Ala) mutation in exon 7 of the FBLN4 gene in all 22 patients, homozygous in 21, and compound heterozygous in one patient with a p. Arg227Cys mutation in the same conserved cbEGF sequence. Homozygosity was lethal (17/21 died, median age 4 months). Isthmic hypoplasia (n = 9) correlated with early death (<=4 months). CONCLUSIONS: A lethal, genetic disorder characterized by severe deformation of elastic arteries, was linked to novel mutations in the FBLN4 gene. While describing a hitherto unreported syndrome in this population subgroup, this study emphasizes the critical role of fibulin-4 in human elastogenesis.  相似文献   
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