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991.
Studies of gastric morphology in North American Chiroptera (Emballonuridae, Noctilionidae, and Phyllostomatidae) 总被引:1,自引:0,他引:1
G L Forman 《Journal of mammalogy》1973,54(4):909-923
992.
993.
Andrew Leask 《Journal of cell communication and signaling》2010,4(1):73-74
Connective tissue growth factor (CTGF/CCN2) is overexpressed in diabetes. Diabetic rats possess myocardial and cardiomyocyte hypertrophy. In a recent report, Wang and colleagues (Am J Physiol Cell Physiol. 2009 Jul 22. [Epub ahead of print]) show that CCN2 directly mediates cardiomyocyte hypertrophy as well as that induced by high glucose and fatty acid. CCN2 acted via the TrkA receptor. These data are the subject of this commentary, and emphasize that CCN2 may be an excellent target for therapy in diabetes. 相似文献
994.
Five new species of Passiflora subgenera Plectostemma and Tacsonia from Ecuador are described, viz. P. discophora, P. monadelpha, P. subpurpurea, P. hirtiflora and P. sanctaebarbarae . Section Discophora of subg. Plectostemma is proposed. 相似文献
995.
New methods of analysing genetic data provide powerful tools for quantifying dispersal patterns and reconstructing population
histories. Here we examine the population structure of the bumblebee Bombus hortorum in a model island system, the Western Isles of Scotland, using microsatellite markers. Following declines in other species,
B. hortorum is the only remaining long-tongued bumblebee species found in much of Europe, and thus it is of particular ecological importance.
Our data suggest that populations of B. hortorum in western Scotland exist as distinct genetic clusters occupying groups of nearby islands. Population structuring was higher
than for other bumblebee species which have previously been studied in this same island group (Fst = 0.16). Populations showed significant isolation by distance. This relationship was greatly improved by using circuit theory
to allow dispersal rates to differ over different landscape features; as we would predict, sea appears to provide far higher
resistance to dispersal than land. Incorporating bathymetry data improved the fit of the model further; populations separated
by shallow seas are more genetically similar than those separated by deeper seas. We argue that this probably reflects events
following the last ice age when the islands were first colonized by this bee species (8,500–5,000 ybp), when the sea levels
were lower and islands separated by shallow channels would have been joined. In the absence of significant gene flow these
genetic clusters appear to have since diverged over the following 5,000 years and arguably may now represent locally adapted
races, some occurring on single islands. 相似文献
996.
R D Gavriliaka N A Semina L I Fiks S V Shabalina N V Tsvetkova 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1985,(1):45-48
ELISA is used for detecting the soluble staphylococcal antigen in patients with purulent septic infections. The optimum conditions for the assay have been established: the dose of staphylococcal gamma globulin for plate sensitization should be 5.0-10.0 micrograms/ml, the pH of the buffer solution 9.6-10.0, the time and temperature of incubation 18-20 hours at 4 degrees C or 5 hours at 37 degrees C. The possibility of using plates manufactured in the USSR has been shown. The sensitivity of the above diagnostic test system is 0.005 microgram/ml. 相似文献
997.
Somatic embryogenesis and plantlet formation were obtained from 60–75 day old cell cultures of carnation. Callus was generated on MS basal medium supplemented with 2,4-dichchlorophenoxy acetic acid (2,4-D). Removal of 2,4-D during subsequent subculturing of cell suspensions resulted in formation of embroids. These somatic embryos originated from single cells and their early development proceeded normally with clearly defined apical and root meristems. Some embryos developed into plants and were acclimatized to ex vitro conditions. 相似文献
998.
Role of different lymphoid tissues in the initiation and maintenance of DNA-raised antibody responses to the influenza virus H1 glycoprotein. 下载免费PDF全文
Antibody responses in mice immunized by a single gene gun inoculation of plasmid expressing the influenza virus H1 hemagglutinin and in mice immunized by a sublethal H1 influenza virus infection have been compared. Both immunizations raised long-lived serum responses that were associated with the localization of antibody-secreting cells (ASC) to the bone marrow. However, the kinetics of these responses were 4 to 8 weeks slower in the DNA-immunized than in the infection-primed mice. Following a gene gun booster, the presence of ASC in the inguinal lymph nodes, but not in other lymph nodes, revealed gene gun responses being initiated in the nodes that drain the skin target site. Both pre- and postchallenge, the DNA-immunized mice had 5- to 10-times-lower levels of antibody and ASC than the infection-primed mice. 相似文献
999.
1000.
P. Gerrans 《Biology & philosophy》2007,22(1):35-56
Delusions are currently characterised as false beliefs produced by incorrect inference about external reality (DSM IV). This
inferential conception has proved hard to link to explanations pitched at the level of neurobiology and neuroanatomy. This
paper provides that link via a neurocomputational theory, based on evolutionary considerations, of the role of the prefrontal
cortex in regulating offline cognition. When pathologically neuromodulated the prefrontal cortex produces hypersalient experiences
which monopolise offline cognition. The result is characteristic psychotic experiences and patterns of thought. This bottom-up
account uses neural network theory to integrate recent theories of the role of dopamine in delusion with the insights of inferential
accounts. It also provides a general model for evolutionary psychiatry which avoids theoretical problems imported from evolutionary
psychology. 相似文献