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21.
J E Kendrick G L Matson 《Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine (New York, N.Y.)》1975,149(1):158-162
Stimulation of both CSN in dogs with continuous stimuli decreased blood pressure and heart rate as effectively as intermittent bursts of stimuli. The temporal separation between the stimulus bursts to the two CSN was without effect on the reflex response. Similarly perfusion of both carotid sinuses with pressure pulses which were in phase was no more effective in eliciting the reflex than perfusion with pressure pulses 180 degree out of phase. These results suggest that the barosensory fibers project centrally to independent neuronal pools. Pulsatile perfusion of the carotid sinuses lowered systemic pressure more than nonpulsatile pressure at the same mean level. The greater efficacy of pulsatile pressure appears to result from baroreceptor recruitment and not from the impulse pattern. 相似文献
22.
The ability of Gram-negative lipopolysaccharide (LPS) to function as an adjuvant and as an antigen in IgE and IgG1 immune responses in mice was investigated. LPS failed to induce LPS-specific IgE or IgG1 under a variety of experimental conditions. Both isolated LPS and whole heat-killed bacteria were capable of enhancing IgE and IgG1 antibody formation to a protein antigen, egg albumin (EA). The LPS-induced anti-EA, IgE, and IgG1 antibody titers exhibited a cycling phenomenon with time. In the presence of LPS, IgE, and IgG1 antibodies specific for EA did not occur in athymic nude (BALB/c-nu/nu) mice, demonstrating the inability of LPS to substitute for the stringent requirement for T cells in homocytotropic antibody formation. 相似文献
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Pamela B. Moore Darrell R. Anderson John W. Huggins Kermit L. Carraway 《Biochemical and biophysical research communications》1976,72(1):288-294
Membrane envelopes prepared from Zn++-treated Sarcoma 180 cells contain polypeptides which appear to be related to the putative cellular cytoskeletal elements responsible for control of cell shape and motility. These include actin, myosin, α-actinin and a large polypeptide (mol wt 250,000) with some similarities to spectrin of the erythrocyte membrane. If the envelopes are vesiculated by extraction with alkaline EDTA solutions at low ionic strength, four major polypeptides are released, including the actin and spectrin-like materials; myosin is not extracted. The stabilized envelopes offer a useful source of material for the characterization of cytoskeletal elements and for the investigation of their associations with the membrane. 相似文献
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C. W. H. Havard Lawrence P. Garrod Pamela M. Waterworth 《BMJ (Clinical research ed.)》1959,1(5123):688-689
26.
Pamela J. Woods 《Environmental Biology of Fishes》2010,88(2):153-168
Correlations of feeding morphology with body morphology reflect ecological variation of a species and the geographic or ontogenetic
scales over which it occurs. In this study, evidence was found for geographic variation in lower pharyngeal jaw (LPJ) morphology
of Cymatogaster aggregata Gibbons (Embiotocidae, Teleostei) in the Pacific Northwest, U.S.A. Correlations of LPJ morphology with body morphology were
more obvious in adulthood than the juvenile stage. Morphological patterns corresponded better with environmental variables
and gut contents than geographic proximity, indicating that they were most likely caused by habitat differences. Qualitative
common garden experiments indicated the nature and direction of plastic responses, and indicate a likely plastic origin to
most naturally observed differences. Recognizing ecological patterns via morphology is an important first step in understanding
how and when ecological mechanisms influence the functional role of an organism within its environment. 相似文献
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Chris V. Bowen Drew DeBay H. Stephen Ewart Pamela Gallant Sean Gormley T. Toney Ilenchuk Umar Iqbal Tyler Lutes Marzia Martina Geoffrey Mealing Nadine Merkley Sandra Sperker Maria J. Moreno Christopher Rice Raymond T. Syvitski John M. Stewart 《PloS one》2013,8(3)
Soricidin is a 54-amino acid peptide found in the paralytic venom of the northern short-tailed shrew (Blarina brevicauda) and has been found to inhibit the transient receptor potential of vallinoid type 6 (TRPV6) calcium channels. We report that two shorter peptides, SOR-C13 and SOR-C27, derived from the C-terminus of soricidin, are high-affinity antagonists of human TRPV6 channels that are up-regulated in a number of cancers. Herein, we report molecular imaging methods that demonstrate the in vivo diagnostic potential of SOR-C13 and SOR-C27 to target tumor sites in mice bearing ovarian or prostate tumors. Our results suggest that these novel peptides may provide an avenue to deliver diagnostic and therapeutic reagents directly to TRPV6-rich tumors and, as such, have potential applications for a range of carcinomas including ovarian, breast, thyroid, prostate and colon, as well as certain leukemia''s and lymphomas. 相似文献
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