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41.
D R Blanco J D Radolf M A Lovett J N Miller 《Journal of immunology (Baltimore, Md. : 1950)》1986,137(9):2973-2979
Treponemicidal activity against Treponema pallidum, Nichols strain, by anti-endoflagellar antibodies and the presence of antigenic interrelationships between the endoflagella of Treponema phagedenis biotype Reiter (TPR) and T. pallidum have been demonstrated. SDS-PAGE profiles of purified endoflagella from both organisms were similar, identifying five polypeptide bands for TPR (37,000, 33,000 doublet, 30,000, and 27,000 daltons) and five polypeptide bands for T. pallidum (35,000, 33,000 doublet, 30,000, and 27,000 daltons). Antiserum against TPR endoflagella identified identical bands on Western blots of TPR, T. pallidum, and the respective endoflagellar preparations. Western blots confirmed the presence of antibodies in normal human serum (NHS) against the 33,000 dalton treponemal endoflagellar proteins. The complement-dependent treponemicidal activity of NHS against T. pallidum was completely removed by absorption with purified TPR endoflagella. Furthermore, rabbit antisera against TPR endoflagella were reactive in the Treponema pallidum immobilization (TPI) test. These findings demonstrate that anti-endoflagellar antibodies are treponemicidal against T. pallidum. A possible mechanism for this activity is discussed in relation to the subsurface location of endoflagella. 相似文献
42.
HOST-PLANT RELATIONSHIPS IN THE PAPILIONIDAE (LEPIDOPTERA): PARALLEL CLADOGENESIS OR COLONIZATION? 总被引:1,自引:0,他引:1
James S. Miller 《Cladistics : the international journal of the Willi Hennig Society》1987,3(2):105-120
Abstract— Stepwise coevolution, as defined by Ehrlich and Raven (1964) and others, can be equated with parallel cladogenesis or association by descent (Mitter and Brooks, 1983). I review the insect/plant literature and discuss recent cladistic findings for the Papilionidae, and compare two contrasting theories: 1) that insect/host associations have evolved through parallel cladogenesis; or 2) that insects have 'colonized' their hosts subsequent to plant cladogenesis. I conclude that no documented examples of parallel cladogenesis between insects and plants are known. The swallowtail cladograms instead offer evidence in support of the second theory. They suggest that host association patterns in the Papilionidae have resulted from repeated colonization of plants belonging to a relatively small number of families. I discuss data which indicate that plant secondary chemicals have been important 'barriers' to colonization ( sensu Ehrlich and Raven, 1964), and have in large part mediated host switching in the Papilionidae. 相似文献
43.
C D Wolleben R K McPherson J Rulfs G L Johnson T B Miller 《Biochimica et biophysica acta》1987,928(1):98-106
The phosphorylation of glycogen synthase has been studied in freshly isolated adult rat cardiomyocytes. Six peaks of 32P-labeled tryptic peptides are recovered via C-18 high performance liquid chromatography (HPLC) when synthase is immunoprecipitated from 32P-labeled cardiomyocytes and digested with trypsin. When epinephrine treated cells are used as a source of enzyme, the same HPLC profile is obtained with a dramatic enhancement of 32P recovered in two of the HPLC peaks. In vitro phosphorylation of rat heart synthase by cAMP-dependent protein kinase stimulates the conversion of synthase from the I to the D form and results in the recovery of the same tryptic peptides from the C-18 as is the case for synthase derived from cardiomyocytes. Treatment of cAMP-dependent kinase phosphorylated synthase with protein phosphatase-1 leads to a reactivation of the enzyme and a dephosphorylation of the same tryptic peptides that are selectively phosphorylated in epinephrine treated cardiomyocytes. These results are discussed in relation to hormonal control of glycogen metabolism in cardiac tissue. 相似文献
44.
45.
The relationship between aldosterone production and prostaglandin E2 synthesis was evaluated using the responses of isolated rat adrenal glomerulosa cells to angiotensin II, ACTH and potassium. Simultaneous PGE2 and aldosterone measurements were made during timed incubations with these stimuli, and in incubations with arachidonic acid, meclofenamate, indomethacin, and aminoglutethamide. PGE2 and aldosterone production were assessed by radioimmunoassay. We were not able to demonstrate stimulation of PGE2 by angiotensin II, ACTH, or potassium despite significant increments in aldosterone production with these stimuli. Arachidonic acid enhanced PGE2 synthesis, but had no effect on aldosterone release. Indomethacin and meclofenamate inhibited aldosterone secretion. Aminoglutethimide depressed aldosterone production, but had little effect on PGE2 levels in the media.These studies demonstrate that dienoic prostaglandins play no direct role in aldosterone production stimulated by angiotensin II, ACTH, or potassium in rat adrenal glomerulosa cells. Since inhibitors of cyclo-oxygenase decreased aldosterone synthesis, it is possible that fatty acids other than arachidonic acid may be cyclo-oxygenated to products which regulate aldosterone production. 相似文献
46.
N E Miller 《Biofeedback and self-regulation》1985,10(1):3-24
This paper will deal with a variety of topics such as dangers and opportunities from the developing crisis in health care costs, a cooperative study of the cost-effectiveness of treatments for headaches, the need for a federation of related societies, exploiting remarkable electronic advances, the wide range of adaptive functions of visceral learning (including its role in homeostasis), why maladjustments occur and their implications for biofeedback, and the need for analytic experiments involving adequate amounts of training. 相似文献
47.
Isolation and sequence analysis of cDNA clones coding for rat skeletal muscle creatine kinase 总被引:11,自引:0,他引:11
P A Benfield R A Zivin L S Miller R Sowder G W Smythers L Henderson S Oroszlan M L Pearson 《The Journal of biological chemistry》1984,259(23):14979-14984
A series of cDNA clones corresponding to 1494 bases of rat muscle creatine kinase mRNA has been isolated and characterized. The identity of these clones has been confirmed by DNA sequence analysis and by comparison of the predicted amino acid sequence with that determined for the purified protein. The cDNA sequence accounts for the entire coding sequence of the creatine kinase protein in addition to the complete 3' untranslated region and 68 bases of 5' noncoding region. Sequences corresponding to the active site region of the protein, the initiation codon, the termination codon, and poly(A) addition signal have been identified. 相似文献
48.
The isolation and identification of a material present in the plasma of hypertensive dogs and hypertensive human patients has been under study since 1972. The earliest experiments in relation to this work, noted that plasma from hypertensive dogs cause a hyperresponse to norepinephrine when both were administered by way of the vein. Employing a rat assay system that consisted of an anesthetized rat with polyethylene catheters in the vein for giving norepinephrine and the test fractions and a catheter in the artery for blood pressure monitoring, fractions from hog kidney were tested for hyperresponsiveness activity. The active material is very comparable to cyclic AMP in molecular weight, ultraviolet spectrum, paper chromatography, Enzyme hydrolysis and activity in the anesthetized rat system. This evidence indicates that the hyperresponsiveness factor of renal origin is cyclic AMP. 相似文献
49.
Analysis of antigenic types appearing in first relapse populations of clones of Trypanosoma brucei 总被引:18,自引:0,他引:18
Variant antigenic types (VATs) represented in a total of 47 first relapse populations of 6 clones of Trypanosoma brucei LUMP 227 were identified by immunofluorescent staining of living trypanosomes, using antiserum raised against purified surface antigens. The relative growth rates of these 6 clones were measured both individually and when grown together in a mixed population, and were found to be different under these two sets of conditions. A pattern emerged in the VATs represented in relapses of each clone, with some types being expressed more frequently than others and certain VATs being only very rarely expressed. It is suggested that new VATs are expressed according to a statistically definable order of priority which is different for each parent VAT, and that some VATs may be able to change to certain others only after passing through an intermediate VAT. The order of priority of appearance of VATs does not appear to correlate with growth rate measured either in individual clones or when clones are grown in a mixed population. 相似文献
50.
Deletion of the gag region from FBR murine osteosarcoma virus does not affect its enhanced transforming activity. 总被引:1,自引:1,他引:0 下载免费PDF全文
Both FBJ murine osteosarcoma virus (FBJ-MSV) and FBR-MSV induce transformation in tissue culture and osteogenic sarcomas in mice. In tissue culture, however, FBR-MSV induces larger foci with a shorter latency than those induced by FBJ-MSV. Transformation is dependent on expression of the fos oncogene in FBJ-MSV and of a gag-fos fusion protein in FBR-MSV. We have determined that the gag sequences can be deleted from FBR-MSV without affecting the high transforming activity of this virus in comparison to FBJ-MSV. The resultant virus, designated FBJ/R-MSV, has a protein coding region that is half the size of that of FBR-MSV and about one-third smaller than that of FBJ-MSV. Thus, FBJ/R-MSV will provide a useful tool for studying the transforming activity of the fos oncogene. 相似文献