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91.
92.
Ferdinand Bohlmann Antoinette Suwita Jasmin Jakupovic Robert M. King Harold Robinson 《Phytochemistry》1981,20(7):1649-1655
The investigation of two further Trixis species afforded five new sesquiterpenes related to trixikingolide, six new germacrene derivatives and a sesquiterpene derived from rotundene. Some further known compounds were isolated too, which in part may be of chemotaxonomic significance. The structures were elucidated by spectroscopic methods and a few chemical transformations. The relative position of the ester groups in eight of the new sesquiterpenoids however, could not be established with certainty as partial saponifications were not successful. 相似文献
93.
A. Delibes C. Otero F. García-Olmedo F. Dosba 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1981,60(1):5-10
Summary The distribution of three biochemical markers, U-1, CM-4 and Aphv-a, -b, among wheat-Aegilops addition lines carrying Mv chromosomes from Aegilops ventricosa (genomes DvMv) has been investigated. Addition lines which had been previously grouped together on the basis of common non-biochemical characters carried marker U-1, a protein component from the 2M urea extract. The added chromosome, in the appropriate genetic background, seems to confer a high level of resistance to the eyespot disease, caused by the fungus Cercosporella herpotrichoides. The other two markers were concomitantly associated with another similarly formed group of addition lines. Both CM-4, a protein component from the chloroform:methanol extract, and Aphv-a, -b, alkaline phosphate isozymes, have been previously shown to be associated with homoeologous chromosome group 4, which suggests that the added chromosome in the second group of addition lines is 4Mv. 相似文献
94.
Ferdinand Bohlmann Jürgen Ziesche Robert M. King Harold Robinson 《Phytochemistry》1980,19(12):2675-2679
The investigation of two further Senecio species and the re-investigation of S. inaequidens afforded, in addition to known compounds, seven new furanoeremophilane derivatives. Six of these are closely related to cacalol, a sesquiterpene type which predominates in the species investigated. 相似文献
95.
Ferdinand Bohlmann Christa Zdero Robert M. King Harold Robinson 《Phytochemistry》1980,19(12):2663-2668
The investigation of three Eremanthus species afforded, in addition to known compounds, several new sesquiterpenelactones, a cumambrin B isobutyrate, four lactones related to the eremantholides, two to zexbrevin and one to goyazensolide. Furthermore, a new coniferyl alcohol derivative was isolated. The overall picture of the genus is very uniform. The occurrence of eremanthine and germacranolides with a furanone ring seems to be especially typical. 相似文献
96.
Franco Pandolfi Douglas M. Strong Guy D. Bonnard Ronald B. Herberman 《In vitro cellular & developmental biology. Plant》1980,16(9):754-760
Summary Four hematopoietic cell lines (CCRF-CEM, HSB-2, MOLT-4, and RPMI-8402), derived from acute lymphoblastic leukemia and expressing
T-cell surface markers (T-HCL), were studied with two specific anti-T-cell sera. The sera were raised in rabbits against human
thymocytes (anti-HTY) and against T-cells cultured in the presence of conditioned medium derived from lymphocytes stimulated
with PHA (anti-CTC). Both sera were absorbed to obtain a T-cell specific pattern of reaction and were further absorbed with
normal peripheral blood lymphocytes or with each of the four T-HCL. The anti-HTY sera absorbed with CEM, 8402, and HSB-2 still
reacted with MOLT-4. A similar pattern of reactivity was found only with the anti-CTC absorbed with 8402, whereas, after absorptions
with the other cell lines, this antiserum was unreactive against MOLT-4. After absorption with normal peripheral blood lymphocytes,
anti-HTY still reacted with thymocytes and MOLT-4 but was negative on CTC. In contrast, anti-CTC absorbed with peripheral
blood lymphocytes (PBL) was negative on thymocytes and MOLT-4 but still reacted against CTC. Our data confirm the existence
of a T-cell antigen (probably an early T-cell differentiation antigen) shared between thymus and MOLT-4. This antigen is not
expressed on CTC, although these cells express an antigenic pattern more complex than PBL. Antisera to CTC represents a source
of anti-T-cell sera free of contamination with antibodies to early thymus-related antigens but containing other T-cell-related
specificities.
Supported in part by Naval Medical Research and Development Command, Research Task No. ZF51.524.013.1025, and National Cancer
Institute Contract No. Y01-CB-00319. The opinions and assertions contained herein are the private ones of the writers and
are not to be construed as official or reflecting the views of the Navy Department or the naval service at large. The experiments
reported herein were conducted according to the principles set forth in the current edition of the “Guide for the Care and
Use of Laboratory Animals,” Institute of Laboratory Animal Resources, National Research Council. 相似文献
97.
Kinetics of drug-DNA interaction. Dependence of the binding mechanism on structure of the ligand 总被引:2,自引:0,他引:2
Kinetic and equilibrium studies of the binding of several phenanthridines and acridines to DNA have been performed to investigate the physical processes underlying the direct ligand transfer mechanism of drug-DNA interaction· Substitution of the 6-phenyl ring of dimidium with a p-carboxyl residue, or complete removal of either the 6-substituent or the 3-amino group, does not prevent the phenanthridine chromophore from transferring directly between binding sites. Loss of the aromatic ring increases association rate constants three- to ninefold and enhances dissociation rates by factors of up to 12; the rates of direct transfer and dissociation from site 1 are the most perturbed. The presence of a phenyl ring stabilizes the site 1 complex and lowers the binding constant to site 2. Introduction of the p-carboxyl group does not affect the equilibrium distribution of bound forms but produces equivalent increases (2·5-fold) in forward and reverse rate constants for binding to site 1 and for the direct transfer step. The 3-amino group greatly stabilizes the site 1 complex. Its removal accelerates all kinetic processes except for the reverse transfer step; the transfer rate is enhanced 25-fold and binding to site 2 is increased 12-fold. The dissociation rate from site 1 rises by a factor of 45 and that from site 2 by a factor of 5·8.10-Methyl-9-aminoacridine binds via the direct transfer pathway with rate and equilibrium constants similar to those of the 3-desamino derivative of ethidium. This compound provides the first fully characterized example of an acridine that utilizes bimolecular transfer. By contrast, rivanol (6,9-diamino-2-ethoxyacridine) interacts with DNA via a two-step sequential mechanism analogous to that seen with proflavine, yet its intrinsic association constant is three times higher. This results from tighter ‘external’ attachment to the helix, together with a decrease in equilibrium constant for the insertion step, which is markedly slower than that of proflavine. There appears to be a simple relation between the apparent enthalpy of binding and the number of extracyclic amino substituents on the intercalating chromophore.We propose that the two bound forms that participate in direct ligand transfer represent molecules intercalated via one or other of the grooves of DNA, and that the transfer pathway corresponds to exchange of drug between the wide groove of one helix and the narrow groove of another. The ability to form strongly bound complexes at the surface of the helix appears to play a major role in determining the mechanism of ligand binding. 相似文献
98.
K. Hála J. Plachy H. Kní?etov#xE; B. Kní?e A. Stratil J. Derka 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1979,55(3-4):113-117
Summary Comparison of two inbred chicken lines (Fx > 99.9%) revealed significant differences in shape of the red blood cells (RBC). The length-width index was lower for both sexes in IC-line (1.46) when compared to CB-line chickens (1.88). Phenotypic expression of this character in F1 hybrids and both backcross groups corresponded to the common manifestations of the metric parameters. The index in F1 hybrid chickens deviated from intermediate values with the dominant tendency to oval RBC. An analysis of the segregating first backcross generation chickens did not show any association between RBC shape and the genotype in the blood group systems B, C, I, and D and the IgG allotypes. The differences in RBC shape were probably not associated with the survival of RBC in the blood circulation. 相似文献
99.
Abla A. Creasey Helene S. Smith Adeline J. Hackett Kimie Fukuyama William L. Epstein Stewart H. Madin 《In vitro cellular & developmental biology. Plant》1979,15(5):342-350
Summary Three human melanoma cell lines derived from one primary and two metastatic tumors from three different patients were characterized
for growth properties usually associated with malignant transformation; these include cell morphology, growth rate, saturation
density, growth in semisolid media, colony-forming ability on contact-inhibited monolayers of normal fibroblasts and epithelial
cells, and tumorigenicity in immunosuppressed mice. Variations in expression of aberrant properties were evident among the
lines. One of the metastatic lines satisfied all the parameters of malignancy tested and the other showed a number of these
properties, whereas the primary essentially fulfilled only one. These results suggest that cultured melanoma cells reflect
the clinical variability often observed among melanoma patients and the metastatic melanoma seems to display a higher degree
of malignant transformation than the primary.
THis work was supported in part by USPHS Grant No. 5 T01 AI00332-06 from the National Institutes of Health, Contract E73-2001-N01-CP-3-3237
from the Virus Cancer Program of the National Cancer Institute, and USPHS Grant No. 0H00714-02 from the National Institute
for Occupational Safety and Health. 相似文献
100.
A. Debec 《Development genes and evolution》1976,180(2):107-119
Summary Our previous isoenzyme investigation ofDrosophila melanogaster cell lines in vitro has been completed with twelve further enzyme systems. The enzyme profiles seem to be in good agreement with a previous hypothesis concerning the precise origin of these cell lines (probably from imaginal discs or nervous tissues). Our results have been summarized with reference to the biochemical genetic map ofDrosophila melanogaster in order to consider a possible functional organization of the genome.Abbreviations NAD
nicotine adenine nucleotide
- NADP
nicotine adenine nucleotide phosphate
- NBT
nitroblue tetrazolium
- PMS
phenazine methosulfate
- EDTA
ethylene diamine tetraacetic acid
- GOT
Glutamate-oxaloacetate transaminase
- PGK
Phosphoglycerate kinase
- GPDH
-glycerophosphate dehydrogenase
- MDH
Malate dehydrogenase
- PGM
Phosphoglucomutase
- Aph
Alkaline phosphatase
- MDH-NADP
Malic enzyme
- Lap
Leucine Amino-Peptidase
- LDH
Lactate dehydrogenase
- -1-OHDH
L-3-hydroxyacid dehydrogenase
- ADH
Alcohol dehydrogenase
- Aldox
Aldehyde oxydase
- 6PGD
6 Phosphogluconate dehydrogenase
- G6PD
Glucose-6-Phosphate dehydrogenase
- Hex3
Fructokinase
- IDH
Isocitrate dehydrogenase
- Est 6
Esterase 6
- Est C
Esterase C
- ODH
Octanol dehydrogenase
- XDH
Xanthine dehydrogenase
- AcPh
Acid Phosphatase 1 相似文献