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91.
Vidmantas A. Raisys Patrick N. Friel Patricia R. Graaff Kent E. Opheim Alan J. Wilensky 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1980,183(4)
A one-step method for extraction of diazepam, nordiazepam, and internal standard into toluene is followed by chromatographic separation and detection with either dual-wavelength high-performance liquid chromatography or electron-capture gas—liquid chromatography. Agreement between the two methods was excellent for diazepam (r = 0.99, n = 38) and good for nordiazepam (r = 0.96, n = 79) over a concentration range that included subtherapeutic, therapeutic, and toxic plasma levels. 相似文献
92.
R L Smith N H Hunt J E Merritt T Evans M J Weidemann 《Biochemical and biophysical research communications》1980,96(3):1079-1087
The production of reactive oxygen species by elicited rat peritoneal macrophages was assessed by measurement of chemiluminescence in the presence of luminol. The divalent ion ionophore A23187 stimulated the production of reactive oxygen species. This action was inhibited by monobutyryl and dibutyryl derivatives of cyclic AMP but was not affected by derivates of cyclic GMP. Cyclic AMP and cyclic GMP concentrations increased rapidly in macrophages exposed to A23187 or zymosan. Indomethacin (20 μmol/1) inhibited the increase in cyclic AMP concentration but not the increase in cyclic GMP concentration. Neither A23187 nor zymosan stimulated adenylate cyclase activity in broken cell preparations of macrophages. The observations are consistent with the hypothesis that PGE produced by macrophages after phagocytotic stimuli may inhibit certain macrophage functions and perform a regulatory role in these cells. This action of PGE may be mediated by cyclic AMP. 相似文献
93.
Caulanthus barnebyi from northern Nevada is described, illustrated, and compared with its nearest relative,C. glaucus S. Wats. 相似文献
94.
Lois T. Hunt Margaret O. Dayhoff 《Biochemical and biophysical research communications》1980,95(2):864-871
A distant relationship between chicken ovalbumin and two human plasma protease inhibitors was revealed by computer analyses. We propose a new protein superfamily containing at least three families: ovalbumin (and probably gene X and gene Y proteins), antithrombin-III, and alpha1-proteinase inhibitor. Although these families may have diverged from a common ancestor more than 500 million years ago, they may still share similarity in gene structure as well as in protein sequence. 相似文献
95.
Asclepias welshii, restricted to the Coral Pink Sand Dunes of southern Utah, is described and illustrated. Its relationship to other species of seriesRoseae is discussed. 相似文献
96.
97.
Recombining right nasal half-eyes with left temporal half-eyes at embryonic stage 32 in Xenopus produces a double or “twinned” pattern of functional connections between retina and midbrain optic tectum. The left temporal half-eye is reprogrammed such that it projects to the tectum as a mirror-image duplicate pattern of the nasal right half-eye; both half-eyes project across the entire tectum. However, recombining a right nasal half-eye (in situ) with a right dorsal half-eye (grafted into the temporal position; NRDR eye) produces a single normal retinotectal projection. Where interactions between NR and TL involve both axial reprogramming and duplication of NR positional values in TL, NRDR interactions involve axial reprogramming in DR without duplication of NR values. In a second approach to interactions which suppress pattern duplication, both nasal and temporal one-third-sized eye fragments form approximate “NN” or “TT” duplicate pattern maps, respectively, when either is allowed to round up and form a whole eye. Allowing nasal and temporal thirds to permanently fuse (after removal of a one-third-sized vertical center strip of retina at stage 32) produces a normal projection; allowing the nasal and temporal thirds to interact (fuse) for 35–40 hr, followed by removal of one or the other third, suppresses pattern duplication (produces normal maps) in the remaining third in a majority of cases. Allowing the thirds to interact for 18–30 hr before removal of the temporal third produces a majority result of partial duplication in the remaining nasal third. Partial duplicates are apparent spatial intermediates with regard to interactions which suppress duplication in either fragment type. 相似文献
98.
Jeffrey B. Krahling Robert Gee Patricia A. Murphy James R. Kirk N.E. Tolbert 《Biochemical and biophysical research communications》1978,82(1):136-141
Oxygen uptake with succinate or palmitoyl-CoA as substrates can be measured in rat liver mitochondria that have been isolated by sucrose density gradient centrifugation providing the fractions are diluted with a 30 mM phosphate buffer rather than with an isotonic medium. Separate assay procedures were used to measure peroxisomal and mitochondrial β-oxidation of palmitoyl-CoA in the fractions of a sucrose gradient used to separate these organelles. A preliminary estimate of the ratio of palmitoyl-CoA oxidation by the mitochondrial fraction relative to the surviving peroxisomes from livers of male rats was 3.2. 相似文献
99.
The distribution pattern of silver-NORs was studied in cells of six-day blastocysts and kidney fibroblasts of the rabbit using
the Ag-AS technique. At metaphase and interphase there was a binomial distribution of the number of stained sites in both
populations but blastocysts had a greater percentage of cells with larger numbers of stained sites. Up to 7 of the 8 chromosomes
known to bear NORs were stained in cells from blastocysts while a maximum of 6 were stained in fibroblasts. A significant
difference was found between the mean numbers of chromosomal NORs per cell in metaphases from blastocysts and fibroblasts,
where they were 4.2 and 3.3 respectively. Similarly, the mean number of NORs in interphase was significantly greater in cells
from blastocysts. The distribution of staining on chromosome pair 13 was related to cell type. Significantly more cells in
blastocysts than fibroblasts showed staining in this chromosome pair. 相似文献
100.
The red marine algae Microcladia borealis, M. californica and M. coulteri produce several unusual halogenated monoterpenes including violacene, plocamene-B, plocamene-C, and plocamane-D. The isolation of these terpenes along with a study of their variation in each Microcladia at different locations are described. 相似文献