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41.
Distribution of membrane cholesterol of adrenal cortical cells after corticotropin stimulation. 总被引:1,自引:0,他引:1
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Membrane cholesterol in adrenal cortical cells is enriched in the plasma membrane. Stimulation of isolated adrenal cortical cells with corticotropin leads to the production of corticosterone. At high levels of corticotropin, cholesterol for corticosterone synthesis arises by hydrolysis of cellular cholesteryl ester, whereas at lower levels of corticotropin cholesteryl ester levels are unchanged from control values and there is a decrease in plasma-membrane cholesterol levels. 相似文献
42.
Arthur E. Greene Jesse Charney Warren W. Nichols Lewis L. Coriell 《In vitro cellular & developmental biology. Plant》1972,7(6):313-322
Summary Three mosquito cell cultures designated as Suitor's clone ofAedes aegypti, Culiseta inornata andAedes vexans were shown to be moth by immunological, karyological, and isozyme analyses. The cells reacted with rabbit antimoth serum
but not rabbit antimosquito serum. Chromosome analyses indicated Lepidopteran rather than Dipteran morphology, and three isozyme
systems were confirmative. Any one of these assays would be sufficient to indicate that contamination had occurred and could
be used as a periodic check for identity of cell cultures. Morphology and growth characteristics are also valid criteria to
distinguish between these particular orders of insect cells.
These studies were supported by Grant CA-04953-12 from the National Cancer Institute; General Research Support Grant FR-5582
from the National Institues of Health; and Grant-in-Aid Contract M-43 from the State of New Jersey.
Recipient of Research Career Award 5-K3-16,749. from the National Institutes of Health. 相似文献
43.
Arthur E. Greene Jesse Charney Warren W. Nichols Lewis L. Coriell 《In vitro cellular & developmental biology. Plant》1972,7(5):313-322
Summary Three mosquito cell cultures designated as Suitor's clone ofAedes aegypti, Culiseta inornata, andAedes vexans were shown to be moth by immunological, karyological, and isozyme analyses. The cells reacted with rabbit antimoth serum
but not rabbit antimosquito serum. Chromosome analyses indicated Lepidopteran rather than Dipteran morphology, and three isozyme
systems were confirmative. Any one of these assays would be sufficient to indicate that contamination had occurred and could
be used as a periodic check for identity of cell cultures. Morphology and growth characteristics are also valid criteria to
distinguish between these particular orders of insect cells.
These studies were supported by Grant CA-04953-12 from the National Cancer Institute; General Research Support Grant FR-5582
from the National Institutes of Health; and Grant-in-Aid Contract M-43 from the State of New Jersey.
Recipient of Research Career Award 5-K3-16,749 from the National Institutes of Health. 相似文献
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Procedures are described for phosphorylating protected nucleotides, oligonucleotides and phosphoramidate oligonucleotide derivatives at the 3′-hydroxyl group. The conditions (phosphorylation with phosphorus oxychloride and pyridine in dioxane followed by hydrolysis with aqueous pyridine) are sufficiently mild that base labile (trifluoroacetylamino; β-cyanoethyl phosphotriester) and acid labile (O-monomethoxytrityl; phosphoramidate) functions are retained intact. Application of the technique is illustrated by the synthesis of dpT, dTp, d(CF3CONH)Tp, dTpNTp, and dTpNTpNTp. In addition, the utilization of phosphorus oxychloride in joining thymidine derivatives and dinucleoside phosphotriester blocks via phosphodiester links is described. 相似文献
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48.
Endogenous gibberellins of a radiation induced single gene dwarf mutant of bean 总被引:2,自引:2,他引:0
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The distribution of endogenous gibberellins in Dwarf-1, a single gene dwarf mutant of Mexico 80-R red beans, was studied. Parallel extraction and fractionation of seeds of this mutant and those of a normal homozygous line followed by thin layer chromatography and bioassays using Rumex obtusifolius, wheat seed endosperm and dwarf bean plants revealed that a stem elongation control factor was contained in the non-acidic fraction from normal, but not from Dwarf-1, seeds. It was concluded that the single gene mutation causes a block either in gibberellin precursor formation or in production of a non-acidic fraction gibberellin-like substance. 相似文献
49.
The enzymatic synthesis of wax in liver 总被引:2,自引:0,他引:2
50.
The levels of airborne contamination in various areas of two hospitals were determined during a 15-month sampling period, using Casella and Andersen volumetric samplers. Based on nearly 5,000 samples, the mean count per ft3 ranged from 4.5 in obstetric-gynecology delivery rooms to 72.4 in waste-handling areas. The mean count for the entire hospital environment was on the order of 20 contaminants per ft3; 48% were associated with particles >5 μ diam, 30% with particles between 2 and 6 μ diam, and 22% with particles <2 μ diam. The airborne contamination was influenced by traffic, activity, ventilation considerations, and gross surface contamination, but not markedly by seasonal changes. When suitable control measures were implemented, the level of contamination could be diminished and kept low. 相似文献