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31.
Phillip A. Reece Irene Cozamanis Rudolf Zacest 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1980,181(3-4)
Selective high-performance liquid chromatographic assays for hydralazine (I), hydralazine pyruvic acid hydrazone (II) and the acetylation metabolites, namely s-triazolo[3,4-a]-phthalazine (V) and 3-hydroxymethyl (VI) and 3-methyl-s-triazolo[3,4-a]phthalazine (VII) in human plasma were developed. Utilizing the fluorescence of these compounds or their derivatives the limits of detection could be extended down to 5 nmole/l (1 ng/ml) for I, 1 nmole/l (0.2 ng/ml) for II and 0.5 nmole/l (0.1 ng/ml) for V–VII. The intra-assay coefficients of variation for the assays ranged from 2 to 7% over the concentration range 5.0 to 0.05 μmole/l and the inter-assay variability in the slope of the standard curves ranged from 4 to 8%. An improved method for measuring the sum of I plus all its hydrazones (apparent I) was also developed. On addition of I to fresh plasma at 37°, half the added I was converted to II within 15 min and there was no detectable level of I, 2 h after the addition. The plasma level—time course of I, and its metabolites in a healthy volunteer (slow acetylator) following separate oral and intravenous administrations of I indicated that I contributed only a small fraction (4.3 and 4.7% respectively) to the area under the plasma level—time curve of apparent hydralazine. 相似文献
32.
By use of a relatively new mixed stationary phase, complete separation of the branched-chain α-keto acids as O-trimethylsilyl-quinoxalinol derivatives is achieved within 10 min by packed column gas chromatography. Precise quantification of less than 5 nmol of α-keto acids in biological samples is possible. In small aqueous samples the α-keto acids are directly derivatized without prior purification. Plasma need only be deproteinized by perchlorate and neutralized before derivatization. Average relative precision for determination of the three main branched-chain α-keto acids is ± 5.8%. 相似文献
33.
An epoxy-hydroxy compound, 10-hydroxy-11,12-epoxy-eicosa-5,8,14-trienoic acid, has been identified as a product on incubation of arachidonic acid with washed blood platelets from human, horse, cat, dog and rabbit. Gas chromatographic - mass spectrometric (GC-MS) evidence of structure is discussed. 相似文献
34.
William T. Keeton A. Irene Brown 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1976,105(3):259-266
Summary In a second attempt to repeat recently published experiments that appear to support an hypothesis that olfactory cues play an important role in pigeon navigation, we have conducted 15 experiments in which-pinene in vaseline was applied to the birds' beak and nostrils prior to release, a procedure reported by Benvenutiet al. (1973) to cause a decrement in homing performance. Our results show no consistent difference between the experimental and control birds in any of the three parameters (initial orientation, rapidity of orientation, homing speed) measured by Benvenutiet al.
We thank our colleagues Timothy Larkin, Marilyn Yodlowski, and Lindsay Goodloe for their help in conducting the releases. This research was supported by Grant BMS 72-02198-AO2 from the National Science Foundation. 相似文献
35.
Nerve terminal regions in walking leg opener muscles of several crayfish of different ages (0 to 245 days after hatching) were examined by means of electron microscopy. This muscle is innervated by two axons (excitatory and inhibitory) and at maturity contains three classes of synapse: excitatory and inhibitory neuromuscular synapses, and inhibitory axo-axonal synapses. The muscle itself is initially a syncytium, which gradually becomes subdivided into distinct “muscle fibers” as the animal matures. Innervation was not found in the opener muscle just before or just after hatching, but was present in restricted locations on the inner side of the muscle within a few days of hatching. As the muscle enlarged and became subdivided, innervation appeared in various other locations. Synaptic contacts were located in young stages soon after hatching, and in later stages. Morphological differences characteristic of excitatory and inhibitory nerve terminals could be found even at the earliest stages of innervation. Both excitatory and inhibitory synapses, but particularly the former, showed evidence of progressive enlargement to a final size within the first two months, and no evidence for further enlargement of existing synapses thereafter. Synaptic maturation also involved the appearance of presynaptic “dense bodies” thought to be regions at which transmitter substance is preferentially released. Nerve terminals at different levels of maturation were observed in opener muscles of young crayfish. Clear evidence for differential maturation of the three types of synapse present in this muscle was obtained. The inhibitory neuromuscular synapses attained their final average size and developed their dense bodies sooner than the excitatory neuromuscular synapses. The inhibitory axo-axonal synapses were the last to appear and to mature. 相似文献
36.
37.
Transcriptome profiling of immune tissues reveals habitat‐specific gene expression between lake and river sticklebacks 下载免费PDF全文
38.
Ching T. Hou Ramesh Patel Allen I. Laskin Nancy Barnabe Irene Barist 《Applied microbiology》1983,46(1):171-177
Sixteen new cultures of propane-utilizing bacteria were isolated from lake water from Warinanco Park, Linden, N.J. and from lake and soil samples from Bayway Refinery, Linden, N.J. In addition, 19 known cultures obtained from culture collections were also found to be able to grow on propane as the sole carbon and energy source. In addition to their ability to oxidize n-alkanes, resting-cell suspensions of both new cultures and known cultures grown on propane oxidize short-chain alkenes to their corresponding 1,2-epoxides. Among the substrate alkenes, propylene was oxidized at the highest rate. In contrast to the case with methylotrophic bacteria, the product epoxides are further metabolized. Propane and other gaseous n-alkanes inhibit the epoxidation of propylene. The optimum conditions for in vivo epoxidation are described. Results from inhibition studies indicate that a propane monooxygenase system catalyzes both the epoxidation and hydroxylation reactions. Experiments with cell-free extracts show that both hydroxylation and epoxidation activities are located in the soluble fraction obtained after 80,000 × g centrifugation. 相似文献
39.
40.
Lackner A Genta K Koppensteiner H Herbacek I Holzmann K Spiegl-Kreinecker S Berger W Grusch M 《Analytical biochemistry》2008,380(1):146-148
Baculoviruses are widely used for protein production in insect cells, and their potential for gene transfer to mammalian cells is increasingly being recognized. Here we describe a baculovirus vector with a bicistronic mammalian expression cassette and demonstrate its suitability for efficient transient and stable protein expression in human glioblastoma cells. Bicistronic baculovirus vectors are safe, cost efficient, and easy to produce; thus, they represent an excellent gene transfer system for mammalian cells. 相似文献