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C Hsiao

Publications and source records attributed to C Hsiao.

10 recordsLinked to original sources
PubMed1989

Peripheral and central dopamine receptors in respiratory control.

The role of peripheral and central dopaminergic mechanisms in respiratory control was studied in anesthetized cats. In one series, we simultaneously measured carotid chemoreceptor and ventilatory responses to hypoxia and hypercapnia before and after a saturation dose of intravenous domperidone, a peripheral dopamine (D2) receptor antagonist. Both carotid chemoreceptor and ventilatory responses were augmented by domperidone essentially in proportion, suggesting that they reflected the increase of peripheral chemoreceptor activity. Haloperidol which crosses into the brain from blood, given subsequent to domperidone, did not further affect carotid chemoreceptor responses but attenuated ventilatory responses to hypoxia without significantly altering those to hypercapnia. Thus, the additional ventilatory effect of haloperidol is mediated through central dopaminergic mechanisms involving peripheral chemoreflex pathway alone. In another series, the anesthetized cats were paralyzed and artificially ventilated to study carotid chemoreceptor responses to step increases in the end-tidal PCO2 before and after domperidone. Domperidone significantly augmented the responses to CO2. The results support the hypothesis that both peripheral and central dopaminergic mechanisms play a significant modulatory role in chemoreflex respiratory control.

Animals↗
PubMed1989

Meiotic multivalent orientation and cell developmental delay.

In the heterozygote for the combination of an interchange (662W;3R/6R) and a Robertsonian split (3R) of rye, one type of adjacent orientation leads to trisomy in the progeny. Pollen mother cells with adjacent orientation of the translocation quinquivalent or with a trivalent and a bivalent were delayed in their development and appeared at prometaphase and metaphase later than cells with alternate quinquivalents. Delay in cell development is ascribed to unfavorable (early) prophase positioning of chromosomes.

Anaphase↗
PubMed1987

A multiple-dose pharmacokinetic comparison of naproxen as a once-daily controlled-release tablet and a twice-daily conventional tablet.

The bioequivalence and absorption kinetics of naproxen in a new controlled-release tablet (750 mg or 1,000 mg naproxen) administered once daily were determined relative to an equivalent dose of the conventional naproxen tablet (375 mg or 500 mg naproxen) administered q12h. Naproxen was well absorbed from the controlled-release tablet (about 90%) compared with the conventional tablet. Absorption was dependent on drug release from the tablet matrix. The mean absorption time of naproxen averaged 8.4 hours for the 750-mg controlled-release tablet and 9.2 hours for the 1,000-mg controlled-release tablet. Once-daily administration of the controlled-release tablet resulted in equivalent trough concentrations of naproxen, and steady-state plasma concentrations were maintained within narrower limits than with twice-daily naproxen.

Adult↗