Radioimmunoassay of thyrotropin (TSH) is well-established, and highly sensitive radioimmunometric assay is often used clinically (1). Some recent results indicate that TSH immunoreactivity and bioactivity are not always synonymous (2). The detection limit of present bioassays for bovine TSH is about 0.5-1 milli-int. unit/L (3-6). More-sensitive bioassay is necessary for evaluating human TSH. Th...

L IVER transplantation has been increasingly used to treat end-stage liver diseases since the introduction of Cy A in combination with other immunosuppressive agents. 1 Although Cy A has a powerful immunosuppressive effect on allograft rejection, many transplant recipients still experience rejection episodes that are often irreversible. The nephrotoxicity of Cy A in some recipients has necessit...

A radial diffusion bioassay for miconazole, which employs Candida stellatoidea as the indicator organism, is described. Results from three patients treated with the drug are presented.

The usually accepted mothods for bioassay of histamine according to Schild el at. (1951), employ (i) eat's blood pressure, (ii) guinea pig's uterus or (iii) the guinea pig's ileum. Code (1952) has reported that the most convenient tissue for the bioassay of histamine is guinea pig's terminal portion of the ileum and on this account it is the most widely employed pharmacological preparation for ...

An in vitro bioassay for cholecystokinin which is superior to the previously described in vivo assays has been properly validated mathematically. The specificity of the assay has been assessed by measuring the potency of other polypeptides which share the same C-terminal pentapeptide sequence with cholecystokinin (gastrin, caerulin, octapeptide of cholecystokinin, and pentagastrin). The assay i...

Estimation of unknown pesticide levels in experimental samples is an important aspect of many agricultural and environmental studies. Such measurements are often made utilizing a “standard” dose response curve. This methodology compares the biological response of a target organism at known dosages to the response of the same organism exposed to an unknown sample. These “bioassays” are typically...

Rhopalosiphum padi L. causes significant damage to winter wheat (Triticum aestivum L.), even without obvious aboveground symptoms of injury. Our objectives were to develop a juvenile-plant bioassay for bird cherry-oat aphid (BCOA) resistance that allows rapid phenotypic differentiation. Central features of the bioassay include root and shoot weight measurements of 3-week-old seedlings produced ...

The linear correlation between the EC50 values of 50 substances obtained in luminescence bioassays using Vibrio fischeri and Vibrio harveyi and in a fluorogenic bioassay using Escherichia coli was investigated. As a result, a significant correlation was found between the said values in all three toxicity tests. The bioassay using V. harveyi had a sensitivity similar to that of the fluorogenic b...

A wind tunnel bioassay system to screen mosquito repellents is described. A wind tunnel is utilized to exploit the upwind flight response of host-seeking mosquitoes. Mosquitoes within the wind tunnel are activated with human breath, fly upwind, and land on heated chick skins. This behavioral sequence results in a consistently high percentage of the test population approaching repellent or contr...