17,472 research outputs found
Long-term stability test of a triple GEM detector
The main aim of the study is to perform the long-term stability test of gain
of the single mask triple GEM detector. A simple method is used for this long-
term stability test using a radioactive X-ray source with high activity. The
test is continued till accumulation of charge per unit area > 12.0 mC/mm2. The
details of the chamber fabrication, the test set-up, the method of measurement
and the test results are presented in this paper.Comment: 8 pages, 5 figure
Modulation of testicular lutropin receptors in the developing male rat
In the developing male rat around 40 days of age, the testis appears to contain the maximum amount of lutropin receptors per unit weight. During this period, circulating levels of testosterone markedly increase without the concomitant major surges in lutropin levels. The increased sensitivity and responsiveness of tests to basal levels of circulating lutropin during this period is accompanied by enhanced serum prolactin levels suggesting that this hormone may be involved in this process. The finding that prolactin treatment of pubertal rats for 3 days induced the formation of more testicular lutropin receptors supports the above premise. However, shortterm immunoneutralisation of endogenous prolactin did not significantly alter the specific binding of [125I]-labelled lutropin to testicular membranes. Interestingly, during development, a close correction exists between receptor occupancy and capacity of the tissue to bind labelled lutropin. The apparent dissociation between serum lutropin levels, on the one hand and tissue occupancy and free receptor contents on the other, suggests that factors other than lutropin (presumably prolactin) are involved in the modulation of the sensitivity and the responsiveness of the testis to lutropin during early development
Isolation of sheep anterior pituitary messenger RNA and its translation in a heterologous cell-free system
A preparation rich in the specific messenger RNA involved in the synthesis of prolactin from sheep anterior pituitary glands was obtained by employing both the immunochemical and affinity techniques. A dose-dependent and efficient stimulation of protein synthesis by the isolated total pituitary RNA as well as poly (A) rich RNA were achieved with the reticulocyte system. The synthesis of prolactin as one of the translational products of this cell-free system was established by specific immunoprecipitation followed by resolution on sodium dodecyl sulphate polyacrylamide gel electrophoresis
- …