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At least 1,639 records · Page 91Linked to original sources
PubMed1977

[Trial preparation and evaluation of a 81mKr-generator for medical use].

A prototype 81mKr-generator consisting of an ion exchange column and some attachments for handling was prepared on trial. Parent nuclide 81Rb obtained by the reaction of 82Kr(p, 2n)81Rb was absorbed on the resin, and radionuclidic purity, sterility and apyrogenicity of the generator eluate were examined. Analysis of gamma-ray spectrum obtained with a Ge(Li) detector and a multichannel pulse height analyzer revealed that the nuclidic purity of the 81mKr in the eluate was 99.997-99.999% with 0.001-0.003% of 79Kr at the start of the elution. Sterility and apyrogenicity of the eluate were proved by J.P. sterility test and limulus test respectively. All results obtained show that the 81mKr-generator is very suitable for medical application.

Evaluation Studies as Topic↗
PubMed1978

[An evaluation of inhalation and perfusion scintigraphy with 81mKr (author's transl)].

As 81mKr is a radioactive noble gas which has a very short half-life of 13 seconds, it leads no environmental contamination in a laboratory room. Because of its low radiation dose in the human body, it had many merits in routine tests of the inhalation and perfusion scintigraphy, which were very useful extremely in infants, old men and severe patients in need of cooperation. The studies with 81mKr were, either, useful as a load test, since these could repeatedly readily, evaluate the ventilation and perfusion dynamics before and after administration of drugs and show the distribution of the ventilation and perfusion correspond to the various lung volume level.

Aged↗
PubMed1982

Convenient 77Kr production method for medical use.

A convenient method of 77Kr production has been developed for its routine medical use in cerebral blood flow measurement. An aqueous solution of NaBr (40 wt%) was used as the target and 77Kr produced by the 79Br(p, 3n)77Kr reaction was rapidly recovered from the target under a He stream. The optimal target thickness was determined to be 5 approximately 6 mm by investigating radionuclidic purity and proton current effect on the yield. About 740 MBq (20 mCi) of 77Kr with a radionuclidic purity of 92% was obtained within 5 min after a 5 microA-20 min irradiation. The present method has been demonstrated to be suitable for routine 77Kr production.

Cerebrovascular Circulation↗
PubMed1984

Removal of dissolved 85Kr by vacuum degassing method.

In the irradiation apparatus where unsealed 85Kr gas is used as an internal radiation source for liquid-phase chemical reaction, the 85Kr gas dissolved in a liquid reactant must be removed after irradiation. Experiments on removal of dissolved 85Kr by the vacuum degassing method were carried out to examine the influence of degassing temperature, initial 85Kr concentration and stirring of a solution on the removal. The liquid reactant used was a water of 500 ml in which 85Kr gas was dissolved. The removal effect became greater with increasing temperature. The dissolved 85Kr concentration after removal decreased exponentially with the reciprocal of degassing temperature. Further, the removal effect was intensely affected by stirring of the solution and was independent of the initial 85Kr concentration. The removal factor of dissolved 85Kr at 33 degrees C reached 5 X 10(3) after a 30 minute lapse.

Gases↗
PubMed1987

[Determination of residual activities in 99mTc generators and 81mKr generators].

The residual activities present in spent 99Mo-99mTc generators and 81Rb-81mKr generators were determined from a view point of the disposal of radiopharmaceuticals. The results showed that seven kinds of residual nuclides such as 95Zr-95Nb, 103Ru, 90Sr, etc. were found in 99mTc generators with maximum level of 740 Bq/3.7 GBq (0.02 muCi/100 mCi) at one year after the reference date. In 81mKr generators one year old, six nuclides such as 57Co, 83Rb, 84Rb and others remained and these activities were less than 3.7 kBq/370 MBq (0.1 muCi/10 mCi). On the basis of these data, the disposal of 99mTc generators and 81mKr generators is discussed.

Humans↗