We present the distribution of astronomical papers published by Chinese authors in 1986–1990 across the various subfields of astronomy, the total number of papers produced by each observatory or university during the five years, and the ranking of the observatories by productivity. Our main data base includes 24 journals: 9 foreign ones published in English, 10 Chinese national ones, and 5 Chinese observatory publications. About 70 journals published by Chinese universities have also been consulted. This data base covers up to 90% of all astronomical papers published during this period.
In order to develop small molecular probes for imaging of Aβ plaques in the brain with Alzheimer’s disease, four benzothiazole derivatives as Aβ probes, 3’-125I-BTA, 3’-125I-CBTA, 3’-125I-BTA-Ac, and 3’-125I-CBTA-Ac were successfully prepared. The four probes displayed the following initial brain uptake: 10.28 %ID/g, 3.62 %ID/g, 3.33 %ID/g and 3.71 %ID/g at 2-minute post iv injection, respectively. The study of quantitative structure-activity relationship (QSAR) indicated that the initial brain uptake was correlated with molecule volume (Vm) and dipole moment (Dp), but the Dp was the main factor. 3’-125I-BTA has the highest initial brain uptake among the four Aβ probes because of the smallest Dp.
Authors:Zhang Jinming, Tian Jiahe, Wang Wushang, and Liu Baoli
[11C]-choline has been reported as a potential tracer for imaging a variety of human tumors with positron emission tomography
(PET). A new labeling technique for [11C]-choline was established depending on parameters optimized, such as reaction time, volume, temperature, and the quantity
of DMAE.The synthesis yield was improved from 82.0% to 96.5% (EOB), while the consumption of DMAE precursor decreased from
60 to 2 mg. Absolute yield of [11C]-choline was 2500 MBq for a 10-minute irradiation at15mA, and a total synthesis time of less than 8 minutes from [11C]-CH3I to [11C]-choline.
To investigate the radio impurity in the radiolysis of 18F-FDG at high radiodose and radioconcentrated solutions and develop methods of repurification. The radiolysis of 18F-FDG was analyzed by TLC. The radio-impurity was confirmed by biodistribution and small animal PET/CT studies. 18F-FDG was unstable at high radioconcentrition over 37 GBq/mL or under basic condition. TLC, biodistribution and PET/CT all
indicated that the main autoradiolysis byproduct was free fluoride ion. The radiolyzed 18F-FDG was repurified by solid-phase extraction (SPE) column. The repurified 18F-FDG had a radiochemical purity (RCP) of over 99% and significantly lower bone uptake than that was before repurification
(P = 0.0003). There was a positive correlation between the recovery yield and the purity of 18F-FDG (R2 = 0.66).