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971.
HAROLD St. JOHN F.L.S. 《Biological journal of the Linnean Society. Linnean Society of London》1972,4(4):305-310
Sydney Parkinson, aged 18, was Sir Joseph Banks' private assistant and artist on Captain Cook's first voyage around the world. Parkinson died on the voyage. Among his effects delivered to his brother Stanfield were drawings and notes which the latter published as a journal. Included in it is a chapter on the economic plants of Tahiti, and most of them are given scientific names, some of which were new. In 1941 Fosberg adopted two of them to form names which were new combinations under Artocarpus , and Inocarpus . The writer now indicates that Parkinson's names of 1773 were mononomials, hence invalid, but that in the German edition of 1774, edited by Herr "Z", the names are valid binomials. For the two plants mentioned, the authorship of the combinations is revised. 相似文献
972.
973.
Pulmonary prostacyclin (PGI2) production, arterial perfusion, and ultrastructure were correlated in rats sacrificed from 1 day to 6 months after a single exposure of 25 Gy of gamma rays to the right hemithorax. PGI2 production by the irradiated lung decreased to approximately half the normal value 1 day after irradiation (P less than 0.05), then increased steadily throughout the study. By 6 months postirradiation, the right lung produced two to three times as much PGI2 as did either shielded left lung or sham-irradiated lungs (P less than 0.05). Perfusion scans revealed hyperemia of the right lung from 1 to 14 days after irradiation. From its peak at 14 days postirradiation, however, perfusion of the irradiated lung decreased steadily, then reached a plateau from 3 to 6 months at less than half that in the shielded left lung. Electron micrographs of the right lung revealed perivascular edema from 1 to 30 days after irradiation. The right lung then exhibited changes typical of radiation pneumonitis followed by progressive interstitial fibrosis. Platelet aggregates were not observed at any time. Thus, decreased PGI2 production is an immediate but transient response of the lung to radiation injury. Then from 2 to 6 months after irradiation, the fibrotic, hypoperfused lung produces increasing amounts of the potent vasodilator and antithrombotic agent, PGI2. Pulmonary PGI2 production and arterial perfusion are inversely correlated for at least 6 months after hemithoracic irradiation. 相似文献
974.
975.
976.
977.
978.
979.
Norfloxacin, a recently developed antimicrobial fluoroquinolone, was investigated for DNA-damaging activity in rat liver and kidney. After oral administration of single doses ranging from 1 to 8 mmole/kg, DNA fragmentation was absent in liver and kidney both 2 and 6 h after treatment. However, when administered to pregnant rats, the highest doses produced a detectable amount of DNA damage in fetal tissues. This damage appears to be an aspecific consequence of maternal and fetal toxicity rather than a specific genotoxic effect. 相似文献
980.
Jeffrey P Mower Pascal Touzet Julie S Gummow Lynda F Delph Jeffrey D Palmer 《BMC evolutionary biology》2007,7(1):135