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1.
A G Yersin F W Edens D G Simmons 《Comparative biochemistry and physiology. B, Comparative biochemistry》1990,97(4):755-759
1. Liver tryptophan 2,3-dioxygenase (TPO) activity was depressed significantly by the Bordetella avium infection localized in the trachea of the turkey poult. 2. Tryptophan, given orally, induced a significant increase in TPO activity in both control and infected poults. 3. Hydrocortisone induced TPO activity in the turkey in a dose dependent manner. 相似文献
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Does indocyanine green obey Beer's law? 总被引:2,自引:0,他引:2
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M McEvoy K Porter P Mortimer N Simmons D Shanson 《BMJ (Clinical research ed.)》1987,294(6587):1595-1597
In a prospective study of 150 health care workers in the United Kingdom who had been accidentally exposed to the human immunodeficiency virus no evidence of transmission was found. Larger studies in the United States and anecdotal accounts in publications from other countries confirm that the risk of occupational infection is very low. Health care workers must adopt safe procedures at all times, however, to avoid exposure to infection. 相似文献
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Wendy A. Douglass Robert H. Hyland Christopher D. Buckley Aymen Al-Shamkhani Jacqueline M. Shaw Sarah L. Scarth David L. Simmons S.K.Alex Law 《FEBS letters》1998,440(3):125
The cysteine-rich region (CRR) of the β2 integrin subunit was replaced by that of β1 to give the chimera β2NV1. β2NV1 can combine with αL to form a variant leukocyte-function-associated antigen (LFA)-1 on COS cell surface, suggesting that the specificity of the β2 interaction with αL does not lie in the CRR. Unlike those expressing wild-type LFA-1, COS cells expressing αLβ2NV1 are constitutively active in intercellular adhesion molecule (ICAM)-1 adhesion. These results suggest that activation of LFA-1 involves the release of an intramolecular constraint, which is maintained, in part, by the authentic β2 CRR. 相似文献
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H. Simmons 《BMJ (Clinical research ed.)》1949,1(4609):808-809
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Neurohypophyseal peptide hormone activity is present in the pineal gland of mammals, and varies over a seasonal cycle. Pineal peptide levels, measured by arginine vasotocin (AVT) radioimmunoassay, increase dramatically for a brief time during August each year. The manner in which this cycle is regulated is as yet unknown. Input to the pineal from sympathetic axons arising in the superior cervical ganglia (SCG) is essential for the generation and regulation of the circadian rhythm in melatonin synthesis, and is the only pathway known to regulate pineal biochemical processes. It was of interest then to determine the impact of the SCG on the seasonal peptide cycle. Levels of pineal arginine vasotocin immunoactivity (iAVT) were monitored during August, 1984, in rats which had been superior cervical ganglionectomized (SCGX), in sham-operated and intact controls (L:D 12:12), and in rats subjected to L:D 22:2. The results indicate that SCGX does not abolish the seasonal cycle, but may influence the timing of the iAVT peak. Inhibition of pineal melatonin synthesis by exposure of rats to L:D 22:2 did not mimic the phase delay seen with SCGX, but did cause a significant increase in the amplitude of the August iAVT activity peak. 相似文献
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