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31.
Thirty-nine previously unpublished reports of the endangered black-footed ferret from Wyoming are listed with dates, locations, number of animals, sources, and comments. 相似文献
32.
Stephen L. Clark 《西北部美国博物学家》2011,35(4)
Field and herbarium studies of Penstemon cyananthus Hook. ssp. longiflorus Pennell suggest that this taxon be elevated to species rank. 相似文献
33.
Allen Clark Dotson 《Studies in History and Philosophy of Science Part B: Studies in History and Philosophy of Modern Physics》2012,43(1):64-68
Karl Popper and Herbert Dingle engaged in a fascinating debate concerning the kind of theory the special theory of relativity is. One of the issues was whether applications of the theory could be made consistent with the principle of relativity, a cornerstone of the theory itself. The principle of relativity seems to imply some sort of symmetry in results obtained for similar experiments as observed in two different inertial reference frames. Peter Hayes has recently dealt with the Dingle–Popper debate on this matter, as well as other issues. The present paper seeks to clarify what kind of symmetry is appropriate in a situation discussed by Popper, Dingle, and Hayes. 相似文献
34.
35.
WANGYi GlarkAlan WANGJiaxun SUNMenghong SHIDaren 《科学通报(英文版)》2004,49(1):3-38
Functional deficiency of mismatch repair (MMR) system is one of the mechanisms of tumorigenesis. With the development of the investigation and the requirement from the clinical diagnosis and treatment it is necessary to build up a method to evaluate the functional status of the whole MMR system in the concerned tumors. The original ssDNA and dsDNA from wild type (wt) bacteriophage M13mp2 and its three derivates with mutation points in the 相似文献
36.
Summary ß-(p-hydroxyphenyl)ethanol is present in the chest gland secretion of the galago Galago crassicaudatus. 相似文献
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38.
Ribonucleotide reductase is an essential enzyme for DNA synthesis in all prokaryotic and eukaryotic cells; it catalyses the reductive conversion of ribonucleotides to deoxyribonucleotides. Several herpesviruses including herpes simplex virus type 1 (HSV-1), HSV-2, pseudorabies virus (PRV), equine herpesvirus type 1 (EHV-1) and Epstein-Barr virus (EBV) have been found to induce novel ribonucleotide reductase activities. There is evidence that the HSV-1 ribonucleotide reductase activity is virus-encoded and essential for virus replication. This makes herpesvirus ribonucleotide reductases potential targets for antiviral chemotherapy. The HSV-1-encoded enzyme consists of two subunits: V136, the large subunit of relative molecular mass (Mr) 136,000 (136K) (RR1), which has been shown to be essential for enzyme activity, and V38, the small subunit (RR2) which forms a complex with the large subunit and is also likely to be essential for enzyme activity. Two particular features of the enzyme make it an attractive antiviral target. First, there is evidence for a common, highly conserved herpesvirus ribonucleotide reductase and second, the interaction between the large and small subunits may itself be exploitable. Here we identify a synthetic peptide which specifically inhibits the activity of virus-induced enzyme. We deduce that the mechanism of inhibition involves interference with the normal interaction between the two types of subunit. 相似文献
39.
A GTP requirement for binding initiator tRNA to ribosomes 总被引:14,自引:0,他引:14
40.
M. M. Cohen Ch. C. Huang H. F. Clark 《Cellular and molecular life sciences : CMLS》1967,23(9):769-771
Zusammenfassung Die somatischen Chromosomen der 3 EidechsenartenGekko gecko (2N=38),Iguana iguana (2N=34) undCrotophytus collaris (2N=36), werden dargestellt.G. gecko besitzt metazentrische, subteleozentrische und teleozentrische Elemente, aber keine Mikrochromosomen.I. iguana undC. collaris besitzen Makrochromosomen (6 Paare) und Mikrochromosomen. Bei den ArtenG. gecko undI. iguana waren in keinen von beiden Geschlechtern heteromorphische Chromosomenpaare nach zuweisen.
Supported by Project No. 417 from the U.S. Children's Bureau and Grant No. 08737 from the National Cancer Institute. 相似文献
Supported by Project No. 417 from the U.S. Children's Bureau and Grant No. 08737 from the National Cancer Institute. 相似文献