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81.
Localization of the c-ab1 oncogene adjacent to a translocation break point in chronic myelocytic leukaemia 总被引:67,自引:0,他引:67
N Heisterkamp J R Stephenson J Groffen P F Hansen A de Klein C R Bartram G Grosveld 《Nature》1983,306(5940):239-242
The human c-ab1 oncogene maps within the region (q34-qter) of chromosome 9 which is translocated to chromosome 22, the Philadelphia (Ph') chromosome, in chronic myelocytic leukaemia (CML). The position of the Ph' chromosomal break point is shown to be variable and, in one CML patient, has been localized immediately 5' of, or within, the c-ab1 oncogene. A DNA restriction fragment corresponding to this site has been molecularly cloned and shown to represent a chimaeric fragment of DNA from chromosomes 9 and 22. 相似文献
82.
83.
Folic acid levels in blood and seminal plasma of normo- and oligospermic patients prior and following folic acid treatment 总被引:2,自引:0,他引:2
Folic acid was estimated in blood and seminal plasma of normo- and oligospermic men. Following folic acid administration (10 mg TID for 30 days), the levels in blood and semen increased. However, sperm counts, motility and DNA content of spermatozoa were not affected. 相似文献
84.
85.
B. Landau R. Singer T. Klein E. Segenreich 《Cellular and molecular life sciences : CMLS》1978,34(10):1301-1302
Summary Folic acid was estimated in blood and seminal plasma of normo- and oligospermic men. Following folic acid administration (10 mg TID for 30 days), the levels in blood and semen increased. However, sperm counts, motility and DNA content of spermatozoa were not affected. 相似文献
86.
87.
An 'incipient' spreading centre east of (and orthogonal to) the East Pacific Rise at 2 degrees 40' N has been identified as forming a portion of the northern boundary of the Galapagos microplate. This spreading centre was described as a slowly diverging, westward propagating rift, tapering towards the East Pacific Rise. Here we present evidence that the 'incipient rift' has also rifted towards the east and opens anticlockwise about a pivot at its eastern end. The 'incipient rift' then bounds a second microplate, north of the clockwise-rotating Galapagos microplate. The Galapagos triple junction region, in the eastern equatorial Pacific Ocean, thus consists of two counter-rotating microplates partly separated by the Hess Deep rift. Our kinematic solution for microplate motion relative to the major plates indicates that the two counter-rotating microplates may be treated as rigid blocks driven by drag on the microplates' edges3. 相似文献
88.
L. R. Klein 《Journal of forecasting》1984,3(1):1-9
Careful forecasts, as accurate as possible, are central to the successful implementation of policy. There are fundamental reasons why policy makers cannot ‘play by ear’, adjusting policy quickly to each unexpected deviation in economic outcomes. Specific incidents are described where economic policy went awry because of faulty forecasts. The policy process is described in detail to show precisely where the forecast enters. Forecasting as a validation tool for establishing credibility in policy formation is analysed and discussed. Some estimated measure of forecast accuracy is presented, together with commentary on the necessary degrees of precision for successful implementation of policy. 相似文献
89.
C. E. Steele J. D. Plenefisch N. W. Klein 《Cellular and molecular life sciences : CMLS》1982,38(10):1237-1239
Summary Human and rat sera were assayed for teratogenic activity using a whole rat embryo culture technique. Sera prepared from blood withdrawn 1–5 h after the ingestion of vitamin A capsules caused developmental retardation and craniofacial abnormalities. Control sera permitted normal growth and differentiation.Financial support for this project was provided by Department of Energy contract EVO 3139 (Office of Health and Environmental Research), USA (Scientific contribution 940, Storrs Agricultural Experiment Station), and by the Medical Research Council, U.K. 相似文献