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981.
This article explains the breast physiology and epidemiologic criteria supporting the abortion breast cancer link and the sociologic factors that cause this risk to remain largely unknown to both medical professionals and the public. Abortion increases breast cancer risk through multiple mechanisms. Pregnancy exposes women to high levels of estrogen acting as a mitogen and genotoxin, and induced abortion then leaves their breasts with more places for cancers to start. They have a higher risk of subsequent premature deliveries that further increase their risks of breast cancer. Rampant breast cancer seen in ever younger women will not allow this issue to be suppressed.  相似文献   
982.
Matthew J. Butler Department of Economics, 549 Evans Hall, University of California, Berkeley, CA 94720 e-mail: butler{at}econ.berkeley.edu e-mail: daniel_butler{at}stanford.edu (corresponding author) We provide an introduction to the regression discontinuity design(RDD) and use the technique to evaluate models of sequentialSenate elections predicting that the winning party for one Senateseat will receive fewer votes in the next election for the otherseat. Using data on U.S. Senate elections from 1946 to 2004,we find strong evidence that the outcomes of the elections forthe two Senate seats are independent.  相似文献   
983.
The allele frequencies for the 15 short tandem repeats included in the Power Plex-16 kit (Promega Corp., Madison, WI, USA) were determined in a sample of 429 unrelated individuals from five provinces of the Northern and Northeastern regions of Argentina. Three Northern provinces including Salta, Formosa and Chaco and two within the region surrounded by the Paraná and Uruguay Rivers commonly known as the Argentine Mesopotamia, including Misiones and Corrientes. Since in this region Entre Ríos Province is also present, previously published results were used for comparison. The calculated parameters: polymorphism information content (PIC); discrimination power (DP); matching probability (MP); typical paternity index (TPI) and power of exclusion (PE) showed Penta E to be the most valuable marker from the studied sample set. All loci met Hardy-Weinberg expectations using the Bonferroni correction for the number of loci analyzed, except D3S1358 in Salta and THO1 in Formosa provinces. Population differentiation test revealed that the Salta population sample data denoted significant differences for various loci when compared with the other province information presented here in, as well as with other published data sets.  相似文献   
984.
McGinn D 《Newsweek》2006,148(14):43
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986.
Although seat belts significantly reduce the extent and severity of injuries sustained by motor vehicle occupants, seat belts are known to be associated with chest and abdominal trauma. Less commonly understood are severe neck injuries caused by the use of two-point automatic shoulder harnesses without concurrent use of a manual lap belt. Such injuries may include cervical spine fractures, craniocervical dislocations and rarely decapitation. Recognizing patterned injuries caused by seat belts and the ability to correlate autopsy findings with the circumstances surrounding the death will allow for correct interpretation of seat-belt related trauma. The four cases described detail fatal neck injuries as a result of improper seat belt use in which an automatic two-point shoulder harness was used without a manual lap restraint. In two of the cases, the victims were decapitated.  相似文献   
987.
Use of proximal femur shape to determine ancestry has appeal, but its validity is problematic because of unaddressed issues associated with skeletal plasticity, within- and between-population variation, sample selection, and interobserver error. In this paper, I inspect within- and between-group variation in proximal femur shape using five groups (American Blacks, American Whites, Hispanics, Native Americans, and Polynesians), and examine the affect of three environmental variables (subsistence strategy, physical terrain, and geographical region). Finally. I consider the validity of using the proximal femur to assess ancestry. The results show that there is significant within-group variation in proximal femur shape. Among Native Americans, both geographical location and subsistence strategy have a significant affect on proximal femur shape. Nevertheless, this study generally verifies the assertion that the proximal femur can be used reliably to distinguish Native Americans from American Blacks and Whites, but its precision may be reduced in some geographical regions.  相似文献   
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Reviews     
Roger Manser, Failed Transitions: The Eastern European Economy and Environment since the Fall of Communism. New York: The New Press, 1993, ix + 195 pp., $22.95. UK edition, The Squandered Dividend: The Free Market and the Environment in Eastern Europe. London: Earthscan Publications Ltd, 1993.

Jacques Nagels, La tiers‐mondisation de l'ex‐URSS? Brussels: Editions de l'Université de Bruxelles, 1993.

John Murray, The Russian Press from Brezhnev to Yeltsin: Behind the Paper Curtain. Aldershot, Hants: Edward Elgar, 1994, viii + 280 pp.

James D. White, The Russian Revolution 1917–1921. A Short History. London: Edward Arnold, 1994, viii + 312 pp., £12.99 p/b.  相似文献   

990.
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