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131.
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The functional and nutritive circulation in the lungs is connected by anastomoses between the pulmonary and bronchial arteries. The anastomoses have the structure of blocked arteries from which arteriovenous anastomoses proceed to the peribronchial plexus. The pulmonary artery is provided with a flow impulse by the anastomoses, and oxygen-containing blood is admixed with the venous blood, thus forming an "aortalization" in the lungs. By diverting the bloodstream, venous blood can reach the bronchial artery. The peculiarities of the lung circulation are important for vital reactions in the form of macro- and microembolisms. Macroembolisms prove the functionality of the system if branches of the pulmonary artery are closed before the arteries are blocked. A hemorrhagic infarction either arises or does not arise, and the hemorrhagic infarction cannot exceed a certain limit. A microembolism is over and above the anastomoses. If the microembolism is greater, pressure in the arteria pulmonaris can cause blood from the pulmonary artery to overflow into the bronchial artery. Because arteriovenous anastomoses arise from the blocked arteries, microemboli can now reach the systemic circulation. Thus, the system described can explain the passage of microemboli into the systemic circulation, avoiding the capillaries of the lungs; on the other hand, larger microembolisms can prove the functionality of the system.  相似文献   
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Easterbrook G  Barry J  Thomas R  Clift E  Wingert  Hager M  Cohn B 《Newsweek》1992,120(22):30, 32-34, 36
Lobbyists, entrenched forces in congress and self-interested friends will try to stymie Clinton's efforts. A look at four key arenas of combat.  相似文献   
136.
The United States today faces a loss of influence as a world power, a reduction in American independence as a policymaker, and a decline in the standard of living on which Americans have come to depend. History teaches that nations weaker and less productive than the United States can rise to become economic powerhouses and rapidly increase their standards of living. History also teaches that nations failing to recognize their fundamental problems will inevitably decline. American politicians must face what is abundantly clear: the United States is losing ground and must act quickly to reverse its course. This White Paper outlines what must be done. Information about the nation's current status must be analyzed and communicated. Incentives to improve the level of competence in government must be provided and maintained. The emphasis of government policy must be changed to reflect broad economic and technological interests as opposed to special interests. Savings must be encouraged and increased. Infrastructure must be improved Tax laws must be modified to help bring these changes about. Economic and technological issues must be elevated to the importance they require. American thinking must reflect the new realities: that the age of leadership through military power is over, that the requirements for success in the world of the 1990s and beyond require a sound and growing economy that is internationally competitive. The US can accomplish these goals only through foundation-shaking, comprehensive, fundamental changealong the lines we propose herein.This paper is the executive summary (with minor editing modifications) of a white paper that is available from Cornell University's Johnson Graduate School of Management.  相似文献   
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The author incorporates geographic variables into this study of population dynamics in Michoacan, Mexico, during the eighteenth century.  相似文献   
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This study concerns the relationship between knowledge of drug culture and substance use. Results from a sample of 2,635 middle and high school students indicate that (1) knowledge of drug culture is positively correlated with substance use; (2) drug knowledge is more reliable and coherent in older youth; (3) drug knowledge is unrelated to other kinds of knowledge acquired in school; (4) youth exposed to peers' substance use in school have more drug knowledge; and (5) the earlier young people begin using drugs and alcohol, the more they know about the drug culture. Results suggest that knowledge of the drug culture may be an unobtrusive indicator of substance use problems.This project was made possible by a grant from the Tulsa Psychiatric Center, Tulsa, Oklahoma.Received Ph.D. from University of California at Berkeley in personality psychology. Research interests include school dropouts, substance use, delinquency, identity, narcissism, and health. To whom correspondence should be addressed.Received Ph.D. from University of California at Berkeley in personality psychology. Research interests include school dropouts, substance use, delinquency, personal commitments, identity, narcissism, and health.Received Ph.D. from University of California at Berkeley in personality psychology. Research interests include moral development and personality.  相似文献   
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Reviews     
R. W. Davies, ed., From Tsarism to the New Economic Policy. Continuity and Change in the Economy of the USSR. London and Basingstoke: Macmillan, 1990, xx + 417 pp., £45.00.

Alastair McAuley, ed., Soviet Federalism, Nationalism and Economic Decentralisation. Leicester and London: Leicester University Press, 1991, ix + 214pp., £38.00.

Loren Graham, ed., Science and the Soviet Social Order. Cambridge, MA and London: Harvard University Press, 1990, ix + 443 pp., £27.95.

Ronald I. McKinnon, The Order of Economic Liberalization: Financial Control in the Transition to a Market Economy. Baltimore, MD, and London: The Johns Hopkins University Press, 1991. xii + 200 pp., £20.00. $32.00.

Mary McAuley, Bread and Justice: State and Society in Petrograd 1917–1922. Oxford: Oxford University Press, 1991, xviii + 461 pp., £45.00.

David Armstrong & Erik Goldstein, eds, The End of the Cold War. London: Frank Cass & Co Ltd, 1990. 216pp., £19.50.

Paul B. Stephan III & Boris M. Klimenko, eds, International Law and International Security: Military and Political Dimensions. A US‐Soviet Dialogue. Armonk, NY, and London: M. E. Sharpe, Inc., 1991, xxii + 362 pp., $90.00.

Richard F. Staar, Foreign Policies of the Soviet Union. Stanford, CA: Hoover Institution Press, 1991, xl + 352 pp., £14.95 p/b.

Robert O. Freedman, Moscow and the Middle East: Soviet Policy Since the Invasion of Afghanistan. Cambridge: Cambridge University Press, 1991, xi + 426 pp., £35.00 h/b, £14.95 p/b.

Galia Golan, Soviet Policies in The Middle East: From World War II to Gorbachev. Cambridge: Cambridge University Press, 1990, ix + 319 pp., £27.50 h/b, £10.95 p/b.

Brian McNair, Glasnost, Perestroika and the Soviet Media. London and New York: Routledge, 1991, x + 231 pp., £35.00.

Shams Ud Din, ed, Perestroika and the Nationality Question in the USSR. New Delhi: Vikas, 1991, xv + 145 pp., £15.95.

Ronald J. Hill & Jan Zielonka, eds, Restructuring Eastern Europe: Towards a New European Order. Aldershot: Edward Elgar, 1990, ix + 226 pp., £28.50.

Aleksa Djilas, The Contested Country: Yugoslav Unity and Communist Revolution 1919–1953. London: Harvard University Press, 1991, v + 259 pp., £27.95 h/b.

Bartlomiej Kamiriski, The Collapse of State Socialism: the Case of Poland. Princeton, NJ: Princeton University Press, 1991, xiv + 264 pp., $39.50 h/b, $14.95 p/b.

David Ost, Solidarity and the Politics of Anti‐Politics. Opposition and Reform in Poland since 1968. Philadelphia, PA: Temple UP, 1990, xi + 279 pp. $34.95.

Roman Laba, The Roots of SolidarityA Political Sociology of Working Class Democratisation. Princeton, NJ: Princeton UP, 1991, xii + 247 pp., $24.95.

Keith Sword, ed, The Soviet Takeover of the Polish Eastern Provinces, 1939–41. London: Macmillan (in association with the School of Slavonic and East European Studies), 1991, xxiii + 318 pp., £45.00.

William B. Husband, Revolution in the Factory: The Birth of Soviet Textile Industry, 1917–20. New York and Oxford: Oxford University Press, 1990, viii + 227 pp. £25.00.  相似文献   

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