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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   
34.
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   
35.
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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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   

38.
A new structure of conclusions including special chapter "Conclusion validity", which ensures their high availability for officials of legal investigation agencies is suggested. The examples of conclusion making on the basis of new form in case of blood, secretion and hair tests performed in two variants (known and unknown criminal) are presented.  相似文献   
39.
During preliminary examination of the body of a homicide victim, a peculiar red "fiber" was noticed and recovered. Initially believing this to be a carpet fiber, the item was subjected to fiber analysis. It was found to be a short coiled particle not like any known natural or synthetic fabric fiber. Subsequent examinations determined this "fiber" to be the larva of a common freshwater midge (Diptera; Chironomidae). Chironomid larvae have been observed on other bodies recovered from freshwater environments. Entomological studies of this organism have led to the conclusion that the presence of chironomid larvae indicates submersion of the body.  相似文献   
40.
Isoenzyme band patterns of animal blood erythrocyte acid phosphatase (EAP) and phosphoglucomutase-1 (PGM) were studied by isoelectric focusing on ultrathin polyacrylamide gels. For blood from all animals tested (dog, cat, cow, sheep, and goat), the overall band patterns for both isoenzymes were different from those of the most common human types of these enzymes, although some animal EAP and PGM bands appeared in the human band areas. When mixtures of human and animal red blood cells were studied, it was found that misinterpretation of human types was possible only if the overall band pattern of the mixtures was ignored. For the animal blood tested, the strong PGM bands appearing outside the human band areas could be used as "markers" for the possible presence of animal blood in the samples tested.  相似文献   
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