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951.
How long should drug therapy for depression be maintained? 总被引:1,自引:0,他引:1
M T Abou-Saleh 《The American journal of psychiatry》1987,144(9):1247-1248
952.
C Holubarsch G Hasenfuss C Chen R Tarnowska T Bonzel H Just 《Zeitschrift für Kardiologie》1987,76(6):340-345
We analyzed performance and efficiency of the left ventricular myocardium on the basis of two new energetic parameters. The myocardial energy consumed during one cardiac cycle is related to performed work on the one hand (E1) and to the stress-time-integral on the other (E2). E1 was obtained by analysis of the pressure-volume integral divided by left ventricular muscle mass. E2 was obtained as follows: the stress-time integral was analyzed from pressure-volume data and wall thickness using an ellipsoidal calculation model. In order to transfer the stress-time integral into energy units, the value was multiplied by a constant factor which was obtained in experimental myothermal studies. In ten patients with coronary heart disease undergoing diagnostic heart catheterization, angiocardiography was performed before and after oral administration of nitroglycerin (1.6 mg). Total energy consumption (2E1 + E2) per gram myocardium per beat decreased from 6.1 +/- 1.3 mcal/g to 4.7 +/- 1.4 mcal/g (P less than 0.01), and myocardial efficiency (E1/[2E1 + E2]) increased from 27.0 +/- 3.1% to 28.4 +/- 4.3% (N.S.) on the average. This analysis explains quantitatively the beneficial effect of nitro-preparations on myocardial function and energetics. 相似文献
953.
954.
955.
T Yoshimoto K Higashino T Hada S Tamura K Nakanishi M Mitsunobu K Uematsu T Matsuoka K Taketa 《Cancer》1987,60(11):2744-2750
This article documents a patient with lung carcinoma that produced three oncofetal antigens including alpha-fetoprotein (AFP), carcinoembryonic antigen (CEA), and human chorionic gonadotropin (hCG). Serum AFP, CEA, and hCG-beta-subunit were extremely high--118,000 ng/ml, 133 ng/ml and 0.9 ng/ml, respectively. Immunohistochemical staining of these tumor markers revealed that these proteins were present in different cells. The pattern of lectin affinity electrophoresis of AFP resembled that of hepatocellular carcinoma. Also investigated was the reactivity of serum CEA to monoclonal antibodies against peptide or sugar moieties. Serum CEA values measured by antipeptide monoclonal antibodies were higher than those measured by antisugar monoclonal antibodies. The demonstration of AFP, CEA, and hCG in different tumor cells suggests that three genomes were not reactivated together in a cell, and the lung carcinoma probably consisted of at least three clones of cancer cells with different phenotypes. 相似文献
956.
The biological response to ambient air pollution may be a function of specific combinations of pollutants. Groups of rabbits were exposed to NO2 (0.3 ppm or 1 ppm) with and without H2SO4 (0.5 mg/m3) for 2 hr/day for up to 14 days for assessment of effects upon mucociliary clearance of tracer particles from the tracheobronchial tree. Exposure to NO2 did not alter clearance, while exposure to H2SO4 produced a retardation toward the middle of the exposure series. The combination of 0.3 ppm NO2 with H2SO4 resulted in a speeding of clearance, while no change from control was seen with the mixture employing 1 ppm NO2 with acid. These results emphasize the importance of performing studies with pollutant mixtures, since it is not always possible to extrapolate responses from studies examining effects of individual pollutants. 相似文献
957.
Free radical mechanisms in relation to tissue injury 总被引:4,自引:0,他引:4
958.
959.
C E Rupprecht L T Glickman P A Spencer T J Wiktor 《American journal of epidemiology》1987,126(2):298-309
Rabies virus was isolated by cell culture from the brains of 104 confirmed rabies cases diagnosed by the fluorescent-antibody staining technique in the United States during 1974-1984. Eighty-seven isolates were obtained from wild-life species, 10 from humans, and seven from domestic animals. These isolates were tested in virus neutralization and immunofluorescence assays using a panel of 34 monoclonal antibodies specific for rabies virus nucleocapsid protein, 44 monoclonal antibodies specific for rabies virus glycoprotein, and two monoclonal antibodies specific for rabies virus nucleocapsid-associated phosphoprotein. Using discriminant analysis, a distinctly different reactivity pattern was revealed between virus isolates from terrestrial (raccoon, skunk) and nonterrestrial (bat) reservoir hosts. The usefulness of this approach for studying the epidemiology of rabies and for predicting the source of infection when this information is unknown is discussed. 相似文献
960.