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971.
Molsidomine (M) is a new antianginal drug which induces a peripheral venous pooling and decreases pulmonary artery and pulmonary venous pressures. The purpose of our study is to assess whether M influences the filling of the pulmonary capillary bed as estimated by the single-breath lung diffusing capacity (DLCO). DLCO was measured before and 10, 20, 30, 40, 50 and 60 minutes after sublingual administration of 2 mg molsidomine in six healthy men examined in sitting and supine positions. The blood flow distribution was estimated by means of radioactive xenon, in sitting position only, before and 30 minutes after M intake. M. induces a significant fall in DLCO from the 20th to the 60th minute which indicates an emptying of the pulmonary capillary bed. Concomitantly, blood flow is redistributed from the apices to the lung bases. We explain the decrease in DLCO by two mutually non-exclusive mechanisms: an outflow of the blood from the thorax to the periphery and a change in the lung-perfusion distribution. From a practical point of view, two conclusions may be reached. First, in coronary patients a decrease in DLCO and DLCO/VA may be due to the intake of vasodilating agents such as molsidomine and not to emphysema or lung fibrosis. Secondly, the measurement of DLCO is a useful tool to assess the action of a drug on the pulmonary circulation. 相似文献
972.
Martin Van den Berg Frans Blank Carola Heeremans Hans Wagenaar Kees Olie 《Archives of environmental contamination and toxicology》1987,16(2):149-158
In the period 1980 to 1982, nineteen CormorantsPhalacrocorax carbo, three Grey HeronsArdea cinerea and one Great Crested GrebePodiceps crisatus were collected in The Netherlands. The livers of these fish-eating birdspecies were analyzed for polychlorinated dibenzo-p-dioxins and dibenzofurans.Only congeners with a 2,3,7,8-chlorine substitution pattern were found in the livers. Major components were 2,3,4,7,8-pentachlorodibenzofuran and 1,2,3,6,7,8-hexachlorodibenzo-p-dioxin, 2,3,7,8-tetrachlorodibenzo-p-dioxin and 1,2,3,7,8-pentachlorodibenzo-p-dioxin were also present. Six pooled samples of the EelAnguilla anguilla, showed the same congeneric pattern of chemicals as found in these bird species. In the Eel, 2,3,4,7,8-pentachlorodibenzofuran and 1,2,3,6,7,8-hexachlorodibenzo-p-dioxin were generally present in the 1 to 5 ng/kg range. Since the Eel is the Cormorant's 2 major food, this indicates strong bioaccumulation for both congeners in the liver of the Cormorant.Significant correlations were found between the various congeners retained in the liver of the Cormorant. It is proposed that this is a result of a continous exposure to a relatively stable background mixture, probably originating from fish consumption. Based on the congeneric patterns found in the Cormorant, polychlorinated biphenyls and pentachlorophenol are suggested as major contaminating sources for this species. Based on the results from the Cormorants, an open one compartment model was applied to estimate concentrations of 2,3,4,7,8-PnCDF in the Eel. These calculations were in good agreement with the actual measurements found in the Eels. 相似文献
973.
Nijhuis Ilse J. M.; van Dael Carin M. L.; Bink-Boelkens Margreet T. E. 《Nephrology, dialysis, transplantation》2005,20(2):472
Sir, Recently, we delayed starting continuous veno-venous haemofiltration(CVVH) treatment because we were reluctant to perform directcurrent (DC) cardioversion during CVVH. In the end, it provedto be no problem. Case. A 15-year-old, 相似文献
974.
975.
976.
Frans C. Visser Gerrit Westera Machiel J. van Eenige Ernst E. Van der Wall Wim Den Hollander Jan P. Roos 《European journal of nuclear medicine and molecular imaging》1985,10(3-4):118-122
To clarify the mechanism of the elimination of radioactivity after administration of radioiodinated heptadecanoic acid, dogs with and without coronary occlusion were studied. In myocardial tissue samples of normal and ischemic myocardium, the proportions of free radioiodide, radioiodinated heptadecanoic acid, and radioiodinated lipids were determined. Five minutes after intravenous injection of heptadecanoic acid 69% of the radioactivity was present as free iodine, 7% as unaltered heptadecanoic acid, and 24% as lipids. Even in ischemic myocardium 41% was free iodine and 47% lipids. After 2 h free iodine decreased to 48% and lipids increased to 44%. These results indicate that beta-oxidation is not the rate-limiting step in the elimination rate of heptadecanoic acid. 相似文献
977.
J G Nijhuis 《European journal of obstetrics, gynecology, and reproductive biology》1986,21(5-6):301-308
Behavioural states do exist in the human fetus. These states have been called 1F to 4F and resemble states 1 to 4 in the neonate. States 1F and 2F are similar to 'non-REM sleep' or 'quiet sleep' and 'REM-sleep' or 'active sleep', respectively. The fetus spends most of the time in these two states. Each state can be characterized by a particular combination of 3 variables: presence or absence of fetal eye movements and body movements, and fetal heart rate patterns A, B, C and D. From about 36 wk these combinations can be recognized during longer periods without interruptions, and with clear state-transitions. At 32 wk a certain linkage between the three variables is already present but a step-wise increase can be seen between 36 and 38 wk. Fetal breathing, mouthing movements and fetal voiding are state concomitants. Breathing movements are much more regular during state 1F than during state 2F, while the incidence is increased in 2F. It is demonstrated that knowledge of fetal behavioural states is necessary for an adequate interpretation of the fetal heart rate patterns. The concept of behavioural states may be useful for the early detection of disturbances of the developing fetal nervous system. It is therefore concluded that further studies on fetal behaviour have to be 'standardized' for behavioural states. 相似文献
978.
Journal of Thrombosis and Thrombolysis - 相似文献
979.
980.