Why scientists perform animal experiments, scientific or personal aim?

SummaryVarious renal imaging agents that were reported in the past and a new agent, 99mTc-malate as well as 99mTc-cystein acetazolamide complex were prepared using electrolysis and electrochemical methods. These were studied for their labelling efficiency. After animal experiments with selected 99mTc-com- pounds, 99mTc-rnalate proved to be sufficient for renal imaging with adequate concentration. 99mTcmalate differs from other renal imaging agents in the utilization of endogeneous metabolic product.The first half time of 99mTc-malate in humans is 17 minutes, on the average, and the urinary excretion rate of 99mTc-malate is 36±6.05% in 1 hour after intravenous administration, 44 ± 3.41% in 2 hours and 50 + 5.62% in 3 hours.In our 40 clinical experiences of 99m-Tc-rnalate, most cases demonstrated quite clear renal images in the serial scintiphotos except cases whose serum creatinines were over 4.5 mg/dl.

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Clinical and Experimental Analysis of 201Thallium Uptake of the Heart

Nuklearmedizin ◽

10.1055/s-0037-1620682 ◽

1978 ◽

Vol 17 (04) ◽

pp. 142-148

Author(s):

U. Büll ◽

S. Bürger ◽

B. E. Strauer

Keyword(s):

Oxygen Consumption ◽

Left Ventricle ◽

Muscle Mass ◽

Myocardial Oxygen Consumption ◽

Animal Experiments ◽

Left Ventricular ◽

Left Ventricular Wall ◽

Ventricular Wall ◽

Flow Measurements ◽

Myocardial Flow

Studies were carried out in order to determine the factors influencing myocardial 201T1 uptake. A total of 158 patients was examined with regard to both 201T1 uptake and the assessment of left ventricular and coronary function (e. g. quantitative ventriculography, coronary arteriography, coronary blood flow measurements). Moreover, 42 animal experiments (closed chest cat) were performed. The results demonstrate that:1) 201T1 uptake in the normal and hypertrophied human heart is linearly correlated with the muscle mass of the left ventricle (LVMM);2) 201T1 uptake is enhanced in the inner (subendocardial) layer and is decreased in the outer (subepicardial) layer of the left ventricular wall. The 201T1 uptake of the right ventricle is 40% lower in comparison to the left ventricle;3) the basic correlation between 201T1 uptake and LVMM is influenced by alterations of both myocardial flow and myocardial oxygen consumption; and4) inotropic interventions (isoproterenol, calcium, norepinephrine) as well as coronary dilatation (dipyridamole) may considerably augment 201T1 uptake in accordance with changes in myocardial oxygen consumption and/or myocardial flow.It is concluded that myocardial 201T1 uptake is determined by multiple factors. The major determinants have been shown to include (i) muscle mass, (ii) myocardial flow and (iii) myocardial oxygen consumption. The clinical data obtained from patient groups with normal ventricular function, with coronary artery disease, with left ventricular wall motion abnormalities and with different degree of left ventricular hypertrophy are correlated with quantitated myocardial 201T1 uptake.

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Bestimmung des zerebralen Blutflusses mittels des 81 Rb/81 mKr-Generatorsystems

Nuklearmedizin ◽

10.1055/s-0038-1629505 ◽

1990 ◽

Vol 29 (01) ◽

pp. 7-12 ◽

Cited By ~ 1

Author(s):

J. Bialy ◽

F.-J. Hans ◽

E. Oberhausen ◽

W.J. Peters ◽

M. Schmitt ◽

...

Keyword(s):

Blood Flow ◽

Cerebral Blood Flow ◽

Blood Circulation ◽

Semiconductor Device ◽

Animal Experiments ◽

Initial Value ◽

Brain Arteries ◽

Sufficient Concentration ◽

Static Quantity

A method is being developed which not only measures cerebral blood flow as a static quantity but also its changes with time. For that purpose a semiconductor device ascertains the proportion of intracerebral81 Rb and 81mKr activities. By opening the haemato-encephalic barrier in animal experiments a sufficient concentration of intracerebral81 Rb could be attained and the modified blood circulation after step-wise ligature of all brain arteries brought into relation to the corresponding Rb/Kr quotient. Over the range from undisturbed to completely interrupted cerebral blood flow this quotient varied up to 25% of its initial value.

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Investigation into Cigarette Smoking and Atmospheric Pollution in the Aetiology of Lung Cancer

Methods of Information in Medicine ◽

10.1055/s-0038-1636169 ◽

1963 ◽

Vol 2 (01) ◽

pp. 13-19 ◽

Cited By ~ 2

Author(s):

R. Doll

Keyword(s):

Lung Cancer ◽

Cigarette Smoking ◽

Atmospheric Pollution ◽

Direct Evidence ◽

Retrospective Studies ◽

Common Factor ◽

Animal Experiments ◽

Smoking Habits ◽

Careful Examination ◽

Ancillary Data

The evidence that cigarette smoking and atmospheric pcllution are causes of lung cancer is largely statistical. The first evidence was indirect; that is, i1. was noticed that in many countries the incidence of lung cancer had increased and that the increase could be correlated with changes in the prevalence of cigarette smoking and of certain types of atmospheric pollution.Since then much direct evidence has been obtained. The relationship between cigarette smoking and lung cancer has been demonstrated retrospectively by comparing the smoking habits of patients with and without lung cancer and prospectively by observing the mortality from lung cancer in groups of persons of known smoking habits. Conclusions can be drawn from these studies only after careful examination of the results. In particular it is important in retrospective studies to test a) the reproducibility of the data, b) the representativeness of the data, and c) the comparability of the special series and their controls. The resul1.s of retrospective studies are all similar and all show a close relationship between cigarette smoking and the disease.The results have been confirmed by pro~pective studies which are lesF. open to bias. The results can be explained if cigarette smoking causes lung cancer or if both are related to some third common factor. Ancillary data (pathological changes in the bronchial mucosa, animal experiments, etc.) support the causal hypothesis.The evidence relating to atmospheric pollution is less definite and it is difficult to get direct evidence of a relationship in the individual. It is clear that pollution has little effect in the absence of smoking, but the mortality associated with a given amount of smoking is generally greater in large towns than in the countryside and among men who have emigrated from Britain than among men who have lived all their lives in less polluted countries.

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Basic Problems of Logic in Drug Investigations

Methods of Information in Medicine ◽

10.1055/s-0038-1636154 ◽

1974 ◽

Vol 13 (04) ◽

pp. 248-253

Author(s):

H. Röpke

Keyword(s):

Animal Experiments ◽

Point Of View ◽

Applied Logic ◽

Clinical Investigations

The basic problems of the theory of cognition when extrapolating the results of animal experiments to man and the limitations of inferences from clinical investigations of drugs are discussed from the point of view of applied logic.

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