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991.
The authors have shown an heterogeneity of the ovine prolactine molecule after labelling with iodine 125. As well with chloramine T as with lactoperoxydase, it appears three molecular species which react with the immune serum antiprolactine (I.S.). The first species is of high molecular weight and is probably constituted of aggregates. Their combination with the I.S. is non specific and give blanks of high value. The second species is a dimere and the third one is the monomere. The two last species react with the I.S. and can give competition curves when they are choosen as tracer. However, if one uses as tracer a product obtained by labelling with chloramine T, the competition appears for high concentrations of native hormone. As if the I.S. recognizes much more the labelled protein than the native one. But if one uses the same species but labelled with lactoperoxydase, the competition appears for concentrations lower than five nanogrammes. In the same time one can see that the specificity toward different I.S. is modified. The authors think that the labelling with lactoperoxydase better preserves the tertiary structure of the native protein than do the labelling with chloramine T.  相似文献   
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993.
On the model of biofeedback connection by the given parameters of the EEG alpha-rhythm the dynamics of bioelectrical and vegetative characteristics and correlative connections between them were compared in the pairs of mono- and dizygotic twins. More likeness in the dynamics of the studied parameters was found in the pairs of genetically identical monozygotic twins. There was a maximum increase of the objective similarity characteristics in the moment of activity realization, judging by the change of alpha-rhythm parameters. The obtained results testify to genetic determination of individual specific styles in organization of complex integrative processes of the higher nervous activity.  相似文献   
994.
Experimental infection of mice with Toxocara canis provides one of the best models for immunological and pathological studies of the visceral larva migrans syndrome. Blood eosinophilia, the migratory behaviour of second stage larvae and granuloma formation were studied in Swiss mice infected with Toxocara canis. Eosinophilia, spleen, liver and lung indexes were followed during a primary infection with different inoculum sizes (500 and 1500 eggs) while the migratory behaviour of larvae was studied in a primary infection with 1500 eggs over a period of 4 months. In mice infected with three challenges of 1500 eggs in order to elicit a strong inflammatory reaction in the tissues, a histopathological study was carried out. The results showed that eosinophilia, spleen and lung indexes (but not the liver index) were influenced by the parasite inoculum size. The migratory behaviour study showed that larval recovery was maximal three days post-infection, from the liver and lungs; the peak recovery from the skeletal muscles and brain being on days 15 and 30 post-infection, respectively. The histopathological study revealed the formation of granulomas in all the tissues examined (liver, lungs, kidneys, spleen, lymph nodes, myocardium etc.) but not in nervous tissue or in the retina of the eye. Granulomas in the lungs were larger than those found in the liver. The implications of these results are discussed considering host-parasite inter-relations.  相似文献   
995.
In 1983 a WHO collaborative study showed that the single radial immunodiffusion test provided a reliable system for the assay of the glycoprotein content of inactivated rabies vaccines. We have modified the method used in the collaborative study by using round plastic plates with wells arranged in a circle. Potency estimates were made by the multiple slope ratio method and not by single slope estimation procedures adjusted for a common intercept. We carried out a statistical evaluation of the accuracy and reliability of the precipitation area calculation. We confirmed that for the purpose of the potency estimation the area calculations were sufficiently precise in most instances. By analysing the sources of variation for round and for glass plates and by testing the variability of these methods we found that the round plates were as good as the glass plates. The advantage of the round plates was mainly in the ease of their handling: the agarose solution was poured in the plates without the need for a separate mould; an integral moist chamber with these plates was readily available; the precipitation zones were measured easily using a viewer which gave fourfold enlargements and the method required less antiglycoprotein.  相似文献   
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999.
Pharmacodynamical analysis of alpha-adrenergic and beta-adrenergic reactions of sheep rumen was performed in vivo after administration of agonists and antagonists of alpha-adrenergic and beta-adrenergic receptors. It was found that phenylephrine, and in a lower degree propranolol, stimulated the motor activity of sheep rumen, while adrenaline, noradrenaline, isoprenaline, phenoxybenzamine and regitine depressed this activity. Propranolol abolished atonia produced by catecholamines in sheep rumen, and previous blockade of beta-adrenergic receptors with propranolol reversed the relaxing action of catecholamines on the muscular elements in the rumen. The experiments in vivo confirmed the adrenergic effects on the motor activity of the rumen of sheep obtained in earlier investigations on isolated muscles of the rumen. It is suggested that noradrenaline exerts an ambireceptro effect (similar to that of adrenaline) on the motor activity in sheep rumen.  相似文献   
1000.
The present study has attempted to determine the volume, square measure as well as length, width and thickness of the individual muscles of facial expression by photogrammetry. 15 fresh male head specimens were employed for a careful dissection of muscle layers. The volume was measured using the immersion procedure. The mean values of each parameter together with the standard deviation were summarized. The results suggest that this novelty in the representation of the mimetic muscles will facilitate the planning of corrective interventions in plastic surgery. Moreover, photogrammetry offers additional information on the required size and measurements of donor muscles.  相似文献   
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