A simple method of preparing permanent squash preparations using cellophane]

A technique to prepare permanent squashed preparations of cell nuclei and chromosomes is proposed. Fix a piece of material on the slide with acetic alcohol (1:3), macerate with a 45% acetic acid, cover with hydrophilic cellophane previously soaked in a 45% acetic acid and then with a cover slip and filter paper to squash finally as it is routinely performed. After that soak off the cover slip with alcohol, post-fix the squashed preparation together with cellophane in alcohol for 5-10 min, unstick the cellophane, pass the preparation through alcohol once again and dry it. The subsequent treatment of the squashed preparation depends on the purpose of investigation. The slide may be tinctured overlaid with photoemulsion for autoradiography, or processed by different ways.     

Hemoglobin polymers during their circulation in the vascular bed of animals

The effect of molecular mass of 1 g/kg hemoglobin (Hb) modified by glutaraldehyde and pyridoxal-5'-phosphate on the duration of Hb presence in the rabbit circulation was studied. Hb concentration and met-form content were measured in plasma samples taken 5 min, 6, 18 and 24 h after the injection. Gel and ion exchange chromatography was performed. Predominant clearance of low-molecular fractions within the first 6 h of circulation was shown, it was followed by a rise in high-molecular fraction (greater than 300,000) content, that might be caused by the interaction of modified Hb with plasma proteins. This corroborates the decrease in the overall charge of the circulating fractions.     

A new method of collection of gastric juice from small animals]

A new method is suggested to obtain gastric juice in small animals. This technique is considered to be preferable in comparison with other known techniques as it permits obtaining gastric juice without surgery which is inevitably associated with such unfavourable factors as tissue traumas, pain irritation, inflammation, etc. According to the described technique the gastric juice is collected with the presence of stimulus (dry substance) in the gastric cavity. The animals are not fixed in this case but maintained under ordinary conditions. So, the obtained juice corresponds better to that produced in small animals under physiological conditions than the juice obtained using fistula or by another technique applied up to now.     

A method for the estimation of striated muscle mass in small laboratory animals.

A method for the determination of the total muscle mass in small experimental animals is presented. Muscle proteins were quantified in the 1 M LiCl-soluble and distilled water-insoluble fraction of the eyeless, brainless, eviscerated and skinned carcass, as compared with a striated muscle sample from the same animal used as standard and processed in the same way as the whole carcass. The non-muscular tissues left in the carcass do not interfere with the final results. The total muscle mass in adult rats was estimated as 42.0 +/- 2.8% of the in vivo weight.     

Lymphatic bed of the muscular sheath of the small intestine in animals and man during ontogenesis]

In the anatomy of the lymphatic bed of the small intestine muscle layer still there are obscure questions on the phylo- and ontogenesis of man and animals. Under study were 92 corpses (35 men, 27 cats and 30 dogs) of different age, beginning from the intrauterine period to old age. Different methods were used: polychromatic injection; macro- and microscopic dissection; staining after van Gieson and with haematoxilineeosin; impregnation with 0,25-1% solution of silver nitrate; dehydration and clearing; counting of the density of loops per a mm2 and the depth of their disposition in the intestinal wall with an ocular-micrometer. It was shown that formation of the lymph capillaries and their network in cats, dogs and man began from the end of the intrauterine period, was completed in new-borns and became sufficiently developed in young age. The structure of the lymph capillary networks is closely connected with the development of the muscle layer of the small intestine. Formation of the lymph lacunas begins after birth. With age the lymph capillary network becomes looser, the loops break and their size enlarges.