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Several compounds belonging to the group of para-substituted N-arylglycines have been found to exhibit pronounced tuberculostatic activity in vitro, but are too toxic for practical application. The relationship between chemical structure and activity is similar to that observed in the group of thiocarbanilides. [ABSTRACT FROM AUTHOR]

We have reproduced in Hordeum the phenomenon described by Schwartz: absence of proportionality at certain dosages, between the dose of roentgen rays and the biological effect when one irradiates dry seeds and measures the growth of the coleoptile. Cytological analysis shows an enlargement of the epidermic cells of the coleoptiles up to 500.000 r and a decrease of the number of mitosis up to 200.000 r dose at which the mitotic inhibition is nearly complete. The phenomenon described by Schwartz disappears progressively if one waits 3 to 20 days between irradiation and sowing. [ABSTRACT FROM AUTHOR]

In the rat, X-irradiation leads to a decrease of the net RNA and DNA content of the spleen, without, however, increasing the low molecular weight nucleic acid derivatives in the acid-soluble fractions of the same tissue. It is suggested that an alteration of the cell membranes could account for the apparent elimination of these nucleic acid degradation products which should normally appear in the acid-soluble fraction. [ABSTRACT FROM AUTHOR]

In 26 rabbits, the normal pH of the aqueous humor, measured with a glass electrode, was found to be 7.59±0.102. With an improved technique, the corresponding measures on ten other rabbits gave an average value of 7.57±0.043. Three hours after the injection of Diamox, a carbonic anhydrase inhibitor, a significant drop of 0.13 pH units was observed. These effects seem to be dependent on the inhibition of the ciliary body carbonic anhydrase; however there may be some participation of the metabolic acidosis of renal origin. The fall of pH in aqueous humor produced by Diamox is to be correlated with the decrease of potassium concentration previously reported; these facts suggest the hypothesis of a competition between potassium and hydrogen ions in the secretion of aqueous humor. [ABSTRACT FROM AUTHOR]

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l-Adrenaline, l-nor-adrenaline, isopropyl-nor-adrenaline and adrenochrome potentiate the maximal twitch of the unfatigued mammalian muscle. This phenomenon is increased by an excess of calcium ions in the surrounding fluid. These substances act directly on the muscle fibre, in a completely curarized preparation. [ABSTRACT FROM AUTHOR]

Weber's technique of silver impregnation permits one to observe a distinct dichroism of nuclear crystals. The dichroism proved a texture of fibrous type. [ABSTRACT FROM AUTHOR]

A study has been made of the chromosomes of Blaps mortisaga L. The diploid number is 36. There are four sex-chromosomes which form a single configuration at the first division of maturation and disjoin so that three pass to one pole and the fourth to the other. A further study will be made on the female to indentify the type of the sex-chromosomes. [ABSTRACT FROM AUTHOR]

Although vasoconstrictor properties have been clearly demonstrated in the venous renal blood after renal ischemia, we have not been able to detect such properties after hypotension in the carotid sinuses or after bleeding in the dog. [ABSTRACT FROM AUTHOR]

The Ghent strain of Treponema pallidum loses entirely its virulence for the rabbit when mixed in vitro during 1 hour at 18° C or 3 hours at 37° C with a solution of 'penicillin sodium Chas. Pfizer & Co., Inc.' or with 'penicillin C.S.C. sodium salt of the Commercial Solvent Corporation' at the rate of 10,000 Oxford units per cm. The injection of 20,000 units in each testicle of the animal, when made immediately before or at the same time as the inoculation of the virus, does not protect against the infection. It is therefore possible to prevent syphilis by penicillizing the blood for transfusion. But too great amounts of the drug are required in practice. It must also be proved that chemically pure penicillin has the same treponemicid action. [ABSTRACT FROM AUTHOR]

Radioactive 2-bromo-3-hydroxy-1:4-naphtoquinone has been used for the exploration of the metabolism of substances which influence the course of blood-clotting. It has been found that this substance diffuses very rapidly into the blood, and that the liver is not characterized by any elective fixation-power. [ABSTRACT FROM AUTHOR]

Polygraphic recordings of human sleep are automatically analyzed by an original device, consisting of an analog component and a digital component (small computer). The device gives a minute by minute diagnosis of sleep stage, along with comments (artefacts) and numerical results for rapid and slow eye movements, muscle tone, heart and respiratory rates. [ABSTRACT FROM AUTHOR]

The locust Locusta migratoria L. transforms β-sitosterol into cholesterol. Fucosterol, desmosterol and an unknown sterol (probably in C) are found to be intermediates, but not 24-methylene cholesterol. [ABSTRACT FROM AUTHOR]

Counts were made of the numbers of germ cells in quail embryos aged 4-7 days' incubation. The rate of growth in the population of gonocytes was compared to these of chick and turkey embryos during the same period. The increase is exponential in the three species and the rates are more similar between quail and turkey than between each of them and the chick. [ABSTRACT FROM AUTHOR]

The renal tubular fate of urea, as studied in the rat by free-flow micropunctures of cortical tubules, is shown to vary with different types of diuresis (urea overloading, iso- or hypertonic saline diuresis). Under certain experimental conditions, the renal tubular handling of urea appears to differ in the cortical and the juxtamedullary nephrons. [ABSTRACT FROM AUTHOR]

Preceding the infolding of the cross wall separating pseudoconidial units in the aschizogenous, 'amyc' mutant of Neurospora crassa is the development of an electron-dense ring seen in section as 2 spots on opposite sides of the cell wall. Vesiculated elements of the endoplasmic reticulum are seen in close proximity to the centripetally progressing edge of the interconidial septum. [ABSTRACT FROM AUTHOR]

In the Tench the section of the both vagi induces a decrease of the hematocrit value, which is probably due to an increase of the blood volume. Several weeks after cutting the parasympathetic system, the value of the hematocrit returns to normal. This normalization may be due to nervous regeneration or to endocrine changes. [ABSTRACT FROM AUTHOR]

The chromosome complement of Sorex minutus L. has been determined. The caryotype is characterized by a diploid number of 42 and by a NF (fundamental number) of 56. The sex-chromosomes are of the X−Y type usual in mammals. The origin and the evolution of the chromosome set of S. minutus, S. unguiculatus, and S. araneus have been discussed. [ABSTRACT FROM AUTHOR]

Copyright of Experientia is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Irradiation of an internodal cell of Nitella flexilis induces in the adjacent internodal cell a transitory acceleration of cytoplasmic streaming; during 8 h at least the speed of this streaming is higher than in control internodal cells. It is probable that this phenomenon is due to transfer of certain substances from the irradiated cell. [ABSTRACT FROM AUTHOR]