Several years ago we started a broad research project dealing with the relation between the level of endogenous growth substances and the development of avocado fruit. In the course of the study, we attempted to grow cultures of avocado fruit tissue and to determine their response to the addition of growth substance. It was hoped that in this way we might learn something about the special natur...

Unbranched tendrils arising from the fifth node of light grown Alaska pea plants were found to reach maturity at the age of 10 days. Such tendrils, when stroked, coiled rapidly. They remained maximally irritable for at least 3 days.Coiling was separable into 2 components, curvature (measured in degrees) and elongation. Coiling reached a maximum from one-half to 3 hours after tactile stimulation...

'I'lle l)lalt p)ignent, phytochrome regulates a large numl)er of l)hysiological processes in higher plaints (14). T'he pigment is nmost readily detected in darkgrown see(llings both because it is normally present in higher conlcenitrationis than in light-grown seedlinigs (8, 11), and because dark-grown seedlinigs contain only smlall amounts of other pigments absorbing ligfit ini the same spectr...

Various aspects of the problem of growth stimulation of tissues have been emphasized recently. From experiments with tissue cultures Carrel (1) has obtained results showing that leucocytes have a growth-promoting function, that they give off substances which stimulate the growth of adjacent cells. These growth-promoting substances he has named trephones (2). On the basis of the specific differe...

apparently had some qualms) there can be disagreement; since further experience will doubtless settle these questions, there is no point discussing any of them here. The text is divided into twenty chapters, grouped in three units, on nutrition, metabolism, and growth and development. The first unit treats photosynthesis, mineral and water relations, and translocation. The second part includes ...

since particulate matter (total suspended particles and particulate matter with median aerodynamic diameter less than 10 µm) is one of the important pollutants in the ambient air of tehran, the capital of iran, organic substances, inorganic substances and lead levels in tsp and pm10, correlation between tsp and pm10 concentrations, ratio among the two fractions and relation between tsp and pm10...

Our later investigations confirm our previous results. 1. It is possible to increase markedly the effect of substances inhibiting tumor growth by using certain combinations of these substances which, when given alone, have some effect on tumor growth. 2. Immunity acquired against the effect of these substances depends partly upon an active immunization of the tumor cells themselves against the ...

The growth of all the pathogenic bacteria studied was favorably influenced by the addition of small amounts of tissue extracts. Beef heart, rabbit and cat tissues, and human nasal secretions contain substances favorable to the growth of the organisms tested. The mucosa of different organs, spleen, liver, and kidney, are relatively rich in these substances, while muscle is relatively poor. The f...