Positively charged, oligolamellar liposomes were able to enter the pea pollen grains during the germination process in vitro. Large, identifiable liposomes could be found at a low frequency in living, germinated pollen grains and pollen tubes. Protoplasmic streaming inside the germinated pollen apparatus, where it appears as moving strands, exerts violent, formative effects on the liposomes. Up...

Cultured human synovial cells secrete hyaluronic acid (HA) into the culture medium. Glucosamine-6-(3)H was shown to be a direct and relatively specific precursor of HA-(3)H by the following observations: the susceptibility of nondialyzable radioactivity in the medium to hyaluronidase, its migration with hexuronic acid on zone electrophoresis in polyvinyl chloride, its exclusion from Sephadex G-...

To study the assembly of newly synthesized lipids with apoprotein A1, we administered [2-3H]glycerol to young chickens and determined the hepatic intracellular sites of lipid synthesis and association of nascent lipids with apoprotein A1. [2-3H]glycerol was rapidly incorporated into hepatic lipids, reaching maximal levels at 5 min, and this preceded the appearance of lipid radioactivity in the ...

PRESENT METHODS of measuring intestinal absorption of ra(lio-vitamin B12 iiuclude measurements of the radioactivity (1) in the feces, (2) over tIme liver projection, (:3) ii the serum, or (4) of the fraction of the al)sori'ed radioactivity excreted in the urine after the injection of a large amuiount of nonlabeled vitamin B12. \Vhile all these methods give clinically valuable results, Ilomie gi...

A general discussion is given for first-kind (FK) and quantum non-demolition (QND) measurements. The general conditions for these measurements are derived, including the most general one (called the weak condition), an intermediate one, and the strongest one. The weak condition indicates that we can realize a FK or QND measuring apparatus of wide classes of observables by allowing the apparatus...

A general discussion is given for first-kind (FK) and quantum non-demolition (QND) measurements. The general conditions for these measurements are derived, including the most general one (called the weak condition), an intermediate one, and the strongest one. The weak condition indicates that we can realize a FK or QND measuring apparatus of wide classes of observables by allowing the apparatus...