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761.
762.
Presence of a non-acidic, growth-promoting indole compound, identical in Rf and colour reaction and closely similar in UV spectrum to synthetic indoleacetaldehyde (IAAId) has been demonstrated in extracts of etiolated shoots of Pisum and Helianthus. On chemical as well as enzymic oxidation of this neutral extract, activity passes over into the acidic fraction. This neutral substance is believed to be IAAId and occurs in the free state as short-term, low temperature extractions indicate. On the basis of Rf, colour reaction and UV spectrum, tryptophol has also been identified in Helianthus extracts. Its identification in pea extracts, however, rests only on Rf, colour reaction and inactivity in Avena bioassays.  相似文献   
763.
Staphylococcal enterotoxins (SEs) are liked with food poisoning and other related infections. Nafcillin is an antibiotic used to treat S. aureus. Therefore, it is of interest to study the molecular interactions of 25 nafcillin analogues with enterotoxin I using molecular docking analysis. The analysis shows optimal interaction features of Nafcillin analogues with Enterotoxin I from Staphylococcus aureus for further consideration.  相似文献   
764.
Measurements of active, standard and routine oxygen consumption were made for 207 Utah chub at 6°, 9°, 12°, 18° and 22° C; and 123 speckled dace at 4°, 8°, 12° and 18° C. These were expressed as mathematical functions of water temperature and size of the fish. The mean slopes of loge oxygen consumption (mg O2/h) and loge wet weight (g) were 0.771, 0.526, and 0.619 for active, standard, and routine rates respectively for Utah chub, and 0.943, 0.486, and 0.683 respectively for speckled dace.  相似文献   
765.
766.
767.
Photosynthetica - Phosphoenolpyruvate carboxylase (PEPC) was purified from leaves of four species of Alternanthera differing in their photosynthetic carbon metabolism: Alternanthera sessilis (C3),...  相似文献   
768.
Elvers of Anguilla nebulosa were reared at 23°C in confined waters and their food intake, growth and conversion efficiency (K1:%) were studied. Elvers weighing 278.33±14.35 mg were fed on an ad libitum diet of the oligochaete worm Tubifex tubifex for 60 days. On an average, the test individuals consumed 99.55±19.81 mg food/elver/day amounting to 35.76% of the initial biomass; during the corresponding period the elvers exhibited a growth rate of 5.03±2.42 mg gain in weight/elver/day which is equivalent to 5.06% of the consumed food. Thus the 'housekeeping' of these elvers may be regarded as established. In 50 days, the food required amounts to 0.358±50 = 17.90 times the initially stocked biomass. That is, 1 kg of initially stocked elvers may need 17.90 kg of T. tubifex to produce 0.912 kg of elver meat. A poor conversion ratio of 20 : 1 may be one reason for the slow growth of the elvers.  相似文献   
769.
770.
The remarkable deformability of red blood cells (RBCs) depends on the viscoelasticity of the plasma membrane and cell contents and the surface area to volume (SA:V) ratio; however, it remains unclear which of these factors is the key determinant for passage through small capillaries. We used a microfluidic device to examine the traversal of normal, stiffened, swollen, parasitised and immature RBCs. We show that dramatic stiffening of RBCs had no measurable effect on their ability to traverse small channels. By contrast, a moderate decrease in the SA:V ratio had a marked effect on the equivalent cylinder diameter that is traversable by RBCs of similar cellular viscoelasticity. We developed a finite element model that provides a coherent rationale for the experimental observations, based on the nonlinear mechanical behaviour of the RBC membrane skeleton. We conclude that the SA:V ratio should be given more prominence in studies of RBC pathologies.  相似文献   
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