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1.
  • 1.1. The total loss of potassium during the stepping cycles executed by the tube feet of starfish has been estimated.
  • 2.2. The oxygen requirement necessary to operate an ion pump to replenish this loss has been shown to represent only a small percentage of the total consumption.
  • 3.3. The demands of ionic regulation are unlikely to be a limiting factor in animals entering water of reduced salinity.
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2.
  • 1.1. l-Leucine transport by everted slices of duodenum, jejunum ileum and cecum of 1-, 2- and 3-week-old chickens has been determined.
  • 2.2. The effects of the administration with the diet of three anticoccidial drugs: monensin, maduromicin ammonium and nicarbazine have been studied.
  • 3.3. In the control animals, there is a reduction on intestinal transport with age, except in the duodenum which is not age-dependent.
  • 4.4. Momensine induces an increase on leucine transport in the duodenum and cecum at all ages studied and only in the 3-week-old animals in the jejunum and ileum.
  • 5.5. Nicarbazine reduces jejunal absorption of leucine and does not affect the function of the other segments.
  • 6.6. Maduromicin ammonium has almost no effect on the absorptive process.
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3.
  • 1.1. Weight change after submerging the earthworm into water varied remarkably according to the environmental humidity in which animals were placed before submergence.
  • 2.2. Pretreatment with physiological saline solution before submergence in water gave stable values for the ionic concentrations of the body fluid.
  • 3.3. Brain removal caused decrease of both sodium and chloride ion concentrations and increase of potassium ion concentration of the coelomic fluid when animals were submerged in water.
  • 4.4. Although brain replacement failed, action of a brain hormone is suggested to regulate the decrease of both sodium and choride ions and increase of potassium ion of the coelomic fluid to normal level when animals were submerged in water.
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4.
  • 1.1. The levels of non-esterified fatty acids (NEFA) in the plasma of a variety of animals have been estimated.
  • 2.2. Only one of seven elasmobranchs contained detectable levels of NEFA.
  • 3.3. The two crustaceans examined contained very low levels.
  • 4.4. All the other animals contained circulating levels of a variety of NEFA ranging from 14 to 24 carbon atoms.
  • 5.5. The elasmobranchs are unique in that they also do not possess proteins in the serum which bind fatty acids.
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5.
  • 1.1. A quick and simple procedure is described for purifying kallikrein from human whole saliva. The enzyme has been purified about 2700-fold with a yield of approx. 30%.
  • 2.2. The procedure is based on the immediate fractionation of saliva by ion exchange chromatography. This is followed by a combination of affinity and high performance liquid chromatography.
  • 3.3. The results indicate that another protein component binds to the enzyme at pH 8.0.
  • 4.4. The homogeneity of the enzyme has been demonstrated by gel electrophoresis in the absence as well as in the presence of sodium dodecylsulfate.
  • 5.5. A mol. wt of 40,100±1800 has been calculated from gel electrophores is experiments.
  • 6.6. Sedimentation equilibrium in an analytical ultracentrifuge gave a mol. wt of 39,700.
  • 7.7. The amino acid composition has been determined and it confirms that the enzyme has a low isoelectric point.
  • 8.8. The presence of tryptophan has been demonstrated by absorption and fluorescence spectroscopy.
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6.
  • 1.1. Three DNA dependent RNA polymerases have been purified from chromatin and chloroplast fractions of wheat leaves.
  • 2.2. The purified enzymes were completely dependent on exogenous DNA after purification by glycerol gradient, DEAE-Sephadex and phosphocellulose chromatography.
  • 3.3. The nuclear enzymes, I and II, showed a strong preference for denatured nuclear DNA, whereas the chloroplast enzyme preferred denatured chloroplast DNA.
  • 4.4. The three enzymes require either Mg2+ or Mn2+ for activity.
  • 5.5. α-amanitin specifically inhibited RNA polymerase II but has no effect on polymerase I and chloroplast polymerase.
  • 6.6. Enzyme I is most active at very low ionic strength (0.10 mM KC1), whereas enzyme II and chloroplast enzyme show maximum activity at 150mM and 50 mM KC1 respectively.
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7.
  • 1.1. The effect of 4 concentrations of 6 various thromboplastins (TRPL) on plasmas of man, 7 mammalian and 2 avian species was investigated.
  • 2.2. Every plasma was clotted in shortest time by the homologous TRPL.
  • 3.3. Plasmas of near related animals exhibited no difference when tested with TRPLs of these animals.
  • 4.4. Plasmas with high factor VII levels were clotted in a short time.
  • 5.5. In rodents the clotting time of plasmas seemed to be partially dependent on the factor VII levels.
  • 6.6. A given TRPL did not always clot the homologous plasma in the shortest time.
  • 7.7. The possible role of factor VII in homo- and heterologous test system is discussed.
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8.
 
  • 1.The levels of water, Na, K, Ca and Mg in blood serum, brain and kidney and aldosterone level in blood of Naja haje haje were studied during the different phases of the annual cycle.
  • 2.The water content in the tissues studied displayed only minor changes as the animals passed from one phase to the other.
  • 3.A significant increase in Na was recorded in the brain during the different phases indicating a depressed sodium pump, whereas the blood Na level showed a significant decrease during hibernation.
  • 4.K increased in blood serum, brain and kidney during hibernation, while a nonsignificant decrease was found in blood serum during arousal. The brain may act as a potassium reservoir.
  • 5.An increase in Ca and Mg concentration was recorded in blood serum, brain and kidney during prehibernation and hibernation. The data suggested a homeostatic function in the transport and metabolism of these cations.
  • 6.Aldosterone exhibited a highly significant decrease especially during hibernation. The aldosterone regulation of ionic composition is discussed.
  • 7.Na/K and Ca/Mg ratios in the brain may explain the decreased excitability during winter torpor.
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9.
  • 1.1. A variety of haematological parameters were determined in adult Dasyurus viverrinus.
  • 2.2. Haemoglobin and red cell counts were high with a very low mean cell volume.
  • 3.3. Basophils are absent but the eosinophils contain small numbers of basophilic granules which may indicate a dual role for this cell.
  • 4.4. “Ring Form” leucocytes are present.
  • 5.5. Three types of red cell picture could be identified, some animals showing large numbers of spherocytes, spicule cells, and inclusion bodies.
  • 6.6. These cells resemble those found in some inherited human haemolytic anaemias but there was no evidence of haemolysis in the animals.
  • 7.7. An alkali resistant haemoglobin component is present.
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10.
  • 1.1. The influence of temperature (14,19, 24°C), salinity (26,32, 38,44%.) and food type (artificial diets: Fryfood, Mytilus, Soya, Yeast, Spirulina) on the respiratory rate of Tisbe holothuriae has been studied.
  • 2.2. Oxygen consumption decreased with decreasing temperature, but with a greater rate at supra- or subnormal salinities.
  • 3.3. Multiple-regression analysis showed the quadratic effect of temperature and the linear effect of salinity to be the more important factors affecting respiration.
  • 4.4. The food type also seems to exert an important effect on oxygen consumption.
  • 5.5. A significant lowering of respiration was observed for all food tested when the animals were starved.
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11.
  • 1.1. Changes in urine and plasma concentrations (sodium, potassium, magnesium, calcium and total osmotic) and urine production were determined in fish exposed to various concentrations of an ionically active substance, sodium chloride, and a non-electrolyte, mannitol, as well as freshwater.
  • 2.2. Responses occurred for the most part over a short crisis period preceeding establishment of new stable conditions.
  • 3.3. It was shown that plasma homeostasis was not maintained in response to changing ion-osmotic and osmotic gradients.
  • 4.4. Urinary osmotic and ionic concentrations were unaffected and urine production was shown to be inversely related to the external concentration.
  • 5.5. It is suggested that ionic shifts between body compartments are an important aspect of ion-osmotic adaptation.
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12.
  • 1.1. Neonatal mice received subcutaneous injections of buffer, thiourea (TU) or propylthiouracil (PTU).
  • 2.2. The PTU-treated mice were sacrificed on postnatal day 14 (P14) and the TU-treated mice on P28.
  • 3.3. Brain weights of the TU- and PTU-treated mice were not significantly different from the controls.
  • 4.4. Acid but not alkaline phosphatase activity in the braistem decreased after TU and PTU treatment.
  • 5.5. Myelination as indicated by intensity of luxol fast blue staining was weaker in drug-treated animals.
  • 6.6. The level of myelin marker enzyme, 2′,3′-cyclic nucleotide 3′-phosphohydrolase, was lower in the brainstem of PTU-treated animals.
  • 7.7. The results suggest a correlation between acid phosphatase but not alkaline phosphatase activity with myelination in the developing mouse brain.
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13.
  • 1.1. The regulation of ions at similar concentrations in most individuals of a species suggests the existence of internal reference standards.
  • 2.2. Few have been identified, but many probably relate to cell membrane properties, including potentials, surface charge densities and equilibrium constants of receptor molecules.
  • 3.3. Solubility may sometimes determine the product [Ca2+][CO32−].
  • 4.4. Reference standards must generally each relate to more than one ionic species.
  • 5.5. For some concentrations, including osmolality, there may be no direct reference standard.
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14.
  • 1.1. Homeostasis, or the maintenance of a constant internal environment, in invertebrate organisms decreases the dependence of these organisms on the vagaries of the external environment.
  • 2.2. The evolution of physiological processes influencing homeostatic conditions begins with the organism being totally dependent upon the external environment, passing through a series of intermediate stages during which fluctuation in a given internal parameter occur, proceeding finally to a condition where the internal environment is constant and independent of the external environment.
  • 3.3. A hypothetical scheme for the possible evolutionary pathway of osmotic and ionic regulation in aquatic invertebrates was developed in an attempt to follow the process of homeostasis in these organisms.
  • 4.4. Primitive marine cells developed mechanisms to regulate the ionic composition of the cytoplasm probably in association with the need for volume regulation.
  • 5.5. The development of a body wall separated an internal body fluid from the external sea-water and the ionic composition of the body fluids was initially maintained slightly different from that of the sea-water by essentially passive means.
  • 6.6. The addition of excretory organs, which arose initially through an inpushing of the body wall, brought about the ability for osmoregulation.
  • 7.7. Homeostatic mechanisms must be in place before an organism can move from one environment to another.
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15.
  • 1.1. Urate spherules obtained from three cockroach species have been isolated, purified and examined by scanning electron microscopy, atomic absorption, i.r. and Kjeldahl analysis.
  • 2.2. Purified spherules exposed to ionic environments may change from a smooth to a textured form.
  • 3.3. Ion analysis confirmed that the spherules are high in K+ and low in Na+.
  • 4.4. All preparations from the cockroach tissues diaplayed similar i.r. spectra, but were dissimilar to those of uric acid and urate salt standards.
  • 5.5. It appears that there is a distinct pattern or mechanism by which the cockroach urates are deposited in the spherule matrix.
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16.
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17.
  • 1.1. Aspartate aminotransferase activity in the white muscle of rainbow trout dropped significantly after the animals had received a pyridoxine-deficient diet for 7 days.
  • 2.2. Alanine aminotransferase activity in the white muscle of rainbow trout dropped significantly after the animals had been fed on a pyridoxine-deficient diet for 21 days.
  • 3.3. Alanine and aspartate aminotransferase activity in the liver of rainbow trout did not drop significantly until the animals had received a pyridoxine-deficient diet for 28 days.
  • 4.4. After rainbow trout have received a pyridoxine-deficient diet for 35 days, feeding with complete diet for 7 days is sufficient to restore the aminotransferase activities to the levels observed in control animals.
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18.
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19.
  • 1.1. The lipid components of three animals, the rock crab Nectocarcinus integrifons, the rock flathead Platycephalus laevigatus and the southern garfish Hyporhamphus melanochir, feeding in the seagrass beds at Corner Inlet, Victoria, Australia have been examined in detail in order to provide further information on seagrass community structure.
  • 2.2. Biological marker compounds detected within animal gut content material were used to recognize dietary sources and then utilized by community members.
  • 3.3. Both H. melanochir and N. integrifons have been shown to ingest and to varying degrees incorporate seagrass lipid material, thus further confirming the importance of seagrass carbon in the Corner Inlet environment.
  • 4.4. The southern sea garfish H. melanochir is observed to remove C18 PUFAs (polyunsaturated fatty acids) from ingested seagrass material.
  • 5.5. Seagrass sterols are altered during incorporation into the lipids of this fish.
  • 6.6. Lipid-rich digestive juices play a role in the digestive processes of all three animals.
  • 7.7. Components tentatively identified as (NMI) (non-methylene interrupted) fatty acids have been detected in the lipids of the garfish H. melanochir and the crab N. integrifons.
  • 8.8. The fecal material of all three animals represent possible sources of these lipids (NMI acids) in Corner Inlet sediments.
  • 9.9. Based on lipid compositional data, N. integrifons feeds on Posidonia australis detritus and associated epiphyte material.
  • 10.10. The removal of both plant and epibiota cellular lipids along the digestive tract of the crab was observed, although structural components such as long chain mono- and α,ω-dicarboxylic acids, which have been previously recognized as seagrass marker lipids are not directly absorbed.
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20.
  • 1.1. Glycerinated stalks of Vorricella convallaria may be induced to contract by the application of either Ca2+ or Mg2+, and the contractions vary complexly as a function of pH.
  • 2.2. The coiling that occurs in the presence of Mg2+ is atypical, and the effect of ionic strength is to prevent coiling.
  • 3.3. The Ca2+ -contractions are typical of living vorticellid coiling, and those occurring at pH 6.8 and 7.0 are inhibited at low ionic strength and enhanced at high ionic strength.
  • 4.4. High concentrations of Ca2+ abolish the ionic strength repression of contraction.
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