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1.
  • 1.1. Thrombocytes from mature rainbow trout (Sahmo gairdneri) aggregated in vitro after addition of ADP, ATP, collagen, epinephrine, 5-hydroxytryptamine or thrombin to thrombocyte-rich plasma.
  • 2.2. Thrombocyte aggregation was dose dependent and could be inhibited by preincubating the thrombocyte-rich plasma with adenosine, acetylsalicylic acid or prostaglandin E1.
  • 3.3. Thrombocytes released ADP and ATP when aggregated by 10 μM epinephrine. This release was blocked by 1 mM adenosine.
  • 4.4. Electron microscopic observations of thrombocytes revealed them to contain numerous microtubules and electron-dense vesicles. In addition a possible shape change associated with thrombocyte aggregation was noted.
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2.
  • 1.1. Two clotting factors, Cf-1(C) and Cf-2(C) were isolated from Agkistrodon acutus (collected in China) venom by gel filtration, ion-exchange chromatography and affinity chromatography. Using the same procedure, two clotting factors, Cf-1(T) and Cf-2(T), were isolated from Agkistrodon acutus (collected in Taiwan) venom and their characteristics were compared with Cf-1(C) and Cf-2(C).
  • 2.2. Molecular weights of Cf-1(C), Cf-2(C), Cf-1(T) and Cf-2(T) were determined to be 44,000, 70,000, 25,000 and 44,000 respectively. The factors were not immunologically related.
  • 3.3. The four clotting factors possessed tosyl-l-arginine methyl ester (TAME) hydrolyzing activity and coagulated fibrinogen to fibrin. Only Aα chain was cleaved when fibrinogen was incubated with each factor.
  • 4.4. Agkistrodon acutus is not classified by geographical location, however it is obvious that venom components vary between the Chinese and Taiwanese forms.
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3.
  • 1.1. In gaffkemic lobsters kept at 15°C. drastic declines in the hemocyte number and clotting ability occur.
  • 2.2. In animals kept at 10°C, although some clotting defects rapidly occur, a high number of amoebocytes is found. Clotting ability reappears after 5 days.
  • 3.3. The proportion of each type of hemocyte changes. Numerous hemocytes show morphologic altered features.
  • 4.4. Dorsal hematopoietic tissue is as in control lobsters.
  • 5.5. Total protein contents are similar in bacteremic or control lobster hemolymphs.
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4.
  • 1.1. Treatment of intact cultured H35 cells with trypsin (1 mg/ml) for 15 min at low temperature (4°C) or for 30 sec at 37°C causes activation of the insulin receptor subsequently isolated from the cells.
  • 2.2. Receptor activation was assessed by increased phosphotyrosine content of the β-subunit of the receptor, and increased autophosphorylation using [32P]-ATP.
  • 3.3. Treatment of the cells for 15 min at 37°C however completely abolished insulin binding and all insulin receptor kinase activity.
  • 4.4. These data demonstrate that proteolytic damage of the extracellular domain of the insulin receptor can render the receptor kinase inactive and lead to a cell which is unresponsive to insulin.
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5.
  • 1.1. The diffusional water permeability (Pd) of rabbit red blood cell (RBC) membrane has been monitored by a doping nuclear magnetic resonance (NMR) technique on control cells and following inhibition with p-chloromercuribenzene sulfonate (PCMBS).
  • 2.2. The values of Pd were around 6.3 × 10−3 cm/sec at 15°C, 7.0 × 10−3cm/sec at 20°C, 8.0 × 10−3 cm/sec at 25°C, 9.1 × 10−3 cm/sec at 30°C and10.7 × 10−3 cm/sec at 37°C.
  • 3.3. Systematic studies on the effects of PCMBS on water diffusion indicated that the maximal inhibition was reached in 15 min at 37°C with 0.5 mM PCMBS.
  • 4.4. The values of maximal inhibition were around 71–74% at all temperatures.
  • 5.5. The basal permeability to water was estimated as 1.6 × 10−3cm/sec at 15°C, 2.0 × 10−3cm/sec at 20°C, 2.4 × 10−3cm/sec at 25°C, 2.6 × 10−3cm/sec at 30°C, and 3.1× 10−3 cm/secat 37°C.
  • 6.6. The activation energy of water diffusion was around 18 kJ/mol and increased to 27 kcal/mol after incubation with PCMBS in conditions of maximal inhibition of water diffusion.
  • 7.7. The membrane polypeptide electrophoretic pattern of rabbit RBCs has been compared with its human counterpart.
  • 8.8. The rabbit membrane contained a higher amount of spectrin (bands 1 and 2), while the band 6 (glyceraldehyde-3-phosphate dehydrogenase) was markedly less intense.
  • 9.9. Considerable differences in the electrophoretic patterns of the two sources of RBC membranes appeared in the bands migrating in the band 4.5 region and in front of band 7, where some polypeptides were apparent in higher amounts in the rabbit RBC membrane.
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6.
  • 1.1. The effect of acclimation to 10° and 30°C on the blood volume, clotting time, total blood protein and numbers of cells was determined in Uca pugilator.
  • 2.2. There was no significant difference between blood volume in the 10° and 30° animals but there were significantly more cells and a higher blood protein in the 30° crabs.
  • 3.3. The clotting time is significantly longer for the 10° crabs.
  • 4.4. These changes associated with the blood parameters can be associated with the ecology of the animal.
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7.
  • 1.l. In gaffkemic lobsters kept at 15°C, the plasma coagulogen amount rapidly decreases and the gelation of hemolymph is prevented.
  • 2.2. In animals kept at 10°C, the available plasma coagulogen amount is always normal even when coagulation appears impaired or prevented.
  • 3.3. Extended clotting times as well as damaged coagulation cannot be correlated with coagulogen concentration.
  • 4.4. The site of synthesis of this factor is discussed.
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8.
  • 1.1. 3,3′,4,4′-Tetrachlorobiphenyl (TCB) was 20–100 times more toxic in chick embryos than in turkey embryos when injected into eggs.
  • 2.2. The ed50-value for induction of AHH activity by TCB in the liver of early chick and turkey embryos was estimated to be 0.6 and 6 μg/kg egg, respectively.
  • 3.3. In both species α-naphthoflavone was more effective than metyrapone at inhibiting basal and TCB-induced AHH activities.
  • 4.4. The TCDD receptor was detected in the liver of 7-day-old chick embryos, while it was not found in 9-day-old turkey embryo liver.
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9.
  • 1.1. Aerobic glucose disposal in starved oysters exposed to 1 mM external glucose was 2.29 μg C/g wet wt/min.
  • 2.2. It was hypothesized that the maximum disposal rate is limited by the maximum rate of transepithelial glucose transport.
  • 3.3. The major recipients of glucose-carbon were glycogen and amino acids. 4. The rate of glucose-carbon disposal to these two pools was 0.80 and 0.42 μg C/g/min, respectively.
  • 4.5. The internal energy state determines the pathways of glucose disposal.
  • 5.6. Disposal of glucose-carbon in “glucose-primed” oysters is primarily into glycogen.
  • 6.7. In fasted bivalves the disposal is primarily into amino acids and carboxylic acids.
  • 7.8. The uptake of dissolved glucose has the potential of contributing significantly to growth under conditions where the external glucose concentration is kept artificially high.
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10.
  • 1.1. Cat plasma prothrombin and partial thromboplastin times are faster than human. Thromboplastin generation tests are very similar.
  • 2.2. Factors VIII and V assay 24 and 13 times the human standard. Cat factors VII, X. IX, XI and XII assayed at 2.5 to 4 times human. Factors I, II and XIII fell within the human range and Fletcher was extremely low.
  • 3.3. One cat lacked factor XII and showed a prolonged APTT and clotting time.
  • 4.4. Cat profibrinolysin was activated by streptokinase but not by urokinase.
  • 5.5. Cat platelets aggregated with the usual human aggregation agents with the exception of thrombin and ristocetin.
  • 6.6. Cat erythrocytes were smaller and more numerous than human.
  • 7.7. Leukocyte counts were quite variable.
  • 8.8. Serum protein electrophoretic patterns differed from human in the greater migration of albumin and the presence of numerous unidentified bands.
  • 9.9. Biochemical tests showed high sodium and chloride values.
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11.
  • 1.1. Thermal stress, in vitro and in vivo, induced the synthesis of heat-shock proteins, HSP90, HSP70, and HSP23 in turkey leukocytes.
  • 2.2. HSP induction was both temperature- and time-dependent.
  • 3.3. Salinity-specific stress proteins were expressed with elevated osmolality in culture medium.
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12.
  • 1.1. The net absorption of protein, fatty acids, calcium and phosphate along the small intestine of the turkey (Meleagris gallopovo) was evaluated with the aid of 91Y as a reference substance.
  • 2.2. About 85% of the ingested protein was absorbed, with most of the absorption occurring in the duodenum and upper jejunum.
  • 3.3. The overall lipid absorption coefficient was around 90%, and was inversely related to the fatty acid chain length and saturation.
  • 4.4. Most of the lipid absorption occurred in the duodenum and jejunum.
  • 5.5. Calcium absorption also occurred in the duodenum and jejunum: its fractional rate decreased with calcium intake.
  • 6.6. Phosphate absorption occurred mostly in the duodenum and jejunum and its efficacy was only slightly affected by dietary phosphate intake.
  • 7.7. The high nutrient absorption in the turkey duodenum, relative to that of the chick (Gallus domesticus), was discussed.
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13.
  • 1.1. To evaluate changes in high-energy phosphate metabolism in the water scorpion (Ranatra chinensis) under restraint and cold water-warm water stresses, in vivo [31P]NMR spectra were obtained.
  • 2.2. Under restraint stress, arginine phosphate (Arg-P) decreased by 10% after 1 hr and remained at that level thereafter, while β-ATP showed negligible changes over 6 hr.
  • 3.3. As the water temperature gradually increased or decreased, the relative concentration of Arg-P decreased due to enzyme regulation.
  • 4.4. Repeated cold water-warm water stress, which consisted of repeated 15 min exposures to cold water (5°C) followed by 15 min exposures to warm water (30°C) caused distinct decreases in Arg-P and β-ATP concentration. These decreases were dependent on the frequency of exposure.
  • 5.5. Phosphomonoesters (PME) increased not only with restraint stress but also with cold water-warm water stress.
  • 6.6. The effect of cold water-warm water stress on high-energy phosphate metabolism was greater than that of restraint stress.
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14.
  • 1.1. Fundamental chitin digestion characteristics of Crassostrea virginica crystalline style were investigated.
  • 2.2. Optimum temperature and pH were 34°C and 4.8. respectively.
  • 3.3. The colloidal regenerated chitin (0.56mol/0.5 ml: GlcNAc equivalents) was saturating under all enzyme levels encountered.
  • 4.4. There was no evidence of end product inhibition, even after 100 hr incubation.
  • 5.5. Calculated Km for the chitinase complex was 1.19mM when determined using a 30 min assay, but was only 0.70 mM when determined using a 4.6 hr assay.
  • 6.6. Both Km values are lower than reported for similar assays in other molluscs and for most bacteria.
  • 7.7. Effect of substrate preparation on the kinetics are discussed.
  • 8.8. Eight peaks of chitinase activity were resolved by DEAE-Fractogel ion exchange chromatography.
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15.
  • 1.1. The flow of pancreatic juice and its composition of protein, amylase, trypsin and chymotrypsin were measured in sheep during treatments known to induce a response in nonruminants.
  • 2.2. Intraduodenal peptone (100 or 200 μg/min) had no affect but intraduodenal hydrochloric acid (66 μequiv/min) or intravenous (iv) pentagastrin (10 μg/min) doubled the flow and enzyme output. Cholecystokinin (1.0 IDU/min iv) caused smaller changes in enzyme output but no change in flow, whereas, secretin (0.5 or 1.0 CU/min iv) caused a rapid, sustained, five- or six-fold increased in flow but only a transitory increase in enzyme output.
  • 3.3. The largest increases in enzyme output occurred during stimulation of the vagus (10 Hz, 10 V); the outputs were sustained at 5–10 times control levels and the flow increased two- or three-fold.
  • 4.4. A non-parallel response of amylase, trypsin and chymotrypsin occurred during administration of those treatments which significantly enhanced the enzyme output. Compared with periods of basal secretion the stimulated juice contained significantly more chymotrypsin and amylase than trypsin; the relationship between chymotrypsin and amylase did not change significantly.
  • 5.5. The composition of the juice during stimulation approached and often equalled the enzyme composition of pancreatic tissue.
  • 6.6. These results are compatible with the view that the mixture of enzymes in pancreatic juice is derived from at least two compartments with different enzyme compositions.
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16.
  • 1.1. Embryonic and posthatch turkey skeletal muscle development was compared in in vitro studies using clonal-derived embryonic myoblasts and satellite cells.
  • 2.2. Although population doubling times were similar between the two lines (25.4 hr for satellite cells and 26.4 hr for embryonic myoblasts), embryonic myoblasts consistently began log phase growth 24 hr earlier than satellite cells.
  • 3.3. Differentiation (fusion) of embryonic myoblasts was maximized by 36 hr in Dulbecco's Modified Eagle's Medium containing 1% horse serum compared with 72 hr for satellite cells.
  • 4.4. When administered a serum-free medium which supports proliferation of turkey satellite cells, embryonic myoblasts differentiated to form myotubes.
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17.
  • 1.1. Estimates of extracellular phase volume and cellular electrolyte concentrations based on [14C] PEG-4000, chloride, chloride/potassium and sodium spaces were compared at three epaxial muscle sites and in cardiac muscle, liver, gut, spleen and brain samples of rainbow trout.
  • 2.2. [14C] PEG-4000 appeared to provide realistic estimates of tissue water distribution and cellular ion levels in brain and is suitable for use with epaxial and cardiac muscle, gut and spleen but not liver.
  • 3.3. [14C] PEG-4000, chloride and chloride/potassium spaces were comparable in epaxial muscle, cardiac muscle and gut. Thus, no advantage is associated with use of the former rather than ion-defined estimates of extracellular phase volume in these tissues.
  • 4.4. [14C]PEG-4000 and sodium spaces appear to be preferable to chloride and chloride/potassium spaces as indicators of tissue water distribution in spleen.
  • 5.5. Sodium provides unrealistic estimates of extracellular phase volume in tissues other than spleen and liver.
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18.
  • 1.1. Using a high-speed video system operating at 400 frames/sec, the effects of temperature on tail beat frequency, swimming speed and stride length were examined in newly hatched larvae of herring (Clupea harengus L.) and in tadpole larvae of the ascidian Dendrodoa grossularia van Beneden.
  • 2.2. The effect of temperature was linear; the tail beat frequency of 8 mm-long herring larvae increased from 19 Hz at 5.6°C to 37 Hz at 14.9°C (Q10 = 2.04); that of 2 mm-long Dendrodoa larvae increased from 10 Hz at 9.6°C to 23 Hz at 18.1°C (Q10 = 2.52).
  • 3.3. Burst swimming speeds of herring larvae increased from 80 mm/sec at 5°C to 150 mm/sec at 15°C, stride length remaining constant at about 0.5 of the body length for each tail beat.
  • 4.4. More continuous swimming of Dendrodoa increased from 4.0 mm/sec at 10°C to 11.5 mm/sec at 18°C, the stride length increasing from about 0.15 to 0.25.
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19.
  • 1.1. Post-feeding hypoglycemia, an unknown phenomenon in wild raptors, was studied in a central nervous system (CNS) damaged American kestrel, Falco sparverius Linnaeus.
  • 2.2. Beef chunk ingestion (200 g/kg BW) produced symptomatic hypoglycemia (45–60 min) which was accompanied by prolonged decreases (240 min) in plasma glucose and increased plasma levels (60 min) of an immunoreactive component (IC) believed to be insulin.
  • 3.3. Beef chunk-induced hypoglycemia and increases in plasma IC levels were blocked by atropine (0.02 mg/kg) pre-treatment.
  • 4.4. Oral glucose loading (1 g/kg) also produced symptomatic hypoglycemia (30–40 min), but of shorter duration (90 min), with corresponding changes in plasma glucose and 1C levels but these responses were not blocked by atropine.
  • 5.5. Data suggest that insulin secretion was stimulated via indirect (vagal) and direct (blood glucose) routes and that post-feeding hypoglycemia resulted primarily from deranged CNS-associated mechanisms (hypothalamic, possibly pituitary) which control catabolic hormone release, endogenous glucose production and consequently, plasma glucose levels.
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20.
  • 1.1. Brain trehalase specific activity and trehalosemia were measured during the end of the developmental life cycle in non-diapausing and diapausing insects.
  • 2.2. During non-diapausing development, trehalosemia reached maximum values at the beginning of pupal life. Then a constant decrease was observed up to the end of adult life.
  • 3.3. The specific activity of brain trehalase was maximum when the insects were in active feeding periods, minimum activity appearing during moulting phases.
  • 4.4. During diapausing development, trehalosemia was very high at the beginning of pupal life, particularly when insects were exposed to wintering conditions.
  • 5.5. When diapause was broken, trehalosemia fell, announcing adult emergence.
  • 6.6. Brain trehalase activity showed the same qualitative variations as in non-diapausing larvae, but with rather lower values.
  • 7.7. During pupal life, brain trehalase activity decreased markedly during the long period necessary to obtain diapause breakdown.
  • 8.8. Wintering conditions allow a progressive increase of brain trehalase activity, which preceded the fall of trehalosemia.
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