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1.
  • 1.1. The effects of seasonal variation on the carbohydrate and lipid metabolism of the Chasmagnathus granulata were investigated.
  • 2.2. Glycemia is high in winter and summer and low in spring and fall.
  • 3.3. The glycogen content in the hepatopancreas and muscle is higher in fall and winter, and decreases during spring and summer.
  • 4.4. The muscle lipids are higher in summer, and decrease during fall and winter whereas hepatopancreas lipids are higher except in the fall.
  • 5.5. The crabs show change in the metabolic pattern of lipids and carbohydrates during the seasons of the year.
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2.
  • 1.1. Seasonal acclimatization effects on oxygen consumption, body temperature, and body weight were evaluated in three different experimental groups of Dipodomys panamintinus.
  • 2.2. Body weights of wild field as well as captive animals housed in outdoor sand cages were maximum in winter and lowest in summer for both sexes.
  • 3.3. Mean oxygen consumption was maximum in winter and lowest during spring in both sexes of the wild field and captive exposed groups.
  • 4.4. Neither weight nor oxygen consumption of indoor control animals varied with the seasons.
  • 5.5. No significant differences in body temperatures were observed during either the fall or winter seasons.
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3.
  • 1.1. Since glucose is one of the main energetic substrates for general metabolic processes in crustaceans, analysis of carbohydrate levels can furnish information on the energy metabolism of intact animals during osmoregulation.
  • 2.2. Different groups of Chasmagnathus granulata were transferred to different salinities (0 and 40%), and the glucose and glycogen concentrations in blood, gills, muscle and hepatopancreas were determined at the beginning of the experiment and 24, 72, 168 and 360 hr after the salinity changes.
  • 3.3. Differences in tissues carbohydrate levels were observed between summer and winter, that reflected differences in reserve mobilization.
  • 4.4. In the summer, hypo- and hyperosmotic shocks induced an increase in carbohydrate levels in almost all tissues studied, indicating gluconeogenesis.
  • 5.5. In the winter, a carbohydrate mobilization occurred only in the gills and hepatopancreas after both osmotic shocks.
  • 6.6. Thus, the substrate reserve used for energy production required for osmoregulation seems to be dependent on the season and tissues.
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4.
  • 1.1. Seasonal variation in total lipids was examined in several body components of the turtle Sternotherus odoratus.
  • 2.2. Carcass fat stores in both sexes were depleted during winter. Additionally, a decline in carcass lipids was associated with increases in gonadal mass.
  • 3.3. Concentrations of liver lipids were maximal during August and minimal during winter.
  • 4.4. Males showed little seasonal change in plasma lipid levels, whereas females had seasonal peaks temporally associated with ovarian development and carcass fat storage.
  • 5.5. Ovarian concentrations of lipids were minimal after nesting and increased during fall.
  • 6.6. Results suggest that S. odoratus uses stored fats both for reproduction and maintenance during winter.
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5.
  • 1.1. The extent of anaerobic energy production of Arenicola marina during low tide is dependent on the season and on the locality in the intertidal.
  • 2.2. Anaerobic energy production was only found: (a) in animals from sediments, which fall dry for several hours; (b) in summer and autumn, but not in winter and spring.
  • 3.3. A correlation between the extent of anaerobic energy production and the development of gametes was demonstrated.
  • 4.4. The process of spawning represents a great stress to the animals. At this time the ability of Arenicola marina to survive anaerobic conditions was reduced drastically.
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6.
  • 1.1. S. prophetarum uses during the aestivation periods of summer and winter only 33% and 22%, respectively, of the total organic storage content, even though the summer aestivation period is much longer.
  • 2.2. During the long summer aestivation period the snails use a small amount, 0.2% per day, of the different organic storage materials.
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7.
  • 1.1. Properties of acetylcholinesterase (AChE, EC 3.1.1.7) from Apis mellifera head were studied during pupal development and at the adult stage.
  • 2.2. During post-embryonic development, tissue and specific activities were closely related and increased to reach a maximum value at emergence and at last pupal stage, respectively.
  • 3.3. In adults, AChE activity was weaker in foragers than in emerging bees.
  • 4.4. The membrane form occurred in adult bees as well as in pupae whereas the soluble enzyme only appeared from Pd pupal stage.
  • 5.5. The proportion of soluble and membrane forms fluctuated during late development but, in all cases, the percentage of the soluble form remained less than 10% of total AChE activity.
  • 6.6. At all post-embryonic stages, the membrane form was sensitive to the action of phosphatidylinositol-specific phospholipase C (PI-PLC) and was converted into a hydrophilic enzyme.
  • 7.7. In adult bees, the sensitivity to PI-PLC depended on the season. In summer, about 60% of the membrane activity could be solubilized by PI-PLC vs only 5% in winter.
  • 8.8. The sensitivity of AChE to pirimicarb varied with the developmental stage.
  • 9.9. In foraging bees, AChE was more susceptible to pirimicarb than in emerging bees. This difference of sensitivity to carbamate was abolished after removal of the membrane anchor either by mild trypsin digestion of PI-PLC treatment.
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8.
  • 1.1. Metabolic rates were highest during periods of maximum reproduction.
  • 2.2. The exponent of the metabolic rate-weight equation varied seasonally, rates of metabolism of small animals exhibited greater annual fluctuations than those of large animals.
  • 3.3. Absolute and weight-specific Q10s (determined at 5–10°C above field temperatures) for smaller clams were greatest in the winter; absolute values of Q10 were highest for larger individuals in the summer.
  • 4.4. Small clams had Q10 < 1.0 in the summer; Q10-values for larger clams were near 1.0 at this time.
  • 5.5. 38.9% of the total energy assimilated by the population annually was allocated to metabolism, which is near the low end of the range of values reported for freshwater molluscs, suggesting that this species can partition a large amount of energy to growth and reproduction.
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9.
  • 1.1. Seasonal changes in the accumulation of end products after 48 hr of exposure to air and in the composition of the free amino acid pool were studied in Mytilus edulis.
  • 2.2. The accumulation levels of succinate and acetate showed only weak seasonal changes.
  • 3.3. Conversion of succinate to propionate was high in summer and virtually zero in winter
  • 4.4. Alanine and most other free amino acids were present in relatively high concentrations in summer and early autumn and reached minimal values in winter and early spring.
  • 5.5. Exceptions were glutamate, aspartate and taurine, which showed hardly an season related changes and glycine, which changed inversely to the majority of the free amino acids.
  • 6.6. The anaerobic formation of alanine was inversely proportional to the endogenous concentration.
  • 7.7. The only other free amino acids affected by anaerobiosis were glutamate and aspartate, which respectively increased and decreased under these conditions.
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10.
  • 1.1.|Resting metabolic rate of laboratory rabbits kept indoors is susceptible to seasonal fluctuations and is higher in winter than in summer.
  • 2.2.|Thermoneutral zone of rabbits under these conditions may shift downwards in winter and upwards in summer.
  • 3.3.|Both of these adjustments in thermoregulation seem to be related to the seasonally changing photoperiod.
  • 4.4.|Dehydration does not influence these thermoregulatory adaptive changes.
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11.
  • 1.1. Thirty-one male golden-mantled ground squirrels were divided into four physiological groups: low wt summer, medium wt summer, high wt summer and hibernation period. A second group of 10 females was divided into two groups: hibernation period at low Tb and hibernation period during a periodic arousal.
  • 2.2. Blood serum, pancreas and antral stomach region were collected from each animal.
  • 3.3. The serum was analysed by radioimmunoassay for pancreatic polypeptide immunoreactivity, the pancreas for pancreatic polypeptide and somatostatin immunoreactivity and the antral region of the stomach for gastrin immunoreactivity.
  • 4.4. Significant between-stage differences (P < 0.05) were found in serum pancreatic polypeptide concentration and in pancreatic somatostatin content.
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12.
  • 1.1. Seasonal changes of circulating blood parameters of Natrix n. natrix were evident and involved both sexes to the same extent.
  • 2.2. A significant decrease in red cell count, haematocrit and haemaglobin concentration in the mating period, and an increase in those parameters and mean cell volume in autumn were observed, and haemodilution during winter torpor.
  • 3.3. The changes during the breeding season had probably a hormonal background; in winter, they resulted first of all from a decreased erythropoietic activity and, to a lesser extent, from an increased red blood cell breakdown rate. However, the possibility that some erythrocytes were withdrawn from the circulation cannot be excluded.
  • 4.4. Winter lymphocytopenia, eosinocytopenia and neutrophilic granulocytosis in females during egg laying were expressions of changes of leucocyte formula.
  • 5.5. Seasonal cyclicity was found only with respect to the white cell count in males and the eosinophile fraction in males and females.
  • 6.6. Probable reasons for, and mechanisms of the changes in blood composition are discussed.
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13.
  • (1)The preferred temperatures of Macrobrachium acanthurus were determined for prawns acclimated to 20°C, 23°C, 26°C, 29°C and 32°C, and the final preferendum estimate was (29.5°C).
  • (2)The critical thermal minima (CTMin) and maxima (CTMax) were 11.0°C, 12.1°C, 13.0°C and 14.8°C, and 34.2°C, 35.0°C, 36.1°C and 39.8°C, respectively.
  • (3)The zone of thermal tolerance assessed using the CTMin and CTMax boundaries was 644°C2.
  • (4)The acclimation response ratio was between 0.33 and 0.62.
  • (5)To cultivate this species in the southeastern region of México it should be done in not <15°C (CTMin) during the winter and below 38°C in summer (CTMax).
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14.
  • 1.1. Lipid, glucose and glycogen concentrations were measured in different tissues of the crab Chasmagnathus granulata during emersion.
  • 2.2. After 6 hr of emersion no reduction in the total amount of carbohydrates was found to occur, suggesting that a general metabolic arrest was taking place.
  • 3.3. A transitory increase in haemolymphatic glucose and lipid levels was observed. Possible causes are therefore discussed in relation to changes in the flux of substrates for energy production.
  • 4.4. The mobilization of carbohydrates and lipids to the gills, observed only during summer, may be concerned with energy supplying for ionic regulation.
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15.
  • 1.1. In the present work we have studied different aspects of the phagocytic process in peripheral blood granulocytes from the turtle Mauremys caspica: (a) tissue adherence capacity, (b) spontaneous mobility and chemotaxis, (c) attachment and ingestion of foreign cells (Candida albicans) or inert particles (latex beads), and (d) capacity to digest ingested material measured by nitroblue tetrazolium (NBT) reduction. These studies were carried out in vitro at 37°C in autumn, winter, spring and summer.
  • 2.2. The adherence index showed significantly higher values in autumn, and smaller values in winter. The spontaneous mobility was not affected seasonally, but the chemotaxis was significantly increased in winter and decreased in autumn. The numbers of C. albicans attached and ingested as well as latex beads ingested per 100 granulocytes were higher in autumn and summer, and lower in winter and spring. The digestion capacity was greatly decreased in summer.
  • 3.3. The comparison between the results obtained here and those found using the same techniques in blood human granulocytes showed that these animals are endowed with an adequate phagocytic response.
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16.
 
  • 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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17.
  • 1.1. Body weight, the weight of the hepatopancreas, protein content in the hepatopancreas and phosphatase activity at pH 8.5 in the hepatopancreas are great in spring and summer, and decrease during autumn and winter.
  • 2.2. Phosphatase activity at pH4.5 is the same throughout the year.
  • 3.3. Participation of acid phosphatases in extracellular and intracellular digestion and participation of alkaline phosphatases in food resorption and calcium deposition are postulated.
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18.
  • 1.1. Blood parameters determining oxygen capacity and oxygen affinity were measured in brown trout at different times of the year.
  • 2.2. Haematological data indicate a slight decrease in blood oxygen capacity during the warm seasons. 3. Oxygen affinity increases significantly during summer and decreases in winter.
  • 3.4. The changes in P50 exhibited a positive correlation with the amount of anodic haemoglobin components, and a negative correlation with the amount of cathodic haemoglobin components.
  • 4.5. The changes observed in the [ATP]/[Hb] molar ratio were not correlated with oxygen affinity and gave values near one.
  • 5.6. We conclude that the oxygen affinity increase could be a physiological adaptation to oxygen transport during the wanner period. A possible mechanism is discussed.
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19.
  • 1.1. Seasonal changes in 14C- and 3H-labelled glucose metabolism were studied in an in vitro preparation of the mantle tissue from Mytilus edulis L. throughout 1978–1979.
  • 2.2. Incorporation of [1-14C] and [6-14C]glucose into glycogen and amino acids peaked in the summer, resulting in an increased rate of glucose utilisation. [2-3H]glucose utilisation data agreed with this finding.
  • 3.3. Pentose phosphate pathway activity reached a maximum in the spring of 1979, but represented only a very small fraction of the total glucose utilisation.
  • 4.4. In the winter, and during starvation experiments, the capacity for exogenous glucose utilisation fell, with a compensatory increase in tissue glycogen degradation. The contribution of the Embden-Meyerhof pathway to total carbohydrate metabolism appeared to remain stable throughout the year.
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20.
  • 1.1. Digestive gland and mantle fatty acids were studied in spring and summer in the bivalve Macoma balthica off the southern coast of Finland. The presence of lipids was also examined histochemically in various clam tissues.
  • 2.2. the neutral lipid content of the digestive gland increased ca 4.5-fold during the annual growth period.
  • 3.3. Neutral lipid fatty acids of the digestive gland, of which palmitoleic, eicosapentaenoic and palmitic acids were predominant, were clearly distinguished from phospho- and glycolipid fatty acids.
  • 4.4. The degree of unsaturation of phospholipid fatty acids was higher in the cold season both in the digestive gland and mantle, mainly due to the titer of eicosapentaenoic acid.
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