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1.
- 1.1. Water vapour conductance (GH2O) was determined for 25 grey heron Ardea cinerea eggs in the laboratory, and in nests during natural incubation at two Scottish colonies.
- 2.2. The mean GH2O of eggs measured in the nest which successfully hatched was 9.0 mgH;O/mmHg/day and the mean water vapour pressure gradient between egg and nest (ΔPH2O), measured using “calibrated” duck eggs, averaged at 31 mmHg (4.13 kPa).
- 3.3. Based on eggshell porosity results, from the eggs which hatched, such a gradient would result in a loss of water from the eggs during incubation equivalent to 11% of their fresh weight.
- 4.4. Shell thickness, the number of pores/cm2 of eggshell and DDE content were also determined for the 25 eggs measured in the laboratory.
- 5.5. Eggs containing high levels of DDE had thinner shells, more pores in the eggshell and a higher overall eggshell porosity.
- 6.6. The main problem posed by a high level of DDE would appear, however, not to be an excessive water loss from the egg during incubation, but rather eggshell thinning leading to a loss of the egg due to breakage in the nest.
2.
《Comparative biochemistry and physiology. A, Comparative physiology》1983,74(2):289-293
- 1.1. 14C-dichlorofarnesoate permeated rapidly into Haemonchus contortus (infective juveniles) and Panagrellus redivivus (mixed cultures) and was strongly bound by hydrophobic association (Ks > 10−4M).
- 2.2. Uptake rose linearly with increases in temperature (5–38°C) and external concentration (C0; 0.07–2.15 × 10−4 M). Within 1 hr the internal concentration, C1 was >C C0.
- 3.3. The pH of the medium (6–8) did not affect uptake.
- 4.4. Efflux of dichlorofarnesoate was low: the half-time of release was > 18 hr.
- 5.5. The uptake curve approximated to the expression C1/C0 = a(1 − e−bt) with a and b as constants and t in hr.
- 6.6. These results clarify previous work on the inhibitory action of juvenile hormone on the development of nematodes.
3.
《Comparative biochemistry and physiology. A, Comparative physiology》1993,104(2):367-371
- 1.1.Juvenile Japanese eels (Anguilla japonica) were fed on a diet supplemented with estradiol-17β (E2) at doses of 25, 50 and 75 mg/kg. The effects on growth, sex distribution and body composition were investigated in two groups of gonadally undifferentiated stages (early and later juvenile stages).
- 2.2.Feminization (95–100%) was observed in all E2-treated groups.
- 3.3.The growth rate of fish treated with 25 and 50 mg/kg E2 diet at the early juvenile stage was significantly increased.
- 4.4.The amount of protein in muscle decreased and that of fat increased in the E2-treated groups except in the early juvenile stage fed with 25 mg/kg E2.
4.
《Comparative biochemistry and physiology. A, Comparative physiology》1993,104(2):381-384
- 1.1. Slow-growing juvenile Nile crocodiles were injected with recombinant bovine growth hormone (rbGH) once a week for 6 weeks and then re-treated after 4 weeks.
- 2.2. The feed intake of the treated crocodiles was 26 g/kg/meal during the three periods, while the intakes of the controls were 15, 20 and 2 g/kg.
- 3.3. The treated gained 2.3 and 0.9%/week in weight during the first and second injection period and the feed conversion efficiencies were 28 and 13%. The controls lost weight.
- 4.4. The treated animals grew at rates of 0.98 and 0.43%/week during the first and the second injection period.
- 5.5. Bovine GH enhances growth in juvenile crocodiles and seems to have less adverse effects than human GH.
5.
《Comparative biochemistry and physiology. B, Comparative biochemistry》1992,101(3):533-542
- 1.1. Fat body from feeding-phase, last instar gypsy moth females incorporates l-[35S]methionine in vitro into two vitellogenins with the same molecular masses (165 and 180 kDa) as the apo-vitellogenins found in teh hemolymph and the apo-vitellins in teh eggs.
- 2.2. Both apo-vitellogenins are observed in the medium of fat body cultures, but only the 180 kDa apo-vitellogenin is observed in extracts of cultured tissue.
- 3.3. Synthesis and accumulation of the apo-vitellogenins are suppressed in a dose-dependent manner by topical treatment with the juvenile hormone analog, methoprene, prior to day 4.
- 4.4. This suppression suggests that a declining juvenile hormone titre is involved in the initiation of vitellogenin synthesis.
6.
《Comparative biochemistry and physiology. A, Comparative physiology》1989,92(2):163-169
- 1.1. The development of Gallena mellonella is strongly affected by a low temperature of 18°C (the last instar persists for more than one year, instead of about 9 days at 30°C). At 18°C the last instar Galleria mellonella larvae respond to juvenilizing treatment—chilling stress or juvenile hormone analogue—with a very low percentage or no supernumerary moults, respectively.
- 2.3. Experiments in which larvae subjected to such treatments were transferred from 18°C to 30°C and vice versa showed that for the realization of the larval programme after chilling stress application the higher (30°C) temperature is needed.
- 3.4. In last instar larvae reared at 18°C there coexist very high juvenile hormone titre and high juvenile hormone esterase activity.
- 4.5. This phenomenon which is found in both, chilled and unchilled larvae, is discussed.
7.
《The International journal of biochemistry》1983,15(12):1489-1491
- 1.1. The changes in the lysine-rich histone subfraction hl0 have been quantitatively studied in rat liver during the regeneration period after partial hepatectomy.
- 2.2. A gradual decrease in this protein was found early after operation with a minimal value around the time of maximal mitotic activity.
- 3.3. The reduction in the hl0 content paralleled well the increasing number 0f cells in the cell cycle.
8.
《Molecular & cellular proteomics : MCP》2019,18(2):169-181
Highlights
- •Quantitative proteomics of mitotic chromosome scaffold isolated from chicken DT40 cells.
- •BAZ1B identified in the isolated mitotic chromosome scaffold localizes to mitotic chromosome axes.
- •BAZ1B knockout caused prophase delay because of altered chromosome condensation timing and impaired mitosis progression.
- •BAZ1B knockout did not affect prometaphase chromosome structure.
9.
《Comparative biochemistry and physiology. A, Comparative physiology》1984,77(3):421-424
- 1.1. Assays are described for the putative molt-inhibiting hormone (MIH) from the sinus glands of American lobsters (Homarus americanus).
- 2.2. Homogenates of dissected sinus glands are able to significantly delay induced molts in eyestalkablated juvenile lobsters.
- 3.3. In addition, these extracts are also able to significantly decrease circulating titers of ecdysteroids (as measured by radioimmunoassay) when injected into ablated lobsters.
10.
11.
《Comparative biochemistry and physiology. A, Comparative physiology》1984,77(3):339-344
- 1.1. The cardiovascular physiology of adult Carcinus maenas (L.) emerging into air has been investigated at three different air temperatures.
- 2.2. Transition from seawater to air or vice versa triggered transient increases in cardiac and locomotor activity.
- 3.3. However, crabs became inactive 5–10 min after emerging from seawater (15°C) into air at the same temperature (15°C) or at lower temperatures (12–13°C) and heart rate fell.
- 4.4. At higher air temperatures (18–20°C) heart rate rose but to a lesser extent than predicted from aquatic Q10 heart-rate values.
- 5.5. Crabs were again quiescent in aerial conditions.
- 6.6. Mean arterial oxygen tension (Pao2) was ~ 74 mmHg in submerged crabs but fell to ~ 38 mmHg in air while mean arterial carbon dioxide tension (Pao2) increased from 1 to 4 mmHg resulting in respiratory acidosis.
- 7.7. A model of gill function is proposed to explain the development of internal hypoxia in air.
- 8.8. The results are discussed in relation to the distribution of adult and juvenile C. maenas in situ.
12.
《Comparative biochemistry and physiology. A, Comparative physiology》1987,86(1):119-126
- 1.1. Spike frequency adaptation has been studied on neurons of Helix pomatia subesophageal ganglia and interpreted by means of a behavioural model describing the phenomenon in neurons either silent or autorhythmic at rest.
- 2.2. At low stimulating currents the initial discharge frequency F(0) is linearly related to the current strength G.
- 3.3. In the linearity range F(0)/G each neuron was characterized by means of four model parameters: the proportionality constant between F(0) and G, the decay constant of the frequency, the inhibitory current from a single nerve impulse and the decay time constant of the inhibitory current.
- 4.4. The four parameters varied in different cells with a range of 0.18–4.98 Hz/nA, 1.02–3.85 sec, 0.05–0.95 nA and 1.74–22.33 see, respectively.
- 5.5. Experimental results have been analyzed considering inhibitory current, electrogenie sodium pump and other proposed adaptation parameters.
13.
《Comparative biochemistry and physiology. A, Comparative physiology》1992,101(4):729-737
- 1.1. All age groups gained mass during the active season, but mass-gain of adult females was delayed during lactation.
- 2.2. The relationship of body mass to metabolic rate varied widely; when the relationship was significant, R2 varied from 10.3 to 72.6%. Body mass affects VO2 more during lactation than at any other period.
- 3.3. Mean VinO2 of adult males was higher in June than that of adult, non-lactating females.
- 4.4. VO2 of reproductive females was significantly higher during lactation than during gestation or postlactation because specific VO2 varied. Specific VO2 of non-reproductive females declined over the active season.
- 5.5. Specific VO2 of all age groups declined between the premolt and postmolt periods. The reduced maintenance costs can contribute 20–46% to daily growth.
- 6.6. Observed VO2 was lower than the value predicted from intraspecific or interspecific Bm:M regressions.
- 7.7. VO2 of wild-caught marmots was lower than that of marmots maintained in the laboratory, probably because of dietary differences.
- 8.8. Because basal metabolism is a stage on a food-deprivation curve, we suggest that basal metabolic rate is not an appropriate measure of the metabolic activity of free-ranging animals.
14.
《Comparative biochemistry and physiology. B, Comparative biochemistry》1978,59(3):379-384
- 1.1. The lactate dehydrogenase (LDH) from Palaemon serratus muscle has been studied throughout the development of the animal.
- 2.2. Enzymatic activities have been traced by polyacrylamide gel electrophoresis and kinetic studies.
- 3.3. The existence of two enzymes (L1 and L2) has been demonstrated.
- 4.4. During the larval development, both L1 and L2 remain at a low level.
- 5.5. After the larvae hatch L1 and L2 gradually rise although L1 is predominant.
- 6.6. Measurement of kinetic parameters shows that the general behaviour of the enzymes of the embryo resembles that of the adult enzymes.
- 7.7. However, one can observe during the development a constant increase in the affinity of the enzyme towards its substrate, lactate.
15.
《Comparative biochemistry and physiology. A, Comparative physiology》1980,65(2):227-230
- 1.1. Premetamorphic Bufo woodhousii fowleri tadpoles exhibit a high critical thermal maximum (CTM) of 42.5°C which decreases during metamorphosis to 37°C.
- 2.2. The CTM of progressively larger (older) postmetamorphic or juvenile toads gradually increases until the adult CTM of 41.1°C is attained.
- 3.3. This gradual increase in CTM from juvenile to adult toad suggests that the physiological systems underlying thermal tolerance change or mature following metamorphosis until the adult condition is reached.
- 4.4. Basking in juvenile toads elevates their metabolic rate and thus may facilitate the acquisition of the adult physiological state.
16.
《Comparative biochemistry and physiology. A, Comparative physiology》1981,68(3):417-421
- 1.1. Salmon calcitonin binding by isolated gill cells from rainbow trout, Salmo gairdneri has been investigated.
- 2.2. The calcitonin receptor interaction is time- and temperature-dependent.
- 3.3. 50% of inhibition of the 125I labeled calcitonin binding is observed in presence of 1.5 ng/ml unlabeled salmon calcitonin.
- 4.4. Two types of receptors are described: a high affinity-low capacity site and a low affinity-large capacity site.
- 5.5. These studies strongly support the role of calcitonin as a hormone regulating the gill function in physiological conditions.
17.
《The International journal of biochemistry》1986,18(7):589-594
- 1.1. The properties of ATPase activity were studied with the cells at the early stationary phase of Saccharomycopsis fibuligera.
- 2.2. Optimal pH for the activity was approximately 7.
- 3.3. The activity was stimulated by Mg2+.
- 4.4. The activity was inhibited by NaF, DCCD, oligomycin, NaN3, NaVO3, or PCMB but not inhibited by ouabain.
18.
《Comparative biochemistry and physiology. A, Comparative physiology》1981,68(3):429-436
- 1.1. Some aspects of the gas exchange system of a diving lizard, Physignathus lesuewii were studied.
- 2.2. Breathing patterns were analysed.
- 3.3. Breathing rate increases logarithmically with temperature and Q10 = 1.8. LogBR = −0.237 + 0.0256 T.
- 4.4. Gas tensions in lung air and arterial and venous blood were measured. Arterial pH declines with increasing temperature.
- 5.5. Temperature has a marked effect on oxygen affinity of the blood (ΔH = −10.1 kcal mol−). A Bohr effect was also noted.
- 6.6. CO2 equilibrium curves were drawn.
- 7.7. The results are considered with a view to anticipating the efficiency of the gas exchange system of this species under conditions of variable temperature and during diving.
19.
《Comparative biochemistry and physiology. B, Comparative biochemistry》1993,104(3):651-654
- 1.1. The biological properties of venoms from juvenile and adult common tiger snakes (Notechis scutatus) were compared.
- 2.2. The lethality, procoagulant activity and enzymatic activities of the juvenile venom were not substantially different from those of the adult venom.
- 3.3. Electrophoretic studies, however, indicated some minor differences in the protein composition of the juvenile and adult venoms.
20.
《Comparative biochemistry and physiology. A, Comparative physiology》1979,62(3):545-548
- 1.1. Adult male Atremia salina L. were acclimated to five different oxygen concentrations and their respiration in response to environmental oxygen concentrations was determined.
- 2.2. Anemia is a respiratory regulator over a wide range of partial O2 pressures. A critical oxygen tension exists and decreases with acclimation to lower pO2.
- 3.3. Hypoxic conditions induce the production of hemoglobin III.
- 4.4. Lactic acid is produced during anaerobiosis.
- 5.5. Production of Hb III and lactic acid, being inversely proportional to the acclimation level, has to be considered as a long term or short term adaptation to hypoxic conditions.