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1.
  • 1.1. In order to obtain a seasonal profile of LH, three adult male pudu (Pudu puda, Molina) were sampled monthly from the saphenous vein for a period of one year.
  • 2.2. A significant circannual variation of plasma LH levels was detected with an average peak value (1.77 ng/ml) recorded in February and nadir concentrations (0.19 ng/ml) observed in November.
  • 3.3. The peak level of testosterone (1.54 ng/ml) was detected in March, the time of the rut.
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2.
  • 1.1. A specific and sensitive sandwich enzyme-linked immunosorbent assay (ELISA) was developed for the measurement of low levels of serum immunoglobulin M (IgM) of chum salmon Oncorhynchus keta.
  • 2.2. In this assay, 5 μl serum was enough to measure the concentration of IgM and the minimum detectable concentration of serum IgM was about 5 ng/ml.
  • 3.3. Coefficients of variation within and between assays ranged from 2.90 to 9.61%.
  • 4.4. IgM concentrations remained at low level (< 300 ng/ml) until 40 days after hatching and then increased rapidly at the period of emergence (48 days after hatching).
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3.
  • 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.
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4.
  • 1.1. A method is described for the accurate and rapid measurement of protein- and non-protein-bound cortisol by miniature gel filtration in small volumes of plasma, e.g. of rodents.
  • 2.2. Binding of cortisol by guinea pig plasma proteins is strongly reduced at elevated temperature (4°C: 102 ± 12ng/ml; 40°C: 5 ± 2 ng/ml).
  • 3.3. Incubation of guinea pig plasma with 1–5000 ng cortisol resulted in a dose-dependent increase in cortisol bound to proteins (specific binding by corticosteroid binding globulin: 230 ± 12 ng/ml).
  • 4.4. Administration of 20 IU (1–24)ACTH induced a significant increase of total protein-bound and non-protein-bound cortisol.
  • 5.5. Values reported in this study agree well with those of previous investigations, in which bound and non-bound glucocorticosteroids were separated by gel filtration on large Sephadex® columns.
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5.
  • 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.
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6.
  • 1.1. myo-Inositol concentrations in oviduct, ovary and uterus were many-fold those of blood serum during all four stages of the estrous cycle of the female rat.
  • 2.2. Inositol concentration was higher in oviduct than in ovary or uterus and was lower in uterine fluid than in uterus.
  • 3.3. Estrus uteri had higher inositol concentrations than uteri in other phases of the cycle.
  • 4.4. In order to measure dynamic aspects of the distribution of inositol. the distribution of radioactivity among organs of the reproductive tract of mature female rats was measured 45 min after i.p, injection of [2-3H]myo-inositol.
  • 5.5. These organs concentrated inositol from the blood, and the tissue radioactivity (expressed as dpm/mg wet wt of tissue) increased in the sequence: vagina < cervix < uterus < ovary < oviduct.
  • 6.6. The uterus and ovary concentrated myo-inositol more strongly during proestrus than during metestrus. diestrus or estrus.
  • 7.7. The contents of proestrus follicles were more highly radioactive than was the ovary itself, whereas proestrus uterine fluid was less radioactive than the uterine tissue.
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7.
  • 1.1. Tubulin has been isolated from brain of carp (Cyprinus carpio), acclimated to summer temperatures (16–20°C), and its in vitro reassembly behavior has been characterized.
  • 2.2. Among the striking properties of this tubulin preparation is the temperature profile showing a high level of polymerization at the environmental temperature of carp.
  • 3.3. The critical tubulin concentration for assembly was 0.8 mg/ml, which was higher than mammalian tubulin purified by the cycle procedure.
  • 4.4. The microtubular protein showed three high mol.wt component and a minor component of about 43,000 daltons was also found to copurify with tubulin.
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8.
Normal human endometrium (classified by histology and date after last menstrual period) was cultured for 72h, and the output of prostaglandin F2α and 6-oxo-prostaglandin Fla detected by radioimmunoassay. Hormones/stimuli were added to the culture during the second day of culture for 5h and 19h periods.
  • 1.1) The output of prostaglandin F2α from cultured endometrium was significantly higher (p<0.05) at the beginning (d4–8) and end (d25–30) of the menstrual cycle, compared to mid-cycle (d13–24) endometrium. Significantly more prostaglandin F2α was released from proliferative than from secretory phase endometrium (p<0.02).
  • 2.2) Prostaglandin F2α release was rapidly stimulated by sodium arachidonate (20–300 μg/ml), and by calcium ionophore A23187 (5 μg/ml) at an extracellular calcium ion concentration of 1.8mM.The ionophore stimulation was greater in mid-cycle endometrium than in endometrium from the beginning or the end of the menstrual cycle.
  • 3.3) Estradiol-17β (10 ng/ml) gradually increased the output of prostaglandin F2α from secretory phase endometrium, and this stimulation was observed in the post-incubation period after hormone had been removed from the incubation medium.
  • 4.4) Oxytocin (1 × 10−5U/ml caused a more rapid stimulation of prostaglandin F2α output from secretory phase tissue (p<0.05 during the first 5h incubation period with hormone).
  • 5.5) Oxytocin (1 × 10−5 U/ml) and estradiol (long/ml) together significantly stimulated prostaglandin F2a production by proliferative as well as secretory phase endometria.
  • 6.6) A high dose of hydrocortisone (loo μg/ml) inhibited the output of prostaglandin F2α from proliferative and secretory phase endometrium and also from ionophore-stimulated endometrium. However, this dose of hydrocortisone did not inhibit the synthesis of prostaglandin F2a from exogenous arachidonic acid, or the estradiol-induced increase in prostaglandin F2α production.
  • 7.7) Co-culture of endometrium with myometrium did not modify the output of prostaglandin F2α or of 6-oxo-prostaglandin Fla from cultured tissues.
  • 8.8) These experiments suggest that arachidonic acid supply to the cyclooxygenase enzyme may vary during the menstrual cycle: and indicate a gradual increase in prostaglandin synthesising capacity in response to estrogen, more rapid control via oxytocin, and an interaction between estrogen and oxytocin to modulate prostaglandin F2a synthesis in human endometrium.
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9.
  • 1.1. The growth characteristics of Burkitt's lymphoma cells in suspension culture have been studied, and a mean population doubling time of 20–21 hr established for this cell line under a range of nutritional and physical conditions; data which have provided a basis for the assessment of the reproducibility of the culture techniques and conditions which were employed in the subsequent studies.
  • 2.2. Activities of lactate dehydrogenase (LDH), aldolase and esterase, as well as the cellular content of total soluble protein, and the isoenzyme pattern of LDH, were monitored in randomly growing Raji cells for the duration of a complete growth cycle.
  • 3.3. In this period, the temporal pattern of variation in the levels of total soluble protein were seen to reflect alterations in LDH activity during a single growth cycle.
  • 4.4. The fluctuations observed in LDH activity were greater than those observed for either aldolase or esterase activity, and, from the data considered, the maximum degree of variation appeared to be confined to the initial stages of growth.
  • 5.5. Extracellular levels of LDH activity remained relatively constant throughout the growth cycle. so that the large fluctuations in intracellular LDH activity could not be attributed to either secretion or leakage of the enzyme into the culture medium.
  • 6.6. No gross changes in the pattern of LDH isoenzymes in these Raji cells were detected during the course of a single growth cycle.
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10.
  • 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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11.
  • 1.1. Five adult, female alligators (Alligator mississippiensis) were captured at night during the breeding season, and a blood sample taken within 5 min of capture.
  • 2.2. The alligators were physically restrained (tied to boards) and additional blood samples taken at 4, 8, 12, 16, 22, 28, 38, and 48 hr after capture. After the last blood sample was collected the animals were released.
  • 3.3. Plasma estradiol-17β and corticosterone were measured by radioimmunoassay. Estradiol declined significantly from initial values by 22 hr post capture, but remained unchanged for 48 hr.
  • 4.4. Plasma corticosterone rose from a mean of 0.8 ng/ml at capture to 12.6 ng/ml after 4 hr. Corticosterone continued to rise up to 16 hr then declined after 22 hr. From 28 until 48 hr corticosterone again increased significantly.
  • 5.5. These results demonstrate that acute stress in female alligators causes significant suppression of plasma estradiol and a biphasic pattern of corticosterone secretion.
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12.
  • 1.1. Various systems for the maintenance of rat adipose tissue in tissue culture have been compared.
  • 2.2. Optimal conditions for tissue culture were medium 199 supplemented with insulin (10 μg/ml). streptomycin (10μ/ml). penicillin (6 μg/ml) and buffered with 25 mM Hepes. pH 7.3. with a gas phase of air and a temperature of 33 C; adipose tissue was either placed on grids at the air-liquid interface or was allowed to float on the liquid, depending on the age of the rat from which it came.
  • 3.3. The rates of glucose metabolism to CO2, fatty acids and glyceride glycerol. and also palmitate esterification in adipose tissue slices changed (but not in synchrony) over 3 days in tissue culture.
  • 4.4. It is concluded that the system should be of value for studying effects of hormones and other substances on adipose tissue metabolism over a period of several days.
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13.
  • 1.1. Renal function in migrating adult Atlantic salmon was studied in sea-water (SW) and following abrupt transfer to fresh water (FW).
  • 2.2. Urine flow rate of SW-adapted fish, 0.72 ml/kg/hr, increased 6.3-fold to 4.55 ml/kg/hr after 2–3 days in FW, later decreasing to around 1 ml/kg/hr.
  • 3.3. Changes in glomerular filtration rate and ion filtration rates largely paralleled changes in urine flow. In SW-adapted salmon about 4% of excreted magnesium is filtered. Tubular magnesium secretion declined within 1 day of FW transfer.
  • 4.4. During the period of maximum diuresis, urinary sodium loss is 77% of the branchial sodium uptake rate. This falls to less than 20% in FW-adapted fish.
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14.
  • 1.1. The glyoxylic acid cycle pathway could be regulated through the modulation of the isocitrate dehydrogenase-NADP activity. This enzyme is inhibited by NADPH.
  • 2.2. The effect on the glyoxylate cycle flux of variations in the rate of the NADPH-consuming pathways has been studied.
  • 3.3. Increase in the rate of NADPH-consuming activity by addition of H2O2 produces inhibition of the glyoxylate cycle and decrease in the NADPH/NADP ratio.
  • 4.4. These results suggest that the glyoxylate flux in Tetrahymena could be modulated by regulation of NADP-dependent isocitrate dehydrogenase by the NADPH/NADP ratio.
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15.
  • 1.1. Over an 8-year period, 19 biochemical parameters have been determined at various ages in the blood serum of 92 clinically healthy Lechwe waterbucks (Kobus leche), 33 males and 59 females.
  • 2.2. Significant differences have been noted with age. In neonates, the lowest values of total proteins, glucose, creatinine, urea, AST, ALT and iron have been noted; the highest ones have been seen for cholesterol, alkaline phosphatase, calcium and phosphorus.
  • 3.3. With regard to sex, raised values of glucose, urea, alkaline phosphatase and ALT, and lowered values of cholesterol, have been noted in juvenile females compared with males of the same age.
  • 4.4. In adult females, higher levels of urea and cholesterol and lower levels of glucose, triglycerides and natrium have been recorded compared with males.
  • 5.5. With sex and age, no significant changes have been found in the levels of GGT, magnesium, chlorides and copper.
  • 6.6. Out findings are discussed with those abstracted from the literature for related species.
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16.
  • 1.1. Blood glucose and lactate, serum total lipid and triglyceride, thyroxine (T4), epinephrine and norepinephrine concentrations and serum dopamine-β-hydroxylase activity were studied in 76 reindeer hinds and 127 calves with reference to the seasons.
  • 2.2. Blood glucose level tended to be lowest in Autumn, and blood lactate highest in Summer.
  • 3.3. Serum total lipids were smallest in Spring (2.8 g/l) and greatest in Autumn (5.3 g/l). Triglycerides were smallest in Winter (0.18 mmol/l) and highest in Autumn (0.32 mmol/l). In calves the total lipids increased during the neonatal period.
  • 4.4. Serum epinephrine correlated with the weight, age, blood glucose and total lipids of the animals. In adult animals the lowest serum epinephrine level was found in Spring and the highest in Autumn (55 vs 190 ng/ml).
  • 5.5. Serum norepinephrine concentration and dopamine-β-hydroxylase activity were highest in Spring and decreased towards Autumn. Parturition affected these parameters significantly.
  • 6.6. The preponderance of high levels of some blood constituents in Autumn may be attributable to the replenishment of energy supplies for Winter time and also to the rutting season.
  • 7.7. T4 was smallest in Spring and highest in Summer. It was slightly greater in Winter than in Autumn. This suggests that the metabolic rate is tower in Winter than in Summer. Thus, the adaptation of the reindeer to a cold climate mainly utilizes insulation.
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17.
  • 1.1. Three calcium-binding proteins have been purified from Ehrlich ascites tumor cells.
  • 2.2. They were identified by amino acid sequence analysis on selected fragments obtained by tryptic digestion.
  • 3.3. The proteins belong to the annexin family and were identified as annexins II, III and V.
  • 4.4. Antibodies raised against the proteins were used to examine for their presence in a number of murine tissues.
  • 5.5. The occurrence was found to be in reasonable accordance with earlier reports.
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18.
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19.
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20.
  • 1.1. Progesterone levels in Mytilus edulis males and females during the annual reproductive cycle were analysed in the whole animal and in the gonads using gas-liquid chromatography and radioimmunoassays.
  • 2.2. The high hormone levels in the whole animal were observed in July and October, coincident with the main spawning seasons.
  • 3.3. The levels of progesterone in gonad extracts also show a maximum in summer (July).
  • 4.4. The patterns of the progesterone levels in males and females throughout the annual reproductive cycle are similar.
  • 5.5. These data are discussed in relation to the role of progesterone in the regulation of sex-specific processes, particularly gametogenesis.
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