共查询到20条相似文献,搜索用时 31 毫秒
1.
J. Fuska Alžbeta Fusková J. Šmarda J. Mach 《Cellular and molecular life sciences : CMLS》1979,35(3):406-407
Summary Proliferation of murine leukemia cells P388 is stimulated by less than 1.0 mg/ml colicin E3, while being inhibited by higher concentrations. By 1.6 mg/ml colicin E3, uptake of thymidine into cold TCA-precipitable fraction is decreased by 59% during 24 h, uptake of uridine by 29%. 相似文献
2.
A single s.c. injection of 20-methylcholanthrene (1 mg in 0.2 ml olive oil) is found to stimulate the relative uptake of uridine-3H by the skin and the s.c. tissue 17- and 3fold respectively, 24 h post-administration. 相似文献
3.
Summary Colicin E3 increased the capacity of peritoneal exudate leucocytes to reduce iodo-nitro-tetrazolium-chloride to formazane. This effect was directly dependent on its concentration within the range 103–105 lethal units per cell. In control experiments, dectran C exerted no influence on the rate of this activity and colicin E3 did not convert INT to formazane. 相似文献
4.
Summary A single s.c. injection of 20-methylcholanthrene (1 mg in 0.2 ml olive oil) is found to stimulate the relative uptake of uridine-3H by the skin and the s.c. tissue 17- and 3fold respectively, 24 h post-administration. 相似文献
5.
The ammonia uptake in A. nidulans was found to be linear for about 20 min, and was proportional up to 1.5 mg/ml dry cell density. The transport of ammonia does not involve energy. Normal and biotin deficient A. nidulans showed an identical Km-values of 10.26 X 10(-5) M ammonia for uptake. The uptake of ammonium ion has been shown to be regulated by the intracellular concentration of ammonia. 相似文献
6.
B Halpern J Parlebas 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1977,285(16):1593-1597
Immune response to bovine serum albumin (BSA) at dose of 2,50 mg/kg which is rather a weak immunogen in Rabbits, when given intravenous was highly potentiated when the animals received a previous single intravenous infection of 2 mg/kg of C. parvum, followed by subsequent BSA anamnestic challenges for several months. Thus, the antibody amounts synthesized following the 1st anamnestic injection (3 weeks) were 0,260 mg/ml in the control versus, 0,800 mg/ml in the C. parvum pretreated groups; following the 2nd anamnestic challenge (12 weeks afterwards) 1 mg/ml in the control versus, 2,50 mg/ml in the treated groups following the 3rd anamnestic challenge (28 weeks afterwards) 1,3 mg/ml in the control versus 5 mg/ml in the C. parvum pretreated groups; following the 4th anamnestic challenge (52 weeks afterwards) 0,300 mg/ml in the control versus 0,800 mg/ml in the C. parvum treated groups. On the whole for the four first anamnestic challenges the differences at peak levels between the control and C. parvum treated groups were about to 4. Furthermore, the antibody molecules synthesized by the C. parvum treated animals were found to belong to IgG class. The results suggest that the immunological mechanisms mobilized are peculiar to C. parvum since they could not be reproduced either by BCG or by Freun'd adjuvant under similar conditions. 相似文献
7.
Summary The ammonia uptake inA. nidulans was found to be linear for about 20 min, and was proportional up to 1.5 mg/ml dry cell density. The transport of ammonia does not involve energy. Normal and biotin deficientA. nidulans showed an identical Km-values of 10.26×10–5 M ammonia for uptake. The uptake of ammonium ion has been shown to be regulated by the intracellular concentration of ammonia.Acknowledgment. The award of research fellowship by the Govt of India, Department of Atomic Energy, Bombay, to JDD is acknowledged. 相似文献
8.
Summary Decreasing the glucose concentration from 1.0 mg/ml to 0.25 mg/ml has no detrimental effects on postblastocyst embryo development when either dialyzed fetal calf serum (20%) or bovine serum albumin (4.0 mg/ml) is used to supplement Eagle's Basal Medium (BME). Development is reduced in both serum-and BSA-supplemented BME devoid of glucose in comparison to glucose controls. Serum-supplemented media support better overall development than BSA-supplemented media. 相似文献
9.
Culture of L-929 fibroblasts in the presence of phenytoin (2.5-5.0 micrograms/ml) increased DNA synthesis, as indicated by increased [3H]thymidine uptake, while a higher dose (20 micrograms/ml) inhibited DNA synthesis. In like manner, a low dose of phenytoin (5.0 micrograms/ml) was effective in increasing inositol 1,4,5-trisphosphate formation while a higher dose (10 micrograms/ml) tended to inhibit this activity. These data suggest that the formation of inositol phosphate second messengers may play a role in phenytoin-induced fibroblast proliferation and connective tissue growth. 相似文献
10.
D H Garnier C Cayrol 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1979,288(18):1407-1410
Estrogens have been examined in the plasma of diploid and triploid newts Pleurodeles waltlii. Estradiol-17 beta (E2) and estrone (E1) were determined by radioimmunoassay, before and after enzymatic hydrolysis of the conjugates. Total (t) and unconjugated (u) E2 levels were positively correlated (E2u = 0.478 35 E2t + 0.579 98; r = 0.883), but no correlation was detected between E1 levels. No statistical difference was found for the estrogen levels between the different experimental lots of diploid newts (E2t = 7.5 +/- 0.37 ng/ml, E2u = 4.3 +/- 0.20 ng/ml, E1t = 2.19 +/- 0.08 ng/ml, E1t = 0.41 +/- 0.02 ng/ml) but every estrogen level was lower in the triploid group (E2t = 1.8 +/- 0.60, E2u = 1.0 +/- 0.18, E1t = 1.4 +/- 0.13, E1u = 0.3 +/- 0.04 ng/ml). This difference is discussed in relation to lower fertility of the triploid females. 相似文献
11.
I. C. Ononogbu 《Cellular and molecular life sciences : CMLS》1979,35(11):1428-1429
Summary Serum cholesterol was determined in 104 healthy Nigerians (57 males and 47 females). The average cholesterol concentration was 187±72.8 mg/100 ml (mean±SD) with a range of 60–480 mg/100 ml. Cholesterol levels were higher in males than in females and increased with age. Distribution of cholesterol level was generally skew to the left.Acknowledgment. I am grateful to Mr S. O. Oguike an Mr O. Uzoechi for technical assistance. I also thank Dr. E. O. Anosike for his help in arranging for the subjects of study. 相似文献
12.
Summary Phosphate uptake inClaviceps sp. strain SD-58 was found to be linear for 20 min, proportional to cell density in mg/ml, energy dependent, and taking place against a concentration gradient with a Km value of 45.45×10–5 M. Osmotic shock treatment to the cell caused a reduction in phosphate uptake associated with the release of binding protein. Partial restoration of uptake was observed on incubation of osmotically shocked cells with shock fluid. The results are discussed with reference to the effect of phosphate on alkaloid synthesis inClaviceps sp. strain SD-58. 相似文献
13.
A. Pani P. Obino P. Guarracino P. La Colla 《Cellular and molecular life sciences : CMLS》1994,50(1):29-33
4,6-dimethyl-2-amino-3,4,5-trimethoxyphenyl-pyrimidine (B-31) is a pyrimidine derivative previously reported to arrest the mitotic cycle of mammalian cells in metaphase. In the present study it is shown that B-31 also acts as a specific inhibitor of the cellular uptake of nucleosides. The uptake of purinic and pyrimidinic nucleosides is inhibited by 80–90% at concentrations in the range 5–20 μg/ml, whereas those of nucleobases, leucine, choline and glucose are unaltered at the maximum nontoxic dose of B-31 (25 μg/ml). Various mammalian (human, monkey and murine) and avian cell are equally sensitive to the inhibition of nucleoside transport. The antimitotic effect of B-31, by contrast, is species-specific: human cells are the most sensitive whereas monkey and chicken fibroblasts appear resistant to this effect. Both effects can be reversed by removal of B-31 from the medium; inhibition of nucleoside transport can also be reversed by high doses of the nucleosides themselves. 相似文献
14.
A Caratzali I C Roman 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1971,272(4):663-664
The effect of diphenyl hydantoin, (DPH) a nonbarbituate anticonvulsant drug, on chromosomes and fertility was tested in cultured human lymphocytes, mouse fertility, and rat maternal marrow chromosomes and fetal development. Whole human blood from 5 male and 5 female subjects was cultured for 68 hours with phytohemagglutinin, then incubated for 2 hours in isotonic salts with .05-.3 mg per ml DPH, .02 mcg per ml colchicine, or .4 mg per ml sodium diethylbarbiturate. The mean number of metaphases per 1000 stimulated cells was 10.0 in controls, 40.3 with colchicine, 27.9 with diethylbarbiturate, and 30.5 with .25 mg DPH per ml. Both diphenylbarbiturate and DPH produced linear dose effect curves. These results were demonstrated not to be due to urea, since there were no differences in urea content, with a 2 hour urease micromethod. Mouse fertility was totally inhibited in 6 virgin mice given .1mg DPH daily for 10 days compared to 41 pups both of 6 control mice. In 6 pregnant rats given 25 mg DPH per 100 gm/orally 4 times daily for 2 days on gestation Days 7 and 8, there were 5 rats with all fetuses resorbed and 1 rat with 3 living and several resorptions. 6 controls had 6-14 normal fetuses each. 50 metaphase plates from each rat's femoral marrow and each fetus were examined 2 hous after injecting .3 mg colchicine per 100 gm. 30% of the metaphase cells from treated females and fetuses showed strongly contracted chromosomes and reduced number os "pulverized" chromosomes. These phenomena may have been due to inhibition by DPH of folic acid metabolism which is involved in purine synthesis. 相似文献
15.
Captopril (SQ 14,225): In vitro and in vivo influence on the proliferative response of rat lymphocytes 总被引:1,自引:0,他引:1
Lise Binderup E. Bramm E. Arrigoni-Martelli 《Cellular and molecular life sciences : CMLS》1982,38(3):399-401
Summary Captopril in vitro (50–500 g/ml) increased3H-TdR incorporation in unstimulated and mitogen-stimulated cultures of rat lymphocytes. Unseparated spleen and lymph node cells of rats orally treated with captopril (50 mg/kg/day×4) showed decreased basal and mitogen stimulated3H-TdR incorporation. The removal of macrophages abrogated this inhibitory effect. Leucine aminopeptidase activity of macrophages was reduced — in vivo and in vitro — by captopril.Acknowledgments. The authors thank the Squibb Institute for Medical Research for the gift of Captopril. The excellent technical assistance of Ms B. Hasselriis, Ms B. Rumler and Ms E. Greve Petersen is gratefully acknowledged. 相似文献
16.
M T Bluet-Pajot C Schaub 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1978,286(23):1707-1710
The authors investigated basal levels of plasma immunoreactive growth-hormone in the rat (R-GH) after administration of 3 different anesthetic drugs: urethan, chloral hydrate and gamma-hdroxy-butyrate (GHB). Lowest R-GH concentrations (5 +/- 3 ng/ml) are observed after urethan; they are significantly higher (15 +/- 4 ng/ml) after chloral hydrate but this anesthetic also causes hyperglycemia (210 +/- 30 mg/100 ml). Normal blood glucose levels are observed under GHB narco-analgesia which elicits a clear-cut R-GH secretory episode (70 +/- 5 ng/ml); basal values (12 +/- 3 ng/ml) are maintained for several hours thereafter. 相似文献
17.
Physostigmine in a dose of 0.1 mg/kg i.v. expressly stimulated the oxygen uptake in the rat cerebral cortex. This effect was blocked by propranolol and seems be mediated by catecholamines. Since atropine also antagonized the stimulant effect of physostigmine, it appears that the action of physostigmine is primarily cholinergic and that the adrenergic effect is a secondary phenomenon. The higher dose of physostigmine (0.4 mg/kg i.v.) caused a depression of rat brain oxygen uptake. 相似文献
18.
朱妮 《世界科技研究与发展》2011,33(5):882-884,941
目的 研究姜黄素对HepG2细胞凋亡的促进作用,并探讨其可能的的作用机制.方法 实验分为空白对照组、1 mg/ml、1.5mg/ml、2mg/ml的姜黄素处理组,MTT法检测不同浓度姜黄素对细胞增殖抑制情况;电镜观察细胞形态及其结构变化;流式细胞术检测凋亡率;Western blot检测各组作用24 h后细胞中bcl-... 相似文献
19.
P. Ehrhardt 《Cellular and molecular life sciences : CMLS》1965,21(8):472-473
Summary In the honeydew ofMegoura viciae
Buckt., sucking on the sieve tube sap ofVicia faba, the following cations are present in measurable quantities: potassium (13.0–14.1 mg/ml), sodium (0.04–0.051 mg/ml), magnesium (1.8–2.3 mg/ml) and calcium (0.07–0.09 mg/ml). There are only traces of copper, iron, manganese, zinc, cobalt and molybdenum. Amongst the anions, phosphate was found at 1.9–2.5 and chloride at 0.02–0.05 mg/ml, whereas nitrate and sulphate could not be detected. 相似文献
20.
Summary Inhaled concentrations of nitrous oxide (80%), halothane (0.5%), trichloroethylene (0.5%) and s.c. ethanol (1 ml/kg) caused similar degrees of excitation and ataxia in mice. Nitrous oxide, tricholoroethylene and ethanol caused analgesia (hot plate and writhing tests), but only that caused by nitrous oxide was antagonized by naloxone (20 mg/kg). Halothane lacked analgesic activity. 相似文献