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1.
L. Gao Y. Zhang W. Qiu W. Xu X. Feng J. Ren X. Jiang H. Wang D. Zhao Y. Wang 《Cell proliferation》2009,42(1):83-93
Objectives: To explore proliferation of glomerular mesangial cells (GMC) and secretion of extracelluar matrix (fibronectin induced by sublytic C5b-9 complexes), and then ascertain the role of phosphatidylinositol 3-kinase (PI3-k)/Akt signal pathway in these processes, by using small hairpin RNAs.
Material and methods: The expression of cyclin D2 , 3 H-thymidine into DNA and production of fibronectin including thrombospondin-1 and transforming growth factor-β1 in the GMCs stimulated by sublytic C5b-9 or transfected with expression vectors of PI3-k and Akt short hairpin RNA or LY294002 (PI3-k inhibitor) were measured by Real-time quantitative polymerase chain reaction (PCR), Western blot, enzyme-linked immunosorbent assay (ELISA) and 3 H-thymidine incorporation (3 H-TdR), respectively.
Results: The expression of cyclin D2 , 3 H-thymidine into DNA and fibronectin in the GMCs stimulated by sublytic C5b-9 could all be increased, and the elevations of these parameters mentioned above were also markedly reduced in the GMCs transfected with vectors of PI3-k and Akt short hairpin RNA or LY294002, respectively.
Conclusions: These data indicate that sublytic C5b-9 can promote proliferation of GMCs and secretion of fibronectin as well as synthesis of thrombospondin-1 and transforming growth factor-β1 . The PI3-k/Akt signal pathway in these reactions, mediated by sublytic C5b-9 complexes, may play at least a partial role. 相似文献
Material and methods: The expression of cyclin D
Results: The expression of cyclin D
Conclusions: These data indicate that sublytic C5b-9 can promote proliferation of GMCs and secretion of fibronectin as well as synthesis of thrombospondin-1 and transforming growth factor-β
2.
Cytokinin-induced switch in development in excised cotyledons of radiata pine cultured in vitro 总被引:2,自引:0,他引:2
Victor M. Villalobos Melvin J. Oliver Edward C. Yeung Trevor A. Thorpe 《Physiologia plantarum》1984,61(3):483-489
Cotyledons of Pinus radiata D. Don were cultured under shoot-forming (plus cytokinin) and elongating (minus cytokinin) conditions. Using. autoradiographic and precursor incorporation techniques, the sites and rate of macromolecular synthesis were examined during the first five days in culture. Active incorporation of 3 H-thymidine, 3 H-uridine and 3 H-leucine occurred. In shoot-forming cotyledons the incorporation became preferentially located in the epidermal and sub-epidermal cell layers in contact with the medium. In elongating cotyledons, in contrast, incorporation was randomly distributed, and the amount of incorporation declined with time. Biochemically, differences in DNA, RNA and total protein synthetic patterns were observed. In elongating cotyledons the rates of RNA and protein synthesis were higher during the first 48 h than in shoot-forming tissues, after which the synthetic rates were similar. Two peaks of newly formed DNA were observed in both tissues. These findings indicate that the cytokinin-induced changes in developmental pathways began within 24 h in culture. 相似文献
3.
ANTONIETTA NICOTRA MARIO ARIZZI PATRIZIA VALENTINA GALLO 《Development, growth & differentiation》1984,26(3):273-280
Protein synthetic activity has been studied during spermiogenesis of Paracentrotus lividus by high-resolution autoradiography using 3 H-leucine as a labeled precursor. Under the adopted experimental conditions 3 H-leucine is incorporated during the whole spermiogenesis period. The early spermatid is the most active stage and it shows labeling over the nucleus, the cytosol and the mitochondria. Nuclear 3 H-leucine incorporation progressively decreases as spermiogenesis proceeds. Cytosol labeling shows similar values at early and intermediate spermatid and it undergoes a considerable decreases at late spermatid. Mitochondrial grain density increases from early to intermediate spermatid and it remains almost constant at late spermatid.
Our results are compared with the data reported for other animal groups and possible functions of the observed protein synthesis are discussed. 相似文献
Our results are compared with the data reported for other animal groups and possible functions of the observed protein synthesis are discussed. 相似文献
4.
AKIRA NAGATANI HIDEHO SUZUKI MASAKI FURUYA 《Development, growth & differentiation》1983,25(2):217-226
Protein synthesis during photoinduced, synchronous progression of the cell cycle in single-celled protonemata of the fern Adiantum capillus-veneris was studied by tracer techniques. Nuclei of the protonemata were labelled with 3 H-thymidine during spore germination so that the amount of 3 H incorporated into the TCA-insoluble fraction of the cells could be used as a measure of the cell number in each sample. The rate of the incorporation of 14 C-amino acids into TCA-insoluble materials was not significantly varied at different stages of the cell cycle or by treatment with blue light. Extracts of cells labelled with 35 S-methionine at various times after the transfer from red light condition (G0 ) to darkness (G1 to S) were analyzed by two-dimensional gel electrophoresis. At least 3 of about 200 spots showed significant changes in intensity on fluorograms. Spot A (molecular weight 20,000, isoelectric point 6.3) was detectable only in early G1 , whereas spot B (molecular weight 19,500, isoelectric point 6.3) was found only in the late G1 and S phases. When the cells were exposed to blue light before the dark incubation, the times of disappearance of spot A and appearance of spot B were advanced depending upon the progression of the cell cycle but not upon the clock time. 相似文献
5.
Gldfish, Carassius auratus of varying sizes were conditioned in continuous light or darkness f or 10, 20 and 30 days and the incorporation of 3 H-thymidine into the gonads was investigated to attempt to develop a bioassay for fish gonadotropins.
The 24-hour gonadal3 H-thymidine of 10-day conditioned fish was significantly less at the dose level of 0.5 μCi 3 H-thymidine/fish compared to 1.0, 2.0 and 3.0 μCi/fish which gave gonadal activities not significantly different from each other. Thus, for all subsequent work the dose of 1.0 μCi/fish was used.
Photoperiod of continuous light or darkness had little effect on fish weighing less than 11 g but in fish 11-15 g conditioned for 20 days in darkness and fish greater than 16 g conditioned for 10 days in darkness, depression in gonadal3 H-thymidine incorporation occurred. In fish 11-15 g, prolonged conditioning for 30 days in darkness induced more gonadal activity than was observed at 20 days.
The effect of injection of Channa striatus pituitary extract at doses of 1 mg/10 g body weight and 5 mg/10 g body weight induced a significant increase in3 H-thymidine incorporation in the gonads over saline injected controls. The results suggest the potential of using photoperiod as a means of inducing regression of gonads of suitable fish in a bioassay of gonadotropins. 相似文献
The 24-hour gonadal
Photoperiod of continuous light or darkness had little effect on fish weighing less than 11 g but in fish 11-15 g conditioned for 20 days in darkness and fish greater than 16 g conditioned for 10 days in darkness, depression in gonadal
The effect of injection of Channa striatus pituitary extract at doses of 1 mg/10 g body weight and 5 mg/10 g body weight induced a significant increase in
6.
ANDREAS KISTLER 《Differentiation; research in biological diversity》1982,21(1-3):168-174
The addition of retinoic acid to fetal rat bones in culture induces the release of proteoglycans followed by cartilage resorption. In this system retinoic acid markedly suppressed 3 H-leucine and 3 H-mannose incorporation into acid-precipitable macromolecules, and specifically changed the 3 H-leucine incorporation pattern as revealed by gel electrophoresis. Tunicamycin, which selectively inhibits glycosylation of the asparagine residues in proteins, prevented the cartilage cell degradation in response to retinoic acid. Inhibitors of DNA synthesis did not affect the retinoic acid-induced changes indicating that cell division was not required for the cartilage degradation processes induced by retinoic acid. In consideration of our previous and present demonstrations that retinoic acid-induced cartilage resorption required RNA, protein, and glycoprotein synthesis and specifically changed the protein synthesis pattern, we suggest that retinoic acid may exert its action by altering gene expression. 相似文献
7.
Microbial activity associated with seston in headwater streams: effects of nitrogen, phosphorus and temperature 总被引:2,自引:0,他引:2
SUMMARY 1. The influences of temperature and dissolved nitrates and phosphates on microbial activity associated with suspended fine particulate organic matter (seston) were evaluated in four headwater streams in the southern Appalachian Mountains.
2. Temperature manipulations of ± 5°C always induced significant changes in [14 C] glucose mineralization (ANOVA; P <0.05) and [3 H]thymidine incorporation (ANOVA; P <0.05).
3. Nutrient amendments of 1.0 mg NO3 I−1 and 0.05 mg PO4 I−1 induced no significant alterations in bacterial mineralization of [14 C]glucose (ANOVA; P >0.05) or incorporation of [3 H]thymidine (ANOVA; P >0.05) in short-term (i.e. 3 h) experiments.
4. Microorganisms attached to refractory particulate organic matter do not appear to be limited by nitrogen or phosphorus even in streams with ambient nutrient concentrations as low as 0.06 mg NO3 I−1 and <0.03 mg PO4 I−1 .
5. Our results indicate that variations in water temperature resulting from diurnal and seasonal temperature fluctuations, forest clear-cutting, and catchment elevation and aspect can have marked effects upon microbial activity and production, while short-term alterations in nutrient regime appear to have no significant effect on microbial activity associated with seston. 相似文献
2. Temperature manipulations of ± 5°C always induced significant changes in [
3. Nutrient amendments of 1.0 mg NO
4. Microorganisms attached to refractory particulate organic matter do not appear to be limited by nitrogen or phosphorus even in streams with ambient nutrient concentrations as low as 0.06 mg NO
5. Our results indicate that variations in water temperature resulting from diurnal and seasonal temperature fluctuations, forest clear-cutting, and catchment elevation and aspect can have marked effects upon microbial activity and production, while short-term alterations in nutrient regime appear to have no significant effect on microbial activity associated with seston. 相似文献
8.
Activation of rainbow trout macrophages 总被引:1,自引:0,他引:1
Rainbow trout peritoneal macrophages were stimulated in vitro using Concanavalin A (Con A) and in vivo using formalin-killed Aeromonas salmonicida in Freund's incomplete adjuvant (FIA). Whether these cells had been activated was determined by the measurements of oxygen anions (NBT reduction), H2 O2 production (oxidation of phenol red), RNA synthesis (3 H-uridine incorporation), acid phosphatase activity and bactericidal activity.
In vitro -stimulated macrophages showed an increased NBT reduction and3 H-uridine incorporation over a range of Con A concentrations, compared with untreated control macrophages, but no detectable increases in H2 O2 production or bactericidal activity were observed. On the other hand, in vivo -stimulated peritoneal cells showed increases in all the assays compared with FIA-elicited control cells, and were considered to have been activated. 相似文献
In vitro -stimulated macrophages showed an increased NBT reduction and
9.
Abstract The biosynthesis of DNA, RNA, proteins and lipids in the presence of antiserum to sulfolipids was investigated by studying the incorporation of radiolabelled precursors like 3 H-thymidine 14 C-uracil, 14 C-leucine and 14 C-Acetate into their respective macromolecules. Antiserum to sulfolipids had a inhibitory effect on the biosynthesis of all these components. Antiserum also exhibited a growth inhibitory effects as compared to normal serum. 相似文献
10.
C. A. Arce Marta E. Hallak J. A. Rodriguez H. S. Barra R. Caputio 《Journal of neurochemistry》1978,31(1):205-210
Abstract— Incorporation of [14 C]tyrosine into the C-terminal position of α-tubulin of rat brain cytosol was 10-fold higher for non-assembled than for assembled tubulin. The incorporation into tubulin from disassembled microtubules was higher than into non-assembled tubulin; therefore, the low incorporation into microtubules was not due to a lower acceptor capacity of their tubulin constituent.
[14 C]Tyrosine was released from assembled and non-assembled [14 C]tyrosinated tubulin by the action of an endogenous carboxypeptidase. Release from non-assembled tubulin was shown by incubating a tubulinyl-[14 C]tyrosine preparation in the presence of CaCl2 at a concentration that abolished microtubule formation. Release from microtubules was inferred from the observation that the percentages of [14 C]tyrosine released and the decrease of the specific radioactivity of the recovered microtubules were practically identical and did not change after a 10-fold dilution of the incubated microtubules.
[3 H]Phenylalanine was released from a preparation of tubulinyl-[3 H]phenylalanine also by an enzymatic activity.
The capacity of a tubulin preparation to incorporate tyrosine was increased 43% by pre-treatment with endogenous carboxypeptidase.
Tubulin tyrosinated in vitro was assembled to the same extent as native tubulin. After a mixture of tubulinyl-[14 C]tyrosine and tubulinyl-[3 H]phenylalanine was partially assembled, the ratio of 14 C/3 H found in the microtubules was the same as in the non-assembled tubulin fraction. 相似文献
[
[
The capacity of a tubulin preparation to incorporate tyrosine was increased 43% by pre-treatment with endogenous carboxypeptidase.
Tubulin tyrosinated in vitro was assembled to the same extent as native tubulin. After a mixture of tubulinyl-[
11.
A. Lupulescu 《Prostaglandins & other lipid mediators》1975,10(6):573-579
The effect of exogenous prostaglandins E1, E2 and F2 (PGE1, PGE2 and PGF2) on 3H-leucine, 3H-uridine, 3H-thymidine and 3H-proline incorporation in experimental cutaneous wounds has been studied in rats.
Prostaglandins E1 and E2 markedly stimulate the incorporation of these tritiated precursors, into protein, RNA, DNA and collagen synthesis, whereas F2 inhibits it. All tested prostaglandins exhibit their maximum effect within the first hours following administration. Most active is PGE1. These observations indicate that application of prostaglandins significantly stimulate incorporation with protein, RNA, DNA and collagen synthesis in the skin of wounded rats and thus, may play a role in epidermal cell growth and division as well as in scar-forming tissue. 相似文献
12.
Josefina García-Cantizano Juan I. Calderón-Paz Carlos Pedrós-Alió 《FEMS microbiology ecology》1994,14(1):53-64
Abstract Heterotrophic bacterial activity was measured by means of the 3 H-thymidine (3 H-TdR) incorporation technique in Lake Cisó, a small holomictic lake with anoxic hypolimnion. We tested several methodological questions across the vertical profile: TdR concentration at which maximal incorporation is reached, linearity of incorporation and isotope dilution, during holomixis and stratification periods. The TdR concentration at which maximal incorporation is reached changed seasonally and vertically. During holomixis, maximal incorporation was not always reached at concentrations up to 40 nM. Uptake was always linear in short incubation times and decreased from epi- to hypolimnion. The isotope dilution technique indicated a degree of participation in DNA synthesis higher than 50%, although a linear relationship between the inverse of 3 H-TdR incorporation and increasing ‘cold’ thymidine concentration was not always observed. Autoradiographic experiments showed a low percentage of bacteria taking up 3 H-TdR in both aerobic and anaerobic samples. The percentage of total labeled bacteria seemed to be generally higher in the metalimnion (11% maximal value) than in the hypolimnion. Labeled Amoebobacter and Chromatium cells were detected in field samples. Amoebobacter cells photoassimilated TdR in culture. Therefore, our results show that 3 H-TdR incorporation is not an appropriate technique to estimate bacterial secondary production in anaerobic systems and in oxic-anoxic interfaces. 相似文献
13.
THE EFFECT OF DIABETES, INSULIN AND WALLERIAN DEGENERATION ON LEUCINE METABOLISM OF ISOLATED RAT SCIATIC NERVES 总被引:4,自引:3,他引:1
Maria G. Buse H. Franklin Herlong Dorothy A. Weigand S. S. Spicer 《Journal of neurochemistry》1976,27(6):1339-1345
Abstract– 14 CO2 production and 14 C incorporation into proteins was studied in isolated rat sciatic nerves during incubation with 0.1 mM-[1-14 C]leucine. Rats were made diabetic with streptozotocin. Nerves from diabetic rats incubated with glucose oxidized more [14 C]leucine than controls. This difference was abolished in the presence of insulin (1 mU/ml). The effects of diabetes and insulin on leucine oxidation could not be demonstrated in the absence of glucose. Insulin stimulated the incorporation of [14 C] from leucine into proteins by nerves from controls and diabetic rats.
Nerves undergoing Wallerian degeneration showed a marked increase in DNA content and stimulated incorporation of [14 C]leucine into proteins. 14 CO2 production from leucine proceeded at 75% of the rate observed in intact nerves. Neither insulin nor diabetes affected leucine metabolism in degenerating nerves.
Neither the extracellular space nor the concentration of free amino acids were significantly different in nerves obtained from control and diabetic rats, except for lower glutamine content in the latter.
In vitro leucine metabolism of nerves is affected by diabetes, insulin and the integrity of the axon. The Schwann cell is suggested as a possible site of the observed changes in leucine metabolism. 相似文献
Nerves undergoing Wallerian degeneration showed a marked increase in DNA content and stimulated incorporation of [
Neither the extracellular space nor the concentration of free amino acids were significantly different in nerves obtained from control and diabetic rats, except for lower glutamine content in the latter.
In vitro leucine metabolism of nerves is affected by diabetes, insulin and the integrity of the axon. The Schwann cell is suggested as a possible site of the observed changes in leucine metabolism. 相似文献
14.
F. Galdiero C. Romano Carratelli I. Nuzzo C. Bentivoglio L. De Martino A. Folgore M. Galdiero 《FEMS immunology and medical microbiology》1995,10(3-4):235-244
Abstract The capacity of liposomes constituted by dycetyl-phosphate (0.009 mM), cholesterol (0.017 nM), lecithin (0.003 mM), and myristic (0.1 mM), stearic (0.1 mM), or oleic acid (0.1 mM) to modify the lymphocyte response to Brucella melitensis antigens in mice was studied. Mice treated with antigens mixed with liposomes containing myristic, stearic or oleic acid had higher antibody titres than mice given antigen suspended in a saline solution. Liposomes alone, without Brucella antigens, resulted in increased 3 H-thymidine incorporation by lymphocytes both in vivo and in vitro. The addition of polyclonal activators (LPS and ConA) caused a further increase of 3 H-thymidine uptake. Moreover, spleen lymphocytes from mice inoculated with Brucella antigens mixed with the liposomes had a significantly lower population of B lymphocytes (10%), and a notable increase in the Tc lymphocytes (20%). Autoradiography of sections of popliteal ganglia of treated mice showed that the radioactivity was concentrated mainly in the membrane structures of the cell. 相似文献
15.
Abstract— The incorporation in vivo of 32 P1 was significantly increased in all glycerophosphatide of preparations of denervated muscle membrane in frogs. There was no increase in incorporation of 32 P1 into sphingomyelin. Disuse induced by tenotomy did not significantly increase incorporation of 32 P1 into phospholipids of the muscle membrane. The phospholipid content of muscle membranes remained unchanged as a result of denervation or tenotomy. Denervation produced an increase in the incorporation of [2-3 H]glycerol into all glycerophosphatides in parallel with the increase in 32 P1 incorporation. Although the stimulated incorporation of 32 P1 was increased in the regions of the muscle membrane rich in endplates, the most marked effect was in the endplate-poor region where activity in phosphatidylserine was most markedly increased. 相似文献
16.
Abstract. The kinetics of isthmal cells in mouse antrum were examined in three ways: (a) the duration of cell cycle and DNA-synthesizing (S) stage was measured by the 'fraction of labelled mitoses' method; (b) the duration of interphase and mitotic phases was determined from how frequently they occurred; and (c) mice were killed at various intervals after an intravenous injection of 3 H-thymidine to time the acquisition of label by the various phases of mitosis.
The duration of the isthmal cell cycle was found to be 13.8 hr and that of the DNA-synthesizing (S) stage, 5.8 h. Estimates for the duration of the G1 and G2 stages were 6.8 and 1.0 hr, respectively.
From the frequency of mitotic phases, defined as indicated in the preceding article (El-Alfy & Leblond, 1987) and corrected for the probability of their occurence, it was estimated that prophase lasted 4.8 hr; metaphase, 0.2 hr; anaphase, 0.06 hr and telophase, 3.3 hr, while the interphase lasted 5.4 hr. In accordance with this, the duration of the whole mitotic process was 8.4 hr.
Ten minutes after an intravenous injection of3 H-thymidine, 38% of labelled isthmal cells were in interphase and 62% in early or mid prophase, while cells in late prophase and other mitotic phases were unlabelled. After 60 min, label was in late prophase, after 120 min, in mid telophase and after 180 min, in late telophase.
We conclude that there is overlap between some mitotic phases and cycle stages. Thus, while nuclei are at interphase during the early third of S, they are in prophase during the late two-thirds as well as during G2 . Also, nuclei are in telophase during the early half of G1 but at interphase during the late half. Differences in nuclear diameter show that subdivision of both S and G1 into early and late periods is practical. 相似文献
The duration of the isthmal cell cycle was found to be 13.8 hr and that of the DNA-synthesizing (S) stage, 5.8 h. Estimates for the duration of the G
From the frequency of mitotic phases, defined as indicated in the preceding article (El-Alfy & Leblond, 1987) and corrected for the probability of their occurence, it was estimated that prophase lasted 4.8 hr; metaphase, 0.2 hr; anaphase, 0.06 hr and telophase, 3.3 hr, while the interphase lasted 5.4 hr. In accordance with this, the duration of the whole mitotic process was 8.4 hr.
Ten minutes after an intravenous injection of
We conclude that there is overlap between some mitotic phases and cycle stages. Thus, while nuclei are at interphase during the early third of S, they are in prophase during the late two-thirds as well as during G
17.
The (C2 H4 + H2(C2 H2 ) )/15 N2 ratios of 15 clover- Rhizobium symbionts. soybean, and black medick symbionts were measured. Relative efficiency based on the C2H4 production and on 15 N2 incorporation were compared, and in most symbionts there was little difference between the two measures of relative efficiency. Total measurable electron flux through nitrogenase during acetylene reduction and 15 N2 incorporation were nearly equal for most symbionts studied. The relative efficiency and the (C2 H4 + H2(C2 H2 ) )/15 N2 ratio showed an inverse correlation. Use of this ratio appears preferable to use of the ratio of C2H2 reduction/N2 reduction. Some evolution of H2 was observed in the presence of C2 H2 . 相似文献
18.
Manuela Hartmann Mikhail V. Zubkov Adrian P. Martin David J. Scanlan & Peter H. Burkill 《FEMS microbiology letters》2009,298(2):166-173
Biologically available concentrations of individual dissolved amino acids in the open ocean are generally <1 nM. Despite this, the microbial turnover of amino acids is usually measured in hours indicating high demand. It is thought that the majority of uptake is due to bacterioplankton, although protists, particularly phototrophic protists, are also expected to take up amino acids. In order to assess the ability of protists to compete with prokaryotes for amino acids at subnanomolar concentrations, we examined the direct uptake of 3 H-leucine by phototrophic nanoflagellates (prasinophytes, pelagophytes and trebouxiophytes) and by associated bacteria using flow cytometric cell sorting. In contrast to 3 H-leucine-assimilating bacterial copopulations, none of the six studied nanoflagellates showed measurable direct uptake of 3 H-leucine, suggesting that the studied phototrophic protists were unable to utilize dissolved 3 H-leucine at natural oceanic concentrations. More practically, the flow-sorting technique allowed rapid and unequivocal differentiation of organic nitrogen uptake between prokaryotic cells and eukaryotic cells in mixed microbial populations, reducing the need to establish and maintain axenic algal cultures. 相似文献
19.
The granulocytic chalone is secreted by mature granulocytes and inhibits 3 H-thymidine incorporation of proliferating granulocytes in vitro . The effect and the cell line specificity of this chalone was assessed with the in vivo diffusion chamber culture technique. Tests were carried out on cultures from normal mouse bone marrow cells and mouse and rat blood leucocytes. The majority of the DNA synthesizing cells in marrow cultures were proliferating granulocytes. Macrophages and immunoblasts proliferated in rat leucocyte cultures, when the chambers had been carried for 5 days in host mice. Repeated chalone or control injections were given i.p. to the host mice during 6–7 hr prior to 3 H-thymidine injection. Isotope uptake of proliferative granulocytes was reduced by the chalone treatment. No such effect was found on the rat immunoblasts and macrophages. The viability of cultured cells was apparently not affected by the chalone treatment. 相似文献
20.
SYNOPSIS. The biologic characteristics of 4 strains of hartmannellid amoebae were compared. All contained cytoplasmic DNA, degraded thymidine to CO2 and killed chick embryos at 32 C. All except H. glebae secreted a lipogenic toxin and contained antigen(s) capable of sensitizing erythrocytes. A. castellanii , unlike the other 3, also killed chick embryos at 37 C. The Fernald strain of H. rhysodes differed from the other 3 in its higher cytoplasmic grain count of cells labelled with 3 H-thymidine and in its ability to induce the appearance of amoebic antigen within human cells. Increased nuclear labelling in the Fernald strain was observed with increasing concentrations of 3 H-thymidine. 相似文献