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1.
The mutagemc effects of microwave and chromium trioxide （CrO3） on Vicia faba root tip were studied. Micronucleus assay and chromosomal aberration assay were used to determine the mitotic index, the micronucleus frequency and chromosomal aberration frequency of Vicia faba root tip cells induced by microwave and CrO3. The results showed that the micronucleus frequency decreased, and that the mitotic index and chromosomal aberration frequency showed linear dose responses to CrO3, in treatment of microwave for 5 s. In microwave of 25 s, the mitotic index decreased, the micronucleus frequency and chromosomal aberration frequency increased with increase of CrO3 concentration. We concluded that microwave and CrO3 had antagonistic effect on the mitotic index of Vicia faba root tip cells, but had synergetic effect on micronucleus frequency and chromosomal aberration frequency of Viciafaba root tip cells. 相似文献
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Akinboro A Mohamed KB Asmawi MZ Sulaiman SF Sofiman OA 《Journal of Zhejiang University. Science. B》2011,12(11):915-922
In this study, freeze-dried water extract from the leaves of Myristica fragrans (Houtt.) was tested for mutagenic and antimutagenic potentials using the Allium cepa assay. Freeze-dried water extract alone and its combination with cyclophosphamide (CP) (50 mg/kg) were separately dissolved
in tap water at 500, 1000, 2000, and 4000 mg/kg. Onions (A. cepa) were suspended in the solutions and controls for 48 h in the dark. Root tips were prepared for microscopic evaluation. 2,2-Diphenyl-1-picrylhydrazyl
(DPPH) free radicals’ scavenging power of the extract was tested using butylated hydroxyanisole (BHA) and butylated hydroxytoluene
(BHT) as standards. Water extract of Myristica fragrans scavenged free radicals better than BHA, but worse than BHT. The extract alone, as well as in combination with CP suppressed
cell division, and induced chromosomal aberrations that were insignificantly different from the negative control (P≤0.05). However, cytotoxic and mutagenic actions of CP were considerably suppressed. The observed effects on cell division
and chromosomes of A. cepa may be principally connected to the antioxidant properties of the extract. The obtained results suggest mitodepressive and
antimutagenic potentials of water extract of the leaves of M. fragrans as desirable properties of a promising anticancer agent. 相似文献
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为研究硒镉联合作用对番茄根尖细胞遗传学效应,用不同硒浓度和100μmol/L镉联合处理番茄根尖24 h、48 h、72 h、96 h,统计有丝分裂指数、染色体畸变率和微核率.结果表明：单一镉处理时番茄根尖细胞有丝分裂指数下降,染色体畸变率和微核率增加,且随时间的延长而毒害加深.硒镉处理时,硒浓度低于1.0μmol/L时番茄根尖细胞有丝分裂指数增加,染色体畸变率和微核率下降,高于1.0μmol/L时番茄根尖细胞有丝分裂下降,染色体畸变率和微核率升高,但浓度过高时,微核率随着镉处理时间的延长反而有所降低,表现出低浓度硒对镉的毒害有缓解作用,高浓度硒与镉协同毒害作用. 相似文献
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In this study on the mutagenic effects of different concentrations of chromium trioxide (CrO3) on Vicia faba root tip, micronucleus assay and chromosome aberration assay were used to determine the mitotic indexes, micronucleus rate
and chromosome aberration rate of Vicia faba root tip cells. The results showed that the effects of CrO3 concentration on the mitotic indexes were complicated. CrO3 increases the micronucleus rate of Vicia faba root tip cells. It was found that within certain range of CrO3 concentration the micronucleus rate increased systematically with increased concentration of CrO3, but that the micronucleus rate decreased at higher level of CrO3 and that CrO3 also caused various types of chromosome aberration at a rate which increased systematically with increased concentration
of CrO3. We concluded that CrO3 has significant mutagenic effect on Vicia faba root tip cells.
Project supported by Wenzhou Technology Bureau (No. S2002A015) and Wenzhou “551” Talented People Fund of China 相似文献
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垃圾渗出液对蚕豆根尖细胞的诱变效应 总被引：2，自引：0，他引：2
以不同浓度的垃圾渗出液为诱变剂,测定蚕豆根尖细胞的有丝分裂指数、微核率和染色体畸变率。结果表明:垃圾渗出液能够降低蚕豆根尖细胞有丝分裂指数,能诱发较高频率的微核和染色体畸变,产生染色体断片、滞后染色体和染色体桥。随着垃圾渗出液处理浓度的增加,有丝分裂指数降低,而微核率和染色体畸变率均升高;随着垃圾渗出液浓度的进一步增加,染色体畸变率却下降,但仍明显高于对照组。 相似文献
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以蚕豆根尖为材料,研究厕洁灵、丝毛剂和蔬果清洗剂对蚕豆根尖细胞的遗传毒性.利用不同浓度的厕洁灵、丝毛剂和蔬果清洗剂为诱变剂,测定蚕豆根尖细胞的微核率和染色体畸变率.结果：不同浓度的洗涤剂能诱发较高频率的微核,还能诱导染色体产生多种类型的染色体畸变.结论：三种洗涤剂对植物根尖细胞具有明显的致突变效应,有一定的遗传毒性;其中洁厕剂的毒性最大,丝毛剂次之,果蔬洗涤剂最弱. 相似文献
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钱晓薇 《浙江大学学报(A卷英文版)》2004,5(12)
In this study on the mutagenic effects of different concentrations of chromium trioxide (CrO3) on Vicia faba root tip, micronucleus assay and chromosome aberration assay were used to determine the mitotic indexes, micronucleus rate and chromosome aberration rate of Viciafaba root tip cells. The results showed that the effects of CrO3 concentration on the mitotic indexes were complicated. CrO3 increases the micronucleus rate of Vicia faba root tip cells. It was found that within certain range of CrO3 concentration the micronucleus rate increased systematically with increased concentration of CrO3, but that the micronucleus rate decreased at higher level of CrO3 and that CrO3 also caused various types of chromosome aberration at a rate which increased systematically with increased concentration of CrO3. We concluded that CrO3 has significant mutagenic effect on Viciafaba root tip cells. 相似文献
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以大蒜根尖为材料,研究了紫外线对大蒜根尖的致畸效应.结果表明,紫外线可使染色体发生结构变异.在分裂间期出现微核、多核,在分裂期出现染色体桥、断片、粘连等畸变类型.紫外线照射25 min时能观察各种畸变类型,且畸变率较高. 相似文献
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用秋水仙素、8-羟基喹啉、对二氯苯、低温(<4℃)处理蚕豆根尖,比较分析了它们诱发蚕豆根尖细胞间期核和染色体畸变的效应. 相似文献
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以蚕豆根尖为材料,研究洗手液对蚕豆根尖细胞的致畸效应,采用蚕豆根尖细胞的微核试验方法和染色体畸变试验方法,以不同浓度的洗手液为诱变剂,测定蚕豆根尖细胞的微核率、有丝分裂指数和染色体畸变率．结果表明：不同浓度的洗手液能诱发较高频率的微核,还能诱导染色体产生多种类型的染色体畸变．结论是洗手液具有一定的遗传毒性． 相似文献
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Objective: To study the effects of different concentrations of antisense oligodeoxynucleotides (ASODN) on human pancreatic
cancer cell line PaTu8988s. Method: Human pancreatic cancer cell line PaTu8988s in exponential growth stage was used to study
the effect of different drug concentrations on the cell line in the presence of different concentrations (0 μg/ml, 5 μg/ml,
25 μg/ml, 50 μg/ml, 10 μg/m, 200 μg/ml) of ASODN and sense oligodeoxynucleotides (SODN). Cell counts and 3-[4,5-dimethylthiazolzyl]-2,5-diphenyl
tetrazolium bromide (MTT) assays were carried out. Results: The inhibitory rate on the cell line PaTu8988s was 98.73%, 95.76%,
69.49%, 33.05% and 0 for ASODM concentrations of 200 μg/ml, 100 μg/ml, 50 μg/ml, 25 μg/ml and 5 μg/ml at 48 hours. Conclusions:
K-ras complementary ASODN can inhibit the growth of human pancreatic cancer cell line PaTu8988s by 30.05% to 98.73%. This
is likely to contribute to the specificity of the K-ras mRNA complementary capped ASODN sequential codon. Non-specific effect
and side effect of ASOND were observed for instance, the greater the concentration is, the earlier the peak of inhibitory
rate is reached. In concentration, of 25 μg/ml to 100 μg/ml ASODN showed a dose-effect correlation. 相似文献
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Haider Samee Zhen-xing Li Hong Lin Jamil Khalid Yong-chao Guo 《Journal of Zhejiang University. Science. B》2009,10(2):147-153
Ethanol extracts of brown seaweeds from Pakistan and China were isolated and compared for their antiallergenic activities.They included Sargassum tennerimum (ST) and Sargassum cervicorne (SC) from Pakistan,and Sargassum graminifolium turn (SG),Sargassum thunbergii (STH),and Laminariajaponica (LJ) from China.The ethanol extracts of these brown seaweeds were optimized at 85% (v/v) ethanol for the maximum yield of phlorotannin,an inhibitor against hyaluronidase.Total phlorotannins contained in the crude extracts were measured as 1.71% (SG),0.74% (STH),0.97% (LJ),3.30% (SC),and 5.06% (ST).The 50% inhibitory concentrations (IC50) of Pakistani SC and ST were 109.5 and 21 μg/ml,respectively,lower than those of Chinese SG,STH,and LJ (134,269,and 148 μg/ml,respectively).An antiallergic drug,disodium cromoglycate (DSCG),had an IC50=39 μg/ml,and a natural inhibitor of hyaluronidase,catechin,had an IC50=20 μg/ml.The IC50 of ST extract was found similar to that of catechin (21 vs 20 μg/ml) and lower than that of DSCG (21 vs 39 μg/ml).This suggests that ST is a potent inhibitor of hyaluronidase,indicating a promising future development of natural antiallergic medicines or functional foods. 相似文献
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Liu P Shen SR Ruan H Zhou Q Ma LL He GQ 《Journal of Zhejiang University. Science. B》2011,12(11):923-930
Naturally fermented pickles harbour many lactic acid bacteria (LAB). Forty-three LAB strains with conjugated linoleic acid
(CLA)-producing ability were isolated from three naturally fermented pickle brines. Of these isolates, lp15 identified as
Lactobacillus plantarum by API 50 CHL system and full-length 16S rDNA sequence analysis exhibited the highest CLA-producing ability (26.1% conversion)
at 48 h in de Man Rogosa Sharpe (MRS) broth in the presence of 100 μg/ml of linoleic acid (LA). Compared to other strains,
L. plantarum strain lp15 showed the highest tolerance upon increased levels of LA in the medium, i.e., up to 600 μg/ml. This strain converted
about 25% of LA into CLA isomers [predominantly cis-9, trans-11 CLA (9-CLA) and trans-10, cis-12 CLA (10-CLA)], of which 75% was 9-CLA. Interestingly, though the conversion rate of LA into CLA by lp15 remained stable
between 100 to 600 μg/ml LA levels in the medium, it dropped sharply at 1000 μg/ml. Taken together, the lp15 strain displayed
relatively high LA tolerance with higher conversion rate, which implies that this strain is a valuable candidate for enhancing
the CLA content in food-sources like pickles. 相似文献
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Antibacterial potency of methanol extracts of three green lower plants, Pneumatopteris afra, Platycerium bifurcatum and Nephrolepsis bisserata was determined using agar dilution method on clinical strains of Escherichia coli, Staphylococcus aureus, Klebsiella spp. and Salmomelia typhi. Antibacterial activities were observed at concentrations of 12.5, 25.0, 50.0 and 100.0 μg/ml. Their minimum inhibitory concentrations ranged from 12.5~100 μg/ml. Extracts of P. afra and P. bifurcatum were most active. Antibacterial activities observed with N. bisserata were less pronounced with no detectable activity at extract con-centrations of 12.5 and 25.0 μg/ml. E. coli, together with S. aureus appeared to be the most susceptible of the test bacteria while Klebsiella spp. was least sensitive. The significance of our findings is discussed. 相似文献
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INTRODUCTION Telomeres are distinctive DNA-protein struc-tures that cap the ends of linear chromosomes.It is very important to keep the chromosomes stabilization.Telomerase activity is closely linked to attainment of cellular immortality,a step in carcinogenesis,while lack of such activity contributes to cellular senes-cence.Telomerase is activated in more than85%ofmalignant tumors(Hiayma et al.,1997).Human te-lomeric repeat binding factor1(TRF1)is a telomere associated with proteins a… 相似文献
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Comparison of high order aberration after conventional and customized ablation in myopic LASIK in different eyes of the same patient 总被引：4，自引：0，他引：4
Purpose: To verify whether there exists any difference in higher order aberrations after undergoing myopic LASIK (laser in situ keratomileusis) with conventional ablation and customized ablation in different eyes of the same patient. Methods: This was a prospective randomized study of 54 myopic eyes (27 patients) that underwent LASIK using the Nidek EC-5000 ex-cimer laser system (Nidek, Gamagori, Japan). Topography-guided customized aspheric treatment zone (CATz) was used in the first eye of the patient (study group) and the other eye of the same patient was operated on with conventional ablation (control group). Higher order aberrations [root-mean-square (RMS) in the 5-mm zone] of both groups were observed with the Nidek OPD-Scan aberrometer before and 3 months after LASIK. Preoperative mean refractive error was similar between two eyes of the same patient (t=?0.577, P>0.05). Results: Preoperatively, higher order aberrations (RMS in the 5-mm zone) in the CATz ablation and conventional groups were (0.3600±0.0341) μm and (0.2680±0.1421) μm, respectively. This difference was not statistically significant (t=1.292, P>0.05). Three months after LASIK, higher order aberrations (RMS in 5-mm zone) in the CATz ablation and conventional groups were (0.3627±0.1510) μm and (0.3991±0.1582) μm, respectively. No statistically significant difference was noted between pre- and postoperative higher order aberrations in the CATz group (t=?0.047, P>0.05). However, a statistically significant increase in higher order aberrations was observed after conventional ablation (t=?5.261, P<0.05). A statistically sig-nificant difference was noted in the increase of higher order aberrations after LASIK between groups (t=?2.050, P=0.045). Con-clusion: LASIK with conventional ablation and topography-guided CATz ablation resulted in the same BSCVA (best specta-cle-corrected visual acuity) 3 month after LASIK. Higher order aberrations were increased, but the increase of higher order ab-errations after customized ablation treatment was less than that after conventional ablation. 相似文献
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Liu Y Zhang CZ Yu XY Zhang ZY Zhang X Liu RR Liu XJ Gong ZM 《Journal of Zhejiang University. Science. B》2007,8(12):900-905
A high affinity polyclonal antibody-based enzyme linked immunosorbent assay （ELISA） was developed for the quantification of zeranol in bovine urine. On the basis of urine matrix studies, the optimized dilution factors producing insignificant matrix interference were selected as 1：5 in pretreatment. In the improved ELISA, the linear response range was between 0.02 and 1 μg/ml, and the detection limit was 0.02 μg/ml for the assay. The overall recoveries and the coefficients of variation （CVs） were in the range of 82%-127% and 3.5%-8.8%, respectively. Thirty-six bovine urine samples spiked with zeranol （ranging from 0.2 to 10 μg/ml） were detected by the ELISA and liquid chromatography （LC） method, and good correlations were obtained between the two methods （R^2=0.9643）. We conclude that this improved ELISA is suitable tool for a mass zeranol screening and can be an altemative for the conventional LC method for zeranol in bovine urine. 相似文献