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991.
甘蓝抗重金属污染的研究 总被引:4,自引:0,他引:4
在被重金属污染的土壤中 ,用Ca(NO3)2 拌种处理甘蓝种子 ,进行甘蓝抗重金属污染试验。结果表明 ,Ca(NO3) 2 拌种可以促进甘蓝种子萌发和幼苗生长 ,增强光合速率和抗逆性 ,使甘蓝叶片中Hg ,Cr,Cd含量分别比对照下降 71.9%~ 97.7% ,2 .77%~ 12 .88% ,38.4 6 %。 相似文献
992.
Hu Q Pan Z Deen S Meng S Zhang X Zhang X Jiao XA 《Veterinary immunology and immunopathology》2007,120(3-4):223-233
Chinese native chicken breeds provide useful resources for the study of genetic diversity. In this study, the alleles of CD8 alpha and CD3d cDNA from Chinese native and introduced western breeds of chicken were analyzed at the sequence level. Six alleles were found, due to 13 amino acid replacements in the extracellular domain of the CD8 alpha sequence. There were four alleles detected in the Chinese strains, and alleles 5 and 6 were identified for the first time. Allele 6 was shared by Langshan, Beijing Fatty and Recessive White Feather chickens. Allele 2, found in the Bigbone strain, was the same as that found in the Leghorn strain H.B15.H7, and allele 3 in the Xianju breed was also the same as in the Leghorn strain H.B15.H12. Two Leghorn lines (RPL line 7 and AY519197) and the Camellia possessed an allele (alleles 1, 4 and 5), respectively, that was not found in the other lines. Nine out of 13 amino acid replacements were situated in the putative major histocompatibility complex (MHC) class I binding CDR1 (positions 30, 33 and 34), CDR2 (positions 58, 62, 63 and 65) and CDR3 (positions 90 and 106). Except for the Xianju breed, the CD8 alpha cDNA of Chinese native chicken breeds shared high homology. Two alleles were found in CD3d. Three additional nucleotides were found at positions 64, 65 and 66 in the newly discovered allele 2. This led to a difference of four amino acids (at residues 22, 23, 24 and 25) in the extracellular domain of CD3d cDNA from the Gushi, Recessive White Feather and ISA chickens compared with these of the White Leghorn and T11.15 (NM_205512). Five hybridoma clones (1C9, 1H5, 4B11, 6G5 and 13C5) against chicken CD8 alpha were generated by DNA immunization. Two monoclonal antibodies (mAbs), 6G5 and 4B11, showed reactivity to the splenocytes from five Chinese native chicken breeds, the Recessive White Feather chicken and the Leghorn (AY519197), while mAbs 1C9, 1H5 and 13C5 showed no reaction with these breeds. 相似文献
993.
AIM: To investigate the effects of gonadotropin-releasing hormone (GnRH) analogue on the growth of breast cancer cell lines MCF-7 and MDA-MB-231 in vitro and to explore the related mechanisms with PI3K/Akt or ERK/MAPK pathways. METHODS: The proliferation of human breast cancer cell lines MCF-7 and MDA-MB-231 treatment with triptorelin was detected by MTT assay and the distribution of the cell cycle was determined by flow cytometry. The phosphorylation of the ERK1/2 and Akt was evaluated by Western blotting. RESULTS: Triptorelin inhibited the proliferation of MCF-7 cells at concentration of 10-5 mol/L after treated for 192 h or at concentration of 10-4 mol/L after treated for 168 h and 192 h. Triptorelin inhibited the proliferation of MDA-MB-231 cells at concentration of 10-4 mol/L after treated for 192 h (P<0.05).Treatment with triptorelin for 192 h at concentration of 10-4 mol/L had no statistical significance effect on phosphorylation of ERK1/2 and Akt(P>0.05).CONCLUSION: Inhibitory effect of GnRH analogue triptorelin on human breast cancer cells is not just the connection with the down-regulation of pituitary hormone, but also a direct inhibitory effect. The role may not be involved in the activation of ERK/MAPK and PI3K/Akt signaling pathways. 相似文献
994.
AIM: To study the effect of hsa-miR-218 on cervical cancer HeLa cell growth and the underlying molecular mechanism.METHODS: The lentivirus expression vector pmiR-218 targeting to hsa-miR-218 was constructed. pmiR-218 was transfected into HeLa cells. The number of viable HeLa cells was counted by the method of Trypan blue exclusion. The inhibitory rate of cell activity was detected by WST-8 assay. The expression of LIM and SH3 protein 1(LASP1) at mRNA and protein levels was determined by real-time PCR and Western blot. The interaction between miR-218 and LASP1 was examined using a luciferase reporter assay.RESULTS: The lentivirus expression vector pmiR-218 targeting to hsa-miR-218 was constructed successfully and confirmed by DNA sequencing. Over-expression of miR-218 inhibited the activity of HeLa cells with the inhibitory rates of 15%, 26% and 65% at 24 h, 48 h and 72 h, respectively. The difference between transfection group and blank control/negative control group was statistically significant. The luciferase activity was reduced when co-transfection with miR-218 mimics and LASP1-3,UTR plasmid. The relative expression of miR-218 was increased after transfection with pmiR-218. Over-expression of miR-218 down-regulated the LASP1 expression at mRNA and protein levels by 25% and 75% respectively. Compared with blank control group and negative control group, the difference was statistically significant(P<0.05).CONCLUSION: pmiR-218 effectively inhibits the growth of HeLa cells in a time-dependent manner. miR-218 targets to the 3,UTR of LASP1, thus down-regulating the expression of LASP1 in HeLa cells. 相似文献
995.
CHANG Cheng JIN Peng ZHENG Wei KANG Hua-li DENG Meng-yang LI Shuang-fei WU Xiao-jing 《园艺学报》2015,31(1):12-17
AIM: To study the expression of Jagged2/Notch3 signaling molecules in pulmonary vascular wall of pulmonary hypertensive rats induced by monocrotaline. METHODS: SD rats were randomly divided into normal control group (C group,n=15), solvent control group (S group,n=15) and monocrotaline model groups (M group,n=15). The model of pulmonary hypertension was established by a single subcutaneous injection of monocrotaline (50 mg/kg). The rats in S group were given a single subcutaneous injection of the same dose of solvent. After 4 weeks, the pulmonary vascular remodeling was assessed by HE staining, and the mean pulmonary artery pressure (mPAP) and right ventricular systolic pressure (RVSP) were determined by right heart catheterization. The expression of Jagged2/Notch3/Hes5 molecules in the pulmonary vascular wall was detected by immunohistochemical method and real-time PCR. RESULTS: Compared with S group and C group, the percentage of medial wall thickness of smaller arteries in model group increased significantly (P<0.01). The levels of mPAP and RVSP in M group were significantly higher than those in S group and C groups (P<0.01). The results of real-time PCR showed that the expression of Jagged2, Notch3 and Hes5 was significantly increased in M group compared with S group and C group. The data from immunohistochemical detection indicated that Jagged2 mainly expressed in the intima of small lung artery, Notch3 and Hes5 mainly expressed in the medial smooth muscle cells. Compared with S group and C group, the expression of Jagged2 and Notch3 was significantly increased in the lung small arteries of M group. CONCLUSION: The activation of Jagged2/Notch3 signaling pathway might play an important role in the formation of pulmonary hypertension. 相似文献
996.
997.
磷化氢环流熏蒸技术在高大房式仓中的应用 总被引:2,自引:0,他引:2
在高大房式仓中进行了磷化氢环流熏蒸试验,同时研究了不同仓型和不同熏蒸方式存在的差异。结果表明,在仓房容量、风道设置、环流设置配置合理的条件下,能在较短时间内使磷化氢气体在仓内各部位分布均匀,最低浓度与最高浓度比值最小为0.5,大部分比值在0.8-0.9之间,均高于国外资料推荐的PH3环流熏蒸浓度均匀性标准,即大于0.25。保持有效杀虫浓度的时间长,能够杀死仓内粮堆中的储粮害虫,取得了良好的杀虫效果。 相似文献
998.
A.?F.?Tjin?Wong?Joe R.?W.?Summers G.?D.?Lunn M.?D.?Atkinson P.?S.?KettlewellEmail author 《Euphytica》2005,143(3):265-269
In 1998 and 1999 the UK winter wheat variety Rialto produced unexpected low Hagberg falling numbers that could not be directly linked to sprouting. It was proposed that these reductions in quality could be due to pre-maturity α-amylase activity (PMAA). The problem was not identified during the selection and commercial development stages. Our study tested the hypothesis that the variety Rialto is PMAA-susceptible. Analysis was done on 13 year-location combinations of field grown Rialto. Together, visual and chemical assessments of sprouting and iso-electric focusing of α-amylase isozymes identified several samples with significant α-amylase activity in the apparent absence of sprouting. In addition, tests with α-amylase sensitive Phadebas gel revealed distinctive PMAA discoloration patterns in 10–44% of the grain from the 13 samples, leading to the conclusion that Rialto is PMAA-susceptible. Diurnal temperature range accumulated for an 11 day period during a warm spell in early simulated grain development displayed a significant but negative correlation with the number of grains showing clear PMAA discoloration patterns on Phadebas gel. The number of clear PMAA grains correlated positively with rainfall accumulated over 11 days. These results suggest that PMAA can increase under conditions similar to those conducive to pre-harvest sprouting. It is however also possible that in some instances both PMAA and incipient sprouting could have produced similar patterns of α-amylase activity. In addition to tests with Rialto, Phadebas gel tests were therefore also done with the known high Hagberg varieties Option and Malacca, sprouted in a controlled environment. Results from the additional gel tests suggest that visual and chemical assessments of sprouting in the grain combined with Phadebas gel analysis could identify PMAA more reliably in grain sub-samples than Phadebas gel analysis alone. 相似文献
999.
Elizabeth Keep 《Euphytica》1985,34(2):509-519
Summary In black currant (Ribes nigrum) backcross progenies segregating for resistance to the gall mite, Cecidophyopsis ribis
Westw. (gene Ce from Ribes grossularia L.), and to American gooseberry mildew, Sphaerotheca mors-uvae (Schw.) Berk. (gene Sph
3from R. glutinosum), significant differences in season of leafing out occurred between the resistant and susceptible classes. The data are consistent with the hypothesis that two additive genes, Lf
1and Lf
2, controlled season of leafing out and that Ce and Sph
3 were linked with Lf
1. 相似文献
1000.