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41.
Summary Aseptically cultured shoots of Chinese gooseberry exhibited growth disorder and morphological aberrances, and some died after being exposed to sufficient gamma-ray irradiation. The death rate was dose dependant and the LD50 was 80–90 Gy and 50–60 Gy respectively for cv. Hayward and clone 4. All petiole explants irradiated with gamma-ray could form calli as the control, but the rate of differentiation of adventitious shoots of the petiole explants decreased and was dependant on dose. Sensitivity of the shoot or petiole explants to gamma-ray irradiation varied with species. Gamma-ray irradiation did not deter either the 2-node segments from producing axillary shoots M1, M2, and M3 or the advantitious shoots originating in the petiole explants and the M3 shoots from forming advantitious roots. Therefore, using aseptically cultured axillary or adventitious buds for mutation breeding of Chinese gooseberry is feasible. A bacterium surviving in the explants lessened the efficiency of these two in vitro techniques in mutation breeding of Chinese gooseberry.Abbreviations IAA
3-indole acetic acid
- IBA
-indole butyric acid
- MS
Murashige & Skoog (1962) 相似文献
42.
春冠亲本之一493是将国外引进的资源96011、9502杂交后,经系统选育,采用露地越冬栽培加大耐先期抽薹性的选择强度选育出的自交不亲和系。另一亲本711是从国外引进的资源B-21经多代自交选育出的自交不亲和系。该品种耐寒,露地越冬不易先期抽薹,早熟,叶球尖桃形,肉质脆嫩,品质佳。单球质量1.5kg左右,每667m^2产量3500kg左右。在南方地区可露地越冬栽培,已在长江流域示范推广。 相似文献
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AIM:To explore the effects of oxidized low density lipoprotein (OxLDL) and one of its component— lysophosphatidylcholine (LPC) on cholesterol efflux from mouse macrophage foam cells.METHODS:(1) Cholesterol efflux induced by apoAI from mouse peritoneal macrophage foam cells loaded with OxLDL or acylated LDL(AcLDL) was measured. (2) Cholesterol efflux induced by LPC and apoAI from macrophage foam cells separated from normal or apoE gene deficient (E0) mouse loaded with AcLDL were measured.RESULTS:(1) When the macrophage foam cells were incubated with apoAI, cholesterol efflux from AcLDL-induced macrophage foam cells increased significantly compared to that of OxLDL-induced macrophage foam cells. (2) LPC promoted cholesterol efflux from macrophage foam cells in relation to both dosage and time. When LPC was incubated with E0 mouse macrophage foam cells, the released cholesterol mass was significantly lower than that of normal mouse macrophage foam cells. It was also found that cholesterol efflux induced by apoAI normally occurred in E0 mouse macrophage foam cells.CONCLUSIONS:(1) OxLDL accumulated cholesterol in macrophages and impair cholesterol efflux. (2) LPC induced cholesterol efflux from macrophage foam cells, which may occur via apoE pathway. 相似文献
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AIM: To study the electrophysiological characteristics of ion channels of stem cell derived cardiomyocytes(SCDC) of mouse. METHODS: Embryonic stem cells of D3 line(ES-D3) were cultured on the MEF feeder layer with BRL conditioned medium, and fetal mouse heart cells(FMHC)were cultured in vitro. Then ES-D3 cells were induced to differentiate into many kinds of cells. SCDC were harvested on day 12 after differentiation initiating and identified by electro-microscope and immunocytochemistry. SCDC and FMHC were prepared for the patch-clamp research. Sodium and calcium currents together were elicited and compared between SCDC and FMHC. RESULTS: The current characteristics of sodium and calcium channels of SCDC were very similar to FMHC. CONCLUSION: The functional expression of ion channels occurred during ES-D3 cells differentiation and the electrophysiological characteristics of sodium and calcium channels of SCDC are very similar to FMHC. 相似文献