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291.
近年来,随着直播稻种植面积不断扩大和栽培技术不断改革,田间草相也随生态条件的不同而发生了变化。水稻前期干、湿栽培,十分有利老草复活和新草的萌发生长。直播稻田杂草危害已成为阻碍直播稻优质高产和大面积推广应用的主要障碍。为了明确直播稻田杂草的生态特点和杂草萌发规律,科学制定防除策略,积极探索直播稻田杂草的化除技术,安全、有效、经济地将杂草危害损失控制在最低限度,我们于2003年开展了直播稻田杂草的生态特点和防除技术研究,初步摸清直播稻田出草规律,得出化除配套技术,并进行了大面积推广应用,取得了显著的灭草、增产效果… 相似文献
292.
WU Bin CAI Xiao-chang ZENG Yao-ying SHI Jun WANG Tong ZHAO Jing-xian HUANG Xiu-yan 《园艺学报》2005,21(5):931-935
AIM: To explore the inhibitory effect of oxymatrine (OMT) on the allergic contact dermatitis (ACD) stimulated by dinitrofluorobenzene (DNFB) and its effects on the proliferation of the lymphocytes. METHODS: ① An ACD mouse model was established by stimulation with DNFB, and then the mice were injected intraperitoneally with different dosages of OMT, PBS and hydrocortisone (HCT) respectively, the swelling degree of their auricles was examined. ② Carboxyfluorescein diacetate, succinimidyl ester (CFDA-SE) dye and flow cytometer were used to examine the fluorescence intensity changes of lymphocytes stimulated by polyclonal stimulator ConA and OMT. RESULTS: ① compared with PBS group, OMT possessed the strong inhibitory effect on the ACD caused by DNFB in a dose-dependent manner, and its inhibitory effect was equivalent to the HCT of the same dosage with fewer side effects. ② In vitro experiments proved that OMT (500, 125 and 31 mg/L) had the ability to restrain the proliferation of lymphocytes of mouse. CONCLUSION: OMT possesses an inhibitory effect on the ACD induced by DNFB, and OMT is a kind of immunosuppressor. 相似文献
293.
WANG Zhi-jian DING Wen-hui SHI Li-bin MENG Lei REN Zi-wen PU Ding-fang ZHANG Yong-gang TANG Chao-shu 《园艺学报》2005,21(11):2081-2085
AIM: To investigate the expression of the urotensin Ⅱ (UⅡ) receptor GPR14 in the aorta of apoE knockout mouse. METHODS: The expression of GPR14 in the aorta of apoE knockout C57BL/6J mice at various ages (18 weeks, 28 weeks, and 38 weeks old, respectively) was determined with competitive RT-PCR. A binding assay of [125I]-UⅡ on the aortic tissue was also performed in 28 weeks group. RESULTS: We found significant upregulation of GPR14 mRNA at all three ages. Compared with wild type group at the same age, the GPR14 mRNA level in apoE knockout mice increased 54.2% in 18 week group (P<0.05), 50.0% in 28 weeks group (P<0.05) and 97.0% in 38 weeks group (P<0.01). In the knockout group or in the wild type group, expressions of GPR14 in the 28 weeks time point were significantly higher than that in other two age groups, and there was no difference between the 18 weeks and 38 weeks group. In the binding assay, the Bmax of [125I]-UⅡ to the aorta of apoE knockout mouse at 28 weeks increased 64% compared with the wild type (P<0.01), and no difference about the Kd between the two groups was observed. CONCLUSION: UⅡ and its receptor probably play an important role in the development of atherosclerosis. 相似文献
294.
SHI Dun-yun ZHANG Qiong-li LI Yu-zhu LI Ming XU Yun ZHUO Jia-cai DU Xin WANG Ming-chun 《园艺学报》2005,21(11):2264-2267
AIM: To explore the characters of fibroblast-like (F-L) cells cultured from granunocyte clony stimunating factor (G-CSF)-mobilized peripheral blood cell (PBC) harvests. METHODS: The adherent cells in the PBC harvests were cultured for 2 week in the mediums of RPMI-1640/L-DMEM/G-CSF or interleukin-3 (IL-3) plus RPMI-1640, the cultured F-L cells were analyzed by flow cytometry (FC). RESULTS: The adherent non-confluent F-L cells obtained from the four groups were similar in their phenotypes: CD33+, CD11c+, CD64+, CD14+, CD45+, HLA-DR+, CD86+, CD34-, CD38-, CD3-, CD19-, CD56-, CD29-, CD44-, CD105-. The F-L cells are similar to monocytes except CD38- and were distinct from dendritic cells (DC) or mesenchymal stem cells (MSC). CONCLUSION: The cultured F-L cells are macrophages rather than DC or MSC. G-CSF, rhIL-3 enhances their numbers. 相似文献
295.
AIM: To study the effects of intrathymic inoculation of liver specific antigen (LSA) on hepatocyte apoptosis after liver allotransplantation. METHODS: Orthotopic liver transplantation was used in this study. Group Ⅰ: syngenic control (Wistar-to-Wistar); Group Ⅱ: acute rejection (SD-to-Wistar); Group Ⅲ: thymus inoculation of SD rat LSA day 7 before transplantation. The observation of general situation and survival time, hepatocyte apoptosis and LAT expression in liver transplants were used to analyze immune state of animals in different groups. RESULTS: The general situation of group Ⅰ was very well after transplantation. Recipients of groupⅡ lost body weight progressively and all died within day 9 to day 13 post transplantation. As for group Ⅲ, the general situation of recipients was remarkably better than that in group Ⅱ. The positive cells of apoptosis in group Ⅲ detected by TUNEL were not significantly different from that in group Ⅰ, but was significantly lower than that in group Ⅱ. LAT was detected at any time in group Ⅱ with peak expression at day 5 and day 7 post transplantation. In contrast, LAT was not detected in any other groups. CONCLUSION: Intrathymic inoculation of LSA protects hepatocytes from apoptosis after liver allotransplantation. 相似文献
296.
297.
将吸血诱导的亚洲璃眼蜱唾液腺差异表达基因GP29的开放性阅读框插入pGEX-4T-1,转化BL21,表达出一相对质量为53ku的蛋白,其大小与预计结果一致。蛋白质的肽质量图谱和“1381.7511”肽段序列两方面的结果证明,SDS-PAGE胶板上相对质量为53ku的蛋白就是由目的基因表达的GST融合蛋白。该蛋白与Swiss PROT库中的任何蛋白均有较大差别,可能是一个新功能分子。 相似文献
298.
299.
300.
In order to obtain Enterococcus faecalis from fur animals and evaluate its prebiotic properties,in this study,Enterococcus faecalis was isolated from the feces of healthy adult fur-bearing animals (mink,fox,raccoon dog),identified by morphological observation,biochemical test and 16S rRNA sequence analysis.The growth curve,acid production capacity and antibiotic sensitivity of the Enterococcus faecalis isolates were measured to evaluate their probiotic properties.Some strains were selected to determine their tolerance to temperature,artificial gastric juice and artificial bile salt.The results showed that five strains were Gram-positive,and their biochemical characteristics were basically consistent with the standard strains of Enterococcus faecalis,and they were identified as Enterococcus faecalis by 16S rRNA sequence analysis.The five strains all entered the logarithmic phase at 2 h after culture,and entered the stable phase at 8-10 h,and had weak acid production capacity.The resistance rate of the isolates to tetracycline and levofloxacin was 100%,followed by penicillin (80%),erythromycin (80%),gentamicin (80%) and chloramphenicol (40%).All the isolates were sensitive to ampicillin and vancomycin.Enterococcus faecalis from mink,fox and raccoon dog had strong tolerance to temperature below 60 ℃,artificial gastric juice with pH>3.0 and 0.3%-0.5% concentration of bile salt,but poor tolerance to temperature above 70 ℃,and artificial gastric juice with pH<3.0.In conclusion,five strains of Enterococcus faecalis from fur animals (mink,fox,raccoon dog) were obtained in this study.The isolated strains propagated rapidly,which were suitable for colonization and played a prebiotic role in fur animals' intestines,and had good prebiotic characteristics and stress resistance.They could be used as candidate strains for animal microbiological agents for further study. 相似文献