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根据昆山市蔬菜市场供应与准入的主要做法。针对性地提出了包括加强环节管理、完善监管网络、做好准出准入衔接等方面的蔬菜市场安全准入工作的对策建议。 相似文献
906.
杨梅雌、雄种质遗传关系的RAPD和ISSR分析 总被引:2,自引:0,他引:2
为获得与主栽的杨梅品种遗传基础相近的杨梅雄株,文章采用了22个多态的RAPD引物和7个多态的ISSR引物,对浙江杨梅的栽培品种东魁、荸荠种、晚稻杨梅、丁岙梅和早色等10个雌株与17个雄株种质资源间的遗传关系进行了研究。结果表明,不同杨梅产地收集的这17个杨梅雄株种质资源中,雄株与品种间的遗传关系呈规律性,即同一产区的地方品种与当地的雄株间遗传相似程度最高,而同一地区不同雄株与当地主栽品种间的遗传相似程度也有不同。通过UPGMA法进行聚类分析,上述5个杨梅主栽品种分别获得了与其亲缘关系相对接近的雄株,成对遗传相似系数最高为0.958,最低为0.878。 相似文献
907.
ZHU Jun-hui JIN Ming QIU Hao ZHANG He-liang MA Wei XIAO Xuan LI Chen-song LUO Zhao-yang ZHANG Zhi-wei 《园艺学报》2018,34(5):925-929
AIM:To observe the expression of calreticulin (CRT) in nasopharyngeal carcinoma tissues, analyze the significance of clinical pathology and the influence on epithelial-mesencymal transition (EMT) of CNE2 cells. METHODS:The expression of calreticulin was detected by immunohistochemistry in 52 nasopharyngeal carcinoma and 57 nasopharyngeal benign tissues, and the significance of clinical pathology was evaluated. The calreticulin gene-specific small interfering RNA was constructed, and then was transfected into the NPC cell line CNE2 using the cationic liposome method. The effect of CRT on the morphological changes of the CNE2 cells was observed under light microscope. The effect of CRT on the cell migration and invasion abilities of the CNE2 cells was detected by Transwell migration and invasion assays. The expression of EMT-related proteins E-cadherin, vimentin, transforming growth factor (TGF)-β and matrix metalloproteinase (MMP)-9 in the CNE2 cells was determined by Western blot. RESULTS:The positive expression rate of CRT in the benign lesion tissues was 19.29% (11/57), which was significantly increased in the nasopharyngeal carcinoma tissues as 82.69% (43/52). The expression rate of CRT was positively correlated with the stage of nasopharyngeal carcinoma and lymph node metastasis (P<0.05). Knockdown of CRT expression made the CNE2 cells showing a spindle shape to a flat, cobblestone-like epithelial state change, arranged more compact, and the migration and invasion abilities were significantly decreased (P<0.05). Knockdown of CRT expression resulted in significant increase in the protein expression of E-cadhe-rin, and the decreases in the protein expression of vimentin, TGF-β and MMP-9 in the CNE2 cells (P<0.05). CONCLUSION:Calreticulin expression in nasopharyngeal carcinoma is significantly higher and positively correlated with nasopharyngeal carcinoma stage and lymph node metastasis. Calreticulin promotes cell migration and invasion of nasopharyngeal carcinoma CNE2 cells by inducing EMT. 相似文献
908.
AIM: To investigate the characteristic of T-cell acute lymphocytic leukemia 1 (TAL1) gene expression in acute myeloid leukemia (AML) cell lines and in primary AML cells from de novo AML patients with different subtypes. METHODS: Real-time PCR was used to determine the expression of TAL1 mRNA in acute leukemia cell lines (Jurkat, CCRF-CEM, HL-60 and NB4 cell lines) and peripheral blood mononuclear cells from 47 newly diagnosed AML patients. Twelve healthy individuals were served as healthy control group. RESULTS: A significantly increased level in TAL1 mRNA was found in AML cell lines (HL-60 and NB4), T-cell acute lymphacytic leukemia (T-ALL) cell lines (Jurkat, CCRF-CEM) and primary AML cells compared with the healthy controls. Over-expression of TAL1 was found in all detected AML subtypes, the highest level of TAL-1 mRNA was found in AML-M1 and AML-M5 subtype (P<0.05). CONCLUSION: High expression of TAL1 in AML might influence the differentiation and proliferation of myeloid cells, further investigation needs to confirm whether it would be as a biomarker for pathogenesis of AML. 相似文献
909.
Cysteine-rich angiogenic inducer 61 (Cyr61/CCN1) is an extracellular matrix-associated signaling protein consisting of 381 amino-acid residues, which has the regulatory function for a multitude of cellular responses. The pleiotropic effects of CCN1 on the initiation and resolution of inflammation as well as oncogenesis and development of tumor were reported. According to the numerous data from experimental and clinical studies, this article provides an overview on CCN1 and summarizes the latest understanding of the role of CCN1 in pulmonary diseases. 相似文献
910.
AIM:To explore the effect of L-glutamine (Gln) on obesity and insulin resistance in high-fat diet(HFD)-induced C57BL/6J mice. METHODS:Male C57BL/6J mice (n=60) were randomly divided into normal control (NC) group, HFD group, HFD+L-alanine (Ala) group and HFD+Gln group. Each group had 15 mice. The body weight of the mice was recorded weekly. Fasting blood glucose (FBG) of the mice was tested after 12-h fasting only with water-drinking at the end of the 16th week. The mice were sacrificed and epididymal fat pad was measured. The levels of insulin (INS), leptin (LEP), adiponectin (APN) and glucagon-like peptide-1 (GLP-1) were measured by ELISA. The insulin resistance index (IRI) and insulin sensitivity index (ISI) were calculated. RESULTS:Compared with NC group, the body weight, epididymal fat pad weight, and the levels of FBG, INS, IRI and LEP increased significantly in HFD group (P<0.05), while the levels of ISI and APN decreased significantly (P<0.05). Compared with HFD group, the body weight, and the levels of FBG, IRI and LEP decreased significantly in HFD+Gln group (P<0.05), while the levels of ISI and APN increased significantly (P<0.05). No significant difference of serum GLP-1 levels the four groups was observed. CONCLUSION:L-glutamine reduces the body weight and attenuates the insulin resistance of HFD-induced mice. 相似文献