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991.
992.
Li-Wang Liu Yan Wang Yi-Qin Gong Tong-Min Zhao Guang Liu Xiao-Yan Li Fan-Min Yu 《Scientia Horticulturae》2007
Three DNA molecular marker systems, RAPD, ISSR and SSR, were used to test seed genetic purity of two commercial hybrid tomato (Lycopersicon esculentum L.) cultivars ‘Hezuo 903’ and ‘Sufen No. 8’. Genomic DNA from the two F1 hybrid cultivars and their corresponding parental lines was screened with 218 RAPD decamer primers, 54 ISSR primers and 49 SSR primers. Among the 321 primers, 4 primers for ‘Hezuo 903’ and 3 for ‘Sufen No. 8’, which could produce both female and male parent-specific markers, were selected for testing the genetic purity. A total of 210 hybrid individuals of each cultivar were analyzed using the identified primers. The combined results of the marker analysis showed that eight of the 210 F1 plants in ‘Hezuo 903’ and 13 of 210 in ‘Sufen No. 8’ were false hybrids, and the overall genetic purity of the two F1 hybrid seed lots was 96.2 and 93.8%, respectively. This study showed that RAPD and SSR markers could provide a practical and efficient tool in quality control of the tomato commercial hybrid seeds. 相似文献
993.
XIA Yong ZHANG Yong LI Dong-ye LIN Li XU Rui-jin YU Hao DING Ru-yue YANG Yu CHEN Qing-zhi 《园艺学报》2007,23(1):49-52
AIM: To investigate the effects of celecoxib, a selective cyclooxygenase-2 inhibitor, on antioxidative capability and apoptosis of cardiac myocytes after myocardial infarction. METHODS: 24 New Zealand rabbits were divided into three groups randomly (8 in each group): sham-operated group (sham group), myocardial infarction group (MI group), celecoxib group (Cele group, 10 mg kg-1·d-1, qd, with the drugs gastric gavage for six weeks). The NO concentration, total antioxidative capability (T-AOC), the activity of constitutive nitric oxide synthase (cNOS) and inducible NOS (iNOS) in cardiac tissue homogenate, adjacent to the infracted area, were detected. The pathological changes were observed by light microscope and electron microscopy. The expressions of Bcl-2 and Bax protein in myocytes were observed using immunohistochemistry, and the degree of apoptosis were examined by TUNEL. RESULTS: Cardiac tissue in MI group presented interstitial edema, fibroplastic proliferation, inflammatory cellular infiltration, and vacuolar degeneration in cardiac myocytes. The results of electron microscopy showed that myocytes presented more changes caused by ischemic injury: widened interspace of myofibril, disordered myofibrillae, focal lysis of myofilament, ectasia of sarcoplasmic reticulum. In Cele group, the pathological changes were light, the NO-2/ NO-3 concentration, the activity of iNOS were lower (P<0.05), while the activity of cNOS and T-AOC were higher (P<0.05) than those in MI group. The expression rate of Bcl-2 protein in Cele group was higher than that in MI group, while the Bax was lower (P<0.01). The number of apoptotic myocytes was lower than that in MI group (P<0.01).CONCLUSION: Celecoxib decreases the number of apoptotic cardiomyocytes and increases the antioxidative capability after myocardial infarction. 相似文献
994.
MOU Bo YANG Zhi-hong ZHAO Jia-wei WANG Xuan-chun DONG Xue-hong LIU Yu HU Ren-ming 《园艺学报》2007,23(5):888-892
AIM: To verify and localize the expression of nicotinamide N-methyltransferase (NNMT) in pancreas of streptozotocin(STZ)-induced diabetic monkeys and understand its important role in β-cell destruction in the pathogenesis of diabetes. METHODS: Through an olig-microarray gene chip, NNMT was identified as the most obviously up-regulated genes in pancreas of STZ-induced diabetic monkeys versus controls. Semiquantitative RT-PCR and Western blotting were performed to verify the differential expression at mRNA and protein level respectively. Then the cellular localization of NNMT expression within pancreas was identified by immunohistochemical(IHC) staining.RESULTS: An obvious high expression of NNMT at both mRNA and protein levels was shown in pancreas of STZ-induced diabetic monkeys compared to that of controls. Further localization of the protein by IHC staining in pancreas specimens showed that its altered expression was restricted to central islets, most of which were β cells.CONCLUSION: Expression of NNMT is increased in islets of STZ- induced diabetic monkeys, which infers that NNMT might participate in the process of β cell damage in diabetes probably through the mechanism of energy metabolism disturbance. 相似文献
995.
AIM: To investigate the effect of neuropeptide Y (NPY) on intracellular free calcium([Ca2+]i) and Ca2+ sarcoplasmic reticulum of cardiomyocytes in rats.METHODS: Cardiomyocytes of neonatal Sprague-Dawley rats were incubated with NPY at concentration of 100 nmol/L for 24 h. Fluorescent indicator Fluo-4 AM was used to detect [Ca2+]i and Fluo-5N AM was used to detect Ca2+ in sarcoplasmic reticulum (SR). Calcium image was recorded by laser scanning confocal microscope. The SR Ca2+ load was estimated by caffeine-induced Ca2+ transient (CCT). RESULTS: 24 h after incubation with NPY, compared with control group, the concentration of [Ca2+]i was significantly elevated (P<0.05), and the concentration of free Ca2+ in SR ([Ca2+]SR) was significantly decreased (P<0.05), and the peak of CCT was attenuated.CONCLUSION: Stimulation with NPY for 24 h causes redistribution of free calcium in rat cardiomyocytes, namely the elevation in [Ca2+]i and decline in [Ca2+]SR. 相似文献
996.
WU Quan XIAO Xiang-qian LIU Shu-ye LIU Yu SHI Jian-dang WANG Ke-ming ZHANG Ju 《园艺学报》2007,23(7):1382-1387
AIM: To characterize the effect of estradiol on proliferation, differentiation and extracellular matrix (ECM) accumulation in stromal cells through regulation of BPH-1 paracrine. METHODS: BPH-1 cells were stimulated with different concentrations of estradiol. Conditioned media (CM) were harvested and their effects on stromal cell cultures were tested. Cell proliferation was determined by MTT assay. mRNA of smoothelin, fibronectin, collagen Ⅳ and transforming growth factor β1(TGF-β1) were analyzed by real-time RT-PCR. Western blotting was used to determine smooth muscle myosin heavy chain (SMMHC). ELISA and radioimmunoassay were respectively used to measure fibronectin, TGF-β1 and collagen Ⅳ protein expressions.RESULTS: Estrodiol stimulated the expression and secretion of TGF-β1 in BPH-1 cells. The proliferation of stromal cells increased when they were cultured with CM harvested from estrogen treated BPH-1 cells. The mRNA levels of collagen Ⅳ and smoothelin increased in stromal cells treated with CM from BPH-1 cells. The results of radioimmunoassay also showed that the collagen Ⅳ protein level up-regulated in the supernatants and cell extracts of CM-treated stromal cells. A neutralizing antibody to TGF-β1 inhibited the stimulation of collagen Ⅳ and SMMHC by BPH-1 CM. The expression of fibronectin was only marginally changed in stromal cells cultured in the presence of BPH-1 CM. CONCLUSION: The BPH-1 cells increase ECM accumulation and differentiation of stromal cells through TGF-β1. Estradiol stimulate differentiation of stromal cells by induction of TGF-β1 expression. Estradiol stimulate proliferation by influencing the factors secreted from prostatic epithelial cells. 相似文献
997.
AIM: To observe the targeting thrombolytic effect of a monoclonal antibody specific for cross-linked fibrin connected with liposomal urokinase(UK) in the model of rabbit artery thrombosis.METHODS: Preparation of thrombolytic solutions: with the method of controllable dialysis eradicator in liposomat,empty liposomes,liposomally entrapped urokinase and liposomally entrapped urokinase linked with D-dimer antibody were made.Experiment in vivo: a rabbit thrombosis model of abdominal aorta was induced by ferric chloride.When the blood pressure fall to the lowest,5 different solutions were separately imported (PBS,maximal-level UK,Ab/Lip/UK,Ab/UK-Lip,Ab-UK-Lip) and observed for 40 min continuously.RESULTS: The varieties of 5 groups blood pressures were analyzed with q-test.Significant differences were observed among Ab-UK-Lip group,maximal-level UK group and others (P<0.01).There were marked differences between Ab-UK-Lip group and others in wet weight of thrombuses (P<0.05).However,the quantity of UK in Ab-UK-Lip group was 1/3 of that in maximal-level of UK group.CONCLUSION: The thrombolytic effect on Ab-UK-Lip group is similar to that on maximal-level of UK group,but the dosage of UK is less,and the side-effect is light.This shows,as a homing-device of liposomal urokinase,the D-dimer antibody has targeting effect and the agent of Ab-UK-Lip will be attached importance by-and-by. 相似文献
998.
999.
应用于作物体细胞杂种鉴定的遗传标记方法 总被引:1,自引:0,他引:1
着重介绍了4类遗传标记方法的原理及特点,简要概述了其在作物体细胞杂种鉴定方面的应用进展. 相似文献
1000.
高温胁迫下冷季型草坪草的耐热性评价 总被引:6,自引:0,他引:6
对5个典型冷季型草坪草品种在海南进行耐热性试验.在大田高温胁迫环境下,草坪草热害症状最初表现为叶片发生萎蔫,生长率减缓或停滞,但其是否受害却最先反映在叶片灼伤率上,受害最终表现为草坪盖度和根系生长量的下降.叶片灼伤率是判断草坪草早期是否受到热伤害最敏感的指标.耐热性评价结果:Pacer高羊茅Festuc atundincea cv.Pacer>Houndog高羊茅F.arundinacea cv.Houndog>Merit草地早熟禾Poa pratensis cv.Merit>Derby黑麦草Lolium pernne cv.Derby>Cobra匍匐翦股颖Agrostis palustris cv.Cobra.28~36 ℃可认为是冷季型草坪草的临界受害温度区间,28~32 ℃为初始受害温度区间,32~36 ℃为致死温度区间. 相似文献