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111.
Casey L. Donnelly MS Christophe Staub PhD Dickson Varner PhD DVM Terry Blanchard PhD DVM Larry Johnson PhD David W. Forrest PhD 《Journal of Equine Veterinary Science》2007,27(5):212-216
Apoptosis is necessary for both initiation and control of spermatogenesis; however, an increase in apoptosis can lead to subfertility/infertility in stallions, causing substantial financial loss in the equine industry. The ability of stem cell factor (SCF), leukemia-inhibiting factor (LIF), granulocyte–macrophage colony-stimulating factor (GM-CSF), and estradiol (E2), alone or in combination, to prevent apoptosis of germ cells in short-term equine testicular cultures was examined. Testicular tissue was sectioned into approximately 2-mm cubes and placed in media-filled culture chambers. Concentrations of SCF (100 ng/mL), LIF (10 ng/mL), GM-CSF (5 ng/mL), and E2 (10−9 mol/l) were added alone or in combination to each well. After 6 hours in culture, the tissue was fixed and immunohistochemically (terminal deoxynucleotidyl transferase-mediated nick-end labeling; TUNEL) stained for apoptosis detection. Apoptotic cells per 100 Sertoli cell nuclei within seminiferous tubules were counted until the 500th Sertoli cell nuclei was reached. This counting procedure was used for each slide. An analysis of variance (ANOVA) with a Tukey's test was used to compare apoptotic rates. In comparison with the control, GM-CSF alone lowered apoptosis by 34.77%. GM-CSF–treated tissue combined with SCF and LIF as well as GM-CSF combined with SCF, LIF, and E2 reduced apoptosis when compared with the control (37.45% and 44.40%, respectively) or other treatment combinations. GM-CSF alone reduced apoptosis; results suggest possible synergy for the combinations of SCF and LIF with GM-CSF and for E2 with SCF, LIF, and GM-CSF. 相似文献
112.
113.
Five fast-neutron-derived mutants were isolated from the wheat line Hobbit 'sib' that show enhanced field resistance towards Puccinia striiformis f.sp. tritici , the causal agent of yellow rust. Subsequent testing showed the yellow rust resistance phenotypes to differ between mutants, to be expressed at different growth stages and, in some cases, to show an isolate interaction. Three mutants, I3-48, I3-49 and I3-54, exhibited an enhanced yellow rust resistance phenotype from the third seedling leaf onwards, while mutants I3-27 and I3-30 did not show an altered yellow rust phenotype until later growth stages. Additional resistance for brown rust (causal agent Puccinia triticina ) was identified in mutants I3-27, I3-30, I3-48 and I3-49, and for powdery mildew caused by Blumeria graminis f.sp. tritici in mutants I3-27, I3-30, I3-48 and I3-54, although in some cases the resistance was isolate-specific. 相似文献
114.
天祝县草产业发展的制约因素及其对策 总被引:1,自引:0,他引:1
通过分析天祝县草产业发展现状,指出天祝县草产业发展存在的问题,提出要大力发展天祝县草产业必须加强天然草原综合改良,科学合理利用草原资源,建立人工草地和牧草种子繁育基地,开发草产品;建立多元化的投入机制,培植草产业开发的龙头企业;进一步完善草地管理制度,全面彻底地落实草原有偿承包责任制;建立信息网络体系,把信息网络纳入畜牧业基础设施建设范围内,建立健全草畜产品信息网络。 相似文献
115.
2006年2月18~23日位于祁连山南麓天峻县的生格乡地区,先后有20多只岩羊突然死亡。通过对捕获岩羊的临床检查、栖息地调查和对其周围牧户的访问结果表明:岩羊在短时间大量死亡是多种病原体和作为应激源气候因子(大雪、大风和强烈的太阳光直接照射和雪地反射)的联合作用导致岩羊患传染性角膜结膜炎病失明而从悬崖处摔死的结果,而人类活动导致的生境破碎化加剧了本病的发生、流行和患病动物的死亡。 相似文献
116.
A series of hybrid Flammulina velutipes dikaryons were obtained by crossing yellow and white monokaryons.The color of fruit bodies generated from these dikaryons,and the ratio between dark-colored stipe regions and the entire stipe of individual fruit bodies,were determined.Our data suggest that the expression of fruit body color in the hybrid dikaryons was under the control of factors present in both the white and yellow parent monokaryons,and that multiple alleles exist in both white and yellow color-controlling factors. 相似文献
117.
Peter A. Roussos Aristidis Matsoukis Constantine A. Pontikis Aikaterini Chronopoulou-Sereli 《Scientia Horticulturae》2007
Possible correlations among several environmental factors and the internal phenol content and oxidative enzyme activities of olive explants were examined. The statistic analysis revealed that the same environmental factor exhibited different relation with the various individual phenolic compounds found in explants and the oxidative enzyme activities. The major contribution of air temperature, total radiation, soil temperature at a depth of 25 cm and photoperiod on the explant phenol content and on the oxidative enzyme activities has been revealed. These environmental factors exhibited the highest number of significant relationships with the measured variables. 相似文献
118.
AIM: To investigate the influence of GM-CSF on human vascular endothelial cells induced to form new blood vessels and the role of VEGF. METHODS: HUVECs were cultured by Matrigel to set up a stable angiogenesis system with the stimulating factors. The rhGM-CSF concentration-dependent and time-dependent effects and the role of VEGF165 were detected. CD34 was measured by immunochemical staining and numbers of vessel formation was calculated under microscopic observation. RESULTS: After treatment with rhGM-CSF at various concentrations and at different time points, the numbers of vessel formation increased in a dose-dependent and time-dependent manner. In the presence of VEGF165, the numbers of vessel formation increased evidently. CONCLUSION: HUVECs were induced to develop tubular structure in vitro cultured with Matrigel. GM-CSF promotes human vascular endothelial cells to form vessel-like structure in vitro in a dose-dependent and time-dependent manner. VEGF also in vitro promotes human vascular endothelial cells to form new vessel-like structure. 相似文献
119.
AIM:To study the effect of VEGF on extracellular H2O2 production in HUVECs and the role of H2O2 in the VEGF-induced proliferation. METHODS:HUVECs was stimulated with 500 μg/L VEGF. Products of extracellular H2O2 was detected by H2DCFDA staining. MTT method was used to value the influences of 3×106 U/L catalase and 5-20 mmol/L H2O2 to VEGF function. RESULTS:After treatment for 15 min with VEGF, HUVECs appeared fluorescence, and continued to become stronger, peaked at 45 min then decreased. HUVECs, which was treated simultaneity with VEGF and 3×106 U/L catalase, only appeared very faint fluorescence. The proliferation of HUVECs by VEGF was restrained when treated with 3×106 U/L catalase. The extrinsic H2O2 at concentration of 5-10 mmol/L promoted the proliferation of HUVECs but inhibited the proliferation effect of VEGF on HUVECs (P<0.01). CONCLUSION:These findings indicate that VEGF induces HUVECs to produce extracellular H2O2 and plays role in proliferation, but extrinsic H2O2 restrains VEGF function. 相似文献
120.
AIM: To look for harmfulless anti-leukemia drug with selective high performance, lethal effect of small hairpin RNA (shRNA) on VEGFR2 gene expression of tumor cell line HL60 in vitro.METHODS: The most effective VEGFR2 siRNA was designed and screened. The shRNA oligo was designed and pU6/VEGFR2 entry clone was constructed. HL60 was transfected transiently and vascular endothelial growth factor receptor 2(VEGFR2) expression was tested with MTT assay, RT-PCR and Western blotting. The expression clone was constructed and cotransfected with ViraPowerTM Packaging Mix into 293FTTM cells to produce Lentiviral vectors harboring Lenti6/shVEGFR2. The virion supernatant was added into HL60 cells and VEGFR2 gene inhibitory effect was determined. RESULTS: The inhibitory rates of VEGFR2 siRNA c were high. VEGFR2 expression in HL60 was inhibited by using pU6/VEGFR2 entry clone constructed with shRNA and pENTRTM/U6. For HL60 cells, the inhibitory rate was 84.9%. The expression of VEGFR2 mRNA and protein decreased significantly. 48 hours after transfection of pU6/shVEGFR2 entry clone and transduction of Lenti6/shVEGFR2 expression clone, the cell inhibitory rates were similar. Cell growth inhibitory rate of entry clone descended rapidly after this time point, the expression clone changed slowly, reaching the peak at 96 hours, dropped slightly, having no significance deviation. CONCLUSION: in vitro, VEGFR2 shRNA using lentiviral vector blocks VEGF/VEGFR2 self-secretion in HL60 cells, which inhibits leukemia development. 相似文献