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91.
92.
摘要:为了更好地在西甜瓜特色产区北京市示范与推广优质、抗病、适合都市农业观光采摘的薄皮甜瓜新品种,带动西甜瓜品种更新换代,提高北京西甜瓜产业比较效益与竞争力,开展了彩虹5号、花宝、齐甜十里香、盛世精爽、糖金花跃5个适合北京地区观光采摘的薄皮甜瓜品种比较研究,测定了各品种植株长势、果实纵径、横径、果形指数、果肉厚度、可溶性固形物含量、外观、口感、香味以及产量等指标。结果表明:盛世精爽果肉厚度2.50 cm,中心和边缘可溶性固形物含量13.57%、10.80%,糖度梯度小,口感软糯,单瓜质量0.62 kg,折合667 m2产量为3 584.84 kg;糖金花跃次之,果肉厚度2.53 cm,中心和边缘可溶性固形物含量分别为13.67%、8.53%,具有芳香味,单瓜质量0.70 kg,折合667 m2产量为3 469.20 kg。二者综合表现较好,可作为特色观光采摘品种进行推广种植。 相似文献
93.
提高普通高校乒乓球专项课教学质量的体会与探索 总被引:1,自引:0,他引:1
根据乒乓球专项课的教学目的与任务以及多年的乒乓球训练与教学体会,提出了因材施教,分层次教学;发挥大学生智力优势促进教学;加强乒乓球基本动作和全面技术的练习与教学;加强乒乓球的教学比赛;加强乒乓球意识的培养以及加强课下练习和辅导的教学理念。使学生通过一年或两年的学习,掌握乒乓球基本技术,学会基本战术,了解乒乓球的理论知识以及比赛规则;调节身心,锻炼身体,培养学生对乒乓球运动的兴趣,为终身体育服务。 相似文献
94.
The persistence of foot-and-mouth disease virus on wool 总被引:1,自引:0,他引:1
SUMMARY Five Suffolk sheep, held in a high-security isolation room, were exposed for 2 hours to the aerosol of 3 mature pigs that had been infected with foot-and-mouth disease virus (FMDV), strain O1-BFS. The fleeces of 3 of the sheep were contaminated with FMDV at 2 days post exposure (dpe), while at 5 dpe the fleeces of all 5 sheep were more extensively, and more heavily, contaminated. The persistence of FMDV on contaminated wool was examined in vitro using multiple 0.5 g samples of Merino wool that were each contaminated with one of 3 strains of FMDV in tissue-culture medium: O1-BFS, O-Morocco (O-MOR 9/91) or an Asia 1 strain (TAI 1/90). Wool samples were held at either 4°C, 18°C or 37°C, and decay curves were established for each virus at each temperature. These curves predicted that O1-BFS, O-MOR 9/91 and TAI 1/90 would fall below detect-able levels at 72, 70 and 48 days post contamination (pc), respectively, for wool stored at 4°C; at 11, 12 and 12 days pc, respectively, for wool stored at 18°C; and at 57, 68 and 33 hours pc, respectively, for wool stored at 37°C. For wool contaminated with O1-BFS-infected sheep faeces, urine or blood, or with O1-BFS-infected cattle saliva, decay curves predicted virus to persist for 5 to 11 days pc at 18°C. We demonstrated that the simulated scouring of FMDV-contaminated wool at 60° to 70°C would usually reduce virus to below detectable levels. The detergent component of the scouring process had little, if any, antiviral activity, and scouring at 20°C or 50°C had limited impact on FMDV titres . We recommend that either (1) simple storage of FMDV-contaminated wool for 4 weeks at temperatures of 18°C or higher, or (2) scouring of contaminated wool at 60° to 70°C would be sufficient to remove the threat of FMDV-contaminated wool being infectious to other animals . 相似文献
95.
以库布齐沙漠南缘典型抛物线沙丘为研究对象,通过对沙丘土壤水分含量与紧实度的测量,分析了沙丘形态特征与土壤水分含量、紧实度的关系。结果表明,沙丘臂间平地水分含量与其周围本底值相似,高于沙丘其它地貌部位。沙丘土壤水分含量高的区域,紧实度较大,抗侵蚀能力较强。沙丘土壤水分含量、紧实度等物理性状特征也影响植被的发育与分布。 相似文献
96.
97.
综述了卵泡生长发育的动态模式,即卵泡经原始卵泡、初级卵泡、次级卵泡和窦腔卵泡发育至排卵卵泡的过程,着重阐述了卵泡生长发育过程中的调控机制,为进一步研究卵泡的生长、发育和排卵机制提供了理论基础。 相似文献
98.
JIA Ya-nan LI Ru-jia WANG Ke-ke LEI Hong HA Yan-ping Wang Si-si LIAO Xiao-min JIE Wei SHEN Zhi-hua 《园艺学报》2017,33(8):1386-1392
AIM: To explore the expression and significance of receptor tyrosine kinase anexelekto (Axl) in nasopharyngeal carcinoma (NPC). METHODS: Immunohistochemistry was used to detect the Axl protein expression of 78 patients with NPC and 32 patients with nasopharyngeal chronic inflammation (NPI). The correlations between the Axl protein levels and the clinical parameters of NPC patients were analyzed. NPC cells were cultured in vitro, and the expression of Axl in well differentiated CNE1 cells, poorly-differentiated CNE2Z cells and undifferentiated C666-1 cells was detected by immunofluorescence staining. After treatment of the CNE1and C666-1 cells with Axl specific inhibitor TP-0903, CCK-8 assay was used to detect cell viability, flow cytometry was adopted to analyze the cell cycle distribution, qPCR was used to examine the mRNA levels of Axl and proliferating cell nuclear antigen (PCNA), and Western blot was used to examine the protein expression of Axl and p-Axl. RESULTS: Axl protein was localized in the cell membrane and cytoplasm. The rate of high expression of Axl in NPC was significantly higher than that in NPI (P<0.01). High Axl expression showed no correlations with NPC patients' age, gender and M stage, while positively correlated with the clinical stage, T stage and N stage (P<0.05). Axl protein showed a low level in the CNE1 cells, but showed a high level in CNE2Z and C666-1 cells. TP-0903 inhibited cell viability in concentration and time dependent manners. TP-0903 at 2 nmol/L showed significant inhibitory effects, as evidenced by arresting the cell cycle at G0 phase and reducing Axl activity and PCNA expression. CONCLUSION: High expression of Axl promotes the clinical progress of NPC.TP-0903 significantly inhibits the viability of NPC cells, suggesting that Axl may be a valuable target in the NPC treatment. 相似文献
99.
为建立特异、敏感、快速的二温式PCR诊断方法,根据牛环形泰勒虫裂殖子表面抗原(tams1)基因,设计了一对特异性引物,扩增出大小为154bp基因片段,经克隆、测序分析,与已知基因序列的相似性为96%。用建立的牛环形泰勒虫病二温式PCR诊断方法,对从新疆牛环形泰勒虫病流行地区采集的50份全血样品进行诊断,阳性率为88%,而血涂片检出的阳性率只有58%。经试验验证,该方法具有特异性高、敏感性强、重复性和稳定性好等优点。表明本试验所建立的二温式PCR诊断方法可用于牛环形泰勒虫病的临床诊断、隐性感染检测和流行病学调查。 相似文献
100.