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91.
The motility outcomes of boar semen frozen with newly developed freezing techniques using a new unique freezing technology (UFT) compared with traditional liquid nitrogen methodology were investigated with the intent of improving current fertility outcomes using semen. The UFT is an electronically controlled cooling chamber that houses an organic fluid bath that can be maintained at temperatures below 0 degrees C without solidifying to freeze samples. Four ejaculates from four different boars were collected for this trial. Samples were handled consistently during the pre- and post-freeze processing. From each ejaculate, samples were separated into eight cryopreservation treatment groups, six UFT variations and two control liquid nitrogen groups, immediately before freezing, in replicates of two. After the initial cryopreservation was complete, all samples were stored in liquid nitrogen for at least 48 h. Post-thaw motilities and original motility return percentages were assessed on a random, individual-sample basis. After the initial evaluations, samples from two boars were recollected and frozen using the UFT for breeding purposes. Four sows were bred with the UFT frozen semen to confirm fertility capability. When assessing the individual UFT techniques, all of six UFT techniques had improved post-thaw motilities. However, treatments F (micro = 29%, return micro = 37%) and J (micro = 27%, return micro = 34%) showed the highest statistical improvement for post-thaw (p < 0.05) and original motility percent returns (p < 0.05) when compared with either the control cryo-tube (micro = 15%, return micro = 19%) or straw groups (micro = 12%, return micro = 16%). The UFT semen had a 50% conception rate, with an average of seven piglets from the sows that farrowed. Our preliminary data suggest a higher motility return with a slower pre-freeze phase below the freezing point before the acceleration to liquid nitrogen temperatures. The preliminary data suggest that the UFT could be utilized as a potential cryopreservation option for boar semen. 相似文献
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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
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鸡公山自然保护区森林植被生物量及活碳蓄积量研究 总被引:3,自引:0,他引:3
运用鸡公山科学考察资料及1999年森林资源清查资料,采用森林材积源生物量推算方法研究了鸡公山森林植被生物量及其活碳蓄积量。结果表明:鸡公山森林植被生物量总值为309 202t,平均森林植被生物量为111.7t/hm2,高于全国平均水平(77.4t/hm2);鸡公山森林植被的总活碳蓄积量为154 601t,平均活碳密度为56MgC/hm2,高于中国森林植被活碳密度的平均水平(38.7 MgC/hm2),但低于全球平均碳密度(86MgC/hm2)。不同林型活碳蓄积密度分析结果表明,马尾松、杉木和栎类林木的活碳蓄积密度分别为30MgC/hm2,39 MgC/hm2和70MgC/hm2,均高于全国同类型森林植物的活碳蓄积密度的平均值,而次生阔叶混交林的碳蓄积密度略低于全国平均水平。鸡公山自然保护区67%的森林为中龄林,27%的森林为幼龄林,在增加碳蓄积方面还有巨大的潜力。 相似文献
96.
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
97.
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
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99.
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