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101.
选用5只年龄为3~4岁的波尔山羊公羊研究在稀释液中添加海藻糖对山羊精子功能和膜完整性的影响。山羊精子分别用含6.6 mmol/L、13.2 mmol/L、19.8 mmol/L、26.4 mmol/L、39.6 mmol/L、52.9 mmol/L、66.1mmol/L、79.3 mmol/L的不同海藻糖的Tris-柠檬酸-葡糖糖(TCG)稀释液(卵黄:18%;甘油:6%)稀释和冷冻。结果表明:39.6 mmol/L、52.9 mmol/L、66.1 mmol/L、79.3 mmol/L组降温后的精子活率显著(P<0.05)降低;52.9 mmol/L、66.1 mmol/L、79.3 mmol/L组降温后的精子畸形率和39.6 mmol/L组降温后的膨胀精子率显著(P<0.05)提高。26.4 mmol/L组和39.6 mmol/L组冻融后的精子活率显著(P<0.05)高于对照组;66.1mmol/L和79.3 mmol/L组冻融后的精子活率、畸形率分别显著(P<0.05)低于和高于对照组。19.8 mmol/L、26.4 mmol/L、39.6 mmol/L组冻融后精子获能率显著(P<0.05)低于对照组。39.6 mmol/L组冻融后顶体完整率和膨胀精子率显著(P<0.05)高于对照组,而66.1 mmol/L组和79.3 mmol/L组显著(P<0.05)低于对照组。39.6 mmol/L组的受胎率显著(P<0.05)高于对照组,而66.1mmol/L组和79.3 mmol/L组的受胎率显著(P<0.05)低于对照组。结果表明,在含18%的卵黄(v/v)、6%甘油(v/v)的TCG稀释液中,添加适宜浓度(26.4mmol/L和39.6 mmol/L)海藻糖,可显著提高山羊精子功能和膜的完整性。  相似文献   
102.
【目的】本研究旨在通过饲喂法对意大利蜜蜂Apis mellifera ligustica工蜂幼虫肠道中ame-miR-bantam进行过表达与敲减,明确ame-miR-bantam对靶基因USP和P300表达的调控作用。【方法】通过饲喂ame-miR-bantam模拟物(mimic-ame-miR-bantam)和抑制物(inhibitor-ame-miR-bantam)及相应的阴性对照mimic-NC-ame-miR-bantam和inhibitor-NC-ame-miR-bantam,对意大利蜜蜂工蜂4-6日龄幼虫肠道组织中的ame-miR-bantam分别进行过表达和敲减。利用生物信息学软件进行ame-miR-bantam的靶向预测及分析。通过RT-qPCR检测4-6日龄意大利蜜蜂工蜂幼虫肠道中ame-miR-bantam的过表达和敲减效果及靶基因USP和P300的相对表达量。【结果】相较于饲喂mimic-NC-ame-miR-bantam,饲喂mimic-ame-miR-bantam后,ame-miR-bantam在意大利蜜蜂4-6日龄工蜂幼虫肠道中均显著上调;相较于饲喂inh...  相似文献   
103.
Background: Endometriosis (EMS), a typical endocrine immune disorder, associates with dramatically increased estrogen production and disorganized immune response in ectopic focus. Peritoneal regulatory T cells (Tregs) expansion in women with EMS and their pathogenic role attributable to endometriotic immunotolerance has been reported. Whether local high estrogen promotes EMS by discipling Tregs needs to be further explored. Up to date, there is no effective medicine for the treatment of EMS. SCM-198 is a synthetic leonurine with multiple physiological activities. Whether SCM-198 could regulate Tregs via estrogen and facilitate the radical cure of EMS has not yet been reported.Methods: Proportion of Tregs in peritoneal fluid of patients with EMS was firstly analyzed via flow cytometry. Peritoneal estrogen concentration and the mRNA levels of estrogen receptor α (ERα) and estrogen receptor β (ERβ) of Tregs were detected by ELISA and RT-PCR, respectively. Grouped in vitro induction assays were performed to explore the effects of SCM-198 and estrogen signaling on Tregs. Cell invasion and viability assays were utilized to detect the crosstalk between Tregs and ectopic endometrial stromal cells (eESCs), with or without SCM-198 treatment. Furthermore, EMS mice models were established to verify the therapeutic effects of SCM-198.Results: Increased Tregs were found in peritoneal fluid of EMS patients, accompanied with estrogen-ERα overactivation. Estrogen-ERα triggered the expansion of Tregs and their cytokine production (IL-10 and TGF-β1), which could be reversed by SCM-198 treatment. Moreover, SCM-198 abated the invasion and viability of eESCs enhanced by Tregs. In vivo experiments confirmed that SCM-198 obviously retarded the growth of ectopic lesions and downregulated the functions of Tregs via estrogen-ERα inactivation.Conclusions: These data suggest that SCM-198 attenuates Tregs expansion via the inhibition of estrogen-ERα signaling in EMS and offer a promising therapy for such a refractory disease.  相似文献   
104.
陈小麟 《动物学研究》1999,20(5):336-341
以干旱地区的肉食性步甲科(Carabidae)和植食性拟步甲科(Tenebrionidae)昆虫成体为材料,测定鞘翅目甲虫的含能值和含水量,分析其含能值和含水量的相互关系及其变动规律.结果表明,肉食性步甲科昆虫的含能值(22.64 J/mg无灰干重)显著高于植食性拟步甲科昆虫(20.55 J/mg无灰干重)(P<0.05),相反,前者的含水量(54.96%)却显著地低于后者(63.28%)(P<0.05).步甲科和拟步甲科昆虫的含能值都与其含水量成显著负相关(r=-0.5962,P<0.05).步甲科和拟步甲科昆虫的含能值或含水量具有明显的季节变动规律,两科的变动规律基本相同,其中,含能值在秋季最高(22.80 J/mg无灰干重),春季最低(20.42 J/mg无灰干重),含水量则相反,秋季最低(54.93%),春季最高(61.88%)(P<0.05).步甲科和拟步甲科昆虫的头、胸、腹和附肢不同体区的含能值具有显著差异(P<0.05),其中,腹部的含能值最高(22.65 J/mg无灰干重),其次为胸部(21.33 J/mg无灰干重),头部和附肢的含能值最低(20.89 J/mg无灰干重和20.60 J/mg无灰干重).不同体区的含能值也具有同样的季节变动,即含能值在秋季最高(22.30 J/mg无灰干重),春季最低(19.46 J/mg无灰干重)(P<0.05).步甲科和拟步甲科昆虫的个体含能值与其头、胸、腹和附肢各体区的含能值成正相关,相关系数分别为0.718、0.846、0.897和0.604(P<0.05);其中个体含能值与腹部或胸部体区含能值的相关系数显著地高于它们与头部和附肢含能值的相关系数(P<0.05);这些结果说明,脂质在甲虫腹部和胸部的积聚是引起甲虫个体含能值提高的主要原因.本文对不同食性甲虫含能值产生差异的原因,甲虫含能值和含水量变动的影响因素也进行了分析;并结合最佳摄食理论,就甲虫作为猎物,其含能值和含水量的这些变动规律对食虫动物食物选择所可能产生的影响也进行了探讨,就今后进一步检验食虫动物摄食对策所应开展的猎物喂养食虫动物的实验提出建议.  相似文献   
105.
任炳忠  赵卓  郝锡联 《昆虫学报》2002,45(Z1):20-21
 记述了采自松嫩草原的雏蝗属Chorthippus Fieber一新种, 即吉林雏蝗Chorthippus jilinensis sp. Nov.,并与其近似种翠饰雏蝗C.dichrous (Ev.)做了比较。模式标本保存于东北师范大学生命科学学院动物标本室。  相似文献   
106.
洋葱"昌激99-3"的激光诱变选育   总被引:5,自引:0,他引:5  
采用CO2和He-Ne两种激光的三种剂量,分别辐照两个洋葱品种的湿种子,从He-Ne和CO2激光辐照元谋洋葱变异后代中选育出高产、优质、多抗、适应性较强的红皮洋新品种“昌激99-3”,经专家组实地验收亩产达9186.7Kg,是红皮洋葱经专家正式验收的全国最高产量。  相似文献   
107.
Toxoplasma gondii is a persistent protozoan parasite capable of infecting almost any warm-blooded vertebrate. The surface of Toxoplasma is coated with a family of developmentally regulated glycosylphosphatidylinositol (GPI)-linked proteins (SRSs), of which SAG1 is the prototypic member. SRS proteins mediate attachment to host cells and interface with the host immune response to regulate the virulence of the parasite. The 1.7 A structure of the immunodominant SAG1 antigen reveals a homodimeric configuration in which the dimeric interface is mediated by an extended beta-sheet that forms a deep groove lined with positively charged amino acids. This basic groove seems to be conserved among SRS proteins and potentially serves as a sulfated proteoglycan-binding site on target cell surfaces, thus rationalizing the promiscuous attachment properties of Toxoplasma to a broad range of host cell types.  相似文献   
108.
采用不同浓度的抗坏血酸(50—800μmol/L)和硫酸亚铁(2.5—40μmol/L)系统生成以羟自由基为主的各种程度氧胁迫,使之作用于人肝癌细胞。本文所采用的不同程度的氧胁迫均能抑制癌细胞的生长。低水平氧胁迫可使肝癌细胞失去某些恶性特征,趋向分化,表现为细胞表面对Con-A的凝集力、甲胎蛋白含量、γ-谷氨酰转肽酶和酪氨酸-α-酮戊二酸转氨基酶活性都朝着分化方向变化,差异显著。分化后的细胞克隆形成能力显著降低。在分化过程中,出现一定量的凋亡细胞。随着氧胁迫程度的增高,凋亡细胞增多,表现为非贴壁细胞增多,细胞体积变小,染色质凝缩在核膜边缘,呈新月形,核碎裂,但质膜完整。细胞核中DNA降解成大约21.2kbp大小的大片段DNA。有望通过严格控制氧胁迫程度来减慢肝癌细胞增殖,促进分化和凋亡,使恶性细胞逆转成良性细胞。  相似文献   
109.
110.
Net ecosystem productivity (NEP) was continuously measured using the eddy covariance (EC) technique from 2003 to 2005 at three forest sites of ChinaFLUX. The forests include Changbaishan temperate mixed forest (CBS), Qianyanzhou subtropical coniferous plantation (QYZ), and Dinghushan subtropical evergreen broad‐leaved forest (DHS). They span wide ranges of temperature and precipitation and are influenced by the eastern Asian monsoon climate to varying extent. In this study, we estimated ecosystem respiration (RE) and gross ecosystem productivity (GEP). Comparison of ecosystem carbon exchange among the three forests shows that RE was mainly determined by temperature, with the forest at CBS exhibiting the highest temperature sensitivity among the three ecosystems. The RE was highly dependent on GEP across the three forests, and the ratio of RE to GEP decreased along the North–South Transect of Eastern China (NSTEC) (i.e. from the CBS to the DHS), with an average of 0.77 ± 0.06. Daily GEP was mainly influenced by temperature at CBS, whereas photosynthetic photon flux density was the dominant factor affecting the daily GEP at both QYZ and DHS. Temperature mainly determined the pattern of the interannual variations of ecosystem carbon exchange at CBS. However, water availability primarily controlled the interannual variations of ecosystem carbon exchange at QYZ. At DHS, NEP attained the highest values at the beginning of the dry seasons (autumn) rather than the rainy seasons (summer), probably because insufficient radiation and frequent fog during the rainy seasons hindered canopy photosynthesis. All the three forest ecosystems acted as a carbon sink from 2003 to 2005. The annual average values of NEP at CBS, QYZ, and DHS were 259 ± 19, 354 ± 34, and 434 ± 66 g C m−2 yr−1, respectively. The slope of NEP that decreased with increasing latitude along the NSTEC was markedly different from that observed on the forest transect in the European continent. Long‐term flux measurements over more forest ecosystems along the NSTEC will further help verify such a difference between the European forest transect and the NSTEC and provide insights into the responses of ecosystem carbon exchange to climate change in China.  相似文献   
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