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151.
妊娠和激素干预对豚鼠卵巢囊淋巴孔的影响 总被引:3,自引:0,他引:3
In order to study the influence of pregnancy and hormone on the lymphatic stomata of guinea pig's ovary bursa, the lymphatic stomata of ovary bursa were observed during pregnancy and by using exogenous hormone, including serum gonadotrophin (PMSG) combined with human chorionic gonadotropin (HCG) to promote ovulation and androgen to inhibit the ovary. Then the lymphatic stomata in the inner layer of ovary bursa and their absorption functions were observed with scanning electron microscope (SEM) and trypan blue as a tracer respectively. The lymphatic stomata were also counted by the Elescope computer image processing system. We found that the quantity of tracer absorbed by the lymphatic stomata of ovary bursa in pregnant group was more than that in ovulation-promoted group, and least in the androgen-treated group, which had statistical significance between each couples of them (P < 0.05). The opening area of the lymphatic stomata in pregnant, ovulation-promoted and androgen-treated groups were 189.9 +/- 48.7 micron 2/1000 micron 2, 104.4 +/- 31.2 micron 2/1000 micron 2 and 40.5 +/- 18.7 micron 2/1000 micron 2 respectively, which had remarkable statistical difference between each couples (P < 0.01). Under SEM observation, the secretory granules in ciliated columnar epithelium were less in pregnant group than the other two, while both the secretory granules and the cilium were most active in ovulation-promoted group. The results indicated that both the openings and absorption functions of the lymphatic stomata in guinea pig's ovary bursa could be affected by pregnancy and exogenous homone. There existed relationship between ovary function and the regulation of the lymphatic stomata in ovary bursa. 相似文献
152.
大鼠急性呼吸窘迫综合征动物模型的建立 总被引:9,自引:1,他引:8
目的 建立大鼠急性呼吸窘迫综合征动物模型 (ARDS)。方法 选取KM小鼠SD大鼠 (雌雄不限 ) ,分为正常对照组及百草枯组 ,小鼠按每公斤体重 10 0mg ,大鼠按每公斤体重 12 0mg一次灌胃给药。再分 2 4h、4 8h、72h组 ,小鼠每组 10只股动脉采血用于血气分析 ,取肺测定肺系数 ,全肺拍照进行对照 ,大鼠每组 10只取肺石腊包埋 ,病理切片。结果 ①整体外观变化 随着给药时间延长 ,呼吸变得越来越困难、消瘦、咳嗽 ,2 4h后鼻腔有淡红色分泌物 ,食欲渐进性下降。②肺外观观察炎症渐进性发展 ,从正常粉红色发展到最后呈肝样变。③血气变化 随染毒时间延长 ,血液pH值逐渐降低 ,PaCO2 逐渐升高 ,PaO2 逐渐下降 ,肺系数逐渐增大 ,组间数据进行t检验p <0 0 1,差异有显著性。④病理切片观察肺部呈典型炎症病理变化过程 ,最终肺泡内形成典型透明膜。结论 百草枯染毒成功制造鼠ARDS模型。 相似文献
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神经系统中的IgSF蛋白是一类重要的神经细胞表面分子,种类繁多,功能多样,其中一类分子缺乏跨膜区,通过GPI锚结合在细胞膜上,表现出结构和功能的特异性。本文对该类神经元GPI锚定蛋白分子作一系统介绍。根据结构特点,神经元GPI锚定蛋白分子可分为三类,各类分子通过Ig结构域与其自身或其它蛋白分子进行顺式或反式结合,调节神经细胞活动。 相似文献
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Shaohui Wang Liping Hu Jianlei Sun Xiaolei Sui Yuxia Wei Zhenxian Zhang 《Plant Growth Regulation》2012,66(1):87-93
Cucumber (Cucumis sativus L.) seeds were pretreated with exogenous abscisic acid (ABA) prior to germination. After germination, seedlings with three
leaves were exposed to gradual dehydration. The effects of ABA on photosynthetic rate (Pn), daily water loss (WL) and water
utilization efficiency (WUE) during dehydration were investigated, in addition to the variation of carbohydrates in leaves.
ABA improved the Pn, WL and WUE of cucumber seedlings during dehydration. After rehydration, the seedlings pretreated with
ABA showed a higher recovery in Pn, WL and WUE, as compared to those without an ABA pretreatment. Subsequent to dehydration,
concentration of stachyose, raffinose, sucrose, glucose, and fructose increased in seedlings pretreated with ABA. Dehydration
altered the proportions of the sugars in the total carbohydrates, and accelerated the accumulation of stachyose, raffinose
and sucrose. After rehydration, carbohydrate concentrations of seedlings pretreated with ABA recovered to levels observed
prior to dehydration. These results demonstrated that pretreatment of seeds with exogenous ABA enhanced carbohydrate tolerance
to dehydration of cucumber seedlings. 相似文献