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31.
为了研究新城疫病毒(NDV)和宿主细胞之间的相互作用关系,本研究以NDV感染鸡胚成纤维细胞(CEF)为材料,对细胞培养方式、样品制备方法、上样量、等电聚焦以及凝胶染色等步骤进行一系列优化,建立了NDV感染CEF的双向凝胶电泳技术。运用PDQuest8.0.1软件对电泳图谱分析后显示:17cmIPG胶条(pH4~7)对应的凝胶上可检测到800个左右蛋白点、蛋白点匹配率达90%,表明NDV感染CEF蛋白质组双向凝胶电泳模型稳定、分辨率高、重复性好。电泳图谱上共发现36个差异表达明显的蛋白点,其中上调表达蛋白点有16个,下调表达蛋白点15个,新出现蛋白点3个,消失蛋白点为2个。NDV感染CEF双向凝胶电泳技术的建立为NDV的致病机理研究提供了有力的工具。  相似文献   
32.
小流域治理中的水土保持型观光农业   总被引:2,自引:0,他引:2  
观光农业是农业与观光业相结合的一种复合型产业,其设计要求经济发展与环境保护相协调、资源利用和资源保护相统一。泰安市背靠泰山,旅游资源得天独厚,小流域治理中的水土保持型观光旅游农业应围绕泰山大旅游做文章。详细介绍了国内外观光农业的发展概况,并以泰安市小流域观光旅游农业的发展为例,介绍了观光农业的几种成功模式。  相似文献   
33.
采用生态足迹模型对连云港市的生态承载力和生态足迹进行了研究。结果表明,1997~2006年连云港市处于严重的生态赤字状态,人均生态承载力呈减小趋势,生态系统的不稳定性日渐增强。  相似文献   
34.
为进一步增强江苏省兽医系统实验室对动物疫病的监测预警能力,本文对江苏疫控中心2021年10月组织的全省兽医系统(12个市级、65个县级)实验室比对结果进行了统计,样品正确率为97.81%(1115/1140),实验室正确率为84.42%(65/77)。比对结果表明,77个实验室均具备开展主要动物疫病监测预警的技术能力,但少数实验室的个别比对项目检测结果存在一定偏差。提示仍然需要加强实验室建设,包括扩充专业人才队伍、增加资金投入、及时更新检测设备等,不断提高检测业务能力。  相似文献   
35.
普通白菜〔Brassica campestris L.ssp.chinensis(L.)Makino var.communis Tsen et Lee〕属十字花科芸薹属,是我国长江流域及南方各省普遍栽培的重要绿叶蔬菜之一,生产中迫切需要培育抗病、抗虫、抗逆和具有优良农艺性状的新品种。遗传转化技术为普通白菜抗虫、抗病、耐热等难题提供了新的解决途径。本文对普通白菜的再生体系、遗传转化方法及外源基因表达等研究进展进行了概述;农杆菌介导法由于成本低、简便易行、转化效率较高,成为白菜类作物遗传转化中最常用的办法。  相似文献   
36.
Acetylcholinesterase (AChE) histochemistry and quantitative analysis were used to investigate and compare the projections and densities of cerebral perivascular AChE nerves in five avian species. In the society finch, AChE nerves arising from the cerebral carotid, internal ethmoidal and vertebral arteries generally have no overlap with each other. This is different from AChE neuronal projections via these three vascular routes reported previously for the pigeon, duck, chicken and quail. AChE nerves supplying the pigeon cerebral arterial tree are the highest in density, predominate in the anterior circulation (AC) rather than in the posterior circulation (PC). Similar differential supply of nerves is also found in the duck, with a marked low density in the PC. In contrast, the chicken PC has a substantial amount of AChE nerves that is larger than the fiber amount contained in the AC. The reduction of nerves is far greater in both the AC and PC of the finch. It is not so prominent as that seen in the quail. The significant difference in the distribution and density of cerebral perivascular AChE nerves presented here may indicate that there are some species-specific cholinergic controlling mechanisms responsible for the cerebral circulation of birds.  相似文献   
37.
暖季限时放牧对草地植被的影响   总被引:1,自引:0,他引:1  
通过对三种不同时间的限时放牧与自由放牧条件下的草地植被群落特征、群落多样性及产草量之间比较研究表明:与自由放牧相比,限时放牧对草地植被有明显的影响,其中5h限时放牧区的草地植被高度、盖度、多度、多样性指数、均匀度指数、丰富度指数及产草量均高于6h限时放牧区、7h限时放牧区和自由放牧区.  相似文献   
38.
Multiple whitish nodules in the thoracic cavity at the site of the thymus were observed in a 101-week-old male ICR mouse. In a histopathological examination, the neoplastic cells were predominantly fusiform in shape and proliferated in sarcomatoid growth patterns. Some neoplastic cells showed epithelial growth patterns, such as the ductal structures. Mitotic figures were frequently seen, and small necrotic foci and invasion to adjacent thoracic organs were noted. In Alcian blue staining, bluish materials were observed between fusiform-shaped cells and in some of the lumens of the ductal structures. In immunohistochemistry, both fusiform-shaped and ductal structure-forming cells were positive for vimentin and weakly positive to positive for cytokeratin. Based on the aforementioned findings, the thoracic nodules were diagnosed as a mixed type of malignant mesothelioma. This case was thought to be rare because of the very low occurrence of spontaneous mesothelioma in mice.  相似文献   
39.
We determined the sequence of the immunoglobulin gamma heavy‐chain constant (IGHC) region of the Mongolian gerbil (Meriones unguiculatus). To isolate a part of the IGHC complementary DNA, we designed primers on the basis of highly conserved sequences in mouse, rat and hamster. The deduced IGHC is structurally similar to counterparts in other mammalian species and shows 84.6% identity to the IGHC of hamster IgG, 76.6% to rat IgG1, 83.3% to rat IgG2a, 78.1% to mouse IgG1, 81.8% to mouse IgG2a, 79.1% to mouse IgG2b and 79.2% to mouse IgG3 at the nucleotide level. The results suggest that gerbil IgG is closely related to hamster IgG and rat IgG2a.  相似文献   
40.
Bilateral ovariectomy (Ovx) was carried out on day 20 of pregnancy in Mongolian gerbils ( Meriones unguiculatus ). The body weights of all groups tended to decrease on the day after the operation, and the decrease was significant in the group that was ovariectomized and given vehicle (Ovx + vehicle group). The body weight in this group never recovered until autopsy on day 24, which is normally 1 day before parturition. No fetuses survived to the time of autopsy in any of the animals of the Ovx + vehicle group. Daily administration of 4 mg of progesterone (P4) prevented the termination of pregnancy in Ovx animals, but 1 mg did not. Treatment with estradiol 17β (E2) in addition to 4 mg of P4 tended to result in a lower rate of fetal survival than that of the Ovx group treated with 4 mg of P4 alone. With regard to fetal weight, treatment with 4 mg of P4 resulted in the same weight as in the sham-operated controls, but the addition of 0.2 or 1 μg of E2 to the 4 mg of P4 resulted in a significantly lower weight than that of fetuses in the 4 mg of P4 group. The present study suggests that adequate maintenance of pregnancy in ovariectomized gerbils can be achieved by daily treatment with 4 mg of P4 alone. Moreover, treatment with 0.2 or 1 μg of E2 in addition to 4 mg of P4 caused a deterioration in the maintenance of gestation, in contrast to the effects in rats, mice and hamsters.  相似文献   
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