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951.
目的:通过建立了内质网应激预处理条件下的大鼠肝脏缺血再灌注损伤模型,探讨内质网应激预处理在体内的应用.方法:以衣霉素为内质网应激诱导剂,采用大鼠肝脏70%缺血再灌注损伤模型.按照不同给药剂量分为50μ g/kg组、100μ g,kg组、200μ g/kg组、对照组,观察不同给药剂量条件下,血清转氨酶水平的变化.结果:给药100μ g/kg体重、诱导5天条件下大鼠术后转氨酶水平显著低于对照组.其它组与对照组无统计学差异.肝组织病理切片证实该预处理条件对肝脏缺血再灌注损伤有显著保护作用.结论:在特定的给药剂量条件下,衣霉素诱导的内质网应激预处理对大鼠肝脏缺血再灌注损伤有显著的保护作用. 相似文献
952.
Guo-cheng Fan Fang-luan Gao Tai-yun Wei Mei-ying Huang Li-yan Xie Zu-jian Wu Qi-ying Lin Lian-hui Xie 《中国病毒学》2010,25(6):401-408
To obtain the P8 protein of Rice gall dwarf virus (RGDV) with biological activity, its outer coat protein gene S8 was expressed in Spodoptera frugiperda (Sf9) insect cells using the baculovirus expression system. The S8 gene was subcloned into the pFastBac™1 vector, to produce the recombinant baculovirus transfer vector pFB-S8. After transformation,
pFB-S8 was introduced into the competent cells (E. coli DH10Bac) containing a shuttle vector, Bacmid, generating the recombinant bacmid rbpFB-S8. After being infected by recombinant
baculovirus rvpFB-S8 at different multiplicities of infection, Sf9 cells were collected at different times and analyzed by
SDS-PAGE, Western blotting and immunofluorescence microscopy. The expression level of the P8 protein was highest between 48–72
h after transfection of Sf9 cells. Immunofluorescence microscopy showed that P8 protein of RGDV formed punctate structures
in the cytoplasm of Sf9 cells. 相似文献
953.
Developments of stem cell biology provide new approaches for understanding the mechanisms of a number of diseases, including
osteoporosis. In this minireview, we highlight two areas that related to stem cells in bone biology. Recent discovery of the
role of osteoclast and their stem cells leads to developing a new approach for treatment of osteoporosis with the initial
stimulation of cells in osteoclast lineage and followed by sequentially enhanced bone formation. Stimulation on both sides
in bone remodeling is expected to achieve a long term effect on bone formation. For bone regeneration, multiple disciplinary
collaborations among bone biologists, stem cell biologists and biomaterial scientists are necessary to successfully develop
an integrated stem cell therapy that should include stem cells, suitable scaffolds and bioactive factors/small molecular compounds. 相似文献
954.
Spatially complex neighboring relationships among grassland plant species as an effective mechanism of defense against herbivory 总被引:2,自引:0,他引:2
Ling Wang Deli Wang Yuguang Bai Yue Huang Meng Fan Jushan Liu Yexing Li 《Oecologia》2010,164(1):193-200
Close spatial relationships between plant species are often important for defense against herbivory. The associational plant
defense may have important implications for plant community structure, species diversity, and species coexistence. An increasing
number of studies have focused on associational plant defense against herbivory at the scale of the individual plant and its
nearest neighbors. However, the average neighborhood effects between plant species at the scale of whole plant communities
have received almost no attention. The aims of this study were to determine patterns of spatial relationship between different
plant species that can provide effective defense against herbivory. We conducted a manipulative experiment using sheep and
three native plant species with different palatability. Consumption of palatable plants by herbivores was largest when the
three plant species were isolated in three patches and independent of each other. A homogenous and spatially equal neighbor
relationship between the three species did not reduce the risk of herbivory of palatable species compared to isolation of
these species, but it reduced the total intake of all plant species. The palatable species was subject to less herbivory in
a complex spatial neighborhood of several plant species. High complexity of spatial neighborhood resulted in herbivores passively
reducing selectivity, thereby reducing the probability of damage to palatable species in the community, or making inaccurate
judgments in foraging selectivity between and within patches, thereby reducing the vulnerability of palatable plants and even
the whole plant community. We conclude that compelling herbivores to passively reduce the magnitude of foraging selectivity
by establishing spatially complex neighborhoods between plant species is a compromise and optimal spatial strategy by plants
to defend themselves again herbivory. This may contribute not only to maintenance of plant species diversity but also to a
stable coexistence between herbivores and plants in grassland ecosystems. 相似文献
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Background
In insects, hemocyanin superfamily proteins accumulate apparently to serve as sources of amino acids during metamorphosis, reproduction and development. Storage hexamerins are important members of the hemocyanin superfamily. Although insects possess storage hexamerins, very little is known about the character and specific functions of hexamerin 1 and storage protein 1 in insect development. 相似文献959.
Mingjun Zhang Scott C Lenaghan Lijin Xia Lixin Dong Wei He William R Henson Xudong Fan 《Journal of nanobiotechnology》2010,8(1):20
Background
The search for naturally occurring nanocomposites with diverse properties for tissue engineering has been a major interest for biomaterial research. In this study, we investigated a nanofiber and nanoparticle based nanocomposite secreted from an insect-capturing plant, the Sundew, for cell attachment. The adhesive nanocomposite has demonstrated high biocompatibility and is ready to be used with minimal preparation. 相似文献960.
Sebastian Dolff Daniel Quandt Benjamin Wilde Thorsten Feldkamp Fan Hua Xin Cai Christof Specker Andreas Kribben Cees GM Kallenberg Oliver Witzke 《Arthritis research & therapy》2010,12(4):R150