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131.
132.
为了解暗腹雪鸡(Tetraogallus himalayensis)正常血液生理生化特性,本文对暗腹雪鸡21项血液生理生化指标进行了测定,并与海兰褐鸡(Gallus gallus domesticus var. Hyline)进行了比较。测定结果,暗腹雪鸡的红细胞纵径及横纵径乘积、平均红细胞容积及平均红细胞血红蛋白含量极显著大于海兰褐鸡(P<0.01);暗腹雪鸡天冬氨酸氨基转移酶和胆固醇含量均极显著高于海兰褐鸡(P<0.01)。其他各项血液生理生化指标两禽种间之间差异不显著。实验结果表明,暗腹雪鸡血液生理生化指标与家养蛋鸡之间有一定差异,暗腹雪鸡对高原低氧环境有较强的适应性可能与其红细胞体积较大、平均红细胞容积及平均红细胞血红蛋白含量较高有一定关系。 相似文献
133.
Wenjuan Bi Zhiyuan Gu Yuanna Zheng Limin Wang Jing Guo Gang Wu 《Development, growth & differentiation》2013,55(9):744-754
The osteogenesis of bone marrow stromal cells (BMSCs) is of paramount importance for the repair of large‐size bone defects, which may be compromised by the dietary‐accumulated all‐trans retinoic acid (ATRA). We have shown that heterodimeric bone morphogenetic protein 2/7 (BMP2/7) could induce bone regeneration in a significantly higher dose‐efficiency in comparison with homodimeric BMPs. In this study, we evaluated the effects of ATRA and BMP2/7 on the proliferation, differentiation, mineralization and osteogenic genes. ATRA and BMP2/7 exhibited both antagonistic and synergistic effects on the osteogenesis of BMSCs. ATRA significantly inhibited proliferation and expression of osteocalcin but enhanced the activity of alkaline phosphatase of BMSCs. On day 21, 50 ng/mL BMP2/7 could antagonize the inhibitive effects of ATRA and significantly enhance osteogenesis of BMSCs. These findings suggested a promising application potential of heterodimeric BMP2/7 in clinic to promote bone regeneration for the cases with dietary accumulated ATRA. 相似文献
134.
Cui-rong Zhao Rui-qi Wang Gang Li Xiao-xia Xue Chang-jun Sun Xian-jun Qu Wen-bao Li 《Bioorganic & medicinal chemistry letters》2013,23(7):1989-1992
New series of indazole based diarylureas were synthesized and their anticancer activity against cancer cells H460, A549, OS-RC-2, HT-29, Lovo, HepG2, Bel-7402, SGC-7901 and MDA-MB-231 were examined. These derivatives of diarylureas, except azaindazole based diarylureas 5f, 5l and 5m, showed superior or similar activity against most of these selected cancer cell lines to the reference compound sorafenib. The effect of substituents on the indazole ring was also investigated. Derivatives with trifluoromenthy or halogen substituent on the indazole ring showed higher activity against the selected cancer cell lines than sorafenib. The acute toxicity assay showed that compounds 5a, 5b and 5i possessed lower toxicity than sorafenib. Compound 5i with 4-(trifluoromenthy)-1H-indazole and 4-(trifluoromenthy) benzene moieties exhibited the most potent anticancer activity. 相似文献
135.
Peter W. Glunz Xiaojun Zhang Yan Zou Indawati Delucca Alexandra H. Nirschl Xuhong Cheng Carolyn A. Weigelt Daniel L. Cheney Anzhi Wei Rushith Anumula Joseph M. Luettgen Alan R. Rendina Mark Harpel Gang Luo Robert Knabb Pancras C. Wong Ruth R. Wexler E. Scott Priestley 《Bioorganic & medicinal chemistry letters》2013,23(18):5244-5248
Aminoisoquinoline and isoquinoline groups have successfully replaced the more basic P1 benzamidine group of an acylsulfonamide factor VIIa inhibitor. Inhibitory activity was optimized by the identification of additional hydrophobic and hydrophilic P′ binding interactions. The molecular details of these interactions were elucidated by X-ray crystallography and molecular modeling. We also show that decreasing the basicity of the P1 group results in improved oral bioavailability in this chemotype. 相似文献
136.
Gang Hua Qi Zhang Rui Zhang Amir M. Abdullah Paul J. Linser Michael J. Adang 《Insect biochemistry and molecular biology》2013,43(2):153-161
In an effort to study the mode of action of Cry11Ba, we identified toxin binding proteins in Anopheles gambiae larval midgut and investigated their receptor roles. Previously, an aminopeptidase (AgAPN2) and an alkaline phosphatase (AgALP1) were identified as receptors for Cry11Ba toxin in A. gambiae. However, an A. gambiae cadherin (AgCad1) that bound Cry11Ba with low affinity (Kd = 766 nM) did not support a receptor role of AgCad1 for Cry11Ba. Here, we studied a second A. gambiae cadherin (AgCad2) that shares 14% identity to AgCad1. Immunohistochemical study showed that the protein is localized on A. gambiae larval midgut apical membranes. Its cDNA was cloned and the protein was analyzed as a transmembrane protein containing 14 cadherin repeats. An Escherichia coli expressed CR14MPED fragment of AgCad2 bound Cry11Ba with high affinity (Kd = 11.8 nM), blocked Cry11Ba binding to A. gambiae brush border vesicles and reduced Cry11Ba toxicity in bioassays. Its binding to Cry11Ba could be completely competed off by AgCad1, but only partially competed by AgALP1. The results are evidence that AgCad2 may function as a receptor for Cry11Ba in A. gambiae larvae. 相似文献
137.
Gang Fang Robert Friesen Frank Lanfermeijer Anja Hagting Bert Poolman Wil N. Konings 《Molecular membrane biology》2013,30(4):297-304
The di-tripeptide transport system (DtpT) of Lactococcus lactis was purified to apparent homogeneity by pre-extraction of crude membrane vesicles with octaethylene glycol monodecyl ether (C10E8), followed by solubilization with n-dodecyl-beta-D-maltoside (DDM) and chromatography on a Ni-NTA resin. The DtpT protein was reconstituted into detergent-destabilized preformed liposomes prepared from E. coli phospholipid/ phosphatidylcholine. A variety of detergents were tested for their ability to mediate the membrane reconstitution of DtpT and their effectiveness to yield proteoliposomes with a high transport activity. The highest activities were obtained with TX100, C12E8 and DM, whereas DDM yielded relatively poor activities, in particular when this detergent was used at concentrations beyond the onset of solubilization of the preformed liposomes. Parallel with the low activity, significant losses of lipid were observed when the reconstitution was performed at high DDM concentrations. This explained at least part of the reduced transport activity as the DtpT protein was highly dependent on the final lipid-to-protein ratios in the proteoliposomes. Consistent with the difference in mechanism of DDM- and TX100-mediated membrane protein reconstitution, the orientation of the DtpT protein in the membrane was random with DDM and inside-in when T100 was used. The methodology to determine the orientation of membrane-reconstituted proteins from the accessibility of cysteines for thiol-specific reagents is critically evaluated. 相似文献
138.
真核生物的基因组以染色质的形式存在,染色质在真核生物的基因表达调控及胚胎发育过程中起重要作用,为表观遗传提供一个重要的信息整合平台.染色质的高级结构,特别是 30 nm染色质的动态变化在基因转录沉默和激活过程中起着重要的调控功能.但是目前对30 nm 染色质纤维的组装及其精细结构的认识还十分有限.本文通过体外表达系统,表达未经修饰的组蛋白,并利用克隆构建的601DNA均一重复序列,通过逐步降低盐离子浓度并加入组蛋白H1或镁离子的方法,体外重组均一的30 nm染色质纤维.并利用镀金属、负染色制样和冷冻电镜制样等手段通过透射式电子显微镜(TEM)对30 nm纤维结构的形成原因、组蛋白H1的作用和核小体重复单位(nucleosome repeat lengths,NRLs)长度对30 nm染色质纤维的影响进行研究.研究结果显示在组蛋白H1或二价镁离子存在的情况下,均可形成30 nm染色质纤维.其形成的染色质拓扑结构有所不同.统计分析表明,不同长度核小体重复单位(NRLs)形成的染色质纤维直径有所不同(P < 0.05).同时,我们得到了较为均一的冷冻电镜样品,为进一步研究30 nm染色质纤维的高级结构及理解体内染色质存在的形式及动态过程打下了较好的基础. 相似文献
139.
140.
Ling Wang Lian Meng Liu Zhi Gang Wang Shi Wen Huang 《Journal of Phytopathology》2013,161(11-12):753-762
One hundred and eighty isolates of Rhizoctonia solani AG1‐IA, the causal agent of rice sheath blight, were obtained from six locations in southern China. The genetic structure of R. solani isolates was investigated using random amplified polymorphic DNA (RAPD) markers, and a considerable genetic variation among R. solani isolates was observed. Most of the genetic diversity was distributed within populations, rather than among them. The distribution pattern of the genetic variation of R. solani appears to be the result of high gene flow (Nm) and low‐genetic differentiation among populations. The aggressiveness of R. solani was visually assessed by rice seedlings of five different cultivars in the glasshouse. All isolates tested were found to induce significantly different levels of disease severity, reflecting considerable variation in aggressiveness. The isolates were divided into highly virulent, moderately virulent and weakly virulent groups, and the moderately virulent isolates were dominant in R. solani population. No significant correlation was observed among the genetic similarity, pathogenic aggressiveness and geographical origins of the isolates. Information obtained from this study may be useful for breeding for improved resistance to sheath blight. 相似文献