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991.
通过对传统的双向电泳方法进行改进与优化,得到了一种适合于分析植物叶 片蛋白质的双向电泳新方法。用改进后的方法对水稻不同时期成熟叶片蛋白质进行双向电泳分离,结果显示其稳定性和重复性好,分辨率较高,经考马斯亮蓝染色后可分辨出300多个蛋白质(肽)点。它们的等电点和分子量主要分布于pI4.1-8.2和10-100kDa之间。本文还就实验过程中出现的一些技术问题进行了讨论。 Abstract:Base on the method of O farrell,an improved procedure for the two-dimensional gel electrophoresis of leaf proteins is presented.The two-dimensional separation of proteins from the mature leaves of different developmental stages of rice provides distinct and steady results.The detected protein(peptide)spots stained by Coomassie brilliant blue R-250 are more than 300,with isoelectric points(pI)ranging from 4.1 to 8.2 and molecular weights(MW)from 10 kDa to 100 kDa.  相似文献   
992.
火炬树的组织培养及植株再生   总被引:6,自引:0,他引:6  
植物名称 火炬树 (Rhustyphina)。2 材料类别 茎尖。3 培养条件 培养基 :( 1 )MS 6 BA 2 .0mg·L-1(单位下同 ) ;( 2 )MS 6 BA 1 .0 NAA 0 .1 ;( 3)MS。以上培养基均加蔗糖 30g·L-1、琼脂 7g·L-1,pH 6~ 6 .5 ;培养温度白天 2 5~ 30℃ ,夜间 1 5~ 2 0℃ ;光照时间 1 2h·d-1,光照度 2 0 0 0~ 2 5 0 0lx。4 生长与分化情况4.1 芽的分化 剪取健壮的枝条 ,先将枝条切成小段 ,每段带一个芽 ,在无菌条件下 ,将切段浸入 70 %酒精中 ,经数秒钟 ,再用 0 .1 %升汞溶液浸泡 8min ,然后…  相似文献   
993.
Cytoskeleton in Pollen and Pollen Tubes of Ginkgo biloba L.   总被引:4,自引:0,他引:4  
The distribution of F-actin and microtubules was investigated in pollen and pollen tubes of Ginkgo biloba L. using a confocal laser scanning microscope after fluorescence and immunofluorescence labeling. A dense F-actin network was found in hydrated Ginkgo pollen. When Ginkgo pollen was germinating,F-actin mesh was found under the plasma membrane from which the pollen tube would emerge. After pollen germination, F-actin bundles were distributed axially in long pollen tubes of G. biloba. Thick F-actin bundles and network were found in the tip of the Ginkgo pollen tube, which is opposite to the results reported for the pollen tubes of some angiosperms and conifers. In addition, a few circular F-actin bundles were found in Ginkgo pollen tubes. Using immunofluorescence labeling, a dense microtubule network was found in hydrated Ginkgo pollen under confocal microscope. In the Ginkgo pollen tube, the microtubules were distributed along the longitudinal axis and extended to the tip. These results suggest that the cytoskeleton may have an essential role in the germination of Ginkgo pollen and tube growth.  相似文献   
994.
Several reviews have focused on the nature of HIV infection and its spread in various geographical regions of China. In contrast, this review provides a comprehensive update on the prevalence of multiple HIV- 1 subtypes, consequent emergence of recombinant and novel forms of HIV- 1 in China, and the implications this may have on HIV diversity and the development of effective vaccines. In addition it also examines the dissemination of primary drug resistance in therapy naive patients, as well as co-infections with two other important viruses-hepatitis B and C. The main purpose of this review is to provide a current snapshot of HIV-1 pathogenesis in China and possibly shed some light on the future of HIV evolution, and potential challenges for future vaccine and anti-retroviral therapeutics against HIV strains in this area.  相似文献   
995.
A female-specific protein, vitellogenin (Vg), and its corresponding egg vitellin (Vt) are identified in the ectoparasitic wasp Nasonia vitripennis. Both native Vt and Vg have a molecular mass of about 350 kDa, which is composed of two subunits of approximately 190 kDa and 165 kDa under reducing and denaturing conditions (sodium dodecyl sulfate-polyacrylamide gel electrophoresis). An indirect sandwich enzyme-linked immunosorbent assay developed with both monoclonal and polyclonal antibodies against N. vitripennis Vt. Vg was first detected in the hemolymph on the 10th day after parasitism, and was first observed in oocytes on the 12th day. In adults deprived of food, the highest hemolymph Vg level occurred at the time of adult eclosion and the highest level of Vt in ovaries was found at 30 h after eclosion. In contrast, feeding adults with 20% sucrose resulted in the reduction of Vt uptake by ovaries and the extension of life span, but had little effect on Vg production. Deprived of hosts, starvation of female wasps had no significant effects on ovariole growth and oocyte maturation before the wasps died. However, starvation of female wasps supplied with hosts accelerated the wasps laying progeny into hosts, but resulted in a decrease of total progeny production by comparison with wasps fed with 20% sucrose.  相似文献   
996.
China's Free ART Program was initiated in 2002 as an emergency response to save and improve the lives of AIDS patients living mainly in impoverished rural regions of central China. With little experience in HIV/AIDS treatment and care and resource limitations, China's efforts to provide widespread access to free antiretroviral therapy has been a process fraught with difficulty. However, the Free ART Program is progressing from an emergency response to a standardized treatment and care system. The development of national guidelines, training programs, a laboratory support network, a national patient database, programs for special populations such as children and patients living with coinfections, and operational research has improved the scope and quality of the free treatment program. As of June 30, 2005, a total of 19,456 patients in 28 provinces, autonomous regions, and special municipalities had received free ART. Challenges stemming from the nature of China's health system and patient population persist, but with strong government support and a diverse set of resources, China has the capacity to overcome these challenges and to provide nationwide access to high quality treatment and care.  相似文献   
997.
The region between the preexisting and nascentmembranes of a cleaving Rana egg is a dense protrusionregion of nearly 40μm wide at 180°stage.Later,thisregion differentiate,into an upper part,a strip withlong, branched and randomly distributed protrusionswhich are derived largely from the preexistingmembrane,and a lower part,a band with microvilli.During 4-and 8-cel1 stages,the strip is almost vanishedand microvilli in the band is shortened.The nascentmembrane is smooth at the 180°stage,then a rough areaappears below the smooth region and quickly expands.Wheat germ agglutinin which can bind to preexistingmembrane interrupts the development of the regionbetween the preexisting and nascent membranes.Detergent,Brij,having the property to increase the areaof nascent membrane,does not interrupt the developmentof the region between the preexisting and nascentmembranes.  相似文献   
998.
999.
1000.
Cannabinoid receptor type 2(CB2)activation is recently reported to promote proliferation of some types of resident stem cells(e.g.,hematopoietic stem/progenitor cell or neural progenitor cell).Resident cardiac progenitor cell(CPC)activation and proliferation are crucial for endogenous cardiac regeneration and cardiac repair after myocardial infarction(MI).This study aims to explore the role and possible mechanisms of CB2receptor activation in enhancing myocardial repair.Our results revealed that CB2receptor agonist AM1241 can significantly increase CPCs by c-kit and Runx1 staining in ischemic myocardium as well as improve cardiomyocyte proliferation.AM1241 also decreased serum levels of MDA,TNF-αand IL-6 after MI.In addition,AM1241 can ameliorate left ventricular ejection fraction and fractional shortening,and reduce fibrosis.Moreover,AM1241 treatment markedly increased p-Akt and HO-1 expression,and promoted Nrf-2 nuclear translocation.However,PI3K inhibitor wortmannin eliminated these cardioprotective roles of AM1241.In conclusion,AM1241 could induce myocardial regeneration and improve cardiac function,which might be associated with PI3K/Akt/Nrf2 signaling pathway activation.Our findings may provide a promising strategy for cardiac endogenous regeneration after MI.  相似文献   
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