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101.
102.
The occurrence and development of ischemic stroke are closely related to cerebral blood flow. Real‐time monitoring of cerebral perfusion level is very useful for understanding the mechanisms of the disease. A wide field of view (FOV) is conducive to capturing lesions and observing the progression of the disease. In this paper, we attempt to monitor the whole‐brain microcirculation in middle cerebral artery occlusion (MCAO) rats over time using a wide FOV swept‐source OCT (SS‐OCT) system. A constrained image registration algorithm is used to remove motion artifacts that are prone to occur in a wide FOV angiography. During ischemia, cerebral perfusion levels in the left and right hemispheres, as well as in the whole brain were quantified and compared. Changes in the shape and location of blood vessels were also recorded. The results showed that the trend in cerebral perfusion levels of both hemispheres was highly consistent during MCAO, and the position of the blood vessels varied over time. This work will provide new insights of ischemic stroke and is helpful to assess the effectiveness of potential treatment strategies.   相似文献   
103.
人心肌肌球蛋白轻链1的克隆,表达纯化和单抗制备   总被引:2,自引:2,他引:2  
报道了中国人心肌肌球蛋白轻链1cDNA的核苷酸序列,并由此推算的氨基酸序列。与国外发表的人心肌肌球蛋白轻链的氨基酸序列比较,发现有两处差异,即在24位,由谷氨酸变为丙氨酸,则从98位起至101位有4个氨基酸序列的连续差异,即由天冬酰胺-精氨酸-丝氨酸-赖氨酸变为赖氨酸-脯氨酸-精氨酸-谷氨酰妥,推测可能是由于人种差异而引起的。利用该cDNA在大肠杆菌内的表达产物,已获得一株高效的抗中国人心肌肌球蛋  相似文献   
104.
105.
Liu  Xi  Ding  Li  Yuan  Jing  Liao  Jian  Duan  Lian  Wang  Wenfei  Tan  Weiguo  Yu  Weiye  Zhou  Boping  Chen  Xinchun  Yang  Zheng 《中国病毒学》2019,34(3):334-337
<正>Dear Editor,H7 N9 is a recently identified subtype of influenza A virus that caused a major outbreak in humans in China in 2013.According to the latest data provided by the Chinese Center for Disease Control and Prevention(http://www.moh.gov.cn/zwgk/yqbb3/ejlist.shtml, updated on October 31, 2018),the mortality rate of H7 N9 infections in China amounts to  相似文献   
106.

Background  

In S. cerevisiae, the mitotic exit network (MEN) proteins, including the Polo-like protein kinase Cdc5 and the protein phosphatase Cdc14, are required for exit from mitosis. In pre-anaphase cells, Cdc14 is sequestered to the nucleolus by Net1 as a part of the RENT complex. When cells are primed to exit mitosis, the RENT complex is disassembled and Cdc14 is released from the nucleolus.  相似文献   
107.

Background

Insertions and deletions (indels) are the most abundant form of structural variation in all genomes. Indels have been increasingly recognized as an important source of molecular markers due to high-density occurrence, cost-effectiveness, and ease of genotyping. Coupled with developments in bioinformatics, next-generation sequencing (NGS) platforms enable the discovery of millions of indel polymorphisms by comparing the whole genome sequences of individuals within a species.

Results

A total of 1,973,746 unique indels were identified in 345 maize genomes, with an overall density of 958.79 indels/Mbp, and an average allele number of 2.76, ranging from 2 to 107. There were 264,214 indels with polymorphism information content (PIC) values greater than or equal to 0.5, accounting for 13.39 % of overall indels. Of these highly polymorphic indels, we designed primer pairs for 83,481 and 29,403 indels with major allele differences (i.e. the size difference between the most and second most frequent alleles) greater than or equal to 3 and 8 bp, respectively, based on the differing resolution capabilities of gel electrophoresis. The accuracy of our indel markers was experimentally validated, and among 100 indel markers, average accuracy was approximately 90 %. In addition, we also validated the polymorphism of the indel markers. Of 100 highly polymorphic indel markers, all had polymorphisms with average PIC values of 0.54.

Conclusions

The maize genome is rich in indel polymorphisms. Intriguingly, the level of polymorphism in genic regions of the maize genome was higher than that in intergenic regions. The polymorphic indel markers developed from this study may enhance the efficiency of genetic research and marker-assisted breeding in maize.

Electronic supplementary material

The online version of this article (doi:10.1186/s12864-015-1797-5) contains supplementary material, which is available to authorized users.  相似文献   
108.
Choosing appropriate approaches is a key to successfully using biological control measures to accelerate the recovery of eutrophic waterbodies. In this study, we used three biomanipulation approaches—including introducing filter-feeding bivalves, stocking planktivorous fish, replanting submerged macrophytes—as well as an approach that combined all three of these methods in order to investigate their effects on water quality and plankton communities within simulation experiment systems. The experimental results showed that only stocking filter-feeding bivalves or fish could not significantly control the total algal biomass and water nutrient concentrations compared to those of the controls. The cladoceran biomasses were reduced under the treatments of stocking filter-feeding bivalves or fish. However, replanting macrophytes and a combined biological restoration approach could significantly reduce the algal biomass and the nutrient content, and both of these methods increased cladoceran biomass. The results of factor analysis of ten environmental parameters suggested that a combined biological restoration treatment was the most effective at controlling the algal biomass and reducing the nutrient content. In conclusion, combination of biological restoration measures was the best treatment out of the three treatments that were tested, and we suggest that more whole-lake scale experiments are needed. Additionally, designing a combined approach should not be a simple superposition of individual measures, but the measures should be complementary to each other.  相似文献   
109.
In this study, we investigated the metabonomic profiles of Apostichopus japonicus using an LC-MS-based method in conjunction with multivariate data analysis. Based on the PLS-DA model, 85 differential metabolites (VIP value >1.0) were obtained from viscera and body wall samples. The MS/MS and NMR experiments were used for the qualitative identification of the characteristic peaks. Sphingoid-based nucleoside analogues were the main components in Chinese A. japonicus viscera. Our findings demonstrate that A. japonicus viscera contain a large number of compounds that may have applications as nutraceuticals or pharmaceuticals.  相似文献   
110.
基于MapObjects的稻水象甲疫情呈报地理信息系统   总被引:1,自引:0,他引:1       下载免费PDF全文
【背景】稻水象甲是我国最具危害性的外来入侵物种之一,自1996年传人福建省以来,对当地农民增产、增收及粮食安全生产构成了极大威胁。【方法】依据1996~2008年福建省稻水象甲发生面积数据,结合GIS技术和数据库管理技术,以VisualBasic6.0为开发语言,Access2003为Geodatabase空间数据库、MapObjects2.0为地图开发组件,开发了福建省稻水象甲疫情呈报系统。【结果】本系统实现了稻水象甲疫情实时呈报、基于GIS地理分布查询、专题地图制作等功能。专题地图制作和可扩展性是本系统的两大特点,用户不需要专业的GIS和计算机知识,就可以生成一套适合自己的植物疫情呈报系统,为农业病虫害防治工作提供疫情呈报与GIS查询服务。【结论与意义】本系统为稻水象甲的实时监测、防控工作提供了管理工具;界面友好、操作简单且可扩展性良好,便于基层普及应用。  相似文献   
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