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1.
Patrick W. Keeley Mikayla C. Lebo Jordan D. Vieler Jason J. Kim Ace J. St. John Benjamin E. Reese 《The Journal of neuroscience》2021,41(1):103
Amacrine cells of the retina are conspicuously variable in their morphologies, their population demographics, and their ensuing functions. Vesicular glutamate transporter 3 (VGluT3) amacrine cells are a recently characterized type of amacrine cell exhibiting local dendritic autonomy. The present analysis has examined three features of this VGluT3 population, including their density, local distribution, and dendritic spread, to discern the extent to which these are interrelated, using male and female mice. We first demonstrate that Bax-mediated cell death transforms the mosaic of VGluT3 cells from a random distribution into a regular mosaic. We subsequently examine the relationship between cell density and mosaic regularity across recombinant inbred strains of mice, finding that, although both traits vary across the strains, they exhibit minimal covariation. Other genetic determinants must therefore contribute independently to final cell number and to mosaic order. Using a conditional KO approach, we further demonstrate that Bax acts via the bipolar cell population, rather than cell-intrinsically, to control VGluT3 cell number. Finally, we consider the relationship between the dendritic arbors of single VGluT3 cells and the distribution of their homotypic neighbors. Dendritic field area was found to be independent of Voronoi domain area, while dendritic coverage of single cells was not conserved, simply increasing with the size of the dendritic field. Bax-KO retinas exhibited a threefold increase in dendritic coverage. Each cell, however, contributed less dendrites at each depth within the plexus, intermingling their processes with those of neighboring cells to approximate a constant volumetric density, yielding a uniformity in process coverage across the population.SIGNIFICANCE STATEMENT Different types of retinal neuron spread their processes across the surface of the retina to achieve a degree of dendritic coverage that is characteristic of each type. Many of these types achieve a constant coverage by varying their dendritic field area inversely with the local density of like-type neighbors. Here we report a population of retinal amacrine cells that do not develop dendritic arbors in relation to the spatial positioning of such homotypic neighbors; rather, this cell type modulates the extent of its dendritic branching when faced with a variable number of overlapping dendritic fields to approximate a uniformity in dendritic density across the retina. 相似文献
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目的 建立一种能够快速鉴定人参和西洋参的双重实时荧光PCR方法。方法 通过对人参属及其近似种基因序列的分析比对,设计特异性的引物探针,建立双重实时荧光PCR检测方法。PCR反应体系为Premix Ex Taq (Probe qPCR) 10 μL,人参上下游引物各0.5 μL,西洋参上下游引物各0.3 μL,人参与西洋参特异性探针各0.4 μL,DNA模板2 μL,灭菌去离子水补至20 μL。反应条件为95℃预变性30 s;然后以95℃变性5 s,60℃退火延伸30 s进行40个循环。应用该方法测试了27份DNA样品,包括7份人参、6份西洋参、4份人参与西洋参混合样、10份其他人参属样品及其他常见中药材样品的DNA,以确定该方法的特异性。将人参与西洋参样品DNA混合后10倍稀释成不同浓度后进行检测,用以确定该方法的灵敏度。结果 人参及西洋参样品均在特定的荧光通道下出现典型的阳性扩增曲线,人参与西洋参混合样品均同时出现两条阳性扩增曲线,其它对照样品及空白对照均没有出现阳性扩增曲线。灵敏度检测结果显示该方法检测人参及西洋参的最低检测限均为2 pg DNA/反应。结论 本实验建立的双重实时荧光PCR方法能够同时快速、准确、灵敏地鉴别出人参和西洋参。 相似文献
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Discordant Electrocardiogram Left Ventricular Wall Thickness and Strain Findings in Influenza Myocarditis 下载免费PDF全文
Nael Hawwa M.D. Zoran B. Popovic M.D. Ph.D. Hussain A. Isma'eel M.D. 《Echocardiography (Mount Kisco, N.Y.)》2015,32(12):1880-1884
A 42‐year‐old man presented with a viral prodrome and tested positive for influenza A. He rapidly deteriorated developing cardiogenic shock, rhabdomyolysis, and acute kidney injury. Patient improved 1 week later with supportive measures including vasopressors, inotropes, and an intraaortic balloon pump. We report this case as it highlights the discordance between echocardiographic ventricular wall thickening as a result of myocardial edema, and electrocardiographic findings at presentation, with a reversal in findings at time of resolution. Additionally, there was some suggestion of a regional pattern to the reduced longitudinal strain. 相似文献
7.
Yulong Lian Jing Xiao Chen Zhang Suzhen Guan Fuye Li Hua Ge 《Archives of environmental & occupational health》2016,71(2):74-84
The present study compared the level of occupational strain and work ability among Han, Hui, Uygur, Hui, and Kazakh teachers, and explored ethnic differences based on the associations of psychosocial factors at work, occupational strain, and work ability. A cross-sectional survey was conducted among 2,941 teachers in primary and secondary schools in Xinjiang Province, China. Psychosocial factors, occupational strain, and work ability were measured using the Occupation Stress Inventory—Revised Edition (OSI-R) and Work Ability Index. Han and Hui teachers experienced reduced work ability compared with Uygur and Kazakh teachers, and this finding was caused, in part, by exposure to psychosocial factors at work. The vocational and psychological strains caused by these factors play an important role in reduced work ability among all ethnic teacher groups. The findings indicate the importance of taking action to reduce occupational strain for promoting teachers' work ability in multiethnic workplaces. 相似文献
8.
Erin C. Tully Jackson M. Gray Sherryl H. Goodman Stephen Nowicki Jr. 《Early child development and care》2016,186(12):1939-1951
Children who expect they can bring about good outcomes and avoid bad outcomes tend to experience more personal successes. Little is known about factors that contribute to these ‘control expectancies’. The purpose of the present study was to determine whether children's internal control expectancies occur in the context of parents’ internal control expectancies, low family strain, and high family cohesiveness and whether these factors are more strongly related to daughters’ than sons’ control expectancies. A community sample of 85 children aged 9–11 years and their parents (85 mothers; 63 fathers) completed rating scales. Fathers’ more internal control expectancies and mothers’ reports of fewer family strains were associated with daughters’ but not sons’ greater internal control expectancies, and greater family cohesiveness was related to both daughters’ and sons’ internal control orientations. These findings suggest that family factors may contribute to children's, particularly daughters’, development of internal control expectancies. 相似文献
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Assessment of Myocardial Infarct Size by Three‐Dimensional and Two‐Dimensional Speckle Tracking Echocardiography: A Comparative Study to Single Photon Emission Computed Tomography 下载免费PDF全文
10.
Breast Elastography: How to Perform and Integrate Into a “Best-Practice” Patient Treatment Algorithm
Breast elastography has been available for more than 15 years but is not widely incorporated into clinical practice. Many publications report extremely high accuracy for various breast elastographic techniques. However, results in the literature are extremely variable. This variability is most likely due to variations in technique, a relatively steep learning curve, and variability in methods between vendors. This article describes our protocol for performing breast elastography using both strain elastography and shear wave elastography, which produces high sensitivity and specificity. Additionally, we will describe the most commonly known false-positive and false-negative lesions as well as how to detect them. 相似文献