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1.
Collagens are the most abundant proteins in the extracellular matrix. They provide a framework to build organs and tissues and give structural support to make them resistant to mechanical load and forces. Several intra‐ and extracellular modifications are needed to make functional collagen molecules, intracellular post‐translational modifications of proline and lysine residues having key roles in this. In this article, we provide a review on the enzymes responsible for the proline and lysine modifications, that is collagen prolyl 4‐hydroxylases, 3‐hydroxylases and lysyl hydroxylases, and discuss their biological functions and involvement in diseases. 相似文献
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Hannah C. Nordhues Anjali Bhagra Natya N. Stroud Jennifer A. Vencill Carol L. Kuhle 《Mayo Clinic proceedings. Mayo Clinic》2021,96(7):1907-1920
The coronavirus disease 2019 (COVID-19) pandemic has rapidly created widespread impacts on global health and the economy. Data suggest that women are less susceptible to severe illness. However, sex-disaggregated data are incomplete, leaving room for misinterpretation, and focusing only on biologic sex underestimates the gendered impact of the pandemic on women. This narrative review summarizes what is known about gender disparities during the COVID-19 pandemic and the economic, domestic, and health burdens along with overlapping vulnerabilities related to the pandemic. In addition, this review outlines recommended strategies that advocacy groups, community leaders, and policymakers should implement to mitigate the widening gender disparities related to COVID-19. 相似文献
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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:比较康莱特注射液联合紫杉醇及紫杉醇单纯化疗治疗晚期恶性胸腺瘤的不良反应和疗效。方法:2013年8月至2017年12月,经病理学和免疫组化确诊为恶性胸腺瘤并在我院肿瘤中心进行姑息性化疗的患者68例。康莱特注射液联合化疗为观察组(37例);单纯化疗为对照组(31例)。28天为一周期,共化疗4周期。结果:两组患者均无人发生过敏反应。观察组可有效减轻患者化疗不良反应:恶性、呕吐、四肢麻木、关节肌肉酸痛和白细胞下降(P<0.05),可以有效减轻患者胸闷症状和全身疼痛(P<0.05),在肿瘤控制方面,康莱特联合化疗的疗效较单纯化疗稍好,但均未见有统计学差异(P>0.05)。结论:康莱特注射液联合紫杉醇治疗晚期胸腺瘤,具有减轻患者疼痛、减轻化疗不良反应,从而提高患者化疗依从性的作用,值得临床进一步推广和研究。 相似文献
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目的:了解2011-2017年四川省三州地区卫生人力资源配置现状,为三州地区卫生人力资源的合理配置提供参考。方法:利用千人卫生人力资源拥有量指标、基尼系数和卫生人力资源密度指数(HRDI)分析卫生人力资源配置现状及其公平性。结果:三州地区千人卫生人力资源拥有量呈增长趋势;基尼系数大多超过0.4,仅护士按人口分布的基尼系数较小;卫生人力资源密度指数较小,需要量、缺乏量及缺乏比例均较大。结论:三州地区卫生人力得到一定程度改善;但配置公平性较差,尤其按地理、经济分布很不均衡;医护人员短缺,需要重点投入。 相似文献
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目的 按照国家计划抽验要求,评价国内不同企业生产的注射用盐酸柔红霉素的质量。方法 按国家标准检验与探索性研究相结合,对抽验样品进行检验,对检验结果进行统计分析。结果 共抽取样品17批次,按国家标准检验合格率100.0%。探索性研究对主要杂质的来源与结构进行了研究;建立溶液的澄清度检查方法;对包材相容性及稳定性进行了考察。结论 目前国内注射用盐酸柔红霉素总体质量较好;现行标准有待进一步提高,建议现行标准修订有关物质检查方法,增加特定杂质的控制,增加溶液的澄清度检查;建议企业优化生产工艺,以提高产品质量。 相似文献
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Prevalence of HER2 Expression and Its Correlation with Clinicopathological Parameters in Gastric or Gastroesophageal Junction Adenocarcinoma in North-East Indian Population 下载免费PDF全文
Partha S RoyTomar NyoduMunlima HazarikaB J SaikiaC BhuyanAmit InamdarC W NyutheB BorthakurJ D Sharma 《Asian Pacific journal of cancer prevention》2019,20(4):1139-1145
Objective: Human epidermal growth factor receptor 2 (erbb2/HER2) overexpression, has now been implicatedin advanced gastric and gastroesophageal junction cancers. The study was conducted to determine the rate of HER2positivity in patients with locally advanced or metastatic gastric and gastroesophageal adenocarcinoma in North-EastIndia and to assess the impact of various demographic and clinical parameters on HER2 positivity. Methods: A total of68 patients of age >18 years of gastric and gastroesophageal adenocarcinoma diagnosed on histopathological examinationfrom September 2016 to February 2018 at Dr B Borooah Cancer Institute, Assam were enrolled for the observational(epidemiological) study. All patients were subjected to the HER2 immunohistochemistry test using a FDA-approved,standardized test kit. HER2 expression was correlated with various demographic and clinicopathological parameters.Results: The overall rate of HER2 positivity in the population studied was 56% (n=38). The rate was non-significantlyhigher in male, older age group (>60 years) and Hindu population. Similarly, HER2 positivity rate was higher in patientswith well differentiated histology and was more common in patients with stage II and III diseases, but neither of theassociations is statistically significant. HER2 positivity rate was significantly higher in proximal and in GEJ tumours(56% versus 44%, P=0.002). Conclusion: HER2 overexpression was evident in 56% of the North-East Indian patientswith locally advanced and metastatic gastric and gastroesophageal adenocarcinoma. The overexpression correlatedsignificantly with primary tumour site. Routine testing of gastric and gastroesophageal tumours for HER2 expressionis recommended to provide a therapeutic advantage in Indian patients. 相似文献