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Summary To investigate whether intestinal calcium absorption parallels that of sodium following extracellular fluid volume expansion, the effects of saline loading on intestinal transport of calcium. sodium and water were studied in rats by perfusing jejunal loops in situ.After calcium-free saline infusion net calcium absorption was reversed similar to that of sodium and water and net secretion occurred. Concurrently, blood-to-lumen (b-l) calcium flux, measured using45Ca, increased significantly (P<0.001). Following expansion with calcium-containing Ringer a similar reversal of net calcium, sodium and water flux was also observed. Again, the b-l calcium flux increased but to a significantly lesser extent (P<0.05). Plasma ionized calcium remained unchanged after calcium-rich Ringer loading, but decreased significantly (P<0.001) when calcium was omitted from the solution. Plasma immunoreactive parathyroid hormone was unchanged after expansion with the calcium containing solution but increased following calcium-free infusion.It is concluded that after extracellular fluid volume expansion: 1. net jejunal calcium absorption is decreased; 2. the decrease parallels that of sodium and water; 3. b-l calcium transport is enhanced to a greater degree by calcium-free Ringer infusion than by a calcium-rich solution. This difference could be the result of increased parathyroid hormone secretion.  相似文献   
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晚明时期 ,在吴江地区出现了一个以叶绍袁、沈宜修及其子女为核心的文学团体 ,成就杰出。特别是女性文学 ,更令人聒目相看 ,这与叶绍袁进步的女性文学观及其妻女杰出的文学才华密不可分 ;也与吴江地区高度的文学水平密不可分  相似文献   
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目的:研究复合应用高渗氯化钠溶液和琥珀酰明胶对失血性休克犬的血流动力学和氧转运的影响。方法:18只犬麻醉后气管内插管,自主呼吸空气。经股动脉放血至平均动脉压为6.7kPa并维持2h。分为3组,每组6只。氯化钠溶液组:于5min内输入失血量10%的75g·L-1NaCl;高渗氯化钠溶液/琥珀酰明胶组:于5min内输入失血量10%的75g·L-1NaCl/琥珀酰明胶;乳酸钠林格氏液组:于20min内输入2.5倍失血量的乳酸钠林格氏液。结果:3组的血流动力学参数在治疗后都有显著的改善。高渗氯化钠溶液/琥珀酰明胶对血流动力学和氧供的作用时间较HSC持久。高渗氯化钠溶液/琥珀酰明胶组的胶体渗透压明显高于其它两组。各组氧摄取率和血浆乳酸浓度无显著差异。结论:失血性休克早期应用小容量75g·L-1NaCl/琥珀酰明胶可改善血流动力学和氧供需平衡。  相似文献   
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《Vaccine》2022,40(30):4017-4025
Since 2019, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection resulting in the coronavirus disease 2019 (COVID-19) has afflicted hundreds of millions of people in a worldwide pandemic. Several safe and effective COVID-19 vaccines are now available. However, the rapid emergence of variants and risk of viral escape from vaccine-induced immunity emphasize the need to develop broadly protective vaccines. A recombinant plant-derived virus-like particle vaccine for the ancestral COVID-19 (CoVLP) recently authorized by Canadian Health Authorities and a modified CoVLP.B1351 targeting the B.1.351 variant (both formulated with the adjuvant AS03) were assessed in homologous and heterologous prime-boost regimen in mice. Both strategies induced strong and broadly cross-reactive neutralizing antibody (NAb) responses against several Variants of Concern (VOCs), including B.1.351/Beta, B.1.1.7/Alpha, P.1/Gamma, B.1.617.2/Delta and B.1.1.529/Omicron strains. The neutralizing antibody (NAb) response was robust with both primary vaccination strategies and tended to be higher for almost all VOCs following the heterologous prime-boost regimen.  相似文献   
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Plastic bronchitis (PB), although a rare cause of airway obstruction, has mortality rates up to 50% in children after Fontan-type cardiac surgery. We present the case of an 18-month-old female patient with PB following pneumonia. At 6 months of age, the patient underwent the Glenn procedure due to functionally univentricular heart. Fiberoptic bronchoscopy revealed complete blockage of the left bronchus by mucoid casts. Pharmacotherapy consisted of glucocorticosteroids, azithromycin, and enalapril maleate. The child also received nebulized 3% NaCl solution, which proved to be beneficial. In children submitted to Fontan-type procedures, physicians must be alert for PB, which can be triggered by respiratory tract infection.  相似文献   
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As of December 2015 there were 37 million persons living with HIV/AIDS (PLWHAs), 70% of whom are in sub-Saharan Africa. Ghana, which contributes a relatively small number to Africa’s HIV burden, has a generalised HIV epidemic. The current national prevalence is 1.47%. Agormanya, one of the HIV sentinel sites in the county and where this study was conducted, has current prevalence of 11.6%. This makes it critical to explore how persons infected with HIV manage their lives, especially in the midst of entrenched stigma and discrimination. However, available information on how PLWHAs in sub-Saharan Africa handle their day-to-day lives mostly dwell on food and nutrition. Thus, there is dearth of information on how PLWHAs in Ghana particularly handle the circumstances of their daily lives which are mostly coloured by their HIV-positive statuses, given their stigmatised identity. We explore how PLWHAs respond to the experiences and challenges of living with HIV/AIDS in Lower Manya Krobo, consistently most HIV-infected district in Ghana. Data were collected from 38 combined purposive and randomly selected HIV-positive persons in two leading hospitals (St Martins Depores Agormanya and Atua Government hospitals which provide specialised HIV care in the district. Using in-depth interviews, we studied how PLWHAs managed their routine livelihoods in the midst of extreme stigma. We combined the social capital and resilience theoretical frameworks to show that our respondents were mostly resilient and strategically mostly drew upon extended family social support to cope with their livelihood challenges. We recommend that community opinion leaders and other stakeholders sensitise community members in Lower Manya Krobo to better understand the mode of HIV infection and encourage/strengthen family and community cohesion and social support.  相似文献   
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目的 研究64层螺旋CT使用低剂量对比剂联合生理盐水在CTA中对脑动脉瘤的应用价值.方法 对临床疑有脑动脉瘤51例患者分为三组:甲组90ml对比剂不用生理盐水冲洗;乙组、丙组分别使用70ml、50ml对比剂之后用相同流速生理盐水40ml冲洗.对比剂流速为5.0ml/s.当颈内静脉显影的一刹那开始扫描.利用工作站软件进行图像处理,评估三组血管图像质量及动脉瘤显示情况.结果 三组病例动脉瘤的灵敏度、特异性在统计学上没有明显差异,甲组动静脉均显示很好,CT值较高.丙组动脉显示良好,静脉少,污染轻,血管CT值略低.乙组居于二者之间.结论 使用低剂量对比剂50ml+40ml生理盐水以5.0ml/s流率注射,不仅可以得到理想的图像,还是一种安全、快速、经济的检查方法.  相似文献   
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