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31.
目的:探讨聚肌苷酸胞苷酸(polyinosinic polycytidylic acid,polyI:C)注射C57小鼠对其自身抗体产生的影响.方法:50只6~8周龄雌性C57小鼠随机分为药物组和阴性对照组(n=25),药物组按5 mg/kg剂量腹腔注射polyI:C,每周注射2次,阴性对照组注射等量PBS,每4周每组取5只小鼠眼眶采血,间接免疫荧光法测定血清抗核抗体(ANA)和抗线粒体抗体(AMA)水平.结果:随着药物注射次数的增多,药物组在第8周ANA阳性率达到100%,最高滴度达到1:10 000,阴性对照组随着饲养时间的延长也出现ANA阳性,并且在12周达到100%,但是始终没有出现滴度为1:10 000的高滴度自身抗体;随着药物注射次数的增多,药物组血清AMA阳性率逐渐增高,16周达到80%,最高滴度达到1:10 000,对照组未出现AMA阳性.结论: polyI:C注射C57小鼠可以刺激机体产生自身抗体ANA和AMA,并且其对AMA的诱导具有特异性. 相似文献
32.
目的 应用micro-CT研究尾吊大鼠胫骨骨小梁微结构的变化,以此评价间断性水平位站立对抗模拟失重导致的骨微结构退化的效果.方法 24只SD雄性大鼠随机等分为3组:对照组(CON组)、尾吊组(SUS组)、水平位站立对抗组(ST组).尾吊组大鼠始终保持约30°头低位及后肢自由悬垂不负重状态,水平位站立对抗组在尾吊处理的基础上,大鼠每天固定时间水平站立1 h.实验3周后处死各组大鼠,取其右侧胫骨行micro CT扫描及三维重建,对其骨微结构进行定量分析.结果 选定感兴趣区(ROI)行定量分析及三维可视化后,与CON组相比,SUS组胫骨骨体积分数(BVF)、骨小梁数量(Tb.N)、骨小梁厚度(Tb.Th)均显著降低,而骨表面积/体积(BS/BV)、骨小梁间隙(Tb.Sp)及骨小梁模式因子(Trabecular Pattern Factor,TPF)均显著升高;ST组的变化介于SUS组和CON组之间;三维可视化图像结果与物理参数结果趋势一致.应用One-Way ANOVA分析及多重比较LSD-t检验,三组各参数之间统计学差异显著(P<0.05).结论 间断性水平位站立可明显减弱尾吊大鼠胫骨的微结构退化和骨质丢失,而micro CT可以有效地辨别胫骨松质骨微结构的精细变化. 相似文献
33.
İpek Ulu Yasemin Çekmez Şule Yıldırım Köpük Nida Özer Eser Evrim Yoğurtçuoğlu Pınar Anğın 《The journal of maternal-fetal & neonatal medicine》2019,32(15):2543-2546
Purpose: The aim of the study was to investigate whether maternal serum TSP-1 level was associated with PE.Materials and methods: In our case control study, 84 pregnant women in the third trimester were included. Forty-one of them were healthy and 43 of them were with the diagnosis of PE. The diagnosis was based on the definitions of the National High Blood Pressure Education Program working Group on High Blood Pressure in Pregnancy. Preeclamptic patients were divided into two subgroups as mild and severe. Blood pressure (BP) of pregnant women were obtained in left-side lying position using a mercury sphygmomanometer after at least 10 minutes of rest. Ten milliliters of venous blood was taken from every pregnant women and dispensed into lithium heparin and serum was obtained. Samples were stored at ?80?°C until analyzed. Serum TSP-1 level was measured using enzyme-linked immunosorbent assay (ELISA). All tests were two-tailed and p < .05 was considered to be statistically significant.Results: TSP-1 level was significantly lower in PE group than in controls (p?=?.003). Platelet counts were similar in two groups (p = .26). TSP-1 levels were significantly lower in severe PE than in mild PE cases. According to the subgroup analysis, TSP-1 level was found significantly lower in severe preeclampsia group compared to control group (p = .015).Conclusions: In light of the association between endothelial dysfunction and preeclampsia, we claim that lower levels of TSP-1 which is released mostly from endothelial cells seem to reflect disease severity in PE. Our study reveals that maternal serum TSP-1 levels decrease in pregnant women presenting with PE and TSP-1 may be a new biomarker for the detection of PE and even severity of it. Further studies especially prospective ones with greater numbers of cases are needed. 相似文献
34.
Bernard Salame Gemaque Alex Junior Souza de Souza Manoel do Carmo Pereira Soares Andreza Pinheiro Malheiros Andrea Lima Silva Max Moreira Alves Michele Soares Gomes-Gouvêa Jo?o Renato Rebello Pinho Heriberto Ferreira de Figueiredo Djacy Barbosa Ribeiro Jonan Souza da Silva Leopoldo Augusto Moraes Ana Silvia Sardinha Ribeiro Washington Luiz Assun??o Pereira 《Emerging infectious diseases》2014,20(12):2180-2182
35.
Sixteen polymorphic microsatellite loci are described for Spergularia echinosperma, an endangered plant endemic to Central Europe. Based on 51 individuals, the number of alleles per locus ranged from 2 to 5, and the observed and expected heterozygosities were both 0.00–0.17. The markers can be valuable tool to conservation genetics of this species across its distributional range. 相似文献
36.
Khanh vinh qu?c L??ng Lan Thi Hoàng Nguy?n 《World journal of gastroenterology : WJG》2012,18(38):5338-5350
Abnormal bone metabolism and dysfunction of the calcium-parathyroid hormone-vitamin D axis have been reported in patients with viral hepatitis. Some studies suggested a relationship between vitamin D and viral hepatitis. Genetic studies have provided an opportunity to identify the proteins that link vitamin D to the pathology of viral hepatitis (i.e., the major histocompatibility complex class Ⅱ molecules, the vitamin D receptor, cytochrome P 450 , the renin-angiotensin system, apolipoprotein E, liver X receptor, toll-like receptor, and the proteins regulated by the Sp1 promoter gene). Vitamin D also exerts its effects on viral hepatitis via non-genomic factors, i.e., matrix metalloproteinase, endothelial vascular growth factor, prostaglandins, cyclooxygenase-2, and oxidative stress. In conclusion, vitamin D could have a beneficial role in viral hepatitis. Calcitriol is best used for viral hepatitis because it is the active form of the vitamin D 3 metabolite. 相似文献
37.
38.
Ibrahim Rencuzogullari Metin Cağdaş Suleyman Karakoyun Yavuz Karabağ Tufan Çınar 《The American journal of emergency medicine》2018,36(9):1722.e1-1722.e3
Venous thrombosis is recognized as one of the most important complications of nephrotic syndrome (NS). In patients with NS, venous thrombosis may develop in the renal veins, the deep veins of the lower limb, and the inferior vena cava. Here, we describe a case report of an NS patient with multiple venous thrombosis in the right renal vein, the left iliac vein, the vena cava inferior, the right atrium, and the pulmonary arteries. Moreover, we describe the successful treatment of multiple venous thrombosis with prolonged thrombolytic treatment in spite of an increased risk of bleeding due to renal biopsy. 相似文献
39.
40.
Frank?K.?Brown Farida?Kopti Charlie??Chang Scott?A.?Johnson Meir?Glick Chris?L.?Waller 《The AAPS journal》2017,19(5):1255-1263
Merck & Co., Inc., Kenilworth, NJ, USA, is undergoing a transformation in the way that it prosecutes R&D programs. Through the adoption of a “model-driven” culture, enhanced R&D productivity is anticipated, both in the form of decreased attrition at each stage of the process and by providing a rational framework for understanding and learning from the data generated along the way. This new approach focuses on the concept of a “Design Cycle” that makes use of all the data possible, internally and externally, to drive decision-making. These data can take the form of bioactivity, 3D structures, genomics, pathway, PK/PD, safety data, etc. Synthesis of high-quality data into models utilizing both well-established and cutting-edge methods has been shown to yield high confidence predictions to prioritize decision-making and efficiently reposition resources within R&D. The goal is to design an adaptive research operating plan that uses both modeled data and experiments, rather than just testing, to drive project decision-making. To support this emerging culture, an ambitious information management (IT) program has been initiated to implement a harmonized platform to facilitate the construction of cross-domain workflows to enable data-driven decision-making and the construction and validation of predictive models. These goals are achieved through depositing model-ready data, agile persona-driven access to data, a unified cross-domain predictive model lifecycle management platform, and support for flexible scientist-developed workflows that simplify data manipulation and consume model services. The end-to-end nature of the platform, in turn, not only supports but also drives the culture change by enabling scientists to apply predictive sciences throughout their work and over the lifetime of a project. This shift in mindset for both scientists and IT was driven by an early impactful demonstration of the potential benefits of the platform, in which expert-level early discovery predictive models were made available from familiar desktop tools, such as ChemDraw. This was built using a workflow-driven service-oriented architecture (SOA) on top of the rigorous registration of all underlying model entities. 相似文献