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991.
992.
Bayarchimeg Altankhishig Mohammad Ali Akbor Polan Youjing Qiu Md Riasat Hasan Takashi Saito 《Materials》2021,14(4)
The purpose of the present study was to investigate the effect of a peptide (i.e., SESDNNSSSRGDASYNSDES) derived from dentin phosphophoryn (DPP) with arginine-glycine-aspartic acid (RGD) motifs on odontoblast differentiation in vitro and to compare it with calcium hydroxide—a material used conventionally for vital pulp therapy—in terms of reparative dentin formation and pulp inflammation in vivo. Alkaline phosphatase activity assay and alizarin red S staining were performed to evaluate odontoblast-differentiation in cell culturing experiments. To observe the reparative dentin formation and pulp inflammation animal experiment was performed and examined by histological methods. The difference between the experimental group and the control group was analyzed statistically using a one-way ANOVA test. The results revealed that the DPP-derived RGD-containing peptide triggered odontoblast differentiation and mineralization in vitro. In rats undergoing direct pulp capping, the DPP-derived RGD-containing peptide was found to induce intensively formed reparative dentin with high compactness at week 4. On histological and morphometrical examinations, a smaller degree of pulpitis was observed in the specimens treated with the peptide than in those treated with calcium hydroxide. This study suggests that the DPP-derived RGD-containing peptide is a biocompatible, biodegradable and bioactive material for dentin regeneration. 相似文献
993.
A highly sensitive 1-tube nested real-time RT-PCR assay using LNA-modified primers for detection of respiratory syncytial virus 总被引:1,自引:0,他引:1
Li Zhao Ji Wang Gui-xia Li Fang-zhou Qiu Chen Chen Meng-chuan Zhao Le Wang Su-xia Duan Zhi-shan Feng Xue-jun Ma 《Diagnostic microbiology and infectious disease》2019,93(2):101-106
Respiratory syncytial virus (RSV) causes serious respiratory tract infection worldwide. The relatively low RSV load makes it difficult to detect in frail, elderly, and severely immune-compromised patients. In the present study, we developed a locked nucleic acid–-based 1-tube nested real-time RT-PCR (OTNRT-PCR) assay with the advantages of extremely high sensitivity, facile operability, and less likelihood of cross-contamination. The sensitivity, specificity, and clinical performance of the OTNRT-PCR assay were compared in parallel with a conventional TaqMan probe-based real-time PCR (qRT-PCR) assay and a traditional 2-step nested RT-PCR assay. The limit of detection of the OTNRT-PCR assay was 1.02?×?10?1 TCID50/mL, equivalent to the traditional 2-step nested RT-PCR assay and 25-fold lower than the qRT-PCR assay. Of 616 nasopharyngeal aspirates tested, 143 RSV-negative samples by qRT-PCR were confirmed as positive by sequencing the OTNRT-PCR products. We therefore conclude that OTNRT-PCR is more sensitive than qRT-PCR for detection of RSV in clinical samples. 相似文献
994.
Hua Zhang PhD Shaodong Qiu BD Fei Chen PhD Zhimin Zhu MD 《Journal of clinical ultrasound : JCU》2019,47(7):412-418
Because of better awareness and understanding of its pathophysiology, the cardiorenal syndrome (CRS) is more often diagnosed and better managed. The echocardiographic evaluation of CRS now benefits from three-dimensional speckle tracking echocardiography (3D-STE), which allows multidimensional and real-time evaluation of regional myocardial and overall cardiac function, and helps assessing the degree of myocardial damage. This article describes the application of 3D-STE in evaluating the myocardial motion in patients with CRS. 相似文献
995.
996.
Langenbacher AD Dong Y Shu X Choi J Nicoll DA Goldhaber JI Philipson KD Chen JN 《Proceedings of the National Academy of Sciences of the United States of America》2005,102(49):17699-17704
Cardiac fibrillation, a form of cardiac arrhythmia, is the most common cause of embolic stroke and death associated with heart failure. The molecular mechanisms underlying cardiac fibrillation are largely unknown. Here we report a zebrafish model for cardiac fibrillation. The hearts of zebrafish tremblor (tre) mutants exhibit chaotic movements and fail to develop synchronized contractions. Calcium imaging showed that normal calcium transients are absent in tre cardiomyocytes, and molecular cloning of the tre mutation revealed that the tre locus encodes the zebrafish cardiac-specific sodium-calcium exchanger (NCX) 1, NCX1h. Forced expression of NCX1h or other calcium-handling molecules restored synchronized heartbeats in tre mutant embryos in a dosage-dependent manner, demonstrating the critical role of calcium homeostasis in maintaining embryonic cardiac function. By creating mosaic zebrafish embryos, we showed that sporadic NCX1h-null cells were not sufficient to disrupt normal cardiac function, but clustered wild-type cardiomyocytes contract in unison in tre mutant hearts. These data signify the essential role of calcium homeostasis and NCX1h in establishing rhythmic contraction in the embryonic zebrafish heart. 相似文献
997.
HCV C基因腺病毒表达载体骨架质粒pAd.HCV-C的构建、鉴定及表达 总被引:2,自引:0,他引:2
998.
Thoracic Quantitative Dynamic MRI to Understand Developmental Changes in Normal Ventilatory Dynamics
999.
A matched, case-control study of the association between Schistosoma japonicum and liver and colon cancers, in rural China 总被引:3,自引:0,他引:3
Qiu DC Hubbard AE Zhong B Zhang Y Spear RC 《Annals of tropical medicine and parasitology》2005,99(1):47-52
A study of liver and colon cancers and their association with a previous diagnosis of schistosomiasis was performed in rural Sichuan, China. The data analysed came from 127 liver-cancer and 142 colon-cancer patients, each matched, by age, gender, hospital and township, with one or two controls. The cancer cases were identified from the hospital records of three Sichuan counties (all of which have some level of endemic schistosomiasis japonicum): Meishan (66 liver and 54 colon cases), Pujiang (16 liver and 22 colon cases) and Xichang (45 liver and 66 colon cases). Each control was selected using the hospital records for the same year the matched case of cancer was diagnosed, when the control had been found to have an illness other than cancer. Previous schistosomal infection was determined by examining the medical records at the county hospitals, searching the records at the local schistosomiasis-control stations or health-surveillance units, and, when no written record could be found, by interviews with the subjects or their relatives. Given the extremely strong association between hepatitis and liver cancer in China, only data from hepatitis-negative pairs were used in the analyses. Previous schistosomal infection was found to be significantly associated with both liver cancer (odds ratio = 3.7; 95% confidence interval = 1.0-13) and colon cancer (odds ratio = 3.3; 95% confidence interval = 1.8-6.1). The results indicate a fraction of disease attributable to schistosomiasis of 24% for colon cancer, and (among the hepatitis-negative population) one of 27% for liver cancer. 相似文献
1000.
糖尿病患者红细胞膜磷脂成分的改变 总被引:1,自引:0,他引:1
应用高效液相色谱法分析72例NIDDM患者红细胞膜磷脂成分。结果显示,NIDDM患者红细胞膜磷脂酰乙醇胺、磷脂酰肌醇、磷脂酰丝氨酸、磷脂酰胆碱、神经鞘磷脂均显著降低,而溶血磷脂酰胆碱显著增高,并且红细胞膜磷脂成分的改变与空腹血糖、糖化血红蛋白、血脂及过氧化脂质有关。提示糖尿病代谢紊乱与脂质过氧化可能是导致红细胞膜磷脂成分改变的重要因素。 相似文献