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排序方式: 共有4252条查询结果,搜索用时 31 毫秒
91.
92.
Sheung-Fat Ko Hon-Kan Yip Chen-Chang Lee Chia-Chang Lee Chia-Hao Su Chung-Cheng Huang Shu-Hang Ng Yi-Ling Chen Min-Chi Chen 《Molecular imaging and biology》2018,20(5):750-760
Purpose
This study aimed to investigate the potential of apparent diffusion coefficient (ADC) for monitoring adipose-derived mesenchymal stem cell (ADMSC) therapy of renal ischemic-reperfusion injury (IRI).Procedures
After baseline magnetic resonance imaging (MRI), 36 Sprague-Dawley rats with bilateral renal IRI were divided equally as groups 1, 2, and 3 (non-treated rats) and groups 4, 5, and 6 (ADMSC-treated rats, with 2 million ADMSCs injected via the tail vein at 6 h after IRI). Groups 1 and 4, 2 and 5, and 3 and 6 were euthanized at days 1, 3, and 7, respectively, after renal MRI. The ratios of ADC at different time points to baseline values in the cortex, outer, and inner stripes of outer medulla (OSOM/ISOM), assessments of monocyte chemoattractant protein-1 (MCP-1), CD68+ cells, tubular cast formation, and degree of fibrosis in three zones over time were compared between the non-treated and ADMSC-treated rats.Results
Among three zones, the differences in cortical ADC and immunohistochemical changes between the non-treated and ADMSC-treated IRI rats over time were less obvious. Compared with the non-treated rats, the ADMSC-treated rats exhibited significantly higher ADC ratios of OSOM and ISOM at days 1 and 3 corresponding to significantly less MCP-1 staining, CD68+ cells, and tubular casts. From day 3 to day 7, coupling with the decrement of MCP-1 and CD68+ cells in IRI kidneys, the effect of cell density on ADC declined. By day 7, the ADMSC-treated rats showed significantly higher ADC ratios of ISOM than the non-treated IRI rats, indicating better recovery, which could be related to significantly fewer tubular casts and marked amelioration of fibrosis.Conclusions
We suggest ADC is a useful in vivo biomarker for monitoring ADMSC therapy of renal IRI.93.
Realigning Demand and Supply Side Incentives to Improve Primary Health Care Seeking in Rural China 下载免费PDF全文
China's recent and ambitious health care reform involves a shift from the reliance on markets to the reaffirmation of the central role of the state in the financing and provision of services. In collaboration with the Government of the Ningxia province, we examined the impact of two key features of the reform on health care utilisation using panel household data. The first policy change was a redesign of the rural insurance benefit package, with an emphasis on reorientating incentives away from inpatient towards outpatient care. The second policy change involved a shift from a fee‐for‐service payment method to a capitation budget with pay‐for‐performance amongst primary care providers. We find that the insurance intervention, in isolation, led to a 47% increase in the use of outpatient care at village clinics and greater intensity of treatment (e.g. injections). By contrast, the two interventions in combination showed no effect on health care use over and above that generated by the redesign of the insurance benefit package. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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Karen Y. Kwok Timmy L. S. Choi Wai Him Kwok Ming Yip Lau Elvis M. K. Leung Gary N. W. Leung Jenny K. Y. Wong Terence S. M. Wan Farrington F. Adrian Anil Prabhu Emmie N. M. Ho 《Drug testing and analysis》2020,12(9):1274-1286
The use of bioactive peptides as a doping agent in both human and animal sports has become increasingly popular in recent years. As such, methods to control the misuse of bioactive peptides in equine sports have received attention. This paper describes a sensitive accurate mass method for the detection of 40 bioactive peptides and two non‐peptide growth hormone secretagogues (< 2 kDa) at low pg/mL levels in horse urine using ultra‐high performance liquid chromatography‐high resolution mass spectrometry (UHPLC/HRMS). A simple mixed‐mode cation exchange solid‐phase extraction (SPE) cartridge was employed for the extraction of 42 targets and/or their in vitro metabolites from horse urine. The final extract was analyzed using UHPLC/HRMS in positive electrospray ionization (ESI) mode under both full scan and data independent acquisition (DIA, for MS2). The estimated limits of detection (LoD) for most of the targets could reach down to 10 pg/mL in horse urine. This method was validated for qualitative detection purposes. The validation data, including method specificity, method sensitivity, extraction recovery, method precision, and matrix effect were reported. A thorough in vitro study was also performed on four gonadotrophin‐releasing factors (GnRHs), namely leuprorelin, buserelin, goserelin, and nafarelin, using the S9 fraction isolated from horse liver. The identified in vitro metabolites have been incorporated into the method for controlling the misuse of GnRHs. The applicability of this method was demonstrated by the identification of leuprorelin and one of its metabolites, Leu M4, in urine obtained after intramuscular administration of leuprorelin to a thoroughbred gelding (castrated horse). 相似文献
97.
Rahul S. Bhansali Malini Rammohan Paul Lee Anouchka P. Laurent Qiang Wen Praveen Suraneni Bon Ham Yip Yi-Chien Tsai Silvia Jenni Beat Bornhauser Aurlie Siret Corinne Fruit Alexandra Pacheco-Benichou Ethan Harris Thierry Besson Benjamin J. Thompson Young Ah Goo Nobuko Hijiya Maria Vilenchik Shai Izraeli Jean-Pierre Bourquin Sbastien Malinge John D. Crispino 《The Journal of clinical investigation》2021,131(1)
98.
Chia-Cheng Tseng Chin-Chou Wang Huang-Chih Chang Tzu-Hsien Tsai Li-Teh Chang Kuo-Tung Huang Steve Leu Chia-Hung Yen Shih-Feng Liu Chih-Hung Chen Cheng-Ta Yang Hon-Kan Yip Meng-Chih Lin 《Disease markers》2013,35(5):301-310
Background. Endothelial-derived microparticles (EDMPs) and platelet-derived microparticles (PDMPs) have been reported to be increasing in various diseases including malignant diseases. Here, we investigated whether these MPs may be useful biomarkers for predicting lung cancer (LC) disease status, cell type, or metastasis. Methods and Results. One hundred and thirty LC patients were prospectively enrolled into the study between April 2011 and February 2012. Flow cytometric analysis demonstrated that the circulating levels of platelet-derived activated MPs (PDAc-MPs), platelet-derived apoptotic MPs (PDAp-MPs), endothelial-derived activated MPs (EDAc-MPs), and endothelial-derived apoptotic MPs (EDAp-MPs) were significantly higher in LC patients than in 30 age- and gender-matched normal control subjects (all P < 0.05). Additionally, circulating level of PDAc-MPs was significantly lower (P = 0.031), whereas the circulating levels of the other three biomarkers did not differ (all P > 0.1) in early stage versus late stage LC patients. Furthermore, the circulating levels of the four types of MPs did not differ among patients with different disease statuses (i.e., disease controlled, disease progression, and disease without treatment, i.e., fresh case) (all P > 0.2) or between patients with or without LC metastasis (all P > 0.5). Moreover, only the circulating level of EDAp-MPs was significantly associated with the different cell types (i.e., squamous cell carcinoma, adenocarcinoma, and small cell carcinoma) of LC (P = 0.045). Conclusion. Circulating MP levels are significantly increased in LC patients as compared with normal subjects. Among the MPs, only an increased level of EDAp-MPs was significantly associated with different LC cell types. 相似文献
99.
100.
Ni Sann Khin Sze Huey Tan Michael LC Wang Tian Rui Siow Faye LWT Lim Fu Qiang Wang Matthew CH Ng Justina YC Lam Connie Yip 《The British journal of radiology》2021,94(1122)
Objective:Chemoradiation (CRT) may induce a change in systemic inflammatory state which could affect clinical outcomes in oesophageal cancer. We aimed to evaluate the changes and prognostic significance of systemic inflammatory markers following definitive CRT in oesophageal squamous cell carcinoma.Methods:A total of 53 patients treated with concurrent CRT were included in this retrospective analysis. We compared neutrophils, lymphocytes, platelets, neutrophil–lymphocyte ratio (NLR) and platelet–lymphocyte ratio (PLR) before and after CRT using Wilcoxon signed-rank test. Overall survival (OS) and progression-free survival (PFS) were calculated. Univariable and multivariable survival analysis were performed using Cox regression analysis. Clinical univariable survival prognostic factors with p < 0.1 were included in a multivariable cox regression analysis for backward stepwise model selection.Results:Both NLR (median ∆+2.8 [IQR −0.11, 8.62], p < 001) and PLR (median ∆+227 [81.3–523.5], p < 0.001) increased significantly after CRT. Higher levels of pre-CRT, post-CRT and change (∆) in NLR and PLR were associated with inferior OS and PFS. Post-CRT NLR (HR 1.04, 95% CI 1.02–1.07, p < 0.001), post-CRT platelets (HR 1.03, 95% CI 1.01–1.05, p = 0.005), cT-stage (HR 3.83, 95% CI 1.39–10.60, p = 0.01) and RT dose (HR 0.41, 95% CI 0.21–0.81, p = 0.01) were independent prognostic factors for OS in multivariable analysis. Change in NLR (HR 1.04, 95% CI 1.01–1.06, p = 0.001), post-CRT platelets (HR 1.03, 95% CI 1.01–1.05, p = 0.002), cT-stage (HR 3.98, 95% CI 1.55–10.25, p = 0.004) and RT dose (HR 0.41, 95% CI 0.21–0.80, p = 0.009) were independent prognostic factors for PFS.Conclusion:Both NLR and PLR increased following definitive CRT. Post-CRT NLR and ∆NLR were associated with adverse survival in oesophageal SCC.Advances in knowledge:We showed that CRT increased PLR and NLR, possibly reflecting a systemic inflammatory state which were associated with poor clinical outcomes in oesophageal SCC. 相似文献