检索结果-南通市图书馆

image Reconstructions from Limit Views and Angle Coverage Data for a Stationary Multi-Pinhole SPECT System

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Tsinghua Science and Technology 2010年第1期15卷 44-49页

作者： HSIEH Hohui HSIAO Ingtsung Department of Medical Imaging and Radiological Sciences Chang Gung UniversityTaoyuan 333 molecular Imaging center Chang Gung Memorial HospitalTaoyuan 333

The goal of this paper is to investigate different reconstruction methods for solving the limited angle problem in reconstructing the projection data from a stationary multi-pinhole system based on a three-head clinical single photon emission computed tomography （SPECT） camera. Three iterative recon- struction approaches were studied including maximum likelihood expectation maximization （MLEM）, maximum a posteriori expectation maximization （MAPEM） with a smoothing prior, and an alternating optimization schemes from MLEM and total variation （TV） optimization. A three-headed multipinhole SPECT was simulated with apertures of nine 1-mm pinholes each, and covered scanning volume of 6-mm diameter. The reconstructions were optimized for various iterations based on visual inspections, and finally 20 iterations were applied for each method. For both MLEM-TV and MAPEM-TV, various initial reconstructions before TV optimization were studied. The smoothing parameter for MAPEM and the gradient descent constant for TV were also investigated through visual comparison. The preliminary results showed the 3 reconstruction methods generated compatible images, and can restore the images from projection data suffering limited angular sampling. However, MLEM was noisy for low-count and highly limited angle data, and thus suitable smoothing in MAPEM alleviated this problem, initial reconstructions were necessary for better edge enhancement in TV. The conclusion is that TV might be potential in producing more edge-enhanced images if all parameters were optimized.

关键词： multipinhole single photon emission computed tomography (SPECT) iterative reconstruction total variation (TV) optimization

Glycerophospholipids pathways and chromosomal instability in gastric cancer: Global lipidomics analysis

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastrointestinal Oncology 2019年第3期11卷 181-194页

作者： Cheng-Yu Hung Ta-Sen Yeh Cheng-Kun Tsai Ren-Chin Wu Ying-Chieh Lai Meng-Han Chiang Kuan-Ying Lu Chia-Ni Lin Mei-Ling Cheng Gigin Lin molecular Medicine Research center Chang Gung University Clinical Metabolomics Core Lab Chang Gung Memorial Hospital at Linkou and Chang Gung University Department of Medical Imaging and Intervention Imaging Core Lab Institute for Radiological Research Chang Gung Memorial Hospital at Linkou and Chang Gung University Department of Surgery Chang Gung Memorial Hospital at Linkou and Chang Gung University Department of Pathology Chang Gung Memorial Hospital at Linkou and Chang Gung University Department of Laboratory Medicine Chang Gung Memorial Hospital at Linkou and Chang Gung University Department of Biomedical Science College of Medicine Chang Gung University

BACKGROUND Based on the breakthrough of genomics analysis, The Cancer Genome Atlas Research Group recently proposed an integrative genomic analysis, dividing gastric cancer(GC) into four subtypes, characterized by the chromosomal instability(CIN) status. However, the CIN status of GC is still vaguely characterized and lacking the valuable easy-to-use CIN markers to diagnosis in molecular and histological *** To explore the associations of CIN with downstream lipidomics *** We collected cancerous and noncancerous tissue samples from 18 patients with GC; the samples were divided into CIN and non-CIN types based on the system of The Cancer Genome Atlas Research Group and 409 sequenced oncogenes and tumor suppressor genes. We identified the lipidomics profiles of the GC samples and samples of their adjacent noncancerous tissues by using liquid chromatography–mass spectrometry. Furthermore, we selected leading metabolites based on variable importance in projection scores of > 1.0 and P <*** Twelve men and six women participated in this study; the participants had a median age of 67.5 years(range, 52–87 years) and were divided into CIN(n = 9)and non-CIN(n = 9) groups. The GC samples exhibited distinct profiles of lysophosphocholine, phosphocholine, phosphatidylethanolamine,phosphatidylinositol, phosphoserine, sphingomyelin, ceramide, and triglycerides compared with their adjacent noncancerous tissues. The glycerophospholipid levels(phosphocholine, phosphatidylethanolamine, and phosphatidylinositol)were 1.4-to 2.3-times higher in the CIN group compared with the non-CIN group(P < 0.05). Alterations in the glycerolipid and glycerophospholipid pathways indicated progression of GC toward *** The lipidomics profiles of GC samples were distinct from those of their adjacent noncancerous tissues. CIN status of GC is primarily associated with downstream lipidomics in the glycerophospholipid pathway.

关键词： Chromosomal instability Gastric cancer Glycerophospholipids Metabolomics Lipidomics profile

MULTIPLICITY OF POSITIVE SOLUTIONS FOR SINGULAR ELLIPTIC SYSTEMS WITH CRITICAL SOBOLEV-HARDY AND CONCAVE EXPONENTS

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Mathematica Scientia 2011年第3期31卷 791-804页

作者： Tsing-San Hsu Huei-Lin Li center for General Education chang gung University

In this paper,we consider a singular elliptic system with both concave non-linearities and critical Sobolev-Hardy growth terms in bounded *** means of variational methods,the multiplicity of positive solutions to this... 详细信息

关键词： elliptic system critical Sobolev-Hardy exponent concave exponents Nehari manifold

MULTIPLE POSITIVE SOLUTIONS FOR QUASILINEAR ELLIPTIC PROBLEMS INVOLVING CONCAVE-CONVEX NONLINEARITIES AND MULTIPLE HARDY-TYPE TERMS

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Scientia 2013年第5期33卷 1314-1328页

作者： Tsing-San HSU center for General Education Chang Gung University

In this paper, we deal with the existence and multiplicity of positive solutions for the quasilinear elliptic problem -△pu-∑i=1^kμi｜u｜^p-2/｜x-ai｜p^u=｜u｜^p^＊-2u＋λ｜u｜^q-2u,x∈Ω,where Ω belong to R^N（N ≥ 3） is a smooth bounded domain such that the different points ai∈Ω,i= 1,2,...,k,0≤μi〈μ^-=（N-p/p）^p,λ〉0,1≤q〈p,and p^＊=p^N/*** results depend crucially cn the parameters λ,q and μi for i=1,2,...,k.

关键词： multiple positive solutions concave-convex nonlinearities multiple Hardy- type terms

Manganese antagonizes iron blocking mitochondrial aconitase expression in human prostate carcinoma cells

在线全文

学校读者我要写书评

暂无评论

Asian Journal of Andrology 2006年第3期8卷 307-315,387页

作者： Ke-Hung Tsui Phei-Lang chang Horng-Heng Juang Department of Urology Chang Gung Molecular Image CenterChang Gung Memorial Hospital Department of Urology Chang Gung Memorial Hospital chang gung molecular image center Chang Gung Memorial Hospital Department of AnatomyChang Gung UniversityKwei-Shan.Tao-Yuan 333TaiwanChina

Aim:To investigate the possible role of manganese in the regulation of mitochondrial aconitase(mACON)activity human prostate carcinoma cell line PC-3 ***:The mACON enzymatic activities of human prostate carcinoma cell line PC-3 cells were determined using a reduced nicotinamide adenine dmucleotide-coupled assay. Immunoblot and transient gene expression assays were used to study gene expression of the *** putative response element for gene expression was identified using reporter assays with site-directed mutagenesis and electro- phoretic mobility-shift ***:In vitro study revealed that manganese chloride(MnCl2)treatment for 16h inhibited the enzymatic activity of mACON,which induced the inhibition of citrate utility and cell proliferation of PC- 3 *** results from transient gene expression assays showed that MnCl_2,treatment upregulated gene translation by approximately 5-fold through the iron response element pathway,immunoblot and reporter assays showed that MnCl_2 treatments inhibited protein and gene expression of *** effect was reversed by co- treatment with fenic ammonium *** reporter assays with site-directed mutagenesis and electrophoretic mobility-shift assays suggested that a putative metal response element in the promoter of the mACON gene was involved in the regulation of MnCl_2 on the gene expression of ***:These findings suggest that manganese acts as an antagonist of iron,disrupting the enzymatic activity and gene expression of mACON and citrate metabolism in the prostate.

关键词： citrate adenosine triphosphate proliferation PC-3 metal response element prostate carcinoma cell line

Coagulation factor Ⅶ gene polymorphisms are not associated with the occurrence or the survival of hepatocellular carcinoma:a report of 37 cases

在线全文

学校读者我要写书评

暂无评论

Cancer Biology & Medicine 2018年第3期15卷 275-281页

作者： Chih-Che Lin Chun-Hsien Wu Li-Yu Chen Ming-Chao Tsai Ahmed M.Elsarawy Kuang-Tzu Huang Liver Transplantation center Department of Surgery Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine Institute for Translational Research in Biomedicine Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine Division of Hepato-Gastroenterology Department of Internal Medicine Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine

Objective: Coagulation factor VII(FVII) triggers the extrinsic pathway of blood coagulation. In our previous study, we showed that FVII plays an important role in tumorigenesis of hepatocellular carcinoma(HCC). However, the role of FVII polymorphism in HCC is still unknown. The present study aimed to investigate the relationship between HCC carcinogenesis and single nucleotide polymorphism of ***: Thirty-seven HCC patients and 30 healthy donors were recruited in this study. Four common FVII gene polymorphisms– a decanucleotide insertion at position –323(–323 ins10-bp), a G to T substitution at position –401(–401 G/T), a G to A substitution at position –402(–402 G/A), and a T to C substitution at position –122(–122 T/C) – were analyzed by sequencing or commercialized assays using genomic DNA isolated from blood samples. Clinicopathological parameters between control and HCC subjects were compared according to the specific ***: The most common nucleotide variation was –402 G/A. However, no statistically significant difference was observed between healthy controls and HCC subjects for all four polymorphisms in terms of genotype distribution and allele frequencies,indicating that these polymorphisms may not affect HCC tumorigenesis. Furthermore, no association was found between–402 G/A polymorphisms and tumor stage, recurrence, and overall ***: Our results indicate that FVII polymorphisms may not be a key factor that clinically impact tumorigenesis and outcomes of HCC, although further investigations should be conducted to confirm our findings.

关键词： Factor Ⅶ gene polymorphism liver hepatocellular cancer survival

Pancreatic stent improves the success rate of needle-knife papillotomy in patients with difficult biliary cannulation

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2025年第1期31卷 58-67页

作者： Mu-Hsien Lee Cheng-Hui Lin Chi-Huan Wu Yung-Kuan Tsou Kai-Feng Sung Sheng-Fu Wang Nai-Jen Liu Department of Gastroenterology and Hepatology Chang Gung Memorial Hospital and Chang Gung University College of MedicineTaoyuan 33305Taiwan School of Medicine Chang Gung UniversityTaoyuan 33305Taiwan

BACKGROUND Needle-knife precut papillotomy(NKP)is typically performed ***,it remains unclear whether pancreatic stent(PS)placement can improve the outcomes of *** To explore whether PS placement improves the success rate of NKP in patients with difficult biliary *** This single-center retrospective study included 190 patients who underwent NKP between January 2017 and December 2021 after failed conventional biliary *** cases with incidental pancreatic duct cannulation during conventional biliary cannulation,the decision for pre-NKP PS placement was made at the endoscopist's *** primary outcome was the difference in the NKP success rate between patients with and without PS placement;the secondary outcome was the adverse event *** Among the 190 participants,82 received pre-NKP PS(PS-NKP group)whereas 108 did not[freehand or freehand NKP(FH-NKP)group].Post-NKP selective biliary cannulation was successful in 167(87.9%)patients,and the PS-NKP had a significantly higher success rate than the FH-NKP group(93.9%vs 83.3%,P=0.027).The overall adverse event rates were 7.3%and 11.1%in the PS-NKP and FH-NKP groups,respectively(P=0.493).A periampullary diverticulum(PAD)and significant intraoperative bleeding during NKP were independently associated with NKP failure;however,a pre-NKP PS was the only predictor of NKP *** the 44 participants with PADs,the PS-NKP group had a non-significantly higher NKP success rate than the FH-NKP group(87.5%and 65%,respectively;P=0.076).CONCLUSION PS significantly improved the success rate of NKP in patients with difficult biliary cannulation.

关键词： Difficult biliary cannulation Endoscopic retrograde cholangiopancreatography Needle-knife papillotomy Pancreatic stent Selective biliary cannulation

Platelet-rich plasma enhances adipose-derived stem cell-mediated angiogenesis in a mouse ischemic hindlimb model

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Stem Cells 2018年第12期10卷 212-227页

作者： Chia-Fang Chen Han-Tsung Liao Department of Plastic and Reconstructive Surgery Chang Gung Memorial Hospital Craniofacial Research center Chang Gung Memorial Hospital College of Medicine Chang Gung University

AIM To evaluate the angiogenic effect of platelet-rich plasma(PRP)-preconditioned adipose-derived stem cells(ADSCs) both in vitro and in a mouse ischemic hindlimb *** ADSCs were divided based on culture medium: 2.5% PRP, 5% PRP, 7.5% PRP, and 10% PRP. Cell proliferation rate was analyzed using the MTS assay. The gene expression of CD31, vascular endothelial growth factor, hypoxia-inducible factors, and endothelial cell nitric oxide synthase was analyzed using reverse transcription polymerase chain reaction. Cell markers and structural changes were assessed through immunofluorescence staining and the tube formation assay. Subsequently, we studied the in vivo angiogenic capabilities of ADSCs by a mouse ischemic hindlimb *** The proliferation rate of ADSCs was higher in the 2.5%, 5%, and 7.5% PRP groups. The expression of hypoxia-inducible factor, CD31, vascular endothelial growth factor, and endothelial cell nitric oxide synthase in the 5% and 7.5% PRP groups increased. The 5%, 7.5%, and 10% PRP groups showed higher abilities to promote both CD31 and vascular endothelial growth factor production and tubular structure formation in ADSCs. According to laser Doppler perfusion scan, the perfusion ratios of ischemic limb to normal limb were significantly higher in 5% PRP, 7.5% PRP, and human umbilical vein endothelial cells groups compared with the negative control and fetal bovine serum(FBS) groups(0.88 ± 0.08, 0.85 ± 0.07 and 0.81 ± 0.06 for 5%, 7.5% PRP and human umbilical vein endothelial cells compared with 0.42 ± 0.17 and 0.54 ± 0.14 for the negative control and FBS, P < 0.01).CONCLUSION PRP-preconditioned ADSCs presented endothelial cell characteristics in vitro and significantly improved neovascularization in ischemic hindlimbs. The optimal angiogenic effect occurred in 5% PRP-and 7.5% PRPpreconditioned ADSCs.

关键词： Platelet-rich plasma Adipose-derived stem cells Mesenchymal stem cell Angiogenesis Endothelial differentiation Mouse ischemic hindlimb model

Prenatal glucocorticoid contributed to rat lung dysplasia is related to asymmetric dimethylarginine/nitric oxide pathway

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science Bulletin 2015年第16期60卷 1416-1425页

作者： Yu-Chieh Chen Li-Tung Huang You-Lin Tain Chih-Cheng Chen Jiunn-Ming Sheen Mao-Meng Tiao Chih-Min Tsai Ho-chang Kuo Chao-Cheng Huang Kow-Aung changDepartment of Anesthesiology chang gung Memorial Hospital-Kaohsiung Medical center Graduate Institute of Clinical Medical Science chang gung University College of Medicine Hong-Ren Yu Department of Pediatrics Chang Gung Memorial Hospital-Kaohsiung Medical Center Graduate Institute of Clinical Medical Science Chang Gung University College of Medicine Department of Pathology Chang Gung Memorial Hospital-Kaohsiung Medical Center Graduate Institute of Clinical Medical Science Chang Gung University College of Medicine

Prenatal glucocorticoids （GCs） have been used to induce maturation of preterm fetal lungs and prevent the development of respiratory distress syndrome of the premature. Pulmonary surfactant induction has been regarded as the most important effect of prenatal GCs. However, report about the prolonged effects of prenatal GCs on the development of rat lung is of limited. In this study, we tried to investigate the acute and chronic modulation effects of prenatal dexamethasone （DEX） to asymmetric dimethylarginine （ADMA）/nitric oxide （NO） signal pathway of lung tissue. Pregnant Sprague Dawley rats at gestational day 14-20 were administered i.p. DEX （0.1 mg· kg-1 ·d-1）. Acute programming effects of prenatal DEX were assessed at postnatal day 7, and long-term programming effects of offspring were assessed at day 120. We found that repetitive prenatal DEX exposure contributes to DNA oxidative damage and alveolar tissue dysplasia. Prenatal DEX treatment decreased ADMA and increased iNOS expres- sion. Prenatal DEX treatment also increased TNF-α transcript expression and decreased HDAC2 protein expression at acute stage. In conclusion, repetitive prenatal DEX has prolonged stress damage effects on lung tissue.

关键词： Prenatal glucocorticoids ADMA DNA oxidative damage TNF-α HDAC2 Lung dysplasia