Jan-kan Chen - Academia.edu (original) (raw)
Papers by Jan-kan Chen
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Plastic and Reconstructive Surgery, 1999
... Craniofacial Abnormalities. Chang, Sophia CNMD; Liao, Yu-Fang DDS; Hung, Li-Man MS; Tseng, Ch... more ... Craniofacial Abnormalities. Chang, Sophia CNMD; Liao, Yu-Fang DDS; Hung, Li-Man MS; Tseng, Ching-Shiow Ph.D.; Hsu, Jung-Hsiang MS; Chen, Jan-Kan Ph.D. Article Outline. Collapse Box Author Information. Tao-Yuan, Taiwan. ...
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Drug Development Research, 2001
... in 50 mM KH2PO4/K2HPO4 buffer (pH 7.4) containing K2H2-EDTA (0.3 mM), NBT (0.6 mM), xanthine ... more ... in 50 mM KH2PO4/K2HPO4 buffer (pH 7.4) containing K2H2-EDTA (0.3 mM), NBT (0.6 mM), xanthine (0.1 mM), and xan-thine oxidase ... The severity of reperfusion-induced arrhythmias is critically dependent on the duration of the proceeding period of ischemia [Manning et al ...
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The effects of retinoli- acid on the epidermal growth factor (EGF) receptor binding and cell grow... more The effects of retinoli- acid on the epidermal growth factor (EGF) receptor binding and cell growth of normal and simian virus 40 (SV40)- transformed BALB/c 3T3 cells were compared under identical culture conditions. Retinoic acid induced a rapid enhancement of EGF binding to SV40-transformed cells. Half-maximal enhancement occurred at about 7 h after the cells were exposed to 20 ng/ml
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Molecular Therapy — Methods & Clinical Development, 2015
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International journal of pharmaceutics, Jan 7, 2007
Osteomyelitis has been one of the most common causes of post-operative problems and complications... more Osteomyelitis has been one of the most common causes of post-operative problems and complications despite the advances in surgical techniques and the availability of newly developed antibiotics. Local antibiotic and growth factor delivery devices for treatment of various surgical infections have been studied recently, especially in the case of orthopedic infections. The report was to develop novel solvent-free biodegradable capsules for antibiotics and growth factors delivery. To fabricate a biodegradable capsule, polylactide-polyglycolide copolymers were pre-mixed with vancomycin. The mixture was then compression molded and sintered to form a cylinder with a cover of 8 mm in diameter. After the addition of 1 and 10 microg recombinant bone morphogenetic protein (rhBMP-2) into the core, an ultrasonic welder was used to seal the capsules. An elution method was employed to characterize the in vitro release characteristics of the antibiotics and the rhBMP-2 over a 30-day period. The HPL...
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Life sciences, Jan 7, 2000
This study investigates how chronic exercise affects Ox-LDL mediated-platelet activation. Five-we... more This study investigates how chronic exercise affects Ox-LDL mediated-platelet activation. Five-week-old male Wistar rats were assigned to either control or trained groups. Trained rats were treadmill-trained for 10 weeks after familiarization. The following measurements were taken in both control and trained groups: plasma lipid profile, oxidation of LDL, platelet adhesiveness, aggregability, cGMP contents, plasma and platelet-NO metabolite (nitrite plus nitrate) levels, and urinary 8-iso-prostaglandin F2alpha (8-iso-PG F2alpha) levels. Based on those measurements, major findings in this study can be summarized as follows: 1) the trained group prolonged the lag time of isolated LDL subjected to copper-induced in vitro oxidation significantly longer than the control group; 2) although having higher plasma and platelet derived-NO metabolite levels, the trained group had lower urinary excretion of 8-iso-PGF2alpha than the control group; 3) the trained group had a lower platelet adhesiv...
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Investigative ophthalmology & visual science, 1994
To study the effects of collagen matrix and fibroblasts on the growth and development of human bu... more To study the effects of collagen matrix and fibroblasts on the growth and development of human bulbar conjunctival epithelial cells. Human bulbar conjunctival epithelial cells were cultured on three-dimensional collagen gels containing either normal human conjunctival fibroblasts (HCF), Swiss 3T3 cells, or no cells. After 1 week of culturing, half of the cultures were raised to the air-liquid interface and the rest of the cultures remained submerged. On day 14, cultures were fixed and sectioned for light and electron microscopic studies. Conjunctival epithelial cells cultured on fibroblast-contracted collagen lattice developed into a multicell-layer epithelium with characteristic epithelial structural features including microvilli, desmosomes, early hemidesmosomes, and basement membrane-like structures. Formation of all or some of the above features appeared to be influenced by the type of fibroblasts in the collagen lattices. Structures such as hemidesmosomes and basement membrane ...
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Cancer research, Jan 15, 1988
Both acquired and natural resistance to chemotherapy agents have proved problematic in the treatm... more Both acquired and natural resistance to chemotherapy agents have proved problematic in the treatment of neoplasia. Thymidylate synthase, which catalyzes the synthesis of thymidine precursors, has been shown to be amplified in response to a variety of chemotherapeutic agents. The detection of such amplification could prove beneficial in the development of alternative clinical protocols. In this study we report the use of existing enzymatic amplification methods in order to detect incipient amplification of the thymidylate synthase gene upon resistance to cisplatin. The assay utilizes a modification of the polymerase chain reaction in which a sequence of the thymidylate synthase gene is amplified including two flanking oligonucleotides acting as primers for DNA synthesis. This method exhibits greater sensitivity than conventional nucleic acid detection methods and requires less than 100 ng of total RNA from patient tumors and no in vitro culturing of patient cells.
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FASEB journal : official publication of the Federation of American Societies for Experimental Biology, 1988
Heparin-binding growth factors (HBGF) are essential and key mitogens for human adult large vessel... more Heparin-binding growth factors (HBGF) are essential and key mitogens for human adult large vessel endothelial cells. At 170 pg/ml, the tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA) caused a 50% inhibition of heparin-binding growth factor type one (HBGF-1)-stimulated DNA synthesis in human adult large vessel endothelial cells. TPA at 1 ng/ml completely inhibited HBGF-1-stimulated proliferation. TPA at 5 ng/ml reduced specific HBGF-1 receptor sites from 6600 per cell to 3200 per cell without affecting receptor affinity. Since phorbol esters are potent activators of protein kinase C, desensitizes both animal capillary and human adult large vessel endothelial cells to the mitogenic effects of HBGF by down-regulation of specific HBGF receptors.--HOSHI, H; KAN, M.; MIOH, H.; CHEN J.-K.; McKEEHAN, W. L. Phorbol ester reduces number of heparin-binding growth factor receptors in human adult endothelial cells.
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Ophthalmic Research, 2003
Purpose: To study the expression of TIMP-4 in cultured corneal cells and in corneal neovasculariz... more Purpose: To study the expression of TIMP-4 in cultured corneal cells and in corneal neovascularization. Methods: Human limbo-corneal epithelial cells, fibroblasts, and endothelial cells were cultured in serum-free, PMA- or basic fibroblast growth factor (bFGF)-treated condition. Neovascularization in rat cornea was induced by suturing. The expression of TIMP-4 was examined by immunohistochemistry, Western blot and RT-PCR. Results: TIMP-4 was constitutively
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in Vitro Cellular & Developmental Biology-plant - IN VITRO CELL DEV BIOL-PLANT, 1989
Summary Stimulation of human arterial endothelial cells with heparin-binding growth factor-1 (HB... more Summary Stimulation of human arterial endothelial cells with heparin-binding growth factor-1 (HBGF-1) resulted in a 40% to 60% increase in the cellular adenylate cyclase activity and intracellular cAMP content. The stimulatory effect of HBGF-1 was effectively suppressed by pretreating the cells with transforming growth factor-β (TGF-β), an endothelial cell growth inhibitor. The inhibition of the adenylate cyclase activity precedes growth inhibition by at least 24 h. The half maximal inhibitory dose was calculated to be 0.2 ng/ml for the inhibition of both cyclase activity and cell growth. The possible role of the adenylate cyclase suppression in growth inhibition by TGF-β is discussed.
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Progress in Retinal and Eye Research, 2006
Corneal angiogenesis is associated with a variety of corneal diseases, and is sometimes vision th... more Corneal angiogenesis is associated with a variety of corneal diseases, and is sometimes vision threatening. In recent years, with the discovery of major pro- and anti-angiogenic factors in the cornea, details of the angiogenic process are gradually unveiled. Of note, corneal inflammation and neovascularization associated with severe limbal stem cell (LSC) deficiency is a clinically challenging issue in that the condition persists long after the initial insult, and will not improve without transplantation of LSCs. However, to date the molecular mechanism by which LSC transplantation restores corneal avascularity is not fully understood. In addition to discussing major pro-angiogenic factors involved in corneal neovascularization, this review article also focuses on possible molecular mechanisms underlying persistent inflammation and neovascularization following severe LSC deficiency, and anti-angiogenic factors expressed by human limbo-corneal epithelial cells (HLCECs). Most of the recently discovered corneal anti-angiogenic factors belong to extracellular matrix proteins that acquire angio-inhibitory activity only after proper proteolytic processing. Our recent findings showed that the secretion of endostatin (derived from basement membrane collagen XVIII) and restin (from collagen XV) by HLCECs were enhanced when HLCECs were cultivated on amniotic membrane (AM). This adds to the advantage of transplanting ex vivo expanded HLCECs cultivated on AM in that the anti-angiogenic activity of the epithelial cells is augmented in a physiological way. Furthermore, proteomic profiling of HLCECs and human conjunctival epithelial cells (HCECs) identified a 14-3-3 protein (stratifin) preferentially expressed by HLCECs. In addition to functioning as a cell cycle controller, keratinocyte-derived stratifin induces MMPs which are involved in the generation of restin (by MMP-1) and endostatin (by MMP-3). These findings highlight the significance of delicate epithelial-matrix interactions in the maintenance of corneal avascularity.
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Proceedings of the National Academy of Sciences, 1987
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Life Sciences, 1994
Binding experiments were performed with [3H]ouabain on cultured human umbilical vein endothelial ... more Binding experiments were performed with [3H]ouabain on cultured human umbilical vein endothelial cells (huvEC). Saturation studies yielded a binding capacity (Bmax) of 820 +/- 81 fmole/mg pr.(n = 4) and dissociation constant (KD) of 11.7 +/- 2.1nM (n = 4) in K(+)-free buffer for specific [3H] ouabain binding on these cells. External K+ inhibited this binding in a dose-dependent manner. The mean value of Bmax is equivalent to about 4 x 10(5) sites per cell, comparable with that of smooth muscle cell. These data demonstrated the presence of specific [3H]ouabain binding linked to Na+/K+ pump, consistent with the observations of ouabain-sensitive 86Rb uptake in huvEC. Effect of cholesterol enrichment was also studied. Incubation in media supplemented with cholesterol-phospholipid liposomes of molar ratio of 2:1 for 18 hours reduced the Bmax by 31% (P < 0.05) without significantly changed the value of KD. This reduction of [3H]ouabain binding appeared to be specific for cholesterol since liposome made with pure phospholipid did not alter binding. Recent findings indicate that cholesterol-enrichment and plasma lipoproteins enhance vascular contractile response, our results suggest that the cholesterol-enrichment of endothelial cells may also indirectly affect the vascular response via disturbing the function of Na+/K+ pump.
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Life Sciences, 1997
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Life Sciences, 1997
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Life Sciences, 1999
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Journal of Surgical Research, 2004
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Plastic and Reconstructive Surgery, 1999
... Craniofacial Abnormalities. Chang, Sophia CNMD; Liao, Yu-Fang DDS; Hung, Li-Man MS; Tseng, Ch... more ... Craniofacial Abnormalities. Chang, Sophia CNMD; Liao, Yu-Fang DDS; Hung, Li-Man MS; Tseng, Ching-Shiow Ph.D.; Hsu, Jung-Hsiang MS; Chen, Jan-Kan Ph.D. Article Outline. Collapse Box Author Information. Tao-Yuan, Taiwan. ...
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Drug Development Research, 2001
... in 50 mM KH2PO4/K2HPO4 buffer (pH 7.4) containing K2H2-EDTA (0.3 mM), NBT (0.6 mM), xanthine ... more ... in 50 mM KH2PO4/K2HPO4 buffer (pH 7.4) containing K2H2-EDTA (0.3 mM), NBT (0.6 mM), xanthine (0.1 mM), and xan-thine oxidase ... The severity of reperfusion-induced arrhythmias is critically dependent on the duration of the proceeding period of ischemia [Manning et al ...
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The effects of retinoli- acid on the epidermal growth factor (EGF) receptor binding and cell grow... more The effects of retinoli- acid on the epidermal growth factor (EGF) receptor binding and cell growth of normal and simian virus 40 (SV40)- transformed BALB/c 3T3 cells were compared under identical culture conditions. Retinoic acid induced a rapid enhancement of EGF binding to SV40-transformed cells. Half-maximal enhancement occurred at about 7 h after the cells were exposed to 20 ng/ml
Bookmarks Related papers MentionsView impact
Molecular Therapy — Methods & Clinical Development, 2015
Bookmarks Related papers MentionsView impact
International journal of pharmaceutics, Jan 7, 2007
Osteomyelitis has been one of the most common causes of post-operative problems and complications... more Osteomyelitis has been one of the most common causes of post-operative problems and complications despite the advances in surgical techniques and the availability of newly developed antibiotics. Local antibiotic and growth factor delivery devices for treatment of various surgical infections have been studied recently, especially in the case of orthopedic infections. The report was to develop novel solvent-free biodegradable capsules for antibiotics and growth factors delivery. To fabricate a biodegradable capsule, polylactide-polyglycolide copolymers were pre-mixed with vancomycin. The mixture was then compression molded and sintered to form a cylinder with a cover of 8 mm in diameter. After the addition of 1 and 10 microg recombinant bone morphogenetic protein (rhBMP-2) into the core, an ultrasonic welder was used to seal the capsules. An elution method was employed to characterize the in vitro release characteristics of the antibiotics and the rhBMP-2 over a 30-day period. The HPL...
Bookmarks Related papers MentionsView impact
Life sciences, Jan 7, 2000
This study investigates how chronic exercise affects Ox-LDL mediated-platelet activation. Five-we... more This study investigates how chronic exercise affects Ox-LDL mediated-platelet activation. Five-week-old male Wistar rats were assigned to either control or trained groups. Trained rats were treadmill-trained for 10 weeks after familiarization. The following measurements were taken in both control and trained groups: plasma lipid profile, oxidation of LDL, platelet adhesiveness, aggregability, cGMP contents, plasma and platelet-NO metabolite (nitrite plus nitrate) levels, and urinary 8-iso-prostaglandin F2alpha (8-iso-PG F2alpha) levels. Based on those measurements, major findings in this study can be summarized as follows: 1) the trained group prolonged the lag time of isolated LDL subjected to copper-induced in vitro oxidation significantly longer than the control group; 2) although having higher plasma and platelet derived-NO metabolite levels, the trained group had lower urinary excretion of 8-iso-PGF2alpha than the control group; 3) the trained group had a lower platelet adhesiv...
Bookmarks Related papers MentionsView impact
Investigative ophthalmology & visual science, 1994
To study the effects of collagen matrix and fibroblasts on the growth and development of human bu... more To study the effects of collagen matrix and fibroblasts on the growth and development of human bulbar conjunctival epithelial cells. Human bulbar conjunctival epithelial cells were cultured on three-dimensional collagen gels containing either normal human conjunctival fibroblasts (HCF), Swiss 3T3 cells, or no cells. After 1 week of culturing, half of the cultures were raised to the air-liquid interface and the rest of the cultures remained submerged. On day 14, cultures were fixed and sectioned for light and electron microscopic studies. Conjunctival epithelial cells cultured on fibroblast-contracted collagen lattice developed into a multicell-layer epithelium with characteristic epithelial structural features including microvilli, desmosomes, early hemidesmosomes, and basement membrane-like structures. Formation of all or some of the above features appeared to be influenced by the type of fibroblasts in the collagen lattices. Structures such as hemidesmosomes and basement membrane ...
Bookmarks Related papers MentionsView impact
Cancer research, Jan 15, 1988
Both acquired and natural resistance to chemotherapy agents have proved problematic in the treatm... more Both acquired and natural resistance to chemotherapy agents have proved problematic in the treatment of neoplasia. Thymidylate synthase, which catalyzes the synthesis of thymidine precursors, has been shown to be amplified in response to a variety of chemotherapeutic agents. The detection of such amplification could prove beneficial in the development of alternative clinical protocols. In this study we report the use of existing enzymatic amplification methods in order to detect incipient amplification of the thymidylate synthase gene upon resistance to cisplatin. The assay utilizes a modification of the polymerase chain reaction in which a sequence of the thymidylate synthase gene is amplified including two flanking oligonucleotides acting as primers for DNA synthesis. This method exhibits greater sensitivity than conventional nucleic acid detection methods and requires less than 100 ng of total RNA from patient tumors and no in vitro culturing of patient cells.
Bookmarks Related papers MentionsView impact
FASEB journal : official publication of the Federation of American Societies for Experimental Biology, 1988
Heparin-binding growth factors (HBGF) are essential and key mitogens for human adult large vessel... more Heparin-binding growth factors (HBGF) are essential and key mitogens for human adult large vessel endothelial cells. At 170 pg/ml, the tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA) caused a 50% inhibition of heparin-binding growth factor type one (HBGF-1)-stimulated DNA synthesis in human adult large vessel endothelial cells. TPA at 1 ng/ml completely inhibited HBGF-1-stimulated proliferation. TPA at 5 ng/ml reduced specific HBGF-1 receptor sites from 6600 per cell to 3200 per cell without affecting receptor affinity. Since phorbol esters are potent activators of protein kinase C, desensitizes both animal capillary and human adult large vessel endothelial cells to the mitogenic effects of HBGF by down-regulation of specific HBGF receptors.--HOSHI, H; KAN, M.; MIOH, H.; CHEN J.-K.; McKEEHAN, W. L. Phorbol ester reduces number of heparin-binding growth factor receptors in human adult endothelial cells.
Bookmarks Related papers MentionsView impact
Ophthalmic Research, 2003
Purpose: To study the expression of TIMP-4 in cultured corneal cells and in corneal neovasculariz... more Purpose: To study the expression of TIMP-4 in cultured corneal cells and in corneal neovascularization. Methods: Human limbo-corneal epithelial cells, fibroblasts, and endothelial cells were cultured in serum-free, PMA- or basic fibroblast growth factor (bFGF)-treated condition. Neovascularization in rat cornea was induced by suturing. The expression of TIMP-4 was examined by immunohistochemistry, Western blot and RT-PCR. Results: TIMP-4 was constitutively
Bookmarks Related papers MentionsView impact
Bookmarks Related papers MentionsView impact
in Vitro Cellular & Developmental Biology-plant - IN VITRO CELL DEV BIOL-PLANT, 1989
Summary Stimulation of human arterial endothelial cells with heparin-binding growth factor-1 (HB... more Summary Stimulation of human arterial endothelial cells with heparin-binding growth factor-1 (HBGF-1) resulted in a 40% to 60% increase in the cellular adenylate cyclase activity and intracellular cAMP content. The stimulatory effect of HBGF-1 was effectively suppressed by pretreating the cells with transforming growth factor-β (TGF-β), an endothelial cell growth inhibitor. The inhibition of the adenylate cyclase activity precedes growth inhibition by at least 24 h. The half maximal inhibitory dose was calculated to be 0.2 ng/ml for the inhibition of both cyclase activity and cell growth. The possible role of the adenylate cyclase suppression in growth inhibition by TGF-β is discussed.
Bookmarks Related papers MentionsView impact
Progress in Retinal and Eye Research, 2006
Corneal angiogenesis is associated with a variety of corneal diseases, and is sometimes vision th... more Corneal angiogenesis is associated with a variety of corneal diseases, and is sometimes vision threatening. In recent years, with the discovery of major pro- and anti-angiogenic factors in the cornea, details of the angiogenic process are gradually unveiled. Of note, corneal inflammation and neovascularization associated with severe limbal stem cell (LSC) deficiency is a clinically challenging issue in that the condition persists long after the initial insult, and will not improve without transplantation of LSCs. However, to date the molecular mechanism by which LSC transplantation restores corneal avascularity is not fully understood. In addition to discussing major pro-angiogenic factors involved in corneal neovascularization, this review article also focuses on possible molecular mechanisms underlying persistent inflammation and neovascularization following severe LSC deficiency, and anti-angiogenic factors expressed by human limbo-corneal epithelial cells (HLCECs). Most of the recently discovered corneal anti-angiogenic factors belong to extracellular matrix proteins that acquire angio-inhibitory activity only after proper proteolytic processing. Our recent findings showed that the secretion of endostatin (derived from basement membrane collagen XVIII) and restin (from collagen XV) by HLCECs were enhanced when HLCECs were cultivated on amniotic membrane (AM). This adds to the advantage of transplanting ex vivo expanded HLCECs cultivated on AM in that the anti-angiogenic activity of the epithelial cells is augmented in a physiological way. Furthermore, proteomic profiling of HLCECs and human conjunctival epithelial cells (HCECs) identified a 14-3-3 protein (stratifin) preferentially expressed by HLCECs. In addition to functioning as a cell cycle controller, keratinocyte-derived stratifin induces MMPs which are involved in the generation of restin (by MMP-1) and endostatin (by MMP-3). These findings highlight the significance of delicate epithelial-matrix interactions in the maintenance of corneal avascularity.
Bookmarks Related papers MentionsView impact
Proceedings of the National Academy of Sciences, 1987
Bookmarks Related papers MentionsView impact
Life Sciences, 1994
Binding experiments were performed with [3H]ouabain on cultured human umbilical vein endothelial ... more Binding experiments were performed with [3H]ouabain on cultured human umbilical vein endothelial cells (huvEC). Saturation studies yielded a binding capacity (Bmax) of 820 +/- 81 fmole/mg pr.(n = 4) and dissociation constant (KD) of 11.7 +/- 2.1nM (n = 4) in K(+)-free buffer for specific [3H] ouabain binding on these cells. External K+ inhibited this binding in a dose-dependent manner. The mean value of Bmax is equivalent to about 4 x 10(5) sites per cell, comparable with that of smooth muscle cell. These data demonstrated the presence of specific [3H]ouabain binding linked to Na+/K+ pump, consistent with the observations of ouabain-sensitive 86Rb uptake in huvEC. Effect of cholesterol enrichment was also studied. Incubation in media supplemented with cholesterol-phospholipid liposomes of molar ratio of 2:1 for 18 hours reduced the Bmax by 31% (P < 0.05) without significantly changed the value of KD. This reduction of [3H]ouabain binding appeared to be specific for cholesterol since liposome made with pure phospholipid did not alter binding. Recent findings indicate that cholesterol-enrichment and plasma lipoproteins enhance vascular contractile response, our results suggest that the cholesterol-enrichment of endothelial cells may also indirectly affect the vascular response via disturbing the function of Na+/K+ pump.
Bookmarks Related papers MentionsView impact
Life Sciences, 1997
Bookmarks Related papers MentionsView impact
Life Sciences, 1997
Bookmarks Related papers MentionsView impact
Life Sciences, 1999
Bookmarks Related papers MentionsView impact
Journal of Surgical Research, 2004
Bookmarks Related papers MentionsView impact