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Megison SM, Dunn CW, Horton JW, Chao H. Effects of relief of biliary obstruction on mononuclear phagocyte system function and cell mediated immunity. Br J Surg 1991; 78:568-71. [PMID: 2059808 DOI: 10.1002/bjs.1800780516] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Obstructive jaundice causes depression of immune system function but it is unclear at present how rapidly immune function recovers after relief of biliary obstruction. To address this issue, we studied 218 Sprague-Dawley rats with common bile duct obstruction. Mononuclear phagocyte function, cell mediated immune function, portal-systemic shunt fraction, liver function tests, and liver histology were evaluated in normal (sham) rats, obstructed rats, and at weekly intervals after relief of biliary obstruction. Hepatic uptake of radiolabelled bacteria was 82 per cent in sham rats and 66 per cent in rats 21 days after CBD obstruction (P less than 0.05). Phagocytic activity returned to normal within 7 days after choledochoduodenostomy. Cell mediated immunity, measured by skin graft rejection, was significantly prolonged in the obstructed group (P less than 0.05) but had returned to normal 7 days after biliary diversion. Return of hepatocellular function, as measured by liver function tests, paralleled recovery of immune function. This study demonstrates prompt recovery of the immune system after internal biliary drainage for obstructive jaundice. This finding is in contrast to previous studies that demonstrated persistent immune suppression months after biliary diversion. These data may have implications concerning the usefulness of internal biliary drainage before surgery in patients with obstructive jaundice.
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77
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Abstract
Many models of intestinal ischemia in the rat have been described yielding mortality rates of 8-80% following superior mesenteric artery (SMA) occlusion for periods of 1-85 min. These results have been difficult to reliably reproduce in our lab. Based on our theory that these inconsistent findings are secondary to individual variability in collateral circulation, we have developed a new model for intestinal ischemia with reproducible and consistent mortality. Male Sprague-Dawley rats weighting 300-400 g underwent celiotomy and evisceration. Occlusion of the superior mesenteric artery just distal to the right colic artery was achieved. Collateral arcades from the right colic artery and the jejunal arteries proximal to the site of occlusion were ligated and the bowel was returned to the abdomen for the remainder of the ischemic period. SMA occlusion alone and SMA occlusion with interruption of collateral flow were evaluated and compared for severity of ischemic injury reflected by mortality and for reproducibility of ischemia and mortality. Quantitative measurements of blood flow for each technique were made using radiolabeled microspheres, and a survival curve for SMA occlusion with collateral ligation was constructed. SMA occlusion alone in the rat is not a reliable model for mesenteric ischemia because the resulting ischemic injury is inconsistent and not reproducible. SMA occlusion with collateral ligation produced more severe and reproducible ischemia with greater mortality than did SMA occlusion alone. This technique produced mortality rates that were reproducible and were more consistently related to duration of ischemia.
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78
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Megison SM, Horton JW, Chao H, Walker PB. Prolonged survival and decreased mucosal injury after low-dose enteral allopurinol prophylaxis in mesenteric ischemia. J Pediatr Surg 1990; 25:917-21. [PMID: 2401948 DOI: 10.1016/0022-3468(90)90204-m] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Previous studies demonstrating protective effects of allopurinol in intestinal ischemia have evaluated intravenous allopurinol (presently unavailable for human use) or enteral allopurinol at supranormal doses and, therefore, have questionable clinical relevance. To address this problem, we evaluated the protective effects of clinically used doses of enteral allopurinol in rats with intestinal ischemia. Forty male Sprague-Dawley rats (weighing 300 to 400 g) received enteral allopurinol (10 mg/kg) or water daily for 1 week. Rats were then subjected to superior mesenteric artery occlusion with interruption of collateral flow for 20 minutes to produce ischemic injury to the intestine. Segmental small bowel resections were performed in 10 control rats and 10 allopurinol-treated rats before and after reperfusion to identify histopathologic evidence of reperfusion injury. Mucosal injury was quantitated using a grading scale of 0 to 5 (5 being most severe). The remaining 20 rats (10 in each group) were observed for mortality (death within 7 days) after reperfusion. Mucosal injury after reperfusion was graded at 4.4 +/- 0.20 in controls versus 2.3 +/- 0.23 in the treated group (P less than .001). In addition, there was a significant increase in mucosal damage in the control group when postreperfusion specimens were compared with specimens taken before reperfusion (2.8 +/- 0.19 before and 4.4 +/- 0.20 after reperfusion, P less than .001). Injury score for the allopurinol-treated group did not significantly increase after reperfusion. Survival was 50% in the water-fed control group compared with 100% survival in allopurinol-treated rats (P = .016). We conclude that enteral allopurinol in the presently available form and dose is effective in reducing mesenteric reperfusion injury.
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79
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Megison SM, Horton JW, Chao H, Walker PB. High dose versus low dose enteral allopurinol for prophylaxis in mesenteric ischemia. CIRCULATORY SHOCK 1990; 30:323-9. [PMID: 2350874] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Studies demonstrating protective effects of allopurinol in intestinal ischemia have been carried out using i.v. allopurinol (presently unavailable for human use) or enteral allopurinol at supra-normal doses and, therefore, have questionable clinical relevance. We evaluated the protective effects of clinically used doses of enteral allopurinol in rats with intestinal ischemia. One hundred nine male Sprague-Dawley rats (250-300 gm) received enteral allopurinol (5-30 mg/kg) or water daily for 1 week and were subjected to superior mesenteric artery occlusion for 20, 30, or 45 min. Mortality in water-fed controls after 20 min of mesenteric ischemia was 50%, but there was no mortality in rats pretreated with allopurinol (5, 10, and 20 mg/kg/day) in this group (P = 0.016). There was no reduction in mortality after allopurinol pretreatment at any dose in rats with 30 or 45 min of ischemia. We concluded that 1) prolonged intestinal ischemia causes lethal damage during the hypoperfusion phase that cannot be prevented by allopurinol pretreatment even at supra-normal doses, and 2) allopurinol at recommended enteral doses (5-10 mg/kg/day) can reduce morality from reperfusion injury when the phase of hypoperfusion is not, in itself, lethal. Allopurinol is effective in reducing reperfusion injury in the currently available enteral form in dose ranges that should not cause prohibitive side effects.
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80
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Abstract
Heparin-induced hypoaldosteronism leading to hyperkalemia is an uncommon adverse effect. It appears as though heparin blocks an enzymatic step in the synthesis of aldosterone, and reduced aldosterone levels may be evident as early as four days after initiation of therapy. Although all patients who receive heparin may have reduced aldosterone levels, most are able to compensate through increased renin production and therefore remain asymptomatic. However, patients on prolonged heparin therapy or those unable to adequately increase renin production (e.g., patients with diabetes or renal insufficiency) may exhibit signs of hypoaldosteronism, such as hyperkalemia.
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81
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Megison SM, Dunn CW, Horton JW, Chao H. Immunologic recovery after biliary drainage in obstructive jaundice. CURRENT SURGERY 1989; 46:383-5. [PMID: 2805777] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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82
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Aihara H, Alston-Garnjost M, Avery RE, Barbaro-Galtieri A, Barker AR, Barnett BA, Bauer DA, Bay A, Bobbink GJ, Buchanan CD, Buijs A, Caldwell DO, Chao H, Chun S, Clark AR, Cowan GD, Crane DA, Dahl OI, Daoudi M, Derby KA, Eastman JJ, Eberhard PH, Edberg TK, Eisner AM, Enomoto R, Erné FC, Fairfield KH, Hauptman JM, Hofmann W, Hylen J, Kamae T, Kaye HS, Kenney RW, Khacheryan S, Kofler RR, Langeveld WG, Layter JG, Lin WT, Linde FL, Loken SC, Lu A, Lynch GR, Madaras RJ, Magnuson BD, Masek GE, Mathis LG, Matthews JA, Maxfield SJ, Miller ES, Moses W, Nygren DR, Oddone PJ, Paar HP, Park SK, Pellett DE, Pripstein M, Ronan MT, Ross RR, Rouse FR, Schwitkis KA, Sens JC, Shapiro G, Shen BC, Smith JR. Charged-hadron inclusive cross sections and fractions in e+e- annihilation at sqrt s =29 GeV. PHYSICAL REVIEW LETTERS 1988; 61:1263-1266. [PMID: 10038747 DOI: 10.1103/physrevlett.61.1263] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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83
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Aihara H, Alston-Garnjost M, Avery RE, Barbaro-Galtieri A, Barker AR, Barnett BA, Bauer DA, Bay A, Bengtsson H, Bobbink GJ, Buchanan CD, Buijs A, Caldwell DO, Chao H, Chun S, Clark AR, Cowan GD, Crane DA, Dahl OI, Daoudi M, Derby KA, Eastman JJ, Eberhard PH, Edberg TK, Eisner AM, Enomoto R, Erné FC, Fairfield KH, Hauptman JM, Hofmann W, Hylen J, Kamae T, Kaye HS, Kenney RW, Khacheryan S, Kofler RR, Langeveld WG, Layter JG, Lin WT, Linde FL, Loken SC, Lu A, Lynch GR, Madaras RJ, Magnuson BD, Masek GE, Mathis LG, Matthews JA, Maxfield SJ, Miller ES, Moses W, Nygren DR, Oddone PJ, Paar HP, Park SK, Pellett DE, Pripstein M, Ronan MT, Ross RR, Rouse FR, Schwitkis KA, Sens JC, Shapiro G, Shen BC. Charmonium production in photon-photon collisions. PHYSICAL REVIEW LETTERS 1988; 60:2355-2358. [PMID: 10038330 DOI: 10.1103/physrevlett.60.2355] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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84
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McEwen B, Chao H, Spencer R, Brinton R, Macisaac L, Harrelson A. Corticosteroid receptors in brain: relationship of receptors to effects in stress and aging. Ann N Y Acad Sci 1987; 512:394-401. [PMID: 3327425 DOI: 10.1111/j.1749-6632.1987.tb24975.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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85
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Weissmann B, Chao H. Heparin trisaccharides with nonreducing 2-amino-2-deoxy-alpha-D-glucopyranosyl end-groups suitable as substrates for catabolic enzymes. Carbohydr Res 1986; 154:217-28. [PMID: 3791294 DOI: 10.1016/s0008-6215(00)90034-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Heparin trisaccharides having the sequence O-(2-amino-2-deoxy-alpha-D-glucopyranosyl)-(1----4)-O-alpha-L- idopyranosyluronic acid-(1----4)-2,5-anhydro-D-[1-3H]mannitol have been prepared, as substrate models for studying sulfatases of heparan sulfate catabolism, by alpha-L-iduronidase cleavage of previously reported heparin tetrasaccharides, with additional chemical and enzymic modification as required. Three series are described, including isomeric sulfate esters of that trisaccharide with no N-substituent, with N-acetyl substitution, and with N-sulfate substitution. New features of the substrate specificity of the hydrolases used, including iduronate sulfatase, alpha-L-iduronidase, glucosamine 6-sulfate sulfatase, and heparin sulfamidase, were observed, and simple procedures for partial purification of these hydrolases are reported. The structures assigned to the trisaccharides are supported by the mode of preparation, reactions, regularities in electrophoretic behavior, and identities of the products of deamination.
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86
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Yu ZS, Chao H, Qiao L, Qian DS, Ye YH. Epidemiologic survey of vibration syndrome among riveters, chippers and grinders in the railroad system of the People's Republic of China. Scand J Work Environ Health 1986; 12:289-92. [PMID: 3490686 DOI: 10.5271/sjweh.2150] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Vibration syndrome caused by hand-held vibrating tools in 14 locomotive and rolling stock plants in four regions of the People's Republic of China (south, north, middlewest, and northeast) and the influence of climatic factors on its prevalence rate were studied. For 1,028 male workers (705 riveters, 284 chippers, and 39 grinders), the prevalence rate of the syndrome was 13.4% and for a reference group of 256 workers it was 1.6%. The prevalence rate of white finger in the four regions differed and was higher in northeast and north China than in south and middlewest China. This finding suggests that cold climate and humidity may be causative factors of the vibration syndrome.
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Chao H, Chung LW. Neonatal imprinting and hepatic cytochrome P-450. Immunochemical evidence for the presence of a sex-dependent and neonatally imprinted form(s) of hepatic cytochrome P-450. Mol Pharmacol 1982; 21:744-52. [PMID: 7110121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
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88
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Chung LW, Colvin M, Chao H. Neonatal imprinting and hepatic cytochrome P-450. II. Partial purification of a sex-dependent and neonatally imprinted form(s) of cytochrome P-450. JOURNAL OF SUPRAMOLECULAR STRUCTURE AND CELLULAR BIOCHEMISTRY 1981; 15:193-204. [PMID: 6965091 DOI: 10.1002/jsscb.1981.380150210] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
A new form of cytochrome P-450 was partially purified from hepatic microsomes of neonatally imprinted rats (adult male and adult male castrated at four weeks of age). This new form of cytochrome P-450 appears to have an apparent molecular weight of approximately 50,000 daltons as judged by sodium dodecyl sulfate polyacrylamide gel electrophoresis. It appears that this form of cytochrome P-450 is either absent or present in low concentrations in cytochrome P-450 preparations isolated from neonatally nonimprinted rats (adult female and adult male castrated at birth). Reconstitution of testosterone hydroxylase and benzphetamine N-demethylase activities of this partially purified cytochrome P-450 revealed that the presence of testosterone 16 alpha-hydroxylase activity, an imprintable microsomal enzyme, was in parallel with the imprinting status of the animals; a significantly higher activity was detected in the neonatally imprinted than that of the nonimprinted animals. This was in contrast to the nonimprintable benzphetamine N-demethylase, testosterone 7 alpha- and 6 beta-hydroxylase activities which exhibited no correlation with the imprinting status of the animals. We have prepared antisera from rabbits using the partially purified cytochrome P-450 preparations from adult male rats as antigens. These antisera inhibited microsomal testosterone 16 alpha- and 7 alpha-hydroxylase activities in a concentration-dependent manner, without impairing 6 beta-hydroxylase activity. These data suggest that the partially purified cytochrome P-450 from adult male rats consists of both imprintable (16 alpha-) and nonimprintable (7 alpha-) testosterone hydroxylase activities.(ABSTRACT TRUNCATED AT 250 WORDS)
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89
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Weissmann B, Chao H, Chow P. A glucosamine O,N-disulfate O-sulfohydrolase with a probable role in mammalian catabolism of heparan sulfate. Biochem Biophys Res Commun 1980; 97:827-33. [PMID: 6451222 DOI: 10.1016/0006-291x(80)90338-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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90
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Chung LW, Chao H. Neonatal imprinting and hepatic cytochrome P-450. I. Comparison of testosterone hydroxylation in a reconstituted system between neonatally imprinted and nonimprinted rats. Mol Pharmacol 1980; 18:543-9. [PMID: 6780782] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
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91
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Castro Costa MR, Edelstein SB, Castiglione CM, Chao H, Breakefield XO. Properties of monoamine oxidase in control and Lesch-Nyhan fibroblasts. Biochem Genet 1980; 18:577-90. [PMID: 7437013 DOI: 10.1007/bf00484403] [Citation(s) in RCA: 40] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Monoamine oxidase activity of the A type was measured in homogenates of cultured human skin fibroblasts. Twenty-four control lines had activities ranging over fifty-fold with an apparent bimodal distribution. Activity in fibroblasts from 20 patients with the Lesch-Nyhan syndrome fell in the low portion of the normal distribution with a mean activity about 50% that of the control mean (p < 0.05). In a subgroup of control and Lesch-Nyhan lines with levels of enzyme activity from 0.9 to 179 pmol/min/mg protein, monoamine oxidase was similar with respect to apparent Km for tryptamine, thermal stability at 56 C, and sensitivity to clorgyline. Thus the lower mean levels of activity observed in the Lesch-Nyhan as compared to control fibroblasts were not associated with other altered properties of the enzyme. The bimodal distribution of enzyme activity suggests that a genetic polymorphism for monoamine oxidase may control levels of activity expressed in fibroblasts.
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Chao H, Peiper SC, Philpott GW, Parker CW, Aach RD. Selective uptake of specifically purified antibodies to carcinoembryonic antigen of human adenocarcinoma. RESEARCH COMMUNICATIONS IN CHEMICAL PATHOLOGY AND PHARMACOLOGY 1974; 9:749-61. [PMID: 4142100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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93
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Ikehara Y, Molnar J, Chao H. Inhibition of glycoprotein synthesis by cycloheximide in liver and Ehrlich tumor cells. BIOCHIMICA ET BIOPHYSICA ACTA 1971; 247:486-95. [PMID: 5125632 DOI: 10.1016/0005-2787(71)90035-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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94
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Molnar J, Chao H, Ikehara Y. Phosphoryl-N-acetylglucosamine transfer to a lipid acceptor of liver microsomal preparations. BIOCHIMICA ET BIOPHYSICA ACTA 1971; 239:401-10. [PMID: 5113503 DOI: 10.1016/0005-2760(71)90033-6] [Citation(s) in RCA: 62] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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95
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Tetas M, Chao H, Molnar J. Incorporation of carbohydrates into endogenous acceptors of liver microsomal fractions. Arch Biochem Biophys 1970; 138:135-46. [PMID: 4315690 DOI: 10.1016/0003-9861(70)90292-4] [Citation(s) in RCA: 77] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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96
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97
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Molnar J, Markovic G, Chao H, Molnar Z. Glycoproteins of Ehrlich asctes carcinoma cells. Separation of plasma and endoplasmic reticular membrane fragments. Arch Biochem Biophys 1969; 134:524-32. [PMID: 5354775 DOI: 10.1016/0003-9861(69)90314-2] [Citation(s) in RCA: 35] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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98
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Molnar J, Chao H, Markovic G. Subcellular site of structural glycoprotein synthesis in Ehrlich ascites tumor. Arch Biochem Biophys 1969; 134:533-8. [PMID: 5354776 DOI: 10.1016/0003-9861(69)90315-4] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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