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1. |
LOCALIZATION OF CRYPTIC TOLEROGENIC EPITOPES IN THE α1-HELICAL REGION OF THE RT1.AUALLOANTIGEN1 |
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Transplantation,
Volume 63,
Issue 10,
1997,
Page 1373-1379
Wang Min,
Stepkowski Stanislaw,
Yu Jiang,
Wang Mou-er,
Kahan2 Barry,
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摘要:
Background.Transplantation tolerance is induced by perioperative administration of host class I major histocompatibility complex proteins bearing donor-type amino acid (a.a.) epitopes substituted for native residues. Herein we demonstrate that two cryptic tolerogenic a.a. epitopes are localized in the α1-helical region of the rat RT1.Auclass I major histocompatibility complex alloantigen.Methods.Three allochimeric proteins were produced by superimposing the nucleotides encoding donor-type RT1.Aua.a. onto the host RT1.Aabackbone using the polymerase chain reaction-based method of gene splicing with overlap extension. We substituted nucleotide sequences encoding all nine (Arg62, Glu63, Gln65, Gly66, Gly69, His70, Val73, Asn74, and Asn77; α1hu62-77-RT1.Aa), the first four (Arg62, Glu63, Gln65, and Gly69; α1hu62-69-RT1.Aa), or the last four (His70, Val73, Asn74, and Asn77; α1hu70-77-RT1.Aa) α1-helical RT1.Aupolymorphic a.a. in RT1.AacDNA. A baculovirus/Spodoptera frugiperda(Sf9) expression system was harnessed for production of the proteins.Results.Untreated ACI (RT1a) rats reject Wistar-Furth (WF; RT1u) heart allografts at a mean survival time of 8.9±1.0 days. A single portal vein injection of 10 μg of α1hu62-77-RT1.Aaprotein had no effect on the survival of WF heart allografts (10.5±0.6 days) in ACI hosts. Interestingly, portal vein administration of 10 μg of α1hu70-77-RT1.Aainduced transplantation tolerance toward WF grafts in four of six untreated ACI recipients (>100 days;P<0.01). In contrast, 10 μg of α1hu62-69-RT1.Aaonly prolonged the survival of WF heart allografts in ACI hosts (14.0±0.8 days;P<0.01). However, when combined with a 7-day course of cyclosporine (4.0 mg/kg; oral gavage), α1hu62-69-RT1.Aainduced tolerance toward WF allografts in five of seven ACI recipients (>170 days;P<0.01). Long-term survival of WF grafts was not achieved when a 7-day course of cyclosporine was administered alone (14.3±3.0 days) or with 10 μg of α1hu62-77-RT1.Aa(14.6±0.6 days; NS).Conclusions.These findings suggest that the use of allochimeric proteins may provide a novel approach to the induction of tolerance.
ISSN:0041-1337
出版商:OVID
年代:1997
数据来源: OVID
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2. |
INHALED NITRIC OXIDE ATTENUATES REPERFUSION INJURY IN NON-HEARTBEATING-DONOR LUNG TRANSPLANTATION1,2 |
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Transplantation,
Volume 63,
Issue 10,
1997,
Page 1380-1386
Bacha3 Emile,
Sellak Hassan,
Murakami Shinya,
Mazmanian Guy-Michel,
Détruit Hélène,
de Montpreville Vincent,
Chapelier Alain,
Libert Jean-Marie,
Dartevelle Philippe,
Hervé4 Philippe,
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摘要:
Background.Non-heartbeating-donor (NHBD) lung transplantation could help reduce the current organ shortage. Polymorphonuclear neutrophil (PMN) activation plays a pivotal role in ischemia-reperfusion injury (I-R), and can be inhibited by nitric oxide (NO). We hypothesized that inhaled NO might be beneficial in NHBD lung transplantation.Methods.The effect of inhaled NO on PMNs was studied by measuring in vivo PMN lung sequestration (myeloperoxidase activity) and adhesion of recipient circulating PMNs to cultured pulmonary artery endothelial cells (PAECs) in vitro. Pigs were randomly assigned to an NO or a control group (n=9 each). In the NO group, cadavers and recipients were ventilated with oxygen and 30 parts per million of NO. After 3 hr of postmortem in situ warm ischemia and 2 hr of cold ischemia, left allotransplantation was performed. The right pulmonary artery was ligated, and hemodynamic and gas exchange data were recorded hourly for 9 hr. Recipient PMN adherence to tumor necrosis factor-α- and calcium ionophore-stimulated PAECs was measured before and after reperfusion, and lung PMN sequestration was determined after death.Results.NO-treated animals exhibited lowered pulmonary vascular resistance (P<0.01), as well as improved oxygenation (P<0.01) and survival (P<0.05). Adhesion of PMNs to PAECs was inhibited in the NO group before (P<0.001) and after reperfusion (P<0.0001). Lung PMN sequestration was reduced by NO (P<0.05).Conclusions.Inhaled NO attenuates I-R injury after NHBD lung transplantation. This is likely due to the prevention of I-R-induced pulmonary vasoconstriction and to the direct effect on peripheral blood PMN adhesion to endothelium, which results in reduced sequestration and tissue injury.
ISSN:0041-1337
出版商:OVID
年代:1997
数据来源: OVID
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3. |
BONE MARROW TRANSPLANTATION IN NEWBORN RATS WITH MUCOPOLYSACCHARIDOSIS TYPE VIBiochemical, Pathological, and Clinical Findings1 |
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Transplantation,
Volume 63,
Issue 10,
1997,
Page 1386-1393
Simonaro2 Calogera,
Haskins3 Mark,
Kunieda4 Tetsuo,
Evans5 Sydney,
Visser6 Jan,
Schuchman2,7 Edward,
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摘要:
Background.Mucopolysaccharidosis type VI (MPS VI) is the lysosomal storage disorder caused by the deficient activity of arylsulfatase B (ASB). In this study, we evaluated bone marrow transplantation (BMT) for the treatment of MPS VI and the effects of irradiation on the survival and engraftment of bone marrow-transplanted neonatal rats.Methods.One- to 2-day-old MPS VI rats were injected with normal bone marrow after irradiation with 200, 400, or 800 cGy. Ninety percent of the animals receiving a single dose of 200 cGy (n=30) survived the procedure, whereas irradiation with 400 cGy (n=23) or 800 cGy (n=12) resulted in significant mortality (78% and 100%, respectively). Engraftment was monitored by determining ASB activities in peripheral white blood cells and by Y chromosome in situ hybridization analysis. Fifty-two percent of the animals from the 200-cGy group engrafted for up to 8 months after BMT; among the five animals that survived the 400-cGy dose, all engrafted. In comparison, only 20% of nonirradiated animals engrafted at low levels. Of the 24 engrafted animals that were monitored for 8 months after BMT, clinical and/or radiographic improvements were noted in only one (BMT animal 3). Enzymatic analysis revealed that the ASB activities in the reticuloendothelial organs of this animal, as well as two other engrafted but clinically unimproved animals (BMT animals 1 and 2), were normal or near normal; correspondingly, the glycosaminoglycan levels in these organs were significantly reduced. Consistent with the clinical and biochemical observations, light and electron microscopic findings were more improved in BMT animal 3 as compared with BMT animals 1 and 2, although a reduction of storage was evident in each of these transplant recipients, particularly in the trachea and aorta, two tissues that are characteristic sites of pathology in human patients.Conclusions.These results indicate that BMT in newborn MPS VI patients may prevent many of the pathological and clinical findings in this disorder, but is likely to have very limited and unpredictable effects on the skeletal abnormalities.
ISSN:0041-1337
出版商:OVID
年代:1997
数据来源: OVID
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4. |
PERMANENT AND SPECIFIC TRANSPLANTATION TOLERANCE INDUCED BY A NONMYELOABLATIVE TREATMENT TO A WIDE VARIETY OF ALLOGENEIC TISSUESI. Induction of Tolerance by a Short Course of Total Lymphoid Irradiation and Selective Elimination of the Donor-Specific Host Lymphocytes1 |
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Transplantation,
Volume 63,
Issue 10,
1997,
Page 1394-1399
Prigozhina Tatyana,
Gurevitch Olga,
Zhu Jun,
Slavin2 Shimon,
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摘要:
The long-term success of organ transplantation is limited by complications resulting from consistent nonspecific immunosuppression. Induction of stable, donor-specific tolerance remains the main goal of transplantation immunology. In this article, a new, nonmyeloablative method is described for induction of transplantation tolerance to fully mismatched bone marrow cells (BMC), bone marrow stromal precursors, heart muscle, and skin allografts. The method is based on pretransplant conditioning with no postgraft immunosuppression, and consists of a short course (six daily fractions of 200 cGy) of total lymphoid irradiation (sTLI), followed by selective elimination of donor-specific alloreactive cells of the host escaping low-dose sTLI. Donor-specific alloreactive cells were activated by intravenous inoculation with a high dose of donor BMC (3×107cells) 1 day after sTLI, and eliminated by a single intraperitoneal dose (200 mg/kg) of cyclophosphamide given 1 day after cell transfer. Infusion of a low number of T cell-depleted BMC (3×106cells) after tolerogenic preconditioning converted recipients to stable mixed chimeras free of graft-versus-host disease. The same treatment provided long-lasting acceptance of heterotopically transplanted allografts of the heart muscle and of the stromal precursors to the hematopoietic microenvironment. This treatment also led to acceptance and life-long survival of full-thickness donor skin allografts. However, skin allografts survived only in mice that received donor T cell-depleted BMC after cyclophosphamide and had 20-50% donor cells in the blood. Our results suggest that after sTLI, additional selective clonal deletion of residual host cells induces a state of long-lasting specific tolerance to a wide variety of donor-derived tissues.
ISSN:0041-1337
出版商:OVID
年代:1997
数据来源: OVID
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5. |
THE ASYSTOLIC DONOR SYNDROMETransaminitis and Thrombocytopenia after Non-Heartbeating Renal Transplantation1 |
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Transplantation,
Volume 63,
Issue 10,
1997,
Page 1400-1404
Andrews2,3 Peter,
Denton Mark,
Compton Frederick,
Koffman C.,
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摘要:
Background.The use of kidneys from non-heartbeating donors (NHB) remains controversial. An increased incidence of delayed primary function and primary nonfunction is common. We report a characteristic syndrome of transaminitis and thrombocytopenia after NHB renal transplantation, which may be predictive of graft outcome.Methods.Two case histories are presented, followed by a retrospective analysis of 38 NHB renal grafts performed at Guy's Hospital from 1988 to 1994. Changes in alanine aminotransferase (ALT) and platelet count were compared between recipients of kidneys from NHB and heartbeating donors (HB). To control for possible effects of antilymphocyte globulin (ALG), two matched control groups receiving HB kidneys with (n=32) and without (n=32) ALG were also compared.Results.ALT was elevated in 32 of 38 (84%) of NHB recipients and 19 of 64 (30%) controls (P<0.001). Mean peak ALT was 172±20 U/L in NHB and 42±6 U/L in HB kidneys (P<0.001). Use of ALG did not influence mean peak ALT. Elevated ALT predicted impaired graft function (P<0.02) and was associated with an increased length of delayed primary function (P<0.001) and risk of transplant nephrectomy (P<0.05). Thrombocytopenia (<100×109cells/L) occurred in 18 of 38 (47%) NHB recipients and in 20 of 64 (31%) controls (P<0.05). Mean nadir platelet count (×109cells/L) was 113±10 in NHB, 128±9 in HB with ALG, and 164±9 in HB without ALG (bothP<0.05 vs. NHB). Patients who underwent graft nephrectomy (n=9) had a disproportionate fall in platelet count (mean nadir, 80±11×109cell/L;P<0.05).Conclusions.Transaminitis and thrombocytopenia occur commonly after NHB kidney transplantation and are predictive of graft outcome. Recognition of these changes may assist the early management of NHB renal recipients, and also reduce investigation of “anomalous” results in this setting.
ISSN:0041-1337
出版商:OVID
年代:1997
数据来源: OVID
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6. |
OUTCOME OF EN BLOC AND SINGLE KIDNEY TRANSPLANTATION FROM VERY YOUNG CADAVERIC DONORS1,2,3,4,5,6 |
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Transplantation,
Volume 63,
Issue 10,
1997,
Page 1405-1410
Satterthwaite Roger,
Aswad Saleh,
Sunga Victor,
Shidban Hamid,
Mendez Rafael,
Bogaard Thomas,
Asai Paul,
Khetan Umakant,
Magpayo Marisa,
Mendez7 Robert,
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摘要:
Background.The optimal use of very young cadaveric kidneys (from donors less than 4 years old) remains controversial. High rates of technical complications and poor functional results compared with adult donor kidneys have been reported. The use of en bloc transplantation to overcome these problems has been advocated, although en bloc transplantation halves the number of potential transplants from very young donors.Methods.We studied the technical and functional results of 91 transplants from very young donors performed at our institution between 1984 and 1995. This included 59 single and 22 en bloc procedures involving first transplants and 7 single and 3 en bloc procedures involving retransplantation. Individual surgeon preference dictated the use of either the single or en bloc technique. Kidneys smaller than 6 cm tended to be transplanted en bloc, and lighter patients were generally given preference for receiving pediatric kidneys. Patients received sequential cyclosporine-based quadruple immunosuppression.Results.En bloc kidneys had a 1-year and 5-year graft survival of 82% and 70%, respectively. Single kidneys had a 1-year and 5-year graft survival of 64% and 40%. Kidneys that avoided acute rejection episodes and that were transplanted into heavier or male recipients had better long-term survival. Kidneys from donors less than 2 years old did poorly whether transplanted en bloc or singly. Better HLA matching improved short-term, but not long-term, graft survival, whereas cold ischemic time did not have statistically significant association with differences in graft survival. Eleven percent of the transplants had ureteral leaks, but only one kidney was lost. Ten transplants had vascular complications leading to graft loss, whereas two episodes of arterial stenosis were successfully treated with percutaneous angioplasty.Conclusions.En bloc transplantation optimizes the outcome of transplantation with very young kidneys. We recommend induction therapy and cyclosporine immunosuppression with cyclosporine levels similar to adult target levels to minimize rejection episodes and, thus, improve outcome. These kidneys should be distributed nationally, because better HLA matching is associated with improved short-term graft survival. Our high ureteral leak rate indicates that alternatives to unstented ureteroneocystostomy should be considered.
ISSN:0041-1337
出版商:OVID
年代:1997
数据来源: OVID
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7. |
ENHANCED (CYTOMEGALOVIRUS) VIRAL REPLICATION ASSOCIATED WITH SEPTIC BACTERIAL COMPLICATIONS IN LIVER TRANSPLANT RECIPIENTS |
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Transplantation,
Volume 63,
Issue 10,
1997,
Page 1411-1415
Mutimer1 David,
Mirza Darius,
Shaw Jean,
O'Donnell Katharina,
Elias Elwyn,
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摘要:
Background.Complications of the biliary anastomosis are the principal cause of clinically serious bacterial sepsis in liver transplant recipients. Reported series suggest an association of bacterial and fungal infection with cytomegalovirus (CMV) infection, although the mechanism of this association is unclear.Methods.We examined the association of serious bacterial sepsis with CMV replication in a cohort of 106 consecutive liver transplant recipients. Sequentially collected buffy coats were examined with a polymerase chain reaction (PCR) assay that has been shown to have good predictive value for the development of CMV infection. For selected patients, CMV-specific IgM response and serum tumor necrosis factor-α (TNF-α) were also measured.Results.Ten of 13 patients with serious bacterial sepsis developed buffy coat PCR positivity, compared with 26 of 93 patients without bacterial sepsis (chi-square,P<0.001). Ten of 10 septic recipients with a seropositive liver donor developed PCR positivity. For 9 of 10 recipients, bacterial sepsis developed before PCR positivity. Bacterial sepsis was associated with high serum levels of TNF-α. Immune response to CMV (reflected by the appearance CMV-specific IgM) was apparently affected by bacterial sepsis, and IgM response was not observed for the three septic patients who died during the study period.Conclusions.We conclude that CMV replication is encouraged by serious bacterial sepsis. Replication may be promoted by high antecedent levels of TNF-α, and/or by poor immune response to CMV in the context of serious bacterial infection.
ISSN:0041-1337
出版商:OVID
年代:1997
数据来源: OVID
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8. |
PRETRANSPLANT FAMCICLOVIR AS PROPHYLAXIS FOR HEPATITIS B VIRUS RECURRENCE AFTER LIVER TRANSPLANTATION |
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Transplantation,
Volume 63,
Issue 10,
1997,
Page 1415-1419
Singh1 Nina,
Gayowski Timothy,
Wannstedt Cheryl,
Wagener Marilyn,
Marino Ignazio,
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摘要:
Liver transplantation in patients with detectable hepatitis B virus (HBV) DNA is associated with a high rate of HBV recurrence and detectable HBV DNA is often considered a contraindication for liver transplantation. Famciclovir, an oral form of the purine nucleoside penciclovir, has been shown to inhibit HBV replication. This pilot study was conducted to determine whether a 6-month course of famciclovir, administered before transplantation, was effective in inhibiting HBV replication in patients with end-stage liver disease caused by HBV and detectable HBV DNA and to assess the posttransplant clinical and virologic outcome of patients becoming HBV DNA negative with famciclovir prior to transplantation. All eight patients enrolled were hepatitis B surface antigen (HBsAg) positive; their HBV DNA levels at baseline ranged from 4.3 to 25,321 pg/ml (mean 3,661 pg/ml). Six of the eight patients were also seropositive for HBeAg. An initial decline in HBV DNA titers occurred in all patients; however, only 25% (two of eight) of the patients became HBV DNA negative before transplantation and underwent liver transplantation. Seroconversion to hepatitis B surface antibody (HBsAb) (and HBeAb in HBeAg-positive patient) was demonstrated at the conclusion of famciclovir in the transplanted patients. Both patients remain HBV DNA negative at nearly 2 years of follow-up after transplantation. HBV DNA remained detectable in 63% (five of eight) of the patients. The mean HBV DNA level for patients who became HBV DNA negative was 5.1 pg/ml versus 424 pg/ml in nonresponders. Adverse effects attributable to famciclovir were not observed in any of the patients. Future studies should assess the predictors of response to famciclovir so that patients likely to achieve good virologic outcome can be targeted for such a therapy.
ISSN:0041-1337
出版商:OVID
年代:1997
数据来源: OVID
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9. |
RELATIONSHIP BETWEEN HEPATITIS C GENOTYPE AND SEVERITY OF RECURRENT HEPATITIS C AFTER LIVER TRANSPLANTATION1,2 |
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Transplantation,
Volume 63,
Issue 10,
1997,
Page 1419-1423
Gordon3,4 Fredric,
Poterucha3 John,
Germer5 Jeff,
Zein3 Nizar,
Batts5 Kenneth,
Gross3 John,
Wiesner3 Russell,
Persing5 David,
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摘要:
Background.Recurrence of hepatitis C virus (HCV) infection after liver transplantation is universal, but the relationship between hepatitis C genotype and posttransplant outcome has been controversial. The aim of this study was to assess the relationship between hepatitis C genotype on posttransplant frequency of recurrent hepatitis, histologic severity of recurrence, and progression to cirrhosis.Methods.We studied 42 HCV RNA positive patients who received transplants between 1985 and 1994. Sera were tested for HCV RNA and protocol liver biopsies were in obtained the posttransplant period. Biopsies were scored according to the histologic activity index (HAI) and staged in a blinded fashion.Results.The distribution of hepatitis C genotypes distribution was as follows: 1a, 19 (45%); 1b, 17 (40%); 2b, 3 (7%); and 1 each of 2a, 3a, and 4a. There was histologic evidence of hepatitis in 38 of 42 (90.4%) of patients. Hepatitis C was mild, moderate, or severe (HAI>3) in 38% of grafts and minimal (HAI 0-3) in 62%. Overall HAI scores and histologic stage were higher in the genotype 1b group. Six of 17 (35%) genotype 1b patients had cirrhosis compared with 2 of 25 (8%) in the non-1b genotype group.Conclusions.(1) Histologic evidence of recurrent hepatitis C is seen in 90% of liver allografts; (2) Histologic hepatitis C recurs with similar frequency in genotype 1b and non-1b recipients; (3) Genotype 1b is associated with more severe histologic disease recurrence than non-1b genotypes; (4) Genotype 1b appears to be associated with a higher degree of posttransplant fibrosis and cirrhosis than non-1b genotypes.
ISSN:0041-1337
出版商:OVID
年代:1997
数据来源: OVID
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10. |
DECREASED PATIENT ANALGESIC REQUIREMENTS AFTER LIVER TRANSPLANTATION AND ASSOCIATED NEUROPEPTIDE LEVELS |
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Transplantation,
Volume 63,
Issue 10,
1997,
Page 1423-1429
Donovan1 Kevin,
Janicki Piotr,
Striepe Volker,
Stoica Cristina,
Franks William,
Pinson C.,
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摘要:
Background.Decreased morphine requirements have been reported after liver transplantation when compared with other types of major abdominal surgery. The aim of this study was to examine plasma concentrations of three neuropeptides involved in pain modulation-metenkephalin (ME), beta-endorphin (BE), and substance P (SP)-in patients undergoing orthotopic liver transplantation (OLT) and in control patients undergoing other liver operations. We then compared the postoperative analgesic requirements in these two groups of patients.Methods.Plasma levels of ME, BE, and SP were measured by radioimmunoassay at preincision, preemergence, and for 3 days after operation in 13 patients undergoing OLT and in 10 control patients. Patient-controlled analgesia morphine delivery was recorded for all patients postoperatively, and plasma morphine, its metabolites, and patient pain and sedation scores were also measured.Results.ME levels were elevated in all OLT patient samples when compared with control patient samples. BE levels were not significantly different at any time. SP levels were significantly decreased only in preincision and preemergence OLT patient samples. Total patient-controlled analgesia morphine delivered during the first 3 postoperative days was significantly less in OLT patients (70±8 mg) than in control patients (101±12 mg). Plasma morphine, morphine-3-glucuronide, and morphine-6-glucuronide levels were decreased in OLT patients, however, statistical significance was seen only in the morphine-6-glucuronide results.Conclusions.We have shown that postoperative analgesic requirements are decreased in OLT patients, and we suggest that associated increased peripheral ME levels may be contributing to this decreased requirement. Based on our results, circulating BE and SP are less significant factors affecting postoperative analgesic requirements.
ISSN:0041-1337
出版商:OVID
年代:1997
数据来源: OVID
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