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991.
Correlation of donor nutritional status with sinusoidal lining cell viability and liver function in the rat 总被引:5,自引:0,他引:5
G R Morgan J R Sanabria P A Clavien M J Phillips C Edwards P R Harvey S M Strasberg 《Transplantation》1991,51(6):1176-1183
We have demonstrated that the sinusoidal lining cell injury sustained by rat liver allografts during hypothermic storage is a critical determinant of graft viability. The present study was designed to examine the effect of donor nutritional status on hepatic microcirculation and graft function. Rat livers from four nutritional groups (group I, fasted; group II, fed; group III, intraperitoneal glucose; and group IV, fed plus intraperitoneal glucose) were excised and stored for 24 hr in Marshall's isotonic citrate solution. Then the livers were perfused under anoxic conditions with trypan blue. The percentage of nonviable SLC in each group was 26.7 +/- 8.1, 24.9 +/- 7.9, 17.6 +/- 6.9, and 5.9 +/- 1.9 in groups I, II, III, and IV respectively; i.e., there was a significant improvement in SLC viability with nutritional repletion in group IV. Electron microscopy was performed on livers from groups I and IV following 30-hr preservation in University of Wisconsin solution and after 16-hr preservation in Marshall's isotonic citrate solution. Biopsies were taken at the end of storage and after 1 hr of reperfusion at 37 degrees C. At the end of preservation group IV livers contained glycogen and had much more normal liver ultrastructure than group I livers. After reperfusion there was partial recovery of normal SLC morphology in both groups and depletion of glycogen in group IV. Liver function was studied on the isolated perfused rat liver system at 37 degrees C following 30-hr storage in UW solution. Transaminase release into the perfusate was significantly lower in nutritionally repleted livers than in livers from fasted animals. A significant reduction in perfusate platelet count occurred only in livers from fasted animals. The results show that nutritional repletion can reduce the injury of cold preservation to both hepatocytes and endothelial cells and improve liver function in the postpreservation period. 相似文献
992.
T J Wilton D J Hosking E Pawley A Stevens L Harvey 《The Journal of bone and joint surgery. British volume》1987,69(5):765-768
In this study 201 elderly patients with femoral neck fractures were compared with 30 osteomalacic patients with the same injury. Hypocalcaemia and a raised alkaline phosphatase level are common biochemical abnormalities in elderly patients with femoral neck fractures. In only a minority of patients, however, were they associated with histologically proven osteomalacia. By using the combination of hypocalcaemia and a raised alkaline phosphatase it is possible to identify a subgroup (approximately 10% of all admissions) in whom osteomalacia is relatively likely. 相似文献
993.
A component of Aspergillus fumigatus, Ag 7, previously identified as a major antigen for patients with allergic bronchopulmonary aspergillosis, has been isolated by gel filtration and further purified by affinity chromatography using monospecific antiserum. The antigen, which binds both specific IgG and IgE antibodies, was shown to be a high molecular weight, 150-200 kD, heat-stable glycoprotein, which binds to concanavalin A, suggesting the presence of alpha-D mannopyrannoside, or alpha-D glucopyrannoside end residues. On sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) it had a subunit of molecular weight 36 kD (with or without prior reduction), which retained antigenicity and allergenicity when tested with patients' sera. 相似文献
994.
The amino-terminal region of pp60c-src has a modulatory role and contains multiple sites of tyrosine phosphorylation. 总被引:8,自引:0,他引:8
The c-src gene product from either platelet-derived growth factor treated cells or from polyomavirus-infected cells migrates anomalously on gels, displays enhanced kinase activity, and contains additional sites of tyrosine phosphorylation within its amino-terminus. To probe the importance of these post-translational modifications, each of the five amino-terminal tyrosine residues (residues 90, 92, 131, 136, and 149) was altered to phenylalanine using site-directed mutagenesis. Except for the 136F variant, the mutants displayed enhanced kinase activity, albeit at a low level shown insufficient to induce focus formation in NIH3T3 cells. Mutagenesis of residues adjacent to tyrosines 90 and 92 also resulted in variants with enhanced kinase activity indicating that the region and not the tyrosines per se, may be involved in regulating this activity. Fingerprinting analysis demonstrated that the enhanced kinase activity brought about by these mutations occurred through a mechanism which appears to be independent of the phosphorylation state of Tyr 416 and possibly Tyr 527. Upon treatment of cells with vanadate both amino-terminal variants and transforming mutants of pp60c-src displayed a slower migrating form, designated p60+. Hence, the appearance of these p60+ proteins may be elicited either by mutations that enhance the transforming activity of pp60c-src or by perturbations within the amino-terminal region of the enzyme. The retarded mobility of p60+ was shown to be due in part to additional tyrosine phosphorylations residing at its amino-terminus. The demonstration that p60+ could be resolved into multiple bands and that amino-terminal fragments containing phosphorylated tyrosine residues were obtained regardless of which of the five tyrosines in the region was altered to phenylalanine indicates that there are multiple sites of tyrosine phosphorylation within the amino-terminal region of pp60c-src. 相似文献
995.
Effective salvage chemotherapy with etoposide, dactinomycin, and methotrexate in refractory germ cell cancer. Australasian Germ Cell Trial Group 总被引:1,自引:0,他引:1
J A Levi D Thomson V Harvey G Gill D Raghavan M Tattersall R Snyder I Burns T Sandeman M Byrne 《Journal of clinical oncology》1990,8(1):27-32
Fifty-one patients with advanced germ cell malignancy who had either failed to achieve complete remission with initial cisplatin, vinblastine, and bleomycin chemotherapy or who had relapsed after complete response (CR) to this therapy and then proven refractory on retreatment, were treated with etoposide (75 mg/m2 for 3 days), dactinomycin (1 mg/m2 day 1), and methotrexate (30 mg/m2 day 1) (EAM) every 3 weeks. Courses were continued until maximum response without empirical limit, and if complete remission was achieved, two courses of consolidation therapy were given before cessation of treatment. Thirteen patients (25%) were complete responders with residual masses containing fibrosis or benign teratoma being subsequently resected in seven patients. Two patients had persisting viable carcinoma within residual masses that were completely resected, leaving no evidence of disease (NED); the combined CR plus NED rate was 29%. The only pretreatment factor significantly influencing this response rate was tumor volume. Toxicities were moderate, with leukopenia being observed in 28% of patients, but it was severe in only 2%. There was one death from septicemia. Severe nausea and vomiting occurred in only 9% of patients and treatment-related stomatitis was observed in 42%. All patients achieving CR plus NED have been followed for a minimum of 5 years and no relapses have occurred, suggesting that these patients are cured. Unlike other regimens of salvage chemotherapy, this treatment program did not contain cisplatin and it is contended that a completely noncrossresistant drug regimen based on etoposide provides the opportunity to further improve the curability of patients with advanced germ cell cancer. 相似文献
996.
Health access America--strengthening the US health care system 总被引:1,自引:0,他引:1
Although Americans remain generally satisfied with the health care provided to them, sufficient access to high-quality, affordable health care for citizens without health care insurance has become an increasing problem in the last decade. Using the policy development process of the American Medical Association, Health Access America was conceived by the Association to improve access to affordable, high-quality health care. The proposal consists of six fundamental principles and 16 key points. This article specifically focuses on the five points that, if enacted into law, would improve access to health care for Americans who are, for various reasons, without health insurance. 相似文献
997.
N S Harvey 《Psychosomatics》1986,27(3):175-7, 180, 181-4
998.
Comparative Anticonvulsant Activity and Neurotoxicity of Felbamate and Four Prototype Antiepileptic Drugs in Mice and Rats 总被引:31,自引:30,他引:1
Felbamate (2-phenyl-1,3-propanediol dicarbamate), phenytoin, phenobarbital, ethosuximide, and valproate were evaluated in mice and rats with a battery of well-standardized anticonvulsant test procedures. The results obtained indicate that felbamate exhibits a wider range of experimental anticonvulsant activity than either phenytoin or ethosuximide and a somewhat more restricted range than either phenobarbital or valproate. Felbamate is effective in nontoxic intraperitoneal doses in mice by the maximal electroshock seizure (MES), pentylenetetrazol (s.c. PTZ), and picrotoxin (s.c. Pic) tests but ineffective against bicuculline- and strychnine-induced seizures; it is effective after nontoxic oral doses in both mice and rats by the MES and s.c. PTZ tests. When compared on the basis of protective indices (PI = TD50/ED50) calculated from the intraperitoneal data in mice, the PIs for felbamate were from 1.05 to 2.37 times higher than those of the prototype antiepileptics. Overall, except for the s.c. PTZ test in mice and rats after oral administration, the PIs were equal to or higher than those of the prototype agents. The PIs for the s.c. PTZ test in mice and rats after oral administration were within the range of the prototype agents. These data indicate that felbamate is a relatively nontoxic agent with a unique profile of anticonvulsant action. 相似文献
999.
1000.