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131.
C W Pinson M R Daya K G Benner R L Norton K E Deveney N L Ascher J P Roberts J R Lake A G Kurkchubasche J W Ragsdale 《American journal of surgery》1990,159(5):493-499
Amanita phalloides mushroom poisoning is an increasingly common and potentially lethal problem for which liver transplantation offers definitive therapy in selected patients. When significant liver dysfunction appears, early transfer to a liver transplant center is important to identify appropriate candidates and to begin the search for a donor organ. The clinical course of five severely poisoned patients, four of whom underwent liver transplantation, is reviewed. Indications for transplantation included primarily a markedly prolonged prothrombin time that was only partially correctable and a constellation of findings including metabolic acidosis, hypoglycemia, hypofibrinogenemia, and increased serum ammonia, following a marked elevation in serum aminotransferase levels. Unlike viral fulminant hepatic failure, grade III or IV hepatic encephalopathy, marked elevation of the serum bilirubin level, and azotemia were not indications for transplantation. Resected livers demonstrated hepatocyte viability of 0% to 30%. Manifestations of Amanita poisoning complicating preoperative and/or postoperative care included severe diarrhea, gastrointestinal hemorrhage, hypophosphatemia, bowel edema, and marrow suppression with lymphopenia, thrombocytopenia, and neutropenia. All five patients are well 1 year later. This largest experience with liver transplantation for Amanita poisoning further defines the early clinical and laboratory indications for, and the unique complicating features of, transplantation in this setting. 相似文献
132.
Ectopic Pregnancy in Lower Segment Uterine Scar 总被引:19,自引:0,他引:19
H. Roberts FRACOG COGUS C. Kohlenber FRACOG DDU V. Lanzarone MRACOG H. Murray FRACOG 《The Australian & New Zealand journal of obstetrics & gynaecology》1998,38(1):114-116
Summary: A case of ectopic pregnancy in a lower uterine segment scar following previous Caesarean section is reported. A significant scar defect may result in deep implantation within the myometrium with the risk of persistent pain and bleeding followed inevitably by uterine rupture. In this report we discuss a number of management options. Except in the special situation of superficial implantation in a shallow scar defect where there is ultrasound evidence of continuity of the gestational sac with the uterine cavity we would strongly advise termination of the pregnancy. 相似文献
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OBJECTS: to report the incidence of child pedestrian injury in New Zealand and review prevention strategies. METHODS: examination of National Health Statistics Centre mortality and public hospital morbidity data from 1978-87. RESULTS: over the ten year period, there was an annual average of 30 deaths (3.6/100,000 per year) and 411 hospitalisations (49.4/100,000 per year) for child pedestrian injury. There has been no significant reduction in the fatality or hospital morbidity rate over this time. Pedestrian fatality rates are highest for boys and for children in the youngest age groups. Hospitalisation rates are over 2.5 times higher for Maori children than for nonMaori children. CONCLUSIONS: child pedestrian injury is an important public health problem in New Zealand for which there are few established prevention strategies. Controlled studies aimed at the identification of modifiable environmental factors are required. 相似文献
135.
Ribavirin disposition in high-risk patients for acquired immunodeficiency syndrome 总被引:13,自引:0,他引:13
O L Laskin J A Longstreth C C Hart D Scavuzzo C M Kalman J D Connor R B Roberts 《Clinical pharmacology and therapeutics》1987,41(5):546-555
Ribavirin is a broad-spectrum antiviral drug that has in vitro activity against human immunodeficiency virus. To determine the kinetics of ribavirin, 17 symptom-free homosexual men with lymphadenopathy were studied. Single doses of ribavirin, 600, 1200, or 2400 mg, were given orally or intravenously. The plasma ribavirin concentration-time profiles were well fitted by a three-compartment open model. Ribavirin followed linear kinetics over the dose range studied. The mean 1-hour postinfusion concentrations after intravenous ribavirin, 600, 1200, and 2400 mg, were 8.0, 19.7, and 37.1 mumol/L, respectively. The mean +/- SD plasma beta-phase half-life, terminal-phase (gamma) half-life, and volume of distribution at steady state were 2.0 +/- 1.1 hours, 35.5 +/- 14.0 hours, and 647 +/- 258 L, respectively. The mean ribavirin renal clearance and total body clearance were 99 +/- 30 and 283 +/- 37 ml/min, respectively. After an oral dose of 600, 1200, and 2400 mg, the mean peak plasma ribavirin concentrations (which occurred 1.5 hours after administration) were 5.1, 9.9, and 12.6 mumol/L, respectively. The mean absorption half-life and bioavailability of ribavirin were 0.5 hour and 45%. Ribavirin had no plasma protein binding and the drug accumulated within red blood cells. In conclusion, ribavirin is incompletely absorbed from the gastrointestinal tract, its renal excretion accounts for approximately one third of the drug's elimination, and drug accumulation (greater than threefold) will result with repetitive dosing at the 6- to 8-hour dosing interval currently used. 相似文献
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Adult rat urothelial cells were transformed in vitro following treatment with a single dose of N-methyl-N-nitrosourea (MNU) or MNU treatment followed by promotion with sodium saccharin. This in vitro transformation process involves multiple steps: slow-growing 'pre-neoplastic' epithelial foci are induced 70-100 days after MNU treatment and from such foci rapidly proliferating immortal cell lines were established, some of which became tumorigenic after a further latent period. A series of epithelial cell lines and a single fibroblast cell line established in this way were analysed for the presence of transforming genes by DNA transfection into NIH3T3 cells. None of the epithelial cell lines induced foci in a focus formation assay. The single non-epithelial line induced foci and was found to contain an activated c-Ki-ras gene with a G----A transition in codon 12. To assay for the possible presence of transforming genes which were not active in a focus formation assay, two of the epithelial lines were analysed further by co-transfection with a dominant selectable marker, followed by selection and inoculation into nude mice. No tumours were induced within the latent period for tumour production by control cells transfected with NIH3T3 cell DNA (40-60 days). These results suggest that there is cell type specificity for oncogene activation during in vitro rat bladder transformation initiated by a single carcinogen and that ras gene activation is not a necessary step in urothelial transformation in vitro. 相似文献
138.
Circulating antibodies to lung protein(s) in patients with cryptogenic fibrosing alveolitis. 总被引:4,自引:2,他引:2 下载免费PDF全文
W A Wallace S N Roberts H Caldwell E Thornton A P Greening D Lamb S E Howie 《Thorax》1994,49(3):218-224
BACKGROUND--It has been hypothesised that cryptogenic fibrosing alveolitis has an immunological pathogenesis mediated by T lymphocytes. It is, however, recognised that patients may show dysregulation of the humoral immune system and that the presence of large numbers of B lymphocytes in open lung biopsies may be associated with a poor prognosis. Evidence of a role for the humoral immune system in the pathogenesis of cryptogenic fibrosing alveolitis has been suggested, but attempts to demonstrate circulating immunoglobulin to antigen within the lung have been inconclusive. METHODS--Plasma samples from 22 patients with cryptogenic fibrosing alveolitis, 22 patients with sarcoidosis, and 17 healthy controls were screened by SDS-PAGE and Western blotting for the presence of autoantibodies to lung proteins derived from cryptogenic fibrosing alveolitis, sarcoid and control lung tissue, as well as four normal non-pulmonary tissues. Possible site(s) of target protein(s) within the lung tissue were identified by immunohistochemical examination using IgG purified from the plasma of six patients and two controls. RESULTS--Eighteen of the plasma samples from patients with cryptogenic fibrosing alveolitis had reactive IgG to lung protein(s) in the 70-90 kDa molecular weight range compared with five of 18 plasma samples from patients with sarcoidosis and one of 17 controls. Plasma from patients with cryptogenic fibrosing alveolitis recognised antigen(s) of the same molecular weight in control and sarcoid lung tissue, but not non-pulmonary tissues, with a similar frequency. Immunohistochemical staining of cryptogenic fibrosing alveolitis biopsy material using IgG purified from plasma samples from patients with cryptogenic fibrosing alveolitis, but not control samples, revealed fine linear positivity in the lung parenchyma in a pattern suggestive of reaction with alveolar lining cells. The pattern was cytoplasmic/membranous and not nuclear. CONCLUSIONS--Patients with cryptogenic fibrosing alveolitis have a high frequency of plasma IgG autoantibodies to protein(s) within lung tissue associated with alveolar lining cells. This is believed to be the site where immunological injury occurs in cryptogenic fibrosing alveolitis, but the significance of these antibodies to the aetiology and pathogenesis is as yet unclear. 相似文献
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