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991.
Abstract: Two episodes of acute renal failure were present in an elderly patient following repeated exposure to radio-contrast agents. These episodes were due to acute interstitial nephritis with eosinophiluria but no systemic allergic reaction. 相似文献
992.
Thrombosis following desmopressin for uremic bleeding 总被引:2,自引:0,他引:2
An elderly patient with evidence of atherosclerosis and uremic bleeding diathesis developed two foci of cerebral thrombosis immediately after an infusion of desmopressin (DDAVP). Because large molecular weight multimers of von Willebrand factor (vWF) have been demonstrated to cause platelet aggregation under conditions of elevated fluid shear stress as occurs in atherosclerotic vessels, we investigated his plasma vWF at the time of the event and compared it to baseline values obtained 2 weeks later. Unusually large vWF multimers induced by the DDAVP infusion were present and likely contributed to the thrombotic process. Consequently, we believe DDAVP should be given with greater caution to patients with atherosclerosis. 相似文献
993.
Cells that generate splenic colonies within 8 days (day-8 colony- forming units-spleen [CFU-s]) are generally thought to differentiate only into erythroid/myeloid cells. The T and B lymphocyte differentiation potentials of day-8 CFU-s were evaluated and compared with those of day-12 and 5-fluorouracil (5-FU) CFU-s. This was achieved by analyzing, after intravenous and intrathymic injection, the lymphocyte progeny of cells contained within individual splenic colonies collected at day 8 and day 12 post-bone marrow cell transfer into irradiated congenic recipients. A large majority of day-8 spleen colonies generated T cells when transferred intrathymically. After intravenous (IV) injection of day-8 colonies, donor-type thymocytes emerged in 33% of the animals reconstituted with only 1 day-8 colony, but in 83% of those inoculated with a pool of 5 colonies. All post-5-FU and 75% of day-12 colonies gave rise to thymocytes after IV injection. B cells were generated by a high proportion of day-8 colonies, and by all day-12 and post 5-FU colonies. These results demonstrate that progenitors of T and B lymphocytes are generated within spleen colonies produced by at least some day-8 CFU-s and virtually all day-12 CFU-s. Whether these progenitors are CFU-s themselves or committed precursors remains an open question. 相似文献
994.
Sanz GF; Sanz MA; Vallespi T; Canizo MC; Torrabadella M; Garcia S; Irriguible D; San Miguel JF 《Blood》1989,74(1):395-408
Therapy planning in patients with myelodysplastic syndromes (MDSs) is complicated by its high prognostic heterogeneity. Forty-one patient and disease characteristics at onset of 370 patients with MDS were analyzed to identify significant prognostic factors for survival and transformation to acute myeloblastic leukemia (AML), and to develop and validate a regression model for predicting survival. Multivariate regression analysis showed that the total bone marrow percentage of blast cells, age, platelet count, WBC count, and hemoglobin level were the characteristics more significantly associated with survival in the overall series. The bone marrow percentage of type I blast cells was the most important factor predicting transformation into AML. Proportional hazards regression analysis in a randomly selected training sample of 240 patients demonstrated that the combination of total bone marrow percentage of blast cells, platelet count, and age had the strongest predictive relation to survival length. The resulting regression models, continuous and categorized, were validated in the remaining test sample of 130 patients by demonstrating its capability of segregating patients into low-, intermediate-, and high-risk groups, with distinctively different survival curves (P less than .0001). A scoring system derived from the categorized model also had a great prognostic value (P less than .0001). These regression models and the simpler scoring system may be accurately used for decision-making regarding therapy in MDS patients. 相似文献
995.
Additional glycoprotein defects in Bernard-Soulier's syndrome: confirmation of genetic basis by parental analysis 总被引:11,自引:2,他引:11
The glycoprotein profile of Bernard-Soulier platelets was examined by labeling washed platelets with periodate 3H-sodium borohydride, a procedure that labels greater than 30 glycoproteins on the membrane surface of normal platelets. Three Bernard-Soulier patients were studied; two were siblings and the third was unrelated. The platelet protein and glycoprotein profiles were evaluated under nonreduced and reduced conditions using 5%-15% exponential SDS-polyacrylamide gel electrophoresis. The two siblings completely lacked glycoprotein Ib (GPIb). The unrelated patient had congruent to 7% of the normal level. This was confirmed by two-dimensional nonreduced-reduced SDS- polyacrylamide gel electrophoresis, a procedure that allows clear separation of the disulfide-linked subunits of GPIb, GPIb alpha (mol wt 145,000), and GPIb beta (mol wt 25,000) from other membrane glycoproteins. On one-dimensional analysis, Bernard-Soulier's syndrome (BSS) platelets also lacked the peripheral membrane glycoprotein, GPV (mol wt 82,000) and a low molecular weight glycoprotein, GPIX, (nonreduced or reduced, mol wt congruent to 22,000). The two- dimensional gel system also revealed the absence of a minor glycoprotein with a molecular weight of congruent to 100,000 (GP 100). Quantitation of these proteins solubilized from electrophoretograms showed that the siblings' parents had congruent to 50% levels of GPIb, GPIX, and GP 100. A monoclonal antibody against glycoprotein Ib, FMC 25, was negative by immunofluorescence against Bernard-Soulier platelets and immuneprecipitated both GP Ib and GPIX from Triton X100 solubilized, labeled platelets. The combined results suggest that the apparent genetic absence of multiple proteins in Bernard-Soulier platelets is due, in part, to the presence in normal platelets of a tight membrane complex between glycoprotein Ib and at least one of the other absent glycoproteins. 相似文献
996.
An inherited hypochromic microcytic anemia transmitted in an autosomal manner has been observed in three generations of an English family. Affected members had the hallmarks of heterozygous beta-thalassemia, ie, elevated levels of hemoglobin A2 and imbalanced globin chain synthesis. However, despite extensive sequence analysis, no mutations could be found in or around the beta-globin genes of either the propositus or two other affected members from two different generations. Linkage analysis using restriction fragment length polymorphisms in the beta-globin gene cluster clearly showed that the gene responsible for the beta-thalassemia phenotype segregates independently of the beta-gene complex. Therefore, this condition represents a novel form of the disease. 相似文献
997.
G Dubos R Gonthier I Simeone V Camus P Schwed B Cadec MC Diana B Burtin M Melac 《La Revue de médecine interne / fondée ... par la Société nationale francaise de médecine interne》1996,17(12):979-986
Using explicit criteria contained in the DSM III R, we collected in a prospective cohort study clinical features, outcome and risk factors from two cohorts of delirium in hospitalized elderly patients: 138 hospitalized in geriatric department and 45 patients admitted to an acute and comprehensive care hospital. The clinical features were assessed using a quantitative scale (developed by Derouesné). Delirium was unrecognized or misdiagnosed by physicians in 34% of the cases. The onset was known only two thirds of cases. The incidence of hyperactive type, prolonged hospital stay, poor outcomes (persistent delirium leading up to dementia) were highest in subjects admitted in comprehensive hospital. The etiology of delirium is complex and multifactorial. An underlying cause was identified in 80% of patients. The length or the worsening of delirium was significantly higher in patients with psychiatric or dementia comorbidity (OR: 0.2; IC 95%: 0.1–0.5). The prognosis was better in patients without psychoactive medications (OR: 0.2; IC 95%: 0.1–0.4) or with metabolic abnormalities or acute diseases and disorders (OR: 3.3; IC 95%: 1.5–7.6). The predisposing factors to the development of dementia were prior use of psychoactive medications and signs of prior cognitive impairment. This article suggests delirium in elderly patients is associated with several outcomes. The prognosis should be improved at admission by specific scale and an evaluation of predisposing and precipitating factors. 相似文献
998.
EV Loftus Jr BA Olivares-Pakzad KP Batts MC Adkins DH Stephens MG Sarr EP DiMagno 《Gastroenterology》1996,110(6):1909-1918
BACKGROUND & AIMS: Intraductal papillary-mucinous tumor (IPMT) of the pancreatic ducts is increasingly recognized. This study investigated if clinical, imaging, or, histological features predicated outcome, formulated a treatment algorithm, and clarified relationships among IPMT, mucinous cystic neoplasms of the pancreas (MCN), and chronic pancreatitis. METHODS: The medical records, radiographs, and pathological specimens of 15 patients with IPMT (dilated main pancreatic duct or branch ducts with mucin overproduction) who were evaluated between October 1983 and January 1994 were reviewed. RESULTS: One patient had hepatic metastases. Fourteen underwent an operation (6 distal pancreatectomy, 4 total pancreatectomy, and 4 pancreaticoduodenectomy); all had dysplastic intraductal epithelium and chronic pancreatitis, whereas 3 had invasive adenocarcinoma. After a median of 25 months, 10 patients were alive; 3 of 4 with malignant and 2 of 11 with benign IPMT died (P < 0.05). Patients with or without carcinoma had similar clinical and radiographic features. A clinical diagnosis of chronic pancreatitis had been made in 9 patients with benign IMPT and in none with malignant IPMT (P < 0.05). CONCLUSIONS: IPMT is a dysplastic and likely precancerous lesion that is frequently diagnosed as chronic pancreatitis and is separate from MCN. Because it is not possible to distinguish noninvasive from invasive IPMT preoperatively, complete surgical excision of the dysplastic process is our treatment of choice whenever appropriate. (Gastroenterology 1996 Jun;110(6):1909-18) 相似文献
999.
Anterior sacral meningocele and the scimitar sign 总被引:1,自引:1,他引:1
Paul J. Kovalcik M.D. Dr. James B. Burke M.D. LCDR MC USNR 《Diseases of the colon and rectum》1988,31(10):806-807
Anterior sacral meningocele is an unusual lesion that usually presents as a presacral mass. This is a case presentation of a young woman who presented with amenorrhea. On physical examination, a large presacral mass was found. Ultrasonography revealed a large cystic structure. Radiography of the pelvis demonstrated a sacral deformity or "scimitar sign" that is pathognomonic for anterior sacral meningocele. The diagnosis was confirmed by computed tomography with myelographic enhancement. 相似文献
1000.
Steady state levels of factor X mRNA in liver and Hep G2 cells 总被引:1,自引:0,他引:1
Bahnak BR; Howk R; Morrissey JH; Ricca GA; Edgington TS; Jaye MC; Drohan WW; Fair DS 《Blood》1987,69(1):224-230