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81.
JI Elizalde ; J Clemente ; JL Marin ; J Panes ; B Aragon ; A Mas ; JM Pique ; J Teres 《Transfusion》1997,37(6):573-576
BACKGROUND: Equilibration of hemoglobin concentration after transfusion has been estimated to take about 24 hours, but some studies have shown that earlier measurements reflect steady-state values in persons who have not bled recently. This study was aimed at assessing the changes over time in hemoglobin concentration after transfusion in acutely anemic patients because of recent bleeding. STUDY DESIGN AND METHODS: Thirty-two normovolemic patients recovering from an acute bleeding episode who were no longer thought to be bleeding and who received a 2- unit red cell transfusion were studied. At baseline and 15, 30, 60, and 120 minutes and 24 hours after transfusion, hemoglobin concentration and hematocrit values were measured. RESULTS: The administration of 2 units of packed red cells elicited a 24-hour increase of 22.4 +/− 6.8 g per L in hemoglobin concentration. Hemoglobin values were not different at any of the defined posttransfusion times. Hematocrit levels experienced similar changes over time. Agreement between 15-minute and 24-hour values was excellent, as only 6 percent of patients exhibited a clinically significant difference (> 6 g/L) between the hemoglobin measurements. CONCLUSION: Hemoglobin and hematocrit values rapidly equilibrate after transfusion in normovolemic patients who are recovering from an acute bleeding episode. This fact would allow a rapid assessment of the effects of transfusion and of the recurrence of bleeding in patients remaining at risk. 相似文献
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James J. Kuhlman Barry Levine Rolley E. Johnson Paul J. Fudala Edward J. Cone 《Addiction (Abingdon, England)》1998,93(4):549-559
Aims. Examine the relationship between buprenorphine and norbuprenorphine plasma concentrations with subject-reported withdrawalsymptomatology during buprenorphine dose induction, maintenance treatment (daily and alternate-day dosing) and withdrawal . Design. Two groups of randomly assigned subjects inducted onto buprenorphine and maintained on 8 mg daily by the sublingual route for 18 days. Group 1 continued to receive daily buprenorphine to day 36. Group 2 subjects received alternate-day dosing of buprenorphine and placebo on days 19 to 36. Both groups received placebo on days 37 to 52 . Setting. Inpatient facilities at the Addiction Research Center, Intramural Research Center, NIDA, Baltimore, MD . Participants. Eleven male, heroin-dependent volunteers participating in a research study . Intervention. Medications for treatment of withdrawal symptoms were prescribed as needed after day 39 (72 hours after the last dose of buprenorphine) . Measurements. Plasma concentrations of buprenorphine and norbuprenorphine, withdrawal symptomatology and pupil diameter . Findings. The mean steady-state buprenorphine plasma concentration (24 hours) after daily administration of sublingual buprenorphine for study days 21-35 was 0.80 ng/ml, and the mean alternate day steady-state buprenorphine plasma concentration (24 hours) was 0.77 ng/ml. Daily and alternate day steady-state norbuprenorphine plasma concentrations were 1.10 and 0.90 ng/ml, respectively. Predicted alternate day steady-state buprenorphine and norbuprenorphine plasma concentrations at 48 hours were 0.49 ng/ml and 0.57 ng/ml, respectively. Withdrawal scores varied inversely with plasma concentration. There were no significant differences between Groups 1 and 2 during steady-state (days 21-35) with regard to withdrawal scale scores or pupillary diameter. The overall, mean terminal elimination half-lives for buprenorphine and norbuprenorphine were 42 and 57 hours, respectively . Conclusions. During daily buprenorphine maintenance, plasma concentrations greater than 0.7 ng/ml of buprenorphine and norbuprenorphine were associated with minimal withdrawal symptoms. The long elimination half-life of buprenorphine suggested that increasing the buprenorphine dose with alternate-day administration may provide an effective, flexible therapy regimen for the treatment of opioid dependence. 相似文献
85.
S R Levine I M Diaczok M J Deegan S N Kieran H Feit S B Elias K M Welch 《Archives of neurology》1987,44(6):678-679
A 44-year-old woman developed recurrent thrombotic cerebral cortical infarctions. IgG and IgM anticardiolipin antibodies were found, as was a thymoma. To our knowledge, these antiphospholipid antibodies, which may inhibit prostacyclin formation and alter platelet function, have not been previously associated with this thymic neoplasm, an association we believe is not coincidental. 相似文献
86.
Sinonasal undifferentiated carcinoma. An aggressive neoplasm derived from schneiderian epithelium and distinct from olfactory neuroblastoma 总被引:2,自引:0,他引:2
H F Frierson S E Mills R E Fechner J B Taxy P A Levine 《The American journal of surgical pathology》1986,10(11):771-779
Eight cases of a highly aggressive undifferentiated carcinoma of the nasal cavity and paranasal sinuses are described. The patients, who ranged in age from 30-77 years, had multiple sinonasal symptoms, and each had involvement of the nasal cavity, maxillary antrum, and ethmoid sinus. Six tumors extended into the orbital bones, and five penetrated the cranial cavity. Five patients died of disease from 1 to 41 months after diagnosis (median: 4 months), and three are alive with tumor less than 1 year following diagnosis. Microscopically, the neoplasms formed nests, trabeculae, and sheets containing medium-sized cells with small to moderate amounts of eosinophilic cytoplasm. A high mitotic rate, tumor necrosis, and prominent vascular permeation were characteristic. Seven neoplasms were immunoreactive for cytokeratin, five for epithelial membrane antigen, and four for neuron-specific enolase. Ultrastructurally, occasional small desmosomes and rare membrane-bound, dense-core granules were observed. Sinonasal undifferentiated carcinoma is a distinctive clinicopathologic entity that must be distinguished from other, less aggressive sinonasal neoplasms. 相似文献
87.
Andres A; Morales JM; Praga M; Campo C; Lahera V; Garcia-Robles R; Rodicio JL; Ruilope LM 《Nephrology, dialysis, transplantation》1997,12(7):1437-1440
BACKGROUND: Cyclosporin has been shown to facilitate renal vasoconstriction
and to have an antinatriuretic effect. The existence of an interference of
cyclosporin with the vasodilating properties of endothelium mediated by
nitric oxide production could mediate these effects. On the other hand, the
infusion of the nitric oxide precursor L-arginine has been shown to induce
renal vasodilatation and to facilitate natriuresis in normal volunteers. We
have investigated the renal effects of the administration of an infusion of
L-arginine in renal transplant patients chronically treated with
cyclosporin. To facilitate the analysis of the data the effects of the
administration of a similar dose of cyclosporin on renal function during
the infusion of a vehicle were also investigated during the administration
of a vehicle of L-arginine. DESIGN: Ten male renal transplant patients,
chronically treated with cyclosporin and with a stable renal function were
studied during 2 consecutive days after the administration of the usual
morning dose of cyclosporin. The first day they received an intravenous
infusion of vehicle and the second the infusion of graded doses of
L-arginine (50, 100, 150 mg/kg/h) during 3 consecutive h. RESULTS: The
first day, after cyclosporin administration a significant fall (P <
0.01) was observed in natriuresis and kaliuresis in the absence of changes
in renal plasma flow and glomerular filtration rate. After the
administration of L-arginine significant (P < 0.01) increases of renal
plasma flow, glomerular filtration rate, and natriuresis were seen. The
increase in blood levels of cyclosporin after its administration did not
differ between days 1 and 2. CONCLUSION: These results indicate that
L-arginine facilitates renal vasodilatation and natriuresis in renal
transplant patients. Furthermore, the observed increase in sodium excretion
could indicate that L-arginine counteracts the antinatriuretic effect of
cyclosporin.
相似文献
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P. R. Schauer W. H. Schwesinger C. P. Page R. M. Stewart B. A. Levine K. R. Sirinek 《Surgical endoscopy》1997,11(1):8-11
Background: This study examines the notion that gastrointestinal endoscopy performed by supervised surgical residents is safe.
Methods: We reviewed all gastrointestinal endoscopic procedures performed by surgical residents with faculty supervision for complications
and deaths occurring up to 30 days following the procedures.
Results: The overall complication rate for 9,201 upper and lower endoscopy procedures was 1.4% and 0.42%, respectively. Overall mortality
rate was 0.76% for upper endoscopy and 0.6% for lower endoscopy. No mortality was a direct result of a procedure-related complication.
Intestinal perforation, drug overdose, bleeding, and aspiration were the most common procedure-related complications. Each
resident completed an average of 75 upper endoscopies and 79 lower endoscopies during their training period.
Conclusions: Gastrointestinal endoscopy can be performed safely by surgical residents with appropriate supervision. The higher morbidity
and mortality of upper endoscopy are most likely related to the underlying disease rather than the procedure. Awareness of
common complications and application of appropriate precautions and instruction are critical for minimizing complications.
Received 25 March 1996/Accepted: 24 April 1996 相似文献